bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interindividual variability of arterial impulse response to intravenous injection of nonionic contrast agent (Iohexol) in DCE‐CT study
Authors: Kim S. M. , Haider M. A. , Milosevic M. , Yeung I. W. T. 
Published: September 2009

Purpose:It is known that the arterial input function (AIF) in dynamic contrast‐enhanced (DCE)‐CT differs among patients even for fixed contrast injection protocols. Therefore, a study has been performed to investigate the interindividual variability of the AIF with respect to patient factors (such as weight, height, and age). In addition, it has been demonstrated that the relations from the interindividual variability investigation can be further used for the estimation of AIF for a patient without the requirement of measurement.Methods:DCE‐CT data for a cohort of 34 patients with cervical carcinoma were used for the investigation of interindividual variability of the AIF. To dissociate the effect of different durations of contrast injection, the arterial impulse response (AIR) to intravenous contrast injection was calculated and examined for its correlations with these patient factors. An empirical functional form was proposed to model the AIR with temporal intensity of a first pass of contrast agent followed by recirculation and quasiequilibrium state of contrast concentration. Specific features (onset time, peak time, and amplitudes) of the AIR were tested for correlations with the patient factors. Linear regression was applied to cases that show significant strong correlation between the AIR amplitudes and patient factors. The results were then used to predict the AIR for any given patient based on the patient factors. It was shown that using the predicted AIR, the AIF of the patient can be estimated without the requirement of measurement given the injection protocol is known. The method of AIF estimation was tested in DCE‐CT data from another group of 14 patients. The efficacy of individually estimated AIF on pharmacokinetic analysis was assessed against the use of measured AIF and population‐averaged AIF as the latter is another possible strategy for AIF generation if AIF measurement is not available.Results:It was found that the amplitudes of AIR postonset time were significantly correlated with patient bodyweight at most time pointsexcept 8–17 s. When the adiabatic tissue homogeneity (ATH) and the Kety models were applied to the pharmacokinetic analysis, the mean percentage errors in kinetic parameter estimates induced by using the estimated AIF instead of the measured one for both models ranged from −4.98% to 11.19 %.Conclusions:It was found that there are strong linear relationships between AIR and patient weight; thereby the AIR of a patient can be estimated with patient weight. The proposed method of AIF estimation is potentially applicable in cases where AIF measurement is not possible.
Severe food restriction induces myocardial dysfunction related to SERCA2 activity
Authors: Sugizaki Mário Mateus , Leopoldo André Soares , Okoshi Marina Politi , Bruno Alessandro , Conde Sandro José , Lima-Leopoldo Ana Paula , Padovani Carlos Roberto , Carvalho Robson Francisco , Nascimento André Ferreira do , Campos Dijon Henrique Salomé de , Nogueira Célia Regina , Cicogna Antonio Carlos 
Published: September 2009

Previous studies have shown that food restriction promotes myocardial dysfunction in rats. However, the molecular mechanisms that are responsible are unclear. We investigated the role of sarcoplasmic reticulum Ca2+-ATPase (SERCA2) on myocardial performance in food-restricted rats. Male Wistar–Kyoto rats, 60 days old, were fed a control or restricted diet (daily energy intake reduced to 50% of the control) for 90 days. Expression of Serca2a, phospholamban (PLB), Na+/Ca2+exchanger (NCX), and thyroid hormone receptor (TRα1, TRβ1) mRNA was determined by quantitative PCR. SERCA2 activity was measured by using 20 µmol/L cyclopiazonic acid (CPA) in a left ventricular papillary muscle preparation during isometric contraction in basal conditions and during post-rest contraction. Serum concentrations of thyroxine (T4) and thyrotropin (TSH) were also determined. The 50%-restricted diet reduced body and ventricular weight and serum T4and TSH levels. The interaction of CPA and food restriction reduced peak developed tension and maximum rate of tension decline (–dT/dt), but increased the resting tension intensity response during post-rest contraction. PLB and NCX mRNA were upregulated and TRα1 mRNA was downregulated by food restriction. These results suggest that food restriction promotes myocardial dysfunction related to impairment of sarcoplasmic reticulum Ca2+uptake as a result of a hypothyroid state.
Tumor cells expressing tissue factor influence the migration of smooth muscle cells in a catalytic activity-dependent way
Authors: Brousseau Catherine , Morissette Guillaume , Fortin Jean-Philippe , Marceau François , Petitclerc Eric 
Published: September 2009

The expression of tissue factor (TF) in tumors reportedly exacerbates the agressiveness of several types of cancers. The shedding of TF-containing membrane particles is believed to influence the ability of tumors to expand and metastasize, and these microparticles may also be harmful in the onset of disseminated intravascular coagulation in specific cancers. Futhermore, the intracellular signaling that is elicited after the formation of the TF / coagulation factor VIIa complex at the cell membane modulates the activity of adhesion molecules and mitogen-activated protein (MAP) kinases. To evaluate whether TF overexpression in tumor cells modulates its shedding and neighboring stromal cells by its catalytic or intracellular activity, TF-GFP (green fluorescent protein) and a tailless form (TFΔC-GFP) were stably expressed in the rat Morris hepatoma and human HT1080 fibrosarcoma cell lines. Both TF proteins were efficiently produced by tumor cells and functionally active, and their clotting activity could be blocked by the active site-inhibited factor VIIa (ASIS). TF-expressing tumorigenic cells produced a soluble factor that increased the migration of arterial smooth muscle cells in vitro. This effect was abrogated by ASIS and the PAR-1 receptor antagonist ATAP-2, showing that it is dependent on the proteolytic activity of the TF ligand factor VIIa and the thrombin-activated cell membrane receptor. We propose that TF-containing microparticles that are released in the culture medium by tumor cells influence the migratory behavior of neighboring stromal cells, thus aiding the cancer cell’s tumorigenic potential.
Behavioral response of migrating wood frogs to experimental timber harvest surrounding wetlands
Authors: Rittenhouse Tracy A.G. , Semlitsch Raymond D. 
Published: September 2009

Behavioral responses to ecological disturbances such as timber harvest, fire, or drought provide insight into wildlife habitat requirements. To determine the behavioral response of adult wood frogs ( Lithobates sylvatica (LeConte, 1825)) to timber harvest in oak–hickory forest, we conducted experimental timber harvest surrounding replicate breeding sites, monitored freely moving frogs using radiotelemetry, and tested the repeatability of behavioral responses with two experimental displacements. We found no evidence that wood frogs use recent oak–hickory clearcuts as habitat. Timber harvest was not a complete barrier to movement, as frogs surviving increased predation and desiccation risks reached drainages used as nonbreeding habitat. Frogs did not alter the direction of travel and traversed similar distances (i.e., total distance and net distance from breeding site) before and after timber harvest. However, rate of travel (i.e., maximum distance traversed in 1 day) increased following timber harvest and frogs displaced to the center of clearcuts exited the timber harvest array in one rainy night. Notably, wood frogs following displacement exhibited site fidelity to nonbreeding habitat. We suggest that deleterious effects of timber harvest on amphibians may be minimized through the use of small stand sizes placed in locations that do not separate breeding and nonbreeding habitat.
Diets and distributions of Leach’s storm-petrel (Oceanodroma leucorhoa) before and after an ecosystem shift in the Northwest Atlantic
Authors: Hedd A. , Montevecchi W. A. , Davoren G. K. , Fifield D. A. 
Published: September 2009

The Grand Bank ecosystem has undergone significant shifts during the past two decades owing to oceanographic and fishing effects. Effects on upper trophic level seabirds (dietary shifts, reduced reproductive performance) have been mediated through changes in the biology and behaviour of capelin ( Mallotus villosus (Müller, 1776)), the focal forage species. To explore for effects at lower trophic levels, we combine dietary (1987–1988, 2003–2006) and distributional (1966–1990, 1998–1999) data for Leach’s storm-petrel ( Oceanodroma leucorhoa (Vieillot, 1818)), a small, abundant, and highly pelagic seabird. Fish and crustaceans formed the bulk of nestling diet at two colonies, with fish dominating in all sampling periods and years (occurrence >70%, reconstructed mass >75%). Five families were represented, but mature myctophids (glacier lanternfish ( Benthosema glaciale (Reinhardt, 1837)), horned lanternfish ( Ceratoscopelus maderensis (Lowe, 1839)), Protomyctophum arcticum (Lütken, 1892)) and sandlance (genus Ammodytes L., 1758) dominated. Crustaceans occurred frequently but typically comprised ≤10% by mass; Hyperia galba (Montagu, 1813) dominated this prey class. General diet composition was similar through time with birds relying heavily on myctophid fishes in 1987–1988 and 2003–2006. Crustacean diversity, however, declined with fewer species of hyperiid amphipods and no small euphausiids (genus Thysanoessa Brandt, 1851) consumed in 2003–2006. The latter parallels changes in spring diets of capelin and winter diets of murres (genus Uria Brisson, 1760) in the region. Associations of storm-petrels with deep water are consistent with the predominance of mesopelagic prey in their diets.
Butyric acid suppresses palatable food consumption in Siberian hamsters (Phodopus sungorus) housed in short, but not long, photoperiods
Authors: Workman Joanna L. , Johnson Eric M. , Martin Lynn B. , Nelson Randy J. 
Published: September 2009

Short days induce winter-like adaptations in small mammals such as Siberian hamsters ( Phodopus sungorus (Pallas, 1773)). Specifically, hamsters adjust food consumption, metabolic processes, and immune function to optimize energetic needs and promote winter survival. One potentially inexpensive behavioral adaptation to increase survival is avoidance of infection. We tested the hypothesis that photoperiod affects avoidance of potentially infected food. In experiment 1, hamsters were weaned into either short or long days with ad libitum food. Three weeks later, hamsters were presented with either skim milk treated with butyric acid (2%), a bacterial product that serves as a potent cue of spoilage, or unadulterated skim milk; consumption was measured. After milk presentation, blood samples were obtained to assess cortisol. In experiment 2, skim-milk consumption was again assessed after 3 weeks in either short or long days. In experiment 3, we tested the hypothesis that food avoidance was due to photoperiod-induced differential neophobia. Short-day hamsters increased milk consumption, which was blocked by butyric acid. Short days increased cortisol concentrations; neither food restriction nor butyric acid affected cortisol concentrations. Photoperiod did not alter neophobic responses. These experiments suggest that short-day hamsters avoid food treated with butyric acid possibly as an adaptive trait to avoid costly winter infections.
Population genetic structure of raccoons (Procyon lotor) inhabiting a highly fragmented landscape
Authors: Dharmarajan Guha , Beasley James C. , Fike Jennifer A. , Rhodes Olin E. 
Published: September 2009

The raccoon ( Procyon lotor (L., 1758)), a generalist mesocarnivore, has thrived in anthropogenically fragmented landscapes. In this study we utilized 13 microsatellites to analyze the population genetic structure in raccoons occupying an agriculturally fragmented habitat. Our analyses revealed low, but significant, levels of genetic structure (FST = 0.022, P < 0.001) among 645 raccoons inhabiting 29 spatially distinct habitat patches (neighborhoods). We found no evidence for the presence of either isolation by distance or barriers. However, spatial autocorrelation revealed evidence for social structure at the raccoon-neighborhood scale. About 30% of the variance in levels of social structure among raccoon neighborhoods was explained by effects of habitat-patch size and the percentage of land cover represented by forest around the individual habitat patch. We found strong evidence of sex-biased dispersal using direct (parentage analysis) and indirect (relatedness and assignment indices) genetic estimators. However, our analysis revealed that among dispersing raccoons there was no difference in dispersal distance between sexes and that dispersal events are randomly distributed with respect to distance. Our study provides evidence that demographic and behavioral processes affecting raccoon spatial organization may be most critical at very fine scales of biological organization, such as within individual habitat patches.
The Impact of Auditors' Opinions, Macroeconomic and Industry Factors on Financial Distress Prediction: An Empirical Investigation
Authors: Tsai Bi-Huei , Lee Cheng-Few , Sun Lili 
Published: September 2009

This study investigates the usefulness of auditors' opinions, market factors, macroeconomic factors, and industry factors in predicting financial distress of Taiwanese firms. Specifically, two non-traditional auditors' opinions are evaluated: "long-term investment audited by other auditors" ("other auditor"), and "realized investment income based on non-audited financial statements" ("no auditor").The results of the 22 discrete-time hazard models show that "other auditor" opinions have incremental contribution in predicting financial distress, in addition to "going concern" opinions. This suggests that "other auditor" opinions possess higher risk of overstating earnings and firms with such income items are more likely to fail. Besides, we find that the macroeconomic factors studied significantly explain financial distress. Particularly, the survivals of electronic firms are more sensitive to earnings due to higher earnings fluctuations in such firms. Finally, models with auditors' opinions, market factors, macroeconomic factors, and industry factors perform better than the financial ratio-only model in financial distress prediction.
Are Structural VARs with Long-Run Restrictions Useful for Developing Monetary Policy Strategy in Egypt?
Authors: Hachicha Ahmed , Lee Cheng-Few 
Published: September 2009

On the basis of SVAR models of monetary policy in Egypt for the period December 1976–May 2006, our paper explores a new empirical assessment for the interest rate channel in correcting trouble in the Egyptian economy by imposing contemporaneous and long run restrictions. It appears that after a monetary policy expansion, output is stable in the first period, rises temporarily reaching the baseline at t = 40, and the global monetary aggregate rises but not significantly. In addition, the price level rises with great difficulties in response to a negative interest rate shock to the global liquidity aggregate. The excess of money supply has a transitory effect on the Egyptian output but it causes inflation pressures. SVAR Blanchard and Quah (1989) estimation reveals contradictory results to the previous findings. Last but certainly not least, this means that the effect of bank lending and the interest rate channels on the economy are limited in time. The paper shows that the transmission of monetary policy through the interest rate channel has become weak in the short run but more important in the long run. Nonetheless, the bank lending channel through the commercial bank lending is not a potent monetary transmission mechanism.
Expression of Insulin Receptor Isoform A and Insulin-like Growth Factor-1 Receptor in Human Acute Myelogenous Leukemia: Effect of the Dual-Receptor Inhibitor BMS-536924 In vitro
Authors: Wahner Hendrickson Andrea E. , Haluska Paul , Schneider Paula A. , Loegering David A. , Peterson Kevin L. , Attar Ricardo , Smith B. Douglas , Erlichman Charles , Gottardis Marco , Karp Judith E. , Carboni Joan M. , Kaufmann Scott H. 
Published: September 2009

Abstract
The insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R) are receptor tyrosine kinases that participate in mitogenic and antiapoptotic signaling in normal and neoplastic epithelia. In the present study, immunoblotting and reverse transcription-PCR demonstrated expression of IGF1R and IR isoform A in acute myelogenous leukemia (AML) cell lines as well as in &gt;80% of clinical AML isolates. Treatment with insulin enhanced signaling through the Akt and MEK1/2 pathways as well as survival of serum-starved AML cell lines. Conversely, treatment with BMS-536924, a dual IGF1R/IR kinase inhibitor that is undergoing preclinical testing, inhibited constitutive receptor phosphorylation as well as downstream signaling through MEK1/2 and Akt. These changes inhibited proliferation and, in some AML cell lines, induced apoptosis at submicromolar concentrations. Likewise, BMS-536924 inhibited leukemic colony formation in CD34+ clinical AML samples in vitro. Collectively, these results not only indicate that expression of IGF1R and IR isoform A is common in AML but also show that interruption of signaling from these receptors inhibits proliferation in clinical AML isolates. Accordingly, further investigation of IGF1R/IR axis as a potential therapeutic target in AML appears warranted. [Cancer Res 2009;69(19):7635–43]
An A13 Repeat within the 3′-Untranslated Region of Epidermal Growth Factor Receptor (EGFR) Is Frequently Mutated in Microsatellite Instability Colon Cancers and Is Associated with Increased EGFR Expression
Authors: Yuan Ziqiang , Shin Joongho , Wilson Andrew , Goel Sanjay , Ling Yi-He , Ahmed Naseem , Dopeso Higinio , Jhawer Minaxi , Nasser Shannon , Montagna Cristina , Fordyce Kenneth , Augenlicht Leonard H. , Aaltonen Lauri A. , Arango Diego , Weber Thomas K. , Mariadason John M. 
Published: September 2009

Abstract
Colorectal cancers (CRC) with microsatellite instability (MSI) have clinical, pathologic, genetic, and epigenetic features distinct from microsatellite-stable CRC. Examination of epidermal growth factor receptor (EGFR) mRNA and protein expression levels in a panel of colon cancer cell lines identified strong expression of EGFR in multiple cell lines with MSI. Although no relationship between EGFR overexpression and the length of a CA dinucleotide repeat in intron 1 was observed, a variant A13/A14 repeat sequence within the 3′-untranslated region (3′-UTR) of the EGFR gene was identified, which was mutated by either mononucleotide or dinucleotide adenosine deletions in 64% of MSI cell lines and 69% of MSI colon tumors. Using a Tet-Off system, we show that this mutation increases EGFR mRNA stability in colon cancer cells, providing a mechanistic basis for EGFR overexpression in MSI colon cancer cell lines. To determine whether this mutation is a driver or a bystander event in MSI colon cancer, we examined the effect of pharmacologic and molecular inhibition of EGFR in EGFR 3′-UTR mutant MSI cell lines. Cell lines with an EGFR 3′-UTR mutation and that were wild-type (WT) for downstream signaling mediators in the Ras/BRAF and PIK3CA/PTEN pathways were sensitive to EGFR inhibition, whereas those harboring mutations in these signaling mediators were not. Furthermore, in cell lines WT for downstream signaling mediators, those with EGFR 3′-UTR mutations were more sensitive to EGFR inhibition than EGFR 3′-UTR WT cells, suggesting that this mutation provides a growth advantage to this subset of MSI colon tumors. [Cancer Res 2009;69(19):7811–8]
Role of SV40 Integration Site at Chromosomal Interval 1q21.1 in Immortalized CRL2504 Cells
Authors: Liu Jinglan , Kaur Gurpreet , Zhawar Vikramjit K. , Zimonjic Drazen B. , Popescu Nicholas C. , Kandpal Raj P. , Athwal Raghbir S. 
Published: September 2009

Abstract
We have applied a functional gene transfer strategy to show the importance of viral integration site in cellular immortalization. The large tumor antigen of SV40 is capable of extending the cellular life span by sequestering tumor suppressor proteins pRB and p53 in virus-transformed human cells. Although SV40 large T antigen is essential, it is not sufficient for cellular immortalization, suggesting that additional alterations in cellular genes are required to attain infinite proliferation. We show here that the disruption of human chromosomal interval at 1q21.1 by SV40 integration can be an essential step for cellular immortalization. The transfer of a 150-kb bacterial artificial chromosome (BAC) clone, RP364B14, corresponding to viral integration site in CRL2504 cells, reverted their immortal phenotype. Interestingly, the BAC transfer clones of CRL2504 cells displayed characteristics of either senescence as shown by β-galactosidase activity or apoptosis as revealed by positive staining with M30 CytoDEATH antibody. The SV40 integration at 1q21.1, in the vicinity of epidermal differentiation complex (EDC) genes, resulted in the down-regulation of the filaggrin (FLG) gene that is part of the EDC. FLG gene expression was increased in BAC transfer senescent and apoptotic clones. Our results suggest that the disruption of native genomic sequence by SV40 may alter expression of genes involved in senescence and apoptosis by modulating chromatin structure. These studies imply that identification of genes located in the vicinity of viral integration sites in human cancers may be helpful in developing new diagnostic and therapeutic strategies. [Cancer Res 2009;69(19):7819–25]
Human Suppressor of Cytokine Signaling 1 Controls Immunostimulatory Activity of Monocyte-Derived Dendritic Cells
Authors: Hong Bangxing , Ren Wenhong , Song Xiao-Tong , Evel-Kabler Kevin , Chen Si-Yi , Huang Xue F. 
Published: September 2009

Abstract
Dendritic cell (DC)–based tumor vaccines have only achieved limited clinical efficacy, underscoring the limitation of stimulatory strategies to elicit effective cytotoxic T lymphocyte (CTL) responses against self-tumor–associated antigens. Here, we investigate the role of human suppressor of cytokine signaling 1 (SOCS1), a feedback inhibitor of the Janus-activated kinase/signal transducer and activator of transcription signaling pathway, in regulating antigen presentation by human DCs (hDC). We find that human SOCS1 (hSOCS1)–silenced DCs have an enhanced stimulatory ability to prime self-antigen–specific CTLs in vitro and in a severe combined immunodeficient-hu mouse model. Human CTLs activated by SOCS1-silenced DCs, but not wild-type DCs, have an active lytic activity to natural antigen-expressing tumor cells. We further find that the capacity of hDCs to prime CTLs is likely controlled by SOCS1-restricted production and signaling of proinflammatory cytokines, such as interleukin-12. These results indicate a critical role of hSOCS1 in negatively regulating the immunostimulatory capacity of DCs and imply a translational potential of this alternative SOCS1 silencing strategy to develop effective DC vaccines. [Cancer Res 2009;69(20):8076–84]