Search PubMed⌕ Search

Biomedical subjects

U Cornelli

Publications and source records attributed to U Cornelli.

At least 19 recordsLinked to original sources

Bioavailability and antioxidant activity of some food supplements in men and women using the D-Roms test as a marker of oxidative stress.

Most antioxidants show contradictory behaviors because in the biological environment, for unpredictable reasons, they can become prooxidants. Recently, a new simple method to monitor oxidative stress in serum was developed. This test detects the derivatives of reactive oxygen metabolites (D-Roms). Hydroperoxides are converted into radicals that oxidize N,N-diethyl-para-phenylendiamine and that can be detected through spectrophotometric procedures as U.CARR. (Carratelli units). One U.CARR. corresponds to 0.8 mg/L hydrogen peroxide. In normal subjects U.CARR. values range from 250 to 300. Values outside this range indicate a modification of the prooxidant/antioxidant ratio. On the basis of this method, we tested three different formulas of antioxidants (F1, F2, F3) in 14 apparently healthy volunteers (11 men and 3 women). Formula 1 was composed of 5 mg zinc, 48 microg selenium, 400 microg vitamin A (as retinol acetate), 50 microg beta-carotene, 15 mg vitamin E (as dl-alpha-tocopheryl acetate) and 10 mg L-cysteine. Formula 2 was composed of 30 mg bioflavonoids from citrus, 30 mg vitamin C (as L-ascorbic acid), 10 mg coenzyme Q(10) and 1 mg vitamin B-6 (as pyridoxine hydrochloride). Formula 3 was composed of Formula 1 plus Formula 2. Each formula was prepared in dry capsules (formulation D1, D2, D3) or in a fluid form (formulation P1, P2, P3). Each formulation was administered for 1 wk in a crossover design. A 15% deviation of U.CARR. levels was chosen as the cut-off value for a significant change in oxidative stress. Formulas F1 and F3 reduced mean U.CARR. levels in most of the treated subjects (t test, P < 0.05), whereas F2 was not active. Fluid formulations were more active than dry formulations (chi(2) test, P < 0.05). In some cases, a slight increase in oxidative stress was detected. These minimal increases were not related to any particular antioxidant formula. In one subject only, the administration of the dry formulation (D1), increased oxidative stress to a level that reached the cut-off value. In conclusion, when antioxidants are taken in combination at low dosages they reduce oxidative stress, and little relevant prooxidant activity is detectable.

Adult↗

Oxygen-free radical decrease in hypertensive patients treated with lercanidipine.

BACKGROUND: The relationship between oxidative stress, lipoproteins, cardiovascular risk factors and vascular disease progression has recently attracted fresh attention due to the possibility of measuring free radicals (FRs). The aim of this study was to evaluate blood plasma variations in oxygen FRs in hypertensive patients treated with lercanidipine, a drug acting on blood pressure and microcirculation. METHODS: Twenty-two patients with moderate hypertension (M:F=12:10; age=52) and no vascular disease (evaluated by high-resolution ultrasound) were treated for 24 weeks with Lercanidipine (10 mg/day or 20 mg/day if BP values did not decrease at least 15 percent after four weeks of treatment). BP was measured at inclusion and after 4, 8, 12 and 24 weeks of treatment. FRs measurements (using the D-Roms test) were made at inclusion, at the 8th, 12th and 24th week. RESULTS: All patients completed the treatment which was well tolerated and without side effects. Systolic and diastolic BP decreased after 8, 12 (p<0.05) and 24 weeks (at 24 weeks systolic pressure was decreased by 21.1 percent, and diastolic by 11.1 percent; p<0.02). FRs levels progressively decreased from 541 Carr Units (SD 54) at inclusion to 411 (SD 56) at eight weeks (p<0.05), to 401 (SD 35) (p<0.05) at 12 weeks and finally to 398 (SD 33), (p<0.02) at 24 weeks of treatment (72.2 percent of the initial value). CONCLUSIONS: The possibility of measuring FRs in vivo with a simple, inexpensive test allows the identification of subjects with a high level of oxidative stress, and the monitoring of the effects of treatments. Lercanidipine, acting on blood pressure, on the microcirculation and decreasing oxidative stress and Frs plasma levels may effectively decrease the rate of progression of cardiovascular diseases offering the advantage of an increased level of protection in patients with high levels of oxidative stress.

Adult↗

Nomograms used to define the short-term treatment with PGE(1) in patients with intermittent claudication and critical ischemia. The ORACL.E (Occlusion Revascularization in the Atherosclerotic Critical Limb) Study Group. The European Study.

Infusional, cyclic PGE1 treatment is effective in patients with intermittent claudication and critical limb ischemia (CLI). One of the problems related to chronic PGE1 treatment in vascular diseases due to atherosclerosis is to evaluate the variations of clinical conditions due to treatment in order to establish the number of cycles per year or per period (in severe vascular disease reevaluation of patients should be more frequent) needed to achieve clinical improvement. In a preliminary pilot study a group of 150 patients (mean age 67+/-12 years) with intermittent claudication (walking range from 0 to 500 m) and a group of 100 patients with CLI (45% with rest pain, and 55% gangrene; mean age 68 +/-11 years) the number of PGE1 cycles according to the short-term protocol (STP) needed to produce significant clinical improvement was preliminarily evaluated. Considering these preliminary observations, the investigators established a research plan useful to produce nomograms indicating the number of cycles of PGE1-STP per year needed to improve the clinical condition (both in intermittent claudication and CLI). A significant clinical improvement was arbitrarily defined as the increase of at least 35% in walking distance (on treadmill) and/or the disappearance of signs and symptoms of critical ischemia in 6 months of treatment in at least 75% of the treated patients. With consideration of the results obtained with the preliminary nomograms a larger validation of the nomograms is now advisable. A cost-effectiveness analysis is also useful to define the efficacy of treatment on the basis of its costs. The publication of this report in two angiological journals (Angeiologie and Angiology) will open the research on nomograms to all centers willing to collaborate to the study. The data are being collected in the ORACL.E database and will be analyzed within 12 months after the publication of this report.

Aged↗

PGE(1) treatment of severe intermittent claudication (short-term versus long-term, associated with exercise)--efficacy and costs in a 20-week, randomized trial.

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe intermittent claudication was studied comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 980 patients (883 completed the study) with an average total walking distance of 85.5 +/-10 m (range 22-119). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 microg PGE1, 5 days each week for 4 weeks. In phase 3 (4-week interval period) PGE1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP phase 2 treatment was performed in 2 days by a 2-hour infusion (first day: morning 20 microg, afternoon 40 microg; second day morning and afternoon 60 microg). The reduced dosage was used only at the first cycle (week 0) to evaluate tolerability or side effects. Full dosage (60 microg bid) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks and at 20 weeks in the STP more than in the LTP group. At 4 weeks the variation (increase) in pain-free walking (PFWD) was 167.8% (of the initial value) in the LTP group and 185% in the STP group (p<0.05). At 4 weeks the variation (increase) in total walking distance (TWD) was 227.6% of the initial value in the LTP group and 289% in the STP group (p<0.05). At 20 weeks the increase in PFWD was 496% of the initial value in the LTP group vs 643% in the STP group (147% difference; p<0.02). The increase in TWD was 368% in the LTP group and 529% in the STP group (161% difference; p<0.02). In both groups there was a significant increase in PFWD and TWD at 4 and 20 weeks, but results obtained with STP are better considering both walking distances. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 6.3% of the treated subjects in the LTP and 3% in the STP. Average cost of LTP was 6,664 Euro; for STP the average costs was approximately 1,820 E. The cost to achieve an improvement in walking distance of 1 m was 45.8 E with the LTP and 8.5 E with the STP (18% of the LTP cost; p<0.02). For an average 100% increase in walking distance the LTP cost was 1,989 E vs. 421 E with STP (p<0.02). Between-group analysis favors STP considering walking distance and costs. Results indicate good efficacy and tolerability of PGE, treatment. With STP less time is spent in infusion and more in the exercise program. STP reduces costs, speeds rehabilitation, and may be easily used in a larger number of nonspecialized units.

Aged↗

A simple test to monitor oxidative stress.

BACKGROUND: The role of oxygen free radicals is considered important in the development of cardiovascular disease. However, until recently determination of free radicals plasma levels and the effect of antioxidant therapy on these levels has been difficult. The aim of the study was to determine the oxidative stress and the effect of the antioxidant compound AR(D) Stenovit on this stress in normal subjects and patients with intermittent claudication after oral administration for one week. METHODS: A portable, free radicals (FRs) determination system (D-Roms test, Diacron, Grosseto, Italy) was used. This test is based on the ability of transition metals to catalyse in the presence of peroxides with formation of FRs which are trapped by an alchilamine. The alchilamine reacts forming a coloured radical detectable at 505 nm. The reagents utilised are the cromogen (R1, an alchilamine) and a pH 4.8 buffer (R2). Ten microl of hemolysis-free serum are to 1 ml of R2 and to 10 microl of R1. The sample is mixed, incubated (1 min; 37 degrees C) and read for optical density. After another minute, the sample is read again. The average delta A/min is multiplied by a K factor and calculated using serum with defined value. RESULTS: In normal subjects the mean (+/-SD) levels of free radicals were 312+/-49 U.CARR (Carratelli units) before treatment and 218+/-33 U.CARR after treatment (p<0.05). A decrease of at least 10% was detected in every subject. In patients with peripheral vascular disease the mean (+/-SD) levels of free radicals were 404+/-42 U.CARR before treatment and 278+/-33 U.CARR after treatment (p<0.02). A decrease of at least 15% was detected in every patient (medium value 31%). CONCLUSIONS: The D-Roms test provides a simple, inexpensive and practical method to identify subjects with a high level of oxidative stress and to demonstrate the effect of treatment. The compound AR(D) Stenovit is effective in reducing circulating free radicals. Its action on the progression of atherosclerotic disease should be assessed in future studies.

Adult↗

Human pharmacokinetics of low molecular weight heparins.

Pharmacokinetic parameters of low molecular weight heparins (LMWHs) are commonly determined by quantifying the biological activity. Such pharmacodynamic determinations should be extrapolated with care to provide pharmacokinetic information. Direct comparisons should only be drawn between LMWHs given at the same dose, determined by the same test. This is especially important since different tests estimate potency, bioavailability, and duration differently. There is a strong correlation between the ratio of anti-Xa:anti-IIa activities determined in vitro and mean residence time in vivo. Each LMWH has a characteristic pharmacokinetic and pharmacodynamic profile and cannot be considered bioequivalent either at doses recommended for prophylaxis or at anti-Xa adjusted doses. These conclusions emphasize that LMWHs are not interchangeable drugs and recommendations for drug dosing should be made based on pharmacological data available for each LMWH.

Animals↗

Treatment of severe intermittent claudication with PGE1--a short-term vs a long-term infusion plan--a 20 week, European randomized trial--analysis of efficacy and costs.

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe intermittent claudication was studied by comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 109 patients (96 completed the study) with an average total walking distance of 65.5 +/- 8 m (range 20-109). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 microg PGE1, 5 days each week for 4 weeks). In phase 3 (4-week interval period) PGE1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP, phase 2 treatment was performed in 2 days by a 2-hour infusion (1st day: morning 20 microg, afternoon 40 microg; 2nd day morning and afternoon 60 microg). The reduced dosage was used only at the first cycle (week 0) to evaluate reduced tolerability or side effects. Full dosage (60 microg b.i.d.) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of the 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks (101.5% in STP vs 78.3% in LTP), at 8 weeks (260.9% STP vs 107.3% LTP), and at 20 weeks (351% STP vs 242% LTP). Comparable increases in pain-free walking distance were observed in the two groups. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 7% of the treated subjects in the LTP and 5% in the STP. Average cost of LTP was approximately 6,588 ECU; for STP the average cost was approximately 1,881 ECU. The cost to achieve an improvement in walking distance of 1 m was 35.6 ECU with the LTP and 9.45 ECU with the STP (26% of the LTP cost; p<0.02). For an average 100% increase in walking distance the LTP cost was 1,937 ECU vs 550 ECU with STP (p<0.02). The cost of PGE1 (including infusion and operative costs) was 25% of the total cost for LTP (24.9% for STP). In summary, between-group-analysis favors STP, in terms of walking distance and costs. Results indicate good efficacy and tolerability of PGE1 treatment. With STP less time is spent in infusion and more can be spent in the exercise program. STP reduces costs, speeds up rehabilitation, and may be used in a larger number of nonspecialized units available to follow the protocol.

Alprostadil↗

Pharmacokinetics of GM1 ganglioside following parenteral administration.

The pharmacokinetic parameters of monosialotetrahexosylganglioside (GM1) have been determined in healthy volunteers at 3 dose levels: 100, 200, 300 mg. Each dose was administered to separate groups of 12 volunteers. GM1 levels were determined in plasma, urine, and faeces by a method based on the property of the cholera toxin beta subunit to react specifically with GM1 ganglioside. A non-compartmental model was applied to determine standard pharmacokinetic parameters. The average AUC increased with dose (1002 +/- 121.2, 1306 +/- 146.1, 3155 +/- 121.6 micrograms mL-1 h after 100, 200, 300 mg, respectively). Plasma clearance was less than 3 mL min-1 and the distribution volume was close to the plasma volume (on average between 4.3 and 7.2 L). Mean residence time was about 43 h for all doses. GM1 was not detected in urine, while in faeces the amount of GM1 determined was similar to the baseline values obtained before dosing.

Adult↗

[A multicenter study of defibrotide in the prevention of deep venous thrombosis. Final results].

In an open multicenter comparative study aimed at the evaluation of the efficacy of defibrotide and calcium heparin in the prophylaxis of postoperative deep vein thrombosis (DVT) and pulmonary embolism (PE) an evaluation has been made on 4810 patients. 2810 patients received defibrotide (800 mg/die: 400 mg b.i.d. or 200 mg q.i.d. by IV route); 2000 patients received calcium heparin (500 IU b.i.d. or t.i.d. by SC route) till the 7th post-operative day. The diagnosis of DVT or pulmonary embolism (PE) was made according to clinical routine criteria. The incidence of DVT has been 33/2810 (1.17%) in the defibrotide group and 47/2000 (2.35%) in the heparin group (chi 2 p = 0.002), while the cases of suspected or ascertained PE have been respectively 15/2810 (0.53%) and 23/2000 (1.15%) (p = 0.025). The post-operative course was totally normal in both groups; no significant adverse reactions were noticed. The obtained results suggest the effectiveness of defibrotide as an alternative to heparin in the prevention of post-operative DVT.

Adult↗

Antithrombotic drugs in pelvic surgery.

From the discussion, it is clear that several agents are available for the prophylactic antithrombotic management of pelvic surgery. Unlike other surgical procedures, the interventions are performed in women with many physiologic and pathologic predisposing factors. There is an increased risk of bleeding in these patients and the selection of an antithrombotic drug with a high safety to efficacy ratio is imperative. Although the introduction of newer drugs, such as defibrotide and low molecular weight heparins, provides certain advantages over the conventional drugs, large-scale prospective clinical trials are required to justify their use. Combination therapy will also be a useful and more effective approach in the management of pelvic surgical patients. However, optimization of dosage and an empiric determination of the safety and efficacy of different drugs used in combination will have to be made. Newer therapeutic agents will have a direct impact in this area in coming years. The practicing clinician should keep an open mind to provide better patient care.

Female↗

Lack of effect of a single-dose of sulglicotide on the bioavailability of diclofenac.

The bioavailability of diclofenac (D) was assessed in 12 healthy volunteers treated orally with single doses of 100 mg (retard formulation) and subsequently retreated with the same dose of (D) plus sulglicotide (S) 200 mg. (D) blood levels were measured by GLC in samples collected after 1, 2, 4, 6, 8, 12, 24 h. No relevant difference was seen in (D) bioavailability after (S) administration; after 8 h plasma levels of (D) were slightly higher after (S) (p less than 0.05), but this difference can be considered incidental only. Thus, sulglicotide does not interfere with the bioavailability of diclofenac, and can be administered concurrently with the latter to prevent possible gastric injury by the antiinflammatory drug.

Adult↗

Effect of methyldopa on prolactin serum concentration. Comparison between normal and sustained-release formulations.

In a group of ten hypertensive patients, the effects of methyldopa administration in two different formulations on serum prolactin (PRL) were studied. A single oral dose of normal release methyldopa significantly increased serum prolactin levels, peak concentrations occurring 3 to 6 h after drug administration. On the contrary, administration of sustained release methyldopa at the same dose was only followed by slight and not significant fluctuations in prolactin plasma levels. Both formulations produced a significant decrease of systolic and diastolic blood pressures, without significant differences between sustained and normal release methyldopa effects.

Adult↗

[Defibrotide in the prevention of deep venous thrombosis in general surgery. Preliminary results of a multicenter study].

In an open multicenter comparative study aimed at the evaluation of the efficacy of defibrotide in the prophylaxis of postsurgical deep vein thromboses (DVT) an ad interim evaluation has been made on 2626 patients thus far enrolled. 1323 had received defibrotide (200 mg q.i.d. by IV route from day -1 to day +7th postoperative), 941 calcium heparin (5000 IU b.i.d. or t.i.d. by SC route from day 0 to day +7 postoperative) and 362 other treatments (antiaggregating agents, placebo or no therapy). This group has not been included in the final evaluation, due to its limited size. The diagnosis of DVT or pulmonary embolism (PE) was made according to clinical routinary criteria. The incidence of DTV has been 15/1323 (1.13%) in the defibrotide group and 21/941 (2.23%) in the heparin group (chi-square, p = 0.056) while the cases of suspected or ascertained PE have been respectively 3/1323 (0.22%) and 10/941 (1.06%) (p = 0.02). The incidence of adverse effects with defibrotide was less than 1%; occasional cases of increased serum transaminase levels were seen with heparin. These preliminary results supports the effectiveness of defibrotide in the prevention of post-surgery DVT, its effects being similar or more prominent than those of calcium heparin, currently regarded as the standard medication.

Adult↗