ABSTRACT
Dosimetry and spectrometry measurements have been carried out in the thermal column of the research fast reactor RSV-TAPIRO (ENEA-Casaccia, Rome) in order to investigate its suitability for irradiation of cells or mice, with a view to research in the interests of boron neutron capture therapy (BNCT). The thermal column consists of a graphite moderator (40 cm thick) containing a lead shield (13 cm thick) in order to shield reactor background. The irradiation volume, inside this structure, has cubic shape (18 x 18 x 18 cm3). Besides measurements of fluence and dose rates in air or in phantom performed with thermoluminescence dosemeters (TLDs) and using the activation technique, dose and fluence profiles have been generated using a method based on gel dosemeters analysed with optical imaging. To check the consistency of the results, spectrometry measurements in the same irradiation volume have been performed by means of bubble detectors.
Subject(s)
Boron Neutron Capture Therapy/instrumentation , Equipment Failure Analysis/methods , Neutrons/therapeutic use , Radiation Protection/instrumentation , Radiometry/methods , Radiotherapy Planning, Computer-Assisted/instrumentation , Animals , Body Burden , Boron Neutron Capture Therapy/methods , Equipment Design , Gamma Rays/therapeutic use , Hot Temperature , Humans , Italy , Nuclear Reactors , Radiobiology/instrumentation , Radiometry/instrumentation , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Relative Biological Effectiveness , Reproducibility of Results , Risk Assessment/methods , Sensitivity and SpecificityABSTRACT
DNA samples from 465 blood donors living in 7 towns of Sicily, the largest island of Italy, have been collected according to well defined criteria, and their genetic heterogeneity tested on the basis of 9 autosomal microsatellite and mitochondrial DNA polymorphisms for a total of 85 microsatellite allele and 10 mtDNA haplogroup frequencies. A preliminary account of the results shows that: a) the samples are genetically heterogeneous; b) the first principal coordinates of the samples are correlated more with their longitude than with their latitude, and this result is even more remarkable when one outlier sample (Butera) is not considered; c) distances among samples calculated from allele and haplogroup frequencies and from the isonymy matrix are weakly correlated (r = 0.43, P = 0.06) but such correlation disappears (r = 0.16) if the mtDNA haplogroups alone are taken into account; d) mtDNA haplogroups and microsatellite distances suggest settlements of people occurred at different times: divergence times inferred from microsatellite data seem to describe a genetic composition of the town of Sciacca mainly derived from settlements after the Roman conquest of Sicily (First Punic war, 246 BC), while all other divergence times take root from the second to the first millennium BC, and therefore seem to backdate to the pre-Hellenistic period. A more reliable association of these diachronic genetic strata to different historical populations (e.g. Sicani, Elymi, Siculi), if possible, must be postponed to the analysis of more samples and hopefully more informative uniparental DNA markers such as the recently available DHPLC-SNP polymorphisms of the Y chromosome.
Subject(s)
DNA, Mitochondrial/genetics , Genetic Markers , Microsatellite Repeats , Polymorphism, Genetic , Alleles , Female , Gene Frequency , Genetics, Population , Humans , Male , Names , Phylogeny , SicilyABSTRACT
Genetic analysis was performed on 72 Italian A-T families ascertained through 91 probands. The frequency of the A-T gene was estimated through Dahlberg's formula, which uses the frequencies of first cousin marriages among the patients' parents and in the general population were obtained from the collection of Catholic Church dispensations for the period 1910-1964. Accurate estimates of the disease frequency were made by subdividing data into 5-year periods and between provinces, in order to take into account temporal (decrease over time) and spatial (higher frequency in Southern Italy) heterogeneity. The estimate of the gene frequency for the whole sample was q = 0.012 +/- 0.0065, corresponding to a heterozygote frequency of 2.34% and to a disease frequency of 1 in 7090. When considering q before and after 1970, there was an apparent increase of heterozygote frequency from 1.69 to 3.43%, perhaps due to a better ascertainment of the disease in the latter period. A segregation ratio of 0.249 +/- 0.043 was obtained by analyzing the offspring of the 72 families under the model of incomplete multiple selection. This value is not significantly different from 0.25, as expected for an autosomal recessive disease.
Subject(s)
Ataxia Telangiectasia/genetics , Adult , Ataxia Telangiectasia/epidemiology , Child , Consanguinity , Humans , Incidence , Italy/epidemiologyABSTRACT
Surname distributions were studied in order to reconstruct human migration patterns. Zones of sharp change in surname frequencies--presumably barriers to gene flow--were detected by the statistical technique of wombling (Barbujani et al. 1989), using data from consanguineous marriages (1910-64) collected from 280 Italian dioceses which we grouped into 80 provinces. The 28 observed surname boundaries were compared with physical (geographical) and cultural (linguistic) barriers, and with boundaries detected from distributions of 57 alleles in the same territorial subdivisions. Genetic and surname boundaries had similar locations, as expected given the analogy in the inheritance mechanism of genes and surnames. Physical barriers seemed to be the main cause of gene flow reduction. However, cultural factors alone (e.g. linguistic ones) also determined barriers that delimited areas of homogeneous gene (and surname) frequency probably due to increased endogamy. The observed similarity between spatial patterns of surnames, genes and languages supports the hypothesis of the co-evolution of genetic and linguistic variation.
