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L Felicetti

Publications and source records attributed to L Felicetti.

At least 37 records · Page 2Linked to original sources
PubMed1986

Molecular characterization of HbH disease in the Cuban population.

Molecular characterization of the alpha-thalassemia mutations present in nine HbH subjects from Cuba was achieved by digestion with Bam HI, Bgl II, and Apa I and hybridization with alpha- and zeta-specific probes. The results show that the molecular basis of the genetic defect is quite homogeneous, all the subjects carrying the - alpha 3.7 type I/--SEA genotype. Variations are observed in the size of the zeta polymorphic fragments.

Cuba↗
PubMed1986

Molecular basis for HbH disease in Italy: geographical distribution of deletional and nondeletional alpha-thalassemia haplotypes.

We have investigated the molecular basis for HbH disease in 16 patients from Sardinia, and central and southern Italy. We have shown that HbH disease is produced by the interaction of at least 10 different deletional or nondeletional alpha-thalassemia haplotypes, some of which have been already described in the Mediterranean area (--Med,-(alpha)20.5,-alpha 3.7 type I,-alpha 3.7 type II, alpha 2 NcoI alpha 1, alpha 2 HphI alpha 1). Among the new mutations found in the course of our study, there is a complete deletion of the zeta-alpha cluster and three nondeletional determinants (alpha alpha T), affecting to various extents alpha-globin gene expression. The different alpha-thalassemia haplotypes are not evenly distributed throughout the country. Two alpha 0 determinants [-(alpha)20.5 and the complete deletion of the zeta-alpha cluster] and four alpha + determinants (-alpha 3.7 type II, three nondeletional alpha alpha T mutations) are found exclusively in southern Italy.

Africa, Northern↗
PubMed1985

Frequency and types of deletional alpha+-thalassemia in northern Sardinia.

We determined by restriction mapping the frequency of the -alpha 3.7 determinant in a random sample of 48 adults in Northern Sardinia. We found a frequency of 0.18 +/- 0.04 and demonstrated that only type I crossover as determined by Apa I digestion (Higgs et al. 1984) is present. Moreover, we showed that this haplotype is not associated with an Rsa I polymorphism 5' to the alpha 2-globin gene. These data support the hypothesis of a unique origin of this deletion in Sardinia.

Adult↗
PubMed1985

Admission of Hb S heterozygotes to a general hospital is relatively reduced in malarial areas.

A comparison between the frequency of Hb S heterozygotes in blood donors, outpatients, and inpatients of a general hospital carried out at the Maputo Central Hospital, Mozambique, where Plasmodium falciparum malaria is endemic, showed a statistically significant lower percentage of Hb S heterozygotes in the inpatient group. Evidence is thus provided that the protection given by Hb S to heterozygotes concerns not only malarial infection itself, but probably a wide spectrum of diseases to which persons who have a special resistance to P falciparum infection are less prone.

Anemia, Sickle Cell↗
PubMed1984

The HbA/HbA2 ratio in newborns and its correlation with fetal maturity.

The relative amounts of HbF, HbA and HbA2 were determined in about 1000 newborns and their parents. In newborns the mean value of HbA2 was 0.27 +/- 0.02% and that of HbF 74.69 +/- 0.25%. The ratio HbA/HbA2 was estimated at different gestational ages and was found to range from 101 at 32 weeks gestation to 76 at 45 weeks, indicating that the relative amount of HbA2 increases with fetal maturation. The correlations between the levels of the different haemoglobins and various indexes of fetal maturation (gestational age, birth weight, crown-heel length and head circumference) are also given.

Adult↗
PubMed1978

Template activity for histones of poly(A)-minus RNA fraction from different developmental stages of Artemia salina embryos.

Template activity for histones of RNA fractions derived from Artemia salina embryos at different developmental stages were measured in a Krebs ascites cell-free system. Appreciable amounts of acid-soluble polypeptides comigrating with Hela cell histone markers on acrylamide gel electrophoresis were detected only when RNA fractions from nauplii were used. Tryptic peptide analysis by high voltage electrophoresis of the translational products had a pattern qualitatively similar to that of in vivo labeled histone markers from Hela.

Animals↗
PubMed1977

Actinomycin D inhibits hemoglobin synthesis in rabbit reticulocyte lysates and binds to a 15 S cytoplasmic particle involved in the initiation step of translation.

Actinomycin D inhibits hemoglobin synthesis in rabbit reticulocyte lysates by affecting initiation of globin polypeptide chains. To obtain information on the distribution of actinomycin-sensitive structures among the components of the translation machinery, a reticulocyte lysate is incubated with [3H]actinomycin. The tritium label is found associated with ribosomes actively engaged in protein synthesis and with a 15 S cytoplasmic particle. During cell-free incubation or when initiation is inhibited by aurintricarboxylic acid, the labeling of the 15 S particles increases, suggesting that they are relased from ribosomes into the cytoplasm and play a role in the initiation process. The 15 S cytoplasmic particles contain a DNAase-sensitive component, probably complexed with ribonucleic acids and proteins. A possible role of these DNA-containing particles in the initiation step of translation is discussed.

Aurintricarboxylic Acid↗
PubMed1975

Inhibition of hemoglobin synthesis by pancreatic deoxyribonuclease in rabbit reticulocyte lysates.

A pancreatic deoxyribonuclease preparation, shown to be free of significant ribonuclease activity, inhibits hemoglobin synthesis in a rabbit reticulocytelysate. Preincubation with DNAase (15 min at 25 degrees C) is required to obtain a marked inhibitory effect (nearly 70%). It has been shown that DNAase does not significantly interfere with the elongation or termination steps of translation, but it seems to prevent reinitiation of globin polypeptide chains allowing polysome run-off. In particular, the formation of the 40S/met-tRNAmetf complex is greatly reduced in the DNAase-treated lysate. At the moment the mechanism by which DNAase inhibits initiation is not clear.

Animals↗
PubMed1971

The mechanism of protein synthesis activation after fertilization of sea urchin eggs.

Upon fertilization of Paracentrotus lividus eggs, the ability of their ribosomes to form a ternary complex with poly(U) and phenylalanyl-tRNA is enhanced. In addition, it is possible to extract from ribosomes of the unfertilized egg a protein factor that inhibits polyphenylalanine synthesis by decreasing the binding of mRNA and aminoacyl-tRNA to the ribosomes. The observed increase in the rate of protein synthesis that occurs at fertilization could be accounted for by the removal of this inhibitory protein from the ribosomes.

Animals↗