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Patrizia Brizzi

Publications and source records attributed to Patrizia Brizzi.

7 recordsLinked to original sources
PubMed2004

Autoantibodies against oxidized low-density lipoprotein (ox-LDL) and LDL oxidation status.

Oxidized low-density lipoproteins (ox-LDLs) and their autoantibodies (OLAB) are involved in the development of atherosclerosis in animal models, but their role in humans is still not clear. For this reason we studied 54 patients with beta-thalassemia major (TM), as a model of chronically low circulating LDLs with a high level of oxidation; 44 patients with primary hypercholesterolemia, as model of chronically high circulating LDLs; 24 type 2 diabetic mellitus patients (T2DM) before and after 3 months of atorvastatin treatment (20 mg/day), as a model of acute changes in circulating LDLs; and 41 normolipidemic subjects as a control group. ox-LDLs were measured by the determination of baseline diene concentration in the plasma LDL lipidic fraction after 12 hours fasting and were expressed as the amount of conjugated dienes/ liter (BDC/I) or BDC/LDL-cholesterol (LDL-C), which indicate respectively LDL oxidation degree and status. OLAB were determined using an enzyme immunoassay and related to LDL oxidation degree (BDC/I). In TM, BDC/I was lower, while BDC/LDL-C was significantly higher, compared to both hypercholesterolemia and normolipidemic subjects. Patients with hypercholesterolemia had higher BDC/I, but lower BDC/LDL-C and OLAB/BDC-I, than normolipidemic subjects. In T2DM patients at diet, BDC/LDL-C and OLAB/BDC-I were lower than in normolipidemic subjects. After 3 months of atorvastatin treatment, BDC/ LDL-C and OLAB/BDC-I ratios increased. When all patients were evaluated together, a significant inverse correlation was evident between OLAB and either LDL or BDC/I. Our findings suggest that a relationship between OLAB titer and oxidation indices (BDC/I and BDC/LDL-C) does exist and we may speculate that an increase in OLAB/BDC-I ratio might be protective against the risk of atherosclerosis.

Adolescent↗
PubMed2003

Effect of ovarian stimulation on plasma lipid and apolipoprotein concentrations in a population of infertile women undergoing IVF/embryo transfer.

Twenty consecutive infertile women (mean age +/- SD, 36.9 +/- 5.4 years) undergoing ovarian stimulation with recombinant follicle stimulating hormone (rFSH) were recruited. Serial measurements of plasma total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), apolipoprotein A1 (ApoA1), apolipoprotein B (Apo-B), lipoprotein(a) (Lp(a)), oestradiol and progesterone were performed on day 3 before starting ovarian stimulation, on the day of human chorionic gonadotrophin (HCG) administration and on day 15 after HCG administration, respectively. The relationship between lipid and apolipoprotein concentrations and serum oestradiol and progesterone concentrations was sought. All women completed the ovarian stimulation protocol successfully. Plasma concentrations of HDL-C and Apo-A1 were significantly raised on the day of HCG administration and then returned to baseline values within 2 weeks. LDL-C, TG, Apo-B and Lp(a) were significantly increased on day 15 after HCG administration. Lp(a) variation between the first sample and the third sample correlated positively with serum progesterone concentrations (r = 0.472, P < 0.04). No other significant correlations were found between lipid and apolipoprotein variations and either oestradiol or progesterone concentrations. It was concluded that an increase of plasma lipid and apolipoprotein concentrations deserves particular consideration and all women undergoing ovarian stimulation should be monitored for long-term atherogenic and thrombogenic risks.

Adult↗
PubMed2003

Plasma lipid composition and LDL oxidation.

Low-density lipoprotein (LDL) oxidation in vivo depends on lipid composition and on plasma antioxidant status. The aim of our study was to investigate the relationship between plasma lipid composition and LDL oxidation and, in particular, to explore whether LDL-cholesterol/triglycerides ratio (LDL-C/TG) and LDL-cholesterol/high-density lipoprotein (HDL)-cholesterol ratio (LDL-C/HDL-C) can be used as predictive parameters of LDL oxidation in vivo. In 87 volunteers over a wide range of age plasma lipids and LDL oxidation were studied. Blood was collected after 12 h overnight fast. LDL oxidation was estimated by the level of conjugated diene (BDC) in the lipid fraction isolated from plasma after gradient ultra-centrifugation. The results were expressed as micromol/l (BDC/l) to evaluate the level of oxidized LDL, and as nmol of BDC for mg of LDL-cholesterol (BDC/LDL-C) for the evaluation of LDL oxidation degree. BDC/l correlated significantly with age, total and LDL-C, apolipoprotein B and TG, while BDC/LDL-C negatively correlated with total cholesterol, apolipoprotein B, LDL/TG and LDL/HDL ratios. Age of subjects significantly correlated with total and LDL-C and apolipoprotein B. TG have a significant inverse correlation with HDL-C. Our results support the hypothesis that among the several factors involved in LDL oxidation the most important determinants are LDL/TG. Plasma triglycerides appear to be very important even when circulating cholesterol levels are within normal limits. Moreover, we found that the LDL/HDL ratio is also very important with regard to the putative protective role of HDL against LDL oxidation in vivo. In conclusion, plasma lipid parameters must be evaluated not only for their absolute values but also for their mutual ratios as expression of plasma lipid homeostasis. Both LDL/TG and LDL/HDL ratios can be used as predictive parameters of in vivo LDL oxidation.

Adolescent↗
PubMed2002

The Trp64Arg beta3-adrenergic receptor amino acid variant confers increased sensitivity to the pressor effects of noradrenaline in Sardinian subjects.

The beta(3)-adrenergic receptor (beta(3)AR) plays a critical role in lipid metabolism, and thus alterations in its function may be involved in the metabolic syndrome. Indeed, we have found previously that the Trp64Arg amino acid variant of the beta(3)AR is associated with hypertension and higher serum triacylglycerol levels in the Sardinian population. The aim of the present study was to evaluate the effect of the Trp64Arg beta(3)AR variant on the regulation of triacylglycerol levels and blood pressure during the exogenous infusion of noradrenaline. We studied groups of non-diabetic normotensive subjects: eight with the wild-type Trp64Trp beta(3)AR and eight with the Trp64Arg variant. The subjects each received, on two different days (randomized, double-blind fashion), a 4 h infusion of either noradrenaline (0.147 nmol.min(-1).kg(-1)) or Emagel (subjects had fasted for at least 12 h). The only available subject with a homozygous mutant Arg64Arg beta(3)AR was also studied. Blood pressure was measured every 10 min using a sphygmomanometer, and blood samples were taken every 30 min from the contralateral vein for biochemical determinations. After a 4 h noradrenaline infusion, significant increases in diastolic blood pressure (from 83+/-2 to 91+/-3 mmHg; P <0.01) and serum triacylglycerol levels (from 1.69+/-0.4 to 1.79+/-0.6 mmol/l; P <0.05) were observed compared with basal values in subjects with the Trp64Arg beta(3)AR variant, whereas subjects with the Trp64Trp beta(3)AR did not show any significant change over the infusion period. Glycaemia had increased significantly only at the end of the first 1 h of infusion in subjects with the Trp64Arg variant (from 5.0+/-0.1 to 5.8+/-0.3 mmol/l; P <0.05), with no significantly different behaviour compared with those subjects with the Trp64Trp beta(3)AR during the remaining infusion period. The effects of noradrenaline infusion were more marked in the subject with the Arg64Arg variant. In conclusion, our data indicate that the Trp64Arg amino acid variant of the beta(3)AR confers increased sensitivity to the pressure effect of noradrenaline. Moreover, this variant also influences blood triacylglycerol levels and, to a degree, glucose metabolism.

Adult↗
PubMed2002

Oxidized LDL antibodies (OLAB) in patients with beta-thalassemia major.

Thalassemic (TM) patients are subjected to peroxidative tissue injury because of continuous blood transfusions. It has been documented that circulating LDL from TM patients show marked oxidative modification, that could represent an event leading to atherogenesis. We investigated in 75 beta-TM patients the levels of oxidized LDL antibody (OLAB) to asses their correlation with total cholesterol, LDL and HDL cholesterol, triglycerides Apo A-1 and Apo B. OLAB/mg chol-LDL is greater in TM patients than healthy controls (p<0.001). No correlation was found between OLAB and age, sex of patients, mean blood consumption, mean serum ferritin, mean transaminases, PT, PTT, and fibrinogen. A significant positive correlation was found between OLAB and triglycerides in TM patients (p<0.001). Also a significant correlation was found between OLAB/mg chol-LDL and level of triglycerides in TM patients, but not with total cholesterol, LDL and HDL chols, Apo A-1 and Apo B. On the contrary in the healthy controls this correlation between OLAB and OLAB/mg chol-LDL versus triglycerides was negative and not significant. High levels of OLAB/mg chol-LDL in patients with beta-thalassemia, in absence of evident signs of atherosclerosis, suggest some regulatory mechanisms on the lipid peroxidation which modulate the deposition of ox-LDL in the macrophages and support the hypothesis that both serum iron and triglycerides are involved in the pathogenesis of LDL oxidation.

Adolescent↗
PubMedDate not supplied

Duodenal switch without gastric resection: results and observations after 6 years.

BACKGROUND: The results on metabolic effects of the classical biliopancreatic diversion (BPD) have led us to investigate the operation without gastric resection, thus preserving stomach and pylorus, in patients who are not seriously obese but suffer from hypercholesterolemia, often associated with type 2 diabetes and hypertriglyceridemia. METHODS: Between 1996 and 1999, we performed the duodenal switch (DS) without gastric resection on 24 mildly obese patients. Mean preoperative BMI was 36.2 kg/m(2). 17 patients (70.8%) suffered from type 1 diabetes, 4 (16.6%) had impaired glucose tolerance, while the remainder had fasting hyperglycemia. In 20 patients (83.3%), hypercholesterolemia and alterations in lipid profile were present. Another 20 patients were taking drugs for arterial hypertension. The pluri-metabolic syndrome was present in 41.6% of patients. RESULTS: Mean follow-up was 4 years. BMI reduction and weight loss were not large. 2 patients who had severe longstanding diabetes type 2 needed a second operation of the classical BPD because of failure in improving diabetes. Another 2 patients were changed to classical BPD because of a relapsing chronic duodeno-ileal ulcer. The incidence of ileal ulcer was 29.1%. Regarding hypercholesterolemia, hypertrigliceridemia, and type 2 diabetes when there is a good pancreatic "reservoir", the operation seems effective in the long-term. Protein absorption is better than that obtained with the classical BPD. CONCLUSIONS: Our long-term results suggest that in carefully selected patients suffering from serious hypercholesterolemia or type 2 diabetes with insulin reserves still at an acceptable level, and with BMI 30-40, DS without gastric resection can be proposed as a surgical treatment for metabolic diseases but not for obesity.

Adult↗