General Functional Features Research Articles

Strategies of neutrophil diversification.

Neutrophils are formidable defenders. Their vast numbers, constant production, high cytotoxicity and capacity to produce extracellular traps, underlie their ability to efficiently protect in a microorganism-rich world. However, neutrophils are much more than immune sentinels, as evidenced by the expanding repertoire of functions discovered in the context of tissue homeostasis, regeneration or chronic pathologies. In this Perspective, we discuss general functional features of the neutrophil compartment that may be relevant in most, if not all, physiological scenarios in which they participate, including specialization in naïve tissues, transcriptional noise in the bloodstream as a potential strategy for diversification and functional bias in inflammatory sites. We intentionally present the reader with more questions than answers and propose models and approaches that we hope will shed new light onto the biology of these fascinating cells and spark new directions of research.

Music and Game Activity of Elementary School Students as an Aspect of Neuropedagogy

The research presented in the article testifies to the effectiveness of computer modeling in the conditions of musical and game activities of elementary school students. The relevance of the research is determined by the intensive development of innovative digital technologies that influence the development of society, form new approaches to the world, and contribute to the effective acquisition of new knowledge and skills as a neuropedagogical aspect. The purpose of the research is to study the effectiveness of the organization of musical and game activities as an aspect of younger schoolchildren by means of computer simulation. To increase the effectiveness of research, it is necessary to analyze aspects of neuropedagogy. In order to better "know" his student and decide on the choice of work methods in the future, it is advisable for the music teacher to evaluate not only his physical data and temperament, but also to find out by testing his general functional features organizations the brain and the leading modality. Accordingly, the main approaches to the organization of music and game activity were analyzed and the effectiveness of computer modeling in the context of the formation of music and game abilities and skills in younger schoolchildren was determined. The research methodology is formed by analytical and research methods, analysis of musical and game activities, methods of synthesis, analysis and interpretation, computer modeling technologies are used. The results of the study show that computer simulation is the most effective in the modern educational process.

Demonstration of Multi Statutory of the Adjective “Just” in Modern Adjectival English Lexicon

This article concerns the general functional features of an adjective in modern English, and in particular multistate lexical item “just”, which carries different meanings in different variants of combinatorics. The authors analyze the combinations used with the adjectival lexeme item “just” and reveal the categories that determine the degree of semantic content of each given statement. The need for a detailed study of multistate is due to insufficient knowledge of the categorization features and the functioning of multistate lexical item “just” in English language which has the feature of eurysemy (polysemy) that defines its broad compatibility in syntagmatic aspect.

MAPU 2.0: high-accuracy proteomes mapped to genomes

The MAPU 2.0 database contains proteomes of organelles, tissues and cell types measured by mass spectrometry (MS)-based proteomics. In contrast to other databases it is meant to contain a limited number of experiments and only those with very high-resolution and -accuracy data. MAPU 2.0 displays the proteomes of organelles, tissues and body fluids or conversely displays the occurrence of proteins of interest in all these proteomes. The new release addresses MS-specific problems including ambiguous peptide-to-protein assignments and it provides insight into general functional features on the protein level ranging from gene ontology classification to comprehensive SwissProt annotation. Moreover, the derived proteomic data are used to annotate the genomes using Distributed Annotation Service (DAS) via EnsEMBL services. MAPU 2.0 is a model for a database specifically designed for high-accuracy proteomics and a member of the ProteomExchange Consortium. It is available on line at http://www.mapuproteome.com.

Effect of synaptic plasticity on sensory coding and steady-state filtering properties in the electric sense

Our modeling study examines short-term plasticity at the synapse between afferents from electroreceptors and pyramidal cells in the electrosensory lateral lobe (ELL) of the weakly electric fish Apteronotus leptorhynchus. It focusses on steady-state filtering and coherence-based coding properties. While developed for electroreception, our study exposes general functional features for different mixtures of depression and facilitation. Our computational model, constrained by the available in vivo and in vitro data, consists of a synapse onto a deterministic leaky integrate-and-fire (LIF) neuron. The synapse is either depressing ( D), facilitating ( F) or both ( FD), and is driven by a sinusoidally or randomly modulated Poisson process. Due to nonlinearity, numerically computed input–output transfer functions are used to determine the filtering properties. The gain of the response at each sinusoidally modulated frequency is computed by dividing the fitted amplitudes of the input and output cycle histograms of the LIF models. While filtering is always low-pass for F alone, D alone exhibits a gain resonance (non-monotonicity) at a frequency that decreases with increasing recovery time constant of synaptic depression ( τ d ). This resonance is mitigated by the presence of F. For D, F and FD, coherence improves as the synaptic conductance time constant ( τ g ) increases, yet the mutual information per spike decreases. The information per spike for D and F follows opposite trends as their respective time constants increase. The broadband but non-monotonic gain and coherence functions seen in vivo suggest that D and perhaps FD dynamics are involved at this synapse. Our results further predict that the likely synaptic configuration is a slower τ g , e.g. via a mixture of AMPA and NMDA synapses, and a relatively smaller synaptic facilitation time constant ( τ f ) and larger τ d (with τ f smaller than τ d and τ g ). These results are compatible with known physiology.

Evolution of synthetic membranes for blood purification: the case of the Polyflux family.

Transport in biological systems is controlled by membranes functioning as barriers between compartments with various degrees of specificity. In 1972, Singer andNicolson [1] introduced a breakthrough view on structures of cell membranes with their fluid mosaic model. Their findings emerged along colloid chemistrybased organization of hydrophilic–hydrophobic polymer molecules and structures to form the cell membrane. Obviously, these principles also influenced the design of artificial membranes for therapeutic purposes. The general functional features involved in membrane separation processes, whether a natural cell membrane or an artificial membrane, concern either the process or the structure of the barrier, i.e. diffusion and convection of solutes along a pressure or concentration gradient, adsorption to generate a barrier for certain molecules, patch-like or mosaic-like structures to prevent or limit unspecific interaction, short transport channels for fast transport, nanoand micro-dimensions to suppress unspecific interaction and enable selectivity, narrow pore distribution to sharpen cut-off profiles, and optimized cross-filtration flux. In biological organisms, a number of additional functional elements of membranes are applied: active epithelial layers supported by basement membrane structures such as glomerular membranes, confluent tightly connected layers of endothelial cells, and strictly ordered hydrophilic–hydrophobic molecular arrangements in cellular bi-layer membranes. The function of the artificial kidney has relied from the beginning on principles laid down in renal physiology or, later, in biophysical principles in synthetic membranes whose functions were approaching those of the human glomerular membrane. Diffusion and convection predominantly have been combined to achieve the desired blood purification. Today, haemodialysis is basically divided into two categories: blood purification by low-flux and high-flux dialysis membranes [2–13]. Low-flux dialysis includes the standard haemodialysis technique in which dialysers with low hydraulic permeability are utilized. Blood and dialysate flows are at 250 and 500ml/min, respectively, and the average duration is 4 h. When dialyser surface area is increased, blood and dialysate flows are increased up to 400 and 800ml/min, respectively, and the treatment is defined in these circumstances as high efficiency haemodialysis. In this treatment, the clearance for small molecules is remarkably increased and the treatment time can generally be shortened, but the clearance for medium to large molecules is still very low due to the sieving characteristics of the membrane [14–30]. Classic cellulosic membranes such as Cuprophan were typically hydrogel-type low-flux membranes (i.e. permeability to water in the range of 5–6ml/h mmHg m), strongly hydrophilic and remarkably thin (6–12 mm) to permit an optimal utilization in diffusive transport of water-soluble solutes for treatments such as haemodialysis. On the other hand, classic high-flux synthetic membranes were originally fully hydrophobic, strongly asymmetric and with a wall thickness of 40–60 mm. They were originally employed in convective therapies such as haemofiltration [31] due to their high hydraulic permeability (i.e. 30–40ml/h mmHg m) and their elevated sieving coefficients. In a subsequent step, membrane structures have been adapted to fulfil the demand for increased diffusive permeability matched with tailored convective properties. This was achieved by (i) using polymer blends of hydrophilic and hydrophobic polymers; (ii) reduction of the wall thickness; and (iii) structural modifications Correspondence and offprint requests to: Claudio Ronco, Department of Nephrology, St Bortolo Hospital, Viale Rodolfi, 36100 Vicenza, Italy. E-mail: cronco@goldnet.it

OB-fold: growing bigger with functional consistency.

It was predicted that the folding space for various protein sequences is restricted and a maximum of 1000 protein folds could be expected. Although, there were about 648 folds identified, general functional features of individual folds is not thoroughly studied. We selected OB-fold, which is supposed to be an oligonucleotide and oligosaccharide binding fold to study the general functional features. OB-fold is a small beta-barrel fold formed from 5 strands connected by modulating loops. We observed consistently 2 or 3 loops on the same face of barrel acting as clamps to bind to their ligands. Depending on the ligand, which could be a single or double stranded DNA/RNA or an oligosaccharide, and their conformational properties the loops change in length and sequence to accommodate various ligands. Different classes of OB-folded proteins were analyzed and found that the functional features are retained in spite of negligible sequence homology among various proteins studied.

Effects of activity on contractions of normal and dystrophic mouse muscles.

Excised gastrocnemii of normal and dystrophic mice, directly stimulated in long series of isometric twitches or tetani, show different fatigue patterns. During a series of 1,200 maximal twitches, developed tension drops much more slowly in dystrophic responses so that final output relative to initial is: dystrophic, 70%, normal, 10%. A similar but smaller difference holds for a tetanus series. Pronounced quantitative and qualitative distinctions between the two muscle types also appear in the changes of other twitch characteristics: relaxation time and rate, and contraction rate but not time. The qualitatively distinct fatigue pattern of the dystrophic muscle is dependent not on diffusional differences stemming from its smaller bulk, but on some basic dissimilarity inherent in the dystrophic myopathy. The possible nature of this dissimilarity is discussed in relation to general functional features of fatigue and to special aspects of dystrophic muscle concerned with metabolism, intensity property of the active state, and role of the relaxing factor.