bluuebunny/crossref_metadata_2025 huggingface dataset:
The fusing ability of sperm is bestowed by CD9-containing vesicles released from eggs in mice
Authors: Miyado Kenji , Yoshida Keiichi , Yamagata Kazuo , Sakakibara Keiichi , Okabe Masaru , Wang Xiaobiao , Miyamoto Kiyoko , Akutsu Hidenori , Kondo Takahiko , Takahashi Yuji , Ban Tadanobu , Ito Chizuru , Toshimori Kiyotaka , Nakamura Akihiro , Ito Masahiko , Miyado Mami , Mekada Eisuke , Umezawa Akihiro
Published: August 2008

Membrane fusion is an essential step in the encounter of two nuclei from sex cells—sperm and egg—in fertilization. However, aside from the involvement of two molecules, CD9 and Izumo, the mechanism of fusion remains unclear. Here, we show that sperm–egg fusion is mediated by vesicles containing CD9 that are released from the egg and interact with sperm. We demonstrate that the CD9
−/−
eggs, which have a defective sperm-fusing ability, have impaired release of CD9-containing vesicles. We investigate the fusion-facilitating activity of CD9-containing vesicles by examining the fusion of sperm to CD9
−/−
eggs with the aid of exogenous CD9-containing vesicles. Moreover, we show, by examining the fusion of sperm to CD9
−/−
eggs, that hamster eggs have a similar fusing ability as mouse eggs. The CD9-containing vesicle release from unfertilized eggs provides insight into the mechanism required for fusion with sperm.
Unraveling the molecular basis of subunit specificity in P pilus assembly by mass spectrometry
Authors: Rose Rebecca J. , Verger Denis , Daviter Tina , Remaut Han , Paci Emanuele , Waksman Gabriel , Ashcroft Alison E. , Radford Sheena E.
Published: August 2008

P pili are multisubunit fibers essential for the attachment of uropathogenic
Escherichia coli
to the kidney. These fibers are formed by the noncovalent assembly of six different homologous subunit types in an array that is strictly defined in terms of both the number and order of each subunit type. Assembly occurs through a mechanism termed “donor-strand exchange (DSE)” in which an N-terminal extension (Nte) of one subunit donates a β-strand to an adjacent subunit, completing its Ig fold. Despite structural determination of the different subunits, the mechanism determining specificity of subunit ordering in pilus assembly remained unclear. Here, we have used noncovalent mass spectrometry to monitor DSE between all 30 possible pairs of P pilus subunits and their Ntes. We demonstrate a striking correlation between the natural order of subunits in pili and their ability to undergo DSE
in vitro
. The results reveal insights into the molecular mechanism by which subunit ordering during the assembly of this complex is achieved.
NGF and BDNF signaling control amyloidogenic route and Aβ production in hippocampal neurons
Authors: Matrone Carmela , Ciotti Maria Teresa , Mercanti Delio , Marolda Roberta , Calissano Pietro
Published: August 2008

Here, we report that interruption of NGF or BDNF signaling in hippocampal neurons rapidly activates the amyloidogenic pathway and causes neuronal apoptotic death. These events are associated with an early intracellular accumulation of PS1 N-terminal catalytic subunits and of APP C-terminal fragments and a progressive accumulation of intra- and extracellular Aβ aggregates partly released into the culture medium. The released pool of Aβ induces an increase of APP and PS1 holoprotein levels, creating a feed-forward toxic loop that might also cause the death of healthy neurons. These events are mimicked by exogenously added Aβ and are prevented by exposure to β- and γ-secretase inhibitors and by antibodies directed against Aβ peptides. The same cultured neurons deprived of serum die, but APP and PS1 overexpression does not occur, Aβ production is undetectable, and cell death is not inhibited by anti-Aβ antibodies, suggesting that hippocampal amyloidogenesis is not a simple consequence of an apoptotic trigger but is due to interruption of neurotrophic signaling.
China’s minorities without written scripts
Authors: Wang Jiayi , Postiglione Gerard A.
Published: August 2008

The Chinese state sees language as an essential determinant in ethnic minority schooling. The use of minority language as a medium of instruction is viewed as a way to increase attendance rates and strengthen socialization into a national ideology. However, the policies differ for those ethnic miorities with or without a commonly used written script. Among the minorities without a script are the 300,000 strong Dongxiang, an ethnic group with the lowest level of literacy and school access in China. There is virtually no systematic research on the role of language in school access for Chinese minority groups without a written script. In particular, there is a lack of analysis of the Dongxiang (and similar groups without a written script) learning and school discontinuation. This research aimed to identity the major difficulties in school based learning for the Dongxiang speaking children. Specifically, it explores local perspectives on how language and other factors are related to school enrolment and achievement. In order to accomplish this, the research combined a variety of data gathering methods, including survey questionnaires, open ended interviews, in-depth interviews, field visits, observations, and case studies to analyze the difficulties of language transition faced by Dongxiang ethnic minority children. The results reveal that although native language does not directly cause schoolchildren to discontinue their studies, it has an important indirect influence, especially on the girls. The research results also show that Dongxiang ethnic minority schoolchildren in the early years of schooling generally cannot understand their teachers’ Chinese teaching, which results in poor school performances, a decline of interest in learning, a frustrated sense of achievement, and a decline in self-respect. Many students drop out as part of a vicious cycle that sees a reproduction of poor conditions for learning.
Communication across languages and cultures
Authors: Sang Jian , Zhang Grace
Published: August 2008

Communication across languages and cultures is a markedly complex issue, and translation is more than just a careful linguistic transfer: it is a purposeful action designed to achieve the most effective result in a target group. Few studies have discussed the role of communicative intent in translation, and this paper is a small step towards filling the gap. The conceptual framework adopted in this study is Skopostheorie (Vermeer, 1989), a functionalist approach with an emphasis on communicative Skopos (purpose or aim), target texts and audiences. Using a method of contrastive comparison among effective, ineffective and controversial brand name translations from English to Mandarin Chinese, a systematic analysis is conducted regarding four translation strategies: phonetic appeal, suitable meaning, socio-cultural adaptation and consumer acceptance.

The findings demonstrate that any effective communication strategy needs to be in accordance with the communicative purpose of achieving an optimal impact upon the target group, and a successfully translated brand name should function in a target culture as effectively as the original name in a source culture. They suggest that a function oriented approach, rather than a source-text oriented approach, holds the key for a successful outcome. The most important thing is that translated brand names suit the needs of Chinese consumers.

This study is significant in that it challenges the traditional sound/meaning-based approach, and provides enriched understanding of the importance of achieving communicative purposes and optimal functional impact in a target group. The insights gained from this study add a vital conceptual dimension to the study of translation, and cross-cultural communication in general. In addition, the findings of this study may also provide practical assistance for an effective outcome in translation, and have pedagogical value in the teaching of translation. While the discussion in this study is based on Chinese data, the findings have implications for the translation of other languages.
Pre-imperial Chinese
Authors: Lu Dan
Published: August 2008

Along with the rapid economic development of China, the Chinese language is becoming a popular target language of learning in the world. A large number of learners try hard to learn Chinese. It is even believed that this situation is not a fad; instead it will continue and will make Chinese a world language. This paper is a conceptual and theoretical refutation of the possibility of such a happening. An analysis is made with occasional comparison to English from the perspectives of sociolinguistics and specific limitations of the Chinese language. It is argued that the concept of world language is related to the concept of language dominance. Although economic status and population of speakers may facilitate the promotion of a language, they are far from enough to make it possible. A language spreads on several more conditions. Among them are the broad acceptance of the traditional culture that a language represents, extensively scattered speech communities, a multiplicity of audio-visual publications of wide circulation, and more importantly, ease of learning and use. Evidence shows that none of these conditions currently exists for Chinese. In particular, the complexity and difficulty of the writing system handicap its spread.
Integrins control the positioning and proliferation of follicle stem cells in theDrosophilaovary
Authors: O'Reilly Alana M. , Lee Hsiu-Hsiang , Simon Michael A.
Published: August 2008

Adult stem cells are maintained in specialized microenvironments called niches, which promote self-renewal and prevent differentiation. In this study, we show that follicle stem cells (FSCs) in the Drosophila melanogaster ovary rely on cues that are distinct from those of other ovarian stem cells to establish and maintain their unique niche. We demonstrate that integrins anchor FSCs to the basal lamina, enabling FSCs to maintain their characteristic morphology and position. Integrin-mediated FSC anchoring is also essential for proper development of differentiating prefollicle cells that arise from asymmetrical FSC divisions. Our results support a model in which FSCs contribute to the formation and maintenance of their own niche by producing the integrin ligand, laminin A (LanA). Together, LanA and integrins control FSC proliferation rates, a role that is separable from their function in FSC anchoring. Importantly, LanA-integrin function is not required to maintain other ovarian stem cell populations, demonstrating that distinct pathways regulate niche–stem cell communication within the same organ.
Phosphorylation of the Arp2/3 complex is necessary to nucleate actin filaments
Authors: LeClaire Lawrence L. , Baumgartner Martin , Iwasa Janet H. , Mullins R. Dyche , Barber Diane L.
Published: August 2008

The actin-related protein 2/3 (Arp2/3) complex is the primary nucleator of new actin filaments in most crawling cells. Nucleation-promoting factors (NPFs) of the Wiskott-Aldrich syndrome protein (WASP)/Scar family are the currently recognized activators of the Arp2/3 complex. We now report that the Arp2/3 complex must be phosphorylated on either threonine or tyrosine residues to be activated by NPFs. Phosphorylation of the Arp2/3 complex is not necessary to bind NPFs or the sides of actin filaments but is critical for binding the pointed end of actin filaments and nucleating actin filaments. Mass spectrometry revealed phosphorylated Thr237 and Thr238 in Arp2, which are evolutionarily conserved residues. In cells, phosphorylation of only the Arp2 subunit increases in response to growth factors, and alanine substitutions of Arp2 T237 and T238 or Y202 inhibits membrane protrusion. These findings reveal an additional level of regulation of actin filament assembly independent of WASP proteins, and show that phosphorylation of the Arp2/3 complex provides a logical “or gate” capable integrating diverse upstream signals.
Self-eating from an ER-associated cup
Authors: Simonsen Anne , Stenmark Harald
Published: August 2008

Since the first morphological description of autophagosomes in the early 1960s, two critical questions have been a matter of intense investigation and debate: what is the origin of the autophagosomal membrane and how is it formed? A study by Axe et al. (E.L. Axe, S.A. Walker, M. Manifava, P. Chandra, H.L. Roderick, A. Habermann, G. Griffiths, and N.T. Ktistakis. 2008. J. Cell Biol. 182:685–701) provides evidence that cup-shaped protrusions from the endoplasmic reticulum, named omegasomes, serve as platforms for autophagosome biogenesis in mammalian cells.
Mutations of Nonconserved Residues within the Calcium Channel α1-interaction Domain Inhibit β-Subunit Potentiation
Authors: Gonzalez-Gutierrez Giovanni , Miranda-Laferte Erick , Naranjo David , Hidalgo Patricia , Neely Alan
Published: August 2008

Voltage-dependent calcium channels consist of a pore-forming subunit (CaVα1) that includes all the molecular determinants of a voltage-gated channel, and several accessory subunits. The ancillary β-subunit (CaVβ) is a potent activator of voltage-dependent calcium channels, but the mechanisms and structural bases of this regulation remain elusive. CaVβ binds reversibly to a conserved consensus sequence in CaVα1, the α1-interaction domain (AID), which forms an α-helix when complexed with CaVβ. Conserved aromatic residues face to one side of the helix and strongly interact with a hydrophobic pocket on CaVβ. Here, we studied the effect of mutating residues located opposite to the AID-CaVβ contact surface in CaV1.2. Substitution of AID-exposed residues by the corresponding amino acids present in other CaVα1 subunits (E462R, K465N, D469S, and Q473K) hinders CaVβ's ability to increase ionic-current to charge-movement ratio (I/Q) without changing the apparent affinity for CaVβ. At the single channel level, these CaV1.2 mutants coexpressed with CaVβ2a visit high open probability mode less frequently than wild-type channels. On the other hand, CaV1.2 carrying either a mutation in the conserved tryptophan residue (W470S, which impairs CaVβ binding), or a deletion of the whole AID sequence, does not exhibit CaVβ-induced increase in I/Q. In addition, we observed a shift in the voltage dependence of activation by +12 mV in the AID-deleted channel in the absence of CaVβ, suggesting a direct participation of these residues in the modulation of channel activation. Our results show that CaVβ-dependent potentiation arises primarily from changes in the modal gating behavior. We envision that CaVβ spatially reorients AID residues that influence the channel gate. These findings provide a new framework for understanding modulation of VDCC gating by CaVβ.
Preventing Voltage-dependent Gating of Anthrax Toxin Channels Using Engineered Disulfides
Authors: Anderson Damon S. , Blaustein Robert O.
Published: August 2008

The channel-forming component of anthrax toxin, (PA63)7, is a heptameric water-soluble protein at neutral pH, but under acidic conditions it spontaneously inserts into lipid bilayers to form a 14-stranded β-barrel ion-conducting channel. This channel plays a vital role in anthrax pathogenesis because it serves as a conduit for the membrane translocation of the two enzymatic components of anthrax toxin, lethal factor and edema factor. Anthrax channels open and close in response to changes in transmembrane voltage, a property shared by several other pore-forming toxins. We have discovered an unexpected phenomenon in cysteine-substituted channels that provides a window into this gating process: their normal voltage-dependent gating can be abolished by reaction with methanethiosulfonate (MTS) reagents or exposure to oxidizing conditions. Remarkably, this perturbation is seen with cysteines substituted at sites all along the ∼100 Å length of the channel's β-barrel. In contrast, reaction with N-ethylmaleimide, a thiol-reactive compound that does not form a mixed disulfide, does not affect gating at any of the sites tested. These findings, coupled with our biochemical detection of dimers, have led us to conclude that MTS reagents are catalyzing the formation of intersubunit disulfide bonds that lock channels in a conducting state, and that voltage gating requires a conformational change that involves the entire β-barrel.
A Carboxy-terminal Inter-Helix Linker As the Site of Phosphatidylinositol 4,5-Bisphosphate Action on Kv7 (M-type) K+ Channels
Authors: Hernandez Ciria C. , Zaika Oleg , Shapiro Mark S.
Published: August 2008

The regulation of M-type (KCNQ [Kv7]) K+ channels by phosphatidylinositol 4,5-bisphosphate (PIP2) has perhaps the best correspondence to physiological signaling, but the site of action and structural motif of PIP2 on these channels have not been established. Using single-channel recordings of chimeras of Kv7.3 and 7.4 channels with highly differential PIP2 sensitivities, we localized a carboxy-terminal inter-helix linker as the primary site of PIP2 action. Point mutants within this linker in Kv7.2 and Kv7.3 identified a conserved cluster of basic residues that interact with the lipid using electrostatic and hydrogen bonds. Homology modeling of this putative PIP2-binding linker in Kv7.2 and Kv7.3 using the solved structure of Kir2.1 and Kir3.1 channels as templates predicts a structure of Kv7.2 and 7.3 very similar to the Kir channels, and to the seven-β-sheet barrel motif common to other PIP2-binding domains. Phosphoinositide-docking simulations predict affinities and interaction energies in accord with the experimental data, and furthermore indicate that the precise identity of residues in the interacting pocket alter channel–PIP2 interactions not only by altering electrostatic energies, but also by allosterically shifting the structure of the lipid-binding surface. The results are likely to shed light on the general structural mechanisms of phosphoinositide regulation of ion channels.
Nitric Oxide–mediated Modulation of Synaptic Activity by Astrocytic P2Y Receptors
Authors: Mehta Bhupesh , Begum Gulnaz , Joshi Nanda B. , Joshi Preeti G.
Published: August 2008

We investigated the mechanism of synaptic suppression by P2Y receptors in mixed hippocampal cultures wherein networked neurons exhibit synchronized Ca2+ oscillations (SCO) due to spontaneous glutamatergic synaptic transmission. Pharmacological studies suggested that SCO suppression was mediated by P2Y2/P2Y4 receptors. Immunostaining studies and characterization of ATP/UTP-stimulated Ca2+ responses in solitary neurons and astrocytes revealed that the SCO attenuation was effectuated by astrocytes. We demonstrate that nitric oxide released from activated astrocytes causes synaptic suppression by inhibiting neurotransmitter release. Physiological concentrations of ATP and UTP evoked NO production in astrocytes. SCO suppression was considerably diminished by removal of extracellular NO by membrane-impermeable scavenger c-PTIO or by pretreatment of cells with nitric oxide synthase inhibitor L-NAME. The nitric oxide donor DETA/NO effectively suppressed the SCO. ATP/UTP inhibited KCl-induced exocytosis at presynaptic terminals in an NO-dependent manner. In the absence of exogenously added ATP/UTP, both the NO scavenger and NOS inhibitor enhanced the frequency of SCO, implying that astrocytes release NO during spontaneous synaptic activity and exert a suppressive effect. We report for the first time that under physiological conditions astrocytes use NO as a messenger molecule to modulate the synaptic strength in the networked neurons.
The center of quantum symmetric pair coideal subalgebras
Authors: Kolb Stefan , Letzter Gail
Published: August 2008

The theory of quantum symmetric pairs as developed by the second author is based on coideal subalgebras of the quantized universal enveloping algebra for a semisimple Lie algebra. This paper investigates the center of these coideal subalgebras, proving that the center is a polynomial ring. A basis of the center is given in terms of a submonoid of the dominant integral weights.
Direct mapping and alignment of protein sequences onto genomic sequence
Authors: Gotoh Osamu
Published: August 2008

Motivation: Finding protein-coding genes in a newly determined genomic sequence is the first step toward understanding the content written in the genome. Sequences of transcripts of homologous genes, if available, can considerably improve accuracy of prediction of genes and their structures, compared with that without such knowledge. As protein sequences are generally better conserved than nucleotide sequences, remote homologs can be used as templates, extending the applicability of evidence-based gene recognition methods. However, no tool seems to have been developed so far to simultaneously map and align a number of protein sequences on mammalian-sized genomic sequence.

Results: We have extended our computer program Spaln to accept protein sequences, as well as cDNA sequences, as queries. When the query and the target sequences are reasonably similar, e.g. between mammalian orthologs, Spaln runs one to two orders of magnitude faster than conventional approaches that rely on Blast search followed by dynamic-programming-based spliced alignment. Exon-level and gene-level accuracies of Spaln are significantly higher than those obtained by the best available methods of the same type, particularly when the query and the target are distantly related.

Availability:  Spaln is accessible online for a few species at http://www.genome.ist.i.kyoto-u.ac.jp/~aln_user. The source code is available for free for academic users from the same site.

Contact:  o.gotoh@i.kyoto-u.ac.jp

Supplementary information:  Supplementary data are available at Bioinformatics online.
Improving subcellular localization prediction using text classification and the gene ontology
Authors: Fyshe Alona , Liu Yifeng , Szafron Duane , Greiner Russ , Lu Paul
Published: August 2008

Motivation: Each protein performs its functions within some specific locations in a cell. This subcellular location is important for understanding protein function and for facilitating its purification. There are now many computational techniques for predicting location based on sequence analysis and database information from homologs. A few recent techniques use text from biological abstracts: our goal is to improve the prediction accuracy of such text-based techniques. We identify three techniques for improving text-based prediction: a rule for ambiguous abstract removal, a mechanism for using synonyms from the Gene Ontology (GO) and a mechanism for using the GO hierarchy to generalize terms. We show that these three techniques can significantly improve the accuracy of protein subcellular location predictors that use text extracted from PubMed abstracts whose references are recorded in Swiss-Prot.

Contact:  duane@cs.ualberta.ca

Supplementary information:  Supplementary data are available at Bioinformatics online.
Does Hyaluronic Acid Distribution in the Larynx Relate to the Newborn's Capacity for Crying?
Authors: Schweinfurth John M. , Thibeault Susan L.
Published: August 2008

Objectives/Hypothesis: The newborn is heavily dependent on voice communication and therefore has relatively higher vocal demands and expenditures than the adult, the loudness output per mass performance exceeds that of the adult, and the newborn larynx exhibits significant histological and biochemical differences. The neonatal larynx is capable of sustaining relatively greater pitch and loudness than the adult over longer periods of time. This ability may be related to a more compact arrangement of collagen within the lamina propria, less interstitial space, and a uniform distribution of hyaluronic acid (HA). As HA is the primary determinant of vocal fold viscosity and water content, the distribution of HA in the superficial portion of the neonatal vocal fold is hypothesized to be related to newborn crying endurance. Our objective was to examine the histological structure and the quantity and arrangement of HA within the lamina propria of the pediatric larynx and review the relevant physiology of hyaluronic acid and its impact on voice production.

Study Design: Histological and digital subtraction analysis.

Methods: Intact, neonatal larynges were sourced from fresh cadaveric specimens. Trichrome stain was used to assess the collagen content and location in the tissues. HA was stained using a colloidal iron staining technique with and without incubation with bovine testicular hyaluronidase. Average optical density was calculated in tissue before and after treatment with hyaluronidase, and the stain intensity ratio was calculated.

Results: A total of 14 larynges were suitable for examination, eight males and six females. Histological examination revealed a uniform appearance of the vocalfold without evidence of a distinct vocal ligament or layered structure. Colloidal iron staining revealed an even distribution of HA throughout the vocal fold with no significant difference between quadrants. Images of the colloidal iron‐stained tissue had a mean pixel intensity of 82 of 255. Slides of vocal fold tissue treated with hyaluronidase revealed a pixel intensity of 106 of 255 for a 22% mean difference in stain intensity (P < .01).

Conclusions: The identification of the layered structure of the adult lamina propria has raised a number of questions as to the development and purpose of the human larynx. Based on histological observations from the current study, possible explanations for the physiological differences include differences in the distribution and tissue concentration of HA and consequently dynamic viscosity, oncotic affinity for water, and less intercellular space in the superficial lamina propria.
The Effect of Famciclovir on Delayed Facial Paralysis After Acoustic Tumor Resection
Authors: Brackmann Derald E. , Fisher Laurel M. , Hansen Marlan , Halim Andrea , Slattery William H.
Published: August 2008

Objectives/Hypothesis: To determine the efficacy of prophylactic famciclovir to significantly reduce the percentage of patients experiencing postoperative delayed facial paresis.

Study Design: Prospective evaluation of facial nerve grade for two groups (treated and untreated) with famciclovir before and after surgery. All procedures were conducted by the same group of experienced neurotologists.

Methods: In a tertiary neurotologic private practice, the percentage of 1,023 patients with delayed facial paresis after undergoing microsurgical removal of unilateral acoustic tumor with no preoperative treatment was compared to the percentage of 530 patients with preoperative famciclovir treatment. Patients were prescribed famciclovir 500 mg BID for 3 days before surgery and 5 days postoperative. The House‐Brackmann Facial Nerve Grade was assessed prospectively at preoperative, immediate postoperative, and discharge from the hospital in both groups.

Results: Twenty‐five percent of the no famciclovir group experienced delayed facial palsy compared to 20% in the famciclovir group, a statistically significant difference (P < .04). The famciclovir group undergoing translabyrinthine craniotomy showed a significantly greater decrease in percentage of patients with delayed facial palsy than those undergoing middle fossa craniotomies (P < .003).

Conclusions: Famciclovir administered preoperatively and after craniotomies resulted in a smaller percentage of patients developing delayed facial weakness. We are continuing the routine use of famciclovir in perioperative acoustic tumor management and recommend that others do so.
Urocortin Expression in Mouse Cochlear Nucleus and Scarpa's Ganglion
Authors: Brawner James Travis , Thompson Ann
Published: August 2008

Objectives/Hypothesis: Clinical and basic studies have correlated tinnitus with stress. Although the etiology of tinnitus is unknown, the cochlear nucleus (CN) appears to play a role. To better understand the potential impact of stress on tinnitus and modulation of the central auditory system in general, the goal of the current study was to examine the presence and distribution of axon terminals containing urocortin in the CN of the mouse.

Study Design: Prospective description of histological findings.

Methods: Three different forms of urocortin were labeled in brainstem sections collected from 10 wild‐type mice by immunohistochemistry. Immunoreactive terminal fibers in the CN were digitally photographed, as well as reconstructed in the CN under a drawing tube attached to a light microscope.

Results: Specific staining was found in en passant type fibers scattered throughout the CN but situated mostly within the granule cell domains. Clusters of labeled fibers were observed in the nerve root. Labeled axons were observed in the three tracts known to carry olivocochlear fibers to the CN, as well as in the olivocochlear bundle itself. As the axons within the olivocochlear bundle departed the brainstem in the vestibular nerve, numerous labeled en passant fibers were observed among somata of the vestibular ganglion (Scarpa's). Centrally, labeled axons were followed from the CN to the lateral superior olive, an established source of urocortin‐positive efferents to the cochlea. These findings indicate that lateral olivocochlear efferents innervate the CN and Scarpa's ganglion, and also that urocortin is likely a neuromodulator in particular CN circuits.

Conclusions: The current study supports innervation of specific regions of the mouse CN and Scarpa's ganglion by neurons expressing urocortin. The innervation may be one substrate by which stress modulates particular CN processes. Further studies are necessary to establish the role of urocortin in CN models of tinnitus.
Follicular Dendritic Cell Sarcoma of the Head and Neck: Case Report and Literature Review
Authors: Chera Bhishamjit S. , Orlando Christine , Villaret Douglas B. , Mendenhall William M.
Published: August 2008

Objectives/Hypothesis: This article presents a case of a patient with follicular dendritic cell sarcoma (FDS), a rare neoplasm usually of the head and neck, and reviews the literature.

Study Design: Literature review.

Methods: A MEDLINE literature search was performed and the literature was reviewed.

Results: Our patient presented with an FDS that had been excised from the upper neck and recurred in a level V node. He was treated with neck dissection and postoperative irradiation and remains disease free 5.25 years after salvage treatment. The literature search yielded 67 case reports on FDS of the head and/or neck. Most patients were treated with surgery (94%). Twenty‐eight percent of patients received adjuvant radiotherapy; 18% received adjuvant chemotherapy. Fifty percent of patients were alive with no evidence of disease at last follow‐up; 9% died from disease.

Conclusions: We currently treat head and neck FDS with wide resection and postoperative radiotherapy.
Effect of Steroids, Acetyl‐cysteine and Calcium‐Activated Chloride Channel Inhibitors on Allergic Mucin Expression in Sinus Mucosa
Authors: Hauber Hans‐Peter , Steffen Armin , Goldmann Torsten , Vollmer Ekkehard , Hung Hsiao‐Ling , Wollenberg Barbara , Zabel Peter
Published: August 2008

Objectives/Hypothesis: Allergic inflammation of the upper airways is commonly associated with mucus hypersecretion. At present, there is no specific mucus regulating drug available. Our goal was to investigate the effect of glucocorticosteroids, acetyl‐cysteine (ACC), and calcium‐activated chloride channel (CLCA) inhibitors in a model of Th2 type cytokine induced mucin expression in human airway mucosa.

Study Design: Prospective.

Methods: Explanted tissue from human sinus mucosa was stimulated with interleukin (IL)‐4, IL‐9, or IL‐13. Different concentrations of dexamethasone, ACC, or CLCA inhibitors [niflumic acid (NFA) or MSI‐2216] were added to stimulated tissue. Epithelial mucin expression was quantified using periodic acid‐Schiff staining.

Results: IL‐4, IL‐9, and IL‐13 significantly increased epithelial mucin expression (P < .05). Dexamethasone reduced Th2 type cytokine induced mucin expression in a dose‐dependant manner being statistically significant at concentrations ≥4.0 μmol/L (IL‐4) and ≥40.0 μmol/L (IL‐9 and IL‐13) (P < .05). ACC had no significant effect on IL‐4 and IL‐13 induced mucin expression, whereas IL‐9 induced mucin expression was significantly decreased at concentrations ≥3.0 mmol/L (P < .05). NFA and MSI‐2216 decreased Th2 type cytokine induced mucin expression in a dose‐dependant manner. This effect was statistically significant at concentrations ≥100 μmol/L (NFA) and ≥50 μmol/L (MSI‐2216) (P < .05).

Conclusions: Th2 type cytokines can induce mucin expression in a model of explanted human airway mucosa. Th2 type cytokine induced mucin expression can be effectively reduced by either glucocorticosteroids or CLCA inhibitors ex vivo. Besides glucocorticosteroids CLCA inhibitors may offer an alternative therapeutic approach to treat allergic mucus hypersecretion.
Steroids in Otolaryngology
Authors: Cope Daron , Bova Ronaldo
Published: August 2008

Steroids are increasingly being used to treat a wide spectrum of otolaryngological disorders. It is important for ear‐nose‐throat surgeons to understand the short‐ and long‐term complications associated with steroid use. The aim of this study was to review the role of steroids in common ear‐nose‐throat disorders. Corticosteroid therapy has been shown to be effective in the management of idiopathic facial nerve palsy, allergic rhinitis, acute sinusitis, sinonasal inflammatory polyposis, and croup. The therapeutic efficacy of steroids in the management of Meniere's disease, sudden idiopathic sensorineural HL, chronic otitis media, and vestibular neuronitis remain controversial.
Topical Therapy in Anosmia: Relevance of Steroid‐Responsiveness
Authors: Stenner M , Vent J , Hüttenbrink K. ‐B. , Hummel T. , Damm M.
Published: August 2008

Objectives/Hypothesis: The use of steroids either systemically or topically is known as a common therapy in patients with anosmia. Nevertheless, investigations giving proof for the benefit of a topical therapy are very rare, and no prognostic factors are known. In our study, we for the first time evaluated the additional effect of a topical therapy not only with steroids but also with antibiotics after conventional pretreatment with oral steroids and propose the steroid‐responsiveness of an anosmia as a prognostic factor.

Study Design: Retrospective design.

Methods: We analyzed the data of 299 patients with olfactory dysfunction. Eighty‐nine underwent initial pretreatment with systemic steroids and presented data over a sufficient follow‐up time. In a second step all these patients were given a topical treatment in a head down forward position, namely either budesonid alone or in combination with neomycin. Primary outcome parameter was the threshold, discrimination and identification (TDI) score.

Results: Initial therapy with oral steroids changed the TDI from 15.5 to 18.7 in the means (P < .001). In general, leaving away systemic steroids while applying local therapy did not led to a reduction of the TDI (P < .001). Dividing up the patients into those suffering from a steroid‐responsive anosmia (SRA) and those without benefit from initial systemic steroids (non‐SRA), the topical treatment led to a significant difference between the two groups with benefit toward the non‐SRA group (P < .001). Regarding only the nonchronic rhinosinusitis anosmics, these findings became even more apparent. Furthermore, in non‐SRA patients we found even better results with steroids in combination with neomycin as a topical therapy. In this group, the combined topical therapy elevated the TDI for +2.1 points whereas topical steroids alone raised it only for +1.0 point.

Conclusions: The steroid‐responsiveness of anosmia seems to be a relevant prognostic indicator for a significant benefit of a topical therapy in general. Within all patients, the effect of an initial systemic therapy could be maintained by the adjacent topical treatment whereas in non‐SRA patients a topical therapy has a significant greater impact. Furthermore, antibiotics even seem to have an additional effect in this group. Different reasons, first of all an overwhelmed steroid resistance by additional antiinflammatory effects of antibiotics, e.g., the inhibition of apoptosis might play a role and are discussed.
Adenoid Cystic Carcinoma of the External Auditory Canal
Authors: Dong Fei , Gidley Paul W. , Ho Tang , Luna Mario A. , Ginsberg Lawrence E. , Sturgis Erich M.
Published: August 2008

Objective/Hypothesis: To describe the clinical history and outcome of patients with adenoid cystic carcinoma (ACC) of the external auditory canal (EAC).

Study Design: Retrospective case series.

Methods: A search of our institution's tumor registry identified 22 patients with ACC of the EAC. Both clinical histories and pathology slides, when available, were reviewed.

Results: The mean age at diagnosis was 42 years (median, 38.5 years), and the most common presenting complaints were otalgia and ear canal mass. Nine patients (41%) developed recurrences at a mean of 8 years (median, 8 years) after initial diagnosis, six died of ACC, and three were living with distant metastases at their last follow‐up. The mean duration of symptoms at the time of diagnosis was 7.7 years (range, 2–30 years) for patients who developed a recurrence after treatment vs. 1.2 year (range, 0–2 years) for patients who remained disease‐free (P = .137). Every patient who had recurrent disease reported a duration of symptoms of ≥2 years (P = .013), and every patient with a duration of symptoms >2 years recurred (P = .002). There was a trend for more local recurrences after limited resection (P = .061).

Conclusions: ACC of the EAC often recurs many years after definitive treatment. Although our sample size was too small to make definitive conclusions, we recommend aggressive local therapy with lateral temporal bone resection and adjuvant postoperative radiotherapy. In addition to successful local therapy, early diagnosis may be the only other effective means of preventing distant metastases.
Inhibition of human immunodeficiency virus-1 entry using vectors expressing a multimeric hammerhead ribozyme targeting the CCR5 mRNA
Authors: Nazari Reza , Ma Xue Zhong , Joshi Sadhna
Published: August 2008

Rz1–7is a multimeric hammerhead ribozyme targeting seven unique sites within the human CCR5 mRNA that is activein vitro. Mouse stem cell virus-based MGIN and human immunodeficiency virus (HIV)-1-based HEG1 vectors were used to express Rz1–7in a human CD4+T lymphoid cell line. Stable transductants expressed Rz1–7, which was further shown to be active, since CCR5 mRNA and surface CCR5 protein expression levels decreased. High levels of progeny virus were produced when the transduced cells were challenged with an X4-tropic HIV-1 (NL4-3) strain, suggesting that Rz1–7expression does not affect X4-tropic virus replication. When the transduced cells expressing Rz1–7were challenged with the R5-tropic HIV-1 (BaL) strain, 99–100 % inhibition of progeny virus production was observed for the duration of the experiment (∼2 months). When the cells were precultured for 2–3 months prior to HIV-1 infection, inhibition was more prominent in cells transduced with MGIN-Rz1–7than with HEG1-Rz1–7. Inhibition occurred at the level of viral entry, as no HIV-1 DNA could be detected. These results demonstrate that Rz1–7confers excellent inhibition of R5-tropic HIV-1 replication at the level of entry. Therefore, we anticipate that this multimeric ribozyme will be beneficial for HIV-1 gene therapy.
An infectious cDNA clone of a highly pathogenic porcine reproductive and respiratory syndrome virus variant associated with porcine high fever syndrome
Authors: Lv Jian , Zhang Jianwu , Sun Zhi , Liu Weiquan , Yuan Shishan
Published: August 2008

Since May 2006, a so-called ‘porcine high fever syndrome’ (PHFS) has spread all over China. The arterivirus porcine reproductive and respiratory syndrome virus (PRRSV) was believed to be the main causative agent, although the involvement of other pathogens was not formally excluded. The genome of a representative Chinese PRRSV strain, named JX143, was sequenced and used to develop infectious cDNA clones, pJX143 and pJX143M, with the latter containing an engineeredMluI site that served as a genetic marker. In various virological assays, the rescued viruses, vJX143 and vJX143M, were indistinguishable from their parental virus. Animal experiments showed that these recombinant viruses retained the high pathogenicity and induced the typical clinical symptoms observed during PHFS outbreaks. This is the first report describing infectious cDNA clones of this highly pathogenic PRRSV. Our results unambiguously fulfil Koch's postulates and define highly pathogenic PRRSV as the aetiological agent of PHFS in China.
Clathrin- and caveolae-independent entry of feline infectious peritonitis virus in monocytes depends on dynamin
Authors: Van Hamme Evelien , Dewerchin Hannah L. , Cornelissen Els , Verhasselt Bruno , Nauwynck Hans J.
Published: August 2008

Feline infectious peritonitis virus (FIPV), a coronavirus that causes a lethal chronic disease in cats, enters feline monocytes via endocytosis. In this study, the pathway of internalization is characterized by evaluating the effect of chemical inhibitors and/or expression of dominant-negative (DN) proteins on the percentage of internalized virions per cell and infection. Further, co-localization studies were performed to determine the involvement of certain cellular internalization proteins. FIPV is not internalized through a clathrin-mediated pathway, as chlorpromazine, amantadine and DN eps15 did not influence virus uptake and FIPV did not co-localize with clathrin. The caveolae-mediated pathway could be excluded based on the inability of genistein and DN caveolin-1 to inhibit virus uptake and lack of co-localization between FIPV and caveolin-1. Dynamin inhibitory peptide and DN dynamin effectively inhibited virus internalization. The inhibitor strongly reduced uptake to 20.3±1.1 % of uptake in untreated cells. In the presence of DN dynamin, uptake was 58.7±3.9 % relative to uptake in untransduced cells. Internalization of FIPV was slightly reduced to 85.0±1.4 and 87.4±6.1 % of internalization in control cells by the sterol-binding drugs nystatin and methyl-β-cyclodextrin, respectively. Rho GTPases were inhibited byClostridium difficiletoxin B, but no effect was observed. These results were confirmed with infection studies showing that infection was not influenced by chlorpromazine, amantadine and genistein, but was significantly reduced by dynamin inhibition and nystatin. In conclusion, these results indicate that FIPV enters monocytes through a clathrin- and caveolae-independent pathway that strongly depends on dynamin and is slightly sensitive to cholesterol depletion.
Hibiscus chlorotic ringspot virus coat protein inhibits trans-acting small interfering RNA biogenesis in Arabidopsis
Authors: Meng Chunying , Chen Jun , Ding Shou-wei , Peng Jinrong , Wong Sek-Man
Published: August 2008

Many plant and animal viruses have evolved suppressor proteins to block host RNA silencing at various stages of the RNA silencing pathways. Hibiscus chlorotic ringspot virus (HCRSV) coat protein (CP) is capable of suppressing the transiently expressed sense-RNA-induced post-transcriptional gene silencing (PTGS) in Nicotiana benthamiana. Here, constitutively expressed HCRSV CP from transgenic Arabidopsis was found to be able to rescue expression of the silenced GUS transgene. The HCRSV CP-transgenic Arabidopsis (line CP6) displayed several developmental abnormalities: elongated, downwardly curled leaves and a lack of coordination between stamen and carpel, resulting in reduced seed set. These abnormalities are similar to those observed in mutations of the genes of Arabidopsis RNA-dependent polymerase 6 (rdr6), suppressor of gene silencing 3 (sgs3), ZIPPY (zip) and dicer-like 4 (dcl4). The accumulation of microRNA (miRNA) miR173 remained stable; however, the downstream trans-acting small interfering RNA (ta-siRNA) siR255 was greatly reduced. Real-time PCR analysis showed that expression of the ta-siRNA-targeted At4g29770, At5g18040, PPR and ARF3 genes increased significantly, especially in the inflorescences. Genetic crossing of CP6 with an amplicon-silenced line (containing a potato virus X–green fluorescent protein transgene under the control of the 35S cauliflower mosaic virus promoter) suggested that HCRSV CP probably interfered with gene silencing at a step after RDR6. The reduced accumulation of ta-siRNA might result from the interference of HCRSV CP with Dicer-like protein(s), responsible for the generation of dsRNA in ta-siRNA biogenesis.
Functional studies of per os infectivity factors of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus
Authors: Song Jingjiao , Wang Ranran , Deng Fei , Wang Hualin , Hu Zhihong
Published: August 2008

A combined functional investigation on the four per os infectivity factors (PIFs) of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HearNPV) was conducted in this study. HearNPV bacmids with deletions of p74 (Ha20), pif1 (Ha111), pif2 (Ha132) and pif3 (Ha98) were constructed individually by homologous recombination in Escherichia coli cells. Repaired bacmids with respective pifs were also constructed. Western blot analyses revealed that all four PIFs were structural components of the envelope of HearNPV occlusion-derived virus (ODV). Electron microscopy showed that deletion of the pifs did not have any obvious effects on the morphology of the occlusion bodies (OBs). Bioassay analyses indicated that deletion of any of the above pifs resulted in loss of oral infectivity of OBs. The mixtures of the four pif-deletion mutants also resulted in deficiency of oral infectivity, implying that the four PIFs must be structural components of the same ODV to accomplish their function. Repairing of the respective genes into the pif-deletion bacmids could rescue the oral infectivity of the pif-deletion viruses. Calcofluor, which can damage the peritrophic membrane (PM), could not rescue the defects of the oral infectivity of the pif-deletion viruses, indicating that the PM is not likely to be the functional target of the PIFs.
Relevance of viral context and diversity of antigen-processing routes for respiratory syncytial virus cytotoxic T-lymphocyte epitopes
Authors: Johnstone Carolina , Guil Sara , Rico Miguel A. , García-Barreno Blanca , López Daniel , Melero José A. , Del Val Margarita
Published: August 2008

Antigen processing of respiratory syncytial virus (RSV) fusion (F) protein epitopes F85–93 and F249–258 presented to cytotoxic T-lymphocytes (CTLs) by the murine major histocompatibility complex (MHC) class I molecule Kdwas studied in different viral contexts. Epitope F85–93 was presented through a classical endogenous pathway dependent on the transporters associated with antigen processing (TAP) when the F protein was expressed from either RSV or recombinant vaccinia virus (rVACV). At least in cells infected with rVACV encoding either natural or cytosolic F protein, the proteasome was required for epitope processing. In cells infected with rVACV encoding the natural F protein, an additional endogenous TAP-independent presentation pathway was found for F85–93. In contrast, epitope F249–258 was presented only through TAP-independent pathways, but presentation was brefeldin A sensitive when the F protein was expressed from RSV, or mostly resistant when expressed from rVACV. Therefore, antigen-processing pathways with different mechanisms and subcellular localizations are accessible to individual epitopes presented by the same MHC class I molecule and processed from the same protein but in different viral contexts. This underscores both the diversity of pathways available and the influence of virus infection on presentation of epitopes to CTLs.