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Carlo Giansante

Publications and source records attributed to Carlo Giansante.

11 recordsLinked to original sources
PubMed2006

MMP-9 microsatellite polymorphism and susceptibility to carotid arteries atherosclerosis.

OBJECTIVE: The aims of this study were to compare a microsatellite polymorphism (PM) of matrix metalloproteinase (MMP)-9 in patients with carotid atherosclerosis and control population, and to assess the relationship between this PM and plaque structure. METHODS AND RESULTS: One hundred fifty patients referring to vascular diagnostic centers for suspected carotid atherosclerosis (at ultrasound examination: 110 positive, 40 negative) and controls (n=110) have been genotyped for MMP-9 PM. After controlling for risk factors, allelic and genotype frequencies were significantly different among the groups, with significant prevalence of long microsatellites in patients with carotid atherosclerosis. Long microsatellites (settled as 22 to 27 repeats) were associated with carotid atherosclerosis (odds ratio [OR], 5.2; 95% confidence interval [CI], 2.9 to 9.2), compared with controls; an independent case control study on patients with coronary atherosclerosis confirmed such result. Binary logistic regression showed that hypertension, long microsatellites in MMP-9 PM and smoking habits were variables accounting for the difference between ultrasound-positive patients and controls. Long microsatellites were also associated to plaques with thin fibrous cap and echolucent core (OR, 13.1; 95% CI, 1.6 to 100). These alleles were slightly more represented in female patients (chi2 test=0.019; OR, 2.7; 95% CI, 1.2 to 6) but not associated with other risk factors. Plasma MMP-9 levels were related neither to MMP-9 PM nor to plaque type, and were related to gender and extension of atherosclerosis in carotid arteries. CONCLUSIONS: The number of repeats (> or =22 CA) in the microsatellite of MMP-9 promoter, but not MMP-9 plasma levels, is associated to carotid atherosclerosis and particularly to plaques with a thin fibrous cap.

Carotid Artery Diseases↗
PubMed2006

Host-guest complexes between an aromatic molecular tweezer and symmetric and unsymmetric dendrimers with a 4,4'-bipyridinium core.

We have investigated the spectroscopic and electrochemical behavior of symmetric and unsymmetric first-, second-, and third-generation dendrimers comprising an electron-acceptor 4,4'-bipyridinium core (viologen type) and electron-donor 1,3-dimethyleneoxybenzene (Fréchet-type) dendrons. The quite strong fluorescence of the symmetrically and unsymmetrically disubstituted 1,3-dimethyleneoxybenzene units of the dendrons is completely quenched as a result of donor-acceptor interactions that are also evidenced by a low-energy tail in the absorption spectrum. In dichloromethane solution, the 4,4'-bipyridinium cores of the investigated dendrimers are hosted by a molecular tweezer comprising a naphthalene and four benzene components bridged by four methylene units. Host-guest formation causes the quenching of the tweezer fluorescence. The association constants, as measured from fluorescence and (1)H NMR titration plots, (i) are of the order of 10(4) M(-1), (ii) decrease on increasing dendrimer generation, and (iii) are slightly larger for the unsymmetric than for the symmetric dendrimer of the same generation. The analysis of the complexation-induced shifts of the temperature-dependent (1)H NMR signals of the host and guest protons confirms that the bipyridinium core is positioned inside the tweezer cavity and allows the conclusions that (i) shuttling of the tweezer from one to the other pyridinium ring is fast (DeltaG < 10 kcal/mol), (ii) in the case of the unsymmetric dendrimers, the less substituted pyridinium ring is preferentially complexed in apolar solvents, and (iii) complexation of the 4,4'-bipyridinium core proceeds by clipping for the symmetric dendrimers and by threading in the case of unsymmetric ones. Host-guest formation causes a displacement of the first reduction wave of the 4,4'-bipyridinium unit toward more negative potential values, whereas the second reduction wave is unaffected. These results show that the host-guest complexes between the tweezer and the dendrimers are stabilized by electron donor-acceptor interactions and can be reversibly assembled/disassembled by electrochemical stimulation.

Journal Article↗
PubMed2005

MMP-9 microsatellite polymorphism: association with the progression of intima-media thickening and constrictive remodeling of carotid atherosclerotic plaques.

Intima-media thickening (IMT) of carotid arteries and constrictive remodeling (CR) of atherosclerotic plaques are vascular pathologic characteristics that precede the onset of vascular events. SMC migration and proliferation are linked both to IMT and CR and are matrix metalloproteinase 9 (MMP-9) dependent. A genetic polymorphism (PM) of MMP-9, a CA (13-27) microsatellite in the promoter region, which accounts for differential expression of MMP-9, could be linked to progression of IMT and CR. Progression of IMT and CR of plaques in carotid arteries were studied in 55 consecutive patients with a 12-18 months follow-up. All patients were genotyped for MMP-9 PM. A positive linear relationship between the number of repeats and the progression of IMT (P=0.028) as well as of CR (P=0.018) was found. The analogous relationship was obtained when only the allele with longer microsatellite was considered. Carriers of more than 20 repeats in one allele showed faster both IMT growth (P=0.045) and stenosis progressions of plaques (P=0.019). In multivariate analysis, age, dyslipidemia, and MMP-9 PM were determinants of IMT progression, while MMP-9 PM was the only one of CR. In conclusion, the high number of CA repeats in MMP-9 promoter is positively correlated with faster IMT and CR progression.

Aged↗
PubMed2005

MMP-9 microsatellite polymorphism and susceptibility to exudative form of age-related macular degeneration.

PURPOSE: To assess if a polymorphism (PM) of the microsatellite (CA(13-27)) in the promoter region of Matrix Metalloproteinase 9 (MMP-9) was associated with the exudative form of age-related macular degeneration (AMD) and to its risk factors. METHODS: In 107 patients with AMD (AMD Group) and 223 age- and gender-matched controls (Control Group) with cataract, demographic, clinical data, and MMP-9 PM have been compared. RESULTS: The comparison of allelic frequencies showed a different pattern of CA repeats between AMD and Control Group (P < 0.00005), in particular the prevalence of longer microsatellites (> or = 22 CA repeats) was higher in AMD than in Control Group (O.R. 2.49, 95% CI 1.71-3.37, P < 0.001). Analyses of genetic frequencies gave similar results. Logistic regression confirmed that 22 or more CA repeats are associated to AMD. The only association between MMP-9 PM and other risk factors for AMD was with BMI (Spearman's R = 0.298, P < 0.00005): all patients with both microsatellites > or = 22 CA repeats were overweight or obese (chi2 test P < 0.0005, compared to other genotypes). CONCLUSIONS: Longer microsatellites in the promoter of MMP-9 are associated to the exudative form of AMD and to body mass index, a well-known risk factor for the disease.

Aged↗
PubMed2004

MMP-9 microsatellite polymorphism and multiple sclerosis.

A polymorphism (PM) in the microsatellite of the promoter region of matrix metalloproteinase 9 (MMP-9), modulating its expression, could play a role in susceptibility to multiple sclerosis (MS). MMP-9 PM was determined in 95 patients with MS (MS Group) and 95 age- and sex-matched controls (Control Group). Comparison of allelic frequencies showed that a higher number of CA repeats characterized the MS group (P<0.0001) and prevalence of carriers of > or =22 CA repeats was higher in the MS than in the Control Group (OR 3.4, 95% CI: 1.7-6.8, P<0.0001). An earlier age at disease onset was a characteristic of patients with >22 CA repeats (33+/-10 vs. 28+/-10, P=0.027). No differences were found in the main MRI parameters.

Adolescent↗
PubMed2004

[Ximelagatran: a promising new drug for oral anticoagulation].

Ximelagatran is the first orally available direct thrombin inhibitor. Ximelagatran is a pro-drug with an antithrombotic effect comparable to that of warfarin. Clinical studies have demonstrated that ximelagatran is as effective as warfarin in the prevention of deep-vein thrombosis, of stroke in patients with nonvalvular atrial fibrillation, and of the adverse cardiovascular events in patients with recent myocardial infarction. Ximelagatran can be administered without any need of laboratory test.

Administration, Oral↗
PubMed2004

[New perspectives for anticoagulation in non-rheumatic atrial fibrillation: oral antithrombins].

Non-rheumatic atrial fibrillation (NRAF) is one among the major public health problems, because it is associated with a high incidence of stroke or systemic thromboembolism. Warfarin significantly reduces cerebral/systemic events mainly in high-risk patients; unfortunately such drug is often as well under-used in eligible patients as under-dosed in treated patients. Traditional therapy with oral anticoagulants has several disadvatages: narrow therapeutic window, and often unpredictable dose-response so that frequent monitoring of the INR is required. It is therefore crucial that patients preferences and education be integrated into the decision-making process. Physicians often underprescribe oral anticoagulants since they perceive the risk of major bleeding as unacceptable because of some well known risk factors (e.g. previous bleedings, severe hypertension), and of qualms about drug interactions or alleged poor compliance. Therefore, the development of easy-to-use antithrombotic agents is still a challenge. New agents such as oral direct thrombin inhibitors are going to hold the promise for the next future. Ximelagatran is an orally active small molecule; being the first new oral anticoagulant used in large clinical trials. This molecule has many advantages in comparison to warfarin, such as the rapid onset/offset of action, the fixed oral dose, the no need of dose adjustment or of anticoagulation monitoring, as well the lack of food/alcohol intake interference as of drug interactions. The SPORTIF III and V trials have shown that ximelagatran is not inferior to warfarin in the prevention of strokes in patients with NRAF (both persistent and paroxysmal), but a side effect--consisting in the significant elevation of liver enzymes (> 3 times the upper limit of normal) in 6% of patients--was found. Further randomized trials are clearly needed, while current data suggest that ximelagatran will be able to represent a future viable therapeutic option for prevention of thromboembolism in patients with NRAF, offering huge advantages with respect to classic oral anticoagulants.

Administration, Oral↗
PubMed2003

[Control of anticoagulant therapy with portable prothrombin time device in patients with mechanical heart valve prostheses: two-year follow-up].

BACKGROUND: Monitoring patients on oral anticoagulation is essential to prevent haemorrhage and recurrent thrombosis, but it is still difficult. We studied a group of 348 patients with mechanical heart valve prostheses to verify whether the use of a new portable prothrombin time device might improve the management of oral anticoagulant therapy. METHODS AND MATERIAL: We used a new portable prothrombin time device to check the anticoagulation therapy in a group of 348 patients with mechanical heart valve prostheses to validate its results by comparing to routine I.N.R. determinations (28 pts) and verify its user-friendliness by a face-to-face interview. Furthermore, the incidence of haemorrhagic and thromboembolic events has been studied by a two-year follow-up. RESULTS: Pearson correlation indicated an R2 = 0.9 between I.N.R. values determined by routine or by a new portable prothrombin time device. All patients agreed to replace the routine I.N.R. determinations with those by the new procedure, particularly female, young and those with usually difficult blood collections. During the two-year follow-up period, 21 haemorrhagic (2.6/100/patients/year) and 5 thromboembolic events (0.6/100/patients/year) occurred; but neither replaced valves' thrombi nor fatal events were found out. CONCLUSIONS: I.N.R.s determined using a new portable prothrombin time device are convincing as routine determinations. Such new procedure improves the quality of life, and the therapeutical range of anticoagulation is maintained safer and longer than by routine determinations. These results suggest that the control of anticoagulation in patients to a set I.N.R. therapeutic range is improved by using portable prothrombin time device in expert anticoagulation clinics, such improvement may result in reducing mortality as well as morbidity in patients treated with oral anticoagulants.

Anticoagulants↗
PubMed2002

Interleukin-1 receptor antagonist: a sensitive marker of instability in patients with coronary artery disease.

BACKGROUND: Increased plasma levels of acute phase reactants are correlated with acute coronary syndromes and increased risk of in-hospital events. Interleukin-1 receptor antagonist (IL-1Ra) modulates the activity of IL-1, a cytokine associated with inflammatory response; we have prospectively investigated whether detection of increased levels of IL-1Ra in patients may be useful in the characterization of coronary syndromes. METHODS: Plasma levels of IL-1Ra were measured in 118 consecutive patients undergoing coronary angiography with a clinical diagnosis of recent unstable angina (N = 57), chronic stable angina (N = 49) or atypical chest pain (N = 12). RESULTS: Angiography showed significant coronary disease in the first two groups and was normal in the latter group. Patients with unstable angina had significantly higher levels of IL-1Ra than stable patients [158 (110-224) vs 108 (95-154) pg/ml, P = 0.002] and individuals with chest pain and normal coronary angiogram [110 (97-123) pg/ml, P: = 0.038]. In contrast, while C-reactive protein levels were significantly higher in patients with stable and unstable angina vs those without coronary disease (0.29 vs 0.06 mg/dl, P: = 0.022), they did not discriminate between stable and unstable angina patients (0.22 vs 0.32 mg/dl, P: = 0.66). CONCLUSIONS: These results indicate that IL-1Ra may be a sensitive marker of clinical instability in patients with coronary artery disease.

Aged↗