Modulation of synaptic transmission in the development of painful states

Má práce uvádí do problematiky nociceptivní signalizace a procesů zapojených do vzniku a formování neuropatické bolesti. Věnuje se studiu mechanizmů nociceptivního synaptického přenosu na míšní úrovni a možnostem jeho modulace paclitaxelem, chemoterapeutikem navozujícím neuropatické změny. Pozornost je věnována především možnosti zapojení aktivity gliových buněk při nežádoucím působení tohoto léčiva. Tato hypotéza využívá důkazů funkčního spojení aktivity Toll-like 4 receptorů s aktivitou TRPV1 receptorů důležitých pro vnímání různých chemických a tepelných senzorických podnětů a také v nociceptivním synaptickém přenosu. K blokaci aktivace mikroglií bylo využito antibiotikum minocyklin zamezující vzniku neuroinflamace. Praktická část potom sleduje a porovnává vliv použitých látek na model procesu tachyfylaxe používaný pro sledování změn nociceptivní signalizace vlivem snižování aktivity TRPV1 receptorů. Práce ke zkoumání tohoto jevu využívá elektrofyziologické snímání aktivity miniaturních excitačních postsynaptických proudů neuronů I. a II. Rexedovy laminy zadního míšního rohu. Výsledky měření ukazují, že inkubace míšních řezů v minocyklinu in vitro potlačuje akutní působení paclitaxelu, Toto potlačení aktivace mikroglií naznačuje, že se gliové buňky svou aktivitou podílejí na modulacích...My thesis introduces the topic of nociceptive signalisation and processes involved in the formation and spreading of neuropathic pain. This study focuses on the mechanisms of nociceptive synaptic transmission mechanisms in the level of spinal dorsal horn and its modulation by paclitaxel, a chemotherapeutic drug inducing neuropathic changes. The attention is put especially on the possibility of glial activity participation in paclitaxel side effects. This idea stems from the existing hypothesis of the functional connection between TLR4 and TRPV1 receptor activity. TRPV1 is well known for its participation in chemical, thermal and nociceptive sensory transmission. Minocycline antibiotic is considered as an inhibitor of microglial activation therefore it was used for blocking neuroinflammation. The experimental part is comparing an impact of substances applied to the model of tachyphylaxis used for monitoring of nociceptive transmission changes according to decreasing activity of TRPV1 receptors. Electrophysiological recording of miniature excitatory postsynaptic currents from neurons in the Rexed laminae I. and II. of spinal dorsal horn was used. The results of my measurements show that minocycline is able to suppress acute effects of paclitaxel application in vitro if the spinal slice is incubated...Katedra fyziologieDepartment of PhysiologyPřírodovědecká fakultaFaculty of Scienc

Noble Metal Nanoparticles Prepared by Metal Sputtering into Glycerol and their Grafting to Polymer Surface

This chapter summarizes the basic information about elementary characteristics and technology of preparation of noble metal nanoparticles. The introduction gives some basic information on the history of development in this area, especially in terms of dimensionality of metal nanostructures and their possible applications.The first subsection is devoted to the preparation and characterization of Au, Ag, Pt, and Pd nanoparticles (NPs), which were synthesized by direct metal sputtering in liquid propane-1,2,3,-triole (glycerol). This method provides an interesting alternative to time-consuming, wet-based chemical synthesis techniques. Moreover, the suggested technique allows targeted variation of metal nanoparticle size, which is demonstrated in detail in case of AuNPs by variation of capturing media temperature. Nanoparticle size and shape were studied by transmission electron microscopy and dynamic light scattering. Optical properties of nanoparticle solution were determined by measuring its UV–Vis spectra. Concentration of metal nanoparticles in prepared solutions was determined by atomic absorption spectroscopy. Antibacterial properties were tested against two common pollutants (Escherichia coli, a Gram-negative bacteria, and Staphylococcus epidermidis, a Gram-positive bacteria). In the presence of Ag nanoparticles, the growth of E. coli and S. epidermidis was completely inhibited after 24 h. Any growth inhibition of E. coli was observed neither in the presence of “smaller” (4–6 nm, AuNP4–6) nor “bigger” (9–12 nm, AuNP8–12) AuNPs during the whole examination period. AuNP4–6, but not AuNP8–12, was able to inhibit the growth of. S epidermidis. We also observed significant difference in biological activities of Pt and PdNPs. More specifically, PdNPs exhibited considerable inhibitory potential against both E. coli and S. epidermidis, which was in contrast to ineffective PtNPs. Our results indicate that Ag, Pd, and partially AuNPs have high potential to combat both Gram-positive and Gram-negative bacterial strains.The second subsection describes the effort to anchor metal nanoparticles onto polyethyleneterephthalate (PET) carrier. Two different procedures of grafting of polymeric carrier, activated by plasma treatment, with Au and AgNPs are described. In the first procedure, the PET foil was grafted with biphenyl-4,4’-dithiol (BPD) and subsequently with Au and AgNPs. In the second one, the PET foil was grafted with Au and AgNPs previously coated by the same BPD. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and electrokinetic analysis were used for characterization of the polymer surface at different modification steps. Au and AgNPs were characterized by UV–Vis spectroscopy. In case of both types of nanoparticles, the first procedure was found to be more effective. It was proved that the BPD was chemically bonded to the surface of the plasma-activated PET and it mediates subsequent grafting of the AuNPs

Issues Of Group Cohesion In Sport Psychology

Článek se zabývá problematikou skupinové koheze, a to jak z obecného sociálně psychologického pohledu, tak z pohledu psychologie sportu, kde jsou otázky skupinové koheze často spojovány se skupinovým výkonem. Je věnována pozornost zejména teoretickým přístupům k problematice skupinové koheze, kde se ukazuje rozmanitost chápání a definování koheze jako skupinového jevu. Autoři se také zabývají důležitostí koheze v oblasti sportu, kdy zejména kolektivní sporty vytvářejí nejvhodnější předpoklady pro působení koheze jako faktoru modifikujícího výkon sportovních družstev. V článku jsou prezentovány i možnosti diagnostiky koheze využitelné ve sportovní praxi a je provedeno srovnání výsledků studií různých autorů používajících uvedené metody v oblasti sportu. V závěru jsou naznačeny další možnosti zkoumání tohoto jevu, který nebývá častým předmětem zkoumání v našich podmínkách.The article presents a review of research on group cohesion; an important social-psychological construct especially relevant to sport psychology where group cohesion is often considered as a crucial factor in the performance of sport teams. First, the article focuses on theoretical approaches to a delimitation of group cohesion as a diverse construct which has been defined in various ways. The article also shows the importance of cohesion and its dynamics in the field of sport where in particular the performance in team sports, which seems to be directly related to the relative level of group cohesion. Furthermore, the article presents diagnostic possibilities of group cohesion useful in coaching practice and compares the results of various research applications of these methods in the field of sport. Finally, the authors suggest possible directions in further research of this construct which has not been sufficiently studied in the Czech context

Psychosocial Aspects Of A Risk Behaviour In Sporting Children

V této přehledové studii se zabýváme některými rizikovými faktory ve sportu dětí a mládeže. Na příkladech výzkumů zabývajících se dopingem, násilím a fair play ukazujeme, jak mohou normy vrcholového sportu zdůrazňující soutěžní výsledky, maximální výkon a vítězství za každou cenu přispívat k rizikovému chování sportujících dětí a mládeže, jako je například zneužívání dopingu, nepřiměřené agresivitě či porušování pravidel a zásad fair play. Toto rizikové chování pak nezůstává omezeno pouze na kontext sportu, ale může se přenášet i do běžného života mimo sport.In this overview study, we focus on some possible risk factors in child and youth sport. In the overview of contemporary research focusing on doping, violence and fair play, we show how the norms of contemporary competitive sport emphasise results, maximal performance and victory at all costs, may support a behaviour risk in sporting children and youth, such as doping, abuse, inappropriate aggression, rule breaking and fair play. It seems that this risk behaviour is not limited only to the context of sport but translates also in the life outside sport

Argon plasma irradiation of polypropylene

a b s t r a c t Polypropylene samples were exposed to argon plasma discharge and the changes of the PP surface properties were studied by different methods. Surface wettability was derived from contact angle measured by standard goniometry and chemical structure of the plasma modified PP was studied using X-ray photoelectron spectroscopy (XPS) and by Rutherford backscattering spectroscopy (RBS), surface morphology and roughness of samples using AFM. Zeta potential of pristine and modified PP was determined with the SurPASS. The presence of incorporated oxygen in the PP surface layer, about 60 nm thick, was observed in RBS spectra. Oxygen concentration is a decreasing function of the depth. With progressing aging time the oxygen concentration on the PP surface decreases. Plasma treatment results in a rapid decrease of the contact angle, which increases again with increasing aging time. In XPS measurement the oxygen containing structures, created by the plasma treatment, were found on the very surface of the modified PP and the zeta potential being changed too. The significant difference in zeta potential between pristine and plasma treated PP clearly indicates that the plasma treatment leads to a more hydrophilic PP surface

"Soft and rigid" dithiols and Au nanoparticles grafting on plasma-treated polyethyleneterephthalate

Surface of polyethyleneterephthalate (PET) was modified by plasma discharge and subsequently grafted with dithiols (1, 2-ethanedithiol (ED) or 4, 4'-biphenyldithiol) to create the thiol (-SH) groups on polymer surface. This "short" dithiols are expected to be fixed via one of -SH groups to radicals created by the plasma treatment on the PET surface. "Free" -SH groups are allowed to interact with Au nanoparticles. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and electrokinetic analysis (EA, zeta potential) were used for the characterization of surface chemistry of the modified PET. Surface morphology and roughness of the modified PET were studied by atomic force microscopy (AFM). The results from XPS, FTIR, EA and AFM show that the Au nanoparticles are grafted on the modified surface only in the case of biphenyldithiol pretreatment. The possible explanation is that the "flexible" molecule of ethanedithiol is bounded to the activated PET surface with both -SH groups. On the contrary, the "rigid" molecule of biphenyldithiol is bounded via only one -SH group to the modified PET surface and the second one remains "free" for the consecutive chemical reaction with Au nanoparticle. The gold nanoparticles are distributed relatively homogenously over the polymer surface