bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of antipsychotic treatment for schizophrenia: 6‐month results of the Pan‐European Schizophrenia Outpatient Health Outcomes (SOHO) study
Authors: Haro J. M. , Edgell E. T. , Novick D. , Alonso J. , Kennedy L. , Jones P. B. , Ratcliffe M. , Breier A. ,   SOHO advisory board
Published: February 2005

Objective:  To present the 6‐month outcomes associated with antipsychotic treatment of patients participating in the Schizophrenia Outpatient Health Outcomes (SOHO) study.

Method:  SOHO is a 3‐year, prospective, observational study of the health outcomes associated with antipsychotic treatment in 10 European countries. The study included over 10 000 out‐patients who were initiating or changing their antipsychotic medication.

Results:  Clinical Global Impression (CGI)‐severity and quality of life (QOL) scores improved in all treatment cohorts. There was a higher response in the CGI‐overall symptoms and in the CGI‐schizophrenia positive, negative, cognitive and depressive symptom scales in the olanzapine (Olz) and clozapine (Cloz) cohorts compared with other treatment cohorts. Changes were associated with an improvement in QOL.

Conclusion:  Patients starting Olz and Cloz tend to have better outcomes at 6 months than patients who start other antipsychotics in actual out‐patient clinical practice. The results should be interpreted conservatively because of the non‐randomized study design.
Association of the A/G Polymorphism at Position 49 in Exon 1 of CTLA‐4 with the Susceptibility to Unexplained Recurrent Spontaneous Abortion in the Chinese Population
Authors: Wang Xipeng , Lin Qide , Ma Zhengwen , Hong Yan , Zhao Aimin , Di Wen , Lu Peihua
Published: February 2005

Problem:  To investigate whether the A/G polymorphism at position 49 in exon 1 of cytotoxic T lymphocyte antigen‐4 (CTLA‐4) gene, which delivers a negative signal to T‐cell activation, confers the susceptibility to unexplained recurrent spontaneous abortion in the Chinese population.

Method of Study:  A total of 168 patients with unexplained recurrent spontaneous abortion (RSA), who were treated in the Renji Hospital affiliated to the Shanghai Second Medical University, were matched against 117 women with normal pregnancy history. Case–control study to compare the frequency of G/A alleles, AA/AG/GG genotypes and A + (AA + AG) /G+ (GG + AG) phenotypes of CTLA‐4 between RSA patients and controls were performed. After amplification of CTLA‐4 exon‐1 region by polymerase chain reaction (PCR), restriction fragment‐length polymorphism (RFLP) was used to detect the polymorphism at position 49 in exon‐1 of CTLA‐4 gene. Statistical significance was tested by SPSS software.

Results:  There were dissimilar distributions of G/A alleles, AA/AG/GG genotypes and A+/G+ phenotypes of CTLA‐4 between RSA patients and controls. The frequencies of G allele (P = 0.032) and GG genotype (P = 0.011) in RSA patients were significantly higher than those in controls, while the frequencies of AG genotype (P = 0.039) and A + (AA + AG) phenotype in RSA patients were decreased significantly (P = 0.011).

Conclusions:  Our findings suggest that A/G polymorphism in exon‐1 of CTLA‐4 is associated with the immunopathogenesis of RSA, and it confers susceptibility to RSA in Chinese population.
Ergänzende Verfahren in der Aknetherapie
Authors: Degitz Klaus , Plewig Gerd
Published: February 2005

Die moderne Aknetherapie beruht auf der Anwendung von antikomedogenen, antimikrobiellen und entzündungshemmenden Substanzen sowie Antiandrogenen. Ergänzend stehen traditionelle oder neu entwickelte Verfahren zur Verfügung. Hierzu zählen pharmakologische (Dapson, Zink) und physikalische (Phototherapie, photodynamische Therapie, Aknetoilette, Abrasiva) Prinzipien. Diese ergänzenden Verfahren werden hinsichtlich ihrer Wirksamkeit und ihres Stellenwertes innerhalb der Aknetherapie beurteilt.
Cosmetic results of histographically controlled excision of non‐melanoma skin cancer in the head and neck region
Authors: Eberle Franziska Carola , Schippert Wilfried , Trilling Birgit , Röcken Martin , Breuninger Helmut
Published: February 2005

Background: Beside the primary goal of complete eradication, the cosmetic result is an important aspect of the treatment of non‐melanoma skin tumors especially in the head and neck region.

Patients and Methods: From 1990 to 2000, we treated a total of 5,227 large basal cell carcinomas (BBC) and 1,189 squamous cell carcinomas (SCC) in the head and neck region by surgical excision in 4,239 inpatients at the Department of Dermatology, University of Tübingen. The procedure used in all patients was a conservative excision controlled by complete three dimensional histology of all margins (3D‐histology) and specifically targeted follow‐up surgery where required (histographic surgery). As part of the prospective tumor follow‐up, we asked the treating outdoor physician one and four years later to evaluate the results of our surgical procedures.

Results: Of the 5,565 follow‐up questionnaires sent back, 4,868 contained answers regarding the cosmetic result. The data from both answers were pooled. In 1,972 (40,5 %) patients the cosmetic result was evaluated as “excellent”, in 1,992 (40,9 %) as “good”, in 662 (13,6 %) as “satisfactory”, in 191 (3,9 %) as “mediocre” and in 51 (< 1,0 %) as “poor”. In 697 of the responses, the physician did not comment the cosmetic results or the patient was lost for follow up.

Conclusion: With respect to both long term safety and cosmetic outcome, tumor surgery with 3D‐histology of excisional margins has set very high quality standards in the treatment of non‐melanoma skin cancer of the head and neck area.
Comparative Analysis of Employment Services for People with Disabilities in Australia, Finland, and Sweden
Authors: O'Brien James , Dempsey Ian
Published: February 2005

Abstract Described and discussed are comparative employment policies and programs for people with intellectual and other disabilities in Australia, Finland, and Sweden. The dominant economic and social policies of many Western countries are such that they continue to place considerable pressure on the development and maintenance of employment programs for people with intellectual and physical disabilities, particularly for those with high support needs. The authors note that these policies often result in tension between the simultaneous achievement of person‐centered principles for people with disabilities and a desire for improved service efficiencies and accountability. In addition, a concern raised by specialists in all three countries is the demise of low skilled jobs, which traditionally have attracted people with intellectual disabilities. It is proposed that improving the level of education and training available for people with intellectual disabilities may improve their employment opportunities. In this vein, key aspects of these countries’ respective support programs were identified as an aid to policy‐makers and service providers reconciling the disparities between employment needs and opportunities.
Prostaglandin E2 potentiates a TTX‐resistant sodium current in rat capsaicin‐sensitive vagal pulmonary sensory neurones
Authors: Kwong Kevin , Lee Lu‐Yuan
Published: February 2005

Capsaicin‐sensitive vagal pulmonary neurones (pulmonary C neurones) play an important role in regulating airway function. During airway inflammation, the level of prostaglandin E2 (PGE2) increases in the lungs and airways. PGE2 has been shown to sensitize isolated pulmonary C neurones. The somatosensory correlate of the pulmonary C neurone, the small‐diameter nociceptive neurone of the dorsal root ganglion, contains a high percentage of tetrodotoxin‐resistant sodium currents (TTX‐R INa). Therefore, this study was carried out to determine whether these channel currents are involved in the PGE2‐induced sensitization of pulmonary C neurones. We used the perforated patch‐clamp technique to study the effects of PGE2 on the TTX‐R INa in acutely cultured capsaicin‐sensitive pulmonary neurones that were identified by retrograde labelling with a fluorescent tracer, DiI. We found that the pulmonary neurones sensitive to capsaicin had a higher percentage of TTX‐R INa than that of capsaicin‐insensitive pulmonary neurones. PGE2 exposure increased the evoked TTX‐R INa when experiments were performed at both room temperature and at 37°C. Furthermore, stimulation of the adenylyl cyclase/protein kinase A pathway with either forskolin or Sp‐5,6‐DCl‐cBiMPS potentiated the TTX‐R INa in a manner similar to that of PGE2. We conclude that these modulatory effects of PGE2 on TTX‐R INa play an important role in the sensitization of pulmonary C neurones.
Attenuated noradrenergic sensitivity during local cooling in aged human skin
Authors: Thompson Caitlin S. , Holowatz Lacy A. , Kenney W. Larry
Published: February 2005

Reflex‐mediated cutaneous vasoconstriction (VC) is impaired in older humans; however, it is unclear whether this blunted VC also occurs during local cooling, which mediates VC through different mechanisms. We tested the hypothesis that the sensitization of cutaneous vessels to noradrenaline (NA) during direct skin cooling seen in young skin is blunted in aged skin. In 11 young (18–30 years) and 11 older (62–76 years) men and women, skin blood flow was monitored at two forearm sites with laser Doppler (LD) flowmetry while local skin temperature was cooled and clamped at 24°C. Cutaneous vascular conductance (CVC; LD flux/mean arterial pressure) was expressed as percentage change from baseline (%ΔCVCbase). At one site, five doses of NA (10−10–10−2m) were sequentially infused via intradermal microdialysis during cooling while the other 24°C site served as control (Ringer solution + cooling). At control sites, VC due to cooling alone was similar in young versus older (−54 ± 5 versus−56 ± 3%ΔCVCbase, P= 0.46). In young, NA infusions induced additional dose‐dependent VC (10−8, 10−6, 10−4 and 10−2m: −70 ± 2, −72 ± 3, −78 ± 3 and −79 ± 4%ΔCVCbase; P < 0.05 versus control). In older subjects, further VC did not occur until the highest infused dose of NA (10−2m: −70 ± 5%ΔCVCbase; P < 0.05 versus control). When cutaneous arterioles are sensitized to NA by direct cooling, young skin exhibits the capacity to further constrict to NA in a dose‐dependent manner. However, older skin does not display enhanced VC capacity until treated with saturating doses of NA, possibly due to age‐associated decrements in Ca2+ availability or α2C‐adrenoceptor function.
Orifice Diameter Effects on Diesel Fuel Jet Flame Structure
Authors: Pickett Lyle M. , Siebers Dennis L.
Published: February 2005

The effects of orifice diameter on several aspects of diesel fuel jet flame structure were investigated in a constant-volume combustion vessel under heavy-duty direct-injection (DI) diesel engine conditions using Phillips research grade #2 diesel fuel and orifice diameters ranging from 45 μm to 180 μm. The overall flame structure was visualized with time-averaged OH chemiluminescence and soot luminosity images acquired during the quasi-steady portion of the diesel combustion event that occurs after the transient premixed burn is completed and the flame length is established. The lift-off length, defined as the farthest upstream location of high-temperature combustion, and the flame length were determined from the OH chemiluminescence images. In addition, relative changes in the amount of soot formed for various conditions were determined from the soot incandescence images. Combined with previous investigations of liquid-phase fuel penetration and spray development, the results show that air entrainment upstream of the lift-off length (relative to the amount of fuel injected) is very sensitive to orifice diameter. As orifice diameter decreases, the relative air entrainment upstream of the lift-off length increases significantly. The increased relative air entrainment results in a reduced overall average equivalence ratio in the fuel jet at the lift-off length and reduced soot luminosity downstream of the lift-off length. The reduced soot luminosity indicates that the amount of soot formed relative to the amount of fuel injected decreases with orifice diameter. The flame lengths determined from the images agree well with gas jet theory for momentum-driven nonpremixed turbulent flames.
Rich-Catalytic Lean-Burn Combustion for Low-Single-Digit NOx Gas Turbines
Authors: Smith Lance L. , Karim Hasan , Castaldi Marco J. , Etemad Shahrokh , Pfefferle William C. , Khanna Vivek , Smith Kenneth O.
Published: February 2005

A new rich-catalytic lean-burn combustion concept (trademarked by PCI as RCL) was tested at industrial gas turbine conditions, in Solar Turbines’ high-pressure (17 atm) combustion rig and in a modified Solar Turbines engine, demonstrating ultralow emissions of NOx<2 ppm and CO<10 ppm for natural gas fuel. For the single-injector rig tests, an RCL catalytic reactor replaced a single swirler/injector. NOx<3 ppm and CO<10 ppm were achieved over a 110°C operating range in flame temperature, including NOx<1 ppm at about 1350°C flame temperature. Combustion noise was less than 0.15% peak to peak. Four RCL catalytic reactors were then installed in a modified (single can combustor) engine. NOx emissions averaged 2.1 ppm over the allowable operating range for this modified engine, with CO<10 ppm and without combustion noise (less than 0.15% peak to peak).
A Study of Humidified Gas Turbines for Short-Term Realization in Midsized Power Generation—Part II: Intercooled Cycle Analysis and Final Economic Evaluation
Authors: Bartlett Michael A. , Westermark Mats O.
Published: February 2005

Humidified gas turbine (HGT) cycles are a group of advanced gas turbine cycles that use water–air mixtures as the working media. In this article, three known HGT configurations are examined in the context of short-term realization for small to mid-sized power generation: the steam injected gas turbine, the full-flow evaporative gas turbine, and the part-flow evaporative gas turbine. The heat recovery characteristics and performance potential of these three cycles are assessed, with and without intercooling, and a preliminary economic analysis is carried out for the most promising cycles.
Assessment of Rich-Burn, Quick-Mix, Lean-Burn Trapped Vortex Combustor for Stationary Gas Turbines
Authors: Straub Douglas L. , Casleton Kent H. , Lewis Robie E. , Sidwell Todd G. , Maloney Daniel J. , Richards George A.
Published: February 2005

This paper describes the evaluation of an alternative combustion approach to achieve low emissions for a wide range of fuel types. This approach combines the potential advantages of a staged rich-burn, quick-mix, lean-burn (RQL) combustor with the revolutionary trapped vortex combustor (TVC) concept. Although RQL combustors have been proposed for low-Btu fuels, this paper considers the application of an RQL combustor for high-Btu natural gas applications. This paper will describe the RQL/TVC concept and experimental results conducted at 10 atm (1013 kPa or 147 psia) and an inlet-air temperature of 644 K (700°F). The results from a simple network reactor model using detailed kinetics are compared to the experimental observations. Neglecting mixing limitations, the simplified model suggests that NOx and CO performance below 10 parts per million could be achieved in an RQL approach. The CO levels predicted by the model are reasonably close to the experimental results over a wide range of operating conditions. The predicted NOx levels are reasonably close for some operating conditions; however, as the rich-stage equivalence ratio increases, the discrepancy between the experiment and the model increases. Mixing limitations are critical in any RQL combustor, and the mixing limitations for this RQL/TVC design are discussed.
Heat Transfer in Two-Pass Rotating Rectangular Channels (AR=1:2 and AR=1:4) With 45 Deg Angled Rib Turbulators
Authors: Fu Wen-Lung , Wright Lesley M. , Han Je-Chin
Published: February 2005

This paper reports the heat transfer coefficients in two-pass rotating rectangular channels (AR=1:2 and AR=1:4) with rib roughened walls. Rib turbulators are placed on the leading and trailing walls of the two-pass channel at an angle of 45 deg to the flow direction. Four Reynolds numbers are considered from 5000 to 40 000. The rotation numbers vary from 0.0 to 0.3. The ribs have a 1.59 by 1.59 mm square cross section. The rib height-to-hydraulic diameter ratios e/Dh are 0.094 and 0.078 for AR=1:2 and AR=1:4, respectively. The rib pitch-to-height ratio P/e is 10 for both cases, and the inlet coolant-to-wall density ratio (Δρ/ρ) is maintained around 0.115. For each channel, two channel orientations are studied, 90 deg and 45 deg with respect to the plane of rotation. The results show that the rotation effect increased the heat transfer on trailing wall in the first pass, but reduced the heat transfer on the leading wall. For AR=1:4, the minimum heat transfer coefficient was 25% of the stationary value. However, the rotation effect reduced the heat transfer difference between the leading and trailing walls in the second pass.
Experimental Investigation of Oil Accumulation in Second Land of Internal Combustion Engines
Authors: Icoz T. , Dursunkaya Z.
Published: February 2005

Blowback of engine oil suspended in combustion gases, when the gas flows from the piston second land back into the combustion chamber, is believed to contribute to oil consumption and hydrocarbon emissions in internal combustion engines. Oil accumulation in the region between top and second compression rings is a factor that influences this phenomenon. The effects of individual parameters, such as oil film thickness and viscosity, however, have still not been understood. The present study was aimed at constructing an experimental setup to study the effect of oil film thickness on oil accumulation in the second land of internal combustion engines. Due to the inherent difficulties of experimentation on production engines, a modeled piston-cylinder assembly was constructed. Total oil accumulation in the modeled second land after a single piston stroke was measured and compared to oil consumption in operating engines.
Prediction of the Transient Thermodynamic Response of a Closed-Cycle Regenerative Gas Turbine
Authors: Korakianitis T. , Hochstein J. I. , Zou D.
Published: February 2005

Instantaneous-response and transient-flow component models for the prediction of the transient response of gas turbine cycles are presented. The component models are based on applications of the principles of conservation of mass, energy, and momentum. The models are coupled to simulate the system transient thermodynamic behavior, and used to predict the transient response of a closed-cycle regenerative Brayton cycle. Various system transients are simulated using: the instantaneous-response turbomachinery models coupled with transient-flow heat-exchanger models; and transient-flow turbomachinery models coupled with transient-flow heat-exchanger models. The component sizes are comparable to those for a solar-powered Space Station (radial turbomachinery), but the models can easily be expanded to other applications with axial turbomachinery. An iterative scheme based on the principle of conservation of working-fluid mass in the system is used to compute the mass-flow rate at the solar-receiver inlet during the transients. In the process the mass-flow rate of every component at every time step is also computed. Representative results of different system models are compared and discussed.
Investigation of Brush Seal Flow Characteristics Using Bulk Porous Medium Approach
Authors: Dogu Yahya
Published: February 2005

The flow behavior through a brush seal has been investigated by developing a flow analysis procedure with a porous medium approach. In order to increase the brush seal performance and use at more severe operating conditions, the complex flow in the bristle pack has become the major concern affecting seal features such as blow-down, hang-up, hysteresis, and bristle flutter. In this study, an axisymmetric CFD model is employed to calibrate anisotropic permeability coefficients for the bristle pack based on available experimental data: leakage, axial pressure on the rotor surface, and radial pressure on the backing plate. A simplified form of the force balance equation is introduced for the flow in the porous bristle pack. Different sets of permeability coefficients are defined for the fence height region below the seal backing plate and the upper region of the seal to correlate the different physical structures and behavior of these regions during operation. The upper region is subject to more stiffening due to backing plate support while the fence height region is free to spread and bend in the axial direction. It is found that flow resistance for the upper region should be 20% higher than the fence height region in order to match the experimental pressure within the bristle pack. Analysis results prove that the brush seal is well represented as a porous medium with this approach. Based on the model developed, characteristic flow and pressure fields in the entire bristle pack have been explored.
Experimental Investigation of a High Pressure Ratio Aspirated Fan Stage
Authors: Merchant Ali , Kerrebrock Jack L. , Adamczyk John J. , Braunscheidel Edward
Published: February 2005

The experimental investigation of an aspirated fan stage designed to achieve a pressure ratio of 3.4:1 at 1500 ft/s is presented in this paper. The low-energy viscous flow is aspirated from diffusion-limiting locations on the blades and flowpath surfaces of the stage, enabling a very high pressure ratio to be achieved in a single stage. The fan stage performance was mapped at various operating speeds from choke to stall in a compressor facility at fully simulated engine conditions. The experimentally determined stage performance, in terms of pressure ratio and corresponding inlet mass flow rate, was found to be in good agreement with the 3D viscous computational prediction, and in turn close to the design intent. Stage pressure ratios exceeding 3:1 were achieved at design speed, with an aspiration flow fraction of 3.5% of the stage inlet mass flow. The experimental performance of the stage at various operating conditions, including detailed flowfield measurements, are presented and discussed in the context of the computational analyses. The stage performance and operability at reduced aspiration flow rates at design and off-design conditions are also discussed.
Experimental Investigation of Diffuser Hub Injection to Improve Centrifugal Compressor Stability
Authors: Skoch Gary J.
Published: February 2005

Results from a series of experiments to investigate whether centrifugal compressor stability could be improved by injecting air through the diffuser hub surface are reported. The research was conducted in a 4:1 pressure ratio centrifugal compressor configured with a vane-island diffuser. Injector nozzles were located just upstream of the leading edge of the diffuser vanes. Nozzle orientations were set to produce injected streams angled at −8, 0, and +8 degrees relative to the vane mean camber line. Several injection flow rates were tested using both an external air supply and recirculation from the diffuser exit. Compressor flow range did not improve at any injection flow rate that was tested, and generally diminished as injection rate increased. Compressor flow range did improve slightly at zero injection due to the flow resistance created by injector openings on the hub surface. Resistance and flow range both increased as the injector orientation was turned toward radial. Leading edge loading and semivaneless space diffusion showed trends that are similar to those reported earlier from shroud surface experiments that did improve compressor range. Opposite trends are seen for hub injection cases where compressor flow range decreased. The hub injection data further explain the range improvement provided by shroud-side injection and suggest that stability factors cited in the discussion of shroud surface techniques are valid. The results also suggest that a different application of hub-side techniques may produce a range improvement in centrifugal compressors.
Response of a Laminar Separation Bubble to an Impinging Wake
Authors: Gostelow J. P. , Thomas R. L.
Published: February 2005

Laminar separation and transition phenomena were investigated experimentally in the wake-disturbed flow over a 2.4 m long flat plate. A controlled diffusion pressure distribution, representative of that on a compressor blade, was imposed but with sufficiently strong loading to cause laminar separation. Boundary layer velocity traverses were performed at several longitudinal stations. Wakes were generated upstream by a single rod, parallel to the leading edge, attached to a rotating disk mounted flush in the sidewall of the working section. Data are presented in the form of velocity traces and contours of velocity and turbulent intermittency. The results highlight the interaction between the incoming wake and the natural boundary layer, which features a long and thin laminar separation bubble; they demonstrate that wind tunnel experiments provide a good representation of boundary layer behavior under wake disturbances on turbomachinery blading. The calmed region behind the disturbance is a feature that is even stronger behind a wake interaction than behind a triggered turbulent spot. Intermittency values for the undisturbed flow in the separation bubble reattachment region are well represented by Narasimha’s universal intermittency distribution, lending support to the use of intermittency-based predictive routines in calculations of blade boundary layers.
Comparison of Fine-Scale Recombination Rates in Humans and Chimpanzees
Authors: Winckler Wendy , Myers Simon R. , Richter Daniel J. , Onofrio Robert C. , McDonald Gavin J. , Bontrop Ronald E. , McVean Gilean A. T. , Gabriel Stacey B. , Reich David , Donnelly Peter , Altshuler David
Published: February 2005

We compared fine-scale recombination rates at orthologous loci in humans and chimpanzees by analyzing polymorphism data in both species. Strong statistical evidence for hotspots of recombination was obtained in both species. Despite ∼99% identity at the level of DNA sequence, however, recombination hotspots were found rarely (if at all) at the same positions in the two species, and no correlation was observed in estimates of fine-scale recombination rates. Thus, local patterns of recombination rate have evolved rapidly, in a manner disproportionate to the change in DNA sequence.
Alteration of a Novel Dispensable Mitochondrial Ribosomal Small-Subunit Protein, Rsm28p, Allows Translation of Defective
COX2
mRNAs
Authors: Williams Elizabeth H. , Bsat Nada , Bonnefoy Nathalie , Butler Christine A. , Fox Thomas D.
Published: February 2005

Mutations affecting the RNA sequence of the first 10 codons of the
Saccharomyces cerevisiae
mitochondrial gene
COX2
strongly reduce translation of the mRNA, which encodes the precursor of cytochrome
c
oxidase subunit II. A dominant chromosomal mutation that suppresses these defects is an internal in-frame deletion of 67 codons from the gene
YDR494w
. Wild-type
YDR494w
encodes a 361-residue polypeptide with no similarity to proteins of known function. The epitope-tagged product of this gene, now named
RSM28
, is both peripherally associated with the inner surface of the inner mitochondrial membrane and soluble in the matrix. Epitope-tagged Rsm28p from Triton X-100-solubilized mitochondria sedimented with the small subunit of mitochondrial ribosomes in a sucrose gradient containing 500 mM NH
4
Cl. Complete deletion of
RSM28
caused only a modest decrease in growth on nonfermentable carbon sources in otherwise wild-type strains and enhanced the respiratory defect of the suppressible
cox2
mutations. The
rsm28
null mutation also reduced translation of an
ARG8

m

reporter sequence inserted at the
COX1
,
COX2
, and
COX3
mitochondrial loci. We tested the ability of
RSM28-1
to suppress a variety of
cox2
and
cox3
mutations and found that initiation codon mutations in both genes were suppressed. We conclude that Rsm28p is a dispensable small-subunit mitochondrial ribosomal protein previously undetected in systematic investigations of these ribosomes, with a positive role in translation of several mitochondrial mRNAs.
DNA-Binding Specificity of the IDI-4 Basic Leucine Zipper Factor of
Podospora anserina
Defined by Systematic Evolution of Ligands by Exponential Enrichment (SELEX)
Authors: Dementhon Karine , Saupe Sven J.
Published: February 2005

Heterokaryon incompatibility is a cell destruction process that occurs when fungal cells of unlike genotype fuse. In
Podospora anserina
, autophagy is engaged during cell death by incompatibility and a number of genes are induced at the transcriptional level. These genes are termed
idi
(induced during incompatibility) genes. Among these is
idi-4
, a gene encoding a basic leucine zipper (bZIP) factor. IDI-4 displays similarity to the GCN4/cross-pathway control (CPC) factors that control gene expression in response to amino acid starvation in fungi. The overexpression of
idi-4
triggers autophagy, leads to cell death, and also increases the expression of a number of
idi
genes, in particular
idi-7
, a gene involved in autophagy. Herein, we determined the in vitro target sequence of IDI-4. We have purified the recombinant IDI-4 bZIP domain and show that this 83-amino-acid-long peptide dimerizes in vitro and adopts an α-helical fold. We have then used a systematic evolution of ligands by exponential enrichment procedure to identify the sequence bound by the IDI-4 bZIP domain. The IDI-4 binding site consensus sequence corresponds to the ATGANTCAT pseudopalindrome. IDI-4 binding sites are present in the promoter region of the
idi-7
gene, and the bZIP IDI-4 peptide binds to the
idi-7
promoter in vitro. The identified IDI-4 consensus binding sequence is very similar to the GCN4/CPC binding site, raising the possibility of an interplay and/or partial functional redundancy between IDI-4 and CPC-type bZIP factors in fungi.
Improvement in Nuclear Entry and Transgene Expression of Baculoviruses by Disintegration of Microtubules in Human Hepatocytes
Authors: Salminen Mirka , Airenne Kari J. , Rinnankoski Rita , Reimari Jenni , Välilehto Outi , Rinne Johanna , Suikkanen Sanna , Kukkonen Sari , Ylä-Herttuala Seppo , Kulomaa Markku S. , Vihinen-Ranta Maija
Published: February 2005

Autographa californica
multicapsid nucleopolyhedrovirus (AcMNPV), a potent virus for mammalian cell gene delivery, possesses an ability to transduce mammalian cells without viral replication. We examined the role of the cellular cytoskeleton in the cytoplasmic trafficking of viral particles toward the nucleus in human hepatic cells. Microscopic studies showed that capsids were found in the nucleus after either viral inoculation or cytoplasmic microinjection of nucleocapsids. The presence of microtubule (MT) depolymerizing agents caused the amount of nuclear capsids to increase. Overexpression of p50/dynamitin, an inhibitor of dynein-dependent endocytic trafficking from peripheral endosomes along MTs toward late endosomes, did not significantly affect the amount of nuclear accumulation of nucleocapsids in the inoculated cells, suggesting that viral nucleocapsids are released into the cytosol during the early stages of the endocytic pathway. Moreover, studies with recombinant viruses containing the nuclear-targeted expression β-galactosidase gene (
β-gal
) showed a markedly increased level in the cellular expression of β-galactosidase in the presence of MT-disintegrating drugs. The maximal increase in expression at 10 h postinoculation was observed in the presence of 80 μM nocodazole or 10 μM vinblastine. Together, these data suggest that the intact MTs constitute a barrier to baculovirus transport toward the nucleus.
Identification and Characterization of Avihepadnaviruses Isolated from Exotic Anseriformes Maintained in Captivity
Authors: Guo Haitao , Mason William S. , Aldrich Carol E. , Saputelli Jeffry R. , Miller Darren S. , Jilbert Allison R. , Newbold John E.
Published: February 2005

Five new hepadnaviruses were cloned from exotic ducks and geese, including the Chiloe wigeon, mandarin duck, puna teal, Orinoco sheldgoose, and ashy-headed sheldgoose. Sequence comparisons revealed that all but the mandarin duck viruses were closely related to existing isolates of duck hepatitis B virus (DHBV), while mandarin duck virus clones were closely related to Ross goose hepatitis B virus. Nonetheless, the S protein, core protein, and functional domains of the Pol protein were highly conserved in all of the new isolates. The Chiloe wigeon and puna teal hepatitis B viruses, the two new isolates most closely related to DHBV, also lacked an AUG start codon at the beginning of their X open reading frame (ORF). But as previously reported for the heron, Ross goose, and stork hepatitis B viruses, an AUG codon was found near the beginning of the X ORF of the mandarin duck, Orinoco, and ashy-headed sheldgoose viruses. In all of the new isolates, the X ORF ended with a stop codon at the same position. All of the cloned viruses replicated when transfected into the LMH line of chicken hepatoma cells. Significant differences between the new isolates and between these and previously reported isolates were detected in the pre-S domain of the viral envelope protein, which is believed to determine viral host range. Despite this, all of the new isolates were infectious for primary cultures of Pekin duck hepatocytes, and infectivity in young Pekin ducks was demonstrated for all but the ashy-headed sheldgoose isolate.
Puma Lentivirus Is Controlled in Domestic Cats after Mucosal Exposure in the Absence of Conventional Indicators of Immunity
Authors: TerWee Julie A. , Yactor Jennifer K. , Sondgeroth Kerry S. , VandeWoude Sue
Published: February 2005

A high percentage of free-ranging pumas (
Felis concolor
) are infected with feline lentiviruses (puma lentivirus, feline immunodeficiency virus Pco [FIV-Pco], referred to here as PLV) without evidence of disease. PLV establishes productive infection in domestic cats following parenteral exposure but, in contrast to domestic cat FIV, it does not cause T-cell dysregulation. Here we report that cats exposed to PLV oro-nasally became infected yet rapidly cleared peripheral blood mononuclear cell (PBMC) proviral load in the absence of a correlative specific immune response. Two groups of four specific-pathogen-free cats were exposed to PLV via the mucosal (oro-nasal) or parenteral (i.v.) route. All animals were PBMC culture positive and PCR positive within 3 weeks postinfection and seroconverted without exhibiting clinical disease; however, three or four oro-nasally infected animals cleared circulating proviral DNA within 3 months. Antibody titers reached higher levels in animals that remained persistently infected. PLV antigen-induced proliferation was slightly greater in mucosally inoculated animals, but no differences were noted in cytotoxic T-lymphocyte responses or cytokine profiles between groups. The distribution of virus was predominantly gastrointestinal as opposed to lymphoid in all animals in which virus was detected at necropsy. Possible mechanisms for viral clearance include differences in viral fitness required for crossing mucosal surfaces, a threshold dose requirement for persistence, or an undetected sterilizing host immune response. This is the first report of control of a productive feline or primate lentivirus infection in postnatally exposed, seropositive animals. Mechanisms underlying this observation will provide clues to containment of immunodeficiency disease and could prompt reexamination of vaccine-induced immunity against human immunodeficiency virus and other lentiviruses.
Viral Replication-Independent Blockade of Dendritic Cell Maturation and Interleukin-12 Production by Human Herpesvirus 6
Authors: Smith Alison P. , Paolucci Clara , Di Lullo Giulia , Burastero Samuele E. , Santoro Fabio , Lusso Paolo
Published: February 2005

Human herpesvirus 6 (HHV-6) is a potentially immunosuppressive CD4
+
-T-lymphotropic betaherpesvirus that causes severe human thymocyte depletion in heterochimeric SCID-hu
thy/liv
mice and has been implicated as a potential cofactor in the progression of AIDS. However, the mechanisms of HHV-6-mediated immunosuppression have not yet been fully elucidated. We investigated the phenotypic and functional alterations induced by HHV-6 on peripheral blood-derived human dendritic cells (DC). The infection of DC with HHV-6 A or B was nonproductive, as revealed by calibrated real-time PCR measuring the accumulation of viral genome equivalents over time. Nevertheless, preexposure to HHV-6 markedly impaired the maturation of DC driven by gamma interferon and lipopolysaccharide, as shown by the reduced surface expression of major histocompatibility complex class I molecules, HLA-DR, CD40, and CD80. Moreover, HHV-6, but not the closely related betaherpesvirus HHV-7, dramatically suppressed the secretion of interleukin-12 (IL-12) p70 by DC, while the production of other cytokines that influence DC maturation, i.e., IL-10 and tumor necrosis factor alpha, was not significantly modified. Likewise, the secretion of the CC chemokines macrophage inflammatory protein 1β and RANTES was unaltered. Functionally, a pretreatment with HHV-6 impaired the ability of DC to stimulate allogeneic T-cell proliferation. Altogether, these data identify interference with the functional maturation of DC as a potential mechanism of HHV-6-mediated immunosuppression.
Maturation of Papillomavirus Capsids
Authors: Buck Christopher B. , Thompson Cynthia D. , Pang Yuk-Ying S. , Lowy Douglas R. , Schiller John T.
Published: February 2005

The papillomavirus capsid is a nonenveloped icosahedral shell formed by the viral major structural protein, L1. It is known that disulfide bonds between neighboring L1 molecules help to stabilize the capsid. However, the kinetics of inter-L1 disulfide bond formation during particle morphogenesis have not previously been examined. We have recently described a system for producing high-titer papillomavirus-based gene transfer vectors (also known as pseudoviruses) in mammalian cells. Here we show that papillomavirus capsids produced using this system undergo a maturation process in which the formation of inter-L1 disulfide bonds drives condensation and stabilization of the capsid. Fully mature capsids exhibit improved regularity and resistance to proteolytic digestion. Although capsid maturation for other virus types has been reported to occur in seconds or minutes, papillomavirus capsid maturation requires overnight incubation. Maturation of the capsids of human papillomavirus types 16 and 18 proceeds through an ordered accumulation of dimeric and trimeric L1 species, whereas the capsid of bovine papillomavirus type 1 matures into more extensively cross-linked forms. The presence of encapsidated DNA or the minor capsid protein, L2, did not have major effects on the kinetics or extent of capsid maturation. Immature capsids and capsids formed from L1 mutants with impaired disulfide bond formation are infectious but physically fragile. Consequently, capsid maturation is essential for efficient purification of papillomavirus-based gene transfer vectors. Despite their obvious morphological differences, mature and immature capsids are similarly neutralizable by various L1- and L2-specific antibodies.
The Ectodomain of Herpes Simplex Virus Glycoprotein H Contains a Membrane α-Helix with Attributes of an Internal Fusion Peptide, Positionally Conserved in the
Herpesviridae
Family
Authors: Gianni Tatiana , Martelli Pier Luigi , Casadio Rita , Campadelli-Fiume Gabriella
Published: February 2005

Human herpesviruses enter cells by fusion with target membranes, a process that requires three conserved glycoproteins: gB, gH, and gL. How these glycoproteins execute fusion is unknown. Neural network bioinformatics predicted a membrane α-helix contained within the ectodomain of herpes simplex virus (HSV) gH, positionally conserved in the gH of all examined herpesviruses. Evidence that it has attributes of an internal fusion peptide rests on the following lines of evidence. (i) The predicted membrane α-helix has the attribute of a membrane segment, since it transformed a soluble form of gD into a membrane-bound gD. (ii) It represents a critical domain of gH. Its partial or entire deletion, or substitution of critical residues inhibited HSV infectivity and fusion in the cell-cell fusion assay. (iii) Its replacement with the fusion peptide from human immunodeficiency virus gp41 or from vesicular stomatitis virus G partially rescued HSV infectivity and cell-cell fusion. The corresponding antisense sequences did not. (iv) The predicted α-helix located in the varicella-zoster virus gH ectodomain can functionally substitute the native HSV gH membrane α-helix, suggesting a conserved function in the human herpesviruses. We conclude that HSV gH exhibits features typical of viral fusion glycoproteins and that this property is likely conserved in the
Herpesviridae
family.
MyD88 Expression Is Required for Efficient Cross-Presentation of Viral Antigens from Infected Cells
Authors: Chen Margaret , Barnfield Christina , Näslund Tanja I. , Fleeton Marina N. , Liljeström Peter
Published: February 2005

While virus-infected dendritic cells (DCs) in certain instances have the capacity to activate naïve T cells by direct priming, cross-priming by DCs via the uptake of antigens from infected cells has lately been recognized as another important pathway for the induction of antiviral immunity. During cross-priming, danger and stranger signals play important roles in modulating immune responses. Analogous to what has been shown for other microbial infections, virally infected cells may contain several pathogen-associated molecular patterns that are recognized by Toll-like receptors (TLRs). We analyzed whether the efficient presentation of antigens derived from infected cells requires the usage of MyD88, which is a common adaptor molecule used by all TLRs. For this study, we used murine DCs that were wild type or deficient in MyD88 expression and fibroblasts that were infected with an alphavirus replicon to answer this question. Our results show that when DCs are directly infected, they are able to activate antigen-specific CD8+T cells in a MyD88-independent manner. In contrast, a strict requirement of MyD88 for cross-priming was observed when virally infected cells were used as a source of antigen in vitro and in vivo. This indicates that the effects of innate immunity stimulation via the MyD88 pathway control the efficiency of cross-presentation, but not direct presentation or DC maturation, and have important implications in the development of cytotoxic T lymphocyte responses against alphaviral replicon infections.
Basal and Reovirus-Induced Beta Interferon (IFN-β) and IFN-β-Stimulated Gene Expression Are Cell Type Specific in the Cardiac Protective Response
Authors: Stewart Michael J. , Smoak Kathleen , Blum Mary Ann , Sherry Barbara
Published: February 2005

Viral myocarditis is an important human disease, with a wide variety of viruses implicated. Cardiac myocytes are not replenished yet are critical for host survival and thus may have a unique response to infection. Previously, we determined that the extent of reovirus induction of beta interferon (IFN-β) and IFN-β-mediated protection in primary cardiac myocyte cultures was inversely correlated with the extent of reovirus-induced cardiac damage in a mouse model. Surprisingly, and in contrast, the IFN-β response did not determine reovirus replication in skeletal muscle cells. Here we compared the IFN-β response in cardiac myocytes to that in primary cardiac fibroblast cultures, a readily replenished cardiac cell type. We compared basal and reovirus-induced expression of IFN-β, IRF-7 (an interferon-stimulated gene [ISG] that further induces IFN-β), and another ISG (561) in the two cell types by using real-time reverse transcription-PCR. Basal IFN-β, IRF-7, and 561 expression was higher in cardiac myocytes than in cardiac fibroblasts. Reovirus T3D induced greater expression of IFN-β in cardiac myocytes than in cardiac fibroblasts but equivalent expression of IRF-7 and 561 in the two cell types (though fold induction for IRF-7 and 561 was higher in fibroblasts than in myocytes because of the differences in basal expression). Interestingly, while reovirus replicated to equivalent titers in cardiac myocytes and cardiac fibroblasts, removal of IFN-β resulted in 10-fold-greater reovirus replication in the fibroblasts than in the myocytes. Together the data suggest that the IFN-β response controls reovirus replication equivalently in the two cell types. In the absence of reovirus-induced IFN-β, however, reovirus replicates to higher titers in cardiac fibroblasts than in cardiac myocytes, suggesting that the higher basal IFN-β and ISG expression in myocytes may play an important protective role.
Immune Tolerance Split between Hepatitis B Virus Precore and Core Proteins
Authors: Chen Margaret , Sällberg Matti , Hughes Janice , Jones Joyce , Guidotti Luca G. , Chisari Francis V. , Billaud Jean-Noel , Milich David R.
Published: February 2005

The function of the hepatitis B virus (HBV) precore or HBeAg is largely unknown because it is not required for viral assembly, infection, or replication. However, the HBeAg does appear to play a role in viral persistence. It has been suggested that the HBeAg may promote HBV chronicity by functioning as an immunoregulatory protein. As a model of chronic HBeAg exposure and to examine the tolerogenic potential of the HBV precore and core (HBcAg) proteins, HBc/HBeAg-transgenic (Tg) mice crossed with T cell receptor (TCR)-Tg mice expressing receptors for the HBc/HBeAgs (i.e., TCR-antigen double-Tg pairs) were produced. This study revealed three phenotypes of HBe/HBcAg-specific T-cell tolerance: (i) profound T-cell tolerance most likely mediated by clonal deletion, (ii) T-cell clonal ignorance, and (iii) nondeletional T-cell tolerance mediated by clonal anergy and dependent on the structure, location, and concentration of the tolerogen. The secreted HBeAg is significantly more efficient than the intracellular HBcAg at eliciting T-cell tolerance. The split T-cell tolerance between the HBeAg and the HBcAg and the clonal heterogeneity of HBc/HBeAg-specific T-cell tolerance may have significant implications for natural HBV infection and especially for precore-negative chronic hepatitis.