A Comparative Study of the Properties of Polar and Nonpolar Solvent/Solute/Polystyrene Solutions in Microwave Fields Via Molecular Dynamics

The influence of an applied microwave field on the dynamics of methylamine-dichloromethane (DCM) mixtures bound within atactic polystyrene (a-PS) over a range of polymer densities from 30 to 94 wt % polymer was examined using atomistic molecular dynamics simulations. This study is an extension of previous studies on methylamine transport in relatively polar polystyrene solutions of methanol and dimethylformamide [M. J. Purdue et al., J. Chem. Phys. 124, 204904 (2006)]. A direct comparison is made across the three types of polystyrene solutions. Consideration is given to both solvent and reagent transport within the polymer solutions under zero-field conditions and in an external electromagnetic field in the canonical ensemble (NVT) at 298.0 K. Various frequencies up to 104 GHz and a rms electric field intensity of 0.1 V/Å were applied. The simulation studies were validated by comparison of the simulated zero-field self-diffusion coefficients of DCM in a-PS with those obtained using pulsed-gradient spin-echo NMR spectrometry. Athermal effects of microwave fields on solute transport behavior within polymer solutions are discussed

Molecular Dynamics of Polystyrene Solutions in Microwave Fields

Equilibrium and nonequilibrium molecular dynamics simulation techniques were used to assess the influence of an applied microwave field on the dynamics of methylamine-methanol and methylamine-dimethylformamide (DMF) solutions bound within atactic polystyrene over a range of polymer densities from 35 to 96 wt % polymer. Atomistically detailed systems were studied, ranging from 3000 to 10 644 particles, using previously established potential models. Structural and dynamical properties were determined in the canonical (NVT) ensemble at 298 K. The simulated DMF self-diffusion coefficients in polystyrene solutions were compared with the zero-field experimental results established with pulsed-gradient spin-echo NMR spectrometry. A simulated external microwave field, with a rms electric field intensity of 0.1 V/Å, was applied to these systems and the simulated dynamical results over field frequencies up to 104 GHz were compared with the zero-field values. Simulated evidence of athermal effects on the diffusive characteristics of these mixtures is reported

Circulating resistin levels and risk of multiple myeloma in three prospective cohorts

BACKGROUND: Resistin is a polypeptide hormone secreted by adipose tissue. A prior hospital-based case-control study reported serum resistin levels to be inversely associated with risk of multiple myeloma (MM). To date, this association has not been investigated prospectively. METHODS: We measured resistin concentrations for pre-diagnosis peripheral blood samples from 178 MM cases and 358 individually matched controls from three cohorts participating in the MM cohort consortium. RESULTS: In overall analyses, higher resistin levels were weakly associated with reduced MM risk. For men, we observed a statistically significant inverse association between resistin levels and MM (odds ratio, 0.44; 95% confidence interval (CI) 0.24-0.83 and 0.54; 95% CI 0.29-0.99, for the third and fourth quartiles, respectively, vs the lowest quartile; Ptrend=0.03). No association was observed for women. CONCLUSIONS: This study provides the first prospective evidence that low circulating resistin levels may be associated with an increased risk of MM, particularly for men

Aspirin, ibuprofen, and reduced risk of advanced colorectal adenoma incidence and recurrence and colorectal cancer in the PLCO Cancer Screening Trial

BACKGROUND: Studying the differential impact of aspirin and other nonsteroidal anti-inflammatory drugs across the stages of colorectal neoplasia from early adenoma to cancer is critical for understanding the benefits of these widely used drugs. METHODS: With 13 years of follow-up, the authors prospectively evaluated the association between aspirin and ibuprofen use and incident distal adenoma (1221 cases), recurrent adenoma (862 cases), and incident colorectal cancer (CRC; 2826 cases) among men and women in the population-based Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. With multivariable-adjusted models, odds ratio (ORs) and 95% confidence intervals (CIs) for adenoma incidence and recurrence and hazard ratios (HRs) and 95% CIs for incident CRC were determined. RESULTS: The authors observed a significantly reduced risk of incident adenoma with ibuprofen use (≥30 vs \u3c4 pills per month: OR, 0.76 [95% CI, 0.60-0.95]; P(trend) = .04), particularly advanced adenoma (OR, 0.48 [95% CI, 0.28-0.83]; P(trend) = .005). Among those with a previous adenoma detected through screening, aspirin use was associated with a decreased risk of advanced recurrent adenoma (≥30 vs \u3c4 pills per month: OR, 0.56 [95% CI, 0.36-0.87]; P(trend) = 0.006). Both aspirin (HR, 0.88 [95% CI, 0.81-0.96]; P(trend) \u3c.0001) and ibuprofen use (HR, 0.81 [95% CI, 0.70-0.93); P(trend) = 0.003) ≥30 versus \u3c4 pills per month were significantly associated with reduced CRC risk. CONCLUSIONS: In this large prospective study with long-term follow-up, a beneficial role for not only aspirin, but also ibuprofen, in preventing advanced adenoma and curbing progression to recurrence and cancer among older adults was observed

Improved Imputation of Common and Uncommon Single Nucleotide Polymorphisms (SNPs) with a New Reference Set

Statistical imputation of genotype data is an important technique for analysis of genome-wide association studies (GWAS). We have built a reference dataset to improve imputation accuracy for studies of individuals of primarily European descent using genotype data from the Hap1, Omni1, and Omni2.5 human SNP arrays (Illumina). Our dataset contains 2.5-3.1 million variants for 930 European, 157 Asian, and 162 African/African-American individuals. Imputation accuracy of European data from Hap660 or OmniExpress array content, measured by the proportion of variants imputed with R^2^>0.8, improved by 34%, 23% and 12% for variants with MAF of 3%, 5% and 10%, respectively, compared to imputation using publicly available data from 1,000 Genomes and International HapMap projects. The improved accuracy with the use of the new dataset could increase the power for GWAS by as much as 8% relative to genotyping all variants. This reference dataset is available to the scientific community through the NCBI dbGaP portal. Future versions will include additional genotype data as well as non-European populations

A Case-Control Study of Peripheral Blood Mitochondrial DNA Copy Number and Risk of Renal Cell Carcinoma

Background: Low mitochondrial DNA (mtDNA) copy number is a common feature of renal cell carcinoma (RCC), and may influence tumor development. Results: from a recent case-control study suggest that low mtDNA copy number in peripheral blood may be a marker for increased RCC risk. In an attempt to replicate that finding, we measured mtDNA copy number in peripheral blood DNA from a U.S. population-based case-control study of RCC. Methodology/Principal Findings: Relative mtDNA copy number was measured in triplicate by a quantitative real-time PCR assay using DNA extracted from peripheral whole blood. Cases (n = 603) had significantly lower mtDNA copy number than controls (n = 603; medians 0.85, 0.91 respectively; P = 0.0001). In multiple logistic regression analyses, the lowest quartile of mtDNA copy number was associated with a 60% increase in RCC risk relative to the highest quartile (OR = 1.6, 95% CI = 1.1–2.2; Ptrend = 0.009). This association remained in analyses restricted to cases treated by surgery alone (OR Q1 = 1.4, 95% CI = 1.0–2.1) and to localized tumors (2.0, 1.3–2.8). Conclusions/Significance: Our findings from this investigation, to our knowledge the largest of its kind, offer important confirmatory evidence that low mtDNA copy number is associated with increased RCC risk. Additional research is needed to assess whether the association is replicable in prospective studies

Steel Bridge Coating Evaluation and Rating Criteria

SPR-4632The aim of the study is to gather information on three topics: (1) the evaluation and rating of steel bridge protective coatings, (2) coating systems used by various states throughout the United States, and (3) maintenance painting procedures employed by various state department of transportation agencies (DOTs). First, it was found that most state DOTs use either an Element Level type rating of the coating system or a 9\u20130 NBI type rating; many state DOTs use both methodologies, with one used for state bridges and the other for local bridges. Second, for coating systems, it was found that there is a great deal of uniformity of the steel bridge coating systems used in the United States, with three-coat paint systems being the most common. Third, it is believed that maintenance painting can extend the useful life of bridge coatings. However, many state DOTs report that the cost of maintenance painting has increased due to many factors that involve available personnel, proper training, and increased regulations on the removal and application of steel bridge coatings. Consequently, many DOTs no longer perform maintenance painting, other than emergency repairs, and simply wait until the entire bridge needs to be re-coated and contract the work out. Lastly, an NBI 9\u20130 type rating procedure for steel bridge coatings is proposed for possible consideration and implementation by INDOT

Prediagnostic Serum Concentrations of Organochlorine Compounds and Risk of Testicular Germ Cell Tumors

BACKGROUND: Recent findings suggest that exposure to organochlorine (OC) compounds, chlordanes and p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) in particular, may increase the risk of developing testicular germ cell tumors (TGCTs). OBJECTIVE: To further investigate this question, we conducted a nested case-control study of TGCTs within the Norwegian Janus Serum Bank cohort. METHODS: The study was conducted among individuals with serum collected between 1972 and 1978. TGCT cases diagnosed through 1999 (n = 49; 27-62 years of age at diagnosis) were identified through linkage to the Norwegian Cancer Registry. Controls (n =51) were matched to cases on region, blood draw year, and age at blood draw. Measurements of 11 OC insecticide compounds and 34 polychlorinated biphenyl (PCB) congeners were performed using gas chromatography/high-resolution mass spectrometry. Case-control comparisons of lipid-adjusted analyte concentrations were performed using the Wilcoxon signed-rank test. Odds ratios (ORs) and 95% confidence intervals (CIs) for tertiles of analyte concentration were calculated using conditional logistic regression. RESULTS: TGCT cases had elevated concentrations of p,p′-DDE (tertile 3 vs. tertile 1 OR (ORT3) 2.2; 95% CI, 0.7-6.5; p Wilcoxon = 0.07), oxychlordane (ORT3 3.2; 95% CI, 0.6-16.8; pWilcoxon = 0.05), trans-nonachlor (ORT3 2.6; 95% CI, 0.7-8.9; pWilcoxon = 0.07), and total chlordanes (OR T3 2.0; 95% CI, 0.6-7.2; pWilcoxon = 0.048) compared with controls, although no ORs were statistically significant. Seminoma cases had significantly lower concentrations of PCB congeners 44, 49, and 52 and significantly higher concentrations of PCBs 99, 138, 153, 167, 183, and 195. CONCLUSIONS: Our study provides additional but qualified evidence supporting an association between exposures to p,p′-DDE and chlordane compounds, and possibly some PCB congeners, and TGCT risk

Racial difference in histologic subtype of renal cell carcinoma

In the United States, renal cell carcinoma (RCC) has rapidly increased in incidence for over two decades. The most common histologic subtypes of RCC, clear cell, papillary, and chromophobe have distinct genetic and clinical characteristics; however, epidemiologic features of these subtypes have not been well characterized, particularly regarding any associations between race, disease subtypes, and recent incidence trends. Using data from the Surveillance, Epidemiology, and End Results (SEER) Program, we examined differences in the age-adjusted incidence rates and trends of RCC subtypes, including analysis focusing on racial differences. Incidence rates increased over time (2001–2009) for all three subtypes. However, the proportion of white cases with clear cell histology was higher than among blacks (50% vs. 31%, respectively), whereas black cases were more likely than white cases to have papillary RCC (23% vs. 9%, respectively). Moreover, papillary RCC incidence increased more rapidly for blacks than whites (P < 0.01) over this period. We also observed that increased incidence of papillary histology among blacks is not limited to the smallest size strata. We observed racial differences in proportionate incidence of RCC subtypes, which appear to be increasing over time; this novel finding motivates further etiologic, clinical, molecular, and genetic studies