Monitoring of Oxygen in Simulated Electrolytic Reduction Salt of Pyroprocessing Using Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) was explored as a method of monitoring oxygen (O) concentration in electrolytic reduction salt of pyroprocessing. Simulated salt samples were fabricated, and each sample was put in a transparent and sealed vial filled with argon gas. An Nd:YAG laser pulse was applied to the sample through the vial surface, and the optical emission spectrum was measured. O(I) 777.2 nm lines were clearly identified in the spectrum of a sample containing Li2O, and the intensity of the O peak and the intensity ratio of O and lithium (Li) peaks, in which Li was used as the normalization, increased linearly as the O concentration in the salt sample was increased. The limit of detection and root mean square error were calculated for the cases of O peak area, O peak height, peak area ratio of O–Li, and the peak height ratio of O–Li, and all the cases could indicate that the O concentration in the electrolytic reduction salt was out of normal range. Our result shows that LIBS has the possibility to be used as a method for monitoring of O in electrolytic reduction salt.

DNA degradation in human teeth exposed to thermal stress

Human identification from burned remains poses a challenge to forensic laboratories, and DNA profiling is widely used for this purpose. Our aim was to evaluate the effect of temperature on DNA degradation in human teeth. Thirty teeth were exposed to temperatures of 100, 200, or 400 °C for 60 min. DNA was quantified by Real-Time qPCR (Quantifiler Human DNA Quantification Kit) and fluorescence spectroscopy (Qubit 3.0 Fluorometer). DNA degradation was evaluated by using STR markers (AmpFLSTR Identifiler Plus PCR Amplification Kit) to determine the allele and locus dropout, inter-locus balance, and degradation slope (observed (Oa) to expected (Ea) locus peak height ratio against the molecular weight). Most of the genomic DNA was degraded between 100 °C and 200 °C. At 100 °C, locus dropout ratios showed significant differences between the largest loci (FGA, D7S820, D18S51, D16S539, D2S1338 and CSF1PO) and amelogenin. Inter-locus balance values significantly differed between all dye channels except between NED and PET. The dropout ratio between D18S51 (NED) and amelogenin (PET) can be recommended for the evaluation of DNA degradation. The Oa/Ea regression model can predict locus peak heights in DNA degradation (R2 = 0.7881). These findings may be useful to assess the reliability of DNA typing for human identification in teeth subjected to prolonged incineration.

A Beckwith-Wiedemann syndrome case with de novo 24 Mb duplication of chromosome 11p15.5p14.3

Background Molecular genetic testing for the 11p15-associated imprinting disorder Beckwith-Wiedemann syndrome (BWS) is challenging because of the molecular heterogeneity and complexity of the affected imprinted regions. An integrated molecular approach to analyze the epigenetic-genetic alterations is required for accurate diagnosis of BWS. Case presentation: We reported a Chinese case with BWS detected by SNP array analysis and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA). The genetic analysis showed a de novo duplication of 24 Mb at 11p15.5p14.3 is much longer than ever reported. MS-MLPA showed copy number changes with a peak height ratio value of 1.5 (three copies) at 11p15. The duplication of paternal origin with increase of methylation index of 0.68 at H19 and decreased methylation index of 0.37 at KCNQ1OT1. Conclusion Combined chromosome microarray analysis and methylation profiling provided reliable diagnosis for this paternally derived duplication of BWS. The phenotype associated with 11p15 duplications depends on the size, genetic content, parental inheritance and imprinting status. Identification of these rare duplications is crucial for genetic counselling.

Calculating likelihoods and likelihood ratios at SNPs-based mixtures. A reappraisal of the binomial inference, as applied to forensic identity tests

Single nucleotide polymorphisms (SNPs) are useful forensic markers. When a SNPs-based forensic protocol targets a body fluid stain, it returns elementary evidence regardless of the number of individuals that might have contributed to the stain deposition. Therefore, drawing inference from a mixed stain with SNPs is different than drawing it while using multinomial polymorphisms. We here revisit this subject, with a view to contribute to a fresher insight into it. First, we manage to model conditional semi-continuous likelihoods in terms of matrices of genotype permutations vs number of contributors (NTZsc). Secondly, we redefine some algebraic formulas to approach the semi-continuous calculation. To address allelic dropouts, we introduce a peak height ratio index (‘h’, or: the minor read divided by the major read at any NGS-based typing result) into the semi-continuous formulas, for they to act as an acceptable proxy of the ‘split drop’ (Haned et al, 2012) model of calculation. Secondly, we introduce a new, empirical method to deduct the expected quantitative ratio at which the contributors of a mixture have originally mixed and the observed ratio generated by each genotype combination at each locus. Compliance between observed and expected quantity ratios is measured in terms of (1-χ2) values at each state of a locus deconvolution. These probability values are multiplied, along with the h index, to the relevant population probabilities to weigh the overall plausibility of each combination according to the quantitative perspective. We compare calculation performances of our empirical procedure (NITZq) with those of the EUROFORMIX software ver. 3.0.3. NITZq generates LR values a few orders of magnitude lower than EUROFORMIX when true contributors are used as POIs, but much lower LR values when false contributors are used as POIs. NITZ calculation routines may be useful, especially in combination with mass genomics typing protocols.

A Beckwith-Wiedemann syndrome case with de novo 24 Mb duplication of chromosome 11p15.5p14.3

Background: Molecular genetic testing for the 11p15-associated imprinting disorder Beckwith-Wiedemann syndrome(BWS) is challenging because of the molecular heterogeneity and complexity of the affected imprinted regions. An integrated molecular approach to analyze the epigenetic-genetic alterations is required for accurate diagnosis of BWS.Case presentation: We reported a Chinese case with BWS detected by SNP array analysis and methylation-specific multiplex ligation-dependent probe amplification (MS‑MLPA). The genetic analysis showed a de novo duplication of 24 Mb at 11p15.5p14.3 is much longer than ever reported. MS-MLPA showed copy number changes with a peak height ratio value of 1.5(three copies) at 11p15. The duplication of paternal origin with increase of methylation index of 0.68 at H19 and decreased methylation index of 0.37 at KCNQ1OT1. Conclusion: Combined chromosome microarray analysis and methylation profiling provided reliable diagnosis for this paternally derived duplication of BWS. The phenotype associated with 11p15 duplications depends on the size, genetic content, parental inheritance and imprinting status. Identification of these rare duplications is crucial for genetic counselling.

A Beckwith-Wiedemann Syndrome Case with de novo 24 Mb Duplication of Chromosome 11p15.5-14.3

BackgroundMolecular genetic testing for the 11p15-associated imprinting disorder Beckwith-Wiedemann syndrome(BWS) is challenging because of the molecular heterogeneity and complexity of the affected imprinted regions. An accurate diagnosis of BWS requires a complete molecular method to analyze epigenetic changes.Case presentationWe reported a Chinese case with BWS detected by SNP array analysis and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA). The genetic analysis showed a de nove duplication of 24 Mb at 11p15.5-14.3 is much longer than ever reported. MS-MLPA showed copy number changes with a peak height ratio value of 1.5(three copies) at 11p15. The duplication of paternal origin withincrease of methylation index of 0.68 at H19 and decreased methylation index of 0.37 at KCNQ1OT1.ConclusionCombined chromosome microarray analysis and methylation profiling provided reliable diagnosis for this paternally derived duplication of BWS. The phenotype associated with 11p15 duplications depends on the size, genetic content, parental inheritance and imprinting status. Identification of these rare duplications is crucial for genetic counselling.

Quantitative determination of titanium tetrachloride and dichloromethane by Raman spectroscopy using carbon disulfide as an internal standard

Raman spectroscopy with an internal standard and peak height ratio was applied for the quantitative analysis of dichloromethane and titanium tetrachloride.

Resistance to Thrombomodulin but Not to Activated Protein C in Cirrhotic Patients

Introduction: Cirrhotic patients have an impairment of haemostasis. They are exposed to both thrombotic and bleeding events. Global coagulation tests as thrombin generation assays (TGA) could be informative to evaluate the coagulation step in this context. When the protein C (PC) pathway is sensibilised using thrombomodulin (TM), a « resistance » to the PC pathway appears, increasing with the severity of the hepatopathy. Nevertheless, patients with cirrhosis have a decrease protein C level which is probably involved in this « resistance ». The aim of this study was to compare the TGA with thrombomodulin or activated PC (aPC) to by-pass the PC defect. Materials and Methods: Patients prospectively included were confirmed cirrhotic patients (prothrombin time <70% and/or liver dysmorphia and/or fibroscan> 20 kPa and/or histology and/or association of portal hypertension and liver failure). Patients were exclusively male, free of hepatocellular carcinoma and were not anticoagulated. Patients with on-going infection or inflammatory complication were excluded. None of them had a thromboembolic event or a familial history of thromboembolism. TGA were performed in the presence/absence of TM and in the presence/absence of aPC, with previously determined concentrations inhibiting 50% of endogeneous thrombin potential (ETP) of healthy plasmas. Results were expressed as ratios with/without TM or with/without aPC. Statistical analysis was based on Kruskal-Wallis test and Dunn's post test. All tests were performed in triplicate. The study met all ethical autorizations. Results: We enrolled 15 Child-Pugh A, patients 11 Child-Pugh B, 10 Child-Pugh C and 14 healthy controls. Comparatively to controls, PC, protein S (PS) and FVIII levels were significantly decreased in cirrhotic patients. ETP ratio with TM were statistically different between controls vs Child-Pugh B (p<0.05) and controls vs Child-Pugh C (p<0.01). Peak height ratio with TM were statistically different between controls vs Child-Pugh A (p<0.05), controls vs Child-Pugh B (p<0.01) and controls vs Child-Pugh C (p<0.01). All these significant differences disappear when we used aPC instead of TM, suggesting that the « resistance » to the soluble TM is due, at least partially, to the acquired deficiency in PC. Discussion and Conclusions: The main finding of this study is that the acquired protein C deficiency actively participate to the « resistance » to soluble thrombomodulin in cirrhotic patients. These data are in line with studies of the Tripodi group who have also demonstrated a participation of the protein C deficiency in the resistance to thrombomodulin and Protac. Further studies are needed to evaluate the association between this biological phenotype and thrombotic events. Disclosures No relevant conflicts of interest to declare.