bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diels–Alder Reactions of Symmetrically 1,4‐Disubstituted Dienes: Theoretical Study on the Influence of the Configuration of the Double Bonds on the Regio‐ and Endoselectivity
Authors: Baki Samira , Maddaluno Jacques , Derdour Aïcha , Chaquin Patrick 
Published: April 2008

AbstractIt was experimentally shown in Diels‐Alder reactions that symmetrically 1,4‐disubstituted dienes exhibit high regio‐ and endoselectivity induced by the (E,Z) configuration of the double bonds. In order to understand the origin of this selectivity, the transition states associated with the reaction between a series of such dienes (R = OMe, CH3, NH2, F, CN) on substituted ethylene (R′ = CO2Me, CN, F, OMe) were determined by DFT calculations. If the regioselectivity confirmed by a single‐point MP2 calculation is predicted to be good in most cases, its direction remains difficult to predict; the R′ group of the dienophile can orient itself toward either the (Z) or the (E) side of the diene. Neither primary nor secondary frontier orbital interactions appear to be able to rationalize these results. They are more likely explained by a delicate balance between steric and electrostatic interactions. This hypothesis is further supported by the calculated reactivity of the (E,E) and (Z,Z) corresponding dienes. In any case, a standard DFT calculation, confirmed by a single‐point MP2 step, is likely to provide a reliable guideline for a synthesis strategy that allows the control of up to four stereogenic centres in a single reaction step.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Do Ramadan fasting restrictions alter eating behaviours?
Authors: Erol Atila , Baylan Gonul , Yazici Fadime 
Published: April 2008

AbstractDuring Ramadan month, Muslims should refrain from drinking, eating and smoking from dawn to sunset. Ramadan fasting can be considered as a kind of dietary restriction. Eating restriction is a risk factor for later development of eating disorders. The purpose of this study is to evaluate whether Ramadan fasting changes the eating behaviours of young people, especially girls who are known as the most vulnerable group for eating disorders. Our sample consisted of 79 healthy volunteers from a high school (63 females; mean age = 16.29; 16 males; mean age = 16.31) who fasted during the Ramadan month. No statistically significant differences were found between the scores of EAT (Eating Attitude Test) and BITE (Bulimic Investigatory Test, Edinburgh) which were administered within the weeks before and after Ramadan. According to our results Ramadan fasting restrictions do not seem to change the eating behaviours of young girls and boys. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.
Application of local DFD method to simulate unsteady flows around an oscillating circular cylinder
Authors: Wu Y. L. , Shu C. 
Published: April 2008

AbstractIn this paper, the recently proposed local domain‐free discretization (DFD) method is applied to simulate incompressible flows around an oscillating circular cylinder. It is found that it is very easy for the local DFD method to handle such moving boundary flow problems. This is because it does not need to move the mesh, which is indeed needed in traditional methods. Numerical experiments show that the present numerical results agree very well with the available data in the literature, and that the local DFD method is an effective tool for the computation of moving boundary flow problems. Copyright © 2008 John Wiley & Sons, Ltd.
Assessing departure from Hardy‐Weinberg equilibrium in the presence of disease association
Authors: Li Mingyao , Li Chun 
Published: April 2008

AbstractAssessing Hardy‐Weinberg equilibrium (HWE) is often employed as an important initial step for genotype data quality checking in genetics studies. Tests for HWE often assume that the genotypes are randomly sampled from the general population. However, in many human genetics studies, subjects are ascertained through their disease status, and affected individuals (and their relatives in family‐based studies) are overly represented in the ascertained sample than in the general population. As a result, when a marker is associated with the disease, the type I error rate in the HWE tests can be inflated, leading to false exclusion of associated markers from future analysis. Here we develop a general likelihood framework that allows assessment of departure from HWE while taking into account potential association with the disease. Our method can differentiate HWE departure caused by disease association from departure caused by other reasons, such as genotyping errors. The framework can be used for various data structures, including unrelated cases and controls, nuclear families with one or more offspring, or a mixture of them. The type I error rate of our test is under control for a broad range of scenarios. For case‐control data, compared to the traditional HWE test that uses only controls, our test is more powerful to detect HWE departure for common diseases and has comparable power for rare diseases. For case‐parents trios, our test is more powerful than the traditional HWE test that uses parents only. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
A novel method to establish microglia‐free astrocyte cultures: Comparison of matrix metalloproteinase expression profiles in pure cultures of astrocytes and microglia
Authors: Crocker Stephen J. , Frausto Ricardo F. , Whitton J. Lindsay , Milner Richard 
Published: April 2008

AbstractIncreased matrix metalloproteinase (MMP) proteolytic activity contributes to the pathogenesis of many neuroinflammatory and neurodegenerative conditions in the CNS. To fully understand this process, it is important to define the MMP expression profile of specific cell types, including the CNS‐resident cells astrocytes and microglia. While previous studies have characterized astrocyte MMP expression by using mixed glial cultures, these results are likely complicated by the presence of contaminating microglia within these cultures. In the current study, we sought to clarify this complexity, by taking a novel approach to prepare pure astrocyte cultures entirely devoid of microglia, by promoting neural stem cell (NSC) differentiation into astrocytes. The MMP expression profile of mixed glial cultures, neurosphere‐derived astrocytes, and pure microglia was characterized by RNase protection assay. This revealed that MMP gene expression is largely cell‐type specific. Astrocytes constitutively expressed MMP‐11, MMP‐14, and MMP‐2 and showed induction of MMP‐3 in response to IL‐1β but did not respond to lipopolysaccharide (LPS). In contrast, microglia constitutively expressed high levels of MMP‐12 and showed strong induction of MMP‐9 and MMP‐14 in response to LPS. Gelatin zymography confirmed that LPS and TNF‐α induced strong expression of MMP‐9 in microglia but not astrocytes. In summary, these studies demonstrate that neurosphere‐derived astrocytes represent an attractive alternative system in which to study astrocyte behavior in vitro. Using this system, we have shown that astrocytes and microglia express distinct sets of MMP genes and that microglia, not astrocytes, are the major source of MMP‐9 in response to LPS or TNF‐α. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration biopsy versus ultrasound‐guided fine‐needle aspiration biopsy: Cost‐effectiveness as a frontline diagnostic modality for solitary thyroid nodules
Authors: Khalid Ayesha N. , Quraishi Sadeq A. , Hollenbeak Christopher S. , Stack Brendan C. 
Published: April 2008

AbstractBackgroundUltrasound‐guided fine‐needle aspiration biopsy (ultrasound‐guided FNAB) is considered the diagnostic test of choice when a fine‐needle aspiration biopsy (FNAB) returns an inconclusive diagnosis because of cytologic ambiguity or paucity of specimen.MethodsCost‐effectiveness analysis utilizing a decision tree was used to model the diagnostic strategies. The decision analysis model was parameterized using costs from a large, academic medical center and probabilities from existing literature. Outcomes included the incremental cost per additional case correctly diagnosed.ResultsAll data are reported as frontline ultrasound‐guided FNAB strategy versus FNAB strategy—expected cost: $1329 versus $1312; expected number of cases correctly diagnosed (per 1000 biopsies): 980 versus 920; incremental cost per additional correctly diagnosed case: $289.ConclusionThe use of ultrasound‐guided FNAB as the initial modality for tissue biopsy of a thyroid nodule is more effective than traditional FNAB at an additional cost of $289 per additional correct diagnosis. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Chemical and isotopic assessment in volcanic thermal waters: Cases of Ischia (Italy) and São Miguel (Azores, Portugal)
Authors: Morell Ignacio , Pulido‐Bosch Antonio , Daniele Linda , Cruz José Virgilio 
Published: April 2008

AbstractIsotopic fractionation of 10B/11B provides a sound tool for identifying hydrogeochemical processes in complex areas, owing to its ability to discriminate between various scenarios. In addition, the occurrence of boron as a minor element in areas of active volcanism allows its use in comparison with concentrations of other conservative or non‐conservative ions. This allows the detection of water mixtures of diverse origin and temperature, deep or shallow, including fresh water, seawater and even brines. This tool was applied in studies of the volcanic islands of Ischia and São Miguel, across widely differing geographical and climatic contexts. Five groups of waters have been identified in Ischia Island: marine, transition, hot carbonated, cold carbonated and fresh waters. For São Miguel Island the identified groups are cold carbonic, hot carbonic, boiling and acidic boiling waters. Copyright © 2008 John Wiley & Sons, Ltd.
Tumoricidal activity of high‐dose tumor necrosis factor‐α is mediated by macrophage‐derived nitric oxide burst and permanent blood flow shutdown
Authors: Menon Chandrakala , Bauer Todd W. , Kelley Scott T. , Raz Dan J. , Bleier Joshua I. , Patel Krina , Steele Kirsten , Prabakaran Indira , Shifrin Alexander , Buerk Donald G. , Sehgal Chandra M. , Fraker Douglas L. 
Published: April 2008

AbstractThis study investigates the role of tumor nitric oxide (NO) and vascular regulation in tumor ulceration following high‐dose tumor necrosis factor‐α (TNF) treatment. Using TNF‐responsive (MethA) and nonresponsive (LL2) mouse tumors, tumor NO concentration was measured with an electrochemical sensor and tumor blood flow by Doppler ultrasound. Mice were also pretreated with a selective inducible nitric oxide synthase (iNOS) inhibitor, 1400 W. Tumors harvested from TNF‐treated mice were cryosectioned and immunostained for murine macrophages, or/and iNOS. MethA tumor‐bearing mice were depleted of macrophages. Pre‐ and post‐TNF tumor NO levels were measured continuously, and mice were followed for gross tumor response. In MethA tumors, TNF caused a 96% response rate, and tumor NO concentration doubled. Tumor blood flow decreased to 3% of baseline by 4 hr and was sustained at 24 hr and 10 days post‐TNF. Selective NO inhibition with 1400 W blocked NO rise and decreased response rate to 38%. MethA tumors showed tumor infiltration by macrophages post‐TNF and the pattern of macrophage immunostaining overlapped with iNOS immunostaining. Depletion of macrophages inhibited tumor NO increase and response to TNF. LL2 tumors had a 0% response rate to TNF and exhibited no change in NO concentration. Blood flow decreased to 2% of baseline by 4 hr, recovered to 56% by 24 hr and increased to 232% by 10 days. LL2 tumors showed no infiltration by macrophages post‐TNF. We conclude that TNF causes tumor infiltrating, macrophage‐derived iNOS‐mediated tumor NO rise and sustained tumor blood flow shutdown, resulting in tumor ulceration in the responsive tumor. © 2008 Wiley‐Liss, Inc.
Body size and risk of epithelial ovarian and related cancers: A population‐based case‐control study
Authors: Olsen Catherine M. , Nagle Christina M. , Whiteman David C. , Purdie David M. , Green Adèle C. , Webb Penelope M. 
Published: April 2008

AbstractDifferent subtypes of ovarian cancer appear to have different causes; however, the association between body mass index (BMI) and the different subtypes is unclear. We examined the associations between body‐mass index (BMI) and weight gain and risk of the different histological subtypes of epithelial ovarian cancer in a case‐control study in Australia. Cases aged 18–79 with a new diagnosis of invasive epithelial ovarian cancer (n = 1,269) or borderline tumor (n = 311) were identified through a network of clinics and cancer registries throughout Australia. Controls (n = 1,509) were selected from the Electoral Roll. Height and weight (1 year previously, at age 20 and maximum weight) and other risk factor information were ascertained via a self‐administered questionnaire. Obesity was positively associated with clear cell tumors (Odds Ratio 2.3; 95% confidence interval 1.2–4.2) but not invasive endometrioid or mucinous tumors. Although there was no association with invasive serous tumors overall (0.9; 0.7–1.2), we did see an increased risk of serous peritoneal tumors (2.9; 1.7–4.9), but not of serous tumors of the ovary and fallopian tube. Of the borderline subtypes, obesity was positively associated with serous (1.8; 1.1–2.8) but not mucinous tumors (1.1; 0.7–1.7). Overweight was not associated with any subtype overall. There was no association with BMI at age 20, or weight gain for any of the histological subtypes. These results add to the current evidence that obesity increases a woman's risk of developing distinct histological subtypes of ovarian cancer. © 2008 Wiley‐Liss, Inc.
Variants in DNA double‐strand break repair and DNA damage‐response genes and susceptibility to lung and head and neck cancers
Authors: Danoy Patrick , Michiels Stefan , Dessen Philippe , Pignat Cécile , Boulet Thomas , Monet Marion , Bouchardy Christine , Lathrop Mark , Sarasin Alain , Benhamou Simone 
Published: April 2008

AbstractCigarette smoking is the major risk factor for lung cancer, and together with alcohol for head and neck (HN) cancer. These genotoxics produced DNA damage and particularly double‐strand breaks (DSB) that are removed by various repair pathways. To understand the initiation of these cancers, we performed a genotype analysis to correlate some variants in specific genes in a case‐control study of lung and HN cancers. In a discovery phase, we sequenced DNA samples of 32 healthy Caucasians to describe genetic variants in 30 genes involved in the repair of DSB and in DNA damage response. 625 variants were detected on 29 out of the 30 genes successfully screened by sequencing exons, parts of introns and flanking regions. These included 470 non‐exonic variants, from which 33 insertions/deletions, and 155 exonic alterations, corresponding to 59 non synonymous polymorphisms. 223 of these variants were not previously described. In total, 379 variants were successfully genotyped in a case‐control study restricted to smokers including 151 lung cases, 251 HN cases, and 172 controls. To account for multiple testing, we associated to each p‐value a proportion of false positives (q‐value). Haplotype‐analysis suggested potential associations (p < 0.05) between lung cancer and 2 genes (RECQL4 and RAD52), which came with q‐value of 8%, and between HN cancer and 1 gene (DNA‐PK) but with q‐value of 56%. The 3 genes are key players for regulating the efficiency of DSB repair. Large‐scale studies are needed to show if any of these 3 variants are truly associated with an increased risk of cancer. © 2008 Wiley‐Liss, Inc.
Effect of surface roughness, porosity, and a resorbable calcium phosphate coating on osseointegration of titanium in a minipig model
Authors: Schwarz Markus L. R. , Kowarsch Markus , Rose Steffen , Becker Kristianna , Lenz Tamara , Jani Lutz 
Published: April 2008

AbstractThe aim of this study was to compare the osseointegration of four different implant surfaces in the Göttingen minipig femur model. They were prepared by glasspearlblasting (A), sandblasting (B) and titaniumplasma spraying (C and D). Surface D received additionally an electrochemically deposited layer of a resorbable calcium phosphate (CaP) layer, made mainly of brushite. Sample size was n = 20 per group. Implants were placed in the intertrochanteric and intercondylar sites of both femora. After 12 weeks, implant anchorage was measured by the pull‐out test and histomorphometry measurements were carried out at the bone‐implant interface. Implant anchorage was 0.7 ± 0.3 MPa for surface A, 3.2 ± 0.6 MPa for surface B, 6.5 ± 1.5 MPa for surface C and 7.3 ± 1.9 MPa for surface D. The differences between surfaces were statistically significant, with exception of C and D. The stiffness of the bone‐implant interface showed no statistically significant difference between surfaces. After pull‐out, surface A and B showed nearly no bone spots, while on surfaces C and D bone remains were found. Bone‐implant contact was 1.9 ± 1.1% for surface A, 10.5 ± 3.6% for surface B, 22.4 ± 4.5% for surface C and 48.8 ± 4.5% for surface D. The differences were statistically significant. Implant location, intertrochanteric and intercondylar, did not affect the data. In this minipig model, rougher surfaces showed better osseointegration. After 12 weeks of healing, the resorbable CaP layer enhanced significantly the bone‐implant contact but not the level of anchorage. The findings also suggest that the pull‐out test should be critically evaluated to determine the shear strength between bone and porous surfaces. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Microfabricated multilayer parylene‐C stencils for the generation of patterned dynamic co‐cultures
Authors: Jinno Satoshi , Moeller Hannes‐Christian , Chen Chia‐Ling , Rajalingam Bimal , Chung Bong Geun , Dokmeci Mehmet R. , Khademhosseini Ali 
Published: April 2008

AbstractCo‐culturing different cell types can be useful to engineer a more in vivo‐like microenvironment for cells in culture. Recent approaches to generating cellular co‐cultures have used microfabrication technologies to regulate the degree of cell–cell contact between different cell types. However, these approaches are often limited to the co‐culture of only two cell types in static cultures. The dynamic aspect of cell–cell interaction, however, is a key regulator of many biological processes such as early development, stem cell differentiation, and tissue regeneration. In this study, we describe a micropatterning technique based on microfabricated multilayer parylene‐C stencils and demonstrate the potential of parylene‐C technology for co‐patterning of proteins and cells with the ability to generate a series of at least five temporally controlled patterned co‐cultures. We generated dynamic co‐cultures of murine embryonic stem cells in culture with various secondary cell types that could be sequentially introduced and removed from the co‐cultures. Our studies suggested that dynamic co‐cultures generated by using parylene‐C stencils may be applicable in studies investigating cellular interactions in controlled microenvironments such as studies of ES cell differentiation, wound healing and development. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Growth factors reduce the suppression of proliferation and osteogenic differentiation by titanium particles on MSCs
Authors: Jeong Woong‐Kyo , Park Sang‐Won , Im Gun‐Il 
Published: April 2008

AbstractThis study was conducted to test the hypothesis that growth factors can reduce the suppressive effect of titanium particles on MSCs. Cultured human MSCs at passage 3 were challenged with prepared cpTi particles at a concentration of 500 particles/cell along with one of the following growth factors: TGF‐β1 (10 ng/mL), FGF‐2 (10 ng/mL), IGF‐I (100 ng/mL), and BMP‐6 (50 ng/mL). After various periods of time, the treatment effects on cellular proliferation, viability, and osteogenic differentiation were measured. All the four growth factors positively promoted cell proliferation and viability to a varying extent. FGF‐2 most effectively enhanced cell proliferation, whereas IGF‐I was the most effective growth factor for enhancing cell viability. FGF‐2, IGF‐I, and BMP‐6 reversed the titanium‐mediated suppression of osteogenic differentiation, BMP‐6 being the most effective one. Various growth factors can mitigate the suppressive effects of titanium particles on MSCs and enhance cell proliferation, viability, and osteogenic differentiation. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Convergence of electric field and electric field gradient versus atomic basis sets in all‐siliceous and Mg substituted phillipsites
Authors: Larin A. V. , Sakodynskaya I. K. , Trubnikov D. N. 
Published: April 2008

AbstractElectrostatic potential (EP), electric field (EF), and electric field gradient (EFG) values are calculated in periodic models of magnesium substituted phillipsite (MgPHI) zeolite forms using periodic DFT (PDFT) hybrid B3LYP level with fourteen different basis sets. Relative root mean square differences between the EP, EF, or EFG values estimated between different basis sets are evaluated in several spatial domains available for adsorbate molecules in the zeolite. In these areas, the EF increase in MgPHI is evaluated relative to all‐siliceous PHI types. The EP is interpreted in terms of framework ionicity for MgPHI and all‐siliceous PHI models. Angular SiOSi dependence of the EFG asymmetry at17O atoms in all‐siliceous zeolites is discussed. © 2008 Wiley Periodicals, Inc. J Comput Chem 2008
Depressive symptoms and bias in perceived social competence among young adults
Authors: Whitton Sarah W. , Larson Justine J. , Hauser Stuart T. 
Published: April 2008

AbstractWe examined associations between depressive symptoms and young adults' self‐perceptions of social competence to explore whether higher symptoms are associated with self‐evaluations that are more accurate (i.e., depressive realism), negatively biased (i.e., cognitive distortion), or less accurate (i.e., self‐verification perspective). In 133 young adults, depressive symptoms and discrepancies between self‐ and peer ratings of social competence were assessed. Results demonstrated a linear relationship between depressive symptoms and self‐peer discrepancies, such that higher symptoms were associated with underestimation of the self and low symptom levels were linked with overestimation of the self relative to peer evaluations. These findings suggest negative bias in dysphorics' self‐perceptions, supporting cognitive distortion models, as well as positive bias in self‐perceptions of those with low depressive symptoms. © 2008 Wiley Periodicals, Inc. J Clin Psychol 64: 1–15, 2008.
Interchromatidal central ridge and transversal symmetry in early metaphasic human chromosome one
Authors: Argüello‐Miranda Orlando , Sáenz‐Arce Giovanni 
Published: April 2008

AbstractThe topographic structure of Giemsa‐banded (G‐banded) early metaphase human chromosomes adsorbed on glass was analyzed by atomic force microscope using amplitude modulation mode (AM‐AFM). Longitudinal height measurements for early metaphasic human chromosomes showed a central ridge that was further characterized by transversal height measurements. The heterochromatic regions displayed a high level of transversal symmetry, while the euchromatic ones presented several peaks across the transversal height measurements. We suggest that this central ridge and symmetry patterns point out a transitional arrangement of the early metaphase chromosome and support evidence for interchromatidal interactions prior to disjunction. Copyright © 2008 John Wiley & Sons, Ltd.