[Determination of Dichloromethane in Blood with Headspace Gas Chromatography and Gas Chromatography-Mass Spectrometry].

Objective: To establish a method for qualitative determination of dichloromethane (DCM) in blood by gas chromatography-mass spectrometry (GC-MS) and quantitative determination of DCM in blood by headspace gas chromatography (HS-GC), and to provide reliable support for forensic examination and analysis of poisoning or deaths caused by DCM. Methods: 0.5 mL blood sample was collected, added into headspace vial with chloroform as the internal standard, and processed by heating at 65 °C and evacuation treatment. The intermediate gas in the headspace vial was analyzed by GC-MS for qualitative validation of the method and by HS-GC for quantitative validation of the method. The method was then applied in forensic case analysis. Results: Qualitative validation of the examination method by GC-MS found that the chromatographic peak and mass spectral characteristic ions were specific in samples added with DCM, and that no interference was observed in the blank negative samples. The limit of detection (LOD) was 5 µg/mL. Quantitative method validation by HS-GC found that the chromatographic peak of DCM was well separated from those of eight other volatile compounds, with the resolution>1.5 in all cases; the lower limit of quantification (LOQ) was 20 µg/mL and good linearity was shown within the range of 20 and 1000 µg/mL, R>0.999; the intra-day test precision and inter-day test precision were good (relative standard deviation, or RSD<15% for both) and test accuracy was high (relative error, or δ<15%). With the method established in the study, DCM was detected successfully in the blood of two fatal cases caused by DCM poisoning, with the blood concentration being 470 µg/mL and 915 µg/mL, respectively. Conclusion: This method is shown to be a rapid, stable and accurate approach to the qualitative and quantitative forensic and toxicological analysis of DCM in blood in DCM poisoning cases or deaths caused by DCM.

[Analysis of clinical features and SLC25A13 gene mutations in a family affected with neonatal intrahepatic cholestasis].

OBJECTIVE: To analyze the clinical features and potential mutations of the SLC25A13 gene in a boy affected with neonatal intrahepatic cholestasis. METHODS: Clinical data and peripheral venous blood sample of the child, and peripheral venous blood samples of both parents, were collected. All coding exons of the SLC25A13 gene were amplified with PCR and subjected to direct DNA sequencing. RESULTS: The boy was found to be a compound heterozygote carrying c.851_854delGTAT and IVS16ins3kb mutations of the SLC25A13 gene, which were respectively inherited from his mother and father. CONCLUSION: Based on its clinical and genetic features, the patient was diagnosed with neonatal intrahepatic cholestasis caused by citrin deficiency.

Development of 20 microsatellite markers for Solenocera crassicornis and their cross-species application in Solenocera melantho.

Twenty microsatellite markers were isolated and characterized for Solenocera crassicornis from a (GT)13-enriched genomic library. Their polymorphisms were investigated using 44 wild individuals from the South Yellow Sea. Our investigation revealed that all the markers were polymorphic. The number of alleles per locus varied from 6 to 19 with an average of 12.35. The observed and expected heterozygosities ranged from 0.400 to 0.977 and from 0.609 to 0.940, with averages of 0.788 and 0.859, respectively. Four loci significantly deviated from Hardy-Weinberg equilibrium after Bonferroni's correction. Cross-species amplification was also conducted in Solenocera melantho collected from the East China Sea. The result showed that 14 loci could be amplified from Solenocera melantho DNAs. These polymorphic markers would be useful for assessment of genetic variation and population structure of S. crassicornis and S. melantho.

Isolation and characterization of new 24 microsatellite DNA markers for golden cuttlefish (Sepia esculenta).

Twenty-four microsatellite DNA markers were isolated and characterized for golden cuttlefish (Sepia esculenta) from a (GT)(13)-enriched genomic library. Loci were tested in 48 individuals from Jiaozhou bay of China. The numbers of alleles per locus ranged from two to 25 with an average of 10.3. The observed and expected heterozygosities ranged from 0.063 to 0.896 and from 0.137 to 0.953, with averages of 0.519 and 0.633, respectively. Six loci significantly deviated from Hardy-Weinberg equilibrium after Bonferroni's correction and no significant linkage disequilibrium between loci pairs was detected. These microsatellite markers would be useful for analyzing the population genetic structure to make conservation and management decisions for S. esculenta.