130 research outputs found
Parallelized STED fluorescence nanoscopy.
No full textWe introduce a parallelized STED microscope featuring m = 4 pairs of scanning excitation and STED beams, providing m-fold increased imaging speed of a given sample area, while maintaining basically all of the advantages of single beam scanning. Requiring only a single laser source and fiber input, the setup is inherently aligned both spatially and temporally. Given enough laser power, the design is readily scalable to higher degrees of parallelization m
Fluoreszenznanoskopie einzelner DNA-Moleküle mit Fluoreszenzverhinderung durch stimulierte Emission (STED)
No full textScharfe Aufnahmen: STED-Nanoskopie (STED=stimulierte Fluoreszenzverhinderung) von einzelnen DNA-Strängen visualisiert Strukturen mit einer 5- bis 6fach höheren Auflösung als konfokale Mikroskopie (Konf), wie aus dem linken bzw. rechten Bild ersichtlich ist. Die STED-Technik enthüllt Strukturen der Größenordnung der DNA-Persistenzlänge (ca. 50 nm), ohne dabei in maßgeblicher Weise Photoschäden wie Bleichen oder DNA-Bruch zu verursachen
Tissue multicolor STED nanoscopy of presynaptic proteins in the calyx of held
No full textThe calyx of Held, a large glutamatergic terminal in the mammalian auditory brainstem has been extensively employed to study presynaptic structure and function in the central nervous system. Nevertheless, the nanoarchitecture of presynaptic proteins and subcellular components in the calyx terminal and its relation to functional properties of synaptic transmission is only poorly understood. Here, we use stimulated emission depletion (STED) nanoscopy of calyces in thin sections of aldehyde-fixed rat brain tissue to visualize immuno-labeled synaptic proteins including VGluT1, synaptophysin, Rab3A and synapsin with a lateral resolution of approximately 40 nm. Excitation multiplexing of suitable fluorescent dyes deciphered the spatial arrangement of the presynaptic phospho-protein synapsin relative to synaptic vesicles labeled with anti-VGluT1. Both predominantly occupied the same focal volume, yet may exist in exclusive domains containing either VGluT1 or synapsin immunoreactivity. While the latter have been observed with diffraction-limited fluorescence microscopy, STED microscopy for the first time revealed VGluT1-positive domains lacking synapsins. This observation supports the hypothesis that molecularly and structurally distinct synaptic vesicle pools operate in presynaptic nerve terminals
Fluorescence nanoscopy of single DNA molecules by using stimulated emission depletion (STED).
No full textClearing the haze: Stimulated emission depletion (STED) nanoscopy on single DNA strands reveals details with an up to five- to sixfold improved resolution over confocal microscopy (see images). Thus STED nanoscopy allows features to be distinguished down to the persistence length of DNA (ca. 50 nm) without promoting any significant additional photodamage, such as photobleaching or photonicking
Teofania stworzenia w myśli Hildegardy z Bingen
No full textThe article attempts to reconstruct the elements of theology, anthropology, and ethic in the thought of Hildegard of Bingen on the basis of Hildegard’s visionary trilogy. Hildegard of Bingen was one of the dominating characters in the spiritual and social life of the 12th century. Her visionary images and symbols cover the entire world of her times and offer unusual insights into her conception of man and the world around him. The author concentrates on the cosmological and anthropological strands of her thought, trying to find a key to her symbolism. In Hildegard’s thought the sacramental character of the universe is discovered and celebrated.Zeszyty Naukowe TDU
Image of Holy Hildegard of Bingen in Contemporary Culture
No full textImage of Holy Hildegard of Bingen in Contemporary Culture
The article St. Hildegard of Bingen in Contemporary Culture was based on fragments of Licence Work.: St.Hildegard of Bingen – medival “feminist” and contemporary doctor of Church. The author concentrates on great interest of Saint Hildegard – the most interesting and best known monk of medieval ages. Saint Hildegard is a authority and inspiration for many different societes generating discussions. This work tries to answer questions on manipulation and use of Hildegard by contemporary culture. It also underlines stereotypes of thinking about medival ages and position of women in Church
Obraz św. Hildegardy z Bingen w polskiej kulturze współczesnej
No full textThe article St. Hildegard of Bingen in Contemporary Culture was based on fragments of Licence Work.: St.Hildegard of Bingen – medival “feminist” and contemporary doctor of Church. The author concentrates on great interest of Saint Hildegard – the most interesting and best known monk of medieval ages. Saint Hildegard is a authority and inspiration for many different societes generating discussions. This work tries to answer questions on manipulation and use of Hildegard by contemporary culture. It also underlines stereotypes of thinking about medival ages and position of women in Church.The article St. Hildegard of Bingen in Contemporary Culture was based on fragments of Licence Work.: St.Hildegard of Bingen – medival “feminist” and contemporary doctor of Church. The author concentrates on great interest of Saint Hildegard – the most interesting and best known monk of medieval ages. Saint Hildegard is a authority and inspiration for many different societes generating discussions. This work tries to answer questions on manipulation and use of Hildegard by contemporary culture. It also underlines stereotypes of thinking about medival ages and position of women in Church
Chrysomya putoria, a putative vector of diarrheal diseases.
No full textBACKGROUND: Chrysomya spp are common blowflies in Africa, Asia and parts of South America and some species can reproduce in prodigious numbers in pit latrines. Because of their strong association with human feces and their synanthropic nature, we examined whether these flies are likely to be vectors of diarrheal pathogens. METHODOLOGY/PRINCIPAL FINDINGS: Flies were sampled using exit traps placed over the drop holes of latrines in Gambian villages. Odor-baited fly traps were used to determine the relative attractiveness of different breeding and feeding media. The presence of bacteria on flies was confirmed by culture and bacterial DNA identified using PCR. A median of 7.00 flies/latrine/day (IQR = 0.0-25.25) was collected, of which 95% were Chrysomya spp, and of these nearly all were Chrysomya putoria (99%). More flies were collected from traps with feces from young children (median = 3.0, IQR = 1.75-10.75) and dogs (median = 1.50, IQR = 0.0-13.25) than from herbivores (median = 0.0, IQR = 0.0-0.0; goat, horse, cow and calf; p<0.001). Flies were strongly attracted to raw meat (median = 44.5, IQR = 26.25-143.00) compared with fish (median = 0.0, IQR = 0.0-19.75, ns), cooked and uncooked rice, and mangoes (median = 0.0, IQR = 0.0-0.0; p<0.001). Escherichia coli were cultured from the surface of 21% (15/72 agar plates) of Chrysomya spp and 10% of these were enterotoxigenic. Enteroaggregative E. coli were identified by PCR in 2% of homogenized Chrysomya spp, Shigella spp in 1.4% and Salmonella spp in 0.6% of samples. CONCLUSIONS/SIGNIFICANCE: The large numbers of C. putoria that can emerge from pit latrines, the presence of enteric pathogens on flies, and their strong attraction to raw meat and fish suggests these flies may be common vectors of diarrheal diseases in Africa
Parallelised STED nanoscopy
No full textOptische Nanoskopie hat sich als wertvolles Instrument für die Molekularbiologeentwickelt. Diese Methoden sind nicht mehr durch die Beugung des Lichtes begrenzt und führen zu neuen Herausforderungen. Das dafür erforderliche Schalten des molekularen Signals macht eine zeitlich sequentielle Signalaufnahme erforderlich und führt zu längeren Aufnahmezeiten mit steigender Auflösung. Um die Gesamtaufnahmezeit des Bildfeldes zu reduzieren und damit die Attraktivität der hochauflösenden optischen Methoden für die Biologie zu erhöhen ist eine Parallelisierung des Bildfeldes essenziell. Diese Arbeit befasst sich mit den fundamentalen Grenzen der parallelisierten Nanoskopie und beinhaltet die erste experimentelle Ausführung von parallelisierter Koordinaten-definierter Nanoskopie mit Fluoreszenzverhinderung durch stimulierte Emission (STED). Eine verlustfreie vierfache Parallelisierung wird durch polarisierende Strahlteiler und ein chromatisches segmentiertes Wellenplättchen, welches als formgestaltendes Element fungiert, ermöglicht. Eine gemeinsame Faserlichtquelle gewährleistet dass alle Laserstrahlen sowohl räumlich als auch zeitlich überlagert sind. Die zeitreduzierende Eigenschaft von Parallelisierung wurde nachgewiesen. Diese Arbeit führt außerdem eine neue Detektionsmethode in die Nanoskopie ein, welche die koinzidenten Photonen pro Laserzyklus detektiert.Der Effekt des Photonenantibunching von fluoreszenten Molekülen ermöglichtes die Anzahl von gleichzeitig angeregten Molekülen aus der Photonenstatistikheraus zu bestimmen. Dies erlaubt es Koordinaten-definierten Nanoskopiemethoden, wie STED, die Anzahl der fluoreszenten Molekülenim Fokus zu zählen
Maturation-Dependent HIV-1 Surface Protein Redistribution Revealed by Fluorescence Nanoscopy
No full textHuman immunodeficiency virus type 1 (HIV-1) buds from the cell as an immature particle requiring subsequent proteolysis of the main structural polyprotein Gag for morphological maturation and infectivity. Visualization of the viral envelope (Env) glycoprotein distribution on the surface of individual HIV-1 particles with stimulated emission depletion (STED) superresolution fluorescence microscopy revealed maturation-induced clustering of Env proteins that depended on the Gag-interacting Env tail. Correlation of Env surface clustering with the viral entry efficiency revealed coupling between the viral interior and exterior: Rearrangements of the inner protein lattice facilitated the alteration of the virus surface in preparation for productive entry. We propose that Gag proteolysis-dependent clustering of the sparse Env trimers on the viral surface may be an essential aspect of HIV-1 maturation
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