Fourier Transform Infrared (FTIR) Spectroscopic Analyses of Microbiological Samples and Biogenic Selenium Nanoparticles of Microbial Origin: Sample Preparation Effects

To demonstrate the importance of sample preparation used in Fourier transform infrared (FTIR) spectroscopy of microbiological materials, bacterial biomass samples with and without grinding and after different drying periods (1.5–23 h at 45 °C), as well as biogenic selenium nanoparticles (SeNPs; without washing and after one to three washing steps) were comparatively studied by transmission FTIR spectroscopy. For preparing bacterial biomass samples, Azospirillum brasilense Sp7 and A. baldaniorum Sp245 (earlier known as A. brasilense Sp245) were used. The SeNPs were obtained using A. brasilense Sp7 incubated with selenite. Grinding of the biomass samples was shown to result in slight downshifting of the bands related to cellular poly-3-hydroxybutyrate (PHB) present in the samples in small amounts (under ~10%), reflecting its partial crystallisation. Drying for 23 h was shown to give more reproducible FTIR spectra of bacterial samples. SeNPs were shown to contain capping layers of proteins, polysaccharides and lipids. The as-prepared SeNPs contained significant amounts of carboxylated components in their bioorganic capping, which appeared to be weakly bound and were largely removed after washing. Spectroscopic characteristics and changes induced by various sample preparation steps are discussed with regard to optimising sample treatment procedures for FTIR spectroscopic analyses of microbiological specimens

Fourier Transform Infrared (FTIR) Spectroscopic Study of Biofilms Formed by the Rhizobacterium <i>Azospirillum baldaniorum</i> Sp245: Aspects of Methodology and Matrix Composition

Biofilms represent the main mode of existence of bacteria and play very significant roles in many industrial, medical and agricultural fields. Analysis of biofilms is a challenging task owing to their sophisticated composition, heterogeneity and variability. In this study, biofilms formed by the rhizobacterium Azospirillum baldaniorum (strain Sp245), isolated biofilm matrix and its macrocomponents have for the first time been studied in detail, using Fourier transform infrared (FTIR) spectroscopy, with a special emphasis on the methodology. The accompanying novel data of comparative chemical analyses of the biofilm matrix, its fractions and lipopolysaccharide isolated from the outer membrane of the cells of this strain, as well as their electrophoretic analyses (SDS-PAGE) have been found to be in good agreement with the FTIR spectroscopic results

Психологические маркеры созависимого поведения: теория и практика

Introduction. The purpose of the article is an analytical review of scientific approaches to thestudy of the features of psychological markers of codependent behavior. Modern approachesto the study of this phenomenon from the point of view of theoretical and practical aspects,reflecting the fragmentary nature of the representation of this concept, are considered. Thereare not only several definitions of the concept of "codependency", but also many approachesto its study. Based on the theoretical analysis of various approaches, the author\u27s definition ofthe phenomenon was proposed, which reflects the scientific novelty of the study. The theoreticaljustification of the problem under study was carried out on the basis of the analysis of literarysources, comparative analysis and generalization of foreign and domestic approaches to theterm "codependency" under study, approbation of the author\u27s interpretation of the term understudy. Results. Based on the analytical review, psychological markers of codependent behaviorare identified, manifested through a learned set of behavioral forms, adaptation disorders, andvarious personality disorders. It is shown that the description of psychological characteristics relatedto the phenomenon of codependency is quite extensive, but it is not systemic. The ideas areoutlined not only to continue the study of psychological markers of codependent behavior, butalso to search for genetic factors that cause this behavior. Discussion. We have identified theinterpretation of the term "codependency" as a phenomenon manifested in dependent behaviorcaused by a change in value-semantic constructs and a lack of necessary competencies, formedunder the influence of negative experience of dysfunctional relationships with significant others.This definition combines a number of approaches and enriches them with a look through theprism of the deep features of a person who exhibits codependent patterns of behavior.Введение. Целью статьи является аналитический обзор научных подходов к исследованию особенностей психологических маркеров созависимого поведения. Рассмотрены современные подходы к изучению данного феномена с точки зрения теоретического и практического аспектов, отражающие фрагментарный характер представленности данного понятия. Существует не только несколько дефиниций понятия «созависимость», но и множество подходов к его изучению. На основе теоретического анализа различных подходов было предложено авторское определение феномена, что отражает научную новизну исследования. Теоретическое обоснование исследуемой проблематики было выполнено на основе анализа литературных источников, сравнительного анализа и обобщения зарубежных и отечественных подходов к изучаемому термину «созависимость», апробации авторской трактовки исследуемого термина. Результаты. На основе аналитического обзора выделены психологические маркеры созависимого поведения, проявляющиеся через выученный набор поведенческих форм, нарушение адаптации, различные нарушения личности. Показано, что описание психологических характеристик, относящихся к феномену созависимости, достаточно обширно, но при этом не носит системный характер. Намечены идеи не только для продолжения изучения психологических маркеров созависимого поведения, но и для поиска генетических факторов, обуславливающих данное поведение. Обсуждение результатов. Нами выделена трактовка термина «созависимость» как феномена, проявляющегося в зависимом поведении, обусловленного изменением ценностно-смысловых конструктов и недостатком необходимых компетенций, формирующегося под влиянием негативного опыта дисфункциональных отношений со значимыми другими. Данное определение объединяет ряд подходов и обогащает их взглядом сквозь призму глубинных особенностей личности, проявляющей созависимые паттерны поведения

Role of vitamin D in pre-school children’s health

Vitamin D has pleiotropic effects, including maintaining calcium and phosphate homeostasis, and affecting the immune and endocrine systems. The article summarizes data on the expected biological effects of vitamin D on children’s health. The results of randomized clinical trials evaluating the effect of vitamin D supplementation on the incidence of acute respiratory tract infections are reviewed in detail. It has been shown that daily intake of vitamin D at a dose of 10 to 25 mcg/day (400–1000 IU/day) compared with placebo leads to a significant decrease in the proportion of children and adolescents who have had at least one episode of acute respiratory infection. The criteria for the provision of calciferol and the gradation of the status of vitamin D deficiency and deficiency in different countries are discussed. It has been shown that in the interpretation of the 25 (OH) D results there is a consensus on two points: calcidiol levels below 12 ng/ml (30 nmol/L) are considered clearly insufficient, and levels above 30 ng/ml (75 nmol/L) are considered sufficient in all regions. The incidence of hypovitaminosis D has been reported in children aged 3 to 7 years, where the overall combined assessment, regardless of age group, ethnic composition and breadth of the studied populations, showed that 13% of European children had a serum calcidiol concentration of less than 12 ng/ml (&lt;30 nmol/L), and about 40% had a level of less than 30 ng/ml (&lt;75 nmol/L). The data on the physiological need and the recommended daily dose of vitamin D for preschool children have been analyzed. In each country, the recommended intake of vitamin D is set (from 400 to 4000 IU), depending on the target concentration of serum calcidiol, the level of insolation, and nutritional characteristics. The necessity of conducting clinical studies in the age group from 3 to 7 years to determine an adequate, effective and safe preventive dose of vitamin D for preschool children in the Russian Federation is emphasized