SorLA restricts TNFα release from microglia to shape a glioma-supportive brain microenvironment

SorLA, encoded by the gene SORL1, is an intracellular sorting receptor of the VPS10P domain receptor gene family. Although SorLA is best recognized for its ability to shuttle target proteins between intracellular compartments in neurons, recent data suggest that also its microglial expression can be of high relevance for the pathogenesis of brain diseases, including glioblastoma (GBM). Here, we interrogated the impact of SorLA on the functional properties of glioma-associated microglia and macrophages (GAMs). In the GBM microenvironment, GAMs are re-programmed and lose the ability to elicit anti-tumor responses. Instead, they acquire a glioma-supporting phenotype, which is a key mechanism promoting glioma progression. Our re-analysis of published scRNA-seq data from GBM patients revealed that functional phenotypes of GAMs are linked to the level of SORL1 expression, which was further confirmed using in vitro models. Moreover, we demonstrate that SorLA restrains secretion of TNFα from microglia to restrict the inflammatory potential of these cells. Finally, we show that loss of SorLA exacerbates the pro-inflammatory response of microglia in the murine model of glioma and suppresses tumor growth.

Herbal Polyphenols as Selenium Reducers in the Green Synthesis of Selenium Nanoparticles: Antibacterial and Antioxidant Capabilities of the Obtained SeNPs

Selenium is an essential trace element for the proper functioning of the human body. In recent years, great attention has been paid to selenium nanoparticles (SeNPs) due to their potential for medicinal applications. In this study, herbal extracts were used in the green synthesis of SeNPs. The influence of herbal species, the ratio of the reagents, and post-reaction heating on the antibacterial and antioxidant properties of obtained SeNPs were investigated. The relationship between these properties and the physical parameters of obtained nanoparticles (e.g., size, shape) was also studied. It has been proven that SeNPs showed higher antioxidant and antibacterial properties in comparison to herbal extracts taken for their synthesis. Heating of the post-reaction mixture did not affect the SeNP size, shape, or other studied properties.

Enhancing the Green Synthesis of Glycerol Carbonate: Carboxylation of Glycerol with CO2 Catalyzed by Metal Nanoparticles Encapsulated in Cerium Metal-Organic Frameworks

The reaction of glycerol with CO2 to produce glycerol carbonate was performed successfully in the presence of gold nanoparticles (AuNPs) supported by a metal-organic framework (MOF) constructed from mixed carboxylate (terephthalic acid and 1,3,5-benzenetricarboxylic acid). The most efficient were two AuNPs@MOF catalysts prepared from pre-synthesized MOF impregnated with Au3+ salt and subsequently reduced to AuNPs using H2 (catalyst 4%Au(H2)@MOF1) or reduced with NaBH4 (catalyst 4%Au@PEI-MOF1). Compared to existing catalysts, AuNPs@MOFs require simple preparation and operate under mild and sustainable conditions, i.e., a much lower temperature and the lowest CO2 overpressure ever reported, with MgCO3 having been found to be the optimal dehydrating agent. Although the yield of the process is still not competitive with previously developed systems, the most promising advantage is the highest TOF (78 h-1) ever reported for this reaction. The optimal parameters observed for AuNPs were also tested on AgNPs and CuNPs with promising results, suggesting their great potential for industrial application. The catalysts were characterized by XRD, TEM, SEM-EDS, ICP-MS, XPS, and porosity measurements, confirming that AuNPs are present in low concentration, uniformly distributed, and confined to the cavities of the MOF.

Ammonium treatment inhibits cell cycle activity and induces nuclei endopolyploidization in Arabidopsis thaliana

MAIN CONCLUSION

This study determined the effect of ammonium supply on the cell division process and showed that ammonium-dependent elevated reactive oxygen species production could mediate the downregulation of the cell cycle-related gene expression. Plants grown under high-ammonium conditions show stunted growth and other toxicity symptoms, including oxidative stress. However, how ammonium regulates the development of plants remains unknown. Growth is defined as an increase in cell volume or proliferation. In the present study, ammonium-related changes in cell cycle activity were analyzed in seedlings, apical buds, and young leaves of Arabidopsis thaliana plants. In all experimental ammonium treatments, the genes responsible for regulating cell cycle progression, such as cyclin-dependent kinases and cyclins, were downregulated in the studied tissues. Thus, ammonium nutrition could be considered to reduce cell proliferation; however, the cause of this phenomenon may be secondary. Reactive oxygen species (ROS), which are produced in large amounts in response to ammonium nutrition, can act as intermediates in this process. Indeed, high ROS levels resulting from H2O2 treatment or reduced ROS production in rbohc mutants, similar to ammonium-triggered ROS, correlated with altered cell cycle-related gene expression. It can be concluded that the characteristic ammonium growth suppression may be executed by enhanced ROS metabolism to inhibit cell cycle activity. This study provides a base for future research in determining the mechanism behind ammonium-induced dwarfism in plants, and strategies to mitigate such stress.

On the possibility of the existence of orienting hydrodynamic steering effects in the kinetics of receptor-ligand association

In the vast majority of biologically relevant cases of receptor-ligand complex formation, the binding site of the receptor is a small part of its surface, and moreover, formation of a biologically active complex often requires a specific orientation of the ligand relative to the binding site. Before the formation of the initial form of the complex, only long-range, electrostatic and hydrodynamic interactions can act between the ligand approaching the binding site and the receptor. In this context, the question arises whether as a result of these interactions, there is a pre-orientation of the ligand towards the binding site, which to some extent would accelerate the formation of the complex. The role of electrostatic interactions in the orientation of the ligand relative to the binding site of the receptor is well documented. The analogous role of hydrodynamic interactions, although assessed as very significant by Brune and Kim (PNAS 91, 2930-2934, (1994)), is still debatable. In this article, I present the current state of knowledge on this subject and consider the possibilities of demonstrating the orienting effect of hydrodynamic interactions in the processes of receptor-ligand association, in an experimental way supported by computer simulations.

Did Cognitive Attentional Syndrome Symptoms Predict Stress- and Trauma-Related Symptoms in the Initial Phase of the COVID-19 Pandemic? Results from a Two-Wave Study on a Sample of Polish Internet Users

BACKGROUND

According to metacognitive theory, Cognitive Attentional Syndrome (CAS) is a transdiagnostic factor and a main mechanism of psychopathology maintenance. The main goal of this study is to examine whether CAS predicted stress- and trauma-related symptomatology in the first months of the COVID-19 pandemic and three months later.

METHODS

Initially, 1792 participants were recruited online via social media; the data were collected at two time points. The measures included the Cognitive Attentional Syndrome Questionnaire, the Adjustment Disorder-New Module 20, the International Trauma Questionnaire, and additional measures.

RESULTS

Structural equation modeling was conducted in order to determine the relations between the reported stressors, CAS, and symptomatology. At both time points, CAS was a significant mediator between the stressors and symptoms of adjustment disorder. Despite the decrease in the intensity of adjustment disorder symptoms between waves, it was a significant predictor of other psychopathologies at both time points, except for traumatic stress.

CONCLUSIONS

The findings confirm the assumption that CAS is a transdiagnostic factor of psychopathology and has a mediating role in the relationship between stressors and adjustment disorder and co-occurring symptomatology. The effect was particularly significant in the initial phase of the pandemic, which was highly stressful for many people.

Euler characteristic curves and profiles: a stable shape invariant for big data problems

Tools of topological data analysis provide stable summaries encapsulating the shape of the considered data. Persistent homology, the most standard and well-studied data summary, suffers a number of limitations; its computations are hard to distribute, and it is hard to generalize to multifiltrations and is computationally prohibitive for big datasets. In this article, we study the concept of Euler characteristics curves for 1-parameter filtrations and Euler characteristic profiles for multiparameter filtrations. While being a weaker invariant in one dimension, we show that Euler characteristic-based approaches do not possess some handicaps of persistent homology; we show efficient algorithms to compute them in a distributed way, their generalization to multifiltrations, and practical applicability for big data problems. In addition, we show that the Euler curves and profiles enjoy a certain type of stability, which makes them robust tools for data analysis. Lastly, to show their practical applicability, multiple use cases are considered.

Religiosity and the Spread of COVID-19: A Multinational Comparison

This article considers the relationships between population religiosity and the coronavirus pandemic situation across different countries. Country-level analyses were based on data from the World Values Survey, Worldometer, and International Monetary Fund covering information about internal (beliefs) and external (practices) religiosity, religious fundamentalism, the COVID-19 pandemic, and the economic situation at two time points in 47 countries. Results showed that declared attendance at religious services is related to more COVID-19 infections and deaths, as well as when controlling for gross domestic product per capita and the number of coronavirus tests per 1 million population. This effect remained in the longitudinal perspective (of six months) and extended from external religiosity only, to both internal and external religiosity indices.

Progress in Diamanes and Diamanoids Nanosystems for Emerging Technologies

New materials are the backbone of their technology-driven modern civilization and at present carbon nanostructures are the leading candidates that have attracted huge research activities. Diamanes and diamanoids are the new nanoallotropes of sp3 hybridized carbon which can be fabricated by proper functionalization, substitution, and via Birch reduction under controlled pressure using graphitic system as a precursor. These nanoallotropes exhibit outstanding electrical, thermal, optical, vibrational, and mechanical properties, which can be an asset for new technologies, especially for quantum devices, photonics, and space technologies. Moreover, the features like wide bandgap, tunable thermal conductivity, excellent thermal insulation, etc. make diamanes and diamanoids ideal candidates for nano-electrical devices, nano-resonators, optical waveguides, and the next generation thermal management systems. In this review, diamanes and diamanoids are discussed in detail in terms of its historical prospect, method of synthesis, structural features, broad properties, and cutting-edge applications. Additionally, the prospects of diamanes and diamanoids for new applications are carefully discussed. This review aims to provide a critical update with important ideas for a new generation of quantum devices based on diamanes and diamanoids which are going to be an important topic in the future of carbon nanotechnology.

Protecting Breastfeeding during the COVID-19 Pandemic: A Scoping Review of Perinatal Care Recommendations in the Context of Maternal and Child Well-Being

The objective of this scoping review is to determine to what extent the recommendations on perinatal care protect breastfeeding during the COVID-19 pandemic. The review follows the PRISMA ScR Extension guidelines. The research was conducted in Scopus, Medline via Pubmed, and Web of Science databases from 1 March 2020 to 31 May 2021, using 392 combinations of keywords. We searched for reviews and original papers published in English providing recommendations on delivery mode, companion during labor, the possibility of skin-to-skin contact (SSC), breastfeeding, and visitors policy. After screening, 86 out of 8416 publications qualified for data extraction. The majority of them indicated that COVID-19 infection is not a sufficient reason for a cesarean section; however, on a national level, cesarean births in severely ill patients were overrepresented. A significant number of recommendations deprived mothers of the necessary support during their labor and stay in the maternity ward. A shared decision-making model was hardly visible. Only the earliest COVID-19 recommendations suspended direct breastfeeding; in later publications, decisions were related to the mother's health, but other options of natural feeding were rarely discussed.

Constrained peptides mimic a viral suppressor of RNA silencing

The design of high-affinity, RNA-binding ligands has proven very challenging. This is due to the unique structural properties of RNA, often characterized by polar surfaces and high flexibility. In addition, the frequent lack of well-defined binding pockets complicates the development of small molecule binders. This has triggered the search for alternative scaffolds of intermediate size. Among these, peptide-derived molecules represent appealing entities as they can mimic structural features also present in RNA-binding proteins. However, the application of peptidic RNA-targeting ligands is hampered by a lack of design principles and their inherently low bio-stability. Here, the structure-based design of constrained α-helical peptides derived from the viral suppressor of RNA silencing, TAV2b, is described. We observe that the introduction of two inter-side chain crosslinks provides peptides with increased α-helicity and protease stability. One of these modified peptides (B3) shows high affinity for double-stranded RNA structures including a palindromic siRNA as well as microRNA-21 and its precursor pre-miR-21. Notably, B3 binding to pre-miR-21 inhibits Dicer processing in a biochemical assay. As a further characteristic this peptide also exhibits cellular entry. Our findings show that constrained peptides can efficiently mimic RNA-binding proteins rendering them potentially useful for the design of bioactive RNA-targeting ligands.

A library of coiled-coil domains: from regular bundles to peculiar twists

MOTIVATION

Coiled coils are widespread protein domains involved in diverse processes ranging from providing structural rigidity to the transduction of conformational changes. They comprise two or more α-helices that are wound around each other to form a regular supercoiled bundle. Owing to this regularity, coiled-coil structures can be described with parametric equations, thus enabling the numerical representation of their properties, such as the degree and handedness of supercoiling, rotational state of the helices, and the offset between them. These descriptors are invaluable in understanding the function of coiled coils and designing new structures of this type. The existing tools for such calculations require manual preparation of input and are therefore not suitable for the high-throughput analyses.

RESULTS

To address this problem, we developed SamCC-Turbo, a software for fully automated, per-residue measurement of coiled coils. By surveying Protein Data Bank with SamCC-Turbo, we generated a comprehensive atlas of ∼50 000 coiled-coil regions. This machine learning-ready dataset features precise measurements as well as decomposes coiled-coil structures into fragments characterized by various degrees of supercoiling. The potential applications of SamCC-Turbo are exemplified by analyses in which we reveal general structural features of coiled coils involved in functions requiring conformational plasticity. Finally, we discuss further directions in the prediction and modeling of coiled coils.

AVAILABILITY AND IMPLEMENTATION

SamCC-Turbo is available as a web server (https://lbs.cent.uw.edu.pl/samcc_turbo) and as a Python library (https://github.com/labstructbioinf/samcc_turbo), whereas the results of the Protein Data Bank scan can be browsed and downloaded at https://lbs.cent.uw.edu.pl/ccdb.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Photosynthesis of the Cyanidioschyzon merolae cells in blue, red, and white light

Photosynthesis and respiration rates, pigment contents, CO2 compensation point, and carbonic anhydrase activity in Cyanidioschizon merolae cultivated in blue, red, and white light were measured. At the same light quality as during the growth, the photosynthesis of cells in blue light was significantly lowered, while under red light only slightly decreased as compared with white control. In white light, the quality of light during growth had no effect on the rate of photosynthesis at low O2 and high CO2 concentration, whereas their atmospheric level caused only slight decrease. Blue light reduced markedly photosynthesis rate of cells grown in white and red light, whereas the effect of red light was not so great. Only cells grown in the blue light showed increased respiration rate following the period of both the darkness and illumination. Cells grown in red light had the greatest amount of chlorophyll a, zeaxanthin, and β-carotene, while those in blue light had more phycocyanin. The dependence on O2 concentration of the CO2 compensation point and the rate of photosynthesis indicate that this alga possessed photorespiration. Differences in the rate of photosynthesis at different light qualities are discussed in relation to the content of pigments and transferred light energy together with the possible influence of related processes. Our data showed that blue and red light regulate photosynthesis in C. merolae for adjusting its metabolism to unfavorable for photosynthesis light conditions.

You don't have to be rich to save money: On the relationship between objective versus subjective financial situation and having savings

Saving is an important financial behavior that provides an individual with psychological security and boosts his/her overall sense of well-being. For this reason, scientists and practitioners have attempted to understand why some people save when others do not. One of the most common explanations for this phenomenon is that those individuals who earn more should be more willing to save their money. In line with this logic, people who have more money should be more likely to have savings. Considering the results of prior research, we expected objective financial situation (income) to be positively linked to having savings (i.e., propensity to have savings and the exact amount of savings). At the same time, however, we assumed that subjective financial situation (perception) should also be positively related to these variables. To test our assumptions, we conducted a nationwide representative survey (N = 1048) among Polish respondents, asking them about their objective and subjective financial situation. The results of a regression analysis showed that objective financial situation was indeed significantly positively related to having savings. However, subjective financial situation was also positively correlated with having savings (even when we controlled for objective financial situation and demographic variables). We discuss the implications of the links between objective versus subjective financial situations and having savings.