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Biomedical subjects

A Conte

Publications and source records attributed to A Conte.

At least 109 records · Page 6Linked to original sources

[A retrospective study of 200 cases of lichen].

In this study the data on 200 patients affected by various features of lichen planus (LP) are reported. All subjects were in-patients of the Department of Dermatology, Bari, from 1973 to 1988. In 87% of cases the disease appeared as lichen tuber planus, and in 9% there was involvement of mucous membranes. Equal involvement of sex incidence has been found, and the patients were middle-aged (mean, 47 years). The lesion were not subsided in about 10% of cases. Associated fortuitous skin conditions were mainly alopecia areata and vitiligo. In addition, LP has been observed in association with diabetes (8%) and hepatic diseases (10%). These last values could appear relevant, but in our region, Apulia, both diabetes and hepatitis, and especially B-hepatitis, are very frequent diseases. Our clinical follow-up did not allow to consider LP as a symptom of other subsequent organic diseases.

Diabetes Complications↗

Urolithiasis inhibitors and calculus nucleation.

The possible inhibitors of heterogeneous nucleation were investigated. The effects of magnesium, pyrophosphate, citrate and Chondroitin Sulphate on calcium phosphate or uric acid heterogeneous nucleation of calcium oxalate were studied. It was found that whereas magnesium, pyrophosphate and citrate acted as effective inhibitors in the presence of calcium phosphate as heterogeneous nucleant, only chondroitin sulphate manifested important inhibitory effects when uric acid was the heterogeneous nucleant.

Calcium Oxalate↗

The relation between orthophosphate and pyrophosphate in normal subjects and in patients with urolithiasis.

In calcium lithiasis, inhibitors have a significant effect in reducing the crystallization process. This work evaluated orthophosphate in a group of patients with calcium oxalate lithiasis, and in a control group. The study of orthophosphate and pyrophosphate, showed differences between stone formers and the control group. These results could be attributed to a failure in the renal transformation of orthophosphate into pyrophosphate.

Diphosphates↗

On the relation between citrate and calcium in normal and stone-former subjects.

The aim of this work is to evaluate citrate in a group of patients with calcium oxalate urolithiasis and in a control group for detecting possible differences between the two groups. The mean urinary concentration in groups of stone-formers was found significantly lower than in the control group. Particularly interesting was the correlation study between citrate and calcium. It was found that patients with hypocitraturia have hypercalciuria. Thus, it is particularly interesting to point out the importance of citrate in preventing the risk of lithiasis in stone-formers studied by us.

Adult↗

Investigation of GAGS on 24-hour and 2-hour urines from calcium oxalate stone formers and healthy subjects.

The role of urinary glycosaminoglycans (GAGS) in calcium oxalate lithiasis is of great interest in urologic research. It has been claimed that GAGS are important inhibitors of calcium oxalate crystal growth and aggregation. The aim of this paper is to evaluate GAGS excretion and concentration in two groups of patients, calcium stone formers (with or without metabolic alteration) and a control group, to detect possible differences. The findings of this study show that significant differences exist not only in the 24-hour average excretion between stone formers without alteration and healthy subjects but also in the mean concentration values between the stone former and control groups. The same results are obtained from the 2-hour urine analysis. It is concluded that 2-h urine analyses of GAGS have the same or more practical value than a 24-h urine analysis and that the results must be expressed in terms of concentration.

Calcium Oxalate↗

Inhibitory effect of pyrophosphate, citrate, magnesium and chondroitin sulphate in calcium oxalate urolithiasis.

The inhibitory capacity of pyrophosphate, citrate, magnesium and chondroitin sulphate was investigated, using the urine of 21 calcium oxalate stone-forming patients without metabolic alterations. The inhibitory effect of these substances was assessed by a combination of nephelometry (light scattering) and optical microscopy. The results showed that citrate and magnesium had an inhibitory effect in a significant number of cases. Pyrophosphate and chondroitin sulphate had a less marked effect. The main urinary lithogenic biochemical parameters of the patients were also studied to see if there was a relationship between them and the inhibitory capacity of the compounds.

Calcium Oxalate↗

Uric acid and its relationship with glycosaminoglycans in normal and stone-former subjects.

Uric acid is implicated in calcium oxalate kidney stone formation. Conspicuously so far, two hypotheses have been proposed: direct induction of calcium oxalate precipitation by uric acid, and uric acid as anti-inhibitor by binding urinary glycosaminoglycans (GAGS). The aim of this work is to evaluate uric acid and the relationship with GAGS in a group of patients with calcium oxalate lithiasis, and in a control group for detecting possible differences between the two groups. It was found that the lower concentration of GAGS in stone formers could impede their inhibitory activity on the heterogeneous nucleation of uric acid in calcium stone formation.

Biomarkers↗

Absorption and excretion in the experimental animal of a 14C-ethylmaleimide labelled peptide fraction of bovine factor VIII with antihaemorrhagic activity.

In this study the absorption and excretion of a peptide fraction from bovine Factor VIII (Vueffe) with antihaemorrhagic activity were investigated in rats and rabbits. The results obtained suggest that the peptide fraction may be absorbed from the gastrointestinal tract through an active transport or a process of nonselective pinocytosis. The radioactivity elimination was rapid and almost complete within 24 h. In addition no difference was observed between single or repeated dosing in the pharmacokinetic parameters. The evidence following routes of administration shows the good bioavailability of this peptide fraction of low molecular weight and confirms the efficacy after oral administration at very low doses.

Administration, Oral↗

[Introduction of an enzyme method for determining pyrophosphate in urine--a comparative study between patients with calculi and normal probands].

Interest aroused towards pyrophosphate as a possible inhibitor in calcium oxalate and phosphate lithiasis. A procedure for the quantitative determination of pyrophosphate in urine suitable for use in clinical laboratories is described. The reproducibility of the method was assessed by within-run and between-run reproducibility studies and the accuracy of the method was obtained by determining the amount of pyrophosphate recovered in urine samples. The present study compares the pyrophosphate excretion and concentration between a control group and a calcium oxalate stone former group.

Calcium Oxalate↗

Variations in the activity of urinary inhibitors in calcium oxalate urolithiasis.

Opinions vary on the effects produced by urinary inhibitors of crystallisation. We describe a simple method for studying inhibitory effects in urine based on nephelometry and optical microscopy. It was concluded that the inhibitory effect of a given substance on calcium oxalate crystallisation depends on the particular sample of urine being examined and that the most effective inhibitor can be determined only by studying the urine of each patient individually.

Calcium Oxalate↗

Simple method for the study of heterogeneous nucleation in calcium oxalate urolithiasis.

A simple method, based on optic microscopy and a counting chamber, has been devised for the study of heterogeneous nucleation in calcium oxalate urolithiasis. Calcium phosphate, uric acid, silica and macromolecular mucoprotein are proposed as possible nucleants. The importance of heterogeneous nucleation as a fundamental step in the formation of calcium oxalate calculi is demonstrated.

Calcium Oxalate↗

A possible role of the creatine phosphate-creatine pool in the regulation of the adenylate pool.

Human lymphoblastoid Raji cells and mouse hybridoma ascites cells incubated with 20 mM creatine showed significant increases in creatine, creatine phosphate and adenine nucleotide levels and in the energy charge. In human erythrocytes in which no variation of the creatine phosphate-creatine pool was observed because of a very low creatine kinase activity, the adenine nucleotide pool and the energy charge were not modified. These observations suggest not only a relationship among the creatine phosphate-creatine pool, the energy charge and the adenylate pool, but also the possibility to increase the energy charge and the adenylate pool in cells with creatine kinase activity by expanding the creatine phosphate-creatine pool.

Adenine Nucleotides↗

[Clinical significance of serum carnitine in the course and prognosis of dilated cardiomyopathy].

Serum carnitine is an essential cofactor for the transport of free fatty acids into the mitochondria. We determined the free and the total serum carnitine in 99 healthy blood donors and 58 patients with different forms of heart muscle disease. Thirty patients had dilated (DCM), 10 hypertrophic (HCM) and 8 alcoholic (ACM) cardiomyopathy and 10 patients had congestive heart failure of different etiology than cardiomyopathy (CHF). Free and total serum carnitine were determined by an enzymatic-spectrophotometric assay according to Pearson. Mean values for free and total serum carnitine were as follows: 47 and 74 mumol/l in controls (C; blood donors), 74 (P less than 0.01 vs. C) and 83 mumol/l in DCM, 66 (P less than 0.01 vs. C) and 89 mumol/l in HCM, 85 (P less than 0.01 vs. C) and 104 mumol/l (P less than 0.05 vs. C) in ACM and 86 (P less than 0.01 vs. C) and 129 mumol/l (P less than 0.01 vs. C) in CHF. Ten patients died during the mean observation time of 13 months, 8 patients with DCM and 2 with CHF; 9 of these 10 patients had initially a markedly increased serum carnitine. Patients with DCM were divided into two groups with normal (n = 15; 25-68 mumol/l) and increased (n = 15; greater than 68 mumol/l) free serum carnitine. Patients with increased serum carnitine showed a significantly higher mortality rate (47%) than patients with normal serum carnitine. It is concluded that free and total serum carnitine are elevated in patients with congestive heart failure, dilated and hypertrophic cardiomyopathy. The etiology of this carnitine metabolism disturbance is unclear but it is probably due to a secondary phenomenon in patients with congestive heart failure or primary myocardial hypertrophy. An increased serum carnitine is a poor prognostic sign in patients with dilated cardiomyopathy.

Adolescent↗