bluuebunny/crossref_metadata_2025_split huggingface dataset:
Motoneuron survival after chronic and sequential peripheral nerve injuries in the rat
Authors: Xu Qing-Gui , Forden Joanne , Walsh Sarah K. , Gordon Tessa , Midha Rajiv 
Published: September 2009

Object
Surgical repair of peripheral nerves following chronic nerve injury is associated with poor axonal regeneration and outcome. An underlying possibility is that chronic injuries may increase motoneuron cell death. The hypothesis that substantial motoneuron death follows chronic and sequential nerve injuries was tested in adult rats in this study.

Methods
Thirty adult male Lewis rats underwent bilateral multistage surgeries. At initial surgery, Fast Blue (FB) tracer was injected at a nerve-crush injury site in the right control femoral motor nerve. The left femoral motor nerve was transected at the same level and either capped to prevent regeneration (Group 1), or repaired to allow axonal regeneration and reinnervation of the target quadriceps muscle (Group 2) (15 rats in each group). After 8 weeks in 6 rats/group, the left femoral nerve was cut and exposed to FB just proximal to prior nerve capping or repair and the rats were evaluated for FB-labeled motoneuron counts bilaterally in the spinal cord (this was considered survival after initial injury). In the remaining 9 animals/group, the left nerve was recut (sequential injury), exposed to FB, and repaired to a fresh distal saphenous nerve stump to permit axonal regeneration. Following another 6 weeks, Fluoro-Gold, a second retrograde tracer, was applied to the cut distal saphenous nerve. This allowed us to evaluate the number of motoneurons that survived (maintained FB labeling) and the number of motoneurons that survived but that also regenerated axons (double labeled with FB and Fluoro-Gold).

Results
A mean number of 350 and 392 FB-labeled motoneurons were found after 8 weeks of nerve injury on the right and the left sides, respectively. This indicated no significant cell death due to initial nerve injury alone. A similar number (mean 390) of motoneurons were counted at final end point at 14 weeks, indicating no significant cell death after sequential and chronic nerve injury. However, only 50% (mean 180) of the surviving motoneurons were double labeled, indicating that only half of the population regenerated their axons.

Conclusions
The hypothesis that significant motoneuron cell death occurs after chronic and or sequential nerve injury was rejected. Despite cell survival, only 50% of motoneurons are capable of exhibiting a regenerative response, consistent with our previous findings of reduced regeneration after chronic axotomy.
Characterization of Aurintricarboxylic Acid as a Potent Hepatitis C Virus Replicase Inhibitor
Authors: Chen Ye , Bopda-Waffo Alain , Basu Amartya , Krishnan Ramalingam , Silberstein Erica , Taylor Deborah R , Talele Tanaji T , Arora Payal , Kaushik-Basu Neerja 
Published: September 2009

Background:Hepatitis C virus (HCV) NS5B is an essential component of the viral replication machinery and an important target for antiviral intervention. Aurintricarboxylic acid (ATA), a broad-spectrum antiviral agent, was evaluated and characterized for its anti-NS5B activity in vitro and in HCV replicon cells.Methods:Recombinant NS5B, HCV replicase and Huh-7 cells harbouring the subgenomic HCV replicon of genotype 1b were employed for biochemical and mechanistic investigations.Results:Analysis of ATA activity in vitro yielded equipotent inhibition of recombinant NS5B and HCV replicase in the submicromolar range (50% inhibition concentration [IC50] approximately 150 nM). Biochemical and mechanistic studies revealed a bimodal mechanism of ATA inhibition with characteristics of pyrophosphate mimics and non-nucleoside inhibitors. Molecular modelling and competition displacement studies were consistent with these parameters, suggesting that ATA might bind to the benzothiadiazine allosteric pocket 3 of NS5B or at its catalytic centre. Kinetic studies revealed a mixed mode of ATA inhibition with respect to both RNA and UTP substrates. Under single-cycle assay conditions, ATA inhibited HCV NS5B initiation and elongation from pre-bound RNA, but with ≥fivefold decreased potency compared with continuous polymerization conditions. The IC50value of ATA for the native replicase complex was 145 nM. In HCV replicon cells, ATA treatment ablated HCV RNA replication (50% effective concentration =75 nM) with concomitant decrease in NS5B expression and no apparent cytotoxic effects.Conclusions:This study identified ATA as a potent anti-NS5B inhibitor and suggests that its unique mode of action might be exploited for structural refinement and development of novel anti-NS5B agents.
Protumor vs Antitumor Functions of IL-17
Authors: Murugaiyan Gopal , Saha Bhaskar 
Published: September 2009

Abstract
Inflammation appears to be a necessity for both metastasis and elimination of tumor cells. IL-17, a proinflammatory cytokine produced by Th17 cells, contributes to both the processes by playing a dual role in the antitumor immunity. On one hand, IL-17 promotes an antitumor cytotoxic T cell response leading to tumor regression. On the other hand, by facilitating angiogenesis and egress of tumor cells from the primary focus, IL-17 promotes tumor growth. Thus, the therapeutic application that uses IL-17 needs to be refined by minimizing its protumor functions.
Cutting Edge: Contribution of Lung-Resident T Cell Proliferation to the Overall Magnitude of the Antigen-Specific CD8 T Cell Response in the Lungs following Murine Influenza Virus Infection
Authors: McGill Jodi , Legge Kevin L. 
Published: September 2009

Abstract
Following influenza virus infection, CD8 T cells encounter mature, Ag-bearing dendritic cells within the draining lymph nodes and undergo activation, programmed proliferation, and differentiation to effector cells before migrating to the lungs to mediate viral clearance. However, it remains unclear whether CD8 T cells continue their proliferation after arriving in the lungs. To address this question, we developed a novel, in vivo, dual-label system using intranasal CFSE and BrdU administration to identify virus-specific CD8 T cells that are actively undergoing cell division while in the lungs. With this technique we demonstrate that a high frequency of virus-specific CD8 T cells incorporate BrdU while in the lungs and that this lung-resident proliferation contributes significantly to the magnitude of the Ag-specific CD8 T cell response following influenza virus infection.
Cutting Edge: HLA-DM Functions through a Mechanism That Does Not Require Specific Conserved Hydrogen Bonds in Class II MHC-Peptide Complexes
Authors: Zhou Zemin , Callaway Kari A. , Weber Dominique A. , Jensen Peter E. 
Published: September 2009

Abstract
HLA-DM catalyzes peptide dissociation and exchange in class II MHC molecules through a mechanism that has been proposed to involve the disruption of specific components of the conserved hydrogen bond network in MHC-peptide complexes. HLA-DR1 molecules with alanine substitutions at each of the six conserved H- bonding positions were expressed in cells, and susceptibility to DM catalytic activity was evaluated by measuring the release of CLIP. The mutants αN62A, αN69A, αR76A, and βH81A DR1 were fully susceptible to DM-mediated CLIP release, and βN82A resulted in spontaneous release of CLIP. Using recombinant soluble DR1 molecules, the amino acid βN82 was observed to contribute disproportionately in stabilizing peptide complexes. Remarkably, the catalytic potency of DM with each β-chain mutant was equal to or greater than that observed with wild-type DR1. Our results support the conclusion that no individual component of the conserved hydrogen bond network plays an essential role in the DM catalytic mechanism.
Cutting Edge: CD4-Independent Development of Functional FoxP3+ Regulatory T Cells
Authors: Blache Céline , Adriouch Sahil , Calbo Sébastien , Drouot Laurent , Dulauroy Sophie , Arnoult Christophe , Le Corre Stéphanie , Six Adrien , Seman Michel , Boyer Olivier 
Published: September 2009

Abstract
The CD4 coreceptor is mandatory for the differentiation and function of conventional MHC class II-restricted T cells, but little is known about its contribution in regulatory T cells (Tregs). We thus investigated the Treg compartment in mice lacking CD4. CD3+CD8−FoxP3+ cells were readily detected in the periphery of CD4−/− mice, where their percentages were even increased as compared with wild-type animals. These cells had a classical CD25+CD152+GITR+ Treg phenotype, were enriched in memory-type Tregs, and displayed a diversified TCR repertoire. Functionally, CD4−/− Tregs were equally as suppressive as CD4+/+ Tregs in vitro as well as in vivo. Hence, the CD4 coreceptor is dispensable for the generation and function of FoxP3+ Tregs. Furthermore, CD3+CD8−FoxP3+ Tregs were also found to develop in the absence of both CD4 and MHC-II molecules, demonstrating that the generation of Tregs can occur independently of MHC-II recognition.
Perfluorinated Subphthalocyanine as a New Acceptor Material in a Small‐Molecule Bilayer Organic Solar Cell
Authors: Gommans Hans , Aernouts Tom , Verreet Bregt , Heremans Paul , Medina Anaïs , Claessens Christian G. , Torres Tomas 
Published: September 2009

AbstractThe complex refractive index of fluorinated subphthalocyanines (SubPcs) deposited by vacuum sublimation is determined by spectral ellipsometry. Their performance as acceptor material is characterized in a range of donor/acceptor heterojunctions in organic photovoltaic cells (OPVCs) by current–voltage measurements under 1 sun AM 1.5D simulated solar illumination and spectral response. Both electron and hole transfer between donor and acceptor materials is demonstrated. Power conversion efficiencies of 0.96% are found with an open‐circuit bias of 940 mV. Hence, it is shown that fluorinated SubPcs can be considered as an acceptor material in OPVCs with an absorption in the visible comparable to that of well‐known metallophthalocyanines.
Charge storage performance of polyetherimide Ultem®1000—Influence of secondary antioxidants and purification
Authors: Erhard Dominik P. , Giesa Reiner , Altstädt Volker , Schmidt Hans‐Werner 
Published: September 2009

AbstractThe performance of a polymeric electret material depends on many parameters, and besides chemical structure, charging conditions, and application temperature, other factors, such as grade, manufacturer, processing history, and additive package, are critical. Commercial polyetherimide (PEI) Ultem®1000 films exhibited satisfying electret properties as revealed by an isothermal potential decay (ITPD) to 75% of the initial surface charge after 24 h at 90°C. It was found that after purification by reprecipitation this value drops to 34% and that the same PEI synthesized by two different methods revealed to be a very poor electret with charge retention of almost zero. Assuming that an additive in the commercial material might be responsible for this behavior, we identified an organophosphonite which is commonly used as antioxidant in high‐temperature polymers. We incorporated this additive by melt compounding into purified PEI and found a dramatic increase in charge retention to 79% of the initial charge at an additive load level of 0.5 wt %. By immersing Ultem®1000 films in water, the electret behavior was further improved and almost 100% charge retention was achieved. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Three‐Dimensional Serial Section Computer Reconstruction of the Arrangement of the Structural Components of the Parabronchus of the Ostrich, Struthio Camelus Lung
Authors: Maina John N. , Woodward Jeremy D. 
Published: September 2009

AbstractThe Ostrich, Struthio camelus is the largest extant bird. The arrangement of the airway and the vascular components of the parabronchus of its lung were investigated by 3D serial section reconstruction. Modestly developed atrial muscles, shallow atria, paucity of infundibulae with preponderant origination of the air capillaries (ACs) from the atria and lack of interparabronchial septa, structural features that epitomize lungs of most highly derived metabolically active volant birds were observed. Intertwined very closely, the ACs and the blood capillaries (BCs) are not straight, blind‐ended tubules that run in contact, counter and parallel to each other as has been claimed and/or modeled. Crosscurrent (perpendicular = orthogonal) orientation between the centripetal (inward) flow of the venous blood (VB) from the periphery of the parabronchus and the flow of air in the parabronchial lumen occur. Also, a countercurrent‐like arrangement between the ACs which convey air centrifugally (outwards = radially) and the BCs that transport venous blood centripetally (inwards) was identified. The VB is conveyed to the parabronchus by the interparabronchial arteries and delivered to the exchange tissue by the intraparabronchial arterioles: it is then arterialized at the infinitely many points where the ACs and the BCs contact. Functionally, the crosscurrent arrangement grants a multicapillary serial arterialization arrangement which extends the time that the respiratory media, air and blood, are exposed to each other. The contribution that the countercurrent‐like arrangement makes to the gas exchange process remains obscure. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.
Immunolocalization of G‐Protein Alpha Subunits in the Olfactory System of the Cartilaginous Fish Scyliorhinus Canicula
Authors: Ferrando Sara , Gambardella Chiara , Ravera Silvia , Bottero Sergio , Ferrando Tiziana , Gallus Lorenzo , Manno Valentina , Salati Amir P. , Ramoino Paola , Tagliafierro Grazia 
Published: September 2009

AbstractIn the olfactory and vomeronasal systems of vertebrates, the morphology of the receptor neurons, the receptor gene family they express, the G‐protein coupled with the receptor (in particular the G‐protein alpha subunit), and their projection to the olfactory bulb are correlated. Much information about this complicated system have been collected in different groups, but nothing is known about Chondrichthyes. In this work, the presence and distribution of immunoreactivity for different types of G‐protein alpha subunit (Gαo, Gαq and Gαs/olf) were investigated in the olfactory mucosa and olfactory bulb of the shark Scyliorhinus canicula. Only Gαo‐like immunoreactivity was detected in the olfactory mucosa and bulb, both in tissues and homogenates. Its distribution was partially similar to that found in other vertebrates: it was localized in the microvillous receptor neurons, in numerous axon bundles of the fila olfactoria, in the stratum nervosum and in the most of glomeruli in the stratum glomerulosum. No immunoreactivity was instead observed in the crypt neurons, the second type of olfactory neurons present in cartilaginous fish. The projections of crypt neurons to olfactory bulb probably correspond to the few ventrally‐located glomeruli which were negative to the antiserum against Gαo. These data suggest, in S. canicula, different olfactory neuron types send projections to the olfactory bulb with a segregated distribution, as observed in other vertebrates. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.
Normal Morphology and Hormone Receptor Expression in the Male California Sea Lion (Zalophus californianus) Genital Tract
Authors: Colegrove Kathleen M. , Gulland Frances M.D. , Naydan Diane K. , Lowenstine Linda J. 
Published: September 2009

AbstractHistomorphology and estrogen α (ER α), and progesterone receptor (PR) expression were evaluated in free‐ranging stranded male California sea lions (Zalophus californianus). Hormone receptor expression was evaluated using an immunohistochemical technique with monoclonal antibodies. Estrogen and PRs were identified in the efferent ductules, prostate gland, corpus cavernosa, corpus spongiosium, penile urethra, and in the epithelium and stroma of both the penis and prepuce. In some tissues, ER α expression was more intense in the stroma, emphasizing the importance of the stroma in hormone‐mediated growth and differentiation of reproductive organs. To our knowledge, this is the first study to localize ER α and PR to the epithelium of the glans penis. The results of this investigation add to the general knowledge of male California sea lion reproduction and suggest that estrogens could have a role in the function of the male reproductive tract. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.
Silica‐Coated Metal Nanoparticles
Authors: Liu Shuhua , Han Ming‐Yong 
Published: September 2009

AbstractThe advanced high‐quality synthesis of dense and porous silica‐coated nanostructures is enjoying ever‐increasing research interests for their important properties and diverse applications, especially for catalytic, controlled release, colorimetric diagnostics, photothermal therapy, surface enhanced Raman scattering (SERS) detection, and so forth. In this timely Focus Review, we summarize the up‐to‐date synthesis strategies, improved properties, and emerging applications of silica‐coated metal nanoparticles. In particular, the large scale synthesis of silica‐coated metal nanoparticles and the recent development of hollowed‐out silica‐coated metal nanoparticles by silica dissolution are emphasized for new and practical applications.
A comparison of uptake of metformin and phenformin mediated by hOCT1 in human hepatocytes
Authors: Sogame Yoshihisa , Kitamura Atsushi , Yabuki Masashi , Komuro Setsuko 
Published: September 2009

AbstractMetformin, a biguanide that has been used to treat type 2 diabetes mellitus, is reportedly transported into human hepatocytes by human organic cation transporter 1 (hOCT1). The objective of this study was to investigate differences in the hepatic uptake of metformin and phenformin, a biguanide derivative similar to metformin. Special focus was on the role of active transport into cells. Experiments were therefore performed using human cryopreserved hepatocytes and hOCT1 expressing oocytes. Both biguanides proved to be good substrates for hOCT1. However, phenformin exhibited a much higher affinity and transport activity, with a marked difference in uptake kinetics compared with metformin. Both biguanides were transported actively by hOCT1, with the active transport components much greater than passive transport components in both cases, suggesting that functional changes in hOCT1 might affect the transport of both compounds to the same degree. This study for the first time produced detailed comparative findings for uptake profiles of metformin and phenformin in human hepatocytes and hOCT1 expressing oocytes. It is considered that hOCT1 may not be the only key factor that determines the frequency of metformin and phenformin toxicity, considering the major contribution of this transporter to the total hepatic uptake and comparable width of their therapeutic concentrations. Copyright © 2009 John Wiley & Sons, Ltd.
Heating‐induced conformational change of a novel β‐(1→3)‐D‐glucan from Pleurotus geestanus
Authors: Zhang Mei 
Published: September 2009

AbstractRecently, we isolated and purified a neutral polysaccharide (PGN) from edible fungus Pleurotus geestanus. Its structure was characterized by a range of physical–chemical methods, including high performance anion exchange chromatography, uronic acid, and protein analyses, size exclusion chromatography with ultraviolet, refractive index and light scattering detectors, and nuclear magnetic resonance. Our results revealed that PGN is a novel β‐(1→3)‐D‐glucan with glucose attached to every other sugar residues at Position 6 in the backbone. It has a degree of branching of 1/2. Such structure is different from typical β‐(1→3)‐D‐glucans schizophyllan and lentinan in which DB is 1/3 and 2/5, respectively. Rheological study showed a very interesting melting behavior of PGN in water solution: heating PGN in water leads to two transitions, in the range of 8–12.5°C and 25–60°C, respectively. The melting behavior and conformational changes were characterized by rheometry, micro‐differential scan calorimetry, atomic force microscopy, static and dynamic light scattering at different temperatures. The first heating‐induced transition corresponds to the disintegration of polymer bundles into small helical clusters, resembling the heating‐induced dissociation of SPG in water at 7°C; the second one might correspond to the dissociation of helical strands to individual chains. The ability of PGN to undergo a conformation/viscosity transition in water upon heating is very valuable to immobilize cells or enzymes or therapeutic DNA/RNA, which makes PGN a potentially useful biomaterial. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 121–131, 2010.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Interplay between protein homeostasis networks in protein aggregation and proteotoxicity
Authors: Douglas Peter M. , Cyr Douglas M. 
Published: September 2009

AbstractThe misfolding and aggregation of disease proteins is characteristic of numerous neurodegenerative diseases. Particular neuronal populations are more vulnerable to proteotoxicity while others are more apt to tolerate the misfolding and aggregation of disease proteins. Thus, the cellular environment must play a significant role in determining whether disease proteins are converted into toxic or benign forms. The endomembrane network of eukaryotes divides the cell into different subcellular compartments that possess distinct sets of molecular chaperones and protein interaction networks. Chaperones act as agonists and antagonists of disease protein aggregation to prevent the accumulation of toxic intermediates in the aggregation pathway. Interacting partners can also modulate the conformation and localization of disease proteins and thereby influence proteotoxicity. Thus, interplay between these protein homeostasis network components can modulate the self‐association of disease proteins and determine whether they elicit a toxic or benign outcome. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 229–236, 2010.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
The effect of deuterium oxide on the stability of the collagen model peptides H‐(Pro‐Pro‐Gly)10‐OH, H‐(Gly‐Pro‐4(R)Hyp)9‐OH, and Type I collagen
Authors: Mizuno Kazunori , Bächinger Hans Peter 
Published: September 2009

AbstractThe collagen triple helix has a larger accessible surface area per molecular mass than globular proteins, and therefore potentially more water interaction sites. The effect of deuterium oxide on the stability of collagen model peptides and Type I collagen molecules was analyzed by circular dichroism and differential scanning calorimetry. The transition temperatures (Tm) of the protonated peptide (Pro‐Pro‐Gly)10 were 25.4 and 28.7°C in H2O and D2O, respectively. The increase of the Tm of (Pro‐Pro‐Gly)10 measured calorimetrically at 1.0°C min−1 in a low pH solution from the protonated to the deuterated solvent was 5.1°C. The increases of the Tm for (Gly‐Pro‐4(R)Hyp)9 and pepsin‐extracted Type I collagen were measured as 4.2 and 2.2°C, respectively. These results indicated that the increase in the Tm in the presence of D2O is comparable to that of globular proteins, and much less than reported previously for collagen model peptides [Gough and Bhatnagar, J Biomol Struct Dyn 1999, 17, 481–491]. These experimental results suggest that the interaction of water molecules with collagen is similar to the interaction of water with globular proteins, when the ratio of collagen to water is very small and collagen is monomerically dispersed in the solvent. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 93–101, 2010.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com