bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rhodamine Spiroamides for Multicolor Single‐Molecule Switching Fluorescent Nanoscopy
Authors: Belov Vladimir N. , Bossi Mariano L. , Fölling Jonas , Boyarskiy Vadim P. , Hell Stefan W. 
Published: September 2009

AbstractThe design, synthesis, and evaluation of new rhodamine spiroamides are described. These molecules have applications in optical nanoscopy based on random switching of the fluorescent single molecules. The new markers may be used in (co)localization studies of various objects and their (mutual) positions and shape can be determined with a precision of a few tens of nanometers. Multicolor staining, good photoactivation, a large number of emitted photons, and selective chemical binding with amino or thiol groups were achieved due to the presence of various functional groups on the rhodamine spiroamides. Rigidized sulfonated xanthene fragment fused with six‐membered rings, N,N′‐bis(2,2,2‐trifluoroethyl) groups, and a combination of additional double bonds and sulfonic acid groups with simple aliphatic spiroamide residue provide multicolor properties and improve performance of the rhodamine spiroamides in photoactivation and bioconjugation reactions. Having both essential parts of the photoswitchable assembly—the switching and the fluorescent (reporter) groups—combined in one chemical entity make this approach attractive for further development. A series of rhodamine spiroamides is presented along with characterizations of their most relevant properties for application as fluorescent probes in single‐molecule switching and localization microscopy. Optical images with resolutions on the nanometer scale illustrate the potential of the labels in the colocalization of biological objects and the two‐photon activation technique with optical sectioning.
The Incorporation of Indigo Molecules in Sepiolite Tunnels
Authors: Ovarlez Sonia , Giulieri Françoise , Chaze Anne‐Marie , Delamare François , Raya Jesus , Hirschinger Jerome 
Published: September 2009

AbstractEvidence for access of molecules the size of acetone or pyridine to the intracrystalline tunnels of nanofibre clay (sepiolite) has indicated formation of a new type of organic–inorganic nanocomposites. However, the introduction of larger molecules has been a recurring problem. It is now agreed that for indigo, the molecules are located on the external surface and at the ends of the fibres, thus blocking access to internal tunnels. We claim, however, that it is possible for indigo molecules to access the internal channels of sepiolite. FTIR and XRD analyses have provided evidence for folding of the sepiolite structure preheated at high temperature (above 350 °C). By comparison, we have shown that for indigo/sepiolite mixtures treated in the same conditions, no change in the crystalline structure of the sepiolite is observed, and that blue samples, related to Maya blue, with indigo molecules incorporated deeply enough into sepiolite to prevent folding of the tunnels, can be obtained. NMR, FTIR and thermal analysis confirm the interaction of indigo with the water coordinated to magnesium(II) and located inside the internal and external channels of sepiolite. Two other hypotheses are excluded; we show both that zeolitic water is not blocked in the tunnels by indigo, and that if thermal decomposition products of indigo can be formed, they are in a minority.
Angiotensin type‐1 receptor inhibition is neuroprotective to amacrine cells in a rat model of retinopathy of prematurity
Authors: Downie Laura E. , Hatzopoulos Kate M. , Pianta Michael J. , Vingrys Algis J. , Wilkinson‐Berka Jennifer L. , Kalloniatis Michael , Fletcher Erica L. 
Published: September 2009

AbstractRetinopathy of prematurity (ROP) is characterized by deficits in the scotopic pathway, although the cellular locus for these deficits is not clear. Here we examined neurochemical and cellular changes that develop during oxygen‐induced retinopathy, a model of ROP. In addition, we examined whether treatment with the angiotensin II type‐1 receptor inhibitor, valsartan, prevented these changes. Newborn Sprague–Dawley rats were exposed from postnatal day (P) 0 to 11 to 80%:20% O2 (22:2 hr/day) and then room air until P18. Valsartan (40 mg/kg/day) was administered from P12–P18. Pattern recognition analysis of overlapping amino acid profiles was used to provide a statistically robust and spatially complete classification of neural elements for each experimental condition. Classification yielded 12 neuronal theme classes in controls and nine classes following ROP. ROP was associated with a reduction in the number of amacrine and bipolar cell theme classes. The reduction in theme classes was confirmed as true neuronal loss by quantifying anatomical changes and using an apoptotic marker. ROP was associated with shifts in amino acid levels across all neuronal populations except for horizontal cells. A reduction in the density of glycine‐immunoreactive amacrine cells, and particularly parvalbumin‐immunoreactive AII amacrine cells, was observed following ROP. Valsartan treatment during ROP prevented loss of theme classes and loss of AII amacrine cells. This study suggests that deficits in scotopic vision during ROP may be associated with loss of AII amacrine cells. In addition, this study highlights the potential of AT1R blockade in preventing neuronal anomalies in this condition. J. Comp. Neurol. 518:41–63, 2010. © 2009 Wiley‐Liss, Inc.
Synaptic connections of PDF‐immunoreactive lateral neurons projecting to the dorsal protocerebrum of Drosophila melanogaster
Authors: Yasuyama Kouji , Meinertzhagen Ian A. 
Published: September 2009

AbstractRecent studies in Drosophila melanogaster indicate that the neuropeptide pigment‐dispersing factor (PDF) is an important output signal from a set of major clock neurons, s‐LNvs (small ventral lateral neurons), which transmit the circadian phase to subsets of other clock neurons, DNs (dorsal neurons). Both s‐LNvs and DNs have fiber projections to the dorsal protocerebrum of the brain, so that this area is a conspicuous locus for coupling between different subsets of clock neurons. To unravel the neural circuits underlying the fly's circadian rhythms, we examined the detailed subcellular morphology of the PDF‐positive fibers of the s‐LNvs in the dorsal protocerebrum, focusing on their synaptic connections, using preembedding immunoelectron microscopy. To examine the distribution of synapses, we also reconstructed the three‐dimensional morphology of PDF‐positive varicosities from fiber profiles in the dorsal protocerebrum. The varicosities contained large dense‐core vesicles (DCVs), and also numerous small clear vesicles, forming divergent output synapses onto unlabeled neurites. The DCVs apparently dock at nonsynaptic sites, suggesting their nonsynaptic release. In addition, a 3D reconstruction revealed the presence of input synapses onto the PDF‐positive fibers. These were detected less frequently than output sites. These observations suggest that the PDF‐positive clock neurons receive neural inputs directly through synaptic connections in the dorsal protocerebrum, in addition to supplying dual outputs, either synaptic or via paracrine release of the DCV contents, to unidentified target neurons. J. Comp. Neurol. 518:292–304, 2010. © 2009 Wiley‐Liss, Inc.
Quantitative study of the developmental changes in calcium‐permeable AMPA receptor‐expressing neurons in the rat somatosensory cortex
Authors: Hsu Cheng‐I , Wang Tzu‐Chien , Hou Szu‐Yu T. , Chin Ting‐Yu , Chang Yen‐Chung 
Published: September 2009

AbstractThe distribution of cells expressing calcium‐permeable α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptors (CP‐AMPARs) in the somatosensory cortex of rats at different developmental stages was studied using a kainate‐stimulated Co2+‐labeling assay in a quantitative manner. The applicability of this assay for identifying CP‐AMPAR‐expressing cells was first verified using cultured rat cortical neurons by means of fluorescence Ca2+imaging and pharmacological tools. Cells positively identified by the Co2+‐labelinig assay resided primarily in the marginal zone and subplate of young fetuses and became more widely distributed throughout the cortex as the fetus matured. The majority, >80%, of these Co2+‐positive cells were neurons, exhibiting immunoreactivity with the neuronal marker NeuN. The proportion of neurons that were Co2+‐positive increased from ≈25% to ≈60% as the rat fetus grew into adulthood. In contrast, less than 20% of nonneuronal cells were Co2+‐positive. Of the Co2+‐positive neurons, 15%–31% exhibited GABA immunoreactivity and nonpyramidal‐shaped cell bodies; these were presumably GABAergic neurons. Most of the remaining non‐GABAergic/Co2+‐positive neurons had pyramidal‐shaped cell bodies and were presumably excitatory principle neurons. Around 70% of GABAergic neurons in the cortex were Co2+‐positive. Furthermore, in the cortex of neonatal rats the Co2+‐positive neurons were found to be more susceptible to kainate toxicity than the Co2+‐negative cells. The Co2+‐positive neurons in the subplate of neonatal rats were more vulnerable to kainate toxicity than their counterparts in the remaining cortical areas. Together, the widespread distribution and distinct susceptibility to excitotoxicity of CP‐AMPAR‐expressing neurons suggest that they play various important roles in the development and physiology of the rat cerebral cortex. J. Comp. Neurol. 518:75–91, 2010. © 2009 Wiley‐Liss, Inc.
Ikaros‐1 couples cell cycle arrest of late striatal precursors with neurogenesis of enkephalinergic neurons
Authors: Martín‐Ibáñez Raquel , Crespo Empar , Urbán Noelia , Sergent‐Tanguy Solène , Herranz Cristina , Jaumot Montserrat , Valiente Manuel , Long Jason E. , Pineda José Ramón , Andreu Celia , Rubenstein John L.R. , Marín Óscar , Georgopoulos Katia , Mengod Guadalupe , Fariñas Isabel , Bachs Oriol , Alberch Jordi , Canals Josep M. 
Published: September 2009

AbstractDuring central nervous system development, several transcription factors regulate the differentiation of progenitor cells to postmitotic neurons. Here we describe a novel role for Ikaros‐1 in the generation of late‐born striatal neurons. Our results show that Ikaros‐1 is expressed in the boundary of the striatal germinal zone (GZ)/mantle zone (MZ), where it induces cell cycle arrest of neural progenitors by up‐regulation of the cyclin‐dependent kinase inhibitor (CDKi) p21Cip1/Waf1. This effect is coupled with the neuronal differentiation of late precursors, which in turn is critical for the second wave of striatal neurogenesis that gives rise to matrix neurons. Consistently, Ikaros−/− mice had fewer striatal projecting neurons and, in particular, enkephalin (ENK)‐positive neurons. In addition, overexpression of Ikaros‐1 in primary striatal cultures increases the number of calbindin‐ and ENK‐positive neurons. Our results also show that Ikaros‐1 acts downstream of the Dlx family of transcription factors, insofar as its expression is lost in Dlx1/2 double knockout mice. However, we demonstrate that Ikaros‐1 and Ebf‐1 independently regulate the final determination of the two populations of striatal projection neurons of the matrix compartment, ENK‐ and substance P‐positive neurons. In conclusion, our findings identify Ikaros‐1 as a modulator of cell cycle exit of neural progenitors that gives rise to the neurogenesis of ENK‐positive striatal neurons. J. Comp. Neurol. 518:329–351, 2010. © 2009 Wiley‐Liss, Inc.
Distinct antennal lobe phenotypes in the leaf‐cutting ant (Atta vollenweideri)
Authors: Kuebler L.S. , Kelber C. , Kleineidam C.J. 
Published: September 2009

AbstractLeaf‐cutting ants (Atta vollenweideri) express a remarkable size polymorphism across the two sexual castes (queens and males) but in particular within the worker caste. Worker size is related to behavior (alloethism), separating workers into behavioral subcastes. The neuronal mechanisms underlying differences in behavior within the worker caste are still unknown. In this study, we first compared selected neuropils, in particular, the antennal lobes (AL) in males, queens, and workers. The males' ALs contain three extremely large, sex‐specific glomeruli (macroglomeruli; MGs) and in total comprise fewer glomeruli (242) than the ALs of queens (about 346 glomeruli). In contrast to males, the queen ALs contain only one large glomerulus at a lateral position. The largest number of glomeruli was found in workers (396–442). In a previous paper, we described an MG in the workers' AL, and, in the second part of this study, we show that within workers two distinct, size‐related AL phenotypes exist: the MG phenotype (containing a macroglomerulus) and the RG phenotype, with all glomeruli of regular size. This neuroanatomical polyphenism is established during pupal development and separates the worker caste into two neuroanatomical subcastes. Third, we investigate the functional significance of the MG in workers. By using calcium imaging to monitor activity of AL projection neurons, we show that the releaser component of the trail pheromone is represented in the same region as the MG. We propose that phenotypic trait variation in the organization of the ALs leads to differences in odor information processing that finally result in size‐related differences in trail‐following behavior. J. Comp. Neurol. 518:352–365, 2010. © 2009 Wiley‐Liss, Inc.
Distribution of leptin‐sensitive cells in the postnatal and adult mouse brain
Authors: Caron Emilie , Sachot Christelle , Prevot Vincent , Bouret Sebastien G. 
Published: September 2009

AbstractLeptin plays a pivotal role in the regulation of energy homeostasis and neuroendocrine functions, and increasing evidence indicates that leptin acts on the brain to mediate many of these effects. Recent data have also suggested that leptin influences brain development during early postnatal life. Here we examined the distribution of cells that express mRNA encoding the long form of the leptin receptor (LepRb) in postnatal and adult mouse brains by using in situ hybridization. In both adults and neonates, LepRb mRNA was largely restricted to regions known to control energy balance. Labeled cells were found in the arcuate, ventromedial, and dorsomedial nuclei of the hypothalamus as well as in the lateral hypothalamic area. Heavily labeled cells were also found in the median preoptic and ventral premammillary nuclei, two hypothalamic nuclei that are known to control reproduction. Moreover, during postnatal and adult life, clearly labeled cells were found in extrahypothalamic autonomic control sites such as the nucleus of the tractus solitarius. Importantly, this receptor can induce intracellular signaling because peripheral injection of leptin caused STAT3 phosphorylation in most sites in which LepRb mRNA was expressed. LepRb mRNA was also transiently elevated in certain regions of the postnatal mouse brain, such as the cortex, hippocampus, and laterodorsal nucleus of the thalamus. Taken together, these observations are consistent with the proposed roles of leptin in feeding and neuroendocrine regulation. They also identify regions where LepRb mRNA is expressed during early postnatal life and suggest new roles for leptin in the nervous system during development. J. Comp. Neurol. 518:459–476, 2010. © 2009 Wiley‐Liss, Inc.
Neurons associated with the flip‐flop activity in the lateral accessory lobe and ventral protocerebrum of the silkworm moth brain
Authors: Iwano Masaaki , Hill Evan S. , Mori Akio , Mishima Tatsuya , Mishima Tsuneko , Ito Kei , Kanzaki Ryohei 
Published: September 2009

AbstractThe lateral accessory lobe (LAL) and the ventral protocerebrum (VPC) are a pair of symmetrical neural structures in the insect brain. The LAL‐VPC is regarded as the major target of olfactory responding neurons as well as the control center for olfactory‐evoked sequential zigzag turns. Previous studies of the silkworm moth Bombyx mori showed that these turns are controlled by long‐lasting anti‐phasic activities of the flip‐flopping descending neurons with dendrites in the LAL‐VPC. To elucidate the neural mechanisms underlying the generation of this alternating activity between the LAL‐VPC units of both hemispheres, we first analyzed the detailed neural architecture of the LAL‐VPC and identified five subregions. We then investigated the morphology and physiological responses of the LAL‐VPC neurons by intracellular recording and staining and morphologically identified three types of bilateral neurons and three types of unilateral neurons. Bilateral neurons showed either brief or cyclic long‐lasting responses. At least some neurons of the latter type produced γ‐aminobutyric acid (GABA). Unilateral neurons linking the LAL and VPC, in contrast, showed long‐lasting or quick alternating activity. Timing analysis of the activity onset of each neural type suggests that quick reciprocal neural transmission between unilateral neurons would be responsible for the generation of long‐lasting activity in one LAL‐VPC unit, which lasts for up to a few seconds. Reciprocal inhibition and excitation by the bilateral neurons with long‐lasting activities would mediate the alternating long‐lasting activity between both LAL‐VPC units, which might last for up to 20 seconds. J. Comp. Neurol. 518:366–388, 2010. © 2009 Wiley‐Liss, Inc.
Microglial response to light‐induced photoreceptor degeneration in the mouse retina
Authors: Santos Ana M. , Martín‐Oliva David , Ferrer‐Martín Rosa M. , Tassi Mohamed , Calvente Ruth , Sierra Ana , Carrasco Maria‐Carmen , Marín‐Teva José L. , Navascués Julio , Cuadros Miguel A. 
Published: September 2009

AbstractThe microglial response elicited by degeneration of retinal photoreceptor cells was characterized in BALB/c mice exposed to bright light for 7 hours and then kept in complete darkness for survival times ranging from 0 hours to 10 days. Photodegeneration resulted in extensive cell death in the retina, mainly in the outer nuclear layer (ONL), where the photoreceptor nuclei are located. Specific immunolabeling of microglial cells with anti‐CD11b, anti‐CD45, anti‐F4/80, anti‐SRA, and anti‐CD68 antibodies revealed that microglial cells were activated in light‐exposed retinas. They migrated to the ONL, changed their morphology, becoming rounded cells with short and thick processes, and, finally, showed immunophenotypic changes. Specifically, retinal microglia began to strongly express antigens recognized by anti‐CD11b, anti‐CD45, and anti‐F4/80, coincident with cell degeneration. In contrast, upregulation of the antigen recognized by anti‐SRA was not detected by immunocytochemistry until 6 hours after light exposure. Differences were also observed at 10 days after light exposure: CD11b, CD45, and F4/80 continued to be strongly expressed in retinal microglia, whereas the expression of CD68 and SRA had decreased to near‐normal values. Therefore, microglia did not return to their original state after photodegeneration and continued to show a degree of activation. The accumulation of activated microglial cells in affected regions simultaneously with photoreceptor degeneration suggests that they play some role in photodegeneration. J. Comp. Neurol. 518:477–492, 2010. © 2009 Wiley‐Liss, Inc.
Finding order in chaos: a behavior model of the whole grid
Authors: Montes Jesús , Sánchez Alberto , Valdés Julio J. , Pérez María S. , Herrero Pilar 
Published: September 2009

AbstractOver the last decade, grid computing has paved the way for a new level of large‐scale‐distributed systems. However, this new step in distributed computing comes along with a completely new level of complexity. Grid management mechanisms play a key role, and a correct analysis and understanding of the grid behavior is needed. Traditional‐distributed computing management mechanisms analyze each resource separately and adjust specific parameters of each one of them. When trying to adapt the same procedures to grid computing, the vast complexity of the system can complicate this task. But grid complexity could only be a matter of perspective. It is possible to understand the grid behavior as a single system, instead of a set of resources. This abstraction could provide a deeper understanding of the system, describing large‐scale behavior and global events that probably would not be detected while analyzing each resource separately. In this paper a specific methodology is presented and described in order to create a global behavior model of the grid, analyzing it as a single entity. Both real and simulated case studies are also presented, in order to provide a proper validation and illustrate the benefits of this approach. Copyright © 2009 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Real‐Time Nanomicroscopy via Three‐Dimensional Single‐Particle Tracking
Authors: Katayama Yoshihiko , Burkacky Ondrej , Meyer Martin , Bräuchle Christoph , Gratton Enrico , Lamb Don C. 
Published: September 2009

AbstractWe developed a new method for real‐time, three‐dimensional tracking of fluorescent particles. The instrument is based on a laser‐scanning confocal microscope where the focus of the laser beam is scanned or orbited around the particle. Two confocal pinholes are used to simultaneously monitor regions immediately above and below the particle and a feedback loop is used to keep the orbit centered on the particle. For moderate count rates, this system can track particles with 15 nm spatial resolution in the lateral dimensions and 50 nm in the axial dimension at a temporal resolution of 32 ms. To investigate the interaction of the tracked particles with cellular components, we have combined our orbital tracking microscope with a dual‐color, wide‐field setup. Dual‐color fluorescence wide‐field images are recorded simultaneously in the same image plane as the particle being tracked. The functionality of the system was demonstrated by tracking fluorescent‐labeled artificial viruses in tubulin‐eGFP expressing HUH7 cells. The resulting trajectories can be used to investigate the microtubule network with super resolution.
Integration of electric drive vehicles in the Danish electricity network with high wind power penetration
Authors: C Divya K. , Østergaard Jacob , Larsen Esben , Kern Claus , Wittmann Tobias , Weinhold Michael 
Published: September 2009

AbstractThis paper presents the results of a study carried out to examine the feasibility of integrating electric drive vehicles (EDVs) in the Danish electricity network which is characterised by high wind power penetration. One of the main aims of this study was to examine the effect of EDVs on the Danish electricity network, wind power penetration and electricity market. In particular the study examined the effect of EDVs on the generation capacity constraints, load curve, cross border transmission capacity and the type of generating sources (renewable/conventional) which are likely to fuel these cars. The study was carried out considering the Danish electricity network state around 2025, when the EDV penetration levels would be significant enough to have an impact on the power system. Some of the interesting findings of this study are—EDVs have the potential to assist in integrating more wind power (by adding more market value to wind power and by improving over all power system reliability) and integration of EDV does not require major additional infrastructure (generation/transmission cross border capacities). Copyright © 2009 John Wiley & Sons, Ltd.