The effect of imaging modality (magnetic resonance imaging vs. computed tomography) and patient position (supine vs. prone) on target and organ at risk doses in partial breast irradiation.

INTRODUCTION: Conventionally computed tomography (CT) has been used to delineate target volumes in radiotherapy; however, magnetic resonance imaging (MRI) is being continually integrated into clinical practice; therefore, the investigation into targets derived from MRI is warranted. The purpose of this study was to evaluate the impact of imaging modality (MRI vs. CT) and patient positioning (supine vs. prone) on planning target volumes (PTVs) and organs at risk (OARs) for partial breast irradiation (PBI). METHODS: A retrospective data set, of 35 patients, was accessed where each patient had undergone MRI and CT imaging for tangential whole breast radiotherapy in both the supine and prone position. PTVs were defined from seroma cavity (SC) volumes delineated on each respective image, resulting in 4 PTVs per patient. PBI plans were generated with 6MV external beam radiotherapy (EBRT) using the TROG 06.02 protocol guidelines. A prescription of 38.5Gy in 10 fractions was used for all cases. The impact analysis of imaging modality and patient positioning included dose to PTVs, and OARs based on agreed criteria. Statistical analysis was conducted though Mann-Whitey U, Fisher's exact and chi-squared testing (P < 0.005). RESULTS: Twenty-four patients were eligible for imaging analysis. However, positioning analysis could only be investigated on 19 of these data sets. No statistically significant difference was found in OAR doses based on imaging modality. Supine patient position resulted in lower contralateral breast dose (0.10Gy ± 0.35 vs. 0.33Gy ± 0.78, p = 0.011). Prone positioning resulted in a lower dose to ipsilateral lung volumes (10.85Gy ± 11.37 vs. 3.41Gy ± 3.93, P = <0.001). CONCLUSIONS: PBI plans with PTVs derived from MRI exhibited no clinically significant differences when compared to plans created from CT in relation to plan compliance and OAR dose. Patient position requires careful consideration regardless of imaging modality chosen. Although there was no proven superiority of MRI derived target volumes, it indicates that MRI could be considered for PBI target delineation.

Complete Genome Sequences of Two Salmonella enterica subsp. enterica Serovar Anatum Strains Isolated from Papaya.

Salmonella enterica is a major global foodborne pathogen that causes gastroenteritis and, in some cases, death. Salmonella serovar Anatum has been increasingly associated with foodborne salmonellosis outbreaks. In this report, we announce two complete genome sequences of Salmonella Anatum isolated from papaya fruit.

Microbiota of the Hickey Run Tributary of the Anacostia River.

Water from the Hickey Run Tributary of the Anacostia River is being collected quarterly (beginning August 2018) and analyzed to create high-resolution baseline taxonomic profiles of microbiota associated with this important aquatic ecosystem, which has a long history of exposure to residential and commercial effluents from Washington, DC. These United States National Arboretum Microbial Observatory data are available under NCBI BioProject number PRJNA498951.

Draft Genome Sequences of 57 Salmonella enterica Strains from Selected U.S. Swine Feed Mills.

The number of Salmonella infection cases linked to pork products has increased. Pathogen presence in the feed mill environment is one of the many potential transmission routes into the food production chain. Here, we describe the draft genome sequences of 57 Salmonella enterica isolates from selected U.S. swine feed mills.

Draft Genome Sequences of 112 Salmonella enterica Serovar Dublin Strains Isolated from Humans and Animals in Brazil.

Salmonella enterica serovar Dublin is a strongly adapted serovar that causes enteritis and/or systemic disease in cattle and results in high rates of mortality. Here, we report the draft genome sequences of 112 S. Dublin strains isolated from humans and animals in Brazil. These draft genome sequences will help enhance our understanding of this serovar in Brazil.

Quantitative Trait Loci Mapping for Spike Characteristics in Hexaploid Wheat.

Wheat ( L.) spike characteristics determine the number of grains produced on each spike and constitute key components of grain yield. Understanding of the genetic basis of spike characteristics in wheat, however, is limited. In this study, genotyping-by-sequencing (GBS) and the iSelect 9K assay were used on a doubled-haploid (DH) soft red winter wheat population that showed a wide range of phenotypic variation for spike traits. A genetic map spanning 2934.1 cM with an average interval length of 3.4 cM was constructed. Quantitative trait loci (QTL) analysis involving additive effects, epistasis (QQ) and QTL × environment (QE), and epistasis × environment (QQE) interactions detected a total of 109 QTL, 13 QE, and 20 QQ interactions in five environments. Spike characteristics were mainly determined by additive effects and were fine-tuned by QQ, QE, and QQE. Major QTL / explained up to 30.9% of the phenotypic variation for spike length (SL) and fertile spikelet number, .1 explained up to 15.6% of the phenotypic variation of grain number per spikelet, and explained up to 80.2% of the phenotypic variation for spike compactness. Additionally, QTL for correlated spike characteristics formed QTL clusters on chromosomes 1A, 5A, 2B, 3B, 5B, 1D, and 5D. This study expands the understanding of the genetic basis of spike characteristics in hexaploid wheat. A number of stable QTL detected in this study have potential to be used in marker-assisted selection. Additionally, the genetic map generated in this study could be used to study other traits of economic importance.