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For the first time we used CuAAC click reaction for the synthesis of cyanine labeled qPCR probes. We performed the comparison of dyes and quenchers (Cy5 vs disulfo-Cy5 and BHQ2 vs BHQ3) in several TaqMan probes with different stability of the secondary structure. Based on the studies of thermal quenching of dyes, increase of fluorescence during probe melting and in the course of qPCR, we suggest that disulfo-Cy5-BHQ2 pair is a preferable one for molecular beacons due to the highest increase of fluorescence during melting. As Cy5-BHQ3 pair gave better Cq and maximal relative increase of fluorescence in qPCR in comparison to others we recommend this pair for Taqman style probe design.

An alkyl azide derivative of 1-phenylethynylpyrene (PEPy) dye was prepared and used in the functionalization of oligonucleotides via click chemistry. Spectral and photo-physical properties of the PEPy-modified oligonucleotides as a single strand, and in perfect or mismatched duplexes, have been studied. A series of PEPy-Dabcyl fluorogenic TaqMan probes were synthesized and tested in qPCR. PEPy proved to be a superior substitute for AMCA as a short wavelength fluorescent dye for qPCR probes. PEPy probes were shown to significantly reduce Cq (a fractional PCR cycle used for quantification) vs. AMCA labeled probes, thus improving on the reliability of detection. Moreover, a larger increase of fluorescence during amplification was observed in the case of PEPy probes that makes this dye very suitable for an end-point PCR technique. This study broadens the panel of fluorescent dyes suitable for the use in probes for quantitative real-time PCR.

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The kinetics of scandium sorption with impregnate-containing extractant – phosphine oxide based on hypercrosslinked polystyrene from nitric acid solutions was studied using a method of limited solution volume. A sample of sorbent obtained by impregnation contained 0.233 g extractant/g impregnate. Under batch conditions, the influence of temperature in the range 293-313 K on the kinetics of scandium sorption by impregnate was studied. It was revealed that the saturation of impregnate by scandium is established in 20-30 min. For the processing of integral kinetic scandium sorption curves, the pseudo-first and pseudo-second-order models, as well as the Elovich equation, were used. The values of the rate constants calculated from the pseudo-second-order model, describing the kinetic data with the best correlation coefficients (R2 0.931-0.995), reach (9.51-10.4) g∙(mmol∙min)-1. The activation energy of scandium sorption, calculated by an equation similar to the Arrhenius equation, is (2.8±0.2) kJ / mol. Due to the improved kinetic characteristics compared with traditional sorbents, hypercrosslinked polystyrene impregnates containing phosphine oxide can be used to extract of scandium from solutions formed during the processing of scandium-containing raw materials.Forcitation:Pyae Phyo Aung, Veselova O.A., Troshkina I.D. Kinetics of scandium sorption by impregnate containing phosphinoxide. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 8. P. 28-30.

Rotavirus infection is one of the primary causes of acute gastroenteritis in industrialized countries and may be a cause of severe disease in children. Here we present the results of analysis of specific indicators which characterize the burden of rotavirus infection in Russia such as passive surveillance data for rotavirus gastroenteritis cases (RG), the proportion of outbreaks of rotavirus per calendar month and laboratory-based data of rotavirus infection occurrence in lethal cases involving children. Specific features of rotavirus [P]G genotypes distribution in different geographic regions of Russia from 2012 through 2013 are also provided.

Infectious diarrhea is one of the leading causes of fatal outcomes in young children. Differential diagnostics of such infections within the first hours of illness poses significant objective obstacles. Data from laboratory studies of autopsy material and pathological studies provide valuable information for understanding the spectrum of differential diagnostics and etiological structure of infectious diarrhea with fatal outcomes in young children. Materials and methods. There were analyzed 100 cases of fatal outcomes in children under the age of six years registered in Russia from November 2011 to December 2019, who was diagnosed with infectious diarrhea at different levels of the healthcare system. The data were assessed based on available medical case reports and the laboratory testing of autopsy samples performed by using nucleic acid amplification methods. Results. The diagnosis of infectious diarrhea was revised in 24 patients, based on the data of a set of intravital and post-mortem studies. In patients with unconfirmed diagnosis of acute intestinal infections, pneumonia was the most often detected — in 45.8% (11/24), sepsis — in 29.2% (7/24), meningitis/meningoencephalitis, acute surgical pathology and asphyxiation associated with vomit aspiration — in 16.7 % (4/24) cases. The causative agents of infectious diarrhea were identified in 71 of 76 patients with confirmed diagnosis of acute intestinal infections. Most prevalent were group A rotaviruses — 52.6% (40/76), group F adenoviruses — 17.1% (13/76), and noroviruses — 13.2% (10/76). Combination of pathogens was detected in 29 cases (38.2%). Prehospital lethal outcomes in patients with infectious diarrhea were observed in 17 cases (22.4%). In total, rate of neonatal deaths due to acute intestinal infections accounted for 62.2% and 2-year-old toddlers — 20.3%. 64 of 76 (84%) children had no unfavorable premorbid background. The most common pathologies associated with infectious diarrhea with developing fatal outcomes were pneumonia (including aspiration pneumonia) in 22.4% (17/76) and aspiration asphyxia in 6.6% (5/76). Hemolytic-uremic syndrome associated with diarrhea was diagnosed in 7.9% (6/76) of children. Conclusions. Within the first years of life children comprise a risk group for developing fatal outcomes during infectious diarrhea. Lack of unfavorable premorbid background should not be considered as a reliable positive prognostic criterion. Diagnostics of pneumonia should be included in the mandatory examination plan for children with severe infectious diar rhea. Based on study of clinical and autopsy material, group A rotaviruses were the lead causative agents among those resulting in infectious diarrhea with fatal outcomes in young children. Special attention should be paid to preventing vomit aspiration within the first days after disease onset.