Carlo Torre

Role of L-Selectin in the Vascular Homing of Peripheral Blood-Derived Endothelial Progenitor Cells

Ex vivo expanded endothelial progenitor cells (EPCs) represent a new potential approach for the revascularization of ischemic sites. However, local accumulation of infused EPCs in these sites is poor, and the mechanisms responsible for their homing are largely unknown. We observed the expression of L-selectin, an adhesion receptor that regulates lymphocyte homing and leukocyte rolling and migration, on ex vivo expanded blood-derived human EPCs. When EPCs were subcloned in SV40-T large Ag-transfected isolates, the copresence of L-selectin and endothelial lineage markers was confirmed. We therefore demonstrated that the expression of L-selectin by EPCs was functional because it mediates interaction with a murine endothelial cell line (H.end) expressing L-selectin ligands by way of transfection with α(1,3/4)-fucosyltransferase. Indeed, adhesion of EPCs after incubation at 4°C on a rotating platform was enhanced on α(1,3/4)-fucosyltransferase-transfected H.end cells compared with control vector-transfected cells, and treatment with anti-L-selectin Abs prevented this event. We then studied the role of L-selectin in EPC homing in vivo. H.end cells were implanted s.c. in SCID mice to form endothelioma tumors, and EPCs were subsequently i.v. injected. L-selectin+ EPCs localized into α(1,3/4)-fucosyltransferase-transfected endothelial tumors to a greater extent than in control tumors, and they were able to directly contribute to tumor vascularization by forming L-selectin+ EPC-containing vessels. In conclusion, our results showed that a mechanism typical of leukocyte adhesion is involved in the vascular homing of EPCs within sites of selectin ligand expression. This observation may provide knowledge about the substrate to design strategies to improve EPC localization in damaged tissues.

Analysis of Y-chromosomal SNP haplogroups and STR haplotypes in an Algerian population sample.

The distribution of Y-chromosomal single nucleotide polymorphism (SNP) haplogroups and short tandem repeat (STR) haplotypes was determined in a sample of 102 unrelated men of Arab origin from northwestern Algeria (Oran area). A total of nine different haplogroups were identified by a panel of 22 binary markers. The most common haplogroups observed in the Algerian population were E3b2 (45.1%) and J1 (22.5%). Y-STR typing by a 17-loci multiplex system allowed 93 haplotypes to be defined (88 were unique). Striking differences in the allele distribution and gene diversity of Y-STR markers between haplogroups could be found. In particular, intermediate alleles at locus DYS458 specifically characterized the haplotypes of individuals carrying haplogroup J1. All the intermediate alleles shared a common repeat sequence structure, supporting the hypothesis that the variant originated from a single mutational event.

Development of two multiplex PCR systems for the analysis of 12 X-chromosomal STR loci in a northwestern Italian population sample

Two multiplex polymerase chain reaction systems for the automated profiling of 12 X-chromosomal short tandem repeat (STR) markers were developed. Multiplex A consisted of DXS6789, DXS6809, GATA172D05, DXS101, DXS8378, and DXS8377. Multiplex B consisted of DXS7132, DXS6800, DXS6801, DXS7424, HPRTB, and DXS10011. The set of amplified X-STRs was designed to include groups of closely linked markers (DXS101–DXS7424 and DXS6789–DXS6801–DXS6809) to generate highly informative haplotypes for kinship testing. A population genetics study of the 12 X-STRs was conducted in a northwestern Italian population sample (n=160, 80 women and 80 men). A diallelic pattern at locus DXS6789 was observed in one man.

Differential Greek and northern African migrations to Sicily are supported by genetic evidence from the Y chromosome

The presence or absence of genetic heterogeneity in Sicily has long been debated. Through the analysis of the variation of Y-chromosome lineages, using the combination of haplogroups and short tandem repeats from several areas of Sicily, we show that traces of genetic flows occurred in the island, due to ancient Greek colonization and to northern African contributions, are still visible on the basis of the distribution of some lineages. The genetic contribution of Greek chromosomes to the Sicilian gene pool is estimated to be about 37% whereas the contribution of North African populations is estimated to be around 6%.In particular, the presence of a modal haplotype coming from the southern Balkan Peninsula and of its one-step derivates associated to E3b1a2-V13, supports a common genetic heritage between Sicilians and Greeks. The estimate of Time to Most Recent Common Ancestor is about 2380 years before present, which broadly agrees with the archaeological traces of the Greek classic era. The Eastern and Western part of Sicily appear to be significantly different by the χ2-analysis, although the extent of such differentiation is not very high according to an analysis of molecular variance. The presence of a high number of different haplogroups in the island makes its gene diversity to reach about 0.9. The general heterogeneous composition of haplogroups in our Sicilian data is similar to the patterns observed in other major islands of the Mediterranean, reflecting the complex histories of settlements in Sicily.

Linkage and linkage disequilibrium analysis of X-STRs in Italian families

Twenty X-chromosomal short tandem repeat (STR) loci were typed in 80 families of Italian descent, composed by mother and two or more sons, for a total of 93 meiosis. The analyzed X-STR panel included six clusters of closely linked markers (each spanning<3cM): DXS10135-DXS10148-DXS8378 (Xp22); DXS7132-DXS10074-DXS10079 (Xq12); DXS6801-DXS6809-DXS6789 (Xq21); DXS7424-DXS101 (Xq22); DXS10103-HPRTB-DXS10101 (Xq26); DXS8377-DXS10134-DXS7423-DXS10146 (Xq28). Recombination fractions between pairs of markers calculated by pedigree analysis were compared with those obtained from the second-generation Rutgers combined linkage-physical map of the human genome. The observed differences confirm that recombination is not homogeneous along the X chromosome and that the conventional subdivision of X-STRs in four groups of completely unlinked markers cannot be regarded as true. Significant linkage disequilibrium was found between markers DXS6801 and DXS6809 (p=0.017). The effect on likelihood calculations of inferring haplotype frequencies from allele distributions rather than haplotype count in the relevant population was evaluated.

Allele and haplotype diversity of X-chromosomal STRs in Ivory Coast

Twenty-one X-chromosomal short tandem repeat (STR) loci, including the six clusters of linked markers DXS10148–DXS10135–DXS8378 (Xp22), DXS7132–DXS10079–DXS10074 (Xq12), DXS6801–DXS6809–DXS6789 (Xq21), DXS7424–DXS101 (Xq22), DXS10103–HPRTB–DXS10101 (Xq26), DXS8377–DXS10146–DXS10134–DXS7423 (Xq28) and the loci DXS6800, GATA172D05 and DXS10011 were typed in a popula3tion sample from Ivory Coast (n = 125; 51 men and 74 women). Allele and haplotype frequencies as well as linkage disequilibrium data for kinship calculations are provided. On the whole, no significant differences in the genetic variability of X-STR markers were observed between Ivorians and other sub-Saharan African populations belonging to the Niger–Kordofanian linguistic group.

Analysis of 11 tetrameric STRs in wild boars for forensic purposes.

STR profiling of animal species has a wide range of applications, including forensic identification, wildlife preservation, veterinary public health protection and food safety. We tested the efficacy of a multiplex PCR-based assay including 11 porcine-specific tetrameric STRs in a population sample of wild boars (n=142) originating from Piedmont (North West Italy). Multiple deviations from Hardy-Weinberg expectations were observed, mostly due to a reduction in observed heterozygosity indicative of a high degree of inbreeding. A value of θ of 0.046 and an inbreeding coefficient of 0.089 were estimated. Combined power of discrimination and probability of exclusion values for the STR panel were 0.9999999999996 and 0.99989. In order to test the suitability of the method for meat traceability purposes, a domestic pig reference sample (n=412), consisting of commercial lines commonly used in the meat production process, was also typed. A Bayesian cluster analysis carried out using the observed genotypes, showed a percentage of correct subspecies assignment of individual samples of 0.974 for wild boars and 0.991 for pigs, thus demonstrating the usefulness of the multiplex STR-typing system for discrimination purposes.

Incestuous paternity detected by STR-typing of chorionic villi isolated from archival formalin-fixed paraffin-embedded abortion material using laser microdissection

ABSTRACT: Microscopic examination of a blood clot expelled by a physically and mentally disabled woman taken to the emergency room because of genital bleeding revealed the presence of chorionic villi encircled by decidua, hemorrhage, and necrosis. In order to identify the father of the product of conception, sections of formalin‐fixed, paraffin‐embedded abortion material were subjected to laser microdissection: DNA extraction from chorionic villi selectively isolated from the surrounding tissues allowed successful STR‐typing of fetal cells, which was otherwise prevented by excess maternal DNA. The large number of homozygous genotypes in the fetal profile suggested incestuous paternity. Analysis of reference DNA samples from male relatives excluded the womans father, paternal grandfather, and maternal grandfather, whereas the obligate paternal alleles of the fetus were constantly present in the genotypes of the womans brother, clearly demonstrating brother–sister incest (probability of paternity >99.99999%).

Scanning electron microscope study of the lung in drowning.

The authors describe the results obtained using the scanning electron microscope (SEM) to study drowned lungs and control lungs. Results are compared with a previous study carried out using laboratory animals. The results from both studies are analogous, in the absence of chronic pulmonary emphysema. The diagnosis of chronic pulmonary emphysema is simple with the SEM even when dealing with autoptic material obtained 24 to 48 h after death, but the diagnosis of drowning becomes difficult in lungs with chronic emphysema.

Scanning Electron Microscopic Ultrastructural Alterations of the Pulmonary Alveolus in Experimental Drowning

Scanning electron microscopic structural and ultrastructural alterations of alveolar wall in experimental drowning are described. The results obtained confirm the literatures data. Peculiar microlesions affecting Type I alveolar cells, the basement membrane, and sometimes the capillary endothelium could also be observed. Finally, Type II alveolar cells show alterations which could be related with a possible direct action of the drowning liquid.