bluuebunny/crossref_metadata_2025 huggingface dataset:
Oxidase activity of a flavin‐dependent thymidylate synthase
Authors: Wang Zhen , Chernyshev Anatoly , Koehn Eric M. , Manuel Tony D. , Lesley Scott A. , Kohen Amnon
Published: April 2009

Flavin‐dependent thymidylate synthases (FDTS) catalyze the production of dTMP from dUMP and N5,N10‐methylene‐5,6,7,8‐tetrahydrofolate (CH2H4folate). In contrast to human and other classical thymidylate synthases, the activity of FDTS depends on a FAD coenzyme, and its catalytic mechanism is very different. Several human pathogens rely on this recently discovered enzyme, making it an attractive target for novel antibiotics. Like many other flavoenzymes, FDTS can function as an oxidase, which catalyzes the reduction of O2to H2O2, using reduced NADPH or other reducing agents. In this study, we exploit the oxidase activity of FDTS fromThermatoga maritimato probe the binding and release features of the substrates and products during its synthase activity. Results from steady‐state and single‐turnover experiments suggest a sequential kinetic mechanism of substrate binding during FDTS oxidase activity. CH2H4folate competitively inhibits the oxidase activity, which indicates that CH2H4folate and O2compete for the same reduced and dUMP‐activated enzymatic complex (FDTS–FADH2–NADP+–dUMP). These studies imply that the binding of CH2H4folate precedes NADP+release during FDTS activity. The inhibition constant of CH2H4folate towards the oxidase activity was determined to be rather small (2 μm), which indicates a tight binding of CH2H4folate to the FDTS–FADH2–NADP+–dUMP complex.
Surgical treatment of extrahepatic portal vein aneurysm: A case report and review of the literature
Authors: Ding Jiazeng , Peng Chenghong , Yan Jiqi , Jin Xiaotai , Kuang Jie , Li Hongwei
Published: April 2009

A portal vein aneurysm, first reported by Barzilai and Kleckner in 1956,1 is a rare clinical entity caused by portal hypertension or the malformation of veins. The frequent application of radiological imaging for diagnosis and screening of abdominal disorders accounts for the increasing number of case reports over the past 10 years; however, fewer than 60 cases have been reported in the English language literature to date. Herein we report a woman with an extrahepatic portal vein aneurysm, and present a review of literature relating to etiology, clinical significance and management strategies.
Management of intestinal atresia: Challenges and outcomes in a resource‐scarce region
Authors: Osifo Osarumwese David , Okolo Chukwunalu Jonathan
Published: April 2009

Aim:  Intestinal atresia is a common cause of intestinal obstruction in the newborn, associated with poor outcomes in many developing countries due to clinical sequelae of the lesion. Although outcomes have improved in many centers, the management requires facilities that are in short supply in developing countries. Here we report on five‐year outcomes, challenges, and experiences gained with the management of intestinal atresia in a resource‐scarce region and compare results with the preceding five years.

Methods:  A prospective study based on children diagnosed with intestinal atresia between July 2003 and June 2008 at the University of Benin Teaching Hospital, Benin City, Nigeria. Results were documented on a structured form and analyzed. The outcomes were compared between group A, comprising the preceding five years (July 1999–June 2003), and group B, comprising the present study group (July 2003–June 2008).

Results:  Forty‐three babies aged between 2 and 32 days (mean 11 ± 1.8 days), comprising 26 males and 17 females (ratio 1.5 : 1), were managed with intestinal atresia. Delayed presentation of these babies, which allowed fluid/electrolyte derangement, inanition, and established overwhelming resistant sepsis, as well as a lack of facilities, were major challenges resulting in poor outcomes (P < 0.0001). Aggressive resuscitation, resection of dilated proximal bowel segment allowing early commencement of oral feeds, enteroplasty, long use of broad spectrum antibiotics, improvised facilities to supply heat, and dedicated staff led to improved results. The number of survivors increased from 25% in group A to 75% in group B.

Conclusion:  This 75% survival rate could be increased further if there was provision of adequate facilities, especially total parenteral nutrition, and health awareness programs that result in early presentation.
The effect of strength training on the force of twitches evoked by corticospinal stimulation in humans
Authors: Carroll T. J. , Barton J. , Hsu M. , Lee M.
Published: April 2009

Aim:  Although there is considerable evidence that strength training causes adaptations in the central nervous system, many details remain unclear. Here we studied neuromuscular responses to strength training of the wrist by recording electromyographic and twitch responses to transcranial magnetic stimulation (TMS) and cervicomedullary stimulation of the corticospinal tract.

Methods:  Seventeen participants performed 4 weeks (12 sessions) of strength training for the radial deviator (RD) muscles of the wrist (n = 8) or control training without external load (n = 9). TMS recruitment curves were constructed from stimuli at five to eight intensities ranging between 15% below resting motor threshold and maximal stimulator output, both at rest and during isometric wrist extension (EXT) and RD at 10% and 50% of maximal voluntary contraction (MVC). Responses to weak TMS and cervicomedullary stimulation (set to produce a response of 10% maximal M wave amplitude during 10% MVC EXT contraction) were also compared at contraction strengths ranging from 10% to 75% MVC.

Results:  Isometric strength increased following strength training (10.7% for the RD MVC, 8.8% for the EXT MVC), but not control training. Strength training also significantly increased the amplitude of TMS‐ and cervicomedullary‐evoked twitches during low‐force contractions. Increases in the force‐generating capacity of the wrist extensor muscles are unlikely to account for this finding because training did not affect the amplitude of twitches elicited by supra‐maximal nerve stimulation.

Conclusion:  The data suggest that strength training induces adaptations that increase the net gain of corticospinal‐motor neuronal projections to the trained muscles.
An Eco‐hydro‐geomorphic Perspective to Modeling the Role of Climate in Catchment Evolution
Authors: Istanbulluoglu Erkan
Published: April 2009

Climate is the energizer of the landscape system. Geomorphic response of a catchment integrates a wide range of climate‐driven coupled biotic‐abiotic processes along topographic flow paths. As such, modeling the impacts of climate in landscape evolution requires a holistic approach, involving basin ecological and hydrological states, primitive in existing numerical models. To facilitate future model developments, a conceptual diagram of a holistic approach for modeling the role of climate in landscape evolution is presented. We identify hydrology and vegetation dynamics as critical components of future landscape evolution models and discuss how different runoff generation and simple vegetation growth‐death processes impact modeled catchment morphology and sediment yields. We illustrate fundamental differences observed in eco‐hydro‐geomorphic processes across climates using examples from the literature, and emphasize the importance of these differences on catchment evolution. The article concludes with the opinion that simplistic modeling approaches that capture the salient aspects of dominant climate‐soil‐vegetation‐erosion interactions observed in different climates should be adopted in landscape evolution models. This dominant‐process approach would also stimulate extensive process‐based field research, necessary for the merger of field and modeling perspectives in geomorphology.
Marginalized or Empowered? Street Reclaiming Strategies and the Situated Politics of Children's Mobilities
Authors: Fotel Trine
Published: April 2009

This article argues for the importance of acknowledging street reclaiming strategies and the situated politics of urban mobilities as a vital part of the production of urban space. Urban mobilities often form the basis of formal processes of political contestations as well as informal temporary appropriation strategies. As contemporary cities are often dominated by automobility, various other mobile practices tend to be marginalized in policy and planning. This article centres on an analysis of street reclaiming strategies and the situated politics of children's perspectives and experiences. These two themes provide unique examples of the dimensions of marginalization and empowerment in urban mobile practices. Issues of ‘the just city’ and dynamics of participatory planning are discussed as initiatives to attain more democratic urban mobilities.
A cell‐based H7N1 split influenza virion vaccine confers protection in mouse and ferret challenge models
Authors: Cox Rebecca J. , Major Diane , Hauge Solveig , Madhun Abdullah S. , Brokstad Karl A. , Kuhne Mirjam , Smith Jon , Vogel Frederick R. , Zambon Maria , Haaheim Lars R. , Wood John
Published: April 2009

Background  In recent years, several avian influenza subtypes (H5, H7 and H9) have transmitted directly from birds to man, posing a pandemic threat.

Objectives  We have investigated the immunogenicity and protective efficacy of a cell based candidate pandemic influenza H7 vaccine in pre‐clinical animal models.

Methods  Mice and ferrets were immunised with two doses of the split virus vaccine (12–24 μg haemagglutinin) with or without aluminium hydroxide adjuvant and challenged 3 weeks after second dose with the highly pathogenic A/chicken/Italy/13474/99 (H7N1) virus. The H7N1‐specific serum antibody response was also measured. After challenge, viral shedding, weight loss, disease signs and death (only mice) were recorded.

Results  Low‐to‐modest serum antibody titres were detected after vaccination. Nevertheless, the vaccine induced significant protection from disease after challenge with the wild‐type virus. In the murine lethal challenge model, vaccination effectively prevented death and, furthermore, formulation with adjuvant reduced excessive weight loss and viral shedding. In ferrets, vaccination reduced viral shedding and protected against systemic spread of the virus.

Conclusions  We have extended to the H7 subtype the finding that protective efficacy may not be directly correlated with the pre‐challenge levels of serum antibodies, a finding which could be of great importance in assessing the potential effectiveness of pandemic influenza vaccines.
Pi3K‐mTOR Signaling and AMOG Expression in Epilepsy‐associated Glioneuronal Tumors
Authors: Boer Karin , Troost Dirk , Timmermans Wendy , Van Rijen Peter C. , Spliet Wim G.M. , Aronica Eleonora
Published: April 2009

Gangliogliomas (GGs) and dysembryoplastic neuroepithelial tumors (DNTs) represent the most frequent type of neoplasms in pediatric medically intractable epilepsy. Several data suggest a pathogenetic relationship between GGs and other glioneuronal malformations of cortical development (MCDs), including activation of the Pi3K‐mTOR signaling pathway. To further reveal these pathogenetic similarities, we investigated immunocytochemically the expression of phosphorylated (p)‐PDK1, p‐AKT, p‐mTOR, p‐4E‐BP1, p‐eIF4G, p‐p70S6K and p‐S6, the effector proteins ERM (ezrin/radixin/moesin) and the pathway regulator AMOG (adhesion molecule on glia) in both GGs and DNTs. Components of the Pi3K‐mTOR signaling pathway were observed in a higher percentage of neuronal cells in GGs compared with control cortex. In DNTs, the expression of these components was low and comparable with the expression in control samples. Strong immunoreactivity for ERM was observed in GGs, but not in DNTs. Additionally, AMOG was strongly expressed within GGs (but not in DNTs) in CD34‐positive precursor cells. These findings support the previously suggested pathogenic relationship between GG and MCDs concerning activation of the Pi3K‐mTOR signaling pathway and suggest a different pathogenetic origin for DNTs. The strong expression of AMOG within the precursor cells of GG may represent an additional marker for the diagnostic evaluation of these glioneuronal lesions.
Cerebellar Cortical Demyelination in the Murine Cuprizone Model
Authors: Skripuletz Thomas , Bussmann Jens‐Heiko , Gudi Viktoria , Koutsoudaki Paraskevi N. , Pul Refik , Moharregh‐Khiabani Darius , Lindner Maren , Stangel Martin
Published: April 2009

In multiple sclerosis, demyelination occurs beside the white‐matter structures and in the cerebral and cerebellar cortex. We have previously shown that, in the cuprizone model, demyelination is present not only in the corpus callosum but also in the cerebral cortex. Here, we have performed a detailed analysis of the dynamics of de‐ and remyelination in the cerebellar cortex and white matter at nine timepoints in two cerebellar regions. To induce demyelination, C57BL/6 mice were fed with 0.2% cuprizone for 12 weeks followed by a recovery of 8 weeks. Both cortex and white‐matter structures were significantly demyelinated after 12 weeks of cuprizone feeding. Remyelination occurred after withdrawal of cuprizone but was less prominent in the more caudal cerebellar region. Microglia infiltration was prominent in all analyzed cerebellar areas, preceding demyelination by approximately 2–4 weeks, and was delayed in the more caudal cerebellar region. Astrogliosis was also seen but did not reach the extent observed in the cerebrum. In summary, cuprizone feeding provides an excellent model for the investigation of de‐ and remyelination processes in the cerebellar cortex and white matter. Furthermore, demyelination, microglia and astrocyte changes were different in the cerebellum as compared with the cerebrum, indicating region‐dependent pathomechanisms.
Colonization process of olive tissues by Verticillium dahliae and its in planta interaction with the biocontrol root endophyte Pseudomonas fluorescens PICF7
Authors: Prieto Pilar , Navarro‐Raya Carmen , Valverde‐Corredor Antonio , Amyotte Stefan G. , Dobinson Katherine F. , Mercado‐Blanco Jesús
Published: April 2009

The colonization process of Olea europaea by the defoliating pathotype of Verticillium dahliae, and the in planta interaction with the endophytic, biocontrol strain Pseudomonas fluorescens PICF7 were determined. Differential fluorescent protein tagging was used for the simultaneous visualization of P. fluorescens PICF7 and V. dahliae in olive tissues. Olive plants were bacterized with PICF7 and then transferred to V. dahliae‐infested soil. Monitoring olive colonization events by V. dahliae and its interaction with PICF7 was conducted using a non‐gnotobiotic system, confocal laser scanner microscopy and tissue vibratoming sections. A yellow fluorescently tagged V. dahliae derivative (VDAT‐36I) was obtained by Agrobacterium tumefaciens‐mediated transformation. Isolate VDAT‐36I quickly colonized olive root surface, successfully invaded root cortex and vascular tissues via macro‐ and micro‐breakages, and progressed to the aerial parts of the plant through xylem vessel cells. Strain PICF7 used root hairs as preferred penetration site, and once established on/in root tissues, hindered pathogen colonization. For the first time using this approach, the entire colonization process of a woody plant by V. dahliae is reported. Early and localized root surface and root endophytic colonization by P. fluorescens PICF7 is needed to impair full progress of verticillium wilt epidemics in olive.
COI and ITS2 sequences delimit species, reveal cryptic taxa and host specificity of fig‐associated Sycophila (Hymenoptera, Eurytomidae)
Authors: LI YANWEI , ZHOU XIN , FENG GUI , HU HAOYUAN , NIU LIMING , HEBERT PAUL D. N. , HUANG DAWEI
Published: April 2009

Although the genus Sycophila has broad host preferences, some species are specifically associated with figs as nonpollinator wasps. Because of their sexual dimorphism, morphological plasticity, cryptic mating behaviour and poorly known biology, species identifications are often uncertain. It is particularly difficult to match conspecific females and males. In this study, we employed two molecular markers, mitochondrial COI and nuclear ITS2, to identify Sycophila from six Chinese fig species. Morphological studies revealed 25 female and male morphs, while sequence results for both genes were consistent in supporting the presence of 15 species, of which 13 were host specialists and two used dual hosts. A single species of Sycophila was respectively found on four fig species, but six species were isolated from Ficus benjamina and a same number was reared from Ficus microcarpa. Sequence results revealed three male morphs in one species and detected two species that were overlooked by morphological analysis.
Characterization of 24 microsatellite markers in 11 species of fire ants in the genus Solenopsis (Hymenoptera: Formicidae)
Authors: ASCUNCE MARINA S. , BOUWMA ANDREW M. , SHOEMAKER DEWAYNE
Published: April 2009

The social parasite ant Solenopsis daguerrei infests colonies of several mound‐building fire ant species. Twenty‐four microsatellite markers were isolated from a repeat‐enriched genomic library of S. daguerrei. Eleven loci were polymorphic in this ant with two to six alleles per locus. Expected heterozygosity ranged from 0.0222 to 0.7940 among loci. Most microsatellites amplified successfully across the 11 Solenopsis species tested and will be useful for evolutionary genetic studies in this diverse ant group.
On the Eisenstein ideal for imaginary quadratic fields
Authors: Berger Tobias
Published: April 2009

For certain algebraic Hecke charactersχof an imaginary quadratic fieldFwe define an Eisenstein ideal in ap-adic Hecke algebra acting on cuspidal automorphic forms of GL2/F. By finding congruences between Eisenstein cohomology classes (in the sense of G. Harder) and cuspidal classes we prove a lower bound for the index of the Eisenstein ideal in the Hecke algebra in terms of the specialL-valueL(0,χ). We further prove that its index is bounded from above by thep-valuation of the order of the Selmer group of thep-adic Galois character associated toχ−1. This uses the work of R. Tayloret al. on attaching Galois representations to cuspforms of GL2/F. Together these results imply a lower bound for the size of the Selmer group in terms ofL(0,χ), coinciding with the value given by the Bloch–Kato conjecture.
Uniformly Diophantine numbers in a fixed real quadratic field
Authors: McMullen Curtis T.
Published: April 2009

The field$\mathbb {Q}(\sqrt {5})$contains the infinite sequence of uniformly bounded continued fractions$[\overline {1,4,2,3}], [\overline {1,1,4,2,1,3}], [\overline {1,1,1,4,2,1,1,3}], \ldots ,$and similar patterns can be found in$\mathbb {Q}(\sqrt {d})$for anyd>0. This paper studies the broader structure underlying these patterns, and develops related results and conjectures for closed geodesics on arithmetic manifolds, packing constants of ideals, class numbers and heights.
Pulsatile Stimulation Determines Timing and Specificity of NF-κB-Dependent Transcription
Authors: Ashall Louise , Horton Caroline A. , Nelson David E. , Paszek Pawel , Harper Claire V. , Sillitoe Kate , Ryan Sheila , Spiller David G. , Unitt John F. , Broomhead David S. , Kell Douglas B. , Rand David A. , Sée Violaine , White Michael R. H.
Published: April 2009

The nuclear factor κB (NF-κB) transcription factor regulates cellular stress responses and the immune response to infection. NF-κB activation results in oscillations in nuclear NF-κB abundance. To define the function of these oscillations, we treated cells with repeated short pulses of tumor necrosis factor–α at various intervals to mimic pulsatile inflammatory signals. At all pulse intervals that were analyzed, we observed synchronous cycles of NF-κB nuclear translocation. Lower frequency stimulations gave repeated full-amplitude translocations, whereas higher frequency pulses gave reduced translocation, indicating a failure to reset. Deterministic and stochastic mathematical models predicted how negative feedback loops regulate both the resetting of the system and cellular heterogeneity. Altering the stimulation intervals gave different patterns of NF-κB–dependent gene expression, which supports the idea that oscillation frequency has a functional role.
Learning from Errors
Authors: Laubichler Manfred D.
Published: April 2009

Freaks of Nature
. What Anomalies Tell Us About Development and Evolution / And What They Tell Us About Development and Evolution.
By Mark S. Blumberg
. Oxford University Press, New York, 2009. 340 pp. $22.95. ISBN 9780195322828. Oxford. 352 pp. £12.99. ISBN 9780199213054.

Blumberg presents examples of aberrant individuals as an underappreciated perspective on developmental and evolutionary processes.
Wingbeat Time and the Scaling of Passive Rotational Damping in Flapping Flight
Authors: Hedrick Tyson L. , Cheng Bo , Deng Xinyan
Published: April 2009

Flying animals exhibit remarkable capabilities for both generating maneuvers and stabilizing their course and orientation after perturbation. Here we show that flapping fliers ranging in size from fruit flies to large birds benefit from substantial damping of angular velocity through a passive mechanism termed flapping counter-torque (FCT). Our FCT model predicts that isometrically scaled animals experience similar damping on a per-wingbeat time scale, resulting in similar turning dynamics in wingbeat time regardless of body size. The model also shows how animals may simultaneously specialize in both maneuverability and stability (at the cost of efficiency) and provides a framework for linking morphology, wing kinematics, maneuverability, and flight dynamics across a wide range of flying animals spanning insects, bats, and birds.
Protein Dynamism and Evolvability
Authors: Tokuriki Nobuhiko , Tawfik Dan S.
Published: April 2009

The traditional view that proteins possess absolute functional specificity and a single, fixed structure conflicts with their marked ability to adapt and evolve new functions and structures. We consider an alternative, “avant-garde view” in which proteins are conformationally dynamic and exhibit functional promiscuity. We surmise that these properties are the foundation stones of protein evolvability; they facilitate the divergence of new functions within existing folds and the evolution of entirely new folds. Packing modes of proteins also affect their evolvability, and poorly packed, disordered, and conformationally diverse proteins may exhibit high evolvability. This dynamic view of protein structure, function, and evolvability is extrapolated to describe hypothetical scenarios for the evolution of the early proteins and future research directions in the area of protein dynamism and evolution.
Sending Signals Dynamically
Authors: Smock Robert G. , Gierasch Lila M.
Published: April 2009

Proteins mediate transmission of signals along intercellular and intracellular pathways and between the exterior and the interior of a cell. The dynamic properties of signaling proteins are crucial to their functions. We discuss emerging paradigms for the role of protein dynamics in signaling. A central tenet is that proteins fluctuate among many states on evolutionarily selected energy landscapes. Upstream signals remodel this landscape, causing signaling proteins to transmit information to downstream partners. New methods provide insight into the dynamic properties of signaling proteins at the atomic scale. The next stages in the signaling hierarchy—how multiple signals are integrated and how cellular signaling pathways are organized in space and time—present exciting challenges for the future, requiring bold multidisciplinary approaches.
Glioma-Derived Mutations in
IDH1
Dominantly Inhibit IDH1 Catalytic Activity and Induce HIF-1α
Authors: Zhao Shimin , Lin Yan , Xu Wei , Jiang Wenqing , Zha Zhengyu , Wang Pu , Yu Wei , Li Zhiqiang , Gong Lingling , Peng Yingjie , Ding Jianping , Lei Qunying , Guan Kun-Liang , Xiong Yue
Published: April 2009

Heterozygous mutations in the gene encoding isocitrate dehydrogenase-1 (
IDH1
) occur in certain human brain tumors, but their mechanistic role in tumor development is unknown. We have shown that tumor-derived
IDH1
mutations impair the enzyme's affinity for its substrate and dominantly inhibit wild-type IDH1 activity through the formation of catalytically inactive heterodimers. Forced expression of mutant
IDH1
in cultured cells reduces formation of the enzyme product, α-ketoglutarate (α-KG), and increases the levels of hypoxia-inducible factor subunit HIF-1α, a transcription factor that facilitates tumor growth when oxygen is low and whose stability is regulated by α-KG. The rise in HIF-1α levels was reversible by an α-KG derivative. HIF-1α levels were higher in human gliomas harboring an
IDH1
mutation than in tumors without a mutation. Thus, IDH1 appears to function as a tumor suppressor that, when mutationally inactivated, contributes to tumorigenesis in part through induction of the HIF-1 pathway.
Pgp3 Antibody Enzyme-Linked Immunosorbent Assay, a Sensitive and Specific Assay for Seroepidemiological Analysis of
Chlamydia trachomatis
Infection
Authors: Wills Gillian S. , Horner Patrick J. , Reynolds Rosy , Johnson Anne M. , Muir David A. , Brown David W. , Winston Alan , Broadbent Andrew J. , Parker David , McClure Myra O.
Published: April 2009

Understanding of the burden of
Chlamydia trachomatis
infection and its clinical sequelae is hampered by the absence of accurate, well-characterized tests using serological methods to determine past exposure to infection. An “in-house” immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) based on the
C. trachomatis
-specific antigen Pgp3 was produced and evaluated against three commercial ELISAs derived from the major outer membrane protein: the Medac pELISA plus, the Savyon SeroCT-IgG ELISA, and the Ani Labsystems IgG enzyme immunoassay. Sensitivities and specificities were determined using sera from both male and female patients (
n
= 356) for whom
C. trachomatis
had been detected in the lower genital tract at least 1 month prior to the testing of the sample and from 722
Chlamydia
-negative children aged 2 to 13 years. The Pgp3 ELISA was significantly more sensitive (57.9% [95% confidence interval {95% CI}, 52.7 to 62.9%]) than the Ani Labsystems (49.2% [95% CI, 44.0 to 54.3%];
P
= 0.003), SeroCT (47.2% [95% CI, 42.1 to 52.4%];
P
< 0.0005), and Medac (44.4% [95% CI, 39.3 to 49.6%];
P
< 0.0005) ELISAs. The Pgp3, Ani Labsystems, and SeroCT assays, but not the Medac assay, had significantly higher sensitivity for female specimens than for male specimens (73.8 versus 44.2%, 59.8 versus 40.5%, 55.5 versus 40%, and 45.7 versus 43.7%, respectively). For female patients, the Pgp3 assay was 14.0% (95% CI, 5.5 to 22.5%) more sensitive than the next most sensitive ELISA, the Ani Labsystems assay (
P
= 0.001). There was no significant difference in specificity between the Pgp3 (97.6% [95% CI, 96.2 to 98.6%]), Ani Labsystems (99% [95% CI, 97.7 to 99.6%]), SeroCT (97.2% [95% CI, 95.7 to 98.2%]), and Medac (96% [95% CI, 94.3 to 97.2%]) ELISAs. None of the ELISAs showed evidence of cross-reactivity with antibodies to
Chlamydia pneumoniae
.
Immunization with Oligomannose-Coated Liposome-Entrapped Dense Granule Protein 7 Protects Dams and Offspring fromNeospora caninumInfection in Mice
Authors: Nishikawa Yoshifumi , Zhang Houshuang , Ikehara Yuzuru , Kojima Naoya , Xuan Xuenan , Yokoyama Naoaki
Published: April 2009

The present study demonstrates that the subcutaneous administration ofNeospora caninumdense granule protein 7 (NcGRA7) entrapped in liposomes coated with mannotriose strongly induces the parasite-specific T-helper type 1 immune response and humoral antibody in mice. Although anti-NcGRA7 immunoglobulin G1 antibody production was induced in mice injected with NcGRA7 alone, the dams and offspring were never protected fromN. caninuminfection. The immunization of mice with liposome-entrapped NcGRA7 before pregnancy resulted in increased offspring survival and decreased the infection rates in the brains of dams after parasite infection at 6 to 9 days of gestation. In conclusion, oligomannose-coated liposome-entrapped NcGRA7 can be used as a new type of effective vaccine to control neosporosis.
Real-Time Quantitative PCR To Determine Chlamydial Load in Men and Women in a Community Setting
Authors: Wiggins R. , Graf S. , Low N. , Horner P. J.
Published: April 2009

We used a PCR method to quantify the loads of
Chlamydia trachomatis
organisms in self-collected urine and vulvovaginal swab (VVS) samples from 93 women and 30 men participating in the Chlamydia Screening Studies Project, a community-based study of individuals not seeking health care. For women, self-collected VVS had a higher mean chlamydial load (10,405 organisms/ml; 95% confidence interval [95% CI], 5,167 to 21,163 organisms/ml) than did first-void urines (FVU) (503 organisms/ml; 95% CI, 250 to 1,022 organisms/ml;
P
< 0.001). Chlamydial loads in female and male self-collected FVU specimens were similar (
P
= 0.634). The mean chlamydial load in FVU specimens decreased with increasing age in females and males. There was no strong statistical evidence of differences in chlamydial load in repeat male and female FVU specimens taken when patients attended for treatment a median of 23.5 (range, 14 to 62) and 28 (range, 13 to 132) days later, respectively, or in VVS taken a median of 35 (range, 14 to 217) days later. In this study, chlamydial load values for infected persons in the community who were not seeking treatment were lower than those published in other studies involving symptomatic patients attending clinical settings. This might have implications for estimates of the infectiousness of chlamydia. The results of this study provide a scientific rationale for preferring VVS to FVU specimens from women.
Simultaneous Identification of 14 Genital Microorganisms in Urine by Use of a Multiplex PCR-Based Reverse Line Blot Assay
Authors: Mckechnie Michelle L. , Hillman Richard , Couldwell Deborah , Kong Fanrong , Freedman Eleanor , Wang Hui , Gilbert Gwendolyn L.
Published: April 2009

The aim of this study was to develop and evaluate a sensitive method for the simultaneous identification of 14 urogenital potential pathogens. A multiplex PCR-based reverse line blot (mPCR/RLB) assay was developed to detect 14 urogenital pathogens or putative pathogens, namely
Trichomonas vaginalis
,
Streptococcus pneumoniae
,
Neisseria gonorrhoeae
,
Chlamydia trachomatis
,
Ureaplasma parvum
,
U. urealyticum
,
Gardnerella vaginalis
,
Haemophilus influenzae
, herpes simplex virus type 1 (HSV1) and HSV2,
N. meningitidis
,
Mycoplasma hominis
,
M. genitalium
, and adenovirus, using two species-specific primer pairs and probes for each. The method was validated using a reference strain or a well-characterized clinical isolate of each target organism and was found to be both sensitive and specific. The limits of detection for the mPCR/RLB assay varied among the 14 target organisms from 4.2 × 10
−1
to 7.0 × 10
−11
ng/μl of genomic DNA. There were no cross-reactions among any of the probes. This method was used to test 529 first-voided urine specimens from male patients with and without urethritis attending two Sydney sexual health clinics. One or more target species were detected in 193 (36%) subjects. Of 233 positive results, overall 216 (93%) were concordant between mPCR/RLB and a comparator method (culture and/or species-specific PCR), 9 were positive only by mPCR/RLB, and 8 were positive only by the comparator method. The mPCR/RLB method was an accurate, convenient, and inexpensive method for the detection of multiple potential pathogens in first-voided urine specimens from men.
Distribution of the
Escherichia coli
Common Pilus among Diverse Strains of Human Enterotoxigenic
E. coli
Authors: Blackburn Dana , Husband Amanda , Saldaña Zeus , Nada Rania A. , Klena John , Qadri Firdausi , Girón Jorge A.
Published: April 2009

The
Escherichia coli
common pilus (ECP) is produced by commensal and pathogenic
E. coli
strains. This pilus is unrelated to any of the known colonization factors (CFs) of enterotoxigenic
E. coli
(ETEC). In this study, we investigated the distribution and production of ECP among a collection of 136 human CF-positive and CF-negative ETEC strains of different geographic origins. The major pilus subunit gene,
ecpA
, was found in 109 (80%) of these strains, suggesting that it is widely distributed among ETEC strains. Phenotypic analysis of a subset of 43 strains chosen randomly showed that 58% of them produced ECP independently of the presence or absence of CFs, a percentage even higher than that of the most prevalent CFs. These data suggest an important role for ECP in the biology of ETEC, particularly in CF-negative strains, and in human infection.
Analysis of the Varicella-Zoster Virus IE62 N-Terminal Acidic Transactivating Domain and Its Interaction with the Human Mediator Complex
Authors: Yamamoto Shinobu , Eletsky Alexander , Szyperski Thomas , Hay John , Ruyechan William T.
Published: April 2009

The varicella-zoster virus major transactivator, IE62, contains a potent N-terminal acidic transcriptional activation domain (TAD). Our experiments revealed that the minimal IE62 TAD encompasses amino acids (aa) 19 to 67. We showed that the minimal TAD interacts with the human Mediator complex. Site-specific mutations revealed residues throughout the minimal TAD that are important for both activation and Mediator interaction. The TAD interacts directly with aa 402 to 590 of the MED25 subunit, and site-specific TAD mutations abolished this interaction. Two-dimensional nuclear magnetic resonance spectroscopy revealed that the TAD is intrinsically unstructured. Our studies suggest that transactivation may involve the TAD adopting a defined structure upon binding MED25.
The Herpes Simplex Virus Type 1 Glycoprotein D (gD) Cytoplasmic Terminus and Full-Length gE Are Not Essential and Do Not Function in a Redundant Manner for Cytoplasmic Virion Envelopment and Egress
Authors: Lee Hyun Cheol , Chouljenko Vladimir N. , Chouljenko Dmitry V. , Boudreaux Marc J. , Kousoulas K. G.
Published: April 2009

Herpes simplex virus type 1 (HSV-1) acquires its final envelope by budding into cytoplasmic vesicles thought to be derived from
trans
-Golgi network membranes. This process is facilitated by interactions among the carboxyl termini of viral glycoproteins and tegument proteins. To directly investigate the relative importance of the carboxyl terminus of glycoprotein D (gD) in the presence or absence of gE, a recombinant virus (gDΔct) was constructed to specify a truncated gD lacking the carboxy-terminal 29 amino acids. Furthermore, two additional recombinant viruses were constructed by mutating from ATG to CTG the initiation codons of gE (gEctg) or both gE and gM (gEctg+gMctg), causing lack of expression of gE or both gE and gM, respectively. A fourth mutant virus was constructed to specify the gEctg+gDΔct mutations. The replication properties of these viruses were compared to those of a newly constructed recombinant virus unable to express UL20 due to alteration of the two initiation codons of UL20 (UL20ctgctg). All recombinant viruses were constructed by using the double-Red, site-directed mutagenesis system implemented on the HSV-1(F) genome cloned into a bacterial artificial chromosome. The gEctg, gEctg+gMctg, gDΔct, and gEctg+gDΔct viruses produced viral plaques on African monkey kidney cells (Vero), as well as other cells, that were on average approximately 30 to 50% smaller than those produced by the wild-type virus HSV-1(F). In contrast, the UL20ctgctg virus produced very small plaques containing three to five cells, as reported previously for the ΔUL20 virus lacking the entire UL20 gene. Viral replication kinetics of intracellular and extracellular viruses revealed that all recombinant viruses produced viral titers similar to those produced by the wild-type HSV-1(F) virus intracellularly and extracellularly at late times postinfection, with the exception of the UL20ctgctg and ΔUL20 viruses, which replicated more than two-and-a-half logs less efficiently than HSV-1(F). Electron microscopy confirmed that all viruses, regardless of their different gene mutations, efficiently produced enveloped virions within infected cells, with the exception of the UL20ctgctg and ΔUL20 viruses, which accumulated high levels of unenveloped virions in the cytoplasm. These results show that the carboxyl terminus of gD and the full-length gE, either alone or in a redundant manner, are not essential in cytoplasmic virion envelopment and egress from infected cells. Similarly, gM and gE do not function alone or in a redundant manner in cytoplasmic envelopment and virion egress, confirming previous findings.
Bovine Coronavirus Nonstructural Protein 1 (p28) Is an RNA Binding Protein That Binds Terminal Genomic
cis
-Replication Elements
Authors: Gustin Kortney M. , Guan Bo-Jhih , Dziduszko Agnieszka , Brian David A.
Published: April 2009

Nonstructural protein 1 (nsp1), a 28-kDa protein in the bovine coronavirus (BCoV) and closely related mouse hepatitis coronavirus, is the first protein cleaved from the open reading frame 1 (ORF 1) polyprotein product of genome translation. Recently, a 30-nucleotide (nt)
cis
-replication stem-loop VI (SLVI) has been mapped at nt 101 to 130 within a 288-nt 5′-terminal segment of the 738-nt nsp1 cistron in a BCoV defective interfering (DI) RNA. Since a similar nsp1 coding region appears in all characterized groups 1 and 2 coronavirus DI RNAs and must be translated in
cis
for BCoV DI RNA replication, we hypothesized that nsp1 might regulate ORF 1 expression by binding this intra-nsp1 cistronic element. Here, we (i) establish by mutation analysis that the 72-nt intracistronic SLV immediately upstream of SLVI is also a DI RNA
cis
-replication signal, (ii) show by gel shift and UV-cross-linking analyses that cellular proteins of ∼60 and 100 kDa, but not viral proteins, bind SLV and SLVI, (SLV-VI) and (iii) demonstrate by gel shift analysis that nsp1 purified from
Escherichia coli
does not bind SLV-VI but does bind three 5′ untranslated region (UTR)- and one 3′ UTR-located
cis
-replication SLs. Notably, nsp1 specifically binds SLIII and its flanking sequences in the 5′ UTR with ∼2.5 μM affinity. Additionally, under conditions enabling expression of nsp1 from DI RNA-encoded subgenomic mRNA, DI RNA levels were greatly reduced, but there was only a slight transient reduction in viral RNA levels. These results together indicate that nsp1 is an RNA-binding protein that may function to regulate viral genome translation or replication but not by binding SLV-VI within its own coding region.
Human Metapneumovirus Establishes Persistent Infection in the Lungs of Mice and Is Reactivated by Glucocorticoid Treatment
Authors: Liu Yuru , Haas Debra L. , Poore Spencer , Isakovic Sanjin , Gahan Michelle , Mahalingam Suresh , Fu Zhen F. , Tripp Ralph A.
Published: April 2009

Human metapneumovirus (HMPV) has been identified as a worldwide agent of serious upper and lower respiratory tract infections in infants and young children. HMPV is second only to respiratory syncytial virus (RSV) as a leading cause of bronchiolitis, and, like RSV, consists of two major genotypes that cocirculate and vary among communities year to year. Children who have experienced acute HMPV infection may develop sequelae of wheezing and asthma; however, the features contributing to this pathology remain unknown. A possible mechanism for postbronchiolitis disease is that HMPV might persist in the lung providing a stimulus that could contribute to wheezing and asthma. Using immunohistochemistry to identify HMPV-infected cells in the lungs of mice, we show that HMPV mediates biphasic replication in respiratory epithelial cells then infection migrates to neuronal processes that innervate the lungs where the virus persists with no detectable infection in epithelial cells. After glucocorticoid treatment, the virus is reactivated from neural fibers and reinfects epithelial cells. The findings show that HMPV persists in neural fibers and suggest a mechanism for disease chronicity that has important implications for HMPV disease intervention strategies.
A Dominant-Negative Mutant of rab5 Inhibits Infection of Cells by Foot-and-Mouth Disease Virus: Implications for Virus Entry
Authors: Johns Helen L. , Berryman Stephen , Monaghan Paul , Belsham Graham J. , Jackson Terry
Published: April 2009

Foot-and-mouth disease virus (FMDV) can use a number of different integrins (αvβ1, αvβ3, αvβ6, and αvβ8) as receptors to initiate infection. Infection mediated by αvβ6 is known to occur by clathrin-mediated endocytosis and is dependent on the acidic pH within endosomes. On internalization, virus is detected rapidly in early endosomes (EE) and subsequently in perinuclear recycling endosomes (PNRE), but not in late endosomal compartments. Due to the extreme sensitivity of FMDV to acidic pH, it is thought that EE can provide a pH low enough for infection to occur; however, definitive proof that infection takes place from within these compartments is still lacking. Here we have investigated the intracellular transport steps required for FMDV infection of IBRS-2 cells, which express αvβ8 as their FMDV receptor. These experiments confirmed that FMDV infection mediated by αvβ8 is also dependent on clathrin-mediate endocytosis and an acidic pH within endosomes. Also, the effect on FMDV infection of dominant-negative (DN) mutants of cellular rab proteins that regulate endosomal traffic was examined. Expression of DN rab5 reduced the number of FMDV-infected cells by 80%, while expression of DN rab4 or DN rab7 had virtually no effect on infection. Expression of DN rab11 inhibited infection by FMDV, albeit to a small extent (∼35%). These results demonstrate that FMDV infection takes place predominantly from within EE and does not require virus trafficking to the late endosomal compartments. However, our results suggest that infection may not be exclusive to EE and that a small amount of infection could occur from within PNRE.
Primary Human Immunodeficiency Virus Type 1-Specific CD8+T-Cell Responses Induced by Myeloid Dendritic Cells
Authors: Colleton Bonnie A. , Huang Xiao-Li , Melhem Nada M. , Fan Zheng , Borowski Luann , Rappocciolo Giovanna , Rinaldo Charles R.
Published: April 2009

Induction of an antigenically broad and vigorous primary T-cell immune response by myeloid dendritic cells (DC) in blood and tissues could be important for an effective prophylactic or therapeutic vaccine to human immunodeficiency virus type 1 (HIV-1). Here we show that a primary CD8+T-cell response can be induced by HIV-1 peptide-loaded DC derived from blood monocytes of HIV-1-negative adults and neonates (moDC) and by Langerhans cells (LC) and interstitial, dermal-intestinal DC (idDC) derived from CD34+stem cells of neonatal cord blood. Optimal priming of single-cell gamma interferon (IFN-γ) production by CD8+T cells required CD4+T cells and was broadly directed to multiple regions of Gag, Env, and Nef that corresponded to known and predicted major histocompatibility complex class I epitopes. Polyfunctional CD8+T-cell responses, defined as single-cell production of more than one cytokine (IFN-γ, interleukin 2, or tumor necrosis factor alpha), chemokine (macrophage inhibitory factor 1β), or cytotoxic degranulation marker CD107a, were primed by moDC, LC, and idDC to HIV-1 Gag and reverse transcriptase epitopes, as well as to Epstein-Barr virus and influenza A virus epitopes. Thus, three major types of blood and tissue myeloid DC targeted by HIV-1, i.e., moDC, LC, and idDC, can prime multispecific, polyfunctional CD8+T-cell responses to HIV-1 and other viral antigens.
Identification of a Novel Determinant for Membrane Association in Hepatitis C Virus Nonstructural Protein 4B
Authors: Gouttenoire Jérôme , Castet Valérie , Montserret Roland , Arora Naveen , Raussens Vincent , Ruysschaert Jean-Marie , Diesis Eric , Blum Hubert E. , Penin François , Moradpour Darius
Published: April 2009

Nonstructural protein 4B (NS4B) plays an essential role in the formation of the hepatitis C virus (HCV) replication complex. It is a relatively poorly characterized integral membrane protein predicted to comprise four transmembrane segments in its central portion. Here, we describe a novel determinant for membrane association represented by amino acids (aa) 40 to 69 in the N-terminal portion of NS4B. This segment was sufficient to target and tightly anchor the green fluorescent protein to cellular membranes, as assessed by fluorescence microscopy as well as membrane extraction and flotation analyses. Circular dichroism and nuclear magnetic resonance structural analyses showed that this segment comprises an amphipathic α-helix extending from aa 42 to 66. Attenuated total reflection infrared spectroscopy and glycosylation acceptor site tagging revealed that this amphipathic α-helix has the potential to traverse the phospholipid bilayer as a transmembrane segment, likely upon oligomerization. Alanine substitution of the fully conserved aromatic residues on the hydrophobic helix side abrogated membrane association of the segment comprising aa 40 to 69 and disrupted the formation of a functional replication complex. These results provide the first atomic resolution structure of an essential membrane-associated determinant of HCV NS4B.
Sulfanylation of 1,3-dithiane anions by 5-(alkylsulfanyl)-1-phenyltetrazoles
Authors: Gudipati Venugopal , Bajpai Reena , Curran Dennis P.
Published: April 2009

An unusual reaction between 1,3-dithiane anions and by 5-(alkylsulfanyl)-1-phenyltetrazoles has been discovered in which the dithiane anion formally displaces the 1-phenyltetrazole ring from sulfur to provide a sulfanylated dithiane.
Comparison of the Effectiveness of Six and Two Acupuncture Point Regimens in Osteoarthritis of the Knee: A Randomised Trial
Authors: Taechaarpornkul Wirat , Suvapan Daranee , Theppanom Chaniya , Chanthipwaree Chantima , Chirawatkul Aroon
Published: April 2009

Background

Although substantial data have supported the effectiveness of acupuncture for treating knee osteoarthritis (OA), the number of points used has varied. The objective of this study was to compare the effectiveness of six and two acupuncture points in the treatment of knee OA.

Methods

A randomised trial of knee OA patients was conducted. Patients were randomly allocated into two groups of 35. The “six point group” received treatment at six acupuncture points, ST35, EX-LE4 ( Neixiyan), ST36, SP9, SP10 and ST34, while the “two point group” received treatment at just the first pair of points, ST35 and EX-LE4. Both groups received twice weekly electroacupuncture on 10 occasions. Electrical stimulation was carried out at low-frequency of 3 Hz to all points, with the intensity as high as tolerable. Both groups were allowed to take a 200 mg celecoxib capsule per day for intolerable pain. Patients were assessed at baseline, week 5, week 9 and week 13, using a Thai language version of the Western Ontario and McMaster Osteoarthritis Index (WOMAC). Global assessment of change after 10 treatments was also recorded.

Results

Acupuncture at both six and two acupuncture points was associated with significant improvement. Mean total WOMAC score at weeks 5 and 13 of patients in both groups showed no significant difference statistically (p = 0.75 and p = 0.51). Moreover, the number of celecoxib capsules taken, global assessment of global change and body weight change of both groups also showed no statistical difference.

Conclusion

This evidence suggests that electroacupuncture to two local points may be sufficient to treat knee OA, but in view of some limitations to this study further research is necessary before this can be stated conclusively.