Giovanni Favuzzi

Haplotype M2 in the annexin A5 (ANXA5) gene and the occurrence of obstetric complications

Inherited or acquired thrombophilias have been largely explored as a cause of pregnancy complications. However, pathogenesis of obstetric complications, as fetal loss and pregnancy-related hypertensive disorders is still partly unexplained. Recently, a common haplotype (M2) within the annexin A5 (ANXA5) gene has been described as a risk factor in recurrent fetal losses (RFL). It has been demonstrated to reduce the promoter activity of the ANXA5 promoter in luciferase reporter assays. Aim of this study was to investigate the prevalence of M2 haplotype in three different settings of women with previous obstetric complications: RFL, intra-uterine fetal death (IUFD) and pregnancy-related hypertension (gestational hypertension [GH] and pre-eclampsia [PE]). One hundred three patients with previous RFL, 54 with IUFD, 158 with hypertensive disease (67 GH, 91 PE) were investigated. As controls, 195 women from the same ethnic background with uneventful pregnancies were enrolled. Logistic regression, correcting for age, gravidity and parity showed that the ANXA5 haplotype is significantly and independently associated with the occurrence of RFL (3.1; 95%CI: 1.1-9.5; p = 0.047) and pregnancy-related hypertensive disorders (2.1; 95%CI: 1.2-3.5; p = 0.008). The M2 haplotype might be a new and relevant risk factor for obstetric complications.

Protein Z g-42a variant and the risk of pregnancy-related venous thromboembolism in a cohort of Italian patients

0049-3848/

Clinical histories and molecular characterization of two afibrinogenemic patients: Insights into clinical management

– see front matter

Clinical utility of screening for CALR gene exon 9 mutations in patients with splanchnic venous thrombosis

positive patients of a total of 13 haemophilics at 90 months [9]. Coagulation factor substitution was managed by bolus or continuous infusion and was stopped at a median of 1 day post-transplantation. During follow-up, no bleeding complications were reported in our study. Recurrence of HCV infection is a frequent problem after liver transplantation for hepatitis C cirrhosis. Some patients develop acute hepatitis in the graft during the early postoperative period and most will suffer from chronic liver disease. In this sense, Mc Carthy reported that 100% of their patients (n = 4) had evidence of recurrent viremia [10]. In our experience, 44% of the HCV recipients relapsed. Conclusion

A novel congenital dysprothrombinemia leading to defective prothrombin maturation

Clinical utility of screening for CALR gene exon 9 mutations in patients with splanchnic venous thrombosis -

Influence of the Gly1057Asp variant of the insulin receptor substrate 2 (IRS2) on insulin resistance and relationship with epicardial fat thickness in the elderly

INTRODUCTION Prothrombin deficiency is a very rare disorder caused by mutations in the F2 gene that generate hypoprothrombinemia or dysprothrombinemia and is characterized by bleeding manifestations that can vary from clinically irrelevant to life-threatening. AIM Here we characterize a patient with a novel missense mutation in F2, c.1090T/A (p.Val322Glu), that causes severe dysprothrombinemia. METHODS Coagulation assays, prothrombin Western Blotting, FII activation by Ecarin, fibrinogen degradation products quantification and thrombin generation assay were carried out to assess prothrombin expression and function. PCR followed by direct sequencing was carried out to characterize the mutation. In silico analysis for missense variant and molecular modeling were applied to predict the mechanism that leads to dysprothrombinemia. RESULTS AND CONCLUSIONS The homozygous patient had a markedly prolonged prothrombin time, strongly reduced FII activity (0.82%) but normal antigen levels. In the thrombin generation assay the lag time and the peak height were unmeasurable, suggesting that the Val322Glu mutation results in the inability of the mutant prothrombin to be fully activated to thrombin. In fact, prothrombin activation by ecarin was defective, with a massive accumulation of the meizothrombin intermediate. Molecular modeling and dynamic simulation studies showed that the Val322Glu mutation interferes with protein flexibility at Arg271 and Arg320. This impairs the switch of the protein from zymogen to proteinase, thus preventing the formation of thrombin. Accumulated meizothrombin, however, maintains some fibrinogen-degrading activity, as shown by the formation of FDPs, and this probably explains the patients mild bleeding phenotype.

Towards the genetic basis of cerebral venous thrombosis - The BEAST Consortium: A study protocol

Insulin receptor substrate 2 (IRS2) plays a crucial role in the regulation of insulin signaling. Several polymorphisms of the gene encoding IRS2 have been identified. The variant causing Gly1057Asp substitution is relatively frequent in humans and its impact on insulin sensitivity seems to be dependent on age and body weight. The aim of our study was to evaluate the relationships between Gly1057Asp variant and insulin sensitivity assessed by HOMA, and adiposity evaluated by measurement of epicardial fat (EpiF) thickness in the elderly. We studied 87 subjects, 42 men and 45 women, mean age±SD: 74.23±7.24years. In the subjects carrying the Gly1057Asp variant of the IRS2 gene we found higher HOMA index values (3.40±1.14 vs. 2.21±1.25, p<0.001) and increased epicardial adipose tissue (11.77±1.65 vs. 10.43±1.93mm, p<0.001) compared to wild type subjects. Univariate linear regression analyses evidenced that HOMA index was correlated with BMI (beta=0.152, p<0.001), fasting plasma glucose (beta=0.018, p=0.002), LDL cholesterol (beta=0.008, p=0.024), total cholesterol (beta=0.007, p=0.039), weight (beta=0.054, p<0.001), presence of Gly1057Asp variant (beta=1.185, p<0.001) and EpiF thickness (beta=0.540, p<0.001). In multivariate analysis HOMA index was still associated with the presence of the Gly1057Asp variant of the IRS-2 gene (beta=0.568, p=0.002) and with EpiF thickness (beta=0.414, p<0.001). Furthermore, a statistically significant positive correlation between EpiF thickness and HOMA was found (r=0.773, p<0.001) and this was not different between wild type control subjects and carriers of Gly1057Asp variant of the IRS2 gene (p=0.718). Similar results were obtained in comparing subjects with normal fasting glucose levels. In conclusion, in our elderly subjects the presence of the allelic variant Gly1057Asp of IRS2 gene was associated to the degree of insulin resistance assessed by HOMA index and with EpiF thickness, independently from the extent of obesity, suggesting its contribution to global cardiometabolic risk.

Coinheritance of three novel FV gene mutations in a patient with a severe FV deficiency

Introduction Cerebral venous thrombosis (CVT) is a rare cerebrovascular condition accounting for <1% of all stroke cases and mainly affects young adults. Its genetic aetiology is not clearly elucidated. Methods and analysis To better understand the genetic basis of CVT, we have established an international biobank of CVT cases, Biorepository to Establish the Aetiology of Sinovenous Thrombosis (BEAST) which aims to recruit highly phenotyped cases initially of European descent and later from other populations. To date we have recruited 745 CVT cases from 12 research centres. As an initial step, the consortium plans to undertake a genome-wide association analysis of CVT using the Illumina Infinium HumanCoreExome BeadChip to assess the association and impact of common and low-frequency genetic variants on CVT risk by using a case–control study design. Replication will be performed to confirm putative findings. Furthermore, we aim to identify interactions of genetic variants with several environmental and comorbidity factors which will likely contribute to improve the understanding of the biological mechanisms underlying this complex disease. Ethics and dissemination BEAST meets all ethical standards set by local institutional review boards for each of the participating sites. The research outcomes will be published in international peer-reviewed open-access journals with high impact and visibility. The results will be presented at national and international meetings to highlight the contributions into improving the understanding of the mechanisms underlying this uncommon but important disease. This international DNA repository will become an important resource for investigators in the field of haematological and vascular disorders.

Venous thromboembolism in assisted reproductive technologies: comparison between unsuccessful versus successful cycles in an Italian cohort

V. BAFUNNO,* G. FAVUZZI , T. FIERRO, M. CHETTA,* E. MASTRODICASA,§ E. CHINNI, E. GRANDONE, M. MARGAGLIONE* and P. GRESELE *Medical Genetics, Department of Biomedical Sciences, University of Foggia, Foggia; Atherosclerosis and Thrombosis Unit, Research Department, Istituto di Ricovero e Cura a Carattere Scientifico, Casa Sollievo della Sofferenza, S. Giovanni Rotondo, Foggia; Department of Internal Medicine, Section of Internal and Cardiovascular Medicine, University of Perugia, Perugia; and §Pediatric Onco-Hematology, S. Maria della Misericordia Hospital, Perugia, Italy

Factor XI deficiency: two novel mutations in asymptomatic Italian patients

Pregnancies after assisted reproductive technologies (ART) have been associated with an increased risk of venous thromboembolism (VTE). On the contrary, the magnitude of this risk in unsuccessful ART cycles (not resulting in a clinical pregnancy) has not yet been clearly defined. In this study, we evaluated the incidence of VTE in unsuccessful cycles and compared it with that recorded in successful cycles in the same study population. From a cohort of 998 women consecutively referred by local Fertility Clinics to our Atherosclerosis and Thrombosis Unit (April 2002–July 2011), we identified and included women with at least one cycle of ovarian stimulation and a negative history for VTE. Overall, 661 women undergone 1518 unsuccessful and 318 successful cycles of ovarian stimulation, respectively, were analysed. VTE events occurred in 2/1518 (1.3‰) unsuccessful cycles compared with 3/318 (9.4‰) successful cycles, (Two-tailed Fisher exact test, p = 0.04, OR 0.14, 95% CI 0.02–1.02). Both cases observed in unsuccessful cycles were isolated pulmonary embolism occurred after OHSS; no antithrombotic prophylaxis had been prescribed. At logistic regression analysis, the occurrence of successful cycle and BMI were significantly and independently associated with the occurrence of VTE with an OR of 13.94 (95% CI 1.41–137.45) and 1.23 (95% CI 1.01–1.49), respectively. VTE incidence is significantly lower in unsuccessful cycles as compared to that of successful ones. However, although rare, thrombotic risk during ovarian stimulation cannot be excluded and, when it occurs, can be life-threatening. Therefore, particular attention should be paid to these women, independently of ART outcome.