bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk management with options and futures under liquidity risk
Authors: Adam‐Müller Axel F. A. , Panaretou Argyro 
Published: January 2009

AbstractFutures hedging creates liquidity risk through marking to market. Liquidity risk matters if interim losses on a futures position have to be financed at a markup over the risk‐free rate. This study analyzes the optimal risk management and production decisions of a firm facing joint price and liquidity risk. It provides a rationale for the use of options on futures in imperfect capital markets. If liquidity risk materializes, the firm sells options on futures in order to partly cover this liquidity need. It is shown that liquidity risk reduces the optimal hedge ratio and that options are not normally used before a liquidity need actually arises. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 29:297–318, 2009
Asymptotic tests of association with multiple SNPs in linkage disequilibrium
Authors: Pan Wei 
Published: January 2009

AbstractWe consider detecting associations between a trait and multiple single nucleotide polymorphisms (SNPs) in linkage disequilibrium (LD). To maximize the use of information contained in multiple SNPs while minimizing the cost of large degrees of freedom (DF) in testing multiple parameters, we first theoretically explore the sum test derived under a working assumption of a common association strength between the trait and each SNP, testing on the corresponding parameter with only one DF. Under the scenarios that the association strengths between the trait and the SNPs are close to each other (and in the same direction), as considered by Wang and Elston [Am. J. Hum. Genet. [2007] 80:353–360], we show with simulated data that the sum test was powerful as compared to several existing tests; otherwise, the sum test might have much reduced power. To overcome the limitation of the sum test, based on our theoretical analysis of the sum test, we propose five new tests that are closely related to each other and are shown to consistently perform similarly well across a wide range of scenarios. We point out the close connection of the proposed tests to the Goeman test. Furthermore, we derive the asymptotic distributions of the proposed tests so that P‐values can be easily calculated, in contrast to the use of computationally demanding permutations or simulations for the Goeman test. A distinguishing feature of the five new tests is their use of a diagonal working covariance matrix, rather than a full covariance matrix as used in the usual Wald or score test. We recommend the routine use of two of the new tests, along with several other tests, to detect disease associations with multiple linked SNPs. Genet. Epidemiol. 33:497–507, 2009. © 2009 Wiley‐Liss, Inc.
Endothelial NOS‐deficient mice reveal dual roles for nitric oxide during experimental autoimmune encephalomyelitis
Authors: Wu Muzhou , Tsirka Stella E. 
Published: January 2009

AbstractMultiple sclerosis (MS) is a demyelinating autoimmune disease characterized by infiltration of T cells into the central nervous system (CNS) after compromise of the blood‐brain barrier. A model used to mimic the disease in mice is experimental autoimmune encephalomyelitis (EAE). In this report, we examine the clinical and histopathological course of EAE in eNOS‐deficient (eNOS−/−) mice to determine the role of nitric oxide (NO) derived from this enzyme in the disease progression. We find that eNOS−/− mice exhibit a delayed onset of EAE that correlates with delayed BBB breakdown, thus suggesting that NO production by eNOS underlies the T cell infiltration into the CNS. However, the eNOS−/− mice also eventually exhibit more severe EAE and delayed recovery, indicating that NO undertakes dual roles in MS/EAE, one proinflammatory that triggers disease onset, and the other neuroprotective that promotes recovery from disease exacerbation events. © 2009 Wiley‐Liss, Inc.
Mechanical control of cAMP signaling through integrins is mediated by the heterotrimeric Gαs protein
Authors: Alenghat Francis J. , Tytell Jessica D. , Thodeti Charles K. , Derrien Alexandrine , Ingber Donald E. 
Published: January 2009

AbstractMechanical stresses that are preferentially transmitted across the cell surface via transmembrane integrin receptors activate gene transcription by triggering production of intracellular chemical second messengers, such as cAMP. Here we show that the sensitivity of the cAMP signaling pathway to mechanical stresses transferred across β1 integrins is mediated by force‐dependent activation of the heterotrimeric G protein subunit Gαs within focal adhesions at the site of stress application. Gαs is recruited to focal adhesions that form within minutes following clustering of β1 integrins induced by cell binding to magnetic microbeads coated with activating integrin ligands, and β1 integrin and Gαs co‐precipitate when analyzed biochemically. Stress application to activated β1 integrins using magnetic twisting cytometry increases Gαs recruitment and activates these large G proteins within focal adhesions, as measured by binding of biotinylated azido‐anilido‐GTP, whereas application of similar stresses to inactivated integrins or control histocompatibility antigens has little effect. This response is relevant physiologically as application of mechanical strain to cells bound to flexible extracellular matrix‐coated substrates induce translocation of phospho‐CREB to the nucleus, which can be attenuated by inhibiting Gαs activity, either using the inhibitor melittin or suppressing its expression using siRNA. Although integrins are not typical G protein‐coupled receptors, these results show that integrins focus mechanical stresses locally on heterotrimeric G proteins within focal adhesions at the site of force application, and transduce mechanical stimuli into an intracellular cAMP signaling response by activating Gαs at these membrane signaling sites. J. Cell. Biochem. 106: 529–538, 2009. © 2009 Wiley‐Liss, Inc.
FGF8 regulates myogenesis and induces Runx2 expression and osteoblast differentiation in cultured cells
Authors: Omoteyama Kazuki , Takagi Minoru 
Published: January 2009

AbstractIn the current study, treatment of the rat osteogenic cell line ROB‐C26 cells with fibroblast growth factor 8 (FGF8) stimulated alkaline phosphatase (ALP) activity, and also induced the expression of the Runx2 transcription factor, and increased the activity of a luciferase reporter gene containing the osteocalcin (OCN) promoter and six copies of the osteoblast specific cis‐acting element 2 (OSE2) response element. In contrast, FGF8 treatment of the mouse myoblast cell line C2C12 inhibited the expression of desmin and the synthesis of myotubes. The expression of MyoD, Myogenin, Foxc2, and Hand1 was also decreased by FGF8. Transient expression of Foxc2 in C2C12 cells induced the expression of Hand1, and chromatin immunoprecipitation (ChIP) analysis indicated that Foxc2 binds to the promoter region of the Hand1 gene. These results indicated that Foxc2 is directly involved in the regulation of Hand1 expression. The results of the current study indicate that FGF8 regulates myoblast differentiation through the regulation of MyoD expression, and that this regulation is independent of Hand1 in cultured cells. Conversely, FGF8 supports bone development and cell differentiation though the induction of Runx2 expression. J. Cell. Biochem. 106: 546–552, 2009. © 2009 Wiley‐Liss, Inc.
IFI16 and NM23 bind to a common DNA fragment both in the P53 and the cMYC gene promoters
Authors: Egistelli Lorenza , Chichiarelli Silvia , Gaucci Elisa , Eufemi Margherita , Schininà M. Eugenia , Giorgi Alessandra , Lascu Ioan , Turano Carlo , Giartosio Anna , Cervoni Laura 
Published: January 2009

AbstractIn the melanoma M14 cell line, we found that the antimetastatic protein NM23/nucleoside diphosphate kinase binds to the promoters of the oncogene cMYC and of P53, a gene often mutated in human cancer (Cervoni et al. [2006] J. Cell. Biochem. 98:421–428). In a further study, we find now that IFI16, a transcriptional repressor, in both promoters binds to the G‐rich fragment that also binds NM23/NDPK. These fragments possess non‐B DNA structures. Moreover, by sequential chromatin immunoprecipitation (re‐ChIP) we show that the two proteins (IFI16 and NM23/NDPK) are simultaneously bound in vivo to the same DNA fragments. Since P53 stimulates apoptosis and inhibits cellular growth, and cMYC promotes cell growth and, in several instances, also apoptosis, the presence of NM23 and IFI16 on the same DNA fragments suggests their common involvement in the reduced development of some tumors. J. Cell. Biochem. 106: 666–672, 2009. © 2009 Wiley‐Liss, Inc.
SHARPEN—Systematic Hierarchical Algorithms for Rotamers and Proteins on an Extended Network
Authors: Loksha Ilya V. , Maiolo James R. , Hong Cheng W. , Ng Albert , Snow Christopher D. 
Published: January 2009

AbstractAlgorithms for discrete optimization of proteins play a central role in recent advances in protein structure prediction and design. We wish to improve the resources available for computational biologists to rapidly prototype such algorithms and to easily scale these algorithms to many processors. To that end, we describe the implementation and use of two new open source resources, citing potential benefits over existing software. We discuss CHOMP, a new object‐oriented library for macromolecular optimization, and SHARPEN, a framework for scaling CHOMP scripts to many computers. These tools allow users to develop new algorithms for a variety of applications including protein repacking, protein–protein docking, loop rebuilding, or homology model remediation. Particular care was taken to allow modular energy function design; protein conformations may currently be scored using either the OPLSaa molecular mechanical energy function or an all‐atom semiempirical energy function employed by Rosetta. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009
Perfusion affects the tissue developmental patterns of human mesenchymal stem cells in 3D scaffolds
Authors: Zhao Feng , Grayson Warren L. , Ma Teng , Irsigler Andre 
Published: January 2009

AbstractHuman mesenchymal stem cells (hMSCs) developed in three‐dimensional (3D) scaffolds are significantly affected by culture conditions. We hypothesized that the hydrodynamic forces generated in perfusion bioreactors significantly affected hMSC functionality in 3D scaffolds by shaping the extracellular matrix (ECM) proteins. In this study, hMSCs were grown in 3D poly(ethylene terephthalate) (PET) scaffolds in static and a parallel perfusion system under similar initial conditions for up to 35 days. Results demonstrated that even at very low media velocities (O [10−4 cm/sec]), perfusion cultures affected the ability of hMSCs to form an organized ECM network as illustrated by the immunostaining of collagen I and laminin fibrous structure. The change in the ECM microenvironment consequently influenced the nuclear shape. The hMSCs grown at the lower surface of static culture displayed a 15.2 times higher nuclear elongation than those at the upper surface, whereas cells grown in the perfusion bioreactor displayed uniform spherical nuclei on both surfaces. The difference in ECM organization and nuclear morphology associated with gene expression and differentiation characteristics of hMSCs. The cells exhibited lower CFU‐F colony forming ability and decreased expressions of stem‐cell genes of Rex‐1 and Oct‐4, implying a less primitive stem‐cell phenotype was maintained in the perfusion culture relative to the static culture conditions. The significantly higher expression level of osteonectin gene in the perfusion culture at day 28 indicated an upregulation of osteogenic ability of hMSCs. The study highlights the critical role of dynamic culture conditions on 3D hMSC construct development and properties. J. Cell. Physiol. 219: 421–429, 2009. © 2009 Wiley‐Liss, Inc.
CCCTC‐binding factor meets poly(ADP‐ribose) polymerase‐1
Authors: Caiafa Paola , Zlatanova Jordanka 
Published: January 2009

AbstractCCCTC‐binding factor (CTCF) is a ubiquitous Zn‐finger‐containing protein with numerous recognized functions, including, but not limited to, gene activation and repression, enhancer‐blocking, X‐chromosome inactivation, and gene imprinting. It is believed that the protein performs such a variety of functions by interacting with an array of very diverse proteins. In addition, CTCF undergoes several post‐translational modifications, including poly(ADP‐ribosyl)ation. The PARylated form of CTCF has recently been implicated in two important functions: gene imprinting and control of ribosomal gene transcription. Here, we summarize and critically discuss the available data on the interplay between CTCF and poly(ADP‐ribosyl)ation in these two processes. We consider the newly described phenomena in the broader context of PARP's activities, including the crucial role of protein PARylation in the regulation of the genome methylation pattern. J. Cell. Physiol. 219: 265–270, 2009. © 2009 Wiley‐Liss, Inc.
Sonographic measurement of cross‐sectional area of the median nerve in the diagnosis of carpal tunnel syndrome: Correlation with nerve conduction studies
Authors: Moran Luz , Perez Maria , Esteban Angel , Bellon Jose , Arranz Beatriz , del Cerro Miguel 
Published: January 2009

AbstractPurpose.To assess the usefulness of sonographic measurement of the median nerve cross‐sectional area (CSA) in the diagnosis of carpal tunnel syndrome (CTS) and grading of its severity using nerve conduction (NC) studies as the standard.Method.The CSA of the median nerve was measured at the tunnel inlet and outlet using the ellipse formula and automatic tracing in 72 hands with suspicion of CTS.Result.The lack of inter‐reader reliability led to excluding CSA measurements obtained at the tunnel outlet. Based on the receiver operating characteristic curves, the following cut‐off points for the CSA of the median nerve at the tunnel inlet was selected: 9.8 mm and 12.3 mm2 for the ellipse formula and 11 and 13 mm2 for automatic tracing. For the ellipse formula, a CSA less than or equal to 9.8 mm2 excluded CTS whereas a CSA greater than or equal to 12.3 mm2 was diagnostic of CTS with measurements between 9.8 and 12.3 mm2 being indeterminate and requiring NC studies. For automatic tracing, the cutoff value of 11 mm2 was excluded because of the high percentage of false negatives, whereas CSAs greater than or equal to 13 mm2 were diagnostic of CTS. There were no statistically significant differences in CSA measurements between the various degrees of CTS severity determined by NC studies.Conclusion.Sonographic measurement of median nerve CSA at the tunnel inlet is a good alternative to NC studies as the initial diagnostic test for CTS, but it cannot grade the severity of CTS as well as NC studies. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2009
LEEM investigations of surfaces using a beam of energetic self‐ions
Authors: Ondrejcek Michal , Swiech Wacek , Petrov Ivan , Rajappan Mahesh , Flynn C. Peter 
Published: January 2009

AbstractThis article reviews recent research using a low‐energy electron microscope, built by Tromp at IBM, and equipped with an accelerator that permits in situ irradiation with a beam of self‐ions. The available ion energies of 20 eV to 5 keV span the range from epitaxial growth by a hyperthermal beam to sputtering at the level of ∼10 atoms per incident ion. The design criteria and instrument calibration are described. The research described is surface science that requires a vacuum maintained below 10−10 Torr, with all components contained in the same vacuum. Two general categories of applications are sketched. Experiments that accurately measure important physical quantities include surface mass diffusion over an extended temperature range; determining the critical chemical potential at which island nucleation occurs; observation and explanation of the universal evolution by which adatom and advacancy islands both grow and shrink by beam‐driven processes; and the study of sublimation (regarded as negative ion beam intensity). Experiments described here with other goals include beam‐assisted synthesis first of large pans and mesas for isolating surface experiments (e.g., nucleation) from the surrounding crystal, and second of Fourier waves on steps, for studies of diffusive relaxation. Operation of exotic structures including Bardeen‐Herring sources and Frank growth spirals deformed by crystal anisotropy are also described. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Catastrophic payments for health care among households in urban Tamil Nadu, India
Authors: Vaishnavi Salem Deenadayalan , Dash Umakant 
Published: January 2009

AbstractUrban residents in India face important health problems due to unhygienic conditions, excessive crowding and lack of proper sanitation. The private sector has started occupying the centre stage of the health system and households are burdened with increasing levels of health expenditure. This paper aims to study out‐of‐pocket expenditure (OOPE) and the extent of catastrophic payments for health care among households in a highly urbanised state, Tamil Nadu. The study used data on morbidity and health care for the year 2004 collected by the National Sample Survey Organization, India. Care was sought for 84 per cent of illness episodes in urban areas, and the majority used private sector providers (67 per cent for inpatients and 78 per cent for outpatients). Mean OOPE for inpatients and outpatients was higher for households with higher income. The average cost burden per visit was higher among those who sought care from private providers for inpatient services (29 per cent of household consumption expenditure) and outpatient services (20% of household consumption expenditure) compared with the burden associated with public health service use (3–4 per cent of consumption expenditure). About 60 per cent of households which used private health services faced catastrophic payments at the 10 per cent threshold level. To avoid catastrophic expenditure, greater use of the public sector which is providing services at an affordable cost is needed. Improving access to public health services, better gate‐keeping systems, stronger controls on drug prices and increasing the quality of services are required to reduce the incidence of catastrophic expenditure both on inpatients and outpatients. Greater use of risk pooling mechanisms would encourage the poor to seek health care and also to protect households from all socio‐economic groups from catastrophic expenditure. Copyright © 2009 John Wiley & Sons, Ltd.
A two‐step one‐pot radiosynthesis of the potent dopamine D2/D3 agonist PET radioligand [11C]MNPA
Authors: Steiger C. , Finnema S. J. , Raus L. , Schou M. , Nakao R. , Suzuki K. , Pike V. W. , Wikström H. V. , Halldin C. 
Published: January 2009

Abstract(R)‐(−)‐2‐[11C]Methoxy‐N‐n‐propylnorapomorphine ([11C]MNPA ([11C]2)) is an agonist radioligand of interest for imaging D2/D3 receptors in vivo. Here we sought to develop an improved radiosynthesis of this radioligand. Reference 2 was synthesized in nine steps with an overall yield of about 5%, starting from codeine. Trimethylsilyldiazomethane proved to be a practical improvement in comparison to diazomethane in the penultimate methylation step. A protected precursor for radiolabeling ((R)‐(−)‐2‐hydroxy‐10,11‐acetonide‐N‐n‐propylnoraporphine, 4) was prepared from (R)‐(−)‐2‐hydroxy‐N‐n‐propylnorapomorphine (1) in 30% yield. [11C]2 was prepared from 4 via a two‐step one‐pot radiosynthesis. The first step, methylation of 4 with [11C]methyl triflate, occurred in quantitative radiochemical yield. The second step, deprotection of the catechol moiety with HCl and heat, yielded 60–90% of [11C]2 giving an overall incorporation yield from [11C]methyl triflate of 60–90%. In a typical run more than 1 GBq of [11C]2, was produced from carbon‐11 generated from a 10‐min proton irradiation (16 MeV; 35 µA) of nitrogen–hydrogen target gas. The radiochemical purity of [11C]2 was > 99% and specific radioactivity at the time of injection was 901±342 GBq/µmol (n=10). The total synthesis time was 35–38 min from the end of radionuclide production. The identity of [11C]2 was confirmed by comparing its LC‐MS/MS spectrum with those of reference 2 and (R)‐(−)‐10‐methoxy‐2,11‐dihydroxy‐N‐n‐propylnoraporphine. Copyright © 2009 John Wiley & Sons, Ltd.
Glucose‐dependent insulinotropic polypeptide (GIP) and its receptor (GIPR): Cellular localization, lesion‐affected expression, and impaired regenerative axonal growth
Authors: Buhren Bettina A. , Gasis Marcia , Thorens Bernard , Müller Hans Werner , Bosse Frank 
Published: January 2009

AbstractGlucose‐dependent insulinotropic polypeptide (GIP) was initially described to be rapidly regulated by endocrine cells in response to nutrient ingestion, with stimulatory effects on insulin synthesis and release. Previously, we demonstrated a significant up‐regulation of GIP mRNA in the rat subiculum after fornix injury. To gain more insight into the lesion‐induced expression of GIP and its receptor (GIPR), expression profiles of the mRNAs were studied after rat sciatic nerve crush injury in 1) affected lumbar dorsal root ganglia (DRG), 2) spinal cord segments, and 3) proximal and distal nerve fragments by means of quantitative RT‐PCR. Our results clearly identified lesion‐induced as well as tissue type‐specific mRNA regulation of GIP and its receptor. Furthermore, comprehensive immunohistochemical stainings not only confirmed and exceeded the previous observation of neuronal GIP expression but also revealed corresponding GIPR expression, implying putative modulatory functions of GIP/GIPR signaling in adult neurons. In complement, we also observed expression of GIP and its receptor in myelinating Schwann cells and oligodendrocytes. Polarized localization of GIPR in the abaxonal Schwann cell membranes, plasma membrane‐associated GIPR expression of satellite cells, and ependymal GIPR expression strongly suggests complex cell type‐specific functions of GIP and GIPR in the adult nervous system that are presumably mediated by autocrine and paracrine interactions, respectively. Notably, in vivo analyses with GIPR‐deficient mice suggest a critical role of GIP/GIPR signal transduction in promoting spontaneous recovery after nerve crush, insofar as traumatic injury of GIPR‐deficient mouse sciatic nerve revealed impaired axonal regeneration compared with wild‐type mice. © 2009 Wiley‐Liss, Inc.