Forensic Pathological Diagnosis of Acute and Old Myocardial Infarction Using Fourier Transform Infrared Spectroscopy / 法医学杂志

OBJECTIVES@#Fourier transform infrared spectroscopy (FTIR) was used to analyze myocardial infarction tissues at different stages of pathological change to achieve the forensic pathology diagnosis of acute and old myocardial infarction.@*METHODS@#FTIR spectra data of early ischemic myocardium, necrotic myocardium, and myocardial fibrous tissue in the left ventricular anterior wall of the sudden death group of atherosclerotic heart disease and the myocardium of the normal control group were collected using hematoxylin-eosin (HE) and immunohistochemistry (IHC) staining as a reference, and the data were analyzed using multivariate statistical analysis.@*RESULTS@#The mean normalized spectra of control myocardium, early ischemic myocardium and necrotic myocardium were relatively similar, but the mean second derivative spectra were significantly different. The peak intensity of secondary structure of proteins in early ischemic myocardium was significantly higher than in other types of myocardium, and the peak intensity of the α-helix in necrotic myocardium was the lowest. The peaks of amide Ⅰ and amide Ⅱ in the mean normalized spectra of myocardial fibrous tissue significantly shifted towards higher wave numbers, the peak intensities of amide Ⅱ and amide Ⅲ were higher than those of other types of myocardium, and the peak intensities at 1 338, 1 284, 1 238 and 1 204 cm-1 in the mean second derivative spectra were significantly enhanced. Principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) showed that FTIR could distinguish different types of myocardium.@*CONCLUSIONS@#FTIR technique has the potential to diagnose acute and old myocardial infarction, and provides a new basis for the analysis of the causes of sudden cardiac death.

Identification of the New Psychoactive Substance Eutylone / 法医学杂志

OBJECTIVES@#To establish a method to identify unknown sample based on the combined use of Fourier transform infrared spectroscopy (FTIR), gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry (UPLC-LTQ-Orbitrap MS) and 1H-nuclear magnetic resonance spectroscopy (1H-NMR) technique.@*METHODS@#The unknown sample was directly analyzed by FTIR. The unknown sample was dissolved in methanol solution containing internal standard SKF525A and the supernatant was detected by GC-QTOF-MS and UPLC-LTQ-Orbitrap MS. The unknown sample was dissolved in methanol-d4 solution for structural analysis of 1H-NMR.@*RESULTS@#The characteristic absorption peaks of FTIR spectra obtained from unknown sample were 1 682 (C=O bond), 1 503, 1 488, 1 436, 1 363, 1 256, 1 092, 1 035, 935, 840 and 800 cm-1, the characteristic fragment ions (m/z) of GC-QTOF-MS were 86.096 4 (base peak), 58.065 1, 149.023 5, 121.028 6 and 65.038 6, the accurate mass [M+H]+ detected by UPLC-LTQ-Orbitrap MS was 236.127 7. The sample was identified as synthetic cathinone new psychoactive substance Eutylone by 1H-NMR.@*CONCLUSIONS@#The method established in this study can be used for structural confirmation of Eutylone.

Chemical pattern recognition of YuanZhi San capsule based on FTIR and HPLC analysis / 国际药学研究杂志

Objective: To provide a scientific basis for the quality control of YuanZhi San capsule(YZSC). Methods: Fourier transform infrared spectroscopy(FTIR)combined with second derivative spectra was used to analyze the chemical components of YZSC;high performance liquid chromatography(HPLC)was used to establish the fingerprints of different batches of YZSC, the quality assessment of YZSC was carried out by similarity evaluation, cluster analysis(CA), principal component analysis(PCA)and orthogonal partial least squares discriminant analysis(OPLS-DA). Results: The main components of YZSC were carbohydrate, flavonoids, alkaloids, organic acids and saponins. There were 41 common peaks in the fingerprint, seven peaks were identified using reference substance, they were 3, 6'-disinapoylsucrose, ferulic acid, jatrorrhizine hydrochloride, palmatine chloride, berberine, quercetin and β-asarone. The similarity of 10 batches of samples was higher than 0.99. The CA and PCA analysis indicated that there were differences in different batches of YZSC, and they were mainly divided into two categories. By the OPLS-DA, 10 main chemical constituents were found to be the cause of the quality differences in the batches, and the peaks of berberine, 3, 6'-disinapoylsucrose, palmatine chloride, β-asarone, and jatrorrhizine hydrochloride were recognized by comparison with the reference substances. Conclusion: The chemical pattern recognition technology based on the FTIR and HPLC analysis might be used for the quality evaluation of YZSC.

The effect of light sources and CAD/CAM monolithic blocks on degree of conversion of cement

PURPOSE: To assess the degree of conversion (DC) and light irradiance delivered to light-cured and dual-cured cements by application of different light sources through various types of monolithic computer-aided design and computer-aided manufacturing (CAD/CAM) materials. MATERIALS AND METHODS: RelyX Ultimate Clicker light-cured and dual-cured resin cement specimens with 1.5-mm thicknesses (n=300, 10/group), were placed under four types of crystalline core structure (Vita Enamic, Vita Suprinity, GC Ceresmart, Degudent Prettau Anterior). The specimens were irradiated for 40 seconds with an LED Soft-Start or pulse-delay unit or 20 seconds with a QTH unit. DC ratios were determined by using Fourier transform infrared spectroscopy (FTIR) after curing the specimen at 1 day and 1 month. The data were analyzed using the Mann-Whitney U test (for paired comparison) and the Kruskal-Wallis H test (for multiple comparison), with a significance level of P < .05. RESULTS: DC values were the highest for RelyX Ultimate Clicker light-cure specimens polymerized with the LED Soft-Start unit. The combination of the Vita Suprinity disc and RelyX Ultimate Clicker dual-cure resin cement yielded significantly higher values at both timepoints with all light units (all, P < .05). CONCLUSION: Within the limitations of this study, we conclude that the DC of RelyX Ultimate Clicker dual-cure resin cement was improved significantly by the use of Vita Suprinity and the LED Soft-Start light unit. We strongly recommend the combined use of an LED light unit and dual-cure luting cement for monolithic ceramic restorations.

ldentification of Viola yedoensis Makino and Viola inconspicua by FT-l R / 中国药科大学学报

The different extracts and of Viola yedoensis Makino and Viola inconspicua were analyzed and identi-fied by Fourier transform infrared spectroscopy (FT-IR). One-dimensional infrared spectrum showed that the extracts of Viola yedoensis Makino and Viola inconspicua contained the aromatics,volatile substances and glyco-sides,with not significant differences from each other. However,different extraction sites of the two medicinal materials in second derivation spectrum were obviously different,especially the number of automatic peaks and peak intensity in the range of 970 800 cm-1. Viola yedoensis Makino displayed 5 automatic peaks,6 automatic peaks and 6 automatic peaks,while Viola inconspicua displayed 7 automatic peaks,4 peaks,4 peaks in the second derivation spectrum of petroleum ether extraction site,chloroform extraction site and the ethyl acetate extraction site. In addition,the peak position of the strongest peak in the second derivative of the ethyl acetate extraction site was 1 467 cm-1,while the strongest peak of the Viola inconspicua was at 1 384 cm-1,so the two medicinal mate-rials can be distinguished by the strongest peak position of ethyl acetate extraction site in second derivation spec-trum. Studies demonstrated that one-dimensional infrared spectroscopy combined with the second-order derivative analysis could achieve the accurate identification between Viola yedoensis Makino and Viola inconspicua. This research provides new ideas and new methods for the identification of Viola and other adulterants.