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Biomedical subjects

F Pelliccia

Publications and source records attributed to F Pelliccia.

70 records · Page 4Linked to original sources
PubMed1984

Analysis of the DNA replication pattern of a translocation (tX/X, qter----p221::p223----qter) chromosome in leukocyte and fibroblast cultures.

The results of a detailed analysis of DNA replication in a late replicating tX/X chromosome (qter----p221::p223----qter) are reported. The chronology of DNA replication has been analyzed by comparing (a) the replication patterns of each of the two moieties of the translocation chromosome in different cells and (b) the two moieties with each other in the same cell. The study has been done on leukocyte and fibroblast cultures after BUdR incorporation. A comparison with the late replication pattern of the normal X chromosome has also been done.

Cells, Cultured↗
PubMed1983

Silver positivity of the NORs during embryonic development of Xenopus laevis.

Transcriptional activity of ribosomal RNA (rRNA) genes is detectable around blastula-gastrula transition during the embryonic development of amphibians and other non-mammalian systems. The silver staining reaction, known to selectively stain transcriptionally active nucleolus organizer regions (NORs) both in interphase and metaphase chromosomes allowed us to follow the activation of the NORs during the embryonic development of Xenopus laevis.

Animals↗
PubMed1983

Screening for cytogenetic polymorphisms in a random sample of liveborn infants from Italian population.

The frequency of major and minor chromosome variants is studied in a random sample of newborns in Central Italy. Special attention is paid to the objective criteria used to evaluate minor variants. In our sample, the frequency of acrocentric chromosome variants is found to be unusually high compared with previous studies. Also, the distribution of C-band sizes differs from that reported for other populations, while the frequency of major chromosome variants is found to be the same.

Chromosome Banding↗
PubMed1982

Silver staining of the nucleolus organizer regions (NOR) requires clusters of sulfhydryl groups.

Silver stainability of nucleolus organizer regions (NORs) appears to be correlated with the presence of grouped sulfhydryl (SH) side chains of proteins. In fact, heavy metals with high affinity for SH groups, such as Hg and Cu, do prevent the silver staining reaction. Ferricyanide, which is known to oxidize SH to disulfides, also prevents any further reaction with silver. On the other hand, alkali and reducing agents (mercaptoethanol, cyanide) do not affect silver stainability of the NORs. These results show that the silver staining reaction is not related to disulfide or persulfide groups and that alkali-soluble, acidic nuclear proteins per se do not play a major role in this process.

Cell Nucleolus↗
PubMed1981

Clonal inheritance of rRNA gene activity: cytological evidence in human cells.

Clone-specific silver staining patterns of the nucleolus organizers (NOs) were observed in clones deriving from a human diploid fibroblast culture. Each specific staining pattern corresponds to one of the nine patterns observed in the general population. Since silver stainability of the NOs is related to rRNA gene function, these data demonstrate the clonal inheritance of rRNA gene activity.

Cells, Cultured↗
PubMed1980

Cytogenetic and clinical studies in gonadal dysgenesis with 46,X,Xt(qter leads to p221::p223 leads to qter) karyotype: review and phenotype/karyotype correlations.

Chromosome analysis by Q, R, and C banding was performed in a case diagnosed clinically as gonadal dysgenesis and the karyotype was shown to be 46,X,Xt(qter leads to p221::p223 leads to qter). Localisation of the breakpoints in the fused X chromosomes and replication studies have led to a hypothesis on the origin of the translocation. A comparison of clinical and cytogenetical findings in this and other published cases has also been made in an attempt to detect some phenotype/karyotype correlations.

Adult↗
PubMed1978

Ag staining of the nucleolus organizer (NO) and its relationship to satellite association.

The frequency of involvement in satellite association and the frequency of selective staining of the secondary constrictions with silver solutions have been studied in five phenotypically normal individuals, all carriers of morphological variants of the nucleolus organizing region (NOR). The results show the preferential involvement of some morphological markers in satellite association, and also their preferential staining with Ag-I. It has also been shown that acrocentric chromosomes involved in satellite association are always stained by silver.

Cell Nucleolus↗
PubMed1977

Nucleolus organizer and N-band distribution in morphologic and fluorescence variants of human chromosomes.

Three cases of morphologic variants of human D- or G-group chromosomes have been studied by N- and Ag-AS banding techniques. The results confirm our previous findings about the localization of nucleolus organizers on the secondary constrictions of acrocentric chromosomes. Preliminary results on the distribution and number of N bands in D- and G-group chromosomes with morphologic and fluorescence variants are reported.

Cell Nucleolus↗
PubMed1977

A new translocation involving chromosomes no. 5 and no. 12 t(5;12) (5q15;12p13).

A new case of translocation between chromosomes No. 5 and No. 12 is described. The translocation t(5;12) (5q15;12p13) is apparently balanced and was found in a child aged 3 1/2 years who was affected with severe psychomotor retardation. On the basis of the clinical picture it is suggested that the phenotype could be not dependent on the chromosomal alteration.

Child, Preschool↗
PubMed1976

Nucleolus organizer and satellite association in a variant D-group chromosome.

A No. 15 chromosome with a short arm longer than usual is observed in two phenotypically normal brothers. This chromosome appears to have no visible satellite, shows no N-band staining, and is never involved in satellite association. These results have led us to the conclusion that this chromosome lacks the nucleolus organizer region.

Cell Nucleolus↗
PubMedDate not supplied

Inter- and intra-chromosomal distribution of chromatid breaks induced by X-rays during G2 in human lymphocytes.

Cultures of blood from healthy adults were irradiated 48 h after stimulation with 240 R of X-rays and fixed after various time intervals (0-2 h, 2-4 h, 4-6 h). 3HTdR was added to several cultures after irradiation. Mitotic and labelling indices were used to distinguish between two cell samples inside the irradiated G2 population: D- cells reaching mitosis without mitotic delay and a high frequency of chromatic breaks and D+ cells with mitotic delay and which, during the delay, repair most of the damage produced. After R banding 450 chromatid deletions were located in each of the two cell samples. The D+ cells showed a higher frequency of breaks than the D- cells with decreasing chromosome size, in the telomeric and centromeric region and in the junction between the R+ and R- bands. These results can be interpreted as indicative of a non-random distribution of repair processes both between and within chromosomes.

Chromosome Aberrations↗