Genome-Wide Investigation of Multifocal and Unifocal Prostate Cancer—Are They Genetically Different?

Prostate cancer is widely observed to be biologically heterogeneous. Its heterogeneity is manifested histologically as multifocal prostate cancer, which is observed more frequently than unifocal prostate cancer. The clinical and prognostic significance of either focal cancer type is not fully established. To investigate prostate cancer heterogeneity, the genetic profiles of multifocal and unifocal prostate cancers were compared. Here, we report observations deduced from tumor-tumor comparison of copy number alteration data of both focal categories. Forty-one fresh frozen prostate cancer foci from 14 multifocal prostate cancers and eight unifocal prostate cancers were subjected to copy number variation analysis with the Affymetrix SNP 6.0 microarray tool. With the investigated cases, tumors obtained from a single prostate exhibited different genetic profiles of variable degrees. Further comparison identified no distinct genetic pattern or signatures specific to multifocal or unifocal prostate cancer. Our findings suggest that samples obtained from multiple sites of a single unifocal prostate cancer show as much genetic heterogeneity and variability as separate tumors obtained from a single multifocal prostate cancer.     

In-house validation of a simplified method for the determination of PCBs in food and feedingstuffs

This paper comprises a simplified method for the determination of polychlorinated biphenyls (PCBs) in food and feedingstuffs. The method includes a cold column extraction step, a simple clean-up with concentrated sulfuric acid, and a final determination of the PCBs using gas chromatography-mass spectrometry (GC/MS). An in-house validation study was performed to establish method performance characteristics such as decision limit, detection capability, trueness and precision of the method. To determine these characteristics both certified reference materials and spiked samples were utilized. The decision limit and the detection capability of the individual PCB congeners in food were 2 ng/g and 3 ng/g fat, respectively, while corresponding figures for feedingstuffs were 7 ng/g and 9 ng/g fat, respectively. The coefficient of variation (CV) varied from 2% to 5% for food on the 10 ng/g fat level and from 2% to 6% for feedingstuffs on the 25 ng/g fat level. The recoveries of the individual PCB congeners varied from 88% to 107%, indicating good correspondence with internationally recognized criteria for the performance characteristics of analytical methods. The robustness of the method was investigated by employing a factorial design methodology to determine the influence of six experimental factors on the results of the analysis. This clearly demonstrated that the method is fit for surveillance of PCBs in food and feedingstuffs, even though some care has to be taken with the solvent volume during the cold column extraction step as well as the addition of the standard to the sample. Additionally, the investigation clearly demonstrates that in-house validation approaches may be used for determination of the overall performance of analytical methods.     

Effect of roasting on the radical scavenging activity of cocoa beans

The free-radical scavenging activity of cocoa samples subjected to different roasting treatments has been determined. The samples (raw, pre-roasted and roasted) were separated into four molecular weight fractions per sample (>30, 30–10, 10–5, and <5 kDa). The free-radical scavenging activity was determined with the DPPH^• (1,1-dipheny-2-picrylhydrazyl), and ABTS^•+ [2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)] free-radical scavenging assays for all samples. Both tests were compared in terms of sensitivity and measurement precision, at different reaction times. Comparing the results from each test, the free-radical scavenging activity trends were similar for each fraction but with notable differences in the sensitivity of the assays. Analysis of the concentration of reducing substances, such as water soluble phenolics, melanoidins, carbohydrates, etc, in these fractions by the photometric Folin–Ciocalteu assay, showed a similar pattern to the free-radical scavenging activity trend. Moreover, this comparison showed that there were significantly (P < 0.05) more reducing substances and free-radical scavenging activity in the 10–5 kDa roasted cocoa bean fraction.     

Comparison of two quantitative proton density mapping methods in multiple sclerosis

Objective

Proton density (PD) mapping requires correction for the receive profile (RP), which is frequently performed via bias-field correction. An alternative RP-mapping method utilizes a comparison of uncorrected PD-maps and a value ρ(T1) directly derived from T1-maps via the Fatouros equation. This may be problematic in multiple sclerosis (MS), if respective parameters are only valid for healthy brain tissue. We aimed to investigate whether the alternative method yields correct PD values in MS patients.

Materials/methods

PD mapping was performed on 27 patients with relapsing-remitting MS and 27 healthy controls, utilizing both methods, yielding reference PD values (PD_ref, bias-field method) and PD_alt (alternative method).

Results

PD_alt-values closely matched PD_ref, both for patients and controls. In contrast, ρ(T1) differed by up to 3 % from PD_ref, and the voxel-wise correlation between PD_ref and ρ(T1) was reduced in a patient subgroup with a higher degree of disability. Still, discrepancies between ρ(T1) and PD_ref were almost identical across different tissue types, thus translating into a scaling factor, which cancelled out during normalization to 100 % in CSF, yielding a good agreement between PD_alt and PD_ref.

Conclusion

RP correction utilizing the auxiliary parameter ρ(T1) derived via the Fatouros equation provides accurate PD results in MS patients, in spite of discrepancies between ρ(T1) and actual PD values.

     

Latent risk and trend models for the evolution of annual fatality numbers in 30 European countries

In this paper a unified methodology is presented for the modelling of the evolution of road safety in 30 European countries. For each country, annual data of the best available exposure indicator and of the number of fatalities were simultaneously analysed with the bivariate latent risk time series model. This model is based on the assumption that the amount of exposure and the number of fatalities are intrinsically related. It captures the dynamic evolution in the fatalities as the product of the dynamic evolution in two latent trends: the trend in the fatality risk and the trend in the exposure to that risk. Before applying the latent risk model to the different countries it was first investigated and tested whether the exposure indicator at hand and the fatalities in each country were in fact related at all. If they were, the latent risk model was applied to that country; if not, a univariate local linear trend model was applied to the fatalities series only, unless the latent risk time series model was found to yield better forecasts than the univariate local linear trend model. In either case, the temporal structure of the unobserved components of the optimal model was established, and structural breaks in the trends related to external events were identified and captured by adding intervention variables to the appropriate components of the model. As a final step, for each country the optimally modelled developments were projected into the future, thus yielding forecasts for the number of fatalities up to and including 2020.     

Heme-dependent and heme-independent nitrite reduction by lactic acid bacteria results in different N-containing products

Seventy strains of lactic acid bacteria were investigated for nitrite reductase activity. Two types of this activity were detected. Type I was found in Lactobacillus plantarum, L. pentosus and Pediococcus pentosaceus. This activity is heme-dependent with ammonia as the sole product. Type II mechanism is heme-independent and reduces nitrite to NO and N₂O.     

Sourdough in gluten-free bread-making: An ancient technology to solve a novel issue?

The increasing demand for high quality gluten-free (GF) bread, clean labels and natural products is raising the need for new approaches in GF bread-making. Sourdough is the foremost fermentation used for baking purposes and it has been proven to be ideal for improving the texture, palatability, aroma, shelf life and nutritional value of wheat and rye breads. These characteristic features derive from the complex metabolic activities of the sourdough-resident lactic acid bacteria and yeasts, e.g. acidification, production of exopolysaccharides, proteolytic- amylolytic- and phytase activity, and production of antimicrobial substances. These effects have been extensively studied and well described for traditional baking, whereas little is known about the role of sourdough in GF baking. Yet, the microbiological and qualitative characterisation of local GF fermented products indicate an overlap with the microbiota of wheat/rye fermentation and suggest that the positive metabolic activities of the sourdough microbiota are still retained during fermentation of GF crops. Thus, the use of sourdough in GF baking may be the new frontier for improving the quality, safety and acceptability of GF bread.     

A fundamental prediction error: Self–others discrepancies in risk preference.

This research examined whether people can accurately predict the risk preferences of others. Three experiments featuring different designs revealed a systematic bias: that participants predicted others to be more risk seeking than themselves in risky choices, regardless of whether the choices were between options with negative outcomes or with positive outcomes. This self–others discrepancy persisted even if a monetary incentive was offered for accurate prediction. However, this discrepancy occurred only if the target of prediction was abstract and vanished if the target was vivid. A risk-as-feelings hypothesis was introduced to explain these findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Study of human isoursodeoxycholic acid metabolism

BACKGROUND/AIMS: The aim of this study was to examine the metabolism of isoursodeoxycholic acid (isoUDCA) in humans. METHODS: IsoUDCA was synthesized of >99% purity and administered orally for 1 week, 3 x 250 mg/day, to six healthy male subjects. Bile acids were extracted from duodenal bile, serum, and 24-h urine samples collected before and at the end of the study period, separated into groups of conjugates, and analyzed by gas chromatography-mass spectrometry and fast atom bombardment mass spectrometry. RESULTS: IsoUDCA was tolerated without any side effect. Liver function tests did not change. Bile acid concentrations (mean+/-SEM) increased from 11.9+/-1.87 to 15.3+/-1.37 mmol/l in bile (n.s.), and from 3.4+/-0.10 to 6.8+/-0.43 micromol/l in serum (p<0.05). Urinary excretion of bile acids increased from 5.3+/-0.29 to 82.2+/-7.84 micromol/24 h (p<0.01). All changes were due to significant increases of isoUDCA and UDCA in bile, serum and urine, and of 3-dehydro-UDCA, the 3-oxo intermediate of isomerization, in bile and in serum. The relative enrichments of isoUDCA, UDCA, and 3-dehydro-UDCA, were: in bile, 2.2%, 25.7%, and 0.7%; in serum, 24.7%, 23.5%, and 6.1%; and in urine, 83.7%, 2.0%, and 2.4%. Whereas 78% of serum isoUDCA was unconjugated, 93-94% of biliary and urinary isoUDCA was conjugated with N-acetylglucosamine. CONCLUSIONS: This study indicates good tolerance and significant intestinal absorption of orally administered isoUDCA. IsoUDCA is extensively isomerized, probably both by intestinal and hepatic enzymes to yield UDCA which became the major biliary compound. In vitro, using the human hepatoblastoma cell line Hep G2, isoUDCA was found to be cytoprotective towards ethanol-induced cell injuries.