Thanatochemistry at the crime scene: a microfluidic paper-based device for ammonium analysis in the vitreous humor
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20.11.2019 |
Musile G.
Agard Y.
De Palo E.
Shestakova K.
Bortolotti F.
Tagliaro F.
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Analytica Chimica Acta |
10.1016/j.aca.2019.07.033 |
0 |
Ссылка
© 2019 Elsevier B.V. Most of the on-site approaches for inferring of the post-mortem interval are still based on observative data from the direct body inspection, whereas, objective and quantitative analyses, such as potassium in the vitreous humor, are require laboratory instrumentation and skilled personnel. The present paper presents a simple and low cost analytical method suitable for use at the crime scene for inferring the time since death. The method uses a microfluidic paper-based device (μPAD) for the determination of ammonium in the vitreous humor (VH) based on the selective interaction between the ammonium and the Nessler's reagent. The color change was measured in terms of “RGB distance” by using a simple and free smartphone application. The optimized device showed a limit of detection of 0.4 mmol L−1, with between days precision less than 9.3% expressed as relative standard deviation, and accuracy between days from 94.5% to 104.5%. The selectivity of the Nessler's reaction was tested towards the main vitreous humor compounds, and no significant interferences were found. This paper-based analytical device was successfully used for the determination of ammonium ion in VH samples from forensic autopsies. The results obtained with the proposed method, although for a limited number of cases (n = 25), showed a close correlation with the data obtained with an instrumental analysis based on capillary electrophoresis. Moreover, in order to make the evaluation of results as simple as possible, a direct correlation between the color intensity, expressed as RGB distance, and the post-mortem interval was studied and a significant correlation was found (R2 > 0.78). In conclusion, the present preliminary study showes that the proposed device could be an additional tool to the traditional methods for a more accurate, although still presumptive, estimation of the time of death directly at the crime scene.
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Synthesis, antibacterial and antitumor activity of methylpyridinium salts of pyridoxine functionalized 2-amino-6-sulfanylpyridine-3,5-dicarbonitriles
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02.09.2018 |
Grigor’ev A.
Shtyrlin N.
Gabbasova R.
Zeldi M.
Yu. Grishaev D.
Gnezdilov O.
Balakin K.
Nasakin O.
Shtyrlin Y.
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Synthetic Communications |
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3 |
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© 2018, © 2018 Taylor & Francis. A library of 29 2-amino-6-sulfanylpyridine-3,5-dicarbonitriles functionalized with a pyridoxine moiety was synthesized using a three-component one-pot reaction of aldehyde derivative of pyridoxine, malononitrile, and thiophenol. The obtained bipyridine structures were converted into methylpyridinium salts. Several compounds demonstrated expressed antibacterial activity with MICs (minimum inhibitory concentrations) in the range of 0.5–4 µg/mL against the three studied Gram-positive strains and 8–64 µg/mL against the Gram-negative E. coli strain, which was comparable or better than the activity of the reference antimicrobial agents. At the same time, all the synthesized compounds were inactive against the Gram-negative P. aeruginosa. Several compounds also demonstrated high cytotoxic activity against the studied tumor cells, but without selectivity for the normal HSF (human foreskin fibroblast) cells. Despite the preliminary character of the performed biological studies, the obtained results make the obtained structural chemotype a promising starting point for the design of physiologically active compounds.
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Comparative effectiveness of vitamin-mineral complexes with iron in correcting iron deficiency in women in the outpatient setting
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01.01.2018 |
Svistunov A.
Osadchuk M.
Kireeva N.
Lazareva A.
Shorina D.
Vasil'eva I.
Savina T.
Tuaeva E.
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Terapevticheskii Arkhiv |
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© 2018 Media Sphera Publishing Group. All rights reserved. Àim. To compare the efficacy of prophylactic administration of mineral-vitamin complexes "Feroglobin-B12" and "Complivit iron" with different degrees of Fe valence. Materials and methods. 120 female subjects were examined. To determine the quality of life, the SF-36 questionnaire was used. The presence of anxiety was determined on the Spielberger-Khanin Alarm Scale. 30 women with a deficit of Fe were divided into 2 groups of 15 people each. The first group received "Ferroglobin-B12", the second – "Complivit iron" for a month. Results. In a month after the initiation of preventive therapy in women of the 1 group the content of Fe serum was normalized. In the second group, its concentration approached the control values. The difference in Fe content in the 1 and 2 groups was of a reliable nature. Conclusion. The intake of "Ferroglobin-B12" was not accompanied by side effects, and performance indicators, social activity and mental health reached control values, unlike the group of patients taking Complivit iron.
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