Evaluation of intake fractions for different subpopulations due to primary fine particulate matter (PM2.5) emitted from domestic wood combustion and traffic in Finland

Domestic wood combustion and traffic are the two most significant primary fine particulate matter (PM_2.5) emission source categories in Finland. We estimated emission–exposure relationships for primary PM_2.5 emissions from these source categories using intake fractions (iF), which describes the fraction of an emission that is ultimately inhaled by a target population. The iFs were calculated for four different emission source subcategories in Finland in 2000: (1) domestic wood combustion in residential buildings, (2) domestic wood combustion in recreational buildings, (3) traffic exhaust and wear emissions, and (4) traffic resuspension emissions. The iFs were estimated for both total population and for subpopulations with different gender, age, and educational status. Primary PM_2.5 emissions were based on the Finnish Regional Emission Scenario model and the dispersion of particles was calculated using the Urban Dispersion Modeling system of Finnish Meteorological Institute. Both emissions and dispersion were estimated on a 1 km spatial resolution. The iFs for primary PM_2.5 emissions from (1) residential and (2) recreational buildings were 3.4 and 0.6 per million, respectively. The corresponding iF for (3) traffic exhaust and wear and (4) traffic resuspension emissions were 9.7 and 9.5 per million, respectively. The differences in population-weighted outdoor concentrations were significant between subpopulations with different educational status so that people with higher education were exposed more to traffic-related PM_2.5.     

Amplification of epidermal growth factor receptor gene in renal cell carcinoma

Expression of epidermal growth factor receptor (EGFR) may be of prognostic value in renal cell cancer (RCC). Gene amplification of EGFR was investigated in a cohort of 315 patients with advanced RCC from a previously reported randomised study. Using fluorescent in situ hybridisation, only 2 patients (0.6%) had gene amplification; therefore gene amplification is of no prognostic value in RCC.     

Characteristics Associated With Parent–Teacher Concordance on Child Behavior Problem Ratings in Low-Income Preschoolers

Objective

Assessment of pediatric behavior problems often requires rating scales from multiple reporters in different settings (eg, home and school); however, concordance between reporters may be low. Pediatricians must reconcile differences to inform treatment. We sought to examine characteristics predicting parent–teacher concordance on ratings of preschoolers' behavior problems.

The influence of genetic polymorphisms of GSTP1 on the development of asbestosis

OBJECTIVE: Genetic factors play an important role in the development of asbestosis. The aim of this study was to investigate whether genetic polymorphisms of glutathione S-transferase (GST) P1 represent a risk factor for this disease. METHODS: The study population included 262 workers with asbestosis and 265 matched controls. Information on cumulative asbestos exposure was available. A real-time PCR based on the 5' nuclease assay was designed for the analysis of GSTP1 Ile105Val and Ala114Val polymorphisms. RESULTS: Asbestosis was associated with GSTP1 genotype coding for an enzyme with high conjugation capacity versus genotypes resulting in intermediate and low enzyme activity (odds ratio = 1.49, confidence interval = 1.06-2.10). CONCLUSIONS: The key finding of the study was that GSTP1 genotype coding for an enzyme with high conjugation capacity significantly increases the risk of developing asbestosis.     

Comparison of composite prostate radiotherapy plan doses with dependent and independent boost phases

Prostate cases commonly consist of dual phase planning with a primary plan followed by a boost. Traditionally, the boost phase is planned independently from the primary plan with the risk of generating hot or cold spots in the composite plan. Alternatively, boost phase can be planned taking into account the primary dose. The aim of this study was to compare the composite plans from independently and dependently planned boosts using dosimetric and radiobiological metrics. Ten consecutive prostate patients previously treated at our institution were used to conduct this study on the Raystation? 4.0 treatment planning system. For each patient, two composite plans were developed: a primary plan with an independently planned boost and a primary plan with a dependently planned boost phase. The primary plan was prescribed to 54 Gy in 30 fractions to the primary planning target volume (PTV1) which includes prostate and seminal vesicles, while the boost phases were prescribed to 24 Gy in 12 fractions to the boost planning target volume (PTV2) that targets only the prostate. PTV coverage, max dose, median dose, target conformity, dose homogeneity, dose to OARs, and probabilities of benefit, injury, and complication-free tumor control (P₊) were compared. Statistical significance was tested using either a 2-tailed Student’s t-test or Wilcoxon signed-rank test. Dosimetrically, the composite plan with dependent boost phase exhibited smaller hotspots, lower maximum dose to the target without any significant change to normal tissue dose. Radiobiologically, for all but one patient, the percent difference in the P₊ values between the two methods was not significant. A large percent difference in P₊ value could be attributed to an inferior primary plan. The benefits of considering the dose in primary plan while planning the boost is not significant unless a poor primary plan was achieved.     

Construction of oncogenetic tree models reveals multiple pathways of oral cancer progression

Oral cancer develops and progresses by accumulation of genetic alterations. The interrelationship between these alterations and their sequence of occurrence in oral cancers has not been thoroughly understood. In the present study, we applied oncogenetic tree models to comparative genomic hybridization (CGH) data of 97 primary oral cancers to identify pathways of progression. CGH revealed the most frequent gains on chromosomes 8q (72.4%) and 9q (41.2%) and frequent losses on 3p (49.5%) and 8p (47.5%). Both mixture and distance‐based tree models suggested multiple progression pathways and identified +8q as an early event. The mixture model suggested two independent pathways namely a major pathway with ?8p and a less frequent pathway with +9q. The distance‐based tree identified three progression pathways, one characterized by ?8p, another by ?3p and the third by alterations +11q and +7p. Differences were observed in cytogenetic pathways of node‐positive and node‐negative oral cancers. Node‐positive cancers were characterized by more non‐random aberrations (n = 11) and progressed via ?8p or ?3p. On the other hand, node‐negative cancers involved fewer non‐random alterations (n = 6) and progressed along ?3p. In summary, the tree models for oral cancers provided novel information about the interactions between genetic alterations and predicted their probable order of occurrence. © 2009 UICC