Microdissection of Shoot Meristem Functional Domains

The shoot apical meristem (SAM) maintains a pool of indeterminate cells within the SAM proper, while lateral organs are initiated from the SAM periphery. Laser microdissection–microarray technology was used to compare transcriptional profiles within these SAM domains to identify novel maize genes that function during leaf development. Nine hundred and sixty-two differentially expressed maize genes were detected; control genes known to be upregulated in the initiating leaf (P0/P1) or in the SAM proper verified the precision of the microdissections. Genes involved in cell division/growth, cell wall biosynthesis, chromatin remodeling, RNA binding, and translation are especially upregulated in initiating leaves, whereas genes functioning during protein fate and DNA repair are more abundant in the SAM proper. In situ hybridization analyses confirmed the expression patterns of six previously uncharacterized maize genes upregulated in the P0/P1. P0/P1-upregulated genes that were also shown to be downregulated in leaf-arrested shoots treated with an auxin transport inhibitor are especially implicated to function during early events in maize leaf initiation. Reverse genetic analyses of asceapen1 (asc1), a maize D4-cyclin gene upregulated in the P0/P1, revealed novel leaf phenotypes, less genetic redundancy, and expanded D4-CYCLIN function during maize shoot development as compared to Arabidopsis. These analyses generated a unique SAM domain-specific database that provides new insight into SAM function and a useful platform for reverse genetic analyses of shoot development in maize

Two Novel Susceptibility Loci for Prostate Cancer in Men of African Ancestry.

Prostate cancer incidence is 1.6-fold higher in African Americans than in other populations. The risk factors that drive this disparity are unknown and potentially consist of social, environmental, and genetic influences. To investigate the genetic basis of prostate cancer in men of African ancestry, we performed a genome-wide association meta-analysis using two-sided statistical tests in 10 202 case subjects and 10 810 control subjects. We identified novel signals on chromosomes 13q34 and 22q12, with the risk-associated alleles found only in men of African ancestry (13q34: rs75823044, risk allele frequency = 2.2%, odds ratio [OR] = 1.55, 95% confidence interval [CI] = 1.37 to 1.76, P = 6.10 × 10-12; 22q12.1: rs78554043, risk allele frequency = 1.5%, OR = 1.62, 95% CI = 1.39 to 1.89, P = 7.50 × 10-10). At 13q34, the signal is located 5' of the gene IRS2 and 3' of a long noncoding RNA, while at 22q12 the candidate functional allele is a missense variant in the CHEK2 gene. These findings provide further support for the role of ancestry-specific germline variation in contributing to population differences in prostate cancer risk

Suppression of *Verticillium dahliae* by glucosinolate-containing seed meal amendments

Neubauer C, Hüntemann K, Heitmann B, Müller C. Suppression of *Verticillium dahliae* by glucosinolate-containing seed meal amendments. European Journal of Plant Pathology. 2015;142(2):239-249.The biofumigation potential of glucosinolate (GSL)-containing seed meals to Verticillium dahliae was systematically evaluated. Cultivars of four different species of Brassicaceae were assessed using a standardized bioassay with microsclerotia-infested sterile quartz sand amended with defatted seed meals at a rate of 0.4 % (vol/vol). Additionally, the GSL profile and isothiocyanate (ITC) release of the meals were determined. Brassica napus and Sinapis alba seed meals failed to reduce the number of viable microsclerotia significantly due to low concentrations and/or toxicity of the ITCs released. Amendments with B. juncea and B. carinata seed meals eliminated all microsclerotia in the sterile sand. The meals had 2-propenyl GSL concentrations between 82.8 and 108.1 mu mol g(-1). ITC release efficiencies ranged between 62.5 and 100 %. The expected amounts of 2-propenyl ITC released by the amendments suggest that the elimination of microsclerotia by the sinigrin-containing seed meals was predominantly an ITC-related effect. But in natural infested soils the efficiencies of B. juncea seed meal amendments were reduced. Depending on soil characteristics practical meal amendment rates of 4.0 t ha(-1) or higher may be necessary to achieve sufficient Verticillium control. Additionally, the temporal pattern of ITC release of the amended B. juncea seed meal in two natural soils compared to sterile sand was determined. Maximum ITC concentrations were measured between 3 and 6 h after application, before concentrations decreased continuously and reached a minimum after 48 h. In summary, the findings suggest that sinigrin-containing seed meal amendments can be a useful tool in the management of Verticillium, especially on sandy soils with low organic carbon contents

Risk Factors for Serrated Polyps of the Colorectum

Serrated pathway polyps are a relatively new area of interest in the field of colorectal cancer screening and prevention. Akin to conventional adenomas, some serrated polyps (SPs) have the potential to develop into malignant serrated neoplasms, yet little is known regarding risk factors for these lesions. Early epidemiological studies of hyperplastic polyps (HPs) were performed without knowledge of the serrated pathway, and likely included a mixture of SPs. More recently, studies have specifically evaluated premalignant SPs, such as the sessile serrated adenoma (SSA) or surrogates for these polyps such as large or proximally-located SPs. SPs share some risk factors with conventional adenomas, and have been associated with tobacco use, obesity, and age. Nonsteroidal anti-inflammatory drug (NSAID) use, fiber, folic acid, and calcium have been associated with reduced risk of SPs. Studies focused on SSAs specifically have reported associations with age, female sex, smoking, obesity, diabetes, and possibly diets high in fat, carbohydrates, and calories. Higher education has also been associated with risk of SSAs, while an inverse association between NSAID use and SSAs has been reported. Risk factors for traditional serrated adenomas (TSAs) are largely unknown. Studies are largely limited by varying inclusion criteria, as well as differences in pathological classification schemes. Further epidemiological studies of SPs are needed to aid in risk stratification and screening, and etiological research