Mesenchymal stem cells lose the senescent phenotype under 3D cultivation

BACKGROUND

Three-dimensional (3D) cell culture is widely used in various fields of cell biology. In comparison to conventional two-dimensional (2D) cell culture, 3D cell culture facilitates a more accurate replication of the in vivo microenvironment, which is essential for obtaining more relevant results. The application of 3D cell culture techniques in regenerative medicine, particularly in mesenchymal stem cell (MSC)-based research, has been extensively studied. Many of these studies focus on the enhanced paracrine activity of MSCs cultured in 3D environments. However, few focus on the cellular processes that occur during 3D cultivation.

METHODS

In this work, we studied the changes occurring within 3D-cultured MSCs (3D-MSCs). Specifically, we examined the expression of numerous senescent-associated markers, the actin cytoskeleton structure, the architecture of the Golgi apparatus and the localization of mTOR, one of the main positive regulators of replicative senescence. In addition, we assessed whether the selective elimination of senescent cells occurs upon 3D culturing by using cell sorting based on autofluorescence.

RESULTS

Our findings indicate that 3D-MSCs were able to lose replicative senescence markers under 3D cell culture conditions. We observed changes in actin cytoskeleton structure, Golgi apparatus architecture and revealed that 3D cultivation leads to the nuclear localization of mTOR, resulting in a decrease in its active cytoplasmic form. Additionally, our findings provide evidence that 3D cell culture promotes the phenotypic reversion of senescent cell phenotype rather than their removal from the bulk population.

CONCLUSION

These novel insights into the biology of 3D-MSCs can be applied to research in regenerative medicine to overcome replicative senescence and MSC heterogeneity as they often pose significant concerns regarding safety and effectiveness for therapeutic purposes.

Disruption of the pro-inflammatory, anti-inflammatory cytokines and tight junction proteins expression, associated with changes of the composition of the gut microbiota in patients with irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is a pathologic condition characterized by changes in gut microbiome composition, low-grade inflammation, and disruption of intestinal wall permeability. The interaction between the gut microbiome and the disease manifestation remains unclear. The changing of tight junction proteins and cytokines expression throughout the gastrointestinal tract in IBS patients has not been studied yet.

AIM OF THE STUDY

To assess the changes of gut microbiome composition, tight junction proteins, and cytokines expression of intestinal mucosa from the duodenum to the distal part of the colon in IBS patients and healthy volunteers.

METHODS

In 31 IBS patients (16 patients with IBS-D; 15 patients with IBS-C) and 10 healthy volunteers the expression of CLD-2, CLD-3, CLD-5, IL-2, IL-10, and TNF-α in mucosal biopsy specimens was determined by morphological and immune-histochemical methods. The qualitative and quantitative composition of the intestinal microbiota was assessed based on 16S rRNA gene sequencing in both groups of patients.

RESULTS

The expression of IL-2 and TNF-α was significantly increased in IBS patients compared with the controls (p<0.001), with a gradual increase from the duodenum to the sigmoid colon. The expression of IL-10, CLD-3, and CLD-5 in mucosal biopsy specimens of these patients was lower than in the control group (p<0.001). Increased ratios of Bacteroidetes and decreased ratios of Firmicutes were noted in IBS patients compared to healthy volunteers (p<0.05).

CONCLUSION

IBS patients have impaired gut permeability and persisting low-grade inflammation throughout the gastrointestinal tract. Changes in the gut microbiota may support or exacerbate these changes.

Dragendorff's reagent: Historical perspectives and current status of a versatile reagent introduced over 150 years ago at the University of Dorpat, Tartu, Estonia

The well-known Dragendorff's reagent (DR) was introduced by an Estonian-German Professor Johann Georg Noel Dragendorff (1836-1898) in the middle of the 19th century (1866). Dragendorff, who was a full-time professor in pharmacy at the university of Dorpat (Tartu) used his reagent originally for the rapid screening of herbal products to find traces of alkaloids. DR is a solution of potassium bismuth iodide composing of basic bismuth nitrate (Bi(NO₃)₃), tartaric acid, and potassium iodide (KI), and when contact with alkaloids DR produces an orange or orange red precipitate. In this review article, we make a short historical overview on the biography and scientific research work of Professor Dragendorff at the University of Dorpat. The chemistry, method of preparation, mechanism of action, and practical uses of DR in various disciplines in various European countries including the Baltic countries (Estonia, Latvia, Lithuania), Finland, Ukraine, Moldova, and in Asia (Vietnam), are also discussed. Over several decades, DR and its modifications have found uses in many new applications and disciplines, and a number of commercial DRs are also currently available on the market. Today, DR is used for example in the production of surfactants, where non-ionic surfactant is precipitated in water solution with modified DR (KBiI₄+BaCl₂+glacial acetic acid). Total six different potassium iodobismuthate (DR) solutions are also presented in the European Pharmacopoeia. In conclusion, DR (after more than 150 years of its invention in Estonia) has still an important role in pharmaceutical and related sciences all over the world.

PSYCHOPHYSIOLOGICAL INDICATORS OF FLOW STATE

Aim. The study aims to reveal objective psychophysiological indicators that are related to flow state. Materials and methods. Thirty-one (31) athletes of different competitive levels (20 females and 11 males, mean age 19.1 ± 4.59 years) participated in the study. The dynavision D2 training device was applied for creating optimal flow state conditions during the experiment. Physiological indicators were recorded by the Thought Technology hardware and software system. Heart rate variability, respiration rate (thoracic and abdominal), finger temperature, skin conductance were analyzed. Flow state depth was estimated based on the participants’ answers during the semi-structured interview that followed the experiment. Results. According to the results of the interview, all athletes were divided into two groups: the first group included athletes experiencing flow state (“flow” group), the second group composed of athletes who did not manage to experience flow state (“no-flow” group). When comparing these two groups after the experiment, it was revealed that the first group had higher levels of standard deviations of heart rate compared with the second group. In the first group (flow), the following indicators were significantly higher after the experiment: standard deviation of the RR-intervals (SDRR), skin conductance, and finger temperature. In the second group (no-flow), only skin conductance increased significantly. Conclusion. The results allow us to conclude that the flow state is characterized by a marked increase in the sympathetic nervous system (a higher level of stress compared to the same activity without flow). 

Control of autoresonance in mechanical and physical models

Autoresonant energy transfer has been considered as one of the most effective methods of excitation and control of high-energy oscillations for a broad range of physical and engineering systems. Nonlinear time-invariant feedback control provides effective self-tuning and self-adaptation mechanisms targeted at preserving resonance oscillations under variations of the system parameters but its implementation may become extremely complicated. A large class of systems can avoid nonlinear feedback, still producing the required state due to time-variant feed-forward frequency control. This type of control in oscillator arrays employs an intrinsic property of a nonlinear oscillator to vary both its amplitude and the frequency when the driving frequency changes. This paper presents a survey of recently published and new results studying possibilities and limitations of time-variant frequency control in nonlinear oscillator arrays.This article is part of the themed issue 'Horizons of cybernetical physics'.

The Home Representation Impact on the Adopted Adolescents’ Adaptation to the Foster Families

Home representations in the adaptation of adopted adolescents to the foster families were investigated. 30 parents (5 fathers and 25 mothers, age from 35 to 45) and 30 adolescents (11 girls and 19 boys, age from 14 to 15) participated in the study. The independent variable was home representation, the dependent one – home attachment and family attachment as markers of adolescents’ adaptation to home. The following tools were used: the Functionality of the Home Environment Questionnaire (Nartova-Bochaver et al., 2015), the Relevance of the Home Environment Questionnaire (Nartova-Bochaver et al., 2016), Home Attachment Scale (Reznichenko et al., 2016), and Family Allоcentrism Scale scores (Lay et al., 1998). There was revealed that Functionality, Relevance, and Family Allоcentrism Scale were higher in parents than in children whereas Home Attachment scores weren’t. It was shown as well that similarity of the home representations in children and parents impacted on the family attachment but not home attachment. The Relevance of the Home Environment was stronger predictor of the children’s family attachment than Functionality. The applications of the study seem to be helpful in the practical work with foster families and children which could intensify home personalization techniques in children.

Cross-Cultural Differences in a Global “Survey of World Views”

We know that there are cross-cultural differences in psychological variables, such as individualism/collectivism. But it has not been clear which of these variables show relatively the greatest differences. The Survey of World Views project operated from the premise that such issues are best addressed in a diverse sampling of countries representing a majority of the world’s population, with a very large range of item-content. Data were collected online from 8,883 individuals (almost entirely college students based on local publicizing efforts) in 33 countries that constitute more than two third of the world’s population, using items drawn from measures of nearly 50 variables. This report focuses on the broadest patterns evident in item data. The largest differences were not in those contents most frequently emphasized in cross-cultural psychology (e.g., values, social axioms, cultural tightness), but instead in contents involving religion, regularity-norm behaviors, family roles and living arrangements, and ethnonationalism. Content not often studied cross-culturally (e.g., materialism, Machiavellianism, isms dimensions, moral foundations) demonstrated moderate-magnitude differences. Further studies are needed to refine such conclusions, but indications are that cross-cultural psychology may benefit from casting a wider net in terms of the psychological variables of focus.

Entwicklung und Validierung einer ultrakurzen Operationalisierung des Konstrukts Optimismus-Pessimismus

Das Konstrukt Optimismus-Pessimismus ist aufgrund seiner vielfältigen Beziehungen zu gesellschaftlich relevanten Prozessen und Phänomen nicht nur für Psychologen, sondern auch für Forscher anderer Disziplinen von Interesse, zum Beispiel für Sozialwissenschaftler, Ökonomen und Gesundheitsforscher. In deren Untersuchungen sind aufgrund starker monetärer Restriktionen insbesondere ökonomische Operationalisierungen gefragt. Auf der Grundlage der weit verbreiteten Konstruktdefintion von Scheier und Carver (1985) , Optimismus-Pessimismus als generalisierte Erwartungen zukünftiger Ereignisse, wurde eine ökonomische Skala mit zwei Items entwickelt (Skala Optimismus-Pessimismus-2, SOP2). Die Formulierungen wurden in einem kognitiven Prestest für die anvisierte Zielgruppe, die deutschsprachige Bevölkerung, optimiert und anschließend in zwei umfangreichen heterogenen Stichproben validiert: einer Quotenstichprobe (N = 539) und einer Zufallsstichprobe (N = 1 134). Verschiedene Aspekte der psychometrischen Güte wurden geprüft. Die berichteten Befunde sprechen für die Reliabilität und Konstruktvalidität der SOP2. Auch mit der entwickelten ultrakurzen Operationalisierung ist es möglich die aus der Literatur bekannten Beziehungen im nomologischen Netzwerk des Konstrukts Optimismus-Pessimismus adäquat abzubilden.