Two choice studies were performed to evaluate greenbug, Schizaphis graminum (Rondani), and yellow sugarcane aphid, Sipha flava (Forbes), preference for two tetraploid switchgrass populations, Summer ...and Kanlow, and one experimental hybrid, K × S, derived by crossing Kanlow (male) × Summer (female) plants. Additionally, an assessment of S. graminum feeding behavior was performed on the same switchgrass populations, by using the electrical penetration graph (EPG) technique. Choice studies for S. flava indicated a lack of antixenosis, with no preference by aphids among any of the switchgrass populations at any time point. However, choice studies with S. graminum indicated a preference for the K × S plants at 24 h after aphid introduction. No obvious differences were observed for the leaf surfaces between the three populations. Feeding behavior studies for S. graminum on switchgrasses indicated no differences for the time to first probe or time to first sieve element phase among switchgrass populations. However, duration of sieve element phases for S. graminum was significantly less on Kanlow compared to K × S and Summer. S. graminum also had a significantly lower potential phloem ingestion index (PPII) and few aphids showing sustained phloem ingestion on Kanlow as compared to K × S and Summer plants. These results suggest that resistance factors (chemical or mechanical) in Kanlow are located in the phloem tissue. At the whole leaf level, some differences were observed for a subset of polar metabolites, although Kanlow plants were significantly enriched for oxalic acid.
Abstract
Background
An upstream approach to palliative care in the last 12 months of life delivered by primary care practices is often referred to as Primary Palliative Care (PPC). Implementing case ...management functions can support delivery of PPC and help patients and their families navigate health, social and fiscal environments that become more complex at end-of-life. A realist synthesis was conducted to understand how multi-level contexts affect case management functions related to initiating end-of-life conversations, assessing patient and caregiver needs, and patient/family centred planning in primary care practices to improve outcomes. The synthesis also explored how these functions aligned with critical community resources identified by patients/families dealing with end-of-life.
Methods
A realist synthesis is theory driven and iterative, involving the investigation of proposed program theories of how particular contexts catalyze mechanisms (program resources and individual reactions to resources) to generate improved outcomes. To assess whether program theories were supported and plausible, two librarian-assisted and several researcher-initiated purposive searches of the literature were conducted, then extracted data were analyzed and synthesized. To assess relevancy, health system partners and family advisors informed the review process.
Results
Twenty-eight articles were identified as being relevant and evidence was consolidated into two final program theories: 1) Making end-of-life discussions comfortable, and 2) Creating plans that reflect needs and values. Theories were explored in depth to assess the effect of multi-level contexts on primary care practices implementing tools or frameworks, strategies for improving end-of-life communications, or facilitators that could improve advance care planning by primary care practitioners.
Conclusions
Primary care practitioners’ use of tools to assess patients/families’ needs facilitated discussions and planning for end-of-life issues without specifically discussing death. Also, receiving training on how to better communicate increased practitioner confidence for initiating end-of-life discussions. Practitioner attitudes toward death and prior education or training in end-of-life care affected their ability to initiate end-of-life conversations and plan with patients/families. Recognizing and seizing opportunities when patients are aware of the need to plan for their end-of-life care, such as in contexts when patients experience transitions can increase readiness for end-of-life discussions and planning. Ultimately conversations and planning can improve patients/families’ outcomes.
Nitrate-fed and dark-stressed bean (Phaseolus vulgaris) and pea (Pisum sativum) plants were used to study nodule senescence. In bean, 1 d of nitrate treatment caused a partially reversible decline in ...nitrogenase activity and an increase in O2 diffusion resistance, but minimal changes in carbon metabolites, antioxidants, and other biochemical parameters, indicating that the initial decrease in nitrogenase activity was due to O2 limitation. In pea, 1 d of dark treatment led to a 96% decline in nitrogenase activity and sucrose, indicating sugar deprivation as the primary cause of activity loss. In later stages of senescence (4 d of nitrate or 2-4 d of dark treatment), nodules showed accumulation of oxidized proteins and general ultrastructural deterioration. The major thiol tripeptides of untreated nodules were homoglutathione (72%) in bean and glutathione (89%) in pea. These predominant thiols declined by approximately 93% after 4 d of nitrate or dark treatment, but the loss of thiol content can be only ascribed in part to limited synthesis by gamma-glutamylcysteinyl, homoglutathione, and glutathione synthetases. Ascorbate peroxidase was immunolocalized primarily in the infected and parenchyma (inner cortex) nodule cells, with large decreases in senescent tissue. Ferritin was almost undetectable in untreated bean nodules, but accumulated in the plastids and amyloplasts of uninfected interstitial and parenchyma cells following 2 or 4 d of nitrate treatment, probably as a response to oxidative stress.
Essential hypertension is a principal cardiovascular risk factor whose origin remains unknown. Classical genetic studies have shown that blood pressure is at least partially heritable, opening a ...window to understanding the pathophysiology of essential hypertension in the human using modern genetic tools. The Wellcome Trust Case Control Consortium has recently published the results of screening the genomes of 2000 essential hypertension cases and 3000 controls using 500 000 genome-wide single nucleotide polymorphisms (SNPs). None of the variants proved to be genome-wide significant after correction for multiple tests but the most significantly associated SNPs (P<10(-5)) constitute a priority list that warrant follow-up in other studies. We describe here replication studies of the top six SNPs in subjects from the US National Heart, Lung, and Blood Institute funded Family Blood Pressure Program comprising 11 433 individuals recruited by hypertensive families. The results suggest that only one of the six SNPs might be associated with essential hypertension in Americans of European origin. This SNP shows a significant but opposite effect in Americans of Hispanic origin and no association in African Americans. The significance of the opposing effect estimates is unclear. No replication could be shown for hypertension status, but there are differences in study design. This attempted replication highlights that essential hypertension studies will require more comprehensive and larger genetic screens.
The ability to taste phenylthiocarbamide (PTC) shows complex inheritance in humans. We obtained a quantitative measure of PTC tasting ability in 267 members of 26 large three-generation families that ...were part of a set of CEPH families that had been used for genetic mapping. Significant bimodality was found for the distribution of age and gender adjusted scores (P<0.001), with estimated means of 3.16 (SD=1.80) and 9.26 (SD=1.54). Using the extensive genotyping available in these families from the genetic mapping efforts, we performed a genome scan by using 1324 markers with an average spacing of 4 cM. Analyses were first carried out with a recessive genetic model that has traditionally been assumed for the trait, and a threshold score of 8.0 delineating tasters from non-tasters. In this qualitative analysis, the maximum genome-wide lod score was 4.74 at 246 cM on chromosome 7; 17 families showed segregation of the dichotomous PTC phenotype. No other lod scores were significant; the next highest score was on chromosome 10 (lod=1.64 at 85 cM), followed by chromosome 3 (lod=1.29 at 267 cM). Because PTC taste ability exhibited substantial quantitative variation, the quantitative trait was also analyzed by using a variance components approach in SOLAR. The maximum quantitative genome-wide lod score was 8.85 at 246 cM on chromosome 7. Evidence for other possible quantitative loci was found on chromosomes 1 (lod=2.31 at 344 cM) and 16 (lod=2.01 at 14 cM). A subsequent two-locus whole-genome scan conditional on the chromosome 7 quantitative trait locus identified the chromosome 16 locus (two-locus lod=3.33 at 14 cM).
IntroductionTo compare 1990-91 Gulf War Veterans (GWV) survival outcomes with a comparable cohort, UK’s Ministry of Defence and Canada’s Department of National Defence combined data from their ...respective cohorts. The survival estimates/comparisons emanating from this collaboration will be novel as they will control for healthy worker/soldier effect (HW/SE).
Objectives and ApproachGWV cohort building and record linkage methods used by Canada and the UK are described in more detail elsewhere. To ensure comparability in mortality outcomes between cohorts, the following steps will be conducted prior to analysis:
ICD-9 causes of death (COD) will be recoded to ICD-10; recoding by each country will be cross-validated by the other, to ensure high inter-coder reliability;
CODs will be analysed at the ICD-chapter level;
Calculated age- and sex-specific rates will be directly standardized using the WHO 2012-2022 Standard Population. Cox proportional hazards will be used to compare survival between cohorts.
ResultsWe are currently in the process of completing this exciting cross-sectoral linkage study and expect to have preliminary results to present. To our knowledge, this will be the first time that mortality outcomes for two discrete Gulf War veteran cohorts (ascertained by record linkage) will be analytically compared, rather than comparing to the general population. These findings will not only provide a more recent evaluation of the health status of GWV in Canada, but will also be a rare opportunity to control for the HW/SE, using comparisons with non-equivalent cohorts (e.g., general population, other deployment) cannot achieve.
Conclusion/ImplicationsBeyond evidence of a strong inter-sectoral research relationship between military nations, these findings also represent a feasible solution to controlling for the HW/SE. The ability to control for this will mean more accurate UK and Canada GWV mortality/survival estimates than either country can generate on their own.
Soybean lecithins are seeing increasing use in industry as an emulsifier and food additive. They are also a growing source of human food allergies, which arise principally from the proteins ...fractionating with the lecithin fraction during manufacture. A previous study (Gu, X.; Beardslee, T.; Zeece, M.; Sarath, G.; Markwwell, J. Int Arch. Allergy Immunol. 2001, 126, 218−225) identified several allergenic proteins in soybean lecithins and a soybean IgE-binding protein termed P39 was discovered. However, very little was known about this protein except that it was coded by the soybean genome. This paper investigates key biological and immunological properties of this potential soybean lecithin allergen. P39 is encoded by a multigene family in soybeans and in several other higher plants. The soybean P39-1 protein and its essentially indistinguishable homologue, P39-2, have been cloned and studied. These proteins and their homologues belong to a family of plant-specific proteins of unknown function. In soybeans, P39-1 is seed specific, and its transcript levels are highest in developing seeds and decline during seed maturation. In contrast, P39 protein was detectable only in the fully mature, dry seed. Subcellular fractionation revealed that P39 protein was strongly associated with oil bodies; however, immunolocalization indicated P39 was distributed in the matrix of the protein storage vacuoles, suggesting that association with oil bodies was an artifact arising from the extraction procedure. By the use of recombinant techniques it has also been documented that IgE-binding epitopes are present on several different portions of the P39-1 polypeptide.
Seed dormancy and germination are complex physiological processes usually under hormonal control. Germination of seeds from many plants including switchgrass, are inhibited by ABA and promoted by NO ...or ROS. However, ABA apparently requires both ROS and NO as intermediates in its action, with ROS produced by membrane-bound NADPH-oxidases responsive to ABA. In switchgrass seeds, externally supplied hydrogen peroxide (ROS), but not NO will overcome ABA-imposed inhibition of germination. Stimulation of germination by external ROS can be partially blocked by NO-scavengers, suggesting that NO is required for seed germination in switchgrass as well as for ABA-induced inhibition of germination. Collectively, these data suggest that multiple mechanisms might be required to sense and respond to varying levels of ABA, NO and ROS in switchgrass seeds.
The retrospective exhibition of the work of photographer Diane Arbus at the Museum of Modern Art in New York in 1972 drew particular censure from art critic Susan Sontag who disparaged Arbus's work ...for its unethical depiction of monsters and borderline cases. Baird proposes a conversation between Sontag and Arbus in order to re-examine Sontag's criticism of Arbus's work as predatory, even as Arbus was experimenting with sophisticated subject-photographer relationships that challenged traditional notions of documentary photography.
Hydrogen peroxide (H2O2) as a source of reactive oxygen species (ROS) significantly stimulated germination of switchgrass (Panicum virgatum L.) seeds with an optimal concentration of 20 mM at both 25 ...and 35°C. For non-dormant switchgrass seeds exhibiting different levels of germination, treatment with H2O2 resulted in rapid germination (<3 days) of all germinable seeds as compared to seeds placed on water. Exposure to 20 mM H2O2 elicited simultaneous growth of the root and shoot system, resulting in more uniform seedling development. Seeds of big bluestem (Andropogon gerardii Vitman) and indiangrass Sorghastrum nutans (L.) Nash also responded positively to H2O2 treatment, indicating the universality of the effect of H2O2 on seed germination in warm-season prairie grasses. For switchgrass seeds, abscisic acid (ABA) and the NADPH-oxidase inhibitor, diphenyleneiodonium (DPI) at 20 μM retarded germination (radicle emergence), stunted root growth and partially inhibited NADPH-oxidase activity in seeds. H2O2 reversed the inhibitory effects of DPI and ABA on germination and coleoptile elongation, but did not overcome DPI inhibition of root elongation. Treatment with H2O2 appeared to enhance endogenous production of nitric oxide, and a scavenger of nitric oxide abolished the peroxide-responsive stimulation of switchgrass seed germination. The activities and levels of several proteins changed earlier in seeds imbibed on H2O2 as compared to seeds maintained on water or on ABA. These data demonstrate that seed germination of warm-season grasses is significantly responsive to oxidative conditions and highlights the complex interplay between seed redox status, ABA, ROS and NO in this system.
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