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tom 75
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nr Supl.
EN
BACKGROUND AND AIMS: Perineuronal nets (PNNs) are complex structures of the nervous system extracellular matrix, composed of hyaluronic acid and chondroitin sulfate proteoglycans. PNNs surround mostly the subset of parvalbumin-expressing interneurons by enwrapping their cell body and proximal dendrites. Their presence stabilizes existing synapses and limits neuronal plasticity. Mechanisms that regulate PNNs expression remain unclear. Changes in PNNs expression are observed in perilesional area after photothrombosis and can be considered an attempt to create conditions favorable for synaptic remodeling. We hypothesize that they may result from the activity of endogenous glycolytic enzymes. METHODS: In the present study, employing quantitative RT-qPCR, we analyzed the expression of genes coding for hyaluronic acid synthesizing and degrading enzymes in cortical region of the perilesional area at 1 h, 24 h and 7 days after photothrombotic stroke. RESULTS: Analysis revealed substantial increase in hyaluronidase 1 (HYAL1) expression level in comparison to homotopic contralateral cortical region and control animals. The rise was recognized at 24 h after stroke and maintained up to 7 days after stroke. No change in expression level of HYAL2 was detected. While 24 h after photothrombosis the elevation in hyaluronic acid synthase 2 (HAS2) expression level was observed, the decrease in HAS3 expression level occurred. The expression level of HAS1 maintained unchanged after stroke. CONCLUSIONS: The obtained data indicate photothrombotic stroke-evoked modification of hyaluronic acid component of PNNs in perilesional area. The results show parallel processes of degradation and synthesis at 24 h, which may exert different effects on neuronal plasticity.  This work was supported by NCN grant 2012/05/B/NZ3/00851.
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nr 4
EN
Over the last twenty years chondroitin sulfate (CS) has become a focus of interest of neuroscience due to its indubitable role in shaping axonal growth, synaptic plasticity and glial scar forming. Various patterns of sulfation give rise to various CS molecules with different properties that are capable of interactions with a plethora of molecules, including growth factors, receptors and guidance molecules. The involvement of CS chains has been implicated in visual critical period regulation, memory formation, spinal cord regeneration. As part of proteoglycan molecules, they are widely expressed in the central nervous system, however, little is known about the enzymatic machinery responsible for CS synthesis and degradation. In this review we attempt to extract and collect the available information concerning the expression and function of enzymes of CS metabolism in the brain.
PL
Artykuł podejmuje problematykę logistyki zwrotnej jako instrumentu przewagi konkurencyjności w przedsiębiorstwach. Przedstawiono w nim czym zajmuje się logistyka zwrotów oraz jaki ma ona wpływ w poszczególnych gałęziach w przedsiębiorstwie. Omawiane są także elementy logistyki zwrotnej tworzące przewagę konkurencyjną. Przeanalizowano również temat efektywności ekonomicznej i ekologicznej logistyki zwrotnej w przedsiębiorstwie przy użyciu wskaźników pomiaru dla działań zwiększających efektywność surowcową dzięki logistyce odzysku.
EN
The article deals with the problem of reverse logistics as an instrument of competitive advantage in enterprises. It presents what logistics deals with and what impact it has in particular branches in the enterprise. The elements of reverse logistics that create a competitive advantage are also discussed. The subject of economic efficiency and ecological return logistics in the enterprise was also analyzed using measurement indicators for measures increasing resource efficiency thanks to recovery logistics.
EN
The barrel and visual cortices are primary model systems to study cortical plasticity. The ability to undergo experience dependent plastic changes depends on brain region, cortical layers, pattern of activity and is altered during development. For instance in mice, a critical period for barrels formation occurs during the fi rst postnatal days whereas in the visual cortex a critical period for ocular dominance plasticity ends about one month after birth. It has been suggested that formation of perineuronal nets (PNNs) during postnatal development may limit cortical plasticity. The aim of this study was to compare developmental patterns of distribution and composition of PNNs in the visual and somatosensory cortex of mice. For this purpose we used monoclonal antibody against chondroitin sulfate proteoglycans to visualized aggrecan (a major component of PNNs) and Wisteria fl oribunda agglutinin (WFA), which selectively recognizes N-acetylo-galactosamine residues within PNNs. At all time points examined in both cortices the highest density (cells/mm2 ) of WFA stained cells occurred in the layer IV. In the barrel cortex, WFA staining fi rst appeared at P10 whereas in the visual cortex WFA stained cells were seen not before P20. In both cortices, the adult like pattern was evident by P30. A composition of PNNs differed between the visual and barrel cortex. Number of aggrecan expressing cells was signifi cantly higher in the visual cortex than in the barrel cortex. Moreover, in the visual cortex aggrecan expressing cells were seen earlier during development than WFA staining. These data seemed to support a view that PNNs are involved in determination of specifi c critical period.
EN
The distribution and density of cells enwrapped with perineuronal nets (PNs) were examined in the neocortex after unilateral photothrombotic stroke. After different survival times PNs was visualized using Wisteria fl oribunda aglutinin (WFA) staining in the infarct core, peri-infarct and remote cortical areas. Sham operated rats and contralateral hemisphere to the stroke site from experimental rats served as controls. In the infarct core, 4 h after stroke only few cells enwrapped with PNs could be detected and none of numerous dying cells present showed PNs, as revealed by double staining (WFA and FJ-C). No cells with PNs were found 24 h after stroke. In the peri-infarct area, dramatic loss of PNs-enwrapped cells occurred (96%) as compared with the contralateral site, and such cells were almost absent after 24 h. However, 30 days after stroke, a signifi cant number of cells with PNs reappeared. In remote cortical areas, 4h after stroke a reduction in the number of cells with PNs was observed. After 24 h the loss of PNs-enwrapped cells was profound (63%) in comparison to intact hemisphere. However, 7d after stroke complete restoration of the number of cells enwrapped with PNs took place. The density of cells with PNs was similar to that found in the contralateral site and in sham operated rats. These results showed the wide spreading and transient effect of photothrombosis on PNs in remote cortical areas. Supported by MNiSW Grant N3030300832/0474 and statutory funds.
PL
Artykuł podejmuje problematykę efektywności proekologicznych aspektów logistyki zwrotnej w przedsiębiorstwie produkcyjnym. Celem artykułu jest przedstawienie głównych aspektów proekologicznych logistyki zwrotnej, jej genezę oraz sprawne i efektywne zagospodarowanie odpadów. Przedstawiono w nim uregulowania prawne dotyczące właściwego postępowania z odpadami oraz ich dalsze zagospodarowanie. Zostały przedstawione opisy aspektów i narzędzi logistyki zwrotnej stosowanych w przedsiębiorstwie produkcyjnym. Poruszono również temat efektywności stosowania logistyki zwrotnej oraz sposoby jej pomiaru i wartościowania skutków ekonomicznych i pozaekonomicznych. Przedstawione zostały także, korzyści wynikające z odpowiednio zarządzanego zwrotnego łańcucha dostaw.
EN
The paper discusses the issue of the efficiency of pro-ecological aspects of reverse logistics in a manufacturing company. The aim of the article is to present major pro-ecological aspects of reverse logistics, its origins and the role in efficient waste management. Legal regulations concerning waste management are analyzed. Description of selected aspects and tools of reverse logistics in a manufacturing company are presented. Efficiency of the application of reverse logistics as well as its measurement and evaluation of economic and extra-economic effects are discussed. Benefits resulting from appropriate management of reverse supply chain are presented.
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