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G Di Minno

Publications and source records attributed to G Di Minno.

At least 37 records · Page 2Linked to original sources

The effect of the interleukin-6 c/g-174 polymorphism and circulating interleukin-6 on fibrinogen plasma levels.

BACKGROUND AND OBJECTIVES: C-reactive protein (C-RP) levels correlate with fibrinogen values and are predictive of coronary artery disease. Interleukin-6 (IL-6) strongly regulates the production of C-RP. A polymorphism (C/G-174) within the IL-6 gene has been shown to affect IL-6 gene expression and plasma concentrations. DESIGN AND METHODS: In 598 asymptomatic employees of a hospital in Southern Italy, we investigated the association between IL-6 C/G-174 gene variants and plasma fibrinogen levels. RESULTS: Subjects with IL-6 plasma levels >2.0 pg/mL had a higher body mass index (BMI) (24.5+/-1.2) than subjects with IL-6 levels below this cut-off value (23.7+/-1.2; p =0.005). No association was found with sex, cigarette smoking, or alcohol consumption (p always>0.05). When the whole sample was analyzed according to the IL-6 C/G-174 polymorphism, there was no difference with respect to age, sex, alcohol consumption, cigarette smoking, total cholesterol, triglycerides, and body mass index. Median plasma fibrinogen levels, as well as carriers of plasma levels of IL-6 >2.0 pg/mL and C-RP >0.33 mg/L, were similar among subjects with different IL-6 genotypes. Similarly, no difference was observed when only carriers of plasma levels of IL-6 >2.0 pg/mL were analyzed, whereas in those with C-RP >0.33 mg/L IL-6 GG carriers had significantly lower plasma fibrinogen levels. INTERPRETATION AND CONCLUSIONS: The investigation of the IL-6 C/G-174 polymorphism does not seem to be a useful tool for predicting raised plasma fibrinogen levels.

Adult↗

Familial thrombophilia and the occurrence of fetal growth restriction.

BACKGROUND AND OBJECTIVES: To evaluate the association between unexplained or gestational-hypertension-associated fetal growth restriction (FGR) and factor V Leiden, prothrombin A20210 mutations, and methylenetetrahydrofolate reductase (MTHFR) TT 677 genotype. DESIGN AND METHODS: Sixty-one women with a previous history of FGR and 93 parous women with uneventful pregnancies from the same ethnic background were investigated for the presence of factor V (FV) Leiden, prothrombin A20210 mutations, and MTHFR TT 677 genotype. Moreover, antiphospholipid antibodies, antithrombin, protein C, and total and free protein S antigen were determined in all patients. RESULTS: Among the controls, 2 (2.2%) carried the FV Leiden mutation, 19 (20.4%) were TT MTHFR homozygotes and 1 (1.6%) carried the prothrombin A20210 allele. The FV Leiden mutation was present in 8 women with FGR (13.1%, OR: 6.9, 95%CI 1.4-33.5), the TT MTHFR homozygosity in 17 (27.8%, OR: 1.5, 95%CI 0.7-3.2) and the A20210 prothrombin allele in 7 (11.5%, OR: 5.9, 95%CI 1.2-29.4). In six cases (9.8%) there was coexistence of more than one mutation (2 had the FV Leiden and the TT MTHFR genotype and 4 carried the A20210 prothrombin allele and TT MTHFR genotype). A logistic regression analysis showed that FV Leiden and A20210 prothrombin mutations were independently associated with the occurrence of FGR. INTERPRETATION AND CONCLUSIONS: Present data indicate an association between prothrombotic genetic factors and FGR.

Adolescent↗

Antithrombotic drugs for older subjects. Guidelines formulated jointly by the Italian Societies of Haemostasis and Thrombosis (SISET) and of Gerontology and Geriatrics (SIGG).

Older individuals contribute heavily to the percentage of deaths due to myocardial infarction (MI) and stroke. The incidence of venous thromboembolism (VTE) is highest in subjects > 65 years. Prospective intervention trials involving groups of clinically comparable subjects > or = 60 allow the following statements to be made with regard to the use of antithrombotic drugs in the elderly. Antiplatelet agents. To prevent recurrence of ischaemic stroke and MI in stable/unstable angina, MI, TIA/stroke or peripheral arterial disease, aspirin is the drug of choice. Clopidogrel is more effective than aspirin in this respect. Heparin. For the treatment of acute deep venous thrombosis (DVT) and pulmonary embolism (PE), intravenous standard heparin or subcutaneous standard heparin are effective (aPTT 1.5-2.0 times baseline values). As the risk of bleeding increases with age, low-molecular-weight heparins (LMWH) are preferable in the elderly. For the prophylaxis of VTE in general surgery in subjects at low-moderate risk, low-dose heparin or low doses of LMWH are effective. In subjects at high risk, adjusted-dose heparin plus physical devices or high-dose LMWH are recommended. The combination of heparin and aspirin is the standard treatment for unstable angina and non-Q wave MI. LMWH are as active as standard heparin in this indication. Vitamin K antagonists. For the chronic treatment of VTE, warfarin is also the treatment of choice (INR 2.0-3.0) in the elderly, though lower doses are needed due to their hypersensitivity to oral anticoagulants. For the prevention of thromboembolic stroke in patients > 75 with atrial fibrillation, warfarin is the drug of choice. Patients aged 65-75 may receive warfarin or aspirin. Thrombolytic agents. Thrombolytic agents are not recommended for treating DVT in the elderly because of their limited risk/benefit ratio and should be confined to massive PE. In the absence of contraindications, thrombolysis for MI may be considered in the elderly.

Aged↗

Inherited thrombophilic risk factors in a large cohort of individuals referred to Italian thrombophilia centers: distinct roles in different clinical settings.

BACKGROUND AND OBJECTIVES: Despite inherited thrombophilic risk factors being strongly associated with vein thrombosis, decisions on whether to screen subjects for these factors vary in different clinical settings. DESIGN AND METHODS: We calculated the prevalence of inherited thrombophilic risk factors in a large cohort of patients (n=1,238) with different clinical manifestations of vein thromboembolism. In the present cohort, screening for inherited thrombophilia was worthwhile among patients who developed vein thrombosis of the leg or cerebral vein thrombosis. Carriers of FV Leiden or FII A(20210) mutation more frequently had had deep vein thrombosis of the leg (OR: 4.35; 95% CI: 3.39-5.60), superficial vein thrombosis (OR: 3.34; 95% CI: 2.06-5.41), or cerebral vein thrombosis (OR: 2.77; 95% CI: 1.10-6.96). RESULTS: The screening program appeared to have a limited relevance in patients with isolated pulmonary embolism (OR: 2.13; 95% CI: 1.28-3.54), or mesenteric vein thrombosis (OR: 2.05; 95% CI: 1.22-3.44). INTERPRETATION AND CONCLUSIONS: The lack of association with inherited thrombophilia does not justify routine screening of patients with thrombosis of the upper extremities or with retinal vein thrombosis.

Adolescent↗

A frameshift mutation in the human fibrinogen Aalpha-chain gene (Aalpha(499)Ala frameshift stop) leading to dysfibrinogen San Giovanni Rotondo.

We have investigated a 53-yr-old asymptomatic white man with decreased functional, but not immunologic, fibrinogen plasma levels together with prolonged thrombin and reptilase times, detected through routine coagulation studies prior to a surgical procedure. A new heterozygous single nucleotide deletion (C) at position Ala499 within the Aalpha-chain gene was identified, which predicted changes of the corresponding amino acids encoded by the subsequent portion of the exon V and the appearance of a premature stop codon at position 518 (Aalpha[499]Ala frameshift stop). The new dysfunctional fibrinogen, San Giovanni Rotondo variant, was confirmed in vivo by SDS-PAGE analysis of HPLC-purified fibrinogen chains. Mass spectrum examination of the abnormal HPLC-purified peak gave an estimated mass (56,088 Da) similar to that predicted by DNA analysis of the mutated Aalpha-chain gene (56,088 Da) and, after tryptic digestion, the truncated Aalpha-chain was shown only in the propositus, who also carried normal Aalpha-chain. In addition, mass spectrum analysis of the tryptic digest of the abnormal chain confirmed the presence of a new and unpaired cysteine at the last position that was predicted to form a disulfide bridge with human serum albumin. Immuno-blot analysis confirmed that fibrinogen San Giovanni Rotondo variant, but not normal fibrinogen. contained substantial amounts of albumin. Present findings confirm that truncated Aalpha-chain lacking part of the terminal domain may be incorporated into mature fibrinogen molecules and normally secreted in the bloodstream.

Afibrinogenemia↗

A G-to-A mutation in IVS-3 of the human gamma fibrinogen gene causing afibrinogenemia due to abnormal RNA splicing.

Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by a hemorrhagic diathesis of variable severity. Although more than 100 families with this disorder have been described, genetic defects have been characterized in few cases. An investigation of a young propositus, offspring of a consanguineous marriage, with undetectable levels of functional and quantitative fibrinogen, was conducted. Sequence analysis of the fibrinogen genes showed a homozygous G-to-A mutation at the fifth nucleotide (nt 2395) of the third intervening sequence (IVS) of the gamma-chain gene. Her first-degree relatives, who had approximately half the normal fibrinogen values and showed concordance between functional and immunologic levels, were heterozygtes. The G-to-A change predicts the disappearance of a donor splice site. After transfection with a construct, containing either the wild-type or the mutated sequence, cells with the mutant construct showed an aberrant messenger RNA (mRNA), consistent with skipping of exon 3, but not the expected mRNA. Sequencing of the abnormal mRNA showed the complete absence of exon 3. Skipping of exon 3 predicts the deletion of amino acid sequence from residue 16 to residue 75 and shifting of reading frame at amino acid 76 with a premature stop codon within exon 4 at position 77. Thus, the truncated gamma-chain gene product would not interact with other chains to form the mature fibrinogen molecule. The current findings show that mutations within highly conserved IVS regions of fibrinogen genes could affect the efficiency of normal splicing, giving rise to congenital afibrinogenemia.

Afibrinogenemia↗

Homocysteine, coagulation, platelet function, and thrombosis.

Over the last 30 years, a growing body of evidence has documented the role of hyperhomocysteinemia (HHcy) as an independent vascular risk factor. However, the mechanisms through which elevated circulating levels of homocysteine (Hcy) cause vascular injury and promote thrombosis remain elusive. Most findings have been achieved in in vitro studies employing exceedingly high concentrations of Hcy, whereas only a few studies have been carried out in vivo in humans. In homocystinuric patients, homozygotes for mutations of the gene coding for the cystathionine beta-synthase enzyme, abnormalities of coagulation variables reflecting a hypercoagulable state, have been reported. In vitro studies provide a biochemical background for such a state. In homocystinuric patients, an in vivo platelet activation has also been reported. The latter abnormality is not corrected by the bolus infusion of concentrations of hirudin, which determines a long-lasting impairment of the conversion of fibrinogen to fibrin by thrombin; in contrast, it appears at least in part lowered by the administration of the antioxidant drug probucol. During the autooxidation of Hcy in plasma, reactive oxygen species are generated. The latter initiate lipid peroxidation in cell membranes (potentially responsible for endothelial dysfunction) and in circulating lipoproteins. Oxidized low-density lipoproteins (LDL) may trigger platelet activation as well as some of the hemostatic abnormalities reported in such patients. Thus the oxidative stress induced by Hcy may be a key process in the pathogenesis of thrombosis in HHcy. Accumulation of adenosylhomocysteine in cells (a consequence of high circulating levels of homocysteine) inhibits methyltransferase enzymes, in turn preventing repair of aged or damaged cells. This mechanism has been recently documented in patients with renal failure and HHcy and provides an additional direction to be followed to understand the tendency to thrombosis in moderate HHcy.

Adolescent↗

C-reactive protein in offspring is associated with the occurrence of myocardial infarction in first-degree relatives.

The relevance of elevated levels of C-reactive protein (CRP) in cardiovascular disease is gaining increasing recognition. A family history of coronary artery disease is a major determinant of coronary artery disease in the offspring. In a cohort of 1048 individuals without clinical evidence of atherosclerosis, we investigated the relationships between CRP levels and a family history of myocardial infarction. We measured CRP, fibrinogen, plasminogen activator inhibitor-1, total cholesterol, triglycerides, and some genetic polymorphisms: plasminogen activator inhibitor-1 (4G/5G), fibrinogen (Bbeta-chain G-->A(-455)), and angiotensin-converting enzyme insertion/deletion (I/D). Clinical data were collected by a World Health Organization-modified questionnaire for cardiovascular disease. When compared with subjects without first-degree relatives who had suffered a myocardial infarction (n=867), subjects with such first-degree relatives (n=181) were older (P=0.001), more often hypertensive (P<0. 001), and homozygous for the 4G allele (4G/4G) of the plasminogen activator inhibitor-1 gene (P=0.003). In addition, they had a higher body mass index (P=0.036), raised plasma fibrinogen (P<0.007) and total cholesterol (P<0.001) concentrations, and CRP levels >0.33 mg/L (P=0.005). In a multiple logistic regression analysis, age (odds ratio [OR] 1.03, 95% confidence interval [95% CI] 1.01 to 1. 05), total cholesterol (OR 1.35, 95% CI 1.11 to 1.65), plasminogen activator inhibitor-1 4G/4G (OR 1.72, 95% CI 1.20 to 2.45), and CRP levels >0.33 mg/L (OR 1.75, 95% CI 1.05 to 2.91) were all independently associated with a positive family history of myocardial infarction. We therefore conclude that raised levels of CRP independently identify the offspring of patients with a myocardial infarction.

Adult↗

Inherited thrombophilic risk factors and venous thromboembolism: distinct role in peripheral deep venous thrombosis and pulmonary embolism.

STUDY OBJECTIVES: To investigate whether the FII A(20210) mutation is associated with isolated pulmonary embolism (PE). DESIGN: Case-control study. SETTING: Five thrombosis centers in southern Italy. PATIENTS: Six hundred forty-seven consecutive referred patients with objectively documented venous thrombosis and 1,329 control subjects. MEASUREMENTS AND RESULTS: Medical histories were collected. The G-to-A transition at nucleotide 1691 within the factor V gene (FV Leiden) and the G-to-A transition at nucleotide position 20210 within the prothrombin gene locus (FII A(20210)), levels of anticoagulant factors, and levels of antiphospholipid antibodies were determined by standard techniques. Patients with deep venous thrombosis (DVT) of the lower extremities (n = 346) or with additional PEs (n = 175) showed similar prevalences of FV Leiden mutation (24.3% and 16.6%, respectively) and FII A(20210) mutation (14.2% and 12.6%, respectively), and similar deficiencies of natural anticoagulants (4.9% and 2.3%, respectively). In both groups, the frequencies of FV Leiden and/or FII A(20210) mutation were higher than those observed among 1,329 apparently healthy control subjects (4.8% and 4.4%, respectively; p < 0.0001). Among patients with isolated PE (n = 126), prevalences of FV Leiden (7.1%) and FII A(20210) mutation (8.7%) were similar to those of control subjects. Inherited thrombophilic abnormalities were less frequent among patients with PE only (15.6%) than among those with DVT only (37.0%; p < 0.001) or whose conditions were complicated by PE (28. 0%; p = 0.020). Adjusting for age and sex, FV Leiden mutation, FII A(20210) mutation, or both mutations were associated with DVT with PE (FV Leiden mutation: odds ratio [OR], 3.0; 95% confidence interval [CI], 1.6 to 5.5; FII A(20210) mutation: OR, 2.6; 95% CI, 1. 3 to 5.2; and both mutations: OR, 82.1; 95% CI, 7.5 to 901.2) or without PE (FV Leiden mutation: OR, 6.1; 95% CI, 4.0 to 9.3; FII A(20210) mutation: OR, 2.8; 95% CI, 1.7 to 4.8; and both mutations: OR, 167.5; 95% CI, 21.6 to 1,297.7), but not with isolated PE (FV Leiden mutation: OR, 1.2; 95% CI, 0.5 to 2.8; FII A(20210) mutation: OR, 1.2; 95% CI, 0.5 to 3.1; and both mutations: OR, 22.1; 95% CI, 1. 3 to 370.2). CONCLUSIONS: FII A(20210) mutation is associated with DVT in the lower extremities alone or when complicated by PE, but it is not associated with isolated PE.

Activated Protein C Resistance↗

Contribution of the cystathionine beta-synthase gene (844ins68) polymorphism to the risk of early-onset venous and arterial occlusive disease and of fasting hyperhomocysteinemia.

The frequency of the heterozygous 844ins68 mutation of the cystathionine beta-synthase (CBS) gene and of its association with the homozygous C677T transition of the methylenetetrahydrofolate reductase (MTHFR) gene, plasma fasting tHcy, folate and vitamin B12 levels were evaluated in 309 consecutive patients with objectively diagnosed early-onset venous (n = 200) or arterial thromboembolic disease (n = 109) recruited over 25 months in Milan (North Italy) and Naples (South Italy). The above gene polymorphisms were also evaluated in a population of 787 unmatched controls, 204 of whom--similar to patients for age- and sex-distribution--had fasting tHcy, vitamins and activated protein C resistance measured in their plasma. Moderate fasting hyperhomocysteinemia was detected in 15.5% of patients and in 5.9% of 204 controls (Mantel-Haenszel OR after stratification for type of occlusive disease and gender: 2.88; 1.48-5.32). The frequencies of the 677TT mutation of the MTHFR gene and of the heterozygous 844ins68 insertion of the CBS gene were not significantly different in the patient (19.4% and 6.9%) and the control population (16.5% and 7.8%), but the association of the two gene polymorphisms found in 3.9% of patients and in 1.1% of controls - was significantly associated with an increased risk of venous or arterial occlusive diseases (RR = 3.63; 1.48-8.91). The MTHFR 677TT mutation (RR: 6.92; 3.86-12.4) and its association with the 844ins68 insertion (RR: 21.9; 8.35-57.4), but not the isolated insertion (RR: 0.71), were more frequent in patients and controls with fasting hyperhomocysteinemia than in normohomocysteinemic subjects, irrespective of the type of occlusive disease (venous or arterial). When adjusted for determinants of hyperhomocysteinemia in the patient and the control populations (generalized linear model), fasting tHcy levels were significantly higher in subjects with association of the two gene abnormalities (24.2+/-3.8 micromol/L) than in subjects with the MTHFR 677TT mutation only (14.0+/-5.8 micromol/L, p = 0.004). Activated protein C resistance was significantly more prevalent in venous patients (9.9%) than in controls (3.9%, OR = 2.69; 1.08-6.88). Six of 21 venous patients with APC-resistance also had hyperhomocysteinemia (RR = 5.04; 0.68-37.6), but isolated fasting hyperhomocysteinemia retained statistical significance for the association with venous occlusive disease (RR = 2.84; 1.34-6.01). Heterozygosity for the 844ins68 mutation of the CBS gene is not per se a risk factor for premature arterial and/or venous occlusive diseases. However, when detected in combination with thermolabile MTHFR, it increases by almost 4-fold the risk of occlusive diseases (arterial and/or venous), by increasing the risk and the degree of fasting hyperhomocysteinemia.

Adult↗

Determination of atherogenesis in apolipoprotein E-knockout mice.

BACKGROUND AND AIM: Genetically-modified mice are the preferred model for studies on atherogenesis. Conventional procedures for determining lesion size and composition may be not very accurate, especially when only very small lesions are present. We provide here a detailed characterization of lesion components and the computer-assisted quantitative determination of atherogenesis in apolipoprotein E-knockout (apoE-/-) mice. METHODS AND RESULTS: Atherosclerotic lesions were detected at typical predilection sites in the aorta: the small curvature of the arch, the orifices of the brachiocephalic trunk, the left subclavia and common carotid artery, the branch sites of the mesenteric and renal arteries, the abdominal aorta, and the iliac bifurcation. We found that these lesions covered 20% of the aortic surface of apoE-/- on average compared with 1% of the wild type C57BL/6 mice (p < 0.00001). As expected, immunocytochemistry revealed "oxidation-specific" epitopes, i.e. epitopes generated during the oxidation of LDL and other lipoproteins, in aorta from apoE-/- mice. CONCLUSIONS: Although some limitations may reduce the applicability of results obtained in mice to humans, the apoE-/- mouse appears to be suitable for investigation of the role of apolipoproteins, enzymes and receptors involved in lipid metabolism, lipid oxidation, vascular cells and their secretory products as well as the possible role of antioxidants and gene-therapy in reducing atherogenesis.

Animals↗

Genetic modulation of oral anticoagulation with warfarin.

Cytochrome P450 CYP2C9 gene variants have been associated with hyperresponsiveness to small doses of warfarin and a higher bleeding complication rate. The aim of this study was to investigate whether CYP2C9 gene variants affect doses of drug prescribed to acquire the target anticoagulation intensity and the occurence of bleeding complications. In a cohort of 180 patients followed up at one specialized clinic from the start of the anticoagulation with warfarin, we have investigated whether CYP2C9 gene variants have affected doses of drug prescribed to acquire the target anticoagulation intensity and the incidence of bleeding complications. The adjusted dose required of warfarin was higher among patients with the CYP2C9*1 haplotype (5.6 mg) than those of patients carrying the CYP2C9*2 (4.7 mg; p = 0.007, Scheffé's test) or the CYP2C9*3 haplotype (4.0 mg; p <0.001, Scheffé's test). The occurrence of bleeding complications was more frequent among patients with the CYP2C9*2 and/or the CYP2C9*3 haplotype than in carriers of the CYP2C9*1 haplotype (OR: 2.57; 95% CI; 1.16-5.73). An interaction between the presence of local bleeding sources and the CYP2C9*2 and/or the CYP2C9*3 haplotype was observed (p <0.001). Patients with both local sites of potential bleeding and CYP2C9*2 and/or the CYP2C9*3 haplotype had the higher estimated risk of bleeding (OR: 12.81; 95% CI: 2.86-57.26). CYP2C9 gene variants modulate the anticoagulant effect of the dose of warfarin prescribed. The incidence of bleeding complications in CYP2C9*2 and CYP2C9*3 carriers was significantly higher than that in noncarriers and interacted with the presence of local bleeding sources.

Administration, Oral↗