Different methods for contouring target volumes are currently in use in the UK when irradiating glioblastomas post operatively. Both one- and two-phase techniques are offered at different centres. ...90% of relapses are recognised to occur locally when using radiotherapy alone. The objective of this evaluation was to determine the pattern of relapse following concomitant radiotherapy with temozolomide (RT-TMZ).
A retrospective analysis of patients receiving RT-TMZ between 2006 and 2010 was performed. Outcome data including survival were calculated from the start of radiotherapy. Analysis of available serial cross-sectional imaging was performed from diagnosis to first relapse. The site of first relapse was defined by the relationship to primary disease. Central relapse was defined as progression of the primary enhancing mass or the appearance of a new enhancing nodule within 2 cm.
105 patients were identified as receiving RT-TMZ. 34 patients were not eligible for relapse analysis owing to either lack of progression or unsuitable imaging. Patterns of first relapse were as follows: 55 (77%) patients relapsed centrally within 2 cm of the original gadolinium-enhanced mass on MRI, 13 (18%) patients relapsed >4 cm from the original enhancement and 3 (4%) relapsed within the contralateral hemisphere.
Central relapse remains the predominant pattern of failure following RT-TMZ. Single-phase conformal radiotherapy using a 2-cm margin from the original contrast-enhanced mass is appropriate for the majority of these patients.
Central relapse remains the predominant pattern of failure following chemoradiotherapy for glioblastomas.
Characterization of nearly 1,000 cultivated potato accessions with simple sequence repeats (SSRs; also referred to as microsatellites) has allowed the identification of a reference set of SSR markers ...for accurate and efficient genotyping. In addition, 31 SSRs are reported here for a potato genetic map, including new map locations for 24 of them. A first criterion for this proposed reference set was ubiquity of the SSRs in the eight landrace cultivar groups of the potato, Solanum tuberosum. All SSRs tested in the present study displayed the same allele phenotypes and allele size range in the diverse germplasm set as in the advanced potato cultivar germplasm in which they were originally discovered. Thirteen of 13 SSR products from all cultivar groups are shown to cross-hybridize with the corresponding SSR product of the source cultivar to ascertain sequence homology. Other important SSR selection criteria are quality of amplification products, locus complexity, polymorphic index content, and well-dispersed location on a potato genetic map. Screening of 156 SSRs allowed the identification of a highly informative and user-friendly set comprising 18 SSR markers for use in characterization of potato genetic resources. In addition, we have identified true- and pseudo-multiplexing SSRs for even greater efficiency.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Solanum tuberosum L. Phureja Group consists of potato landraces widely grown in the Andes from western Venezuela to central Bolivia, and forms an important breeding stock due to their excellent ...culinary properties and other traits for developing modern varieties. They have been distinguished by short-day adaptation, diploid ploidy (2n = 2x = 24), and lack of tuber dormancy. This nuclear simple sequence repeat (nSSR or microsatellite) study complements a prior random amplified polymorphic DNA (RAPD) study to explore the use of these markers to form a core collection of cultivar groups of potatoes. Like this prior RAPD study, we analyzed 128 accessions of the Phureja Group using nuclear microsatellites (nSSR). Twenty-six of the 128 accessions were invariant for 22 nSSR markers assayed. The nSSR data uncovered 25 unexpected triploid and tetraploid accessions. Chromosome counts of the 102 accessions confirmed these nSSR results and highlighted seven more triploids or tetraploids. Thus, these nSSR markers (except 1) are good indicators of ploidy for diploid potatoes in 92% of the cases. The nSSR and RAPD results: (1) were highly discordant for the remaining 70 accessions that were diploid and variable in nSSR, (2) show the utility of nSSRs to effectively uncover many ploidy variants in cultivated potato, (3) support the use of a cultivar-group (rather than a species) classification of cultivated potato, (4) fail to support a relationship between genetic distance and geographic distance, (5) question the use of any single type of molecular marker to construct core collections.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Previous work on Bartram's round-winged katydid, Amblycorypha bartrami Walker, found inconsistencies in song variation across the species' range. Individuals of purported populations of A. bartrami ...from sandhills across the southeastern US were collected, recorded, and their genes were sequenced to better understand their population structure and evolution. Significant differences in songs, morphology, and genetics were found among populations from Alabama (AL), Georgia (GA), North Carolina (NC), and South Carolina (SC), and they differed from those of individuals collected from the type locality in Florida (FL). Males from all populations produced songs composed of a series of similar syllables, but they differed in the rates at which syllables were produced as a function of temperature. At temperatures of 25°C, the calling songs of males from populations in northern AL and GA were found to have the highest syllable rates, those from SC had the lowest rates, and those from NC were found to produce songs with doublet syllables at rates that were intermediate between those of males from FL and those of AL and GA. These song differences formed the basis for cluster analyses and principal component analyses, which showed significant clustering and differences in song spectra and morphology among the song morphs. A Bayesian multi-locus, multi-species coalescent analysis found significant divergences from a panmictic population for the song morphs. Populations from GA and AL are closely related to those of A. bartrami in FL, whereas populations from NC and SC are closely related to each other and differ from the other three. Large river systems may have been important in isolating these populations of flightless katydids. Based on the results of our analyses of songs, morphology, and genetics, three new species of round-winged katydids from the southeastern coastal plain and piedmont are described.
The use of cytotoxic chemotherapy in both advanced and early stage breast cancer has made significant progress in the last 10 years with several landmark studies identifying clear survival benefits ...for newer therapies. In spite of these developments the optimal approach for any specific patient can not be determined from a literature review or decision-making algorithm alone. Treatment choices are predominantly based on practice determined by individual or collective experience and the historical development of treatment within a locality. The improvement in the understanding of the molecular biological basis of breast cancer provides possible targets for novel therapies. Personalised therapies for breast cancer based on the molecular characteristics of the tumour could improve the risk: benefit ratio of current therapies. Increased improvements in the use of a panel of biomarkers will thus not only move us towards tailored therapies but will also spare a group of patients that do not benefit from adjuvant chemotherapy. At the same time a better understanding of tumour biology will also streamline the development of new regimens for those who are unlikely to benefit from existing drugs. This review will focus on the evidence for the use of chemotherapy and highlight advances in chemotherapy treatments with the addition of new and novel drugs marching into our clinics as standard treatments based on evidence from clinical trials and from a better understanding of tumour biology that has transformed the outlook in breast cancer in both the adjuvant and metastatic setting.
Potato late blight, caused by the oomycete phytopathogen Phytophthora infestans, is a devastating disease found in potato-growing regions worldwide. Long-term management strategies to control late ...blight include the incorporation of host resistance to predominant strains. However, due to rapid genetic changes within pathogen populations, rapid and recurring identification and integration of novel host resistance traits is necessary. Wild relatives of potato offer a rich source of desirable traits, including late blight resistance, but screening methods can be time intensive. We tested the ability of taxonomy, ploidy, crossing group, breeding system, and geography to predict the presence of foliar and tuber late blight resistance in wild Solanum spp. Significant variation for resistance to both tuber and foliar late blight was found within and among species but there was no discernable predictive power based on taxonomic series, clade, ploidy, breeding system, elevation, or geographic location. We observed a moderate but significant correlation between tuber and foliar resistance within species. Although previously uncharacterized sources of both foliar and tuber resistance were identified, our study does not support an assumption that taxonomic or geographic data can be used to predict sources of late blight resistance in wild Solanum spp.
We describe algorithmic enhancements to a decision-support tool that residential consumers can utilize to optimize their acquisition of electrical energy services. The decision-support tool optimizes ...energy services provision by enabling end users to first assign values to desired energy services, and then scheduling their available distributed energy resources (DER) to maximize net benefits. We chose particle swarm optimization (PSO) to solve the corresponding optimization problem because of its straightforward implementation and demonstrated ability to generate near-optimal schedules within manageable computation times. We improve the basic formulation of cooperative PSO by introducing stochastic repulsion among the particles. The improved DER schedules are then used to investigate the potential consumer value added by coordinated DER scheduling. This is computed by comparing the end-user costs obtained with the enhanced algorithm simultaneously scheduling all DER, against the costs when each DER schedule is solved separately. This comparison enables the end users to determine whether their mix of energy service needs, available DER and electricity tariff arrangements might warrant solving the more complex coordinated scheduling problem, or instead, decomposing the problem into multiple simpler optimizations.
A major justification for taxonomic research is its assumed ability to predict the presence of traits in a group for which the trait has been observed in a representative subset of the group. ...Similarly, populations in similar environments are expected to be more alike than populations in divergent environments. Consequently, it is logical to assume that taxonomic relationships and biogeographical data have the power to predict the distribution of disease resistance phenotypes among plant species. The objective of this study was to test predictivity in a group of widely distributed wild potato species, based on hypotheses that closely related organisms (taxonomy) or organisms from similar environments (biogeography) share resistance to a simply inherited trait (Potato virus Y PVY). We found that wild potato species with an endosperm balance number (EBN) of 1 (a measure of cross compatibility) shared resistances to PVY more than species with different EBN values. However, a large amount of variation was found for resistance to PVY among and within species. We also found that populations from low elevations were more resistant than those from high elevations. Because PVY is vectored by aphids, we speculate that the distribution of aphids may determine the level of selection pressure for PVY resistance.
Interruptible loads represent highly valuable demand side resources within the electricity industry. However, maximizing their potential value in terms of system security and scheduling is a ...considerable challenge because of their widely varying and potentially complex operational characteristics. This paper investigates the use of binary particle swarm optimization (BPSO) to schedule a significant number of varied interruptible loads over 16 h. The scheduling objective is to achieve a system requirement of total hourly curtailments while satisfying the operational constraints of the available interruptible loads, minimizing the total payment to them and minimizing the frequency of interruptions imposed upon them. This multiobjective optimization problem was simplified by using a single aggregate objective function. The BPSO algorithm proved capable of achieving near-optimal solutions in manageable computational time-frames for this relatively complex, nonlinear and noncontinuous problem. The effectiveness of the approach was further improved by dividing the swarm into several subswarms. The proposed scheduling technique demonstrated useful performance for a relatively challenging scheduling task, and would seem to offer some potential advantages in scheduling significant numbers of widely varied and technically complex interruptible loads.
The role of adjuvant treatment in pancreatic cancer remains uncertain. The European Study Group for Pancreatic Cancer (ESPAC) assessed the roles of chemoradiotherapy and chemotherapy in a randomised ...study.
After resection, patients were randomly assigned to adjuvant chemoradiotherapy (20 Gy in ten daily fractions over 2 weeks with 500 mg/m2 fluorouracil intravenously on days 1–3, repeated after 2 weeks) or chemotherapy (intravenous fluorouracil 425 mg/m2 and folinic acid 20 mg/m2 daily for 5 days, monthly for 6 months). Clinicians could randomise patients into a two-by-two factorial design (observation, chemoradiotherapy alone, chemotherapy alone, or both) or into one of the main treatment comparisons (chemoradiotherapy versus no chemoradiotherapy or chemotherapy versus no chemotherapy). The primary endpoint was death, and all analyses were by intention to treat.
541 eligible patients with pancreatic ductal adenocarcinoma were randomised: 285 in the two-by-two factorial design (70 chemoradiotherapy, 74 chemotherapy, 72 both, 69 observation); a further 68 patients were randomly assigned chemoradiotherapy or no chemoradiotherapy and 188 chemotherapy or no chemotherapy. Median follow-up of the 227 (42%) patients still alive was 10 months (range 0–62). Overall results showed no benefit for adjuvant chemoradiotherapy (median survival 15·5 months in 175 patients with chemoradiotherapy vs 16·1 months in 178 patients without; hazard ratio 1·18 95% Cl 0·90–1·55, p=0·24). There was evidence of a survival benefit for adjuvant chemotherapy (median survival 19·7 months in 238 patients with chemotherapy vs 14·0 months in 235 patients without; hazard ratio 0·66 0·52–0·83, p=0·0005).
This study showed no survival benefit for adjuvant chemoradiotherapy but revealed a potential benefit for adjuvant chemotherapy, justifying further randomised controlled trials of adjuvant chemotherapy in pancreatic cancer.
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DOBA, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SIK, UILJ, UKNU, UL, UM, UPCLJ, UPUK, VSZLJ
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