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Natural rewards, such as food, and sex are appetitive stimuli available for animals in their natural environment. Similarly, addictive rewards such as drugs of abuse possess strong, positive valence, but their action relies on their pharmacological properties. Nevertheless, it is believed that both of these kinds of rewards activate similar brain circuitry. The present study aimed to discover which parts of the brain process the experience of natural and addictive rewards. To holistically address this question, we used a single-cell whole-brain imaging approach to find patterns of activation for acute and prolonged sucrose and cocaine exposure. We analyzed almost 400 brain structures and created a brain-wide map of specific, c-Fos-positive neurons engaged by these rewards. Acute but not prolonged sucrose exposure triggered a massive c-Fos expression throughout the brain. Cocaine exposure on the other hand potentiated c-Fos expression with prolonged use, engaging more structures than sucrose treatment. The functional connectivity analysis unraveled an increase in brain modularity after exposure to both types of rewards. This modularity stabilized during prolonged sucrose, but not cocaine, intake. To check whether discrepancies between the processing of both types of rewards can be found on a cellular level, we further studied the nucleus accumbens, one of the most strongly activated brain structures by both sucrose and cocaine experience. We found a high overlap between natural and addictive rewards on the level of c-Fos expression. Electrophysiological measurements of cellular correlates of synaptic plasticity revealed that natural and addictive rewards alike induce the accumulation of silent synapses. These results strengthen the hypothesis that in the nucleus accumbens drugs of abuse cause maladaptive neuronal plasticity in the circuitry that typically processes natural rewards.

We begin our considerations with claiming that in the process of teaching a foreign language, the primary aim is to develop the pragmatic and communicative competence which means, among others, the ability to construct utterances that are correct and adequate for a particular communicative situation. The subject of this article is to present formal strategies concerning the act of apology, employed by Polish students in the process of learning Portuguese as a foreign language. Since the act of apology can be considered as one of the most essential acts of speech in communication, it is, therefore, important to verify which type of the act of apology is employed by students who are not native users of the Portuguese language.

Artykuł prezentuje specyfikę stosunku umowy o dzieło w kontekście systemu ubezpieczeń społecznych. Celem tekstu jest rozróżnienie okoliczności, jakie towarzyszą zawarciu tej umowy, oraz konsekwencji niewłaściwego zakwalifikowania danego zobowiązania jako umowy o dzieło wobec jej stron (np. konieczności poniesienia dodatkowych kosztów w przypadku zakwalifikowania jej finalnie jako innej umowy cywilnoprawnej). Artykuł wyjaśnia, w jakich sytuacjach należy objąć zawierane umowy o dzieło obowiązkowym ubezpieczeniem społecznym, jak również przedstawia korzyści i zagrożenia wynikające z zawarcia takiej umowy. Osiągnięciu wyznaczonego celu podporządkowano układ niniejszego tekstu oraz wykorzystane metody badawcze: dogmatyczno-prawną oraz teoretyczno-prawną, obejmujące krytyczną analizę powszechnie obowiązujących przepisów, literatury przedmiotu, orzecznictwa. Analiza zgromadzonego materiału badawczego pozwoliła na potwierdzenie wielu wątpliwości co do wykładni i stosowania powszechnie obowiązujących przepisów we wskazanym zakresie, jak również konieczności indywidualnego interpretowania każdej umowy. Dodatkowo artykuł rozpatruje wpływ regulacji w sprawie COVID-19.

The paper addresses the issues of relationships in distance education. These problems are important because good relationships are among the key determinants of both the quality of education and learning outcomes. The new educational conditions brought about by the COVID-19 pandemic have become a threat to building and strengthening the school community's relationships. The need to switch to distance education from one day to the next was a huge challenge for teachers, students, and parents. Initially, teachers focused mainly on technical issues and finding ways to implement core curricula. There was a risk that in distance education, where contact is mediated, it would be difficult for teachers to foster relationships. Furthermore, taking care of students' psychological needs, including the need for relationships, should be a priority in these conditions to provide an antidote to the psychological difficulties associated with isolation and online learning. The purpose of this study was to examine the importance attached by early school education teachers to relationships as well as how and to what extent they build and maintain relationships and create a community in distance education. The research was conducted using the interview method and included early school education teachers. The results obtained represent examples of good practice in fostering relationships while teaching online.

The article presents research results on the possibility of using ICTs in a speech therapist’s practice. The results of the study show that students have changed their view of the place of ICTs in speech therapy. The COVID-19 pandemic has changed their attitudes towards ICTs. For them, this crisis has become an opportunity for the development of their own skills to use ICTs in their future professional work.

This paper explores how a changing social situation in late colonial northern India influenced issues related to marriage. The most controversial matters, also reflected in Hindi literature of the time, were: proper age at marriage, ritual concerns, marriage expenses as well as effects of child marriage and child widows. The paper draws mainly on Hindi novels by Ayodhya Singh Upadhyay and Kishorilal Goswami, published in the beginning of the twentieth century. For the most part, conservative and didactic in their outlook, they put forward interesting postulates concerning disputable matters. Some of the ideas, like reducing unnecessary wedding expenses, are worth considering even today. The analysis of literary sources also reveals the expectations of future brides and grooms. The attention paid by Hindi writers to a number of marriage practices confirms the status of marriage as one of the most important social institutions.

Deposited on hot work tool steel substrate coating system composed of AlTiCrN film covered by diamond-like carbon (DLC)-based lubricant, was the subject of the studies. The AlTiCrN and DLC layers were deposited by PVD lateral rotating ARC-cathodes (LARC) and PACVD technology on the X40CrMoV5-1 respectively. This paper provides an analysis of the microstructure, mechanical and tribological properties. Several surface sensitive techniques and methods, i.e. High Resolution Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM), Raman spectroscopy and ball-on-disk were used to performed study of the coating. TEM investigation shows an amorphous character of DLC layer. It was found that tested AlTiCrN layer has nanostructural character with fine crystallites. In sliding dry friction conditions the friction coefficient for the investigated elements is set in the range between 0.02-0.04. The investigated coating reveals high wear resistance. The coating demonstrated good adhesion to the substrate.

The polar, sub-cellular localization of PIN auxin efflux carriers determines the direction of intercellular auxin flow, thus defining the spatial aspect of auxin signalling. Dynamic, transcytosis-like relocalizations of PIN proteins occur in response to external and internal signals, integrating these signals into changes in auxin distribution. Here, we examine the cellular and molecular mechanisms of polar PIN delivery and transcytosis. The mechanisms of the ARF-GEF-dependent polar targeting and transcytosis are well conserved and show little variations among diverse Arabidopsis ecotypes consistent with their fundamental importance in regulating plant development. At the cellular level, we refine previous findings on the role of the actin cytoskeleton in apical and basal PIN targeting, and identify a previously unknown role for microtubules, specifically in basal targeting. PIN protein delivery to different sides of the cell is mediated by ARF-dependent trafficking with a previously unknown complex level of distinct ARF-GEF vesicle trafficking regulators. Our data suggest that alternative recruitment of PIN proteins by these distinct pathways can account for cell type- and cargo-specific aspects of polar targeting, as well as for polarity changes in response to different signals. The resulting dynamic PIN positioning to different sides of cells defines a three-dimensional pattern of auxin fluxes within plant tissues.

SummaryCell polarity manifested by the polar cargo delivery to different plasma-membrane domains is a fundamental feature of multicellular organisms. Pathways for polar delivery have been identified in animals; prominent among them is transcytosis, which involves cargo movement between different sides of the cell [1]. PIN transporters are prominent polar cargoes in plants, whose polar subcellular localization determines the directional flow of the signaling molecule auxin [2, 3]. In this study, we address the cellular mechanisms of PIN polar targeting and dynamic polarity changes. We show that apical and basal PIN targeting pathways are interconnected but molecularly distinct by means of ARF GEF vesicle-trafficking regulators. Pharmacological or genetic interference with the Arabidopsis ARF GEF GNOM leads specifically to apicalization of basal cargoes such as PIN1. We visualize the translocation of PIN proteins between the opposite sides of polarized cells in vivo and show that this PIN transcytosis occurs by endocytic recycling and alternative recruitment of the same cargo molecules by apical and basal targeting machineries. Our data suggest that an ARF GEF-dependent transcytosis-like mechanism is operational in plants and provides a plausible mechanism to trigger changes in PIN polarity and hence auxin fluxes during embryogenesis and organogenesis.

It has been demonstrated that high blood vascular endothelial growth factor (VEGF) levels in patients with myocardial infarction decrease rapidly after reperfusion, possibly in response to heparin administration. We measured serum VEGF concentration before and after heparin infusion in 105 patients with ST-elevation acute myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI). Serum VEGF concentration in patients with STEMI was significantly higher than in healthy controls. After PCI, the concentration of VEGF decreased by approximately 70%, with the greatest decrease seen in patients with the highest initial VEGF levels. To determine whether heparin could decrease VEGF concentration by sequestering VEGF in the endothelium, a fixed dose of recombinant VEGF was incubated for 40 minutes with EA.hy926 endothelial cells in vitro. Recovery of VEGF from medium after culture was decreased by up to 15% with increasing doses of heparin. Concentration of VEGF did not change in the absence of heparin and/or endothelial cells. In conclusion, these results suggest that a rapid decrease in blood VEGF after PCI may be related to the administration of heparin, which binds simultaneously to VEGF and endothelial cells.

There is a growing demand for methods that allow rapid and reliable in situ localization of proteins in plant cells. The immunocytochemistry protocol presented here can be used routinely to observe protein localization patterns in tissue sections of various plant species. This protocol is especially suitable for plant species with more-complex tissue architecture (such as maize, Zea mays), which makes it difficult to use an easier whole-mount procedure for protein localization. To facilitate the antibody-antigen reaction, it is necessary to include a wax-embedding and tissue-sectioning step. The protocol consists of the following procedures: chemical fixation of tissue, dehydration, wax embedding, sectioning, dewaxing, rehydration, blocking and antibody incubation. The detailed protocol, recommended controls and troubleshooting are presented here, along with examples of applications.

Intercellular flow of the phytohormone auxin underpins multiple developmental processes in plants. Plant-specific pin-formed (PIN) proteins and several phosphoglycoprotein (PGP) transporters are crucial factors in auxin transport–related development, yet the molecular function of PINs remains unknown. Here, we show that PINs mediate auxin efflux from mammalian and yeast cells without needing additional plant-specific factors. Conditional gain-of-function alleles and quantitative measurements of auxin accumulation in Arabidopsis and tobacco cultured cells revealed that the action of PINs in auxin efflux is distinct from PGP, rate-limiting, specific to auxins, and sensitive to auxin transport inhibitors. This suggests a direct involvement of PINs in catalyzing cellular auxin efflux.

Plant development displays an exceptional plasticity and adaptability that involves the dynamic, asymmetric distribution of the phytohormone auxin. Polar auxin flow, which requires polarly localized transport facilitators of the PIN family, largely contributes to the establishment and maintenance of the auxin gradients. Functionally overlapping action of PIN proteins mediates multiple developmental processes, including embryo formation, organ development and tropisms. Here we show that PIN proteins exhibit synergistic interactions,which involve cross-regulation of PIN gene expression in pin mutants or plants with inhibited auxin transport. Auxin itself positively feeds back on PIN gene expression in a tissue-specific manner through an AUX/IAA-dependent signalling pathway. This regulatory switch is indicative of a mechanism by which the loss of a specific PIN protein is compensated for by auxin-dependent ectopic expression of its homologues. The compensatory properties of the PIN-dependent transport network might enable the stabilization of auxin gradients and potentially contribute to the robustness of plant adaptive development.

Nitric oxide (NO) is one of the secretory products of macrophages. Abundant evidence indicates that NO contributes to the host defence functions of these cells. The aim of this study was to test the hypothesis that the induced form of NO synthase (iNOS) may participate in the defence of the host against Trichinella. To investigate whether NO was produced during trichinellosis, we examined NO serum levels as an indicator of NO production by iNOS in mice infected with T. spiralis. A statistically significant increase in the NO serum levels relative to the control group (uninfected animals) was observed during weeks 2-8 post-infection. This increase suggest that iNOS is induced during experimental trichinellosis in mice. In the next stage of our study, we compared the NO synthesis by peritoneal macrophages isolated from infected mice with those from uninfected control. A statistically significant increase in the NO release from macrophages obtained from infected mice was noticed on days 7, 21, 29, 43 and 63 post-infection. These results suggest that infection with T. spiralis induces NO production by macrophages.

In contrast to animals, little is known about pattern formation in plants. Physiological and genetic data suggest the involvement of the phytohormone auxin in this process. Here, we characterize a novel member of the PIN family of putative auxin efflux carriers, Arabidopsis PIN4, that is localized in developing and mature root meristems. Atpin4 mutants are defective in establishment and maintenance of endogenous auxin gradients, fail to canalize externally applied auxin, and display various patterning defects in both embryonic and seedling roots. We propose a role for AtPIN4 in generating a sink for auxin below the quiescent center of the root meristem that is essential for auxin distribution and patterning.

Plant development is characterized by a profound ability to regenerate and form tissues with new axes of polarity. An unsolved question concerns how the position within a tissue and cues from neighboring cells are integrated to specify the polarity of individual cells. The canalization hypothesis proposes a feedback effect of the phytohormone auxin on the directionality of intercellular auxin flow as a means to polarize tissues. Here we identify a cellular and molecular mechanism for canalization. Local auxin application, wounding, or auxin accumulation during de novo organ formation lead to rearrangements in the subcellular polar localization of PIN auxin transport components. This auxin effect on PIN polarity is cell-specific, does not depend on PIN transcription, and involves the Aux/IAA-ARF (indole-3-acetic acid-auxin response factor) signaling pathway. Our data suggest that auxin acts as polarizing cue, which links individual cell polarity with tissue and organ polarity through control of PIN polar targeting. This feedback regulation provides a conceptual framework for polarization during multiple regenerative and patterning processes in plants.

Polar flow of the phytohormone auxin requires plasma membrane‐associated PIN proteins and underlies multiple developmental processes in plants. Here we address the importance of the polarity of subcellular PIN localization for the directionality of auxin transport in Arabidopsis thaliana. Expression of different PINs in the root epidermis revealed the importance of PIN polar positions for directional auxin flow and root gravitropic growth. Interfering with sequence-embedded polarity signals directly demonstrates that PIN polarity is a primary factor in determining the direction of auxin flow in meristematic tissues. This finding provides a crucial piece in the puzzle of how auxin flow can be redirected via rapid changes in PIN polarity.

Root gravitropism describes the orientation of root growth along the gravity vector and is mediated by differential cell elongation in the root meristem. This response requires the coordinated, asymmetric distribution of the phytohormone auxin within the root meristem, and depends on the concerted activities of PIN proteins and AUX1 — members of the auxin transport pathway. Here, we show that intracellular trafficking and proteasome activity combine to control PIN2 degradation during root gravitropism. Following gravi-stimulation, proteasome-dependent variations in PIN2 localization and degradation at the upper and lower sides of the root result in asymmetric distribution of PIN2. Ubiquitination of PIN2 occurs in a proteasome-dependent manner, indicating that the proteasome is involved in the control of PIN2 turnover. Stabilization of PIN2 affects its abundance and distribution, and leads to defects in auxin distribution and gravitropic responses. We describe the effects of auxin on PIN2 localization and protein levels, indicating that redistribution of auxin during the gravitropic response may be involved in the regulation of PIN2 protein.

The aim of the study was to appraise the level of interleukin 5, 8 in secretion from the nose in etiology of chronic inflammatory state of the nose and nasal sinuses. The group of 32 patients classified as group suffered from the inflammatory state of nasal sinuses described in the International Nose and sinuses Conference in Princeton, New Jersey 1993 was examined. The level of IL-5 and IL-8 with ELISA method was indicated and the cytological examination was carried out. In the material a predominance of neutrophils implying a bacterial etiology of illness was observed. Simultaneously the high level of IL 8 (13-1393 average 2.7 +/- 6.1) was indicated.

Using the radiometric method, the activity of acetylcholinesterase (AChE, E.C. 3.1.1.7) was studied in seedlings of wild type (WT) and of phytochrome mutants of tomato ( Lycopersicon esculentum Mill.). The activity of this enzyme was inhibited by an excess of substrate and by two well-known inhibitors of animal AChE, eserine and neostigmine. The activity of AChE was found in all etiolated organs as well as in light-grown seedlings. Under both conditions, the highest level of the enzyme activity was detected in cotyledons and the lowest one in root tissue. The enzyme activity was phytochrome-controlled. In WT etiolated seedlings red (R) light decreased AChE activity, whereas far red (FR) light abolished the red light effect. Furthermore, in light-grown WT seedlings the level of the enzyme activity was about twice higher than in etiolated plants. However, in the aurea phytochrome mutant of tomato, deficient in biosynthesis of a phytochrome chromophore, light had no effect on the AChE activity. In case of hp , fri and tri mutant seedlings, R and FR affected the AChE activity in a different way. Based on our results, we suggest that the type I of phytochrome is involved in the regulation of AChE activity. The type II of this photoreceptor influences the rate of the AChE synthesis de novo.

Biochemical and genetic studies have identified peptides that play crucial roles in plant growth and development, including defence mechanisms in response to wounding by pests, the control of cell division and expansion, and pollen self-incompatibility. The first two signalling peptides to be described in plants were tomato systemin and phytosulfokine (PSK). There is also biochemical evidence that natriuretic peptide-like molecules, immunologically-relatedt o those found in animals,m ay exist in plants. Another example of signalling peptide is ENOD40, a product of a gene, which became active early in the root nodulation process following Rhizobium infection of legumes. Other predicted bioactive peptides or oligopeptides have been identified by means of genetic, rather then biochemical methods. The Arabidopsis CLAVATA3 protein is required for the correct organization of the shoot apical meristem and the pollen S determinant S-locus cysteine-rich protein (SCR also called S-locus protein 11, SP11). The plant signalling peptides discovered so far are involved in various processes and play an important role in communication between cells or organs, respectively. This review will focus on these peptides and their role in intercellular signalling.

It is believed that changes in the serum level of cytokines (e.g. IL-6) are natural consequence of physiological aging. On the other hand, increased level of proinflammatory cytokines (Il-6 and IL-8) occurs during inflammation. The aim of the study was to estimate serum levels of IL-6 and IL-8 to check if the possible increase in IL-6 in elderly is caused by diseases rather than by aging. The study involved 30 healthy elderly (Group B: age 71.1 +/- 5.5 years; range 65-89 year) and 29 healthy young subjects (Group K: age 27.0 +/- 4.2 years, range: 21-37 years). In every subject serum level of IL-6 and IL-8 was assessed with immunoassay techniques using ELISA. The amount of subjects with the detectable level of IL-6 was comparable in both in group B and K (38.5% vs. 27.6%). The IL-6 level was almost 5 times higher in older group but the difference was not statistically significant (10.89 +/- 22.65 vs. 2.17 +/- 4.94). Similarly, the amount of subjects with the detectable level of IL-8 was comparable in both in B and K group (20.7% vs. 18.2%) and the IL-8 level was almost 5 times higher in older group vs. younger one but the difference was not statistically significant (9.61 +/- 20.89 vs. 2.65 +/- 6.09 pg/ml). In both studied groups, subjects with detectable level of IL-6 (Group B1 and K1, respectively) had also higher IL-8 level in comparison to subjects with non-detectable IL-6 (Group B2 and K2) (B1: 18.06 +/- 27.15 pg/ml, B2: 4.33 +/- 14.43 pg/ml, p = 0.052 and K1: 7.65 +/- 8.69 pg/ml, K2: 0.74 +/- 3.41 pg/ml, p0.01). The amount of subjects with detectable level of IL-8 was 40% in Group B1 vs. 12.5% in Group B2 and 50% in Group K1 vs. 4.5% in Group K2 (p0.02). In conclusion, our study showed that increased level of IL-6 in elderly seems to reflect the diseases rather than aging itself.

Long-standing models propose that plant growth responses to light or gravity are mediated by asymmetric distribution of the phytohormone auxin1 3. Physiological studies implicated a specific transport system that relocates auxin laterally, thereby effecting differential growth4; however, neither the molecular components of this system nor the cellular mechanism of auxin redistribution on light or gravity perception have been identified. Here, we show that auxin accumulates asymmetrically during differential growth in an efflux-dependent manner. Mutations in the Arabidopsis gene PIN3, a regulator of auxin efflux, alter differential growth. PIN3 is expressed in gravity-sensing tissues, with PIN3 protein accumulating predominantly at the lateral cell surface. PIN3 localizes to the plasma membrane and to vesicles that cycle in an actin-dependent manner. In the root columella, PIN3 is positioned symmetrically at the plasma membrane but rapidly relocalizes laterally on gravity stimulation. Our data indicate that PIN3 is a component of the lateral auxin transport system regulating tropic growth. In addition, actin-dependent relocalization of PIN3 in response to gravity provides a mechanism for redirecting auxin flux to trigger asymmetric growth.

Applying the method of pyrolysis coupled with gas chromatography (PYR-GC) the content of endogenous acetylcholine (ACh) was investigated in the extracts obtained from tomato (Lycopersicon esculentum Mill.). Seven-day-old seedlings of wild type (WT) and phytochrome mutants au (aurea), hp (high pigment), fri (far-red light insensitive) and tri (temporarily red light insensitive) were studied. In the analyzed material the presence of choline and acetylcholine was discovered. The highest content of ACh (381 mmole/g of fresh weight) was found in tomato cotyledons, whereas the lowest amount (162 nmole/g of fresh weight) in roots. The level of ACh in the plants grown under the continuous light was higher than in etiolated ones. However, no considerable differences in the concentrations of ACh in au and tri seedlings grown under the continuous light and in darkness were observed. The irradiation of etiolated seedlings of wild type with red light was accompanied by the increase of endogenous level of ACh. The pulse of far-red light applied directly after red light reversed this stimulating effect. A similar effect of both light wavelengths on the content of ACh was also found in the case of the tri mutant. On the other hand, in the case offi-i mutant, pulse of red light caused the drop in the content of ACh, whereas far-red applied after red light caused visible increase in the level of the investigated substance. In tissues of au mutant no effect of red and far-red lights on the concentration of ACh was established.