bluuebunny/crossref_metadata_2025_split huggingface dataset:
O'Connell effect in early‐type contact binaries: DU Boo and AG Vir
Authors: Pribulla T. , Vaňko M. , Chochol D. , Hambálek Ľ. , Parimucha Š. 
Published: July 2011

AbstractThe paper presents new photoelectric observations of the eclipsing binary systems DU Boo and AG Vir. The systems are somewhat similar – both are A‐type contact binaries with the maximum following the primary minimum being the brighter one. This light curve asymmetry is extremely temporally stable. The phase dependence of the color indices is unexpectedly small for the observed amplitude of the O'Connell effect, amounting to about 0.1 mag in the optical wavelength range which indicates a very large heated area with a temperature contrast of ΔT ≈ 1000–1500 K. The broadening functions (BFs) of the systems do not show any dark solar‐type photospheric spots. On the other hand, there are significant differences of BFs between the quadratures (surprisingly similar in both systems) indicative of stream of matter or bright region causing additional emission seen between the components around the phase 0.25. Absolute parameters of the components slightly depend on the adopted model. Long orbital period of both contact binaries combined with late spectral type indicate that the primary components of either of the systems (but particularly in case of DU Boo) already evolved off the main sequence (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An Evaluation of Peptide‐Bond Isosteres
Authors: Choudhary Amit , Raines Ronald T. 
Published: July 2011

AbstractPeptide‐bond isosteres can enable a deep interrogation of the structure and function of a peptide or protein by amplifying or attenuating particular chemical properties. In this Minireview, the electronic, structural, and conformational attributes of four such isosteres—thioamides, esters, alkenes, and fluoroalkenes—are examined in detail. In particular, the ability of these isosteres to partake in noncovalent interactions is compared with that of the peptide bond. The consequential perturbations provide a useful tool for chemical biologists to reveal new structure–function relationships, and to endow peptides and proteins with desirable attributes.
Numerical simulation of the transient temperature distribution inside moving particles
Authors: Schmidt Robin , Nikrityuk Petr A. 
Published: July 2011

AbstractThis work is devoted to the two‐dimensional (2D) numerical simulation of heat and fluid flow by granular mixing in a horizontally rotating kiln. The heat and fluid flow in the gas phase are solved directly using a fixed Eulerian grid. At the same time, the particle dynamics and their collisions are solved on a Lagrangian grid. The no‐slip boundary condition on the particle surface is implemented using the fictitious boundary method. The heat transfer inside the particles is calculated utilising two models: the first is the direct solution of the energy conservation equation in Lagrangian and Eulerian space and the second is the so‐called linear model, which assumes a homogeneous distribution of the temperature inside each particle. Numerical simulations showed that if the thermal diffusivity of the gas phase significantly exceeds the same parameter of the particles, the linear model over‐predicts the heating rate of the particles. The analysis of the time‐averaged flow field inside the kiln showed that in the gas phase a double vortex structure is formed which increases the convective heat transfer in the upper part of the particulate bed. The influence of the particle size, the angular velocity of the drum and the fluid on the heating rates of particles is studied and discussed.
Kinetics, equilibrium and thermodynamic studies on the adsorptive removal of nickel, cadmium and cobalt from wastewater by superparamagnetic iron oxide nanoadsorbents
Authors: Nassar Nashaat N. 
Published: July 2011

AbstractBecause of its unique properties, such as specific functionality and large specific surface area, iron oxide nanoadsorbents had showed potential for energy and environmental applications. This work investigated the adsorptive removal of different metal ions from wastewater by superparamagnetic iron oxide nanoadsorbents (Fe3O4). Batch‐adsorption technique was employed to assess the kinetic behaviour and adsorption equilibrium of cadmium, cobalt and nickel. Accordingly, the effect of the following variables on the adsorption reaction was tested, namely: solution pH, contact time and temperature. Metal ion adsorption was found to be highly pH dependent with a maximum uptake achieved around pH 5.5. Kinetic studies showed that adsorption was fast and equilibrium was achieved in less than 60 min. The external mass transfer kinetic model was applied to the experimental results and provided reasonable overall volumetric mass transfer coefficients. Adsorption isotherms were determined and appropriately described by the Freundlich and Langmuir models, with a better fit to the Freundlich model. The amount of metal ion adsorbed increased as the temperature increased, suggesting an endothermic adsorption process. The thermodynamics studies indicated that the adsorption process was spontaneous and endothermic in nature. © 2011 Canadian Society for Chemical Engineering
From Activity Cliffs to Target‐Specific Scoring Models and Pharmacophore Hypotheses
Authors: Seebeck Birte , Wagener Markus , Rarey Matthias 
Published: July 2011

AbstractThe role of activity cliffs in drug discovery projects is certainly two‐edged: on the one hand, they often lead to the failure of QSAR modeling techniques; on the other, they are highly valuable for identifying key aspects of SARs. In the presence of activity cliffs the results of purely ligand‐based QSAR approaches often remain puzzling, and the resulting models have limited predictive power. Herein we present a new approach for the identification of structure‐based activity cliffs (ISAC). It uses the valuable information of activity cliffs in a structure‐based design scenario by analyzing interaction energies of protein–ligand complexes. Using the relative frequency at which a protein atom is involved in activity cliff events, we introduce a novel visualization of hot spots in the active site of a protein. The ISAC approach supports the medicinal chemist in elucidating the key interacting atoms of the binding site and facilitates the development of pharmacophore hypotheses. The hot spot visualization can be applied to small data sets in early project phases as well as in the lead optimization process. Based on the ISAC approach, we developed a method to derive target‐specific scoring functions and pharmacophore constraints, which were validated on independent external data sets in virtual screening experiments. The activity‐cliff‐based approach shows an improved enrichment over the generic empirical scoring function for various protein targets in the validation set.
SNP–SNP interactions between DNA repair genes were associated with breast cancer risk in a Korean population
Authors: Han Wonshik , Kim Kyoung‐Yeon , Yang Song‐Ju , Noh Dong‐Young , Kang Daehee , Kwack KyuBum 
Published: July 2011

AbstractBACKGROUND:Single nucleotide polymorphisms (SNPs) in nucleotide excision repair (NER) pathway genes may modulate DNA repair capacity and increase susceptibility to breast cancer (BC). A case‐control study was conducted by evaluating genes involved in DNA repair to identify polymorphisms associated with BC.METHODS:The 384 SNPs of 38 candidate genes were genotyped using the Illumina GoldenGate method. Genotypes were determined in a case‐control study that consisted of 346 BC patients and 361 controls. Odds ratios and 95% confidence intervals were computed using logistic regression models. Multiple logistic regression models adjusted for age, family history of BC, and body mass index were used.RESULTS:Gene–gene interaction analysis among the DNA repair pathway genes showed significant effects on BC risk. ERCC2 rs50872 (TC genotype) in combination with XPA rs2808668 (TC genotype) and rs1800975 (AG genotype) was strongly associated with an increased risk of BC (P = .0004 and .0002, PBonferroni = .023 and .014, respectively). Moreover, the T‐G (including rs2808668 and rs1800975) haplotype in XPA combined with the ERCC2 T allele in rs50872 carriers was also associated with additive risk effect of BC (odds ratios: 2.58, 2.62, and 3.49, respectively).CONCLUSION:Genetic variation in DNA repair genes involved in NER mechanisms increased the risk of BC development. These results suggested that a stronger combined effect of SNPs via gene–gene interaction may help to predict BC risk. Cancer 2012;. © 2011 American Cancer Society.
Novel antagonists of growth hormone‐releasing hormone inhibit growth and vascularization of human experimental ovarian cancers
Authors: Klukovits Anna , Schally Andrew V. , Szalontay Luca , Vidaurre Irving , Papadia Andrea , Zarandi Marta , Varga Jozsef L. , Block Norman L. , Halmos Gabor 
Published: July 2011

AbstractBACKGROUND:Antagonists of growth hormone‐releasing hormone (GHRH) inhibit the proliferation of various human cancer cell lines and experimental tumors by mechanisms that include direct action on GHRH receptors in cancer cells.METHODS:In this study, the effects of newly synthesized GHRH antagonists, MIA‐313, MIA‐602, MIA‐604, and MIA‐610, were investigated in 2 human ovarian epithelial adenocarcinoma cell lines, OVCAR‐3 and SKOV‐3, in vitro and in vivo. The expression of receptors for GHRH was demonstrated by Western blot analysis and ligand competition methods in the OVCAR‐3 and SKOV‐3 cell lines and in tumors from those cells grown in athymic nude mice. The effects of GHRH antagonists on the secretion of vascular endothelial growth factor (VEGF) by OVCAR‐3 cells and on the vascularization of OVCAR‐3 xenografts also were evaluated.RESULTS:Both the pituitary and the splice variant type 1 (SV1) GHRH receptors were detected in the 2 cell lines and in tumor xenografts, and SV1 was expressed at higher levels. Cell viability assays revealed the antiproliferative effect of all GHRH antagonists that were. Maximal tumor growth inhibition was approximately 75% in both models. MIA‐313 and MIA‐602 decreased VEGF secretion of OVCAR‐3 cells, as measured by enzyme‐linked immunosorbent assay, and reduced tumor vascularization in a Matrigel plug assay, but caused no change in the expression of VEGF or VEGF receptor in the terminal ileum of mice with OVCAR‐3 tumors.CONCLUSIONS:Results from the current study indicated that a he novel approach based on GHRH antagonists may offer more effective therapeutic alternatives for patients with advanced ovarian cancer and who do not tolerate conventional anti‐VEGF therapy. Cancer 2012;. © 2011 American Cancer Society.
Rates and predictors of colorectal cancer screening by race among motivated men participating in a prostate cancer risk assessment program
Authors: Hall Michael J. , Ruth Karen , Giri Veda N. 
Published: July 2011

AbstractBACKGROUND:Screening by fecal occult blood test and lower endoscopy has lowered colorectal cancer (CRC) mortality, but compliance gaps persist. Of concern are possible disparities in uptake of CRC screening between white and African American men. The goal of this study was to assess for disparities in uptake of CRC screening among men participating in a high‐risk prostate cancer clinic. If present, such disparities could support hypotheses for further research examining racial differences in awareness and patient preferences in undergoing CRC screening.METHODS:Baseline data on a racially diverse cohort of men aged 50 to 69 years at increased risk of prostate cancer collected via the Prostate Cancer Risk Assessment Program at Fox Chase Cancer Center were analyzed. Predictors of uptake of CRC screening were assessed using multivariate logistic regression.RESULTS:Compared with whites, African American men had statistically significantly lower uptake of fecal occult blood testing (African American 49.0% vs white 60.7%, P = .035), lower endoscopy (African American 44.1% vs white 58.5%, P = .011), and any CRC screening (African American 66.2% vs white 76.3%, P = .053). Predictors of uptake of lower endoscopy among African American men included older age (odds ratio [OR], 3.61; 95% confidence interval [CI], 1.87‐6.97), family history of CRC (OR, 3.47; 95% CI, 1.30‐9.25), and insurance status (OR, 1.90; 95% CI, 1.04‐3.46).CONCLUSIONS:Despite awareness of cancer risk and motivation to seek prostate cancer screening through a specialized prostate cancer risk assessment program, evidence supporting compliance gaps with CRC screening among men was found. Tailored messages to younger African American men with and without a family history of CRC are needed. Cancer 2011;. © 2011 American Cancer Society.
Racial and ethnic differences in lymph node examination after colon cancer resection do not completely explain disparities in mortality
Authors: Rhoads Kim F. , Cullen Jennifer , Ngo Justine V. , Wren Sherry M. 
Published: July 2011

AbstractBACKGROUND:In 1999, a multidisciplinary panel of experts in colorectal cancer reviewed the relevant medical literature and issued a consensus recommendation for a 12‐lymph node (LN) minimum examination after resection for colon cancer. Some authors have shown racial/ethnic differences in receipt of this evidence‐based care. To date, however, none has investigated the correlation between disparities in LN examination and disparities in outcomes after colon cancer treatment.METHODS:This retrospective analysis used California Cancer Registry linked to California Office of Statewide Health Planning and Development discharge data (1996‐2006). Chi‐square analysis, logistic regression, and Cox proportional hazard models predicted disparities in receipt of an adequate examination and the effect of an inadequate exam on mortality and disparities. Patients with stage I and II colon cancers undergoing surgery in California were included; patients with stage III and IV disease were excluded.RESULTS:A total of 37,911 records were analyzed. Adequate staging occurred in fewer than half of cases. An inadequate examination (<12 LNs) was associated with higher mortality rates. Hispanics had the lowest odds of receiving an adequate exam; however, blacks, not Hispanics, had the highest risk of mortality compared with whites. This disparity was not completely explained by inadequate LN examination.CONCLUSIONS:Inadequate LN exam occurs often and is associated with increased mortality. There are disparities in receipt of the minimum exam, but this only explains a small part of the observed disparity in mortality. Improving the quality of LN examination alone is unlikely to correct colon cancer disparities. Cancer 2011;. © 2011 American Cancer Society.
A nomogram to predict postresection 5‐year overall survival for patients with uterine leiomyosarcoma
Authors: Zivanovic Oliver , Jacks Lindsay M. , Iasonos Alexia , Leitao Mario M. , Soslow Robert A. , Veras Emanuela , Chi Dennis S. , Abu‐Rustum Nadeem R. , Barakat Richard R. , Brennan Murray F. , Hensley Martee L. 
Published: July 2011

AbstractBACKGROUND:The clinical course of patients with uterine leiomyosarcoma (LMS) is difficult to predict with the currently available categorical staging systems of the American Joint Committee on Cancer (AJCC) and the International Federation of Gynecology and Obstetrics (FIGO). The objective of the current study was to develop and validate a novel, clinically relevant, individualized prognostic model for patients with uterine LMS.METHODS:Patients with uterine LMS who presented at the authors' institution from 1982 to 2008 were analyzed. The nomogram model was chosen based on the clinical evidence and statistical significance of the predictors, including age at diagnosis, tumor size, histologic grade, uterine cervix involvement, extrauterine spread, distant metastases, and mitotic index. Five‐year overall survival (OS) was the predicted endpoint. The concordance probability (CP) was used as a predictive accuracy measure and compared with the CP of current staging systems. The model was internally validated using 200 bootstrap samples to correct for over fitting.RESULTS:One hundred eighty‐five of 270 patients were eligible for the nomogram analysis. The median follow‐up was 5.4 years, and the median OS was 3.75 years (95% confidence interval, 3‐6 years). The CP of the newly developed nomogram was 0.67 (95% confidence interval, 0.63‐0.72). This was superior to predictions based on AJCC and FIGO staging. The bootstrap‐validated CP was 0.65 with good calibration accuracy.CONCLUSIONS:The authors developed and internally validated a uterine LMS‐specific nomogram to predict 5‐year OS. This novel, individualized prognostic model outperforms traditionally used categorical staging systems and may be useful for patient counseling and for better selection of patients for adjuvant therapy trials. Cancer 2012;. © 2011 American Cancer Society.
Phase 2 Southwest Oncology Group‐directed intergroup trial (S0505) of sorafenib in advanced soft tissue sarcomas
Authors: von Mehren Margaret , Rankin Cathryn , Goldblum John R. , Demetri George D. , Bramwell Vivien , Ryan Christopher W. , Borden Ernest 
Published: July 2011

AbstractBACKGROUND:Patients with advanced soft tissue sarcomas (STS) have limited therapeutic options. Sorafenib (BAY 43‐9006) is a multitargeted tyrosine kinase inhibitor of raf, vascular endothelial growth factor receptors 1 (VEGFR1) through 3, platelet‐derived growth factor B, fms‐like tyrosine kinase 3, and c‐kit, and some of these may be relevant in STS.METHODS:The authors tested sorafenib at a dose of 400 mg twice daily in patients with advanced vascular sarcoma (VS), high‐grade liposarcomas, and leiomyosarcomas who had received 0 or 1 previous regimens for advanced disease.RESULTS:Fifty‐one patients were accrued to the study, and 37 were evaluable for toxicity and response. There were no unexpected side effects and no confirmed responses. The median progression‐free survival was 3 months, and the median overall survival was 17 months. Six of 8 patients in the VS cohort had prolonged clinical benefit (stable disease or better), resulting in a median progression‐free survival of 5 months compared with 2 to 3 months for the patients who had liposarcoma and leiomyosarcomas.CONCLUSIONS:Sorafenib at the dose and schedule studied did not result in any responses in the VS, liposarcoma, or leiomyosarcoma cohort according to Response Evaluation Criteria in Solid Tumors. Cancer 2012;. © 2011 American Cancer Society.
Synergistic inhibitory effect of apomine and lovastatin on osteosarcoma cell growth
Authors: Moriceau Gatien , Roelofs Anke J. , Brion Régis , Redini Françoise , Ebetion Frank H. , Rogers Michael J. , Heymann Dominique 
Published: July 2011

AbstractBACKGROUND:Osteosarcoma is the most frequent malignant primary bone tumor that occurs mainly in the young, with an incidence peak observed at age 18 years. Both apomine and lovastatin have antitumor activity in a variety of cancer cell lines. Apomine, a 1,1‐bisphosphonate‐ester, increases the rate of degradation of 3‐hydroxy‐3 methylglutaryl‐coenzyme A (HMG‐CoA) reductase, the rate‐limiting enzyme in the mevalonate pathway, whereas lovastatin competitively inhibits HMG‐CoA reductase enzyme activity, thereby preventing protein prenylation and cholesterol synthesis.METHODS:The authors of this report investigated the effect of combined treatment with apomine and lovastatin in vitro on human and murine osteosarcoma cell lines and in vivo using a murine syngeneic model of osteosarcoma. Apomine and lovastatin synergistically decreased viability and induced apoptosis in both murine and human osteosarcoma cell lines.RESULTS:Combined apomine and lovastatin strongly decreased HMG‐CoA reductase enzyme levels compared with lovastatin treatment alone. Consequently, the accumulation of unprenylated ras‐related protein 1A induced by lovastatin was enhanced in the presence of apomine. All synergistic effects on cell viability, apoptosis, and protein prenylation were overcome by the addition of mevalonate or geranylgeraniol, 2 mevalonate pathway intermediates downstream from the target enzyme, HMG‐CoA reductase. This confirmed that the mechanism of synergy in osteosarcoma cells is through augmented inhibition of HMG‐CoA reductase. Finally, treatment of POS‐1 osteosarcoma‐bearing mice with a combination of apomine and lovastatin significantly reduced tumor progression in these mice compared with single treatments, which had no effect at the doses used.CONCLUSIONS:The results from this study revealed that combination therapy with apomine and lovastatin may be a novel treatment strategy for osteosarcoma. Cancer 2012;. © 2011 American Cancer Society.
Management of malignant colonic polyps: A population‐based analysis of colonoscopic polypectomy versus surgery
Authors: Cooper Gregory S. , Xu Fang , Barnholtz Sloan Jill S. , Koroukian Siran M. , Schluchter Mark D. 
Published: July 2011

AbstractBACKGROUND:The management of colon polyps containing invasive carcinoma includes surgical resection or colonoscopic polypectomy. To date, there are very limited population‐based data comparing outcomes with the 2 management approaches.METHODS:Using the linked Surveillance Epidemiology and End Results–Medicare database, we identified 2077 patients aged ≥66 years with an initial diagnosis of stage T1N0M0 malignant polyp from 1992‐2005. Patients were categorized as surgical or polypectomy depending on the most invasive treatment. To adjust for potential selection bias in treatment assignment, using multivariate analysis, patients were divided into quintiles of likelihood of polypectomy (propensity scores), and outcomes were compared in each quintile.RESULTS:Surgical resection was performed in 1340 (64.5%) patients and polypectomy was performed in 737 (35.5%) patients. Predictors for undergoing polypectomy (P<.001) included older age, greater comorbidity, no history of polyps, diagnosis in 2002 or later, left colon site of cancer, well‐differentiated tumors, and colonoscopy performed in an outpatient setting. Both 1‐year and 5‐year survival were higher in the surgical group (92% and 75%, respectively) than in the polypectomy group (88% and 62%, respectively). The unadjusted hazard ratio was 1.51 (95% confidence interval [CI], 1.31‐1.74). After adjusting for propensity quintile, the hazard ratio was 1.15 (95% CI, 0.98‐1.33). Within each propensity quintile, the risk of death was similar between the 2 groups (interaction test P = .96).CONCLUSIONS:In this large, population‐based sample, more than one‐third of patients with malignant polyps were treated with colonoscopic polypectomy. Outcomes were similar to surgical patients with comparable clinical characteristics and could be offered to patients who meet appropriate clinical criteria. Cancer 2012;. © 2011 American Cancer Society.