Violetta Kapsimali

Etiopathogenesis of Behçet's disease with emphasison the role of immunological aberrations

Behçets disease (BD) is a chronic multisystemic inflammatory disorder of unknown origin consisting of oral aphthous ulcers, ocular symptoms, skin lesions, and genital ulcerations. It has many features in common with systemic vasculitides and is more prevalent in countries along the ancient Silk route. Immune-mediated mechanisms play a major role in the pathogenesis of the disease, and inflammatory mediators are also involved. BD is not considered to be an autoimmune disorder, and the character of the disease needs to be clarified. Immunological aberrations in BD have been extensively studied by many investigators; genetic factors have been related to disease susceptibility, but their exact role in the development of disease is uncertain. Environmental factors such as infectious agents have also been implicated in the etiology of BD. However, the etiopathogenesis of the disease remains to be elucidated. Factors involved in the immunopathogenesis of BD with emphasis on the role of immunological aberrations are analyzed in this review.

Plasminogen activator inhibitor-1 4G/5G polymorphism and risk of ischemic stroke : a meta-analysis

This study investigated the hypothesis that the insertion/deletion (4G/5G) polymorphism of the plasminogen activator inhibitor type-1 gene affects the risk for ischemic stroke, since results concerning this association have been controversial. We therefore performed a meta-analysis of published data regarding this issue. A comprehensive electronic search was carried out until January 2006. The analysis was performed using random-effects models and meta-regression. Eighteen eligible studies were retrieved (15 case–control studies and three cohort studies). The case–control studies included 3104 cases and 4870 control individuals concerning the contrast of 4G/4G versus remaining genotypes. The 4G pooled allele frequencies in cases and controls were 54.21 and 54.75%, respectively. Overall, the per-allele odds ratio of the 4G allele was 0.98 (95% confidence interval, 0.858–1.121). Regarding genotypes, we derived nonsignificant odds ratios in all contrasts. The subanalysis including the three studies with a prospective design in the 4G/4G versus 5G/5G contrast derived a significant result (relative risk, 0.523; 95% confidence interval, 0.353–0.775), but the estimated effect size was insignificant when cohort and case–control studies were analyzed together (relative risk, 0.848; 95% confidence interval, 0.662–1.087). We failed to demonstrate a significant association between the 4G/5G polymorphism and ischemic stroke under basal conditions. Determination of plasminogen activator inhibitor type-1 function seems of much higher clinical value than determination of the 4G/5G polymorphism. The effect of this genotype on risk of ischemic stroke in acute stressful diseases and the role of cohort studies in genetic epidemiology, however, warrant further investigation.

Evaluation of current therapeutic strategies in Behçet's disease.

Behçet’s disease (BD) is a chronic relapsing vasculitis with multifunctional pathogenesis. The mucocutaneous and ocular lesions are the commonest manifestations, but BD also affects the musculoskeletal, intestinal, cardiac, and central nervous system. BD therapy is based on the suppression of the inflammatory process, using immunomodulating and immunosuppressive agents. In selected cases, invasive procedures may be required.

Evaluation of the role of the new INNOVANCE PFA P2Y test cartridge in detection of clopidogrel resistance

Light transmittance aggregometry (LTA) has been extensively used in monitoring clopidogrel therapy. However, the availability of simple and rapid point-of-care platelet function assays is of great clinical importance. Thus, the manufacturer of the Platelet Function Analyzer (PFA)-100 System has recently produced the INNOVANCE PFA P2Y test cartridge. We assessed the ability of this new test to reliably detect clopidogrel resistance. We enrolled 90 consecutive patients with coronary artery disease receiving chronic clopidogrel maintenance therapy in combination with aspirin. Twenty healthy volunteers served as controls. Clopidogrel resistance was simultaneously analysed by the INNOVANCE PFA P2Y test cartridge, ADP-induced LTA, the flow-cytometric vasodilator-stimulated phosphoprotein (VASP)-phosphorylation assay and the multiple electrode aggregometry (Multiplate). Agreement among the four platelet function methods by two was assessed using Cohens kappa coefficient. According to the cut-off points for clopidogrel resistance proposed by the literature, agreement was fair between INNOVANCE PFA-100 P2Y and LTA (74.4%) and Multiplate (75.6%), while poor agreement was noticed in VASP assay (63.3%). Based on cut-off points indicating a higher thrombotic risk, agreement between the PFA-100 System and the other three methods did not significantly differ compared to the previous cut-offs (72.2%, 71.1% and 55.1%, respectively). The INNOVANCE PFA-100 P2Y test seems to be comparable to other established platelet function assays in detecting clopidogrel resistance. However, the modest agreement among platelet function methods makes the performance of platelet function testing crucial with more than one technique in order to reliably identify poor responders to clopidogrel treatment.

Cell cycle and apoptosis regulatory gene expression in the bone marrow of patients with de novo myelodysplastic syndromes (MDS)

Deregulation of cell cycle and apoptosis pathways are known contributors to the pathogenesis of myelodysplastic syndromes (MDS). However, the underlying mechanisms are not fully clarified. The aim of our study was to examine mRNA expression levels of cell cycle and apoptosis regulatory genes, as well as the percentage of apoptotic and S phase cells and to correlate the findings with clinical characteristics and prognosis. Sixty patients with MDS, classified according to FAB (17 RA, five RARS, 19 RAEB, nine RAEBT, ten CMML) and WHO (ten RA, three RARS, seven RCMD, two RCMD-RS, 11 RAEBI, eight RAEBII, ten CMML, and nine AML) were included in the study. We found increased expression of anti-apoptotic bclxL and mcl1 genes and decreased expression of p21 gene in MDS patients. Moreover, we found increased expression of anti-apoptotic mcl1 gene in patients with higher than Intermediate-1 IPSS group. Multivariate analysis confirmed that combined expression of apoptotic caspases 8, 3, 6, 5, 2, 7, and Granzyme B was decreased in MDS patients. Regarding cell cycle regulatory genes expression, we demonstrated increased expression of cyclin D1 in patients with CMML Increased combined expression of cyclins B, C, D1, and D2 was found in patients with cytogenetic abnormalities. The two pathways seem to be interconnected as shown by the positive correlation between CDKs 1, 2, 4, p21 and the level of apoptosis and positive correlation between apoptotic caspase 3 expression and the percentage of S phase cells. In conclusion, our study showed altered expression of genes involved in apoptosis and cell cycle in MDS and increased expression of cyclin D1 in patients with CMML.

The association between plasminogen activator inhibitor type 1 (PAI-1) levels, PAI-1 4G/5G polymorphism, and myocardial infarction: a Mendelian randomization meta-analysis

Abstract Background: The circulating levels of plasminogen activator inhibitor type 1 (PAI-1) are increased in individuals carrying the 4G allele at position –675 of the PAI-1 gene. In turn, overexpression of PAI-1 has been found to affect both atheroma and thrombosis. However, the association between PAI-1 levels and the incidence of myocardial infarction (MI) is complicated by the potentially confounding effects of well-known cardiovascular risk factors. The current study tried to investigate in parallel the association of PAI-1 activity with the PAI-1 4G/5G polymorphism, with MI, and some components of metabolic syndrome (MetS). Methods: Using meta-analytical Mendelian randomization approaches, genotype-disease and genotype-phenotype associations were modeled simultaneously. Results: According to an additive model of inheritance and the Mendelian randomization approach, the MI-related odd ratio for individuals carrying the 4G allele was 1.088 with 95% confidence interval (CI) 1.007, 1.175. Moreover, the 4G carriers had, on average, higher PAI-1 activity than 5G carriers by 1.136 units (95% CI 0.738, 1.533). The meta-regression analyses showed that the levels of triglycerides (p=0.005), cholesterol (p=0.037) and PAI-1 (p=0.021) in controls were associated with the MI risk conferred by the 4G carriers. Conclusions: The Mendelian randomization meta-analysis confirmed previous knowledge that the PAI-1 4G allele slightly increases the risk for MI. In addition, it supports the notion that PAI-1 activity and established cardiovascular determinants, such as cholesterol and triglyceride levels, could lie in the etiological pathway from PAI-1 4G allele to the occurrence of MI. Further research is warranted to elucidate these interactions.

Impact of the proton pump inhibitors and CYP2C19*2 polymorphism on platelet response to clopidogrel as assessed by four platelet function assays

BACKGROUND Previous studies suggested a possible negative interference of proton pump inhibitors (PPIs) on clopidogrels antiplatelet effect because of the competitive inhibition of the CYP 2C19 isoenzyme. Moreover, carriers of the loss-of-function allele of CYP2C19 polymorphism (CYP2C19*2) display significantly lower responses to clopidogrel. In this study, we investigated the association between CYP2C19*2 genotype, PPI intake and clopidogrel resistance in patients with coronary artery disease (CAD) and their effect on clinical outcome. METHODS We recruited 95 patients with CAD receiving chronic clopidogrel therapy in combination with aspirin. Platelet reactivity was simultaneously assessed by INNOVANCE PFA-100 P2Y, ADP-induced light transmission aggregometry (LTA), flow-cytometric vasodilator-stimulated phosphoprotein (VASP)-phosphorylation assay and multiple electrode aggregometry (Multiplate). Cardiovascular outcomes were recorded during 1-year follow-up period. RESULTS Only platelet reactivity assessed by measuring platelet phosphorylated-VASP demonstrated a significant higher platelet reactivity in carriers of CYP2C19*2 (p=0.023). The other methods displayed higher - but not statistically significant - platelet reactivity in patients carrying the CYP2C19*2 variant as compared with non-carriers. Patients on PPIs demonstrated almost similar suppression of platelet reactivity in comparison with those not treated with PPIs by all platelet function assays. In logistic regression analysis none of the platelet function assays measurements were related with clinical outcomes. Similarly neither CYP2C19*2 genetic variant nor PPI treatment were associated with adverse clinical events. CONCLUSIONS PPI co-administration did not influence clopidogrels antiplatelet effect on laboratory testing by all platelet function assays used. On the contrary, patients carrying CYP2C19*2 genotype had significantly higher residual platelet reactivity as estimated by VASP-phosphorylation assay.

Seroprevalence of hepatitis E in HIV infected patients in Greece.

HEV infection is an emerging public health problem worldwide Data concerning HEV infection in HIV+ patients in Greece is scare. The aim of the study was to determine HEV seroprevalence in patients with HIV infection in Greece. We studied 243 HIV(+) patients 214 men (88%) and 29 women (12%) with a median age of 45 years (range 19–83) who attended the HIV unit of Pathophysiology Department of Laikon General Hospital in Athens for the presence of anti‐HEV IgG antibodies with (EIA) (EIA HEV IgG, Adaltis, Rome, Italy Eighteen/243 patients (7.3%) were positive for HEV IgG antibodies, a seroprevalence that was not different from that described for the blood donors group from Greece There was no difference of the presence of HbsAg, hepatitis C and hepatitis A between the HEV(+) and HEV(−) patients. There was no statistically significant difference between the HEV(+) and HEV(−) group in terms of HIV acquisition, sexual orientation, median duration of HIV infection, ART treatment, or duration of ART. Only the median age of HEV(+) was 52years (35–78) while that of HEV(−) was 44years (19–83)(P = 0.03). Only 2/18(11.1%) HEV(+) HIV(+) patients had abnormal ALT and AST values. The seroprevalence of hepatitis E in HIV(+) patients in Greece seems to be the same with that of the general population thus implying that HIV infection is not a risk factor for HEV infection and only age shows a positive correlation with seropositivity. J. Med. Virol. 87:1517–1520, 2015.

Direct evidence for normalization of platelet function resulting from platelet count reduction in essential thrombocythemia.

Essential thrombocythemia is characterized by persistent elevation and functional disturbances of platelets. Both the platelet function analyzer-100 (PFA-100) collagen-epinephrine (CEPI) cartridge and aggregometry with epinephrine are considered sensitive and valid methods in detecting abnormal platelet function in essential thrombocythemia. We attempted to confirm that restoration of abnormal platelet function results from platelet count reduction in essential thrombocythemia, by using these two methods. Thirty-nine essential thrombocythemia patients were divided into two groups on the basis of their platelet count. Group A participants (n = 20) exhibited platelet counts greater than 500 × 109/l, whereas group B participants (n = 19) had platelet counts below this limit. Hematological parameters, plasma von Willebrand factor (vWF) antigen and activity levels were assessed. Platelet function was analyzed by the PFA-100 and light transmission aggregometry with epinephrine, collagen, and ADP. The point mutation JAK2 V617F was identified and its effect on platelet function tests was also investigated. By using logistic regression analysis, white blood cell count, vWF activity level, and the measurements of aggregation in response to epinephrine were significantly different between the two groups. Epinephrine-induced aggregation retained the statistical significance in the multivariable procedure (P : 0.002). PFA-100 CEPI closure times were lower – but not statistically significant – in group B. Neither the JAK2 V617F positivity nor different cytoreductive treatments had any influence on ex-vivo platelet function tests. Our findings demonstrate normalization of platelet function resulting from platelet count reduction in essential thrombocythemia and reinforce the concept of lowering platelet counts in these patients.

Angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism and circulating ACE levels are not associated with outcome in critically ill septic patients.

Abstract Background: In critically ill patients independent studies have shown contradictory findings regarding the prognostic significance of the D/D genotype of the I/D angiotensin converting enzyme (ACE) polymorphism. The study aim was to evaluate the effect of both ACE I/D polymorphism and ACE serum levels on the clinical outcomes of critically ill septic patients. Methods: This study recruited 186 Caucasian patients with sepsis, severe sepsis or septic shock. Epidemiological, clinical data, co-morbidities and severity scores were recorded. Measurements of serum ACE activity and genotyping for ACE I/D polymorphism were carried out. Primary outcomes were the 28- and the 90-day mortality; secondary outcomes included the number of days without renal or cardiovascular failure and ventilation-free days over the 28-day period following study enrolment. Results: Neither 28- nor 90-day mortality were associated with ACE I/D polymorphism (p=0.59 and 0.34, respectively) or circulating ACE levels (p=0.17 and 0.25, respectively). Similarly, ACE polymorphism and levels were not related to ventilation-free days (p=0.14 and 0.25, respectively), days without cardiovascular failure (p=0.14 and 0.81, respectively) and days without renal failure (p=0.64 and 0.27, respectively). Conclusions: Neither ACE I/D polymorphism nor serum ACE levels seem to be significant prognostic factors of clinical outcomes in septic, critically ill patients.