Biomedical subjects

L Guidolin

Publications and source records attributed to L Guidolin.

9 recordsLinked to original sources

PubMed1999

Purification and characterization of a humoral opsonin, with specificity for D-galactose, in the colonial ascidian Botryllus schlosseri.

A humoral agglutinin from the hemolysate of the colonial ascidian Botryllus schlosseri was purified by affinity chromatography. This agglutinin does not require metal cations for its activity and is specific for derivatives of D-galactose. On SDS-PAGE analysis, it was resolved in two bands, of 17 and 19 kDa in reducing conditions and 15 and 16 kDa in non-reducing conditions. This behavior is due to the establishment of disulfide bridge between the thiols of cysteine, well represented in the molecule as revealed by amino acid analysis. The latter also indicated high percentages of hydrophilic residues, probably involved in sugar recognition. The lectin is an opsonin, as it increases both the phagocytic index and the number of phagocytized yeast cells. The hypothesis that this Botryllus agglutinin belongs to the galectin family of lectins is discussed.

Agglutinins↗

PubMed1999

Felbamate in refractory partial epilepsy.

This open-label study was performed to evaluate efficacy and safety of Felbamate (FBM) add-on therapy in drug-refractory partial epilepsy. We evaluated 36 patients (12 males) aged 11-68 years (mean 29.8) in which FBM was titrated gradually from 300 mg/day to a mean total maintenance daily dose of 1936 mg. Patients were monitored according to clinical practice and performed regularly laboratory tests. Mean follow-up of FBM therapy was 10 months (range 2-27). In this study, 5% of patients resulted to be seizure-free, 11% showed a seizure reduction more than 75%, 23% decreased their seizure frequency between 50% and 75% (P = 0.0001). The adverse events which were reported more frequently were: nausea, vomiting, anorexia and weight loss. Even if the patients sample is small FBM proves its efficacy in partial epilepsy, showing a relatively well tolerated profile.

Adolescent↗

PubMed1999

Intrauterine growth in the offspring of epileptic women: a prospective multicenter study.

The aim of the present study was to evaluate the risk of intrauterine growth delay in the offspring of epileptic mothers and to quantify the risks of intrauterine exposure to antiepileptic drugs (AEDs). Data concerning 870 newborns, prospectively collected in Canada, Japan and Italy, using the same study design, were pooled and analyzed. The overall proportion of newborns whose body weight (7.8%) or head circumference (11.1%) at birth were below the 10th percentile was not increased. However, logistic regression analysis showed that the risk of small head circumference was significantly higher in Italian than in Japanese (RR 4.2; 95% CI: 2.2-8.0) or Canadian children (RR 2.6; 95% CI: 1.1-6.5), and in children exposed to polytherapy (RR 2.7; 95% CI: 1.2-6.3), phenobarbital (PB) (RR 3.6; 95% CI: 1.4-9.4) and primidone (PRM) (RR 4.5; 95% CI: 1.5-13.8). Country was also the only factor affecting low body weight, with Italian children having a higher risk than Japanese (RR 5.2; 95% CI: 2.6-10.4) or Canadian (RR 8.8; 95% CI: 2.0-38.1) children. Due to the small categories, the influence of AED doses and plasma concentrations was studied for each individual AED, without adjustment for the other potential confounding factors. A clear dose-dependent effect was found for PB and PRM in terms of both small head circumference and low body weight, and a concentration-dependent effect for PB in terms of small head circumferences. The size of the difference between the Italian and the other two populations, which is only partially explained by differences in therapeutic regimens, suggests that genetic, environmental and ethnic factors also need to be taken into account when considering possible explanations.

Anticonvulsants↗

PubMed1999

Malformations in offspring of women with epilepsy: a prospective study.

PURPOSE: The incidence of malformations among infants of mothers with epilepsy treated with antiepileptic drugs (AEDs) during pregnancy is higher than that found in the general population. The aim of this study was to contribute to providing a definition of the rate of congenital anomalies in the offspring of mothers with epilepsy and to detect possible risk factors. METHODS: Since 1977, 517 pregnancies were followed up at the San Paolo Hospital in Milan by a team of epileptologists and obstetricians. The patients received monthly obstetric and neurologic examinations, and the blood levels of AEDs were tested monthly. During pregnancy the patients underwent ultrasound investigations to evaluate fetal morphology and development. At the time of delivery, the infants were submitted to a standardized examination by a pediatrician, and a more detailed clinical examination was performed on day 5. Malformations were classified as (a) genetic and chromosomic, (b) severe and mild malformations, and (c) deformities. RESULTS: The overall rate of malformations was 9.7%: of these, 5.3% were structurally severe, 2.2% were mild, 0.4% were chromosomic-genetic, and 1.8% were deformities. No malformation was detected in the 25 untreated patients. CONCLUSIONS: The risks of teratogenicity have been regarded as multifactorial, involving such factors as genetic predisposition, although most prospective studies show that AED-related factors are the primary risk factors for an increased incidence of congenital malformations.

Abnormalities, Drug-Induced↗

PubMed1998

Worsening in seizure frequency and severity in relation to folic acid administration.

We report a case of increase in seizure frequency and severity in a 26-year-old woman receiving folic acid at a dosage of 0.8 mg/day. She had symptomatic partial epilepsy with simple and complex seizures treated with carbamazepine. She was planning pregnancy and we prescribed folic acid for prevention of neural-tube defects. In the next few days she had a generalized tonic-clonic seizure for the first time and a significant increase in seizure frequency. Because of the temporal relation between the seizure worsening and the administration of folic acid, we hypothesize a role of folic acid in provoking seizures, as has been reported in the literature.Copyright Lippincott-Raven Publishers

Journal Article↗

PubMed1998

Chromosome 20 ring: a chromosomal disorder associated with a particular electroclinical pattern.

PURPOSE: The chromosome 20 ring [r(20)] is a rare chromosomal disorder without clear phenotypical markers. We describe the electroclinical pattern in a group of patients with r(20). METHODS: We observed 3 patients (a boy, patient 1; his mother, patient 2; and an unrelated man, patient 3), performing prolonged video-EEG and cytogenetic studies and fluorescent in situ hybridization (FISH) with chromosome-specific telomeric probes. RESULTS: All 3 patients had a very similar abnormal electroclinical pattern characterized by long bursts or trains of rhythmic theta waves, which were sharply contoured or had a notched appearance (with no detectable clinical correlate), and generalized spike waves (SW) associated with seizures of probable frontotemporal origin (SFT). In all 3 patients, the cytogenetic analysis of T lymphocytes showed mosaicism with a normal cell line and a second cell line with a chromosome 20, although the latter was little represented in patients 2 and 3. A few cells with a single chromosome 20 were also found. The same cytogenetic findings were confirmed in the lymphoblastoid cell line of patient 1 and in the fibroblasts of patient 3. FISH with chromosome-specific telomeric probes and TTAGGG sequences demonstrated the integrity of the ring chromosomes. CONCLUSIONS: The clinical picture of these patients appears to be related to the instability of the r(20)-generating cells monosomic for chromosome 20 and is thus haploinsufficient for a gene. In these patients, the electroclinical pattern of theta waves (probably unrelated to epilepsy) and the SW and SFT, even with mild mental retardation (MR) or no MR and without dysmorphic features, suggest that the r(20) syndrome may be present.

Adolescent↗

PubMed1987

Biochemical and ultrastructural data on Tetrahymena pyriformis treated with copper and cadmium.

The addition of copper (10 micrograms ml-1) or cadmium (5 micrograms ml-1) to the medium is well tolerated by Tetrahymena pyriformis GL. Both metals are accumulated by cells, cadmium to a greater extent than copper. The growth rate is not affected and from the micrographs it is evident that the ultrastructure is not altered by the treatments. After 3 days of culture the macronucleus contains dense masses of chromatin and numerous nucleolar fusion bodies. Granules, cytolysomes and many food vacuoles are present in both control and treated cells. Cadmium induces the formation of a chelating protein; the amino acid analyses and the ultraviolet spectrum indicate that it is similar to the metallothionein isolated by higher organisms. The molecular weight of native protein is about 27,000. After treatment by sulphitolysis or oxidation we obtained a peak of molecular weight at about 6,000. The treatment with copper does not appear to induce metallothioneins or other chelatins. The high tolerance of Tetrahymena towards cadmium is believed to be due to the formation of a Cd-Zn metallothionein. The different chelating proteins induced by copper and cadmium in other groups of Protozoa and the different detoxification mechanisms present in these organisms are discussed.

Amino Acid Sequence↗

PubMed1985

Chelatins in Euglena gracilis and Ochromonas danica.

Amino acid analysis was performed on low molecular weight copper binding proteins purified from two species of Protozoa after exposure to a high level of this metal. The compound from Ochromonas is similar to Cu-chelatins. The two peptides from Euglena have a different molecular weight and a very dissimilar amino acid composition. Peptide No. 1 has a peculiar composition with a high content of aspartic acid and arginine. Some speculations are made about its detoxification role in comparison with other compounds found in blue-green algae.

Amino Acid Sequence↗

PubMed1984

Globin evolution in some species of the genus Bufo.

The globins of 10 species of toads of the genus Bufo have been analysed. From the values of the reciprocal rates between their amino acid residues a 'dissimilarity matrix' was made. In this have been included the values related to Discoglossus pictus and Xenopus laevis. The numerical data, derived from a computer program, gave a dendrogram representing the evolution of the analysed globins. This appears correlated to the geographical distribution and to the metabolic adaptation of the corresponding species of Bufo more than their chronological appearance.

Amino Acids↗