Mitochondrial dysfunction, persistent oxidative damage, and catalase inhibition in immune cells of naïve and treated Crohn's disease.

Background: Oxidative stress is considered a potential etiological factor for Crohn's disease (CD). We characterized the reactive oxygen species (ROS) generated in immune peripheral cells of CD patients, as well as their antioxidant enzyme status and the presence of oxidative damage. In addition, mitochondrial function (DeltaPsim) was analyzed to detect the possible origin of ROS.

Superoxide dismutase and catalase anti-oxidant activity in leucocyte lysates from hypertensive patients: effects of eprosartan treatment.

Introduction: In an earlier study, our group reported that circulating leucocytes in hypertensive (HT) patients show a significant increase in oxidative stress compared to the control group, and this normalised after two months of treatment with eprosartan.(1) It can be speculated that these facts may be attributable to a possible reduction in anti-oxidative activity in untreated HT patients, which would be corrected by eprosartan.

Materials And Methods: In this observational pilot study, superoxide dismutase and catalase activities were evaluated in leucocyte lysates in a group of 21 HT patients at baseline and after two months of treatment with eprosartan (600 mg/ day).

Erythrocyte membrane phosphatidylserine exposure in obesity.

It has been suggested that increased erythrocyte membrane phosphatidylserine (PS) exposure could contribute to hypercoagulability and hemorheological disturbances in obesity. The aim of our study was to evaluate PS exposure in obese patients and in a control group and to correlate this with hemorheological properties, i.e.

[Platelet activation and hypercholesterolemia in the pathogenesis of deep vein thrombosis].

Currently it is accepted that deep vein thrombosis is a multifactorial event in which the presence of activated platelets and also plasmatic lipids seems to play a pivotal role that it is not well established in the scientific bibliography. Due to the non consensus state about these topics between the different groups working in these aspects, the topic involving deep vein thrombosis-platelets-lipids, and also their interactions, still is an interesting area of investigation, in which it is necessary to carry out studies with the aim of establishing risk factors, initial diagnostic methods and clinical assays to probe the efficacy of new therapies.

Cytoplasmic free calcium mobilization in platelets, expression of P-selectin, phosphatidylserine, and microparticle formation, measured by whole blood flow cytometry, in hypertensive patients. Effect of doxazosin GITS.

The effects of doxazosin on expression of CD62 (P-selectin) and phosphatidylserine on platelet membrane and platelet calcium flux were studied in 50 uncomplicated essential hypertensive patients (World Health Organization stages 1-2) and 80 normotensive control subjects, matched for age, sex, and cardiovascular risk factors. Hypertensive patients showed greater in vivo platelet activation at baseline than control patients (percentage of CD62-positive platelets, 4.1+/-2.

Effect of doxazosin gastrointestinal therapeutic system on platelet degranulation and platelet-leukocyte microaggregate formation induced by physiologic shear stress in hypertension.

Introduction: In this prospective, ex vivo, single-blind study, the effect of doxazosin on platelet function was studied in patients with hypertension.

Materials And Methods: Platelet activation by shear stress was measured in whole blood samples of 22 hypertensive patients and 22 normotensive controls, using flow cytometry. Sheared samples were evaluated for CD62 expression, microaggregate formation, and Ca2+ mobilization.

Effect of atorvastatin upon platelet activation in hypercholesterolemia, evaluated by flow cytometry.

Hyperlipidemia is a well established risk factor for cardiovascular disease and atherothrombotic events, in which platelet activation also plays a significant role. However, very few studies have addressed platelet activation in hypercholesterolemia, the potential effect of lipid lowering drugs upon platelet hyperfunction, and the question of whether changes in the latter are correlated to normalization of plasma lipids. This study used whole blood flow cytometry to assess in vivo and in vitro platelet activation in a group of 33 patients with hypercholesterolemia, and also the ex vivo effect of atorvastatin (20 mg/day) upon such activation.

Effect of eprosartan on cytoplasmic free calcium mobilization, platelet activation, and microparticle formation in hypertension.

Background: Hypertensive patients show greater platelet activation than do normotensive individuals. Platelet activation is characterized by increased phosphatidylserine (PS) exposure in the external hemilayer of the membrane, a larger number of platelet microparticles (PMP), and changes in intraplatelet-free calcium kinetics. This study evaluated whether eprosartan can protect against undesirable platelet activation.

Incidence of post-thrombotic syndrome and its association with various risk factors in a cohort of Spanish patients after one year of follow-up following acute deep venous thrombosis.

Post-thrombotic syndrome (PTS) is a frequent complication of deep venous thrombosis (DVT). However, neither the incidence nor the moment of PTS appearance are known. The main reason are the criteria used to define PTS, the characteristics of the patients, the study design and the time of follow-up.

Flow cytometric analysis of platelet activation in hypertensive patients. Effect of doxazosin.

The percentage of spontaneously activated platelets and the platelet response to several agonists were studied in 26 hypertensive patients. The percentage of platelets expressing glycoprotein (GP) IIb/IIIa in its active conformation (GPIIb/IIIa*), P-selectin and phosphatidylserine (PS) was measured by flow cytometry at baseline and 1 and 2 months after treatment with doxazosin (4 mg/day). The response to ADP and Ca2+ ionophore was also evaluated.

Platelet-erythrocyte interactions enhance alpha(IIb)beta(3) integrin receptor activation and P-selectin expression during platelet recruitment: down-regulation by aspirin ex vivo.

Activated platelets release biologically active compounds, which then recruit additional platelets into an evolving thrombus. We studied activation of alpha(IIb)beta(3) and exposure of P-selectin on platelets recruited by releasates obtained from collagen-treated platelets and evaluated modifications in prothrombotic effects of releasates induced by platelet-erythrocyte interactions and aspirin treatment. Releasates from collagen-stimulated platelets induced alpha(IIb)beta(3) activation and P-selectin exposure (monitored by flow cytometry using fluorescein isothiocyanate-PAC-1 and phycoerythrin-CD62 antibodies).

Biological risk factors for deep vein trombosis.

Hypercoagulable states due either to inherited or acquired thrombotic risk factors are only present in approximately half of cases of DVT, but the causes in the other half, remain unknown. The importance of biological risk factors such as hyperlipidemia, hypofibrinolysis and hemorheological alterations in the pathogenesis of DVT has not been well established. In order to ascertain whether the above mentioned biological factors are associated with DVT and could constitute independent risk factors, we carried out a case-control study in 109 first DVT patients in whom inherited or acquired thrombophilic risk factors had been ruled out and 121 healthy controls age (42+/-15 years) and sex matched.