bluuebunny/crossref_metadata_2025_split huggingface dataset:
Visuospatial working memory interference with recollections of trauma
Authors: Lilley Steven A. , Andrade Jackie , Turpin Graham , Sabin‐Farrell Rachel , Holmes Emily A. 
Published: February 2009

Objectives. Laboratory research using a working memory framework has shown modality‐specific reductions in image vividness and emotionality when concurrent tasks are performed while maintaining the image in consciousness. We extended this research to trauma images in a clinical population awaiting treatment for post‐traumatic stress symptoms.Design. A within‐subjects design was used, with each participant completing an imagery task under three concurrent task conditions: side‐to‐side eye‐movements, counting, and exposure only (no concurrent task).Method. Eighteen participants selected three images each, the images being those that were the most distressing from participants' trauma memories and most likely to intrude involuntarily. Participants gave baseline ratings of the vividness and emotionality of each of their trauma images. Each image was assigned to a condition. Each condition comprised 8 trials in which participants recollected the appropriate image for 8 s while performing eye‐movements, counting or no concurrent task, and then rated its vividness and emotionality. Follow‐up ratings were obtained by telephone 1 week later.Results. The eye‐movement task reduced vividness and emotionality of the trauma images relative to the counting task and exposure only, but did so only during the imagery period and not at follow‐up. The images were predominantly visual.Conclusions. Concurrent tasks matched to the modality of trauma images may provide a useful treatment aid for temporarily dampening emotional responses to recollections of trauma.
Coping with examinations: Exploring relationships between students' coping strategies, implicit theories of ability, and perceived control
Authors: Doron Julie , Stephan Yannick , Boiché Julie , Scanff Christine Le 
Published: February 2009

Background Relatively little is known about the contribution of students' beliefs regarding the nature of academic ability (i.e. their implicit theories) on strategies used to deal with examinations.Aims This study applied Dweck's socio‐cognitive model of achievement motivation to better understand how students cope with examinations. It was expected that students' implicit theories of academic ability would be related to their use of particular coping strategies to deal with exam‐related stress. Additionally, it was predicted that perceived control over exams acts as a mediator between implicit theories of ability and coping.Sample Four hundred and ten undergraduate students (263 males, 147 females), aged from 17 to 26 years old (M = 19.73, SD = 1.46) were volunteers for the present study.Methods Students completed measures of coping, implicit theories of academic ability, and perception of control over academic examinations during regular classes in the first term of the university year.Results Multiple regression analyses revealed that incremental beliefs of ability significantly and positively predicted active coping, planning, venting of emotions, seeking social support for emotional and instrumental reasons, whereas entity beliefs positively predicted behavioural disengagement and negatively predicted active coping and acceptance. In addition, analyses revealed that entity beliefs of ability were related to coping strategies through students' perception of control over academic examinations.Conclusions These results confirm that exam‐related coping varies as a function of students' beliefs about the nature of academic ability and their perceptions of control when approaching examinations.
Model of Solid State Transformations of Ductile Cast Iron GJS-600
Authors: Runser V. , Schulze V. 
Published: February 2009

Abstract
To quantify the way in which microstructure, stress, and distortion develop during the cooling of a ductile cast iron GJS-600 after its solidification and to predict the final thermomechanical properties of this material, it is necessary to identify all the metallurgical evolutions in solid state which occur after the casting in a sand mold. The present work deals with the influence of cooling conditions on the solid state transformations of a ductile cast iron austenitized for short periods and considering the initial carbon gradient. Numerical predictions for the modeling of the microstructure evolution and for the thermal strain development are validated with experimental results and show good agreement.
A Domestic cat X Chromosome Linkage Map and the Sex-LinkedorangeLocus: Mapping oforange, Multiple Origins and Epistasis Overnonagouti
Authors: Schmidt-Küntzel Anne , Nelson George , David Victor A , Schäffer Alejandro A , Eizirik Eduardo , Roelke Melody E , Kehler James S , Hannah Steven S , O'Brien Stephen J , Menotti-Raymond Marilyn 
Published: February 2009

AbstractA comprehensive genetic linkage map of the domestic cat X chromosome was generated with the goal of localizing the genomic position of the classic X-linked orange (O) locus. Microsatellite markers with an average spacing of 3 Mb were selected from sequence traces of the cat 1.9× whole genome sequence (WGS), including the pseudoautosomal region 1 (PAR1). Extreme variation in recombination rates (centimorgans per megabase) was observed along the X chromosome, ranging from a virtual absence of recombination events in a region estimated to be &gt;30 Mb to recombination frequencies of 15.7 cM/Mb in a segment estimated to be &lt;0.3 Mb. This detailed linkage map was applied to position the X-linked orange gene, placing this locus on the q arm of the X chromosome, as opposed to a previously reported location on the p arm. Fine mapping placed the locus between markers at positions 106 and 116.8 Mb in the current 1.9×-coverage sequence assembly of the cat genome. Haplotype analysis revealed potential recombination events that could reduce the size of the candidate region to 3.5 Mb and suggested multiple origins for the orange phenotype in the domestic cat. Furthermore, epistasis of orange over nonagouti was demonstrated at the genetic level.
Genetics and Lineage-Specific Evolution of a Lethal Hybrid Incompatibility Between Drosophila mauritiana and Its Sibling Species
Authors: Cattani M Victoria , Presgraves Daven C 
Published: February 2009

Abstract
The Dobzhansky–Muller model posits that intrinsic postzygotic reproductive isolation—the sterility or lethality of species hybrids—results from the evolution of incompatible epistatic interactions between species: favorable or neutral alleles that become fixed in the genetic background of one species can cause sterility or lethality in the genetic background of another species. The kind of hybrid incompatibility that evolves between two species, however, depends on the particular evolutionary history of the causative substitutions. An allele that is functionally derived in one species can be incompatible with an allele that is functionally derived in the other species (a derived-derived hybrid incompatibility). But an allele that is functionally derived in one species can also be incompatible with an allele that has retained the ancestral state in the other species (a derived-ancestral hybrid incompatibility). The relative abundance of such derived-derived vs. derived-ancestral hybrid incompatibilities is unknown. Here, we characterize the genetics and evolutionary history of a lethal hybrid incompatibility between Drosophila mauritiana and its two sibling species, D. sechellia and D. simulans. We show that a hybrid lethality factor(s) in the pericentric heterochromatin of the D. mauritiana X chromosome, hybrid lethal on the X (hlx), is incompatible with a factor(s) in the same small autosomal region from both D. sechellia and D. simulans, Suppressor of hlx [Su(hlx)]. By combining genetic and phylogenetic information, we infer that hlx-Su(hlx) hybrid lethality is likely caused by a derived-ancestral incompatibility, a hypothesis that can be tested directly when the genes are identified.
Identification of Receptor-Tyrosine-Kinase-Signaling Target Genes Reveals Receptor-Specific Activities and Pathway Branchpoints During Drosophila Development
Authors: Leatherbarrow John R , Halfon Marc S 
Published: February 2009

AbstractReceptor tyrosine kinases (RTKs) are an important family of signaling molecules with the unusual property that they are able to transduce their signals using the same downstream pathways. This has led to an unresolved debate as to whether individual receptors are interchangeable, or if each receptor can mediate specific downstream responses. To address this question, we have conducted a screen to identify target genes whose expression is differentially modulated by RTKs and their downstream pathway components. Using whole-mount in situ hybridization in Drosophila embryos exposed to constitutively active RTK pathway signaling, along with quantitative RT–PCR, we found that a significant fraction of target genes respond differentially in a spatial and/or quantitative manner. This includes differential responses to EGF receptor vs. fibroblast growth factor receptor signaling as well as to more downstream components such as Ras1 and pointed. We show that not only genes but also individual alternative transcripts can respond differently to signaling, and we present evidence that the differential responses can be mediated at the transcriptional level. Our results demonstrate that different RTKs can elicit distinct transcriptional responses, and the target genes obtained from our screen provide a valuable resource for further exploration of the mechanisms underlying this signaling specificity.
De Novo Identification of Single Nucleotide Mutations in Caenorhabditis elegans Using Array Comparative Genomic Hybridization
Authors: Maydan Jason S , Okada H Mark , Flibotte Stephane , Edgley Mark L , Moerman Donald G 
Published: February 2009

Abstract
Array comparative genomic hybridization (aCGH) has been used primarily to detect copy-number variants between two genomes. Here we report using aCGH to detect single nucleotide mutations on oligonucleotide microarrays with overlapping 50-mer probes. This technique represents a powerful method for rapidly detecting novel homozygous single nucleotide mutations in any organism with a sequenced reference genome.
Multiple SET Methyltransferases Are Required to Maintain Normal Heterochromatin Domains in the Genome ofDrosophila melanogaster
Authors: Brower-Toland Brent , Riddle Nicole C , Jiang Hongmei , Huisinga Kathryn L , Elgin Sarah C R 
Published: February 2009

AbstractMethylation of histone H3 lysine 9 (H3K9) is a key feature of silent chromatin and plays an important role in stabilizing the interaction of heterochromatin protein 1 (HP1) with chromatin. Genomes of metazoans such as the fruit fly Drosophila melanogaster generally encode three types of H3K9-specific SET domain methyltransferases that contribute to chromatin homeostasis during the life cycle of the organism. SU(VAR)3-9, dG9a, and dSETDB1 all function in the generation of wild-type H3K9 methylation levels in the Drosophila genome. Two of these enzymes, dSETDB1 and SU(VAR)3-9, govern heterochromatin formation in distinct but overlapping patterns across the genome. H3K9 methylation in the small, heterochromatic fourth chromosome of D. melanogaster is governed mainly by dSETDB1, whereas dSETDB1 and SU(VAR)3-9 function in concert to methylate H3K9 in the pericentric heterochromatin of all chromosomes, with dG9a having little impact in these domains, as shown by monitoring position effect variegation. To understand how these distinct heterochromatin compartments may be differentiated, we examined the developmental timing of dSETDB1 function using a knockdown strategy. dSETDB1 acts to maintain heterochromatin during metamorphosis, at a later stage in development than the reported action of SU(VAR)3-9. Surprisingly, depletion of both of these enzymes has less deleterious effect than depletion of one. These results imply that dSETDB1 acts as a heterochromatin maintenance factor that may be required for the persistence of earlier developmental events normally governed by SU(VAR)3-9. In addition, the genetic interactions between dSETDB1 and Su(var)3-9 mutations emphasize the importance of maintaining the activities of these histone methyltransferases in balance for normal genome function.
Suppression of the Double-Strand-Break-Repair Defect of the Saccharomyces cerevisiae rad57 Mutant
Authors: Fung Cindy W , Mozlin Amy M , Symington Lorraine S 
Published: February 2009

Abstract
The Rad51 paralogs Rad55 and Rad57 form a heterodimer required to mediate the formation and/or stabilization of the Rad51 filament. To further characterize the function of Rad55-Rad57, we used a combination of rad57 partial suppressors to determine whether the DNA repair and recombination defects of the rad57 mutant could be completely suppressed. The combination of all suppressors, elevated temperature, srs2, rad51-I345T, and mating-type (MAT) heterozygosity resulted in almost complete suppression of the rad57 mutant defect in the recruitment of Rad51 to DNA-damaged sites, as well as survival in response to ionizing radiation and camptothecin. In a physical assay to monitor the kinetics of double-strand-break (DSB)-induced gene conversion, the rad57 mutant defect was effectively suppressed by srs2 and MAT heterozygosity, but these same suppressors failed to suppress the spontaneous recombination defect. Thus the Rad55-Rad57 heterodimer appears to have a unique function in spontaneous recombination that is not essential for DSB repair. Furthermore, we investigated the currently unknown mechanism of rad57 suppression by MAT heterozygosity and found that it is independent of DNL4.
Responding to Compliance Changes in a Lung Model During Manual Ventilation: Perhaps Volume, Rather Than Pressure, Should be Displayed
Authors: Kattwinkel John , Stewart Corrine , Walsh Brian , Gurka Matthew , Paget-Brown Alix 
Published: February 2009

Objective. The standard technique for positive-pressure ventilation is to regulate the breath size by varying the pressure applied to the bag. Investigators have argued that consistency of peak inspiratory pressure is important. However, research shows that excessive tidal volume delivered with excessive pressure injures preterm lungs, which suggests that inspiratory pressure should be varied during times of changing compliance, such as resuscitation of newborns or treatment after surfactant delivery.
Methods. We modified a computerized lung model (ASL5000 [IngMar Medical, Pittsburgh, PA]) to simulate the functional residual capacity of a 3-kg neonate with apnea and programmed it to change compliance during ventilation. Forty-five professionals were blinded to randomized compliance changes while using a flow-inflating bag, a self-inflating bag, and a T-piece resuscitator. We instructed subjects to maintain a constant inflation volume, first while blinded to delivered volume and then with volume displayed, with all 3 devices.
Results. Subjects adapted to compliance changes by adjusting inflation pressure more effectively when delivered volume was displayed. When only pressure was displayed, sensing of compliance changes occurred only with the self-inflating bag. When volume was displayed, adjustments to compliance changes occurred with all 3 devices, although the self-inflating bag was superior.
Conclusions. In this lung model, volume display permitted far better detection of compliance changes compared with display of only pressure. Devices for administration of positive-pressure ventilation should display volume rather than pressure.
Food Protein-Induced Enterocolitis Syndrome: 16-Year Experience
Authors: Mehr Sam , Kakakios Alyson , Frith Katie , Kemp Andrew S. 
Published: February 2009

Objective. The goal was to examine the demographic characteristics, causative foods, clinical features, treatments, and outcomes for children presenting with acute food protein-induced enterocolitis syndrome.
Methods. This was a retrospective study of children with food protein-induced enterocolitis syndrome who presented to the Children's Hospital at Westmead (Sydney, Australia) over 16 years.
Results. Thirty-five children experienced 66 episodes of food protein-induced enterocolitis syndrome. The mean age at initial presentation was 5.5 months. Children frequently experienced multiple episodes before a correct diagnosis was made. Twenty-nine children reacted to 1 food, and 6 reacted to 2 foods. Causative foods for the 35 children were rice (n = 14), soy (n = 12), cow's milk (n = 7), vegetables and fruits (n = 3), meats (n = 2), oats (n = 2), and fish (n = 1). In the 66 episodes, vomiting was the most common clinical feature (100%), followed by lethargy (85%), pallor (67%), and diarrhea (24%). A temperature of &lt;36°C at presentation was recorded for 24% of episodes. A platelet count of &gt;500 × 109 cells per L was recorded for 63% of episodes with blood count results. Only 2 of the 19 children who presented to an emergency department with their initial reactions were discharged with correct diagnoses. Additional investigations of food protein-induced enterocolitis syndrome episodes presenting to the hospital were common, with 34% of patients undergoing abdominal imaging, 28% undergoing a septic evaluation, and 22% having a surgical consultation. Prognosis was good, with high rates of resolution for the 2 most common food triggers (ie, rice and soy) by 3 years of age.
Conclusions. Misdiagnosis and delays in diagnosis for children with food protein-induced enterocolitis syndrome were common, leading many children to undergo unnecessary, often painful investigations. Decreased body temperature and thrombocytosis emerge as additional features of the syndrome.
Protective Effect of Perindopril on Diabetic Retinopathy Is Associated With Decreased Vascular Endothelial Growth Factor–to–Pigment Epithelium–Derived Factor Ratio
Authors: Zheng Zhi , Chen Haibing , Ke Genjie , Fan Ying , Zou Haidong , Sun Xiaodong , Gu Qing , Xu Xun , Ho Patrick C.P. 
Published: February 2009

OBJECTIVE
This study aimed to verify whether the decreased vascular endothelial growth factor (VEGF)–to–pigment epithelium–derived factor (PEDF) ratio can serve as an indicator for the protective effect of angiotensin-converting enzyme inhibitors (ACEIs) on diabetic retinopathy (DR) and to investigate the role of mitochondrial reactive oxygen species (ROS) in the downregulated VEGF-to-PEDF ratio.

RESEARCH DESIGN AND METHODS
Diabetic rats and control animals were randomly assigned to receive perindopril or vehicle for 24 weeks, and bovine retinal capillary endothelial cells (BRECs) were incubated with normal or high glucose with or without perindopril. VEGF, PEDF, PPARγ, and uncoupling protein-2 (UCP-2) in the rat retinas or BREC extracts were examined by Western blotting and real-time RT-PCR. The levels of VEGF and PEDF in cell culture media were examined by ELISA. Mitochondrial membrane potential (Δψm) and ROS production were assayed using JC-1 or CM-H2DCFDA.

RESULTS
The VEGF-to-PEDF ratio was increased in the retina of diabetic rats; perindopril lowered the increased VEGF-to-PEDF ratio in diabetic rats and ameliorated the retinal damage. In BRECs, perindopril lowered the hyperglycemia-induced elevation of VEGF-to-PEDF ratio by reducing mitochondrial ROS. We found the decreased ROS production was a result of perindopril-induced upregulation of PPARγ and UCP-2 expression and the subsequent decrease of Δψm.

CONCLUSIONS
It is concluded that the protective effect of ACEI on DR is associated with a decreased VEGF-to-PEDF ratio, which involves the mitochondria-ROS pathway through PPARγ-mediated changes of UCP-2. This study paves a way for future application of ACEI in treatment of DR.
Functional Targets of the Monogenic Diabetes Transcription Factors HNF-1α and HNF-4α Are Highly Conserved Between Mice and Humans
Authors: Boj Sylvia F. , Servitja Joan Marc , Martin David , Rios Martin , Talianidis Iannis , Guigo Roderic , Ferrer Jorge 
Published: February 2009

OBJECTIVE
The evolutionary conservation of transcriptional mechanisms has been widely exploited to understand human biology and disease. Recent findings, however, unexpectedly showed that the transcriptional regulators hepatocyte nuclear factor (HNF)-1α and -4α rarely bind to the same genes in mice and humans, leading to the proposal that tissue-specific transcriptional regulation has undergone extensive divergence in the two species. Such observations have major implications for the use of mouse models to understand HNF-1α– and HNF-4α–deficient diabetes. However, the significance of studies that assess binding without considering regulatory function is poorly understood.

RESEARCH DESIGN AND METHODS
We compared previously reported mouse and human HNF-1α and HNF-4α binding studies with independent binding experiments. We also integrated binding studies with mouse and human loss-of-function gene expression datasets.

RESULTS
First, we confirmed the existence of species-specific HNF-1α and -4α binding, yet observed incomplete detection of binding in the different datasets, causing an underestimation of binding conservation. Second, only a minor fraction of HNF-1α– and HNF-4α–bound genes were downregulated in the absence of these regulators. This subset of functional targets did not show evidence for evolutionary divergence of binding or binding sequence motifs. Finally, we observed differences between conserved and species-specific binding properties. For example, conserved binding was more frequently located near transcriptional start sites and was more likely to involve multiple binding events in the same gene.

CONCLUSIONS
Despite evolutionary changes in binding, essential direct transcriptional functions of HNF-1α and -4α are largely conserved between mice and humans.
High Glucose Suppresses Epidermal Growth Factor Receptor/Phosphatidylinositol 3-Kinase/Akt Signaling Pathway and Attenuates Corneal Epithelial Wound Healing
Authors: Xu Ke-Ping , Li Yanfeng , Ljubimov Alexander V. , Yu Fu-Shin X. 
Published: February 2009

OBJECTIVEPatients with diabetes are at an increased risk for developing corneal complications and delayed wound healing. This study investigated the effects of high glucose on epidermal growth factor receptor (EGFR) signaling and on epithelial wound healing in the cornea.RESEARCH DESIGN AND METHODSEffects of high glucose on wound healing and on EGFR signaling were investigated in cultured porcine corneas, human corneal epithelial cells, and human corneas using Western blotting and immunofluorescence. Effects of high glucose on reactive oxygen species (ROS) and glutathione levels and on EGFR pathways were assessed in porcine and primary human corneal epithelial cells, respectively. The effects of EGFR ligands and antioxidants on high glucose–delayed epithelial wound healing were assessed in cultured porcine corneas.RESULTSHigh glucose impaired ex vivo epithelial wound healing and disturbed cell responses and EGFR signaling to wounding. High glucose suppressed Akt phosphorylation in an ROS-sensitive manner and decreased intracellular glutathione in cultured porcine corneas. Exposure to high glucose for 24 h resulted in an increase in ROS-positive cells in primary human corneal epithelial cells. Whereas heparin-binding EGF-like growth factor and antioxidant N-acetylcysteine had beneficial effects on epithelial wound closure, their combination significantly accelerated high glucose–delayed wound healing to a level similar to that seen in control subjects. Finally, Akt signaling pathway was perturbed in the epithelia of human diabetic corneas, but not in the corneas of nondiabetic, age-matched donors.CONCLUSIONSHigh glucose, likely through ROS, impairs the EGFR–phosphatidylinositol 3-kinase/Akt pathway, resulting in delayed corneal epithelial wound healing. Antioxidants in combination with EGFR ligands may be promising potential therapeutics for diabetic keratopathy.