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Biomedical subjects

S Bertolini

Publications and source records attributed to S Bertolini.

At least 19 recordsLinked to original sources
PubMed1992

RFLPs of the LDL-receptor gene: their use in the diagnosis of FH and in evaluation of different levels of gene expression on normal subjects.

The usefulness of the RFLPs of the LDL-receptor gene in early diagnosis of Familial Hypercholesterolemia (FH) was investigated in 122 FH-families. Four RFLPs, produced by digestion with the enzymes PvuII, ApaLI and AvaII/XbaI were able to detect the affected gene and to follow the inheritance of the disease in 72 out of 97 families (74%). In the remaining 25 families, unambiguous diagnosis was possible in 66% of the cases by use of PvuII, ApaLI and BstEII/EcoRI RFLPs. The RFLPs were also useful to distinguish true homozygotes from compound heterozygotes and to detect families where recombination events occurred or where hypercholesterolemia was not due to a defect of the LDL-receptor gene. In a normal population PvuII RFLP account for 9.6% of the total variance of the LDL cholesterol levels adjusted for confounding variables. The P2 allele was associated with lower LDL cholesterol concentrations (average excess -9.1 mg/dl). This finding allows us to presume there is a DNA sequence, close to the variable PvuII cutting site in intron 15, which could act as an enhancer of the LDL-receptor gene expression.

Adult↗
PubMed1992

[Epidemiologic study on the effectiveness and safety of dihydroergocristine in impaired memory and behavioral functions in aged humans].

Aim of the study was to assess the activity of dihydroergocristine (DHEC, CAS 17479-19-5) in aged patients with impaired cognitive function. Twenty-five university hospital centres and 250 physicians participated in the study. 2,600 patients (1,104 males and 1,496 females, age range 50-80 years) were admitted to the study. Each patient was administered 6 mg/d DHEC for 120 days. Clinical evaluation was made through the SCAG Rating Scale registered at basal time, after 60 and 120 days. Responsivity to treatment was considered high when the final score was reduced by 30% and none if less than 10%. Analysis of results demonstrated that at the end of the study responsivity was high in 73% of cases, moderate in 20.4% and absent in 6.5%. Tolerability was very good as side effects were reported only in 3.16% of patients. Most frequent side effects were: nausea (1.23%), gastralgia (1.11%), headache (0.29%), hypotension (0.12%), vertigo (0.12%) and rash (0.08%). Drop-outs for gastralgia were reported only in 0.53% of the patients.

Aged↗
PubMed1992

A large deletion in the LDL receptor gene--the cause of familial hypercholesterolemia in three Italian families: a study that dates back to the 17th century (FH-Pavia).

In the LDL-receptor gene, a large rearrangement causing hypercholesterolemia was detected in three apparently unrelated families living in northern Italy. In all probands, binding, internalization, and degradation of 125I-LDL measured in skin fibroblasts were found to be 40%-50% of control values, indicative of heterozygous familial hypercholesterolemia (FH). Southern blot analysis revealed that the probands were heterozygous for a large (25-kb) deletion of the LDL-receptor gene eliminating exons 2-12. The affected subjects possessed two LDL-receptor mRNA species: one of normal size (5.3 kb) and one of smaller size (3.5 kb). In the latter mRNA, the coding sequence of exon 1 is joined to the coding sequence of exon 13, causing a change in the reading frame and thereby giving rise to a premature stop codon. The receptor protein deduced from the sequence of the defective mRNA is a short polypeptide of 29 amino acids, devoid of any function. Tracing these three families back to the 17th century, we found both their common ancestor and the possible origin of the mutation, in a region which is called "Lomellina" and which is located in southwest Lombardy, near the old city of Pavia. Therefore we named the mutation "FH-Pavia."

Adolescent↗
PubMed1991

Duplication of exons 13, 14 and 15 of the LDL-receptor gene in a patient with heterozygous familial hypercholesterolemia.

During a survey of Italian patients with familial hypercholesterolemia (FH), we identified an FH heterozygous patient with a gross rearrangement of the low density lipoprotein (LDL) receptor gene. Southern blot analysis of the proband's DNA digested with restriction enzymes PvuII, BamHI, BglII and XbaI and hybridization with cDNA probes complementary to the 3' end of the gene revealed the presence of abnormal fragments that were approximately 7 kb larger than their normal counterparts. DNA digestion with other enzymes (EcoRV, NcoI, KpnI and StuI) and hybridization with probes complementary to exons 13-17 generated normal fragments and an abnormal fragment of 6.3-6.8 kb. These results are consistent with the presence of an insertion of approximately 7 kb caused by a duplication of exons 13, 14 and 15. This is a novel mutation that is most probably the result of an unequal crossing-over between repetitive sequences located in intron 12 and intron 15. This novel mutation has been designated FHBologna 2.

Aged↗
PubMed1990

Use of three DNA polymorphisms of the LDL receptor gene in the diagnosis of familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is an autosomal dominant metabolic disorder caused by several different mutations in the low density lipoprotein (LDL) receptor gene. This large number of different mutations, often undetectable in Southern blotting, makes it impossible directly to diagnose the disease. However, restriction fragment length polymorphisms (RFLPs) can be used to follow the inheritance of the defective gene in FH families. In the present study, we report the use of three RFLPs, detected by PvuII, ApaLI and AvaII restriction enzymes, to determine the haplotypes of normal and defective LDL receptor genes in 61 families with FH and in 128 normal individuals. Two of the nine haplotypes were significantly more often associated with the affected genes, whereas one was significantly less frequent. Although none of the associations was strong enough to allow diagnosis in individuals, it was possible, using the three RFLPs, to identify the haplotype of the affected gene in 57 families and to carry out unequivocal diagnosis in 67% of the cases. In four families, PvuII and AvaII detected an abnormal fragment co-segregating with the disease, thus increasing the percentage of diagnosis to 73.4% of the cases.

Alleles↗
PubMed1989

Endocrine, metabolic, and clinical effects of gestrinone in women with endometriosis.

The effect of oral gestrinone, 2.5 mg twice weekly for 6 months, was studied in 11 women with mild or moderate endometriosis laparoscopically confirmed. The mean laparoscopic score decreased from 17.18 to 9.09 (P greater than 0.005). Painful symptoms were relieved in all patients within 2 months from start of therapy. Gonadotropins, prolactin (PRL) 17 beta-estradiol (17 beta-E2), estrone (E1), progesterone (P), androstenedione (A), and dehydroepiandrosterone sulfate (DHEA-S) remained in the follicular phase range. Total testosterone (TT) and sex hormone-binding globulin (SHBG) decreased, whereas free testosterone (FT) slightly increased. Metabolic studies showed a decrease of total triglycerides, very low-density lipoprotein (VLDL) triglycerides, and high-density lipoprotein (HDL) and VLDL cholesterol, parallel to the decrease of associated apoproteins. Low-density lipoprotein cholesterol and apoprotein B increased during therapy. The results suggest that gestrinone possesses antiestrogenic, androgenic, and progestigenic effects at therapeutic dosages both by acting on central and peripheral steroid receptors. For its efficacy and good tolerance, gestrinone may be considered an option for treating endometriosis.

Adult↗
PubMed1988

Direct modulation of insulin receptor protein tyrosine kinase by vanadate and anti-insulin receptor monoclonal antibodies.

Sodium vanadate activates "in vitro" insulin receptor autophosphorylation and protein tyrosine kinase in a dose-dependent manner. Insulin receptor protein tyrosine kinase is directly activated also by the anti-insulin receptor beta subunit monoclonal antibody 18-44. We previously demonstrated that the anti-insulin receptor monoclonal antibody MA-10 decreases insulin-stimulated receptor protein tyrosine kinase activity "in vitro", without inhibiting insulin receptor binding. In this report we show that insulin receptor protein tyrosine kinase, activated by sodium vanadate or by monoclonal antibody 18-44, is inhibited by MA-10 antibody. These data suggest that insulin receptor protein tyrosine kinase activity can be either activated and inhibited through mechanisms different from insulin binding.

Animals↗
PubMed1988

Effect of a single daily dose treatment of fenofibrate on plasma lipoproteins in hyperlipoproteinaemia IIb.

The safety and efficacy of a single daily dose of fenofibrate (200 mg) have been evaluated in 12 Type IIB hyperlipidaemic patients in a three-month study. At the same time the pharmacokinetics was studied to check whether this new dosage schedule would give a therapeutic plasma levels of fenofibrate. At the single daily dose of 200 mg, fenofibrate was highly effective, very well tolerated, and it reached therapeutic plasma levels without accumulation. It appears that fenofibrate can usefully be employed at this dosage in hyperlipidaemia, especially since patient compliance is better when only one daily dose need be taken.

Adult↗
PubMed1988

Adjuvant tamoxifen in primary breast cancer: influence on plasma lipids and antithrombin III levels.

The possible estrogenic effects of tamoxifen on plasma lipids and antithrombin III levels were investigated in 91 breast cancer patients. Mean values of total, HDL and LDL cholesterol, triglycerides, glucose, uric acid, and antithrombin III were evaluated in 55 patients on adjuvant tamoxifen for at least 3 months and compared with those found in 36 patients on no therapy. Total cholesterol, LDL cholesterol, and antithrombin III levels were significantly lower in treated patients (p less than 0.05). Our results support the hypothesis of a partial agonist action of this antiestrogen, although general clinical practice suggests that tamoxifen-related thrombotic events are rare.

Antithrombin III↗
PubMed1987

Effects of three low-dose oral contraceptive formulations on lipid metabolism.

Three oral contraceptive preparations were studied in 60 healthy women. This randomized, comparative, baseline controlled study was designed to investigate the effects of the preparations on plasma lipids and lipoproteins. The following formulations were studied: a monophasic preparation containing ethinylestradiol and desogestrel (M-DSG) and two triphasic formulations containing ethinylestradiol and gestodene or levonorgestrel respectively (T-GSD and T-LNG). These preparations were studied for six treatment cycles. Total cholesterol and apoprotein B did not change in any group. Low density lipoprotein (LDL) cholesterol was significantly decreased in the groups of women treated with M-DSG and T-GSD respectively. No changes were observed in the T-LNG group. With M-DSG, significant increases were observed in high-density lipoprotein (HDL) cholesterol and HDL3 cholesterol, whilst HDL2 cholesterol did not change. With both T-GSD and T-LNG, no changes were observed in HDL cholesterol, whilst a significant increase in HDL3 cholesterol together with a trend to decrease in HDL2 cholesterol were observed. Apolipoprotein AI increased with the following ranking M-DSG greater than T-GSD greater than T-LNG. The LDL/HDL cholesterol ratio significantly decreased with both M-DSG and T-GSD. In the T-LNG group there was no change in this ratio. Triglycerides increased to the same extent in all treatment groups. As far as concerns the risk of arterial diseases, these three oral contraceptive formulations mostly induced negligible and/or partly favorable changes in plasma lipids and lipoproteins; however, the lipoprotein pattern during M-DSG treatment resulted better than during T-GSD, and the latter turned out to be better than during T-LNG.

Adolescent↗
PubMed1986

Lipoprotein changes induced by pantethine in hyperlipoproteinemic patients: adults and children.

Following a brief outline of current knowledge concerning atherosclerosis and its treatment, the authors describe the results obtained by treating with pantethine (900-1200 mg daily for 3 to 6 months) a series of 7 children and 65 adults suffering from hypercholesterolemia alone or associated with hypertriglyceridemia (types IIa and IIb of Fredrickson's classification). Pantethine treatment produced significant reduction of the better known risk factors (total cholesterol, LDL-cholesterol, triglycerides, and apo-B) and a significant increase of HDL-cholesterol (signally HDL2) and apolipoprotein A-I. The authors conclude with a discussion of these results and of the possible role of pantethine in the treatment of hyperlipoproteinemia, in view of its perfect tolerability and demonstrated therapeutic effectiveness.

Adolescent↗
PubMed1985

Insulin receptor binding on red cells of hypertriglyceridemic patients. Effect of a low fat, low carbohydrate diet.

Insulin binding on circulating red cells has been studied in hypertriglyceridemic (HTG) patients before and after normalization of plasma TG levels by a low fat and low CHO diet, followed for 2 months. Under basal condition HTG patients showed lower insulin binding on red cells (B/T) than control subjects. The reduction in binding was due to a lower receptor number (binding capacity). After the diet and normalization of TG levels, insulin binding was identical in HTG patients and always lower than in controls. The fasting values of blood glucose, IRI, FFA, were also unchanged after TG reduction, suggesting, together with the low insulin binding, a state of insulin resistance. We conclude that our lean patients, affected by HTG, present a state of insulin resistance. Despite normalization of plasma TG, obtained with diet alone, insulin receptor binding on red cells in unchanged.

Cholesterol↗
PubMed1984

Effects of physical activity and diet on lipemic risk factors for atherosclerosis in women.

Serum lipoproteins were studied in active and sedentary young women. The groups were matched for age, body weight, and blood pressure. A quantitative and qualitative evaluation of the diet was performed. In spite of a higher intake of saturated fat and cholesterol, serum concentrations of triglyceride, total cholesterol, and low-density lipoprotein cholesterol in the active group were not significantly different from the controls. Nevertheless, high-density lipoprotein cholesterol (HDL-C) levels were significantly higher in the active subjects even after covariance adjustment for nutrient intake; therefore, the HDL-C increase seems to depend on physical activity "per se" rather than on differences in diet.

Adult↗
PubMed1982

[Evaluation of the accuracy of precipitation methods for HDL cholesterol determination].

Several methods for HDL-Cholesterol determination have been proposed; the over-floating cholesterol evaluation after non-HDL lipoproteins precipitation by polyanions with bivalent cations or neutral polymers is practical and not expensive, but it's accuracy and precision must be strictly control led. The Authors, after a review and a quality-check of the most used methods, conclude that the best accuracy for HDL-Cholesterol determination is provided by Dextransulphate-Mg-chloride and Phosphotungstate-Mg-chloride at pH 7,5.

Chemical Phenomena↗