Kristina R. Popova

In Russia, viral agents dominate the etiological structure of аcute intestinal infections (AII), with rotavirus and norovirus playing the major role. Vaccination against rotavirus infection (RVI) demonstrates high efficacy (78—94%) in preventing severe forms requiring hospitalization. The introduction of rotavirus vaccination has altered the etiological landscape; however, the clinical features of AII in vaccinated children, including breakthrough infections and coinfections, remain insufficiently studied. Objective : to analyze the course of acute intestinal infections (AII) in unvaccinated and rotavirus-vaccinated children aged 8 months to 3 years. Materials and methods . A prospective observational cohort study was conducted at the G.N. Speransky Children's City Clinical Hospital (Moscow) in 2023—2024. The study included 205 patients hospitalized with AII within the first three days of symptom onset. Two groups were formed: children vaccinated against RVI (n = 93) and unvaccinated children (n = 112). Etiological diagnosis was performed by PCR; rotavirus genotyping was carried out (Sanger sequencing). Statistical analysis included the Mann—Whitney U test, Pearson's chi-squared test, calculation of odds ratios (OR) and 95% confidence intervals (CI). Results. The groups were comparable in sex, age, and time of hospitalization (median — second day of illness). Vaccinated patients had a significantly shorter duration of illness: median 5 days [4;5] versus a longer course in the unvaccinated group (p = 0.033). The frequency of gastroenteritis in the vaccinated group was almost twofold lower — 29.0% (95% CI: 20.4—38.6%) compared to 56.6% (95% CI: 46.7—65.3%) in the comparison group (p = 0.001). Rotavirus was detected significantly less often in vaccinated children: 10/93 (10.8%) versus 41/109 (37.6%) in unvaccinated children (χ² = 17.79; p < 0.0001; OR = 0.200; 95% CI: 0.093—0.428). The detection rate of norovirus did not differ between the groups (30.1% vs 20.2%; p = 0.143). Campylobacter was detected more frequently in vaccinated children: 12/93 (12.9%) versus 4/109 (3.7%) (p = 0.031; OR = 3.89; 95% CI: 1.21—12.51); however, the authors note the possibility of Berkson's bias due to the small number of cases. Among vaccinated children with confirmed rotavirus infection (n = 10), hyperthermia above 39°C was not recorded (0%), whereas in the unvaccinated group (n = 42) this symptom was observed in 31% (95% CI: 16.7—45.0%). The predominant rotavirus genotype in both groups was G3[P8].

Introduction. Salmonella Kentucky sequence type ST198 is one of the epidemiologically significant non-typhoidal Salmonella clones worldwide and is characterized by the presence of highly resistant strains and the ability to adapt to different animal hosts and environmental conditions. The aim of this study was to analyze S. Kentucky strains isolated from various sources in Russia in terms of their phylogenetic position within the global diversity of the pathogen and their genetic characteristics. Materials and methods. We examined 55 strains of S. Kentucky by whole-genome sequencing, which were isolated from 2010 to 2022 from various sources (clinical strains, food, as well as from farm animals, feed and environmental samples). Whole genome sequencing was performed using Illumina platforms. Phylogenetic analysis based on nucleotide variation analysis included an additional 390 S. Kentucky strains. Results. Most of the Russian strains (n = 50) belonged to the ST198 sequence type, four strains were ST314 and one strain was ST152. Of the 50 Russian sequence-type ST198 strains, 44 belonged to the international monophyletic MDR lineage S. Kentucky ST198, and belonged to four separate sublineages, six strains occupying a basal position in relation to the MDR lineage. A total of 320 genes and mutations responsible for resistance to antimicrobial agents were identified. The most common were point mutations in the QRDR region. In most cases, Russian strains were characterized by the presence of variants of the SGI1-K genomic island. Moreover, the putative structure of SGI1 was correlated with the phylogenetic clustering of S. Kentucky sublineages. Conclusions. The results of the study made it possible to assess the population structure of Russian S. Kentucky ST198 strains on a global scale and determine the genetic determinants of antibiotic resistance, including the structure of the SGI1 genomic island.

В статье изучено влияние стероидных фитогормонов – брассинолидов на морфогенетические особенности регенерантов некоторых древесно-кустарниковых видов в культуре in vitro. Эпибрассинолид в составе препарата «Эпин-Экстра» оказывает стимулирующее действие на развитие растений. Поэтому добавление данного препарата в питательную среду должно усиливать действие цитокининов и, как следствие, оказывать положительный эффект на ростовые показатели растений-регенерантов. Полученные результаты свидетельствуют об эффективности внесения в питательные среды для древесных культур эпибрассинолида на этапе микроклонального размножения. Ответные реакции исследуемых объектов: Robinia pseudoacacia L., Cotinus coggygria Scop., подвой Cerasus носят индивидуальный характер и зависят от конкретного генотипа. В качестве эксплантов использовали микрочеренки с одной парой пазушных почек. Культивирование проводили на питательных средах с основным составом макро- и микроэлементов по протоколу Мурасиге и Скуга. В качестве основного цитокинина использовали 6-бензилоаминопурин. Растения культивировали на фитостеллажах при 16-ти часовом фотопериоде и температуре 22-24°C. В течение эксперимента фиксировали линейный прирост, коэффициент размножения, а также общее влияние брассиностероидов на развитие растений в культуре in vitro. Добавление в питательную среду эпибрассинолида для размножения в культуре in vitro древесно-кустарниковых видов экономически выгодно и значительно сокращает сроки культивирования и получения максимального коэффициента размножения. The article studies the effect of steroid phytohormones – brassinolides on the morphogenetic features of some tree and shrub species regenerants in “in vitro” culture. Epibrassinolide in the preparation “Epin-Extra” has a stimulating effect on the plants development. Therefore, the addition of this preparation to the nutrient medium should enhance the effect of cytokinins and, as a result, have a positive effect on the growth indicators of regenerating plants. The results obtained indicate the effectiveness of the epibrassinolide introduction into the nutrient medium for tree crops at the stage of microclonal reproduction. The responses of the studied objects: Robinia pseudoacacia L., Cotinus coggygria Scop., Cerasus rootstock are individual and depend on a specific genotype. Micro-rootstocks with one pair of axillary bud were used as explants. Cultivation was carried out on nutrient medium with the basic composition of macro- and microelements according to the Murashige and Skuga protocol. 6-benzyloaminopurine was used as the main cytokinin. The plants were cultivated on phytostellages at a 16-hour photoperiod and a temperature of 22-24°C. During the experiment, linear growth, reproduction coefficient, as well as the total effect of brassinosteroids on the plants development in culture “in vitro” were determined. The addition of epibrassinolide to the nutrient medium for reproduction in “in vitro” culture of tree and shrub species is economically advantageous and significantly reduces the time of cultivation and obtaining the maximum reproduction coefficient.

Картофель называют вторым хлебом, так как он является наиболее распространенной и ценной, после зерновых, культурой. В процессе хранения, наряду с товарным видом, клубни теряют свои вкусовые качества и полезные вещества. В среднем 2/3 потери массы картофеля приходится на испарение воды и 1/3 на расходование органических веществ при дыхании. Существуют различные способы уменьшения потерь при длительном хранении картофеля, включающие соблюдение температурного режима, определенной влажности воздуха и степени освещенности помещения. А также дополнительную обработку клубней при загрузке в хранилище биологическими и химическими защитно-стимулирующими средствами и ингибиторами прорастания. В промышленности чаще всего используют обработку картофеля этиленом, ХИПК или похожими ингибиторами химического происхождения с целью экономической выходы. Однако применение в этих целях эфирных масел не уступает по эффективности и позволяет получить более экологически чистую продукцию. В статье приведен обзор различных способов хранения картофеля, с упором на использование эфирных масел, обеспечивающих поддержание его товарного вида и уровня полезных веществ. Среди перспективных и набирающих популярность способов можно выделить периодическую обработку клубней картофеля эфирными маслами семейства Umbellíferae, Rutaceae и Lamiaceae.