bluuebunny/crossref_metadata_2025_split huggingface dataset:
Respiratory virus infection among hematopoietic cell transplant recipients: evidence for asymptomatic parainfluenza virus infection
Authors: Peck Angela J. , Englund Janet A. , Kuypers Jane , Guthrie Katherine A. , Corey Lawrence , Morrow Rhoda , Hackman Robert C. , Cent Anne , Boeckh Michael 
Published: May 2007

AbstractThe incidence of respiratory virus infection after hematopoietic cell transplantation (HCT) has probably been underestimated with conventional testing methods in symptomatic patients. This prospective study assessed viral infection episodes by testing weekly respiratory samples collected from HCT recipients, with and without symptoms reported by questionnaire, for 100 days after HCT. Samples were tested by culture and direct fluorescent antibody testing for respiratory syncytial virus (RSV), parainfluenza virus (PIV), and influenza A and B, and by quantitative reverse transcription–polymerase chain reaction for RSV, PIV, influenza A and B, and metapneumovirus (MPV). Of 122 patients, 30 (25%) had 32 infection episodes caused by RSV (5), PIV (17), MPV (6), influenza (3), RSV, or influenza (1). PIV, with a cumulative incidence estimate of 17.9%, was the only virus for which asymptomatic infection was detected. Lower virus copy number in patients with no or one symptom compared with 2 or more symptoms was found for all viruses in all patients (P < .001), with PIV infection having a similar virus-specific comparison (P = .004). Subclinical infection with PIV may help explain why infection-control programs that emphasize symptoms are effective against RSV and influenza but often not against PIV.
GrlJ, a Dictyostelium GABAB-like receptor with roles in post-aggregation development
Authors: Prabhu Yogikala , Müller Rolf , Anjard Christophe , Noegel Angelika A 
Published: May 2007

Abstract

Background
The G-protein-coupled receptor (GPCR) family represents the largest and most important group of targets for chemotherapeutics. They are extremely versatile receptors that transduce signals as diverse as biogenic amines, purins, odorants, ions and pheromones from the extracellular compartment to the interior via biochemical processes involving GTP-binding proteins. Until recently, the cyclic AMP receptors (cARs) were the only known G protein coupled receptors in Dictyostelium discoideum. The completed genome sequence revealed the presence of several families of GPCRs in Dictyostelium, among them members of the family 3 of GPCRs, the GABAB/glutamate like receptor family, which in higher eukaryotes is involved in neuronal signaling.

Results

D. discoideum has seventeen Family 3 members of GPCRs, denoted GrlA through GrlR. Their transcripts are detected throughout development with increased levels during early and late development. We have examined here GrlJ. GFP-tagged GrlJ localises to the plasmamembrane and to internal membranes. Inactivation of the grlJ gene leads to precocious development, and the mutant completes development ~6 hours earlier. Alterations were also noted at the slug stage and in spore formation. grlJ
- slugs were longer and broke apart several times on their way to culmination forming smaller but proportionate fruiting bodies. Spores from grlJ
- fruiting bodies were malformed and less viable, although the spore differentiation factors were synthesized and sensed normally. Expression of a GFP-tagged full length GrlJ rescued the phenotype.

Conclusion
Our data suggest that GrlJ acts at several stages of Dictyostelium development and that it is a negative regulator in Dictyostelium development.
A Cre-lox approach for transient transgene expression in neural precursor cells and long-term tracking of their progeny in vitro and in vivo
Authors: Geoffroy Cédric G , Raineteau Olivier 
Published: May 2007

Abstract
Background
Neural precursor cells (NPCs) can be isolated from various regions of the postnatal central nervous system (CNS). Manipulation of gene expression in these cells offers a promising strategy to manipulate their fate both in vitro and in vivo. In this study, we developed a technique that allows the transient manipulation of single/multiple gene expression in NPCs in vitro, and the long-term tracking of their progeny both in vitro and in vivo.

Results
In order to combine the advantages of transient transfection with the long-term tracking of the transfected cells progeny, we developed a new approach based on the cre-lox technology. We first established a fast and reliable protocol to isolate and culture NPCs as monolayer, from the spinal cord of neonatal transgenic Rosa26-YFP cre-reporter mice. These cells could be reliably transfected with single/multiple plasmids by nucleofection. Nucleofection with mono- or bicistronic plasmids containing the Cre recombinase gene resulted in efficient recombination and the long-term expression of the YFP-reporter gene. The transient cre-expression was non-toxic for the transfected cells and did not alter their intrinsic properties. Finally, we demonstrated that cre-transfected cells could be transplanted into the adult brain, where they maintained YFP expression permitting long-term tracking of their migration and differentiation.

Conclusion
This approach allows single/multiple genes to be manipulated in NPCs, while at the same time allowing long-term tracking of the transfected cells progeny to be analyzed both in vitro and in vivo.
Sequence variations in DNA repair gene XPCis associated with lung cancer risk in a Chinese population: a case-control study
Authors: Bai Yun , Xu Liang , Yang Xiaobo , Hu Zhibin , Yuan Jing , Wang Feng , Shao Minhua , Yuan Wentao , Qian Ji , Ma Hongxia , Wang Ying , Liu Hongliang , Chen Weihong , Yang Lin , Jing Guangfu , Huo Xiang , Chen Feng , Liu Yanhong , Jin Li , Wei Qingyi , Huang Wei , Shen Hongbing , Lu Daru , Wu Tangchun 
Published: May 2007

AbstractBackgroundThe nucleotide excision repair (NER) protein, xeroderma pigmentosum C (XPC), participates in recognizing DNA lesions and initiating DNA repair in response to DNA damage. Because mutations inXPCcause a high risk of cancer in XP patients, we hypothesized that inherited sequence variations inXPCmay alter DNA repair and thus susceptibility to cancer.MethodsIn this hospital-based case-control study, we investigated fiveXPCtagging, common single nucleotide polymorphisms (tagging SNPs) in 1,010 patients with newly diagnosed lung cancer and 1,011 matched cancer free controls in a Chinese population.ResultsIn individual tagging SNP analysis, we found that rs3731055AG+AAvariant genotypes were associated with a significantly decreased risk of lung adenocarcinoma [adjusted odds ratio (OR), 0.71; 95% confidence interval (CI), 0.56–0.90] but an increased risk of small cell carcinomas [adjusted OR, 1.79; 95% CI, 1.05–3.07]. Furthermore, we found that haplotypeACCCAwas associated with a decreased risk of lung adenocarcinoma [OR, 0.78; 95% CI, 0.62–0.97] but an increased risk of small cell carcinomas [OR, 1.68; 95% CI, 1.04–2.71], which reflected the presence of rs3731055Aallele in this haplotype. Further stratified analysis revealed that the protective effect of rs3731055AG+AAon risk of lung adenocarcinoma was more evident among young subjects (age ≤ 60) and never smokers.ConclusionThese results suggest that inherited sequence variations inXPCmay modulate risk of lung cancer, especially lung adenocarcinoma, in Chinese populations. However, these findings need to be verified in larger confirmatory studies with more comprehensively selected tagging SNPs.
Age standardisation – an indigenous standard?
Authors: Robson Bridget , Purdie Gordon , Cram Fiona , Simmonds Shirley 
Published: May 2007

AbstractThe study of inequities in health is a critical component of monitoring government obligations to uphold the rights of Indigenous Peoples. In Aotearoa/New Zealand the indigenous Māori population has a substantially younger age structure than the non-indigenous population making it necessary to account for age differences when comparing population health outcomes. An age-standardised rate is a summary measure of a rate that a population would have if it had a standard age structure. Changing age standards have stimulated interest in the potential impact of population standards on disparities data and consequently on health policy.This paper compares the age structure of the Māori and non-Māori populations with two standard populations commonly used in New Zealand: Segi's world and WHO world populations. The performance of these standards in Māori and non-Māori mortality data was then measured against the use of the Māori population as a standard. It was found that the choice of population standard affects the magnitude of mortality rates, rate ratios and rate differences, the relative ranking of causes of death, and the relative width of confidence intervals. This in turn will affect the monitoring of trends in health outcomes and health policy decision-making. It is concluded that the choice of age standard has political implications and the development and utilisation of an international indigenous population standard should be considered.
Identification of bacteria on the surface of clinically infected and non-infected prosthetic hip joints removed during revision arthroplasties by 16S rRNA gene sequencing and by microbiological culture
Authors: Dempsey Kate E , Riggio Marcello P , Lennon Alan , Hannah Victoria E , Ramage Gordon , Allan David , Bagg Jeremy 
Published: May 2007

AbstractIt has been postulated that bacteria attached to the surface of prosthetic hip joints can cause localised inflammation, resulting in failure of the replacement joint. However, diagnosis of infection is difficult with traditional microbiological culture methods, and evidence exists that highly fastidious or non-cultivable organisms have a role in implant infections. The purpose of this study was to use culture and culture-independent methods to detect the bacteria present on the surface of prosthetic hip joints removed during revision arthroplasties. Ten consecutive revisions were performed by two surgeons, which were all clinically and radiologically loose. Five of the hip replacement revision surgeries were performed because of clinical infections and five because of aseptic loosening. Preoperative and perioperative specimens were obtained from each patient and subjected to routine microbiological culture. The prostheses removed from each patient were subjected to mild ultrasonication to dislodge adherent bacteria, followed by aerobic and anaerobic microbiological culture. Bacterial DNA was extracted from each sonicate and the 16S rRNA gene was amplified with the universal primer pair 27f/1387r. All 10 specimens were positive for the presence of bacteria by both culture and PCR. PCR products were then cloned, organised into groups by RFLP analysis and one clone from each group was sequenced. Bacteria were identified by comparison of the 16S rRNA gene sequences obtained with those deposited in public access sequence databases. A total of 512 clones were analysed by RFLP analysis, of which 118 were sequenced. Culture methods identified species from the genera Leifsonia (54.3%), Staphylococcus (21.7%), Proteus (8.7%), Brevundimonas (6.5%), Salibacillus (4.3%), Methylobacterium (2.2%) and Zimmermannella (2.2%). Molecular detection methods identified a more diverse microflora. The predominant genus detected was Lysobacter, representing 312 (60.9%) of 512 clones analysed. In all, 28 phylotypes were identified: Lysobacter enzymogenes was the most abundant phylotype (31.4%), followed by Lysobacter sp. C3 (28.3%), gamma proteobacterium N4-7 (6.6%), Methylobacterium SM4 (4.7%) and Staphylococcus epidermidis (4.7%); 36 clones (7.0%) represented uncultivable phylotypes. We conclude that a diverse range of bacterial species are found within biofilms on the surface of clinically infected and non-infected prosthetic hip joints removed during revision arthroplasties.
Bonding of articular cartilage using a combination of biochemical degradation and surface cross-linking
Authors: Englert Carsten , Blunk Torsten , Müller Rainer , von Glasser Sabine Schulze , Baumer Julia , Fierlbeck Johann , Heid Iris M , Nerlich Michael , Hammer Joachim 
Published: May 2007

AbstractAfter trauma, articular cartilage often does not heal due to incomplete bonding of the fractured surfaces. In this study we investigated the ability of chemical cross-linkers to facilitate bonding of articular cartilage, either alone or in combination with a pre-treatment with surface-degrading agents. Articular cartilage blocks were harvested from the femoropatellar groove of bovine calves. Two cartilage blocks, either after pre-treatment or without, were assembled in a custom-designed chamber in partial apposition and subjected to cross-linking treatment. Subsequently, bonding of cartilage was measured as adhesive strength, that is, the maximum force at rupture of bonded cartilage blocks divided by the overlap area. In a first approach, bonding was investigated after treatment with cross-linking reagents only, employing glutaraldehyde, 1-ethyl-3-diaminopropyl-carbodiimide (EDC)/N-hydroxysuccinimide (NHS), genipin, or transglutaminase. Experiments were conducted with or without compression of the opposing surfaces. Compression during cross-linking strongly enhanced bonding, especially when applying EDC/NHS and glutaraldehyde. Therefore, all further experiments were performed under compressive conditions. Combinations of each of the four cross-linking agents with the degrading pre-treatments, pepsin, trypsin, and guanidine, led to distinct improvements in bonding compared to the use of cross-linkers alone. The highest values of adhesive strength were achieved employing combinations of pepsin or guanidine with EDC/NHS, and guanidine with glutaraldehyde. The release of extracellular matrix components, that is, glycosaminoglycans and total collagen, from cartilage blocks after pre-treatment was measured, but could not be directly correlated to the determined adhesive strength. Cytotoxicity was determined for all substances employed, that is, surface degrading agents and cross-linkers, using the resazurin assay. Taking the favourable cell vitality after treatment with pepsin and EDC/NHS and the cytotoxic effects of guanidine and glutaraldehyde into account, the combination of pepsin and EDC/NHS appeared to be the most advantageous treatment in this study. In conclusion, bonding of articular cartilage blocks was achieved by chemical fixation of their surface components using cross-linking reagents. Application of compressive forces and prior modulation of surface structures enhanced cartilage bonding significantly. Enzymatic treatment in combination with cross-linkers may represent a promising addition to current techniques for articular cartilage repair.
Crosstalk among Jak-STAT, Toll-like receptor, and ITAM-dependent pathways in macrophage activation
Authors: Hu Xiaoyu , Chen Janice , Wang Lu , Ivashkiv Lionel B 
Published: May 2007

AbstractMacrophage phenotype and activation are regulated by cytokines that use the Jak-STAT signaling pathway, microbial recognition receptors that include TLRs, and immunoreceptors that signal via ITAM motifs. The amplitude and qualitative nature of macrophage activation are determined by crosstalk among these signaling pathways. Basal ITAM signaling restrains macrophage responses to TLRs and other activating ligands, whereas strong ITAM signals synergize with the same ligands to activate cells strongly. Similarly, basal ITAM signaling augments IFN signaling and function of receptor activator of NF-κB, but extensive ITAM activation inhibits Jak-STAT signaling. Thus, intensity and duration of ITAM signaling determine whether ITAM-coupled receptors augment or attenuate TLR and Jak-STAT responses. IFN-γ synergizes with TLRs in part by suppressing TLR-induced feedback inhibition, mediated by IL-10 and Stat3, by a mechanism that depends on glycogen synthase kinase (GSK)3 regulation of AP-1 and CREB. IFN-γ suppresses TLR2 and TLR4 induction/activation of AP-1 by overlapping mechanisms that include regulation of MAPKs, GSK3-dependent suppression of DNA binding, and decreased Fos and Jun protein expression and stability. IFN-γ suppression of TLR-induced activation of AP-1 and downstream target genes challenges current concepts about the inflammatory role of AP-1 proteins in macrophage activation and is consistent with a role for AP-1 in the generation of noninflammatory osteoclasts. Jak-STAT, TLR, and ITAM pathways are basally active in macrophages and strongly induced during innate responses. Thus, signal transduction crosstalk is regulated in a dynamic manner, which differs under homeostatic and pathologic conditions, and dysregulation of signal transduction crosstalk may contribute to pathogenesis of chronic inflammatory diseases.
Refinement of the Iddm4 Diabetes Susceptibility Locus Reveals TCRVβ4 as a Candidate Gene
Authors: BLANKENHORN ELIZABETH P. , DESCIPIO CHERYL , RODEMICH LUCY , CORT LAURA , LEIF JEAN H. , GREINER DALE L. , MORDES JOHN P. 
Published: May 2007

Abstract:
Iddm4 is a dominant non‐major histocompatibility complex (MHC) determinant of diabetes susceptibility in BBDR rats treated with poly I:C, plus depletion of regulatory T cells. In congenic MHC‐identical normal WF rats, Iddm4d sensitively and specifically predicts induced diabetes. We report a new diabetes‐susceptible subcongenic line that carries Iddm4 in a < 2.6 megabase interval. Candidate genes include the T cell receptor β chain variable (TCRVβ) family. We found that TCRVβ4 in WF rats contains a stop codon, whereas 5/5 diabetes‐susceptible rat strains express TCRVβ4. We conclude that Iddm4‐mediated diabetes resistance in rats may be due to a recessive protective mutation in TCRVβ4.
Friction and wear performance of newly developed automotive bearing materials under boundary and mixed lubrication regimes
Authors: Kerr I , Priest M , Okamoto Y , Fujita M 
Published: May 2007

Global legislation on emissions and on recyclability of vehicles makes it necessary to run main and connecting rod bearing systems in automobile internal combustion (IC) engines with lower friction using lower oil flows and less viscous oils leading to more contact between bearing and shaft. At the same time lead must be removed from the system. In order to design suitable bearing materials for these new applications it is important to understand the frictional behaviour of candidate materials in a range of conditions covering the boundary and mixed regimes. Three plated plain bearing materials with overlays; a conventional lead based material, a newly developed bismuth based material, and a newly developed tin based system were tested on a tribometer specifically designed and built for this task to compare their performance in the boundary and mixed lubrication regimes under conditions that would be expected in an automobile engine. The resulting data was plotted as a series of Stribeck curves. The bismuth based material had slightly improved performance over the lead based material. The tin based material gave significantly higher friction, when compared with the other two materials. The wear properties of the materials were also tested and the variation of wear factor with testing time was plotted for each of the material at two different operating conditions. All materials experienced more severe wear in the initial stages of operation. The tin based material had the most severe wear, and showed signs of incipient melting of the overlay. The bismuth and lead based materials showed similar wear with the bismuth based material being superior under the most severe conditions, whereas the lead based material was superior under the other conditions tested. The bismuth material showed that it may be used as a suitable lead-free alternative material in IC engine applications under the conditions tested. The tin based material could not be used under such extreme conditions and failed because of thermal effects.
Abnormal film shapes in sliding elastohydrodynamic contacts lubricated by fatty alcohols
Authors: Yagi K , Vergne P 
Published: May 2007

This paper describes abnormal film shapes in point sliding contacts lubricated by fatty alcohols. The original film thickness features have appeared under moderate film thickness conditions using lauric alcohol and 1-dodecanol, which have a low viscosity and pressure-viscosity coefficient as lubricants. The film thickness is measured by white-light interferometry applied to glass disc-steel ball contacts. When the slide to roll ratio increases, the film thickness distribution changes. The thickness increase can lead to values several times higher than those measured under pure rolling conditions. Keeping the mean entrainment speed constant, despite the same absolute values of the slide to roll ratios, the film thickness distributions when the ball speed is higher differ from those when the disc speed is higher. The mechanisms that can explain such a new and unexpected EHL film behaviour are discussed using literature results and a simple thermal model that estimates the temperature increase at the solid surfaces and oil film. According to the results of the model, it is concluded that neither the temperature increase nor the temperature difference between the solid surfaces can explain the appearance of the abnormal film thickness features. However, the differences between the fluid responses suggest that the lubricant rheological behaviour contributes towards the observed phenomena.
Investigation of fundamental wear mechanisms at the piston ring and cylinder wall interface in internal combustion engines
Authors: Papadopoulos P , Priest M , Rainforth W. M. 
Published: May 2007

This research examined the cylinder liner-piston ring system simultaneously from the metallurgical and metrological standpoints, using specimens cut from real engine components (rings and liners), in order to identify the mild and severe wear mechanisms. Work has been conducted using a Plint TE77 high frequency friction machine. Metrological analysis was performed using stylus contacting profilometer. Metallurgical analysis of the samples was carried out using a JOEL JSM-6400 scanning electron microscope. In addition to wear, the coefficient of friction (μ) was recorded for every piston ring - cylinder liner pair so as to observe the transitions between mixed and boundary lubrication. This paper presents the results obtained using flame sprayed Mo-coated spheroidal graphite cast iron, which is an old piston ring coating and is not available anymore, and relatively new Federal Mogul CKS-36™ top compression rings tested against a grey cast iron cylinder liner tested at two different bulk oil temperatures (90 °C and 140 °C), two different pressures (3.9 MPa and 6.5 MPa) and with two different lubricants (SAE 0W20 with a Friction Modifier and SAE 15W40).