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This article discusses a study that aims to demonstrate the scientific validity of a novel cell-based non-invasive prenatal testing (cbNIPT) method for detecting fetal copy number variants (CNVs) using single cell sequencing of circulating extravillous trophoblasts (cEVTs). The study enrolled 1388 high-risk pregnancies and found a screen positive rate of 18.9% for aneuploidies and 11.2% for pCNVs. The results showed that cbNIPT was able to detect pCNVs <1 Mb in size, which is below the resolution of cell-free DNA screening. The authors conclude that analyzing cEVTs from maternal blood could significantly reduce the residual risk for pCNVs in early gestational weeks. [Extracted from the article]

Radiocarbon is one of the most widespread radionuclides in nature. Although it is probably best known for dating in archaeology, in the case of the general public, it represents a useful tracer to study our environment, both in the past and nowadays. For instance, carbonaceous particles, which are in many cases the most abundant among aerosols constituents, are believed to play a major role in both health and climatic effects of aerosols. In particular, measurement of radiocarbon concentration in particulate matter samples can give information on the contributions of the fossil fuels combustion and of natural sources to the carbonaceous fraction in aerosols. These measurements are especially effective when separately performed on different carbonaceous fractions, like elemental and organic carbon (EC and OC, respectively). Past climate is also studied thanks to old archives, as e.g. marine sediments can be. In this case, instead of radiocarbon dating the bulk sediment, a reliable method to fix chronological markers is represented by dating foraminifera tests of CaCO3 picked from different layers in the sediment. Both the aforementioned applications are characterized by the fact that the samples that can be collected for 14C measurements are typically very small, i.e. few mg or less (before any treatment). Accelerator Mass Spectrometry (AMS) is thus the only technique that can be applied to measure radiocarbon in such samples. Anyway, measurements cannot be so straightforward. In the case of the measurement of radiocarbon concentration in aerosol samples, a preparation line especially dedicated to the extraction of only the carbonaceous fraction of interest is mandatory. Actually, this line should include a combustion oven, from which either total carbon or EC and OC can separately evolve, and a system of traps to purify and collect the CO2. In the case of foraminifera tests (inorganic carbon), special care must be taken in the pre-treatment phase: foraminifera can be contaminated by heterogeneous materials, including organic matter too. Pre-treatment should thus remove all the possible contaminations without losing too much mass of the samples. Here we present an overview of the environmental radiocarbon applications the INFN-LABEC laboratory in Florence is involved in. 14C is measured by AMS, using the dedicated beam line installed at the 3 MV Tandem accelerator. In particular, details about the hardware and the experimental procedures are given.

Objectives: To quantify mediastinal shift in isolated congenital diaphragmatic hernia (CDH), by the introduction of a new ultrasonographic (US) marker, defined as mediastinal shift angle (MSA) and to evaluate its ability in predicting postnatal survival at discharge.Methods: Twenty-four consecutive fetuses from singleton pregnancies with isolated left-sided CDH were included in the study group and then subdivided into group A (16 survivors) and group B (8 nonsurvivors). The study group was matched with a control group of 95 fetuses from singleton pregnancies free from structural and/or chromosomal anomalies. On the same US stored images commonly used for lung-to-head ratio (LHR) measurement, a landmark line was drawn from a point on the posterior face of the vertebral body, splitting it into two equal parts, to the mid-posterior surface of the sternum. Another landmark line was then traced from the same point of the vertebral body to touch tangentially the lateral wall of the right atrium. The angle between these two lines was used to quantify mediastinal shift and called "mediastinal shift angle" (MSA).Results: Median MSA was significantly different between group A (34.3° range 29.3-45.9°) and group B (42.7° range 34.1-58.9°) (p < .001) and between study group as a whole and the control group (19° range 13.8-25.9°) (p < .001). Statistical analysis confirmed an inverse correlation between MSA values and survival (p = .004). The best cutoff value for MSA was 43.7°, which demonstrated the highest discriminatory power (sensitivity 63%; specificity 93.75%).Conclusions: In fetuses with isolated CDH, the mediastinal shift may be quantified using mediastinal shift angle (MSA) and this US marker, similarly to the widely accepted and used US prenatal prognostic indicators (LHR and O/E LHR), seems to reliably predict survival. [ABSTRACT FROM AUTHOR]

It is reported that many infants with CDH have evidence of brain injury on postnatal brain magnetic resonance imaging (MRI). Results HT

To describe ultrasound features of fetal ovarian cysts as reported by the original ultrasound examiner and according to IOTA terminology. Ovarian cysts with low level content could be managed expectantly, whereas ovarian cysts with other cyst content should be managed with postnatal surgery, due to the high risk of necrosis at final histology. [Extracted from the article]

Exploiting the anomalous behaviour of the atmospheric radiocarbon concentration in the years after 1955 (so-called 'Bomb Peak'), an alleged painting by Fernard Léger was unambiguously proven to be a fake just by dating the canvas support. Some art historians had questioned the authenticity of the painting, and their suspicions were fuelled by some scientific examinations of the paint materials (X-ray radiography, SEM-EDS), compared to those of another work unquestionably attributed to Léger. The decisive argument to prove that it was a fake was provided by the radiocarbon date obtained from a sample of canvas of the painting, using Accelerator Mass Spectrometry at the INFN-Labec laboratory in Florence. Beyond any doubt, the cotton plant from which the canvas was produced was cut no earlier than 1959, i.e. four years after Léger's death, thus definitely confirming the concerns of a fake. [ABSTRACT FROM AUTHOR]

Since installation of the new accelerator at INFN-LABEC in Florence in 2004, the workload has progressively increased in the radiocarbon dating laboratory, requiring a faster sample preparation throughput and greater versatility to allow for a larger variety of treated materials. The "standard" sample preparation line is based on an elemental analyzer (EA) for the combustion of the pretreated samples, and a vacuum line where the CO2 is collected and then converted to graphite. This line has been recently redesigned while maintaining the EA, since this instrument provides us reliable and fast sample combustion and separation of gases. The volumes were optimized and all the mechanical parts (e.g. the fittings) were changed in order to improve the vacuum level, thus decreasing the possibility of contamination; finally, the number of graphitization reactors was doubled (from 4 to 8). In those rare cases involving samples characterized by a complex nearly graphitic structure (e.g. burnt residues), the EA might not guarantee a complete combustion. For these samples, we successfully tested the new sample preparation line that has been recently installed at LABEC and especially dedicated to aerosol samples. This line is equipped with a custom-made combustion oven able to heat to 1000 °C. The subsequent gas separation is accomplished by chemical and thermal traps. As an example, the dating of organic matter collected from an Etruscan bronze statue will be presented and discussed. [ABSTRACT FROM AUTHOR]

Abstract: The use of radiocarbon in forensics is by now widespread, thanks to the so-called bomb peak, which makes it possible to perform high-precision dating. Since 1955, 14C concentration in the atmosphere had strongly increased due to nuclear explosions, reaching its maximum value in 1963–1965. After the Nuclear Test Ban Treaty, 14C started to decrease as a consequence of the exchanges between atmosphere and the other natural carbon reservoirs. Nowadays, it is still slightly above the pre-bomb value. The work presented in this paper is based on the idea of exploiting the bomb peak to “precisely” date works of contemporary art, with the aim at identifying possible fakes. We analysed two kinds of materials from the 20th century: newspapers and painting canvases. Newspaper samples were taken because they might in principle be considered to represent dated samples (considering the date on the issues). Our data (28 samples) show a trend similar to atmospheric data in the literature, although with some differences; the paper peak is flatter and shifted towards more recent years (about five years) with respect to the atmospheric data. This can be explained by taking paper manufacturing processes into account. As to the canvas samples, the measured 14C concentrations were generally reasonably consistent with the expected concentrations (based on the year on the paintings). However, this does not indicate that the interpretation of the results is simpler and more straightforward. Obviously, we only measure the 14C concentration of the fibre used for the canvas, which does not necessarily measure the date the painting was manufactured. In this paper, sample preparation and experimental results will be discussed, in order to show the potential as well as the limitations of radiocarbon to date contemporary art. [Copyright &y& Elsevier]