Významným fyziologickým parametrem živých buněk i řady jejich organel je membránový potenciál. K jeho sledování se často používá fluorescenčních sond, které se akumulují uvnitř buněk až do vyrovnání jejich intra- a extracelulárních elektrochemických potenciálů. Obsahem tohoto článku je přehled optických metod sloužících k tomuto účelu, jenž zahrnuje spektrofluometrii, proudovou cytometrii a konfokální mikroskopii a je prezentován jako průřez aktivitami biofyzikálního oddělení Fyzikálního ústavu UK na Matematicko-fyzikální fakultě UK., Jaromír Plášek, Dana Gášková., and Obsahuje seznam literatury
Patients treated for knee disorders were included in this study. They were examined clinically (Lequesne and Tegner scores) and by standard X-ray investigation. Patients underwent a surgical procedure, either arthroscopy or knee replacement. At the initial phase of surgery, a sample of cartilage was taken for laboratory examination. Progression of the disorder and the clinical examination was correlated with the actual state of the cartilage using a novel fluorescence approach. The intrinsic fluorescence of cartilages was shown as a suitable and sensitive method for detection of the actual state of cartilages because the correlation with X-ray examination and clinical status was found. Intrinsic fluorescence properties of cartilages from patients with chondropathy and osteoarthritis were described and found to be age-dependent. We also observed a higher concentration of advanced glycation end products due to inflammatory and/or degenerative processes in the cartilage. In addition, acute pathological changes due to diseases such as meniscal lesions or anterior cruciate ligament rupture caused a significant increase of formation of advanced glycation end products even in the group of young patients. In fact, such an observation could be crucial and important for the detection of knee conditions suspected of early meniscal and/or ACL lesions especially among young patients., M. Handl, E. Filová, M. Kubala, Z. Lánský, L. Koláčná, J. Vorlíček, T. Trč, M. Pach, E. Amler., and Obsahuje bibliografii a bibliografické odkazy
Cellular cholesterol plays fundamental and diverse roles in many biological processes and affects the pathology of various diseases. Comprehensive and detailed understanding of the cellular functions and characteristics of cholesterol requires visualization of its subcellular distribution, which can be achieved by fluorescence microscopy. Many attempts have been made to develop fluorescent cholesterol reporters, but so far, none of them seems to be ideal for studying all aspects of cholesterol management. To meet the requirements for the right probe remains a great challenge, and progress in this field continues. The main objective of this review is to not only present the current state of the art, but also critically evaluate the applicability of individual probes and for what purpose they can be used to obtain relevant data. Hence, the data obtained with different probes might provide complementary information to build an integrated picture about the cellular cholesterol. and Corresponding author: Jarmila Králová
Aluminofluoride complexes (AlFx) form spontaneously in aqueous solutions containing fluoride and traces of aluminum ions and appear to act as phosphate analogs. These complexes have become widely utilized in laboratory investigations of various guanine nucleotide-binding proteins. Reflecting on many laboratory studies, a new mechanism of fluoride and aluminum action on the cellular level is being suggested. The long-term synergistic effects of these ions in living environment and their hidden danger for human health are not yet fully recognized., A. Strunecká, O. Strunecký, J. Patočka., and Obsahuje bibliografii
Jerry Fodor’s causal theory of content is a well-known naturalistic attempt purporting to show that Brentano was wrong in supposing that physical states cannot possess meaning and reference. Fodor’s theory contains two crucial elements: one is a notion of ''asymmetric dependence between nomic relations'', and the other is an assumption about the nature of the ''causally operative properties'' involved in the causation of mental tokens. Having dealt elsewhere with the problems Fodor’s notion of asymmetric dependence poses, we show in this paper a difficulty with the other element of his theory concerning what kinds of properties are the causally operative ones in the tokenings of a semantic symbol in the brain of a perceiver. After presenting this difficulty, we examine three possible responses a Fodorian might make to our criticism., Kauzální teorie obsahu Jerryho Fodora je známým naturalistickým pokusem, který ukazuje, že Brentano se mýlil v domněnce, že fyzické stavy nemohou mít smysl a odkaz. Fodorova teorie obsahuje dva klíčové elementy: jeden je představa o ''asymetrické závislosti mezi nomic vztahy'', a jiný je předpoklad o povaze ''kauzálně operativních vlastností'' zahrnutý v příčině duševních tokenů. Když jsme se zabývali problémy s Fodorovým pojetím asymetrické závislosti, ukázali jsme v tomto článku problém s dalším prvkem jeho teorie týkajícím se toho, jaké vlastnosti jsou kauzálně operativní v tokenech sémantického symbolu v mozku vnímatele. . Poté, co představíme tento problém, zkoumáme tři možné reakce, které by Fodorian mohl učinit pro naši kritiku., and Tevfik Aytekin ; Erdinç Sayan
The 10 Biblical songs, a complete cycle, are based on ten Psalms, freely built by Dvorak from excerpts of original texts. The whole, based especially on the dialectic of faith and fright, caused the composer to set to music some words and sentences in a special way. Chosen verses, omitted verses, metrics, nuances, tonal constructions, but also linguistic adjustments – for English or German translations – and multiplication of the versions (with piano or with orchestra) put in light a progression going twice from pain to praise, from entreaty to confidence via fear. Beyond nostalgic vague memories of the native country and the loneliness in foreign countries, is a progression which allows a better understanding of Dvorak’s religious renewal during his stay in America.
The works of fiction of K. B. Vaid (born in 1927) question the relationship between postmodern literature and religiosity. The novel Dard lā davā (1975), a long non-referential monologue, close to the Beckettian "absurd" parallels the concepts of exile and the mystical quest, where the notions of "pain:, "doubt", "alienation" and "separation" are equally convoked. Nevertheless, the lack of "faith", as claimed by the author, finds its "raison d´être" in his refusal to employ definite religous categories, such as orthodoxy, the polarisation of Islam and Hinduism, and the divine authority itself when blasphemy is exploited. The religious discourse, the author insists, should be human, secular, mixed and polyphonic. The purpose of this paper is, primarily, to bring to liht the way Vaid´s most unreferential narratives continue to draw their metaphysical discourse from indigenous sources. Subsequently, from this metaphysical and mystical discourse, I will investigate the way the author elaborates a new form of "faith", non subservient to the constraints often conveyed to be orthodox religious discourses. What the author calls "mystical agnosticism" is not just a matter of the re-appropriation of an indigenous discourse, but also a matter of the hybridization of sources.
Final focusation of high power laser systems is usually utilized by an off-axis parabolic mirror. However, for various reasons it can be advantageous to use axial spherical mirror. Therefore, the beam needs to be extracted from the system for example by the central hole in the planar mirror. Submitted paper demonstrates especially power transmission aspects of such systems and also shows the influence of surface irregularities on the quality of beam focused through the mirror hole. The following study is conducted in Wyrowski VirtualLab Fusion. and Fokusace svazků vysokého výkonu se zpravidla provádí s využitím mimoosového (off-axis) parabolického zrcadla. Z různých důvodů může být cílem náhrada mimoosového parabolického zrcadla osovým sférickým zrcadlem. V takovém případě je nutné jiným způsobem vyvést laserový svazek ven z optického systému. Jedním z nich může být centrální díra v planárním zrcadle. Prezentovaný článek se zaměřuje zejména na přenos energie svazku v systému s centrální dírou a také na vliv povrchových nepravidelností zrcadel v systému na výslednou kvalitu fokusovaného svazku. Studie je provedena s využitím kombinace softwaru Wyrowski VirtualLab Fusion a Zemax OpticStudio.
Jaromír Chalupský, Tomáš Burian, Michael Grisham, Věra Hájková, Scott Heinbuch, Krzysztof Jakubczak, Libor Juha, Tomáš Mocek, Peter Pira, Jiří Polan, Jorge J. Rocca, Bedřich Rus, Jaroslav Sobota, Luděk Vyšín. and Obsahuje seznam literatury
Photosynthetic organs are often characterized by anthocyanins being accumulated either in the epidermal or in the mesophyll cells making these tissues to turn reddish-brown in colour. It has been hypothesized that these pigments protect underlying chloroplasts from light-stress because they absorb photons of the photosynthetically active waveband. However, the photoprotective role of anthocyanins has not been undoubtedly shown on a broad range of species. In this study, green and anthocyanic areas of leaves of Pelargonium × hortorum, the latter possessing variable levels of anthocyanins, were compared using pigment analysis and pulse amplitude modulated in vivo chlorophyll (Chl) fluorescence. Quenching analysis of the induction and dark relaxation curves of slow Chl fluorescence kinetics showed that at photoinhibitory conditions [by applying above-saturation light intensity of 1,600 μmol(quantum) m-2 s-1 white light at low (4°C) temperature], anthocyanic areas were at least equally sensitive to photoinhibition as green leaf areas. In fact, the level of photoinhibition tended to be proportional to the level of anthocyanin accumulation suggesting that this characteristic was indicative of the photoinhibitory risk. The results of the present study clearly show that anthocyanins in leaf areas of Pelargonium do not afford a photoprotective advantage., G. Liakopoulos, I. Spanorigas., and Obsahuje bibliografii