bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of transient receptor potential ankyrin 1 (TRPA1) in the rat trigeminal sensory afferents and spinal dorsal horn
Authors: Kim Yun Sook , Son Jae Youn , Kim Tae Heon , Paik Sang Kyoo , Dai Yi , Noguchi Koichi , Ahn Dong Kuk , Bae Yong Chul 
Published: October 2009

AbstractTransient receptor potential ankyrin 1 (TRPA1), responding to noxious cold and pungent compounds, is implicated in the mediation of nociception, but little is known about the processing of the TRPA1‐mediated nociceptive information within the trigeminal sensory nuclei (TSN) and the spinal dorsal horn (DH). To address this issue, we characterized the TRPA1‐positive (+) neurons in the trigeminal ganglion (TG) and investigated the distribution of TRPA1+ afferent fibers and their synaptic connectivity within the rat TSN and DH by using light and electron microscopic immunohistochemistry. In the TG, TRPA1 was expressed in unmyelinated and small myelinated axons and also occasionally in large myelinated axons. Many TRPA1+ neurons costained for the marker for peptidergic neurons substance P (26.8%) or the marker for nonpeptidergic neurons IB4 (44.5%). In the CNS, small numbers of axons and terminals were immunopositive for TRPA1 throughout the rostral TSN, in contrast to the dense network of positive fibers and terminals in the superficial laminae of the trigeminal caudal nucleus (Vc) and DH. The TRPA1+ terminals contained clear round vesicles, were presynaptic to one or two dendrites, and rarely participated in axoaxonic contacts, suggesting involvement in relatively simple synaptic circuitry with a small degree of synaptic divergence and little presynaptic modulation. Immunoreactivity for TRPA1 was also occasionally observed in postsynaptic dendrites. These results suggest that TRPA1‐dependent orofacial and spinal nociceptive input is processed mainly in the superficial laminae of the Vc and DH in a specific manner and may be processed differently between the rostral TSN and Vc. J. Comp. Neurol. 518:687–698, 2010. © 2009 Wiley‐Liss, Inc.
Regional and subcellular distribution of HDAC4 in mouse brain
Authors: Darcy Michael J. , Calvin Kate , Cavnar Katie , Ouimet Charles C. 
Published: October 2009

AbstractHistone deacetylases (HDACs) are part of a system that links epigenetic control of gene expression to a variety of environmental stimuli. Some HDACs, including HDAC4, shuttle between the cytoplasm and nucleus in response to physiological cues such as calcium signaling. HDAC4 mRNA is enriched in the brain, but the regional and subcellular protein expression pattern of HDAC4 is not known. Here we show that HDAC4 is more highly expressed in some brain regions than in others. HDAC4 is present in the perikaryial cytoplasm of most neurons but its nuclear localization is variable. In some areas, such as the dentate gyrus, nuclear expression is not detectable, whereas in other areas some neuronal nuclei contain HDAC4 immunoreactivity whereas others do not. In the cytoplasm, HDAC4 immunoreactivity is punctate. Some of these puncta are present in dendritic spines where the strongest immunoreactivity is associated with the postsynaptic density. These data demonstrate that the regional and subcellular distribution of HDAC4 is heterogeneous and raise the possibilities that HDAC4 acts on nonhistone substrates in dendritic spines or that it shuttles between spine and nucleus to coordinate synaptic activity with gene expression. J. Comp. Neurol. 518:722–740, 2010. © 2009 Wiley‐Liss, Inc.
Ultrafast Relaxation Dynamics of the Excited States of 1‐Amino‐ and 1‐(N,N‐Dimethylamino)‐fluoren‐9‐ones
Authors: Varne Mahendra , Samant Vaishali , Mondal Jahur A. , Nayak Sandip K. , Ghosh Hirendra N. , Palit Dipak K. 
Published: October 2009

AbstractThe dynamics of the excited states of 1‐aminofluoren‐9‐one (1AF) and 1‐(N,N‐dimethylamino)‐fluoren‐9‐one (1DMAF) are investigated by using steady‐state absorption and fluorescence as well as subpicosecond time‐resolved absorption spectroscopic techniques. Following photoexcitation of 1AF, which exists in the intramolecular hydrogen‐bonded form in aprotic solvents, the excited‐state intramolecular proton‐transfer reaction is the only relaxation process observed in the excited singlet (S1) state. However, in protic solvents, the intramolecular hydrogen bond is disrupted in the excited state and an intermolecular hydrogen bond is formed with the solvent leading to reorganization of the hydrogen‐bond network structure of the solvent. The latter takes place in the timescale of the process of solvation dynamics. In the case of 1DMAF, the main relaxation pathway for the locally excited singlet, S1(LE), or S1(ICT) state is the configurational relaxation, via nearly barrierless twisting of the dimethylamino group to form the twisted intramolecular charge‐transfer, S1(TICT), state. A crossing between the excited‐state and ground‐state potential energy curves is responsible for the fast, radiationless deactivation and nonemissive character of the S1(TICT) state in polar solvents, both aprotic and protic. However, in viscous but strong hydrogen‐bond‐donating solvents, such as ethylene glycol and glycerol, crossing between the potential energy surfaces for the ground electronic state and the hydrogen‐bonded complex formed between the S1(TICT) state and the solvent is possibly avoided and the hydrogen‐bonded complex is weakly emissive.
Biomimetic F‐Actin Cortex Models
Authors: Haraszti Tamás , Clemen Anabel E.‐M. , Spatz Joachim P. 
Published: October 2009

AbstractSince its first production from muscle tissue more than 65 years ago, our knowledge about actin has come a long way. While at the beginning it was identified as a muscle protein, nowadays actin is considered as one of the most important components of the cytoskeleton, playing a crucial role in cell motility, adhesion, morphology and intracellular transport processes. In vitro models have been constructed for about 20 years to gain better insight into the chemophysical and biomechanical properties of actin networks by being able to reduce and tune its complexity. The complexity of these models ranges from single actin filaments (F‐actin) in interaction with actin‐associated molecules and proteins, F‐actin network gels to F‐actin loaded vesicles to freely suspended F‐actin networks in microfluidic environments. This review summarizes the development of F‐actin network models and highlights their applicability towards step‐by‐step construction of complex cortex mimicking systems.
Rapid Prediction of the Hydrogen Bond Cooperativity inN‐methylacetamide Chains
Authors: Jiang Xiao‐Nan , Wang Chang‐Sheng 
Published: October 2009

AbstractA method is proposed to rapidly predict the hydrogen bond cooperativity inN‐methylacetamide chains. The parameters needed are obtained from the fittings to the hydrogen bonding energies in the formamide chains containing 2 to 8 monomeric units. The scheme is then used to calculate the individual hydrogen bonding energies inN‐methylacetamide chains containing 2 to 7 monomeric units. The cooperativity predicted is in good agreement with those obtained from MP2/6‐31+G** calculations by including the BSSE correction. Our scheme is further employed to predict the individual hydrogen bonding energies in largerN‐methylacetamide chains containing up to 200 monomericN‐methylacetamide units, to which the MP2 method cannot be applied. Based on our scheme, a cooperative effect of over 170 % of the dimer hydrogen bonding energy in longN‐methylacetamide chains is predicted. The method is also applied to heterogeneous chains containing formamide, acetamide,N‐methylformamide, andN‐methylacetamide. The individual hydrogen bonding energies in these heterogeneous chains are also in good agreement with those obtained from MP2 calculations with the BSSE correction, further demonstrating that our method is reasonable.
Probing Biomembrane Dynamics by Dual‐Wavelength Reflection Interference Contrast Microscopy
Authors: Monzel Cornelia , Fenz Susanne F. , Merkel Rudolf , Sengupta Kheya 
Published: October 2009

AbstractWe present an improved analysis of reflection interference contrast microscopy (RICM) images, recorded to investigate model membrane systems that mimic cell adhesion. The model systems were giant unilamellar vesicles (GUV) adhering via specific ligand–receptor interactions to supported lipid bilayers (SLB) or to patterns of receptors. Conventional RICM and dual‐wavelength RICM (DW–RICM) were applied to measure absolute optical distances between the biomembranes and planar substrates. We developed algorithms for a straightforward implementation of an automated, time‐resolved reconstruction of the membrane conformations from RICM/DW–RICM images, taking into account all the interfaces in the system and blurring of the data due to camera noise. Finally, we demonstrate the validity and usefulness of this new approach by analyzing the topography and fluctuations of a bound membrane in the steady state and its dynamic adaptation to osmotic pressure changes. These measurements clearly show that macroscopic membrane flow through tightly adhered area is possible in our system.
NBDT (3‐(N‐(7‐nitrobenz‐2‐oxa‐1,3‐diazol‐4‐yl)amino)‐3‐toluene)—A novel fluorescent dye for studying mechanisms of toluene uptake into vital bacteria
Authors: Sträuber H. , Hübschmann T. , Jehmlich N. , Schmidt F. , von Bergen M. , Harms H. , Müller S. 
Published: October 2009

AbstractUptake of small hydrophobic substances such as toluene into bacteria is widely assumed to occur by passive diffusion. Some toluene degrading bacteria, however, are described to contain uptake systems which may be involved in the transport of this compound. In this study, a fluorescently labeled toluene analogue dye (3‐(N‐(7‐nitrobenz‐2‐oxa‐1,3‐diazol‐4‐yl)amino)‐3‐toluene; NBDT), flow cytometry, and shot gun proteome analysis were used to follow toluene uptake into bacteria in more detail. The new dye has excitation peaks at 444 and 475 nm and an emission peak at 537 nm. The toluene‐degraders P. putida mt‐2 and P. putida F1 as well as P. putida KT2440 and E. coli K12 as negative controls were included. To enable quantification of NBDT uptake, carbonyl cyanide 3‐chlorophenylhydrazone (CCCP) was added to inactivate NBDT efflux pumps. The porin inhibitor cadaverine was added to study the porin‐mediated influx of toluene. Cadaverine reduced NBDT uptake by toluene‐grown P. putida mt‐2 and F1 by 25% and 42%, respectively, thus revealing an involvement and possibly a regulatory function of porins in the uptake of the toxic substrate toluene. Shot gun proteome measurements gave evidence for the presence of toluene transporting porins in P. putida mt‐2 grown on toluene but not when grown on glucose. © 2009 International Society for Advancement of Cytometry
Adaptive smooth multicast protocol for multimedia transmission: Implementation details and performance evaluation
Authors: Bouras Christos , Gkamas Apostolos , Kioumourtzis Georgios 
Published: October 2009

AbstractIn this paper we propose a new single‐rate multicast congestion control scheme named Adaptive Smooth Multicast Protocol (ASMP), for multimedia transmission over best‐effort networks. The smoothness lays in the calculation and adaptation of the transmission rate, which is based on dynamic estimations of protocols' parameters and dynamic adjustment of the ‘smoothness factor’, as well. ASMP key attributes are: (a) TCP‐friendly behavior, (b) adaptive scalability to large sets of receivers, (c) high bandwidth utilization, and finally (d) smooth transmission rates, which are suitable for multimedia applications. We evaluate the performance of ASMP and investigate its behavior under various network conditions through extensive simulations conducted with the network simulator software (ns2). Simulation results show that ASMP can be regarded as a serious competitor of TFMCC and PGMCC. In many cases, ASMP outperforms TFMCC in terms of TCP‐friendliness and smooth transmission rates, while PGMCC presents lower scalability than ASMP. We have implemented ASMP on top of RTP/RTCP protocols in ns2 by adding all the RTP/RTCP protocol's attributes that are defined in RFC 3550 and related to quality of service metrics. Copyright © 2009 John Wiley & Sons, Ltd.
New hemocyte‐specific enhancer‐reporter transgenes for the analysis of hematopoiesis in Drosophila
Authors: Tokusumi Tsuyoshi , Shoue Douglas A. , Tokusumi Yumiko , Stoller Jessica R. , Schulz Robert A. 
Published: October 2009

AbstractBased on environmental challenges or altered genetic composition, Drosophila larvae can produce up to three types of blood cells that express genetic programs essential for their distinct functions. Using transcriptional enhancers for genes expressed exclusively in plasmatocytes, crystal cells, or lamellocytes, several new hemocyte‐specific enhancer‐reporter transgenes were generated to facilitate the analysis of Drosophila hematopoiesis. This approach took advantage of fluorescent variants of insulated P‐element reporter vectors for multilabeling cell analyses; two additional color variants were generated in these studies. These vectors were successfully used to produce transgenic fly lines that label specific hemocyte lineages with separate colors. Combining three transgene reporters allowed for the unambiguous identification of plasmatocytes, crystal cells, and lamellocytes within a complex hemocyte population. While this work focused on the hematopoietic process, these new vectors can be used to mark multiple cell types or trace complex cell lineages during any chosen aspect of Drosophila development. genesis 47:771–774, 2009. © 2009 Wiley‐Liss, Inc.
Dual fluorescent protein reporters for studying cell behaviors in vivo
Authors: Stewart M. David , Jang Chuan‐Wei , Hong Nicholas W. , Austin Anthony P. , Behringer Richard R. 
Published: October 2009

AbstractHeLa cells transfected with plasmids expressing dual fluorescent protein reporters with cherry, green, and cyan fluorscent proteins. Histone 2B fusions localize fluorescent proteins to the nucleus, while fluorescent proteins fused to glycosylphosphatidylinositol anchor signal sequence localizes to plasma membranes. These dual fluorescent reporters label nuclear and plasma membranes of live cells to follow their behaviors in developing embryos. See the paper by Stewart et al. in this issue.
Critical role for the immunoproteasome subunit LMP7 in the resistance of mice to Toxoplasma gondii infection
Authors: Tu Liping , Moriya Chikako , Imai Takashi , Ishida Hidekazu , Tetsutani Kohhei , Duan Xuefeng , Murata Shigeo , Tanaka Keiji , Shimokawa Chikako , Hisaeda Hajime , Himeno Kunisuke 
Published: October 2009

AbstractProteasome‐mediated proteolysis is responsible for the generation of immunogenic epitopes presented by MHC class I molecules, which activate antigen‐specific CD8+ T cells. Immunoproteasomes, defined by the presence of the three catalytic subunits LMP2, MECL‐1, and LMP7, have been hypothesized to optimize MHC class I antigen processing. In this study, we demonstrate that the infection of mice with a protozoan parasite, Toxoplasma gondii, induced the expression of LMP7 mRNA in APC and increased the capacity of APC to induce the production of IFN‐γ by antigen‐specific CD8+ T cells. In vitro infection of a DC cell line with T. gondii also induced the expression of LMP7 and resulted in enhanced proteasome proteolytic activity. Finally, mice lacking LMP7 were highly susceptible to infection with T. gondii and showed a reduced number of functional CD8+ T cells. These results demonstrate that proteasomes containing LMP7 play an indispensable role in the survival of mice infected with T. gondii, presumably due to the efficient generation of CTL epitopes required for the functional development of CD8+ T cells.
Reassessing the role of HLA‐DRB3 T‐cell responses: Evidence for significant expression and complementary antigen presentation
Authors: Faner Rosa , James Eddie , Huston Laurie , Pujol‐Borrel Ricardo , Kwok William W. , Juan Manel 
Published: October 2009

AbstractIn humans, several HLA‐DRB loci (DRB1/3/4/5) encode diverse β‐chains that pair with α‐chains to form DR molecules on the surface of APC. While DRB1 and DRB5 have been extensively studied, the role of DRB3/4 products of DR52/DR53 haplotypes has been largely neglected. To clarify the relative expression of DRB3, we quantified DRB3 mRNA levels in comparison with DRB1 mRNA from the same haplotype in both B cells and monocytes, observing quantitatively significant DRB3 synthesis. In CD19+ cells, DRB1*03/11/13 was 3.5‐fold more abundant than DRB3, but in CD14+ this difference was only two‐fold. Monocytes also had lower overall levels of DR mRNA compared with B cells, which was confirmed by cell surface staining of DRB1 and DRB3. To evaluate the functional role of DRB3, tetramer‐guided epitope mapping was used to detect T cells against tetanus toxin and several influenza antigens presented by DRB3*0101/0202 or DRB1*03/11/13. None of the epitopes discovered were shared among any of the DR molecules. Quantitative assessment of DRB3‐tetanus toxin specific T cells revealed that they are present at similar frequencies as those observed for DRB1. These results suggest that DRB3 plays a significant role in antigen presentation with different epitopic preferences to DRB1. Therefore, DRB3, like DRB5, serves to extend and complement the peptide repertoire of DRB1 in antigen presentation.
Butyrate mediates nucleotide‐binding and oligomerisation domain (NOD) 2‐dependent mucosal immune responses against peptidoglycan
Authors: Leung Chung‐Hang , Lam Wing , Ma Dik‐Lung , Gullen Elizabeth A. , Cheng Yung‐Chi 
Published: October 2009

AbstractThe interaction between digestive tract microbiological flora and food has an important influence on human health. Butyrate is produced during the fermentation of dietary fibres by intestinal bacteria and plays an important role in the regulation of mucosal immunity. In this report, we studied the impact of butyrate on the defence mechanism against the bacterial membrane component peptidoglycan (PGN). Butyrate was found to enhance PGN‐mediated IL‐8 and GRO‐α production. The expression of these chemokines required the activation of NF‐κB and was dependent on the concentrations of butyrate and PGN. Butyrate was found to up‐regulate nucleotide‐binding and oligomerisation domain (NOD) 2, but not NOD1 or TLR2. NOD2 up‐regulation was mediated by an increase in histone acetylation in the Nod2 promoter region, leading to enhanced PGN‐induced IL‐8 and GRO‐α secretion. Knockdown of NOD2 and TLR2 by siRNA significantly reduced PGN‐mediated chemokine production, suggesting that both NOD2 and TLR2 are required for maximal response. Our findings provide a better understanding of the mechanism by which butyrate regulates mucosal immunity for normal intestinal function. Based on the results of this study, we infer that dietary fibres can impact inflammatory bowel diseases.
Chemokine receptor Ccr5 deficiency induces alternative macrophage activation and improves long‐term renal allograft outcome
Authors: Dehmel Stefan , Wang Shijun , Schmidt Claudia , Kiss Eva , Loewe Robert P. , Chilla Silvia , Schlöndorff Detlef , Gröne Hermann‐Josef , Luckow Bruno 
Published: October 2009

AbstractThe chemokine (C‐C motif) receptor 5 (CCR5) has been implicated in experimental and clinical allograft rejection. To dissect the function of CCR5 in acute and chronic renal allograft rejection, bilaterally nephrectomized WT and Ccr5−/− C57BL/6 mice were used as recipients of WT BALB/c renal allografts and analyzed 7 and 42 days after transplantation. Lesion scores (glomerular damage, vascular rejection, tubulointerstitial inflammation) and numbers of CD4+, CD8+, CD11c+ and alpha smooth muscle actin (αSMA)+ cells were reduced in allografts from Ccr5−/− recipients during the chronic phase. Increasing creatinine levels indicated deterioration of allograft function over time. While mRNA expression of Th1‐associated markers decreased between 7 and 42 days, Th2‐associated markers increased. Markers for alternatively activated macrophages (arginase 1, chitinase 3‐like 3, resistin‐like α, mannose receptor, C type 1), were strongly upregulated (mRNA and/or protein level) only in allografts from Ccr5−/− recipients at 42 days. Ccr5 deficiency shifted intragraft immune responses during the chronic phase towards the Th2 type and led to accumulation of alternatively activated macrophages. Additionally, splenocytes from unchallenged Ccr5−/− mice showed significantly increased arginase 1 and mannose receptor 1 mRNA levels, suggesting constitutive alternative activation of splenic macrophages. We conclude that Ccr5 deficiency favors alternative macrophage activation. This finding may be relevant for other inflammatory diseases that involve macrophage activation and may also influence future therapeutic strategies targeting CCR5.
HIV gag protein is efficiently cross‐presented when targeted with an antibody towards the DEC‐205 receptor in Flt3 ligand‐mobilized murine DC
Authors: Bozzacco Leonia , Trumpfheller Christine , Huang Yaoxing , Longhi Maria Paula , Shimeliovich Irina , Schauer Joseph D. , Park Chae Gyu , Steinman Ralph M. 
Published: October 2009

AbstractDC present exogenous proteins to MHC class I‐restricted CD8+ T cells. This function does not require endogenous antigen synthesis within DC, providing the potential to elicit CD8+ T‐cell responses to immune complexes, inactivated microbes, dying cells, and proteins such as OVA. In mice, the CD8+ or DEC‐205+ DC are specialized for cross‐presentation, and this subset can be increased 10‐fold in numbers following Fms‐like tyrosine kinase 3 ligand (Flt3L) treatment in vivo. Therefore, we studied cross‐presentation by abundant Flt3L DC using HIV gag protein. When enriched by positive selection with anti‐CD11c beads, cells from Flt3L mice are not only more abundant but are also more highly enriched in CD11chigh DC, particularly the DEC‐205+ subset. DC cross‐present HIV gag to primed CD8+ T cells, but when the antigen is delivered within an antibody to DEC‐205 receptor, cross‐presentation becomes 100‐fold more efficient than non‐targeted antigen. This finding requires gag to be engineered into anti‐DEC antibody, not just mixed with antibody. Flt3L DC are a valuable tool to study cross‐presentation, since their use overcomes the obstacle posed by the low number of cross‐presenting DC in the steady state. These findings support future experiments to use Flt3L to enhance presentation of DC‐targeted vaccines.
The antimicrobial activity of CCL28 is dependent on C‐terminal positively‐charged amino acids
Authors: Liu Bin , Wilson Eric 
Published: October 2009

AbstractSeveral chemokines have been shown to act as antimicrobial proteins, suggesting a direct contribution to innate immune protection. Based on the study of defensins and other antimicrobial peptides, it has been proposed that cationic amino acids in these proteins play a key role in their antimicrobial activity. The primary structure requirements necessary for the antimicrobial activity of chemokines, however, have not yet been elucidated. Using mouse CCL28, we have identified a C‐terminal region of highly‐charged amino acids (RKDRK) that is essential to the antimicrobial activity of the murine chemokine. Additionally, other positively‐charged amino acids in the C‐terminus of the protein contribute to the observed antimicrobial effect. Charge reversal and deletion mutations support our hypothesis that C‐terminal positively‐charged amino acids are essential for the antimicrobial activity of CCL28. Results also demonstrate that although the C‐terminal region of the chemokine is essential, it is not sufficient for full antimicrobial activity of CCL28.