Image cytometry DNA ploidy analysis: Correlation between two semi-automated methods.

Background And Objectives: Quantitation of cell DNA content, DNA ploidy, has been established as a research and prognostic technique for decades. A variety of instruments have been used although only a few commercially available systems have established quality assurance and published outcome data. The aim of this study was to compare two automated systems.

Karyomegalic interstitial nephritis and DNA damage-induced polyploidy in Fan1 nuclease-defective knock-in mice.

The Fan1 endonuclease is required for repair of DNA interstrand cross-links (ICLs). Mutations in human Fan1 cause karyomegalic interstitial nephritis (KIN), but it is unclear whether defective ICL repair is responsible or whether Fan1 nuclease activity is relevant. We show that Fan1 nuclease-defective (Fan1(nd/nd)) mice develop a mild form of KIN.

Quantification of lymph nodes in the central compartment of the neck: a cadaveric study.

Differentiated thyroid cancer (DTC) accounts for over 90 % of thyroid malignancies, and is frequently associated with central neck compartment nodal metastasis that requires a therapeutic central compartment neck dissection (CCND) for clinically evident nodes. Current knowledge on the expected lymph node yield from a CCND is limited, compared with data on the lateral neck. The aim of our study was to accurately quantify nodal yield from the cadaveric central neck compartment.

Predictive value of dysplasia grading and DNA ploidy in malignant transformation of oral potentially malignant disorders.

Dysplasia grading is widely used to assess risk of transformation in oral potentially malignant disorders despite limited data on predictive value. DNA ploidy analysis has been proposed as an alternative. This study examines the prognostic value for both tests used in a routine diagnostic setting to inform clinical management.

Investigation of isotopic linkages between precursor materials and the improvised high explosive product hexamethylene triperoxide diamine.

The results of isotope ratio mass spectrometry (IRMS) on hexamethylene triperoxide diamine (HMTD) and its precursor hexamethylenetetramine (hexamine) is presented. HMTD was prepared from hexamine using several different sources of hexamine under both controlled laboratory conditions and in field experiments that represent the less controlled conditions that are likely to be observed in forensic casework scenarios. Precursor and product carbon isotope δ values consistently fit a linear relationship regardless of precursor or conditions.

Results of four inter-laboratory comparisons provided by the Forensic Isotope Ratio Mass Spectrometry (FIRMS) network.

Between 2004 and 2008 the Forensic Isotope Ratio Mass Spectrometry (FIRMS) network organised four Inter-Laboratory Camparison excercises with the aim of harmonising and validating isotopic measurements to be used for forensic applications. The samples distributed comprised materials of potential forensic interest such as packaging and pharmaceuticals to be analysed for delta2H, delta13C, delta15N and delta18O composition. As many as 30 international laboratories participated in these comparisons.

N(2): a potential pitfall for bulk (2)H isotope analysis of explosives and other nitrogen-rich compounds by continuous-flow isotope-ratio mass spectrometry.

Observations made during the (13)C isotope analysis of gaseous CO(2) in the simultaneous presence of argon in the ion source of the isotope ratio mass spectrometer prompted us to investigate what influence the simultaneous presence of nitrogen would have on both accuracy and precision of bulk (2)H isotope analysis of nitrogen-rich organic compounds. Initially an international reference material, IAEA-CH7, was mixed with silver nitrate in various ratios to assess the impact that N(2) evolved from the pyrolysis of nitrogen-rich organic compounds would have on measured delta(2)H-values of IAEA-CH7. In a subsequent experiment, benzoic acid was mixed with silver nitrate to mimic the N:H ratio of organic-rich nitrogen compounds such as cellulose nitrate and RDX.

Investigation of isotopic linkage between precursor and product in the synthesis of a high explosive.

In criminal proceedings involving illegally manufactured substances, evidence demonstrating the manufacture is required for successful prosecution. In many circumstances the presence of manufacturing equipment and 'recipes' are clear indicators. However establishing chemical links between starting materials and products would be beneficial additional evidence in such circumstances.

Evaluation of preliminary isotopic analysis (13C and 15N) of explosives A likelihood ratio approach to assess the links between semtex samples.

Currently, the use of isotopic ratio as corroborative evidence in criminal trials is explored. Beyond the analytical challenges that have been reported elsewhere, the crucial issue of the interpretation of analytical results in a fair and balanced way remains poorly documented. The aim of this paper is to propose a likelihood ratio approach for the evaluation of stable isotope data acquired from semtex samples.