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R Scacchi

Publications and source records attributed to R Scacchi.

47 records · Page 3Linked to original sources

Genetic polymorphisms in juvenile-onset diabetes.

Nine genetic polymorphic systems (ACP1, PGM1, ADA, AK, G-6-PD, Hp, ABO, Rh, MN), were studied in a series of 138 subjects affected by JOD. Differences between diabetic patients and controls were observed in the distribution of phenotypes of the red cell acid phosphatase (ACP1), and the ABO and MN blood groups.

Acid Phosphatase↗

A study of nine polymorphic systems in the population of the Po Delta.

The present work reports a study of nine genetic polymorphic systems in the area of the Po Delta where malaria was endemic since the XIV century. Our data confirm some characteristics of this population already reported by other authors such as the high prevalence of thalassemia, the low prevalence of the rh (d) gene and the presence of G-6-PD deficiency. Among the other systems studied, i.e., AP, PGM1 ADA and AK, only AP frequencies of Po Delta population are significantly different from those of other continental Italian populations, the PC allele showing the lowest frequency so far observed.

Acid Phosphatase↗

Genetic differentiation among Sardinian villages.

The present study reports an analysis of genetic differentiation among 14 Sardinian villages located mainly in the center of the island. Chi-square tests show significant genetic heterogeneity among villages, and analyses by F- and R- statistics indicate an essentially random pattern of differentiation for all alleles. Using the kinship methods of Morton, a matrix, R, with elements rij describing the correlations between the gene frequencies of villages i and j is obtained. Use of Malécot's formula relating the rij to the geographic distances between villages shows a rapid decline of kinship with increasing distance but reveals essentially no relationship for distances over 40 km. Rotation of a two-dimensional reduction of the kinship matrix to maximum congruence with the geographic distances indicates that about 25% of the genetic distances can be accounted for by the geographic location of the villages. Isolation due in part to cultural factors, genetic drift, and special local or regional patterns of villages associations appear to be involved in the pattern of genetic variation.

Adolescent↗

Plasma alpha1-antichymotrypsin in Alzheimer's disease; relationships with APOE genotypes.

Inflammatory processes are thought to be important contributors to the pathogenesis of Alzheimer's disease (AD). alpha1-antichymotrypsin (ACT) is a proteinase inhibitor characteristic of acute-phase inflammation and has been identified in amyloid plaques. We analyzed the plasma ACT levels in a sample of subjects with late-onset AD and correspondent controls. Plasma ACT was higher in AD patients (62.8 +/- 20.2 mg/dl) than in controls (58.8 +/- 18.1 mg/dl), but not significantly (P = 0.13). In the AD patients regression analysis showed a positive linear relationship between ACT levels and duration of the disease (P = 0.037). Increased ACT concentrations (64.6 +/- 21.2 mg/dl) were also found in patients with greater cognitive impairment (MMSE scores < 20), but since this factor depends on the duration of the disease as well, our present data seem to indicate a complex relationship involving elevated ACT levels, disease duration and cognitive impairment. Plasma ACT was found to differ significantly according to APOE genotypes (P = 0.017), the highest levels being associated to E3-E3 homozygotes (66.1 +/- 17.8 mg/dl) and the lowest to E4-E3 subjects (53.1 +/- 18.2 mg/dl). In patients not carrying APOE*4 allele the ACT levels were higher than in controls (P = 0.014), and the relationship between ACT and disease duration was stronger than that observed in the total AD sample (P = 0.003), but it was absent in those carrying APOE*4 (P = 0.67). Taken together our results seem to suggest that inflammation is a relevant factor in AD pathogenesis for subjects with E3-E3 and E3-E2 genotypes but less important for APOE*4 carrying subjects.

Aged↗

Screening of two mutations at exon 3 of the apolipoprotein E gene (sites 28 and 42) in a sample of patients with sporadic late-onset Alzheimer's disease.

The search for further variation at the APOE gene in a sample of patients with sporadic late-onset Alzheimer's disease (AD) and related controls revealed two different mutations in the exon 3 of the gene. One, the Leu28-->Pro, always found on an APOE e(*)4 allele, was present in five of the 94 patients and in 1 of the 157 controls. The other, Thr42-->Ala, found on an e(*)3 allele, was observed in only one AD patient, who also carried the Leu28-->Pro, but in none of the controls. In the AD patient group the allele e(*)4(-), corresponding to Leu28-->Pro, showed a frequency of 0.027, compared with only 0.003 in the controls. Compared to E3/3 and E3/2 genotypes, the risk of developing AD associated with the genotypes carrying the e(*)4 allele, the well-established risk allele for AD onset, was observed to be high (OR=3.16; 95% CI=1.62-6.20; P=0.0009), but the risk associated with genotypes carrying the Leu28-->Pro mutation was higher still (OR=10.95; 95% CI=1.25-95.75; P=0.015). The higher risk associated with this mutation was assessed by meta-analysis carried out using the data of three patient groups from a previously published study Kamboh et al. and from our study. The results indicated that, compared with all the other APOE genotypes, those carrying the Leu28-->Pro mutation were at a substantially higher risk of developing AD (OR=4.25; 95% CI=1.21-14.97).

Age of Onset↗

The Cayapa Indians of Ecuador: a population study of seven protein genetic polymorphisms.

The Cayapa Indians are a population of 3600 individuals living in Ecuador, along the Cayapas River and its tributaries. They are thought to have migrated from the Andes, north of Quito, and settled in the Cayapas area five centuries ago as a consequence of Inca expansion and of the Spanish conquest. In order to study the genetic structure of the Cayapa and their relationships with other native American peoples, and to enquire on the possibility of admixture from nearby Black communities, we have investigated a sample of 139 individuals for seven plasma genetic markers (F13A, F13B, ORM1, AHSG, C6, C7 and APOC2) by isoelectric focusing and immunoblotting. The following gene frequencies have been found: F13A*1 = 0.824, F13A*2 = 0.176; F13B*1 = 0.126, F13B*3 = 0.874; ORM1*1 = 0.554, ORM1*2 = 0.446; AHSG*1 = 0.275, AHSG*2 = 0.725; C6*A = 0.131, C6*B = 0.814, C6*A21 = 0.055; C7*1 = 1.000; APOC2*1 = 1.000. The findings confirm, whenever the comparison was possible, quite a good resemblance of the Cayapa with other Native American populations.

Alleles↗

DNA polymorphisms of apolipoprotein B and angiotensin I-converting enzyme genes and relationships with lipid levels in Italian patients with vascular dementia or Alzheimer's disease.

The distribution of three DNA polymorphisms (XbaI, EcoRI, and I/D) of the apolipoprotein B (APOB) gene, and of the I/D polymorphism of the angiotensin I-converting enzyme (ACE) gene was investigated in 53 patients with vascular dementia, in 80 patients with late-onset sporadic Alzheimer's disease, and in 153 age-matched control subjects. Furthermore, plasma total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides were measured in the three groups and the involvement of the genetic variation at APOB locus on lipid levels was determined. Major findings of this work are (1) no genotype or allele of the polymorphisms examined here seemed to be associated with vascular dementia or with Alzheimer's disease, (2) total cholesterol and LDL cholesterol levels were lower in Alzheimer's disease patients than in vascular dementia patients and in elderly controls, and (3) the dementia patients with APOB EcoRI R+R- genotype had higher total cholesterol and LDL cholesterol levels than R+R+ homozygotes.

Aged↗

Polymorphisms of the apolipoprotein E gene regulatory region and of the LDL receptor gene in late-onset Alzheimer's disease in relation to the plasma lipidic pattern.

Two new polymorphisms in the regulatory region of the apolipoprotein E gene, -491 A/T and -427 T/C, have been reported to be associated with the risk of Alzheimer's disease (AD). Moreover, in vitro studies suggest that the two polymorphisms modulate the levels of apoE protein expression. We examined these two polymorphisms, as well as the MspI polymorphism in the LDL receptor gene, in a series of elderly patients with late-onset sporadic AD and in an age-matched control group but failed to find any kind of association between these genetic features and an increased risk of AD. In the same samples we investigated the relationships between various genotypes and plasma lipid levels. Since the well-known effect of the three-allelic APOE polymorphism on plasma lipid levels could mask the effect of other polymorphisms, the analyses were performed taking into account the APOE genotype. The two regulatory region polymorphisms had significant effects only on the apoE levels. The -427 TT homozygotes had lower, and the -491 AA homozygotes had higher levels of apoE than other genotypes. This result confirmed in vivo the already observed in vitro effects of -491 A/T and -427 T/C polymorphisms on APOE promoter transcription activity.

Age of Onset↗