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Sample records for stress resistance traits

  1. Geographic variation for climatic stress resistance traits in the sprintail Orchesella cincta

    DEFF Research Database (Denmark)

    Bahrndorff, Simon; Holmstrup, Martin; Petersen, H.

    2006-01-01

    Multiple traits of stress resistance were investigated in the epedaphic springtail Orchesella cincta. Second generation adults from five laboratory populations were compared with respect to resistance to extreme temperatures and desiccation, and traits relevant to climatic adaptation. Populations...... in stress resistance of springtails related to climatic conditions. Keywords: Geographic variation; Climatic change; Adaptation; Orchesella cincta; Soil ecosystems......Multiple traits of stress resistance were investigated in the epedaphic springtail Orchesella cincta. Second generation adults from five laboratory populations were compared with respect to resistance to extreme temperatures and desiccation, and traits relevant to climatic adaptation. Populations...

  2. A meta-analysis of quantitative trait loci for abiotic and biotic stress resistance in tetraploid cotton.

    Science.gov (United States)

    Abdelraheem, Abdelraheem; Liu, Feng; Song, Mingzhou; Zhang, Jinfa F

    2017-12-01

    The number and location of mapped quantitative trait loci (QTL) depend on genetic populations and testing environments. The identification of consistent QTL across genetic backgrounds and environments is a pre-requisite to marker-assisted selection. This study analyzed a total of 661 abiotic and biotic stress resistance QTL based on our previous work and other publications using the meta-analysis software Biomercator. It identified chromosomal regions containing QTL clusters for different resistance traits and hotspots for a particular resistance trait in cotton from 98 QTL for drought tolerance under greenhouse (DT) and 150 QTL in field conditions (FDT), 80 QTL for salt tolerance in the greenhouse conditions (ST), 201 QTL for resistance to Verticillium wilt (VW, Verticillium dahliae), 47 QTL for resistance to Fusarium wilt (FW, Fusarium oxysporum f. sp. vasinfectum), and 85 QTL for resistance to root-knot nematodes (RKN, Meloiodogyne incognita) and reniform nematodes (RN, Rotylenchulus reniformis). The traits used in QTL mapping for abiotic stress tolerance included morphological traits-plant height and fresh and dry shoot and root weights, physiological traits-chlorophyll content, osmotic potential, carbon isotope ratio, stomatal conductance, photosynthetic rate, transpiration, canopy temperature, and leaf area index, agronomic traits-seedcotton yield, lint yield, boll weight, and lint percent, and fiber quality traits-fiber length, uniformity, strength, elongation, and micronaire. The results showed that resistance QTL are not uniformly distributed across the cotton genome; some chromosomes carried disproportionally more QTL, QTL clusters, or hotspots. Twenty-three QTL clusters were found on 15 chromosomes (c3, c4, c5, c6, c7, c11, c14, c15, c16, c19, c20, c23, c24, c25, and c26). Moreover, 28 QTL hotshots were associated with different resistance traits including one hotspot on c4 for Verticillium wilt resistance, two QTL hotspots on c24 for chlorophyll

  3. AsrR Is an Oxidative Stress Sensing Regulator Modulating Enterococcus faecium Opportunistic Traits, Antimicrobial Resistance, and Pathogenicity

    Science.gov (United States)

    Lebreton, François; van Schaik, Willem; Sanguinetti, Maurizio; Posteraro, Brunella; Torelli, Riccardo; Le Bras, Florian; Verneuil, Nicolas; Zhang, Xinglin; Giard, Jean-Christophe; Dhalluin, Anne; Willems, Rob J. L.; Leclercq, Roland; Cattoir, Vincent

    2012-01-01

    Oxidative stress serves as an important host/environmental signal that triggers a wide range of responses in microorganisms. Here, we identified an oxidative stress sensor and response regulator in the important multidrug-resistant nosocomial pathogen Enterococcus faecium belonging to the MarR family and called AsrR (antibiotic and stress response regulator). The AsrR regulator used cysteine oxidation to sense the hydrogen peroxide which results in its dissociation to promoter DNA. Transcriptome analysis showed that the AsrR regulon was composed of 181 genes, including representing functionally diverse groups involved in pathogenesis, antibiotic and antimicrobial peptide resistance, oxidative stress, and adaptive responses. Consistent with the upregulated expression of the pbp5 gene, encoding a low-affinity penicillin-binding protein, the asrR null mutant was found to be more resistant to β-lactam antibiotics. Deletion of asrR markedly decreased the bactericidal activity of ampicillin and vancomycin, which are both commonly used to treat infections due to enterococci, and also led to over-expression of two major adhesins, acm and ecbA, which resulted in enhanced in vitro adhesion to human intestinal cells. Additional pathogenic traits were also reinforced in the asrR null mutant including greater capacity than the parental strain to form biofilm in vitro and greater persistance in Galleria mellonella colonization and mouse systemic infection models. Despite overexpression of oxidative stress-response genes, deletion of asrR was associated with a decreased oxidative stress resistance in vitro, which correlated with a reduced resistance to phagocytic killing by murine macrophages. Interestingly, both strains showed similar amounts of intracellular reactive oxygen species. Finally, we observed a mutator phenotype and enhanced DNA transfer frequencies in the asrR deleted strain. These data indicate that AsrR plays a major role in antimicrobial resistance and

  4. AsrR is an oxidative stress sensing regulator modulating Enterococcus faecium opportunistic traits, antimicrobial resistance, and pathogenicity.

    Directory of Open Access Journals (Sweden)

    François Lebreton

    Full Text Available Oxidative stress serves as an important host/environmental signal that triggers a wide range of responses in microorganisms. Here, we identified an oxidative stress sensor and response regulator in the important multidrug-resistant nosocomial pathogen Enterococcus faecium belonging to the MarR family and called AsrR (antibiotic and stress response regulator. The AsrR regulator used cysteine oxidation to sense the hydrogen peroxide which results in its dissociation to promoter DNA. Transcriptome analysis showed that the AsrR regulon was composed of 181 genes, including representing functionally diverse groups involved in pathogenesis, antibiotic and antimicrobial peptide resistance, oxidative stress, and adaptive responses. Consistent with the upregulated expression of the pbp5 gene, encoding a low-affinity penicillin-binding protein, the asrR null mutant was found to be more resistant to β-lactam antibiotics. Deletion of asrR markedly decreased the bactericidal activity of ampicillin and vancomycin, which are both commonly used to treat infections due to enterococci, and also led to over-expression of two major adhesins, acm and ecbA, which resulted in enhanced in vitro adhesion to human intestinal cells. Additional pathogenic traits were also reinforced in the asrR null mutant including greater capacity than the parental strain to form biofilm in vitro and greater persistance in Galleria mellonella colonization and mouse systemic infection models. Despite overexpression of oxidative stress-response genes, deletion of asrR was associated with a decreased oxidative stress resistance in vitro, which correlated with a reduced resistance to phagocytic killing by murine macrophages. Interestingly, both strains showed similar amounts of intracellular reactive oxygen species. Finally, we observed a mutator phenotype and enhanced DNA transfer frequencies in the asrR deleted strain. These data indicate that AsrR plays a major role in antimicrobial

  5. Genetic architecture of plant stress resistance: multi-trait genome-wide association mapping

    NARCIS (Netherlands)

    Thoen, H.P.M.; Davila Olivas, N.H.; Kloth, K.J.; Coolen, Silvia; Huang, P.; Aarts, M.G.M.; Molenaar, J.A.; Bakker, J.; Bouwmeester, H.J.; Broekgaarden, C.; Bucher, J.; Busscher-Lange, J.; Cheng, X.; Dijk-Fradin, van E.F.; Jongsma, M.A.; Julkowska, Magdalena M.; Keurentjes, J.J.B.; Ligterink, W.; Pieterse, Corné M.J.; Ruyter-Spira, C.P.; Smant, G.; Schaik, van C.C.; Wees, van Saskia C.M.; Visser, R.G.F.; Voorrips, R.E.; Vosman, B.; Vreugdenhil, D.; Warmerdam, S.; Wiegers, G.L.; Heerwaarden, van J.; Kruijer, W.T.; Eeuwijk, van F.A.; Dicke, M.

    2017-01-01

    Plants are exposed to combinations of various biotic and abiotic stresses, but stress responses are usually investigated for single stresses only. Here, we investigated the genetic architecture underlying plant responses to 11 single stresses and several of their combinations by phenotyping 350

  6.     Developmental acclimation affects clinal variation in stress resistance traits in Drosophila buzzatii

    DEFF Research Database (Denmark)

    Sarup, Pernille Merete; Loeschcke, Volker

    2010-01-01

      Patterns of clinal genetic variation in Drosophila are often characterized after rearing at constant temperatures. However, clinal patterns might change after acclimation if populations differ in their plastic response to fluctuating environments. We studied longevity, starvation and heat knock...... temperatures, especially in heat knock-down, for which clinal patterns disappeared when flies were reared at constant temperatures. This result emphasises the importance of determining whether populations originating from different environments differ in their plastic responses to stress....

  7. Ecologically relevant stress resistance: from microarrays and ...

    Indian Academy of Sciences (India)

    Unknown

    2004-10-15

    Oct 15, 2004 ... quantitative trait loci to candidate genes – A research plan and preliminary results using ... [Loeschcke V, Sørensen J G and Kristensen T N 2004 Ecologically relevant stress resistance: from microarrays and quantitative trait loci to candidate genes ..... heritability of fitness and non-fitness traits (fertility, heat.

  8. Ecologically relevant stress resistance: from microarrays and ...

    Indian Academy of Sciences (India)

    2004-10-15

    Oct 15, 2004 ... Home; Journals; Journal of Biosciences; Volume 29; Issue 4. Ecologically relevant stress resistance: from microarrays and quantitative trait loci to candidate genes – A research plan and preliminary results using Drosophila as a model organism and climatic and genetic stress as model stresses.

  9. Mapping quantitative trait loci for fruit traits and powdery mildew resistance in melon (Cucumis melo)

    National Research Council Canada - National Science Library

    Wang, Yu-Hua; Wu, Dong-Hong; Huang, Jin-Hsing; Tsao, Shing-Jy; Hwu, Kae-Kang; Lo, Hsiao-Feng

    2016-01-01

    ... and disease resistance is required.The F2 populations from the cross of TARI-08874 (Cucumis melo ssp. melo) and ‘Bai-li-gua’ (C. melo ssp. agrestis) were used to map the quantitative trait loci...

  10. INVESTIGATION THE RELATIONSHIP BETWEEN JOB TRAITS AND JOB STRESS

    OpenAIRE

    GholamReza Jandagh; Sayed Mojtaba Hosseini Fard; Mohammad Saadatmand; Ismaeil Chezani Sharahi; Mahtab Rajabi

    2011-01-01

    Stress is a highly serious problem in today world which endangers physical and mental health of individuals. Today organization is a location seriously influenced by stress. As a calamity, stress in organizations weakens and destroys operations and also can promote the organization. There are paramount evidences on the destructive effects of job stress on physical and mental health as well as organizational productivity. Job or job traits are factors that highly impact on stress at organizati...

  11. Correlation between agronomic and stem borer resistant traits in ...

    African Journals Online (AJOL)

    SARAH

    2015-06-30

    Jun 30, 2015 ... Keywords: Correlated responses, heritability, secondary traits, selection, stem borer resistance. INTRODUCTION. Among insect pests of maize, stem borers are the most damaging and widespread in West and. Central Africa. Breeding for host plant resistance has been suggested as the most promising.

  12. The heat shock protein/chaperone network and multiple stress resistance

    KAUST Repository

    Jacob, Pierre

    2016-11-15

    Crop yield has been greatly enhanced during the last century. However, most elite cultivars are adapted to temperate climates and are not well suited to more stressful conditions. In the context of climate change, stress resistance is a major concern. To overcome these difficulties, scientists may help breeders by providing genetic markers associated with stress resistance. However, multi-stress resistance cannot be obtained from the simple addition of single stress resistance traits. In the field, stresses are unpredictable and several may occur at once. Consequently, the use of single stress resistance traits is often inadequate. Although it has been historically linked with the heat stress response, the heat shock protein (HSP)/chaperone network is a major component of multiple stress responses. Among the HSP/chaperone

  13. Resistance to infectious diseases is a heritable trait in rabbits.

    Science.gov (United States)

    Gunia, M; David, I; Hurtaud, J; Maupin, M; Gilbert, H; Garreau, H

    2015-12-01

    Selection for disease resistance is a powerful way to improve the health status of herds and to reduce the use of antibiotics. The objectives of this study were to estimate 1) the genetic parameters for simple visually assessed disease syndromes and for a composite trait of resistance to infectious disease including all syndromes and 2) their genetic correlations with production traits in a rabbit population. Disease symptoms were recorded in the selection herds of 2 commercial paternal rabbit lines during weighing at the end of the test (63 and 70 d of age, respectively). Causes of mortality occurring before these dates were also recorded. Seven disease traits were analyzed: 3 elementary traits visually assessed by technicians on farm (diarrhea, various digestive syndromes, and respiratory syndromes), 2 composite traits (all digestive syndromes and all infectious syndromes), and 2 mortality traits (digestive mortality and infectious mortality). Each animal was assigned only 1 disease trait, corresponding to the main syndrome ( = 153,400). Four production traits were also recorded: live weight the day before the end of test on most animals ( = 137,860) and cold carcass weight, carcass yield, and perirenal fat percentage of the carcass on a subset of slaughtered animals ( = 13,765). Records on both lines were analyzed simultaneously using bivariate linear animal models after validation of consistency with threshold models applied to logit-transformed traits. The heritabilities were low for disease traits, from 0.01 ± 0.002 for various digestive syndromes to 0.04 ± 0.004 for infectious mortality, and moderate to high for production traits. The genetic correlations between digestive syndromes were high and positive, whereas digestive and respiratory syndromes were slightly negatively correlated. The genetic correlations between the composite infectious disease trait and digestive or respiratory syndromes were moderate. Genetic correlations between disease and

  14. Personality Traits and Occupational Stress among Chinese Academics

    Science.gov (United States)

    Zhang, Li-Fang

    2012-01-01

    The primary objective of this study was to examine the predictive power of personality traits for occupational stress among Chinese university academics. Two hundred and forty-six participants responded to the NEO Five-Factor Inventory and the Occupational Stress Inventory-Revised. Results indicated that the strongest predictor for occupational…

  15. Personality Traits as Predictors of Stress among female Teachers in ...

    African Journals Online (AJOL)

    The paper investigated the stress level of female teachers in Osun State Teaching Service and determined the relationship between stress and each of the personality traits of self concept, extraversion, locus of control and achievement motivation. Using a sample of 370 teachers drawn from 50 randomly selected primary ...

  16. Plant traits affecting thrips resistance in cabbage

    OpenAIRE

    Voorrips, R.E.; Steenhuis-Broers, M.M.; Tiemens-Hulscher, M.; Lammerts Van Bueren, E.

    2008-01-01

    The development of thrips populations and thrips damage in 15 cabbage varieties was monitored in two years of field experiments in the Netherlands.. A number of morphological and physiological plant traits were also measured. The most important factors leading to a low level of thrips damage were late development of a compact head, a low Brix value and a high amount of leaf wax. Two open-pollinated cabbage varieties with low and high susceptibility to thrips damage were crossed in both recip...

  17. Relation between parenting stress and psychopathic traits among children.

    Science.gov (United States)

    Fite, Paula J; Greening, Leilani; Stoppelbein, Laura

    2008-01-01

    Parenting stress was examined as a correlate of psychopathic traits, specifically narcissism, callous/unemotional traits, and impulsivity, among school-aged children while controlling for the variance explained by aggressive behavior. Participants included 212 children ranging from 6 to 12 years of age (M = 8.3 years) who were admitted to an acute child psychiatric inpatient unit for treatment. Parents completed standardized measures of aggression (Child Behavior Checklist; CBCL), psychopathic traits (Antisocial Process Screening Device; APSD), and parenting stress (Parenting Stress Index; PSI) at the time of the child's admission. Multiple regression analyses revealed that high levels of the PSI dimension attachment difficulties were associated with high levels of narcissism and callous/unemotional traits among the children while statistically controlling for aggression. The PSI dimension role restriction was also found to be negatively related to narcissism. These findings suggest that specific aspects of parenting stress may be related to child psychopathic traits and might aid with conceptualizing and developing treatment approaches for childhood behavior problems. (c) 2008 John Wiley & Sons, Ltd.

  18. Correlations between insect resistance and horticultural traits in potatoes

    Directory of Open Access Journals (Sweden)

    Velci Queiroz de Souza

    2006-01-01

    Full Text Available The objective of this study was to determine relationships between insect resistance and some horticulturaltraits and the implications on selection. A potato population of 11 clonal families derived from crosses between insect resistantand genotypes adapted to the southern region of Brazil was used. The following traits were evaluated: plant size and vigor,incidence of insect attacks on leaves and tubers, tuber yield and appearance components. Phenotypic and genotypic correlationsbetween leaf and tuber resistance were not significant for the population, while phenotypic correlations between the tworesistance types were significant for individual families, with exception of the family originated from the cross involving‘ND263-32’. The incidence of insect attacks on tubers was significantly correlated with tuber yield and appearance in familiesderived from crosses of ‘NYL235-4’. The manifold correlations of leaf resistance with horticultural traits for all families weresignificant and unfavorable.

  19. Longitudinal Study on Reciprocity between Personality Traits and Parenting Stress

    Science.gov (United States)

    Rantanen, Johanna; Tillemann, Kati; Metsäpelto, Riitta-Leena; Kokko, Katja; Pulkkinen, Lea

    2015-01-01

    Reciprocal associations between the Big Five personality traits and parenting stress--including both parents' feelings of their distress and perception of their incompetence as parents--were studied with 248 participants (49% of which were males). Longitudinal data, collected at ages 33/36, 42 and 50 years, were used. Cross-lagged path analysis…

  20. Experimental Evidence for Nutrition Regulated Stress Resistance in Drosophila ananassae

    OpenAIRE

    Seema Sisodia; Singh, Bashisth N.

    2012-01-01

    BACKGROUND: The amount and quality of nutrients consumed by organisms have a strong impact on stress resistance, life-history traits and reproduction. The balance between energy acquisition and expenditure is crucial to the survival and reproductive success of animals. The ability of organisms to adjust their development, physiology or behavior in response to environmental conditions, called phenotypic plasticity, is a defining property of life. One of the most familiar and important examples...

  1. Mapping of quantitative trait loci (QTL) for production, resistance and tolerance traits in Salix. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Roennberg-Waestljung, Ann Christin; Bertholdsson, Nils-Ove; Glynn, Carolyn; Weih, Martin; Aahman, Inger [SLU, Uppsala (Sweden). Dept. of Plant Biology and Forest Genetics

    2004-05-01

    Quantitative trait loci (QTL) for growth traits, water use efficiency and tolerance/resistance against metals and herbivores have been identified. A hybrid F2 population originating from a cross between a Salix dasyclados-clone (SW901290) and a S. viminalis-clone ('Jorunn') was used for the different studies in this project. The growth response was analyzed in a greenhouse experiment with two water treatments, normal and drought. In addition, three field experiments with contrasting soils and climates were established. QTL specific for each treatment or field environment but also QTL stable over the treatments or field environments were detected. Each QTL explained from 8 to 29 % of the phenotypic variation depending on trait, treatment or field environment. Clusters of QTL for different traits were mapped indicating a common genetic base or tightly-linked QTL. Stable QTL identified for dryweight can be useful tools for early selection in Salix. In a separate greenhouse experiment, with a subset of ten genotypes from the F2 population, we show that genotype is more important than irrigation treatment for production of phenolic substances as well as for resistance to herbivory by P vulgatissima.

  2. Gender roles and traits in stress and health

    Directory of Open Access Journals (Sweden)

    Eric eMayor

    2015-06-01

    Full Text Available Women have a life-expectancy advantage over men, but a marked disadvantage with regards to morbidity. This is known as the female-male health-survival paradox in disciplines such as medicine, medical sociology and epidemiology. Individual differences in physical and mental health are further notably explained by the degree of stress individuals endure, with women being more affected by stressors than men. Here, we briefly examine the literature on women’s disadvantage in health and stress. Beyond biological considerations, we follow with socio-cognitive explanations of gender differences in health and stress. We show that gender roles and traits (masculinity in particular explain part of the gender differences in stress, notably cognitive appraisal and coping. Stress in turn degrades health. Implications are discussed. In conclusion, traditional socialization is advantageous for men in terms of health.

  3. Associations between APOE variants and metabolic traits and the impact of psychological stress.

    Directory of Open Access Journals (Sweden)

    Sofia I Iqbal Kring

    2011-01-01

    Full Text Available In a previous study, we observed that associations between APOE rs439401 and metabolic traits were moderated by chronic stress. Thus, in a population of stressed and non-stressed Danish men, we examined whether associations between APOE rs439401 and a panel of metabolic quantitative traits, all metabolic traits which may lead to T2D and CVD were moderated by psychological stress.Obese young men (n = 475, BMI ≥ 31.0 kg/m(2 and a randomly selected control group (n = 709 identified from a population of 141,800 men were re-examined in two surveys (S-46: mean age 46, S-49: mean age 49 years where anthropometric and biochemical measures were available. Psychological stress factors were assessed by a self-administered 7-item questionnaire. Each item had the possible response categories "yes" and "no" and assessed familial problems and conflicts. Summing positive responses constituted a stress item score, which was then dichotomized into stressed and non-stressed. Logistic regression analysis, applying a recessive genetic model, was used to assess odds ratios (OR of the associations between APOE rs439401 genotypes and adverse levels of metabolic traits.The APOE rs439401 TT-genotype associated positively with BMI (OR = 1.09 [1.01; 1.17], waist circumference (OR = 1.09 [1.02; 1.17] in stressed men at S-46. Positive associations were observed for fasting plasma glucose (OR = 1.42 [1.07; 1.87], serum triglycerides (OR = 1.41 [1.05; 1.91] and with fasting plasma insulin (OR = 1.48 [1.05; 2.08] in stressed men at S-49. Rs439401 TT-genotype also associated positively with surrogate measures of insulin resistance (HOMA-IR; OR = 1.21 [1.03; 1.41] and inversely with insulin sensitivity (Stumvoll index; OR = 0.90 [0.82; 0.99], BIGTT-S(I; OR = 0.60 [0.43; 0.85] in stressed men. No significant associations were observed in non-stressed men, albeit the estimates showed similar but weaker trends as in stressed men.The present results suggest that the APOE rs439401

  4. Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?

    Science.gov (United States)

    Pallarés, Susana; Velasco, Josefa; Millán, Andrés; Bilton, David T; Arribas, Paula

    2016-01-01

    Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions. We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species. Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens' initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available. Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin.

  5. Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?

    Directory of Open Access Journals (Sweden)

    Susana Pallarés

    2016-08-01

    Full Text Available Background Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions. Methods We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters. We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate under controlled exposure to desiccation, and explored their variability within and between species. Results Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens’ initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available. Discussion Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin.

  6. Biological stress responses in high and low trait anxious students.

    Science.gov (United States)

    Davis, D D; Dunlop, S R; Shea, P; Brittain, H; Hendrie, H C

    1985-08-01

    In an investigation of biological indicators of stress in normal humans, undergraduate psychology students were differentiated on trait anxiety and assessed under baseline, preexam (stress), and postexam conditions. Assessment at each condition involved drawing 20 ml of blood, followed by self-reporting for selected questionnaires. Self-reports included state anxiety, general psychological symptomatology, dysfunctional attitudes, academic confidence, sleep patterns, and intake of drugs, including alcohol and caffeine. Blood was analyzed for whole blood serotonin content, plasma MHPG, and platelet imipramine binding. Baseline differences between high and low trait anxious students on biological measures were significant only for whole blood serotonin content. Variation across situational conditions was significant for whole blood serotonin, with an increase under the stressful condition for both anxiety groups. Thus, serotonin is highlighted as an important factor in the human response to stress, whereas expected differences in MHPG were not observed. The serotonergic response to stress was not explained by changes in psychological or physical state variables. Changes in serotonin content were positively correlated with changes in platelet imipramine binding.

  7. Identifying leaf traits that signal stress in TIR spectra

    Science.gov (United States)

    Buitrago Acevedo, Maria F.; Groen, Thomas A.; Hecker, Christoph A.; Skidmore, Andrew K.

    2017-03-01

    Plants under constant water and temperature stress experience a chain of reactions that in the long term alter their leaf traits (morphology, anatomy and chemistry). The use of these traits as proxies for assessing plant stress was so far mainly based on conventional laboratory methods, which are expensive and time-consuming. Remote sensing methods based on spectral changes can detect changes in pigments and productivity using the visible and near infrared. However, the use of infrared spectra, where changes in the spectra are associated with physical changes of the leaf, is still incipient. In this study plants of Rhododendron cf. catawbiense, were exposed to low temperatures and low soil water content during a six months experiment. The spectral response in the infrared region 1.4-16 μm, microstructural variables, leaf water content, leaf area and leaf molecules such as lignin and cellulose concentrations were measured in individual leaves after the period of stress. This study revealed that under cold conditions plants have most changes in leaf water content, lignin and cellulose concentrations and leaf area, while under drought conditions the most striking change is water loss. These leaf trait modifications are also correlated with changes in thermal infrared spectra, showing their potential as proxies for detecting plant stress in this species. A multinomial model allows the estimation of the stress treatments imposed on these plants from their infrared spectra. This model reveals a group of 15 bands in the SWIR and MWIR between 2.23 and 7.77 μm, which show relatively large changes, and had an overall accuracy of 87%. Finally, individual partial least squares regression models show that lignin, cellulose, leaf water content and leaf area are the leaf traits reacting significantly to long-term stress and that are also generating measurable changes in the infrared spectra. Although these models are based on laboratory data, the congruence of the identified

  8. Trait associations in common bean genotypes grown under drought stress and field infestation by BSM bean fly

    Directory of Open Access Journals (Sweden)

    Daniel Ambachew

    2015-08-01

    Full Text Available Understanding functional relations among plant traits and their modulation by growing conditions is imperative in designing selection strategies for breeding programs. This study assessed trait relationships among 196 common bean genotypes exposed to stresses for drought and field infestation of bean fly or bean stem maggot (BSM. The study was carried out at two locations and data was analyzed with linear correlation, path coefficient and genotype × trait biplot analyses. Multiple trait data related to mechanisms of drought and bean fly tolerance were collected on 196 genotypes grown under i water deficit at mid-pod fill, or ii unprotected against bean fly; iii irrigated, well watered conditions, or iv bean fly protection with chemicals. Seed yield exhibited positive and significant correlations with leaf chlorophyll content, vertical root pulling resistance, pod harvest index, pods per plant and seeds per pod at both phenotypic and genotypic levels under stress and non-stress conditions. Genotypic correlations of traits with seed yield were greater than their respective phenotypic correlations across environments indicating the greater contribution of genotypic factors to the trait correlation. Pods per plant and seeds per pod had high positive direct effects on seed yield both under stress and non-stress whereas pods per plant had the highest indirect effect on seed yield through pod harvest index under stress. In general, our results suggest that vertical root pulling resistance and pod harvest index are important selection objectives for improving seed yield in common beans under non-stress and stress conditions, and particularly useful for drought and BSM tolerance evaluation.

  9. Carcass and meat quality traits of rabbits under heat stress.

    Science.gov (United States)

    Zeferino, C P; Komiyama, C M; Fernandes, S; Sartori, J R; Teixeira, P S S; Moura, A S A M T

    2013-03-01

    Rabbits are very sensitive to heat stress because they have difficulty eliminating excess body heat. The objective of the current study was to evaluate the effects of heat stress on slaughter weight, dressing percentage and carcass and meat quality traits of rabbits from two genetic groups. Ninety-six weaned rabbits were used: half were from the Botucatu genetic group and half were crossbreds between New Zealand White sires and Botucatu does. They were assigned to a completely randomized design in a 2 × 3 factorial arrangement (two genetic groups and three ambient temperatures: 18°C, 25°C and 30°C) and kept under controlled conditions in three environmental chambers from 5 to 10 weeks of age. Slaughter took place at 10 weeks, on 2 consecutive days. Meat quality measurements were made in the longissimus muscle. Actual average ambient temperature and relative humidity in the three chambers were 18.4°C and 63.9%, 24.4°C and 80.2% and 29.6°C and 75.9%, respectively. Purebred rabbits were heavier at slaughter and had heavier commercial and reference carcasses than crossbreds at 30°C; however, no differences between genetic groups for these traits were found at lower temperatures. No genetic group × ambient temperature interaction was detected for any other carcass or meat quality traits. The percentages of distal parts of legs, skin and carcass forepart were higher in crossbred rabbits, indicating a lower degree of maturity at slaughter in this group. The percentage of thoracic viscera was higher in the purebreds. Lightness of the longissimus muscle was higher in the purebreds, whereas redness was higher in the crossbreds. Slaughter, commercial and reference carcass weights and the percentages of thoracic viscera, liver and kidneys were negatively related with ambient temperature. Commercial and reference carcass yields, and the percentage of distal parts of legs, on the other hand, had a positive linear relationship with ambient temperature. Meat redness and

  10. The use of metabolomic quantitative trait locus mapping and osmotic adjustment traits for the improvement of crop yields under environmental stresses.

    Science.gov (United States)

    Abdelrahman, Mostafa; Burritt, David J; Tran, Lam-Son Phan

    2017-06-28

    The sustainable production of food to feed an increasing world population is a major challenge for plant scientists, especially due to the unpredictable and dynamic nature of global climatic conditions. Heat waves, drought, increased soil salinity, unseasonal cold and flooding are all becoming more common climate-related causes of stress for crop plants, and are already affecting yields and the geographical distributions of optimal growing regions for many crops. Therefore, the development and application of multi-faceted strategies, including sustainable agricultural practices and the development and cultivation of new varieties containing genetic traits associated with abiotic stress tolerance, will either alone or together be essential to sustainably grow high-yielding crops under increasingly stressful environmental conditions. The development of abiotic stress-resilient crops requires an in-depth knowledge of plant development and of the biological processes that enable plants to survive in stressful environments, and this knowledge can be obtained from "omic" studies, such as bioinformatics, genomics, transcriptomics, proteomics and metabolomics. The plant metabolome can provide a snapshot of the physiological and biochemical status of a plant cell under normal or stressful conditions, and thus it is closely related to the plant phenotypes. Analysis of the metabolomes of plants grown under stressful conditions can be used to identify stress resistance-associated metabolites or biomarkers, which can then be used by plant breeders as selective markers to help identify the phenotypes, resulted from the complex interactions between genotype and environment. Osmotic adjustment is an important metabolic adaptation mechanism which helps plants survive abiotic stress and can support higher crop yield under stressful environmental conditions. This review highlights the recent advances in our understanding of the functions of abiotic stress-responsive metabolites, with

  11. Associations between APOE variants and metabolic traits and the impact of psychological stress

    DEFF Research Database (Denmark)

    Kring, Sofia Inez Iqbal; Barefoot, John; Brummett, Berverly H.

    2011-01-01

    In a previous study, we observed that associations between APOE rs439401 and metabolic traits were moderated by chronic stress. Thus, in a population of stressed and non-stressed Danish men, we examined whether associations between APOE rs439401 and a panel of metabolic quantitative traits, all m...... metabolic traits which may lead to T2D and CVD were moderated by psychological stress....

  12. Quantitative resistance can lead to evolutionary changes in traits not targeted by the resistance QTLs

    Science.gov (United States)

    Van den Berg, Femke; Lannou, Christian; Gilligan, Christopher A; van de Bosch, Frank

    2014-01-01

    This paper addresses the general concern in plant pathology that the introduction of quantitative resistance in the landscape can lead to increased pathogenicity. Hereto, we study the hypothetical case of a quantitative trait loci (QTL) acting on pathogen spore production per unit lesion area. To regain its original fitness, the pathogen can break the QTL, restoring its spore production capacity leading to an increased spore production per lesion. Or alternatively, it can increase its lesion size, also leading to an increased spore production per lesion. A data analysis shows that spore production per lesion (affected by the resistance QTL) and lesion size (not targeted by the QTL) are positively correlated traits, suggesting that a change in magnitude of a trait not targeted by the QTL (lesion size) might indirectly affect the targeted trait (spore production per lesion). Secondly, we model the effect of pathogen adaptation towards increased lesion size and analyse its consequences for spore production per lesion. The model calculations show that when the pathogen is unable to overcome the resistance associated QTL, it may compensate for its reduced fitness by indirect selection for increased pathogenicity on both the resistant and susceptible cultivar, but whereby the QTLs remain effective. PMID:24665339

  13. Combination of Multiple Resistance Traits from Wild Relative Species in Chrysanthemum via Trigeneric Hybridization

    Science.gov (United States)

    Deng, Yanming; Jiang, Jiafu; Chen, Sumei; Teng, Nianjun; Song, Aiping; Guan, Zhiyong; Fang, Weimin; Chen, Fadi

    2012-01-01

    Background With the objective of combining multiple resistant traits from wild relative species in florist’s chrysanthemums, trigeneric hybridization was conducted by crossing two intergeneric F1 hybrids Chrysanthemum grandiflorum × Artemisia vulgaris and Chrysanthemum crassum × Crossostephium chinense. Methodology/Principal Findings To assess post-pollination phenomena, we investigated pollen germination on the stigma and embryo development, using fluorescence and scanning electron microscopy and paraffin-embedded sections, respectively. We selected eight putative trigeneric hybrid lines that showed the greatest morphological differences from the parents from among the progeny derived via embryo rescue. The hybridity of one trigeneric hybrid was further confirmed by fluorescent genomic in situ hybridization; in addition, the aphid resistance and salt tolerance of this hybrid were higher than those of the chrysanthemum parent and the C. grandiflorum × A. vulgaris F1 hybrid, respectively. Conclusions/Significance The enhanced aphid resistance of the hybrid line reflects the inheritance of chromosomes from A. vulgaris, which carries genes that encode bioactive components. The enhanced salt tolerance of the trigeneric hybrid is attributable to inheritance of genetic materials from Chrysanthemum crassum and Crossostephium chinense, which act to maintain the compartmentation of Na+ and K+ ions and their selective transportation among different organs to avert deleterious effects and protect the photosynthetic apparatus. The results indicate that trigeneric hybridization between different bigeneric hybrids is a promising method for combination of multiple stress-resistance traits for improvement of chrysanthemum. PMID:22952958

  14. Combination of multiple resistance traits from wild relative species in Chrysanthemum via trigeneric hybridization.

    Science.gov (United States)

    Deng, Yanming; Jiang, Jiafu; Chen, Sumei; Teng, Nianjun; Song, Aiping; Guan, Zhiyong; Fang, Weimin; Chen, Fadi

    2012-01-01

    With the objective of combining multiple resistant traits from wild relative species in florist's chrysanthemums, trigeneric hybridization was conducted by crossing two intergeneric F(1) hybrids Chrysanthemum grandiflorum × Artemisia vulgaris and Chrysanthemum crassum × Crossostephium chinense. To assess post-pollination phenomena, we investigated pollen germination on the stigma and embryo development, using fluorescence and scanning electron microscopy and paraffin-embedded sections, respectively. We selected eight putative trigeneric hybrid lines that showed the greatest morphological differences from the parents from among the progeny derived via embryo rescue. The hybridity of one trigeneric hybrid was further confirmed by fluorescent genomic in situ hybridization; in addition, the aphid resistance and salt tolerance of this hybrid were higher than those of the chrysanthemum parent and the C. grandiflorum × A. vulgaris F(1) hybrid, respectively. The enhanced aphid resistance of the hybrid line reflects the inheritance of chromosomes from A. vulgaris, which carries genes that encode bioactive components. The enhanced salt tolerance of the trigeneric hybrid is attributable to inheritance of genetic materials from Chrysanthemum crassum and Crossostephium chinense, which act to maintain the compartmentation of Na(+) and K(+) ions and their selective transportation among different organs to avert deleterious effects and protect the photosynthetic apparatus. The results indicate that trigeneric hybridization between different bigeneric hybrids is a promising method for combination of multiple stress-resistance traits for improvement of chrysanthemum.

  15. Phenotypic heterogeneity is a selected trait in natural yeast populations subject to environmental stress

    Science.gov (United States)

    Holland, Sara L; Reader, Tom; Dyer, Paul S; Avery, Simon V

    2014-01-01

    Populations of genetically uniform microorganisms exhibit phenotypic heterogeneity, where individual cells have varying phenotypes. Such phenotypes include fitness-determining traits. Phenotypic heterogeneity has been linked to increased population-level fitness in laboratory studies, but its adaptive significance for wild microorganisms in the natural environment is unknown. Here, we addressed this by testing heterogeneity in yeast isolates from diverse environmental sites, each polluted with a different principal contaminant, as well as from corresponding control locations. We found that cell-to-cell heterogeneity (in resistance to the appropriate principal pollutant) was prevalent in the wild yeast isolates. Moreover, isolates with the highest heterogeneity were consistently observed in the polluted environments, indicating that heterogeneity is positively related to survival in adverse conditions in the wild. This relationship with survival was stronger than for the property of mean resistance (IC50) of an isolate. Therefore, heterogeneity could be the major determinant of microbial survival in adverse conditions. Indeed, growth assays indicated that isolates with high heterogeneities had a significant competitive advantage during stress. Analysis of yeasts after cultivation for ≥ 500 generations additionally showed that high heterogeneity evolved as a heritable trait during stress. The results showed that environmental stress selects for wild microorganisms with high levels of phenotypic heterogeneity. PMID:24000788

  16. Experimental evidence for nutrition regulated stress resistance in Drosophila ananassae.

    Directory of Open Access Journals (Sweden)

    Seema Sisodia

    Full Text Available BACKGROUND: The amount and quality of nutrients consumed by organisms have a strong impact on stress resistance, life-history traits and reproduction. The balance between energy acquisition and expenditure is crucial to the survival and reproductive success of animals. The ability of organisms to adjust their development, physiology or behavior in response to environmental conditions, called phenotypic plasticity, is a defining property of life. One of the most familiar and important examples of phenotypic plasticity is the response of stress tolerance and reproduction to changes in developmental nutrition. Larval nutrition may affect a range of different life-history traits as well as responses to environmental stress in adult. PRINCIPAL FINDINGS: Here we investigate the effect of larval nutrition on desiccation, starvation, chill-coma recovery, heat resistance as well as egg to adult viability, egg production and ovariole number in Drosophila ananassae. We raised larvae on either protein rich diet or carbohydrate rich diet. We found that flies consuming protein rich diet have higher desiccation and heat shock resistance whereas flies developed on carbohydrate rich diet have higher starvation and cold resistance. Egg production was higher in females developed on protein rich diet and we also found trade-off between egg production and Egg to adult viability of the flies. Viability was higher in carbohydrate rich diet. However, sex specific viability was found in different nutritional regimes. Higher Egg production might be due to higher ovariole number in females of protein rich diet. CONCLUSION: Thus, Drosophila ananassae adapts different stress tolerance and life-history strategies according to the quality of the available diet, which are correlated with phenotypic adjustment at anatomical and physiological levels.

  17. A Quantitative Genomic Approach for Analysis of Fitness and Stress Related Traits in a Drosophila melanogaster Model Population

    DEFF Research Database (Denmark)

    Rohde, Palle Duun; Krag, Kristian; Loeschcke, Volker

    2016-01-01

    , to investigate whether this population harbors genetic variation for a set of stress resistance and life history traits. Using a genomic approach, we found substantial genetic variation for metabolic rate, heat stress resistance, expression of a major heat shock protein, and egg-to-adult viability investigated...... at a benign and a higher stressful temperature. This suggests that these traits will be able to evolve. In addition, we outline an approach to conduct pathway associations based on genomic linear models, which has potential to identify adaptive genes and pathways, and therefore can be a valuable tool...

  18. Costs of antibiotic resistance – separating trait effects and selective effects

    National Research Council Canada - National Science Library

    Hall, Alex R; Angst, Daniel C; Schiessl, Konstanze T; Ackermann, Martin

    2015-01-01

    ... the mechanism of resistance and genetic background. Here, we suggest that such variation can be better understood by distinguishing between the effects of resistance mechanisms on individual traits such as growth rate or yield...

  19. Stress-related changes in personality: A longitudinal study of perceived stress and trait pessimism.

    Science.gov (United States)

    Shields, Grant S; Toussaint, Loren L; Slavich, George M

    2016-10-01

    Although research has shown that certain aspects of personality can change over time, the determinants of such change remain unclear. Stress alters neural dynamics and precipitates disorders that shape personality traits involving negative affectivity. In this study, therefore, we assessed the perceived stress and pessimism levels of 332 young, middle-aged, and older adults for five weeks to examine how levels of stress and pessimism change and interrelate over time. The best fitting longitudinal model was a bivariate latent growth curve model, which indicated that stress and pessimism both changed and exhibited significant variability in change over time. Moreover, changes in stress were associated with changes in pessimism. Pessimism thus changes over time, with alterations in stress potentially structuring these changes.

  20. Blunted cardiac reactivity to psychological stress associated with higher trait anxiety: a study in peacekeepers.

    Science.gov (United States)

    Souza, Gabriela Guerra Leal; Mendonça-de-Souza, Ana Carolina Ferraz; Duarte, Antônio Fernando Araújo; Fischer, Nastassja Lopes; Souza, Wanderson Fernandes; Coutinho, Evandro Silva Freire; Figueira, Ivan; Volchan, Eliane

    2015-11-23

    Both exaggerated and diminished reactivity to stress can be maladaptive. Previous studies have shown that performing increasingly difficult tasks leads first to increased reactivity and then to a blunted response when success is impossible. Our aim was to investigate the influence of trait anxiety on cardiac and cortisol response to and recovery from a standardized psychosocial stress task (Trier Social Stress Task) in a homogeneous sample of healthy peacekeepers. We hypothesized that participants with higher trait anxiety would show blunted reactivity during the performance of an overwhelmingly difficult and stressful task. Participants (N = 50) delivered a speech and performed an arithmetic task in the presence of critical evaluators. Cortisol samples and electrocardiogram data were collected. Participants completed the State-Trait Anxiety Inventory-Trait version, the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C) and the Military Peace Force Stressor Inventory. For heart rate, the findings showed that peacekeepers with higher trait anxiety reacted less to the speech task (p = 0.03) and to the arithmetic task (p = 0.008) than those with lower trait anxiety. Trait anxiety did not modulate cortisol responses to the task. Despite the high trait anxiety group having higher PCL-C scores than the low trait anxiety group (p anxiety had less tachycardia in response to acute psychological stress than those with lower trait anxiety. The present results point to a higher risk for more anxious individuals of a maladaptive reaction to stressful events.

  1. Ecophysiological and antioxidant traits of Salvia officinalis under ozone stress.

    Science.gov (United States)

    Pellegrini, Elisa; Francini, Alessandra; Lorenzini, Giacomo; Nali, Cristina

    2015-09-01

    Ecophysiological and antioxidant traits were evaluated in sage (Salvia officinalis) plants exposed to 120 ppb of ozone for 90 consecutive days (5 h day(-1)). At the end of fumigation, plants showed slight leaf yellowing that could be considered the first visual symptom of leaf senescence. Ozone-stressed leaves showed (1) reduced photosynthetic activity (-70 % at the end of exposure), (2) chlorophyll loss (-59 and -56 % of chlorophyll a and b concentrations, starting from 30 days from the beginning of exposure), and (3) cellular water deficit (-12 % of the relative water content at the end of the fumigation). These phenomena are indicative of oxidative stress in the chloroplasts (as confirmed by the strong degradation of β-carotene) despite the photoprotection conferred by xanthophyll cycle [as demonstrated by the significant rise of de-epoxidation index, reaching the maximum value at the end of the treatment (+69 %)], antioxidant compounds [as confirmed by the increase of phenols (in particular caffeic acid and rosmarinic acid)], and water-soluble carbohydrates (especially monosaccharides). By means of combined ecophysiological and biochemical approaches, this study demonstrates that S. officinalis is able to activate an adaptive survival mechanism allowing the plant to complete its life cycle even under oxidative stressful conditions.

  2. ESTIMATION OF INCREASE OF STRESS RESISTANCE AMONG STUDENTS

    OpenAIRE

    Drobysheva O. M.

    2015-01-01

    By results of the estimation of stress resistance on dynamics of the regulation-adaptive status we can observe, that the autogenic training at the end of one academic year did not cause authentic changes in stress resistance in students with high and low levels of stress resistance. At the same time, it raised stress resistance for persons with a moderate level of stress resistance

  3. Identifying the role of different personality traits on the relationship between stress and food choice

    OpenAIRE

    Trew, Marissa

    2014-01-01

    Research shows that high levels of stress correlate with higher consumption of high- fat and high-sugar snack-type foods, particularly amongst women. However, it has been observed that not all individuals are vulnerable to this pattern of ‘stress-related’ eating. Both stress and dietary habits have been strongly correlated with specific personality traits but previous research has neglected to observe whether personality traits significantly affect correlations between perceived stress and ty...

  4. Plastic responses to four environmental stresses and cross-resistance in a laboratory population of Drosophila melanogaster

    DEFF Research Database (Denmark)

    Bubliy, Oleg A; Kristensen, Torsten Nygård; Kellermann, Vanessa

    2012-01-01

    be delayed. 5. The pattern of acclimation ⁄ hardening responses considered in the context of literature data on stress resistance indicates that expression of heat-shock proteins is not likely to contribute to the observed cross-resistance, but other probable general stress resistance mechanisms......1. Acclimation or hardening to one stress in arthropods can lead to a plastic response, which confers increased resistance to other stresses. Such cross-resistance may indicate shared physiological resistance mechanisms and a possibility of joint evolution for resistance traits. 2. In this study......, we tested for cross-resistance using Drosophila melanogaster as a model system.Adult females were assayed for resistance to cold, heat, desiccation and starvation following cold acclimation, heat hardening, desiccation hardening and starvation acclimation, resulting in 12 pretreatment...

  5. Quantitative trait loci for resistance to maize streak virus disease in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-18

    Jul 18, 2008 ... characterized quantitative trait loci affecting resistance to maize streak virus in maize populations of S4 families from the cross of one resistant MAL13 and one susceptible MAL9 recombinant inbred lines. Resistance was evaluated in replicated field trials under artificial inoculation while selecting using.

  6. Quantitative trait loci for resistance to maize streak virus disease in ...

    African Journals Online (AJOL)

    Maize streak virus disease is an important disease of maize in Kenya. In this study, we mapped and characterized quantitative trait loci affecting resistance to maize streak virus in maize populations of S4 families from the cross of one resistant MAL13 and one susceptible MAL9 recombinant inbred lines. Resistance was ...

  7. Fluctuating asymmetry and environmental stress: understanding the role of trait history.

    Directory of Open Access Journals (Sweden)

    Greet De Coster

    Full Text Available While fluctuating asymmetry (FA; small, random deviations from perfect symmetry in bilaterally symmetrical traits is widely regarded as a proxy for environmental and genetic stress effects, empirical associations between FA and stress are often weak or heterogeneous among traits. A conceptually important source of heterogeneity in relationships with FA is variation in the selection history of the trait(s under study, i.e. traits that experienced a (recent history of directional change are predicted to be developmentally less stable, potentially through the loss of canalizing modifiers. Here we applied X-ray photography on museum specimens and live captures to test to what extent the magnitude of FA and FA-stress relationships covary with directional shifts in traits related to the flight apparatus of four East-African rainforest birds that underwent recent shifts in habitat quality and landscape connectivity. Both the magnitude and direction of phenotypic change varied among species, with some traits increasing in size while others decreased or maintained their original size. In three of the four species, traits that underwent larger directional changes were less strongly buffered against random perturbations during their development, and traits that increased in size over time developed more asymmetrically than those that decreased. As we believe that spurious relationships due to biased comparisons of historic (museum specimens and current (field captures samples can be ruled out, these results support the largely untested hypothesis that directional shifts may increase the sensitivity of developing traits to random perturbations of environmental or genetic origin.

  8. Plant defense against herbivorous pests: exploiting resistance and tolerance traits for sustainable crop protection

    Directory of Open Access Journals (Sweden)

    Carolyn Mitchell

    2016-07-01

    Full Text Available Interactions between plants and insect herbivores are important determinants of plant productivity in managed and natural vegetation. In response to attack, plants have evolved a range of defenses to reduce the threat of injury and loss of productivity. Crop losses from damage caused by arthropod pests can exceed 15% annually. Crop domestication and selection for improved yield and quality can alter the defensive capability of the crop, increasing reliance on artificial crop protection. Sustainable agriculture, however, depends on reduced chemical inputs. There is an urgent need, therefore, to identify plant defensive traits for crop improvement. Plant defense can be divided into resistance and tolerance strategies. Plant traits that confer herbivore resistance typically prevent or reduce herbivore damage through expression of traits that deter pests from settling, attaching to surfaces, feeding and reproducing, or that reduce palatability. Plant tolerance of herbivory involves expression of traits that limit the negative impact of herbivore damage on productivity and yield. Identifying the defensive traits expressed by plants to deter herbivores or limit herbivore damage, and understanding the underlying defense mechanisms, is crucial for crop scientists to exploit plant defensive traits in crop breeding. In this review, we assess the traits and mechanisms underpinning herbivore resistance and tolerance, and conclude that physical defense traits, plant vigor and herbivore-induced plant volatiles show considerable utility in pest control, along with mixed species crops. We highlight emerging approaches for accelerating the identification of plant defensive traits and facilitating their deployment to improve the future sustainability of crop protection.

  9. Changes in fitness-associated traits due to the stacking of transgenic glyphosate resistance and insect resistance in Brassica napus L.

    Science.gov (United States)

    Londo, J P; Bollman, M A; Sagers, C L; Lee, E H; Watrud, L S

    2011-01-01

    Increasingly, genetically modified crops are being developed to express multiple ‘stacked' traits for different types of transgenes, for example, herbicide resistance, insect resistance, crop quality and tolerance to environmental stresses. The release of crops that express multiple traits could result in ecological changes in weedy environments if feral crop plants or hybrids formed with compatible weeds results in more competitive plants outside of agriculture. To examine the effects of combining transgenes, we developed a stacked line of canola (Brassica napus L.) from a segregating F2 population that expresses both transgenic glyphosate resistance (CP4 EPSPS) and lepidopteran insect resistance (Cry1Ac). Fitness-associated traits were evaluated between this stacked genotype and five other Brassica genotypes in constructed mesocosm plant communities exposed to insect herbivores (Plutella xylostella L.) or glyphosate-drift. Vegetative biomass, seed production and relative fecundity were all reduced in stacked trait plants when compared with non-transgenic plants in control treatments, indicating potential costs of expressing multiple transgenes without selection pressure. Although costs of the transgenes were offset by selective treatment, the stacked genotype continued to produce fewer seeds than either single transgenic line. However, the increase in fitness of the stacked genotype under selective pressure contributed to an increased number of seeds within the mesocosm community carrying unselected, hitchhiking transgenes. These results demonstrate that the stacking of these transgenes in canola results in fitness costs and benefits that are dependent on the type and strength of selection pressure, and could also contribute to changes in plant communities through hitchhiking of unselected traits. PMID:21427753

  10. Quantitative trait loci for yield and morphological traits in maize under drought stress

    Directory of Open Access Journals (Sweden)

    Nikolić Ana

    2011-01-01

    Full Text Available Drought is one of the most important factors contributing to crop yield loss. In order to develop maize varieties with drought tolerance, it is necessary to explore the genetic basis. Mapping quantitative trait loci (QTL that control the yield and associate agronomic traits is one way of understanding drought genetics. QTLs associated with grain yield (GY, leaf width (LW3, LW4 plant height (PH, ear height (EH, leaf number (NL, tassel branch number (TBN and tassel length (TL were studied with composite interval mapping. A total of 43 QTLs were detected, distributed on all chromosomes, except chromosome 9. Phenotypic variability determined for the identified QTLs for all the traits was in the range from 20.99 to 87.24%. Mapping analysis identified genomic regions associated with two traits in a manner that was consistent with phenotypic correlation among traits, supporting either pleiotropy or tight linkage among QTLs.

  11. Association of Trait Resilience With Peritraumatic and Posttraumatic Stress in Patients With Myocardial Infarction.

    Science.gov (United States)

    Meister, Rebecca Elisabeth; Princip, Mary; Schnyder, Ulrich; Barth, Jürgen; Znoj, Hansjörg; Schmid, Jean-Paul; Wittmann, Lutz; von Känel, Roland

    2016-04-01

    Acute myocardial infarction (MI) is a life-threatening condition, leading to immediate fear and distress in many patients. Approximately 18% of patients develop posttraumatic stress disorder in the aftermath of MI. Trait resilience has shown to be a protective factor for the development of posttraumatic stress disorder. However, whether this buffering effect has already an impact on peritraumatic distress and applies to patients with MI is elusive. We investigated 98 consecutive patients with acute MI within 48 hours after having reached stable circulatory conditions and 3 months thereafter. Peritraumatic distress was assessed retrospectively with three single-item questions about pain, fear, and helplessness during MI. All patients completed the Posttraumatic Diagnostic Scale (PDS) and the Resilience Scale to self-rate posttraumatic stress and trait resilience. Multivariate models adjusting for sociodemographic and medical factors showed that trait resilience was not associated with peritraumatic distress, but significantly so with posttraumatic stress. Patients with greater trait resilience showed lower PDS scores (b = -0.06, p resilience did not emerge as a moderator of this relationship. The findings suggest that trait resilience does not buffer the perception of acute MI as stressful per se but may enhance better coping with the traumatic experience in the longer term, thus preventing the development of MI-associated posttraumatic stress. Trait resilience may play an important role in posttraumatic stress symptoms triggered by medical diseases such as acute MI.

  12. The association of personality traits and coping styles according to stress level.

    Science.gov (United States)

    Afshar, Hamid; Roohafza, Hamid Reza; Keshteli, Ammar Hassanzadeh; Mazaheri, Mina; Feizi, Awat; Adibi, Peyman

    2015-04-01

    Some personality traits and coping styles could be as risk factors in stressful situations. This study aimed to investigate the association of personality traits and coping styles according to the stress level. This cross-sectional study was performed in 2011. A total of 4628 individuals over 20 years were selected by random sampling from nonacademic employees that working in 50 different centers across Isfahan province. Data were collected using 12-item General Health Questionnaire (GHQ-12), Big Five Personality Inventory Short Form and coping strategies scale, and individuals were divided into high and low-stress groups in term of GHQ-12. To analyze the data, a binary logistic regression analysis was conducted. Mean age of participants was 36.3 ± 7.91 years and 56.26% (2604) of them were female. Neuroticism with adjusting covariates of demographic characteristics and the rest of personality traits was a risk factor for stress level with odds ratios (OR) OR:1.24; but other personality traits were protective. Also, active coping styles were protective factors for OR of stress level with adjusting covariates of demographic characteristics and the rest of coping styles, and positive reinterpretation and growth was the most effective of coping style with OR:0.84. Some personality traits are associated with passive copings and cause high-stress level. So, it could be concluded that improve and strengthen effective coping strategies in individual with maladaptive traits should be considered as a crucial component of prevention and control programs of stress.

  13. Trait Resilience Moderates the Longitudinal Linkage between Adolescent Posttraumatic Stress Disorder Symptoms and Posttraumatic Growth

    Science.gov (United States)

    Ying, Liuhua; Wang, Yanli; Lin, Chongde; Chen, Chuansheng

    2016-01-01

    The current study examined the longitudinal association between posttraumatic stress disorder (PTSD) symptoms and posttraumatic growth (PTG) as well as the moderating role of trait resilience in that association. Participants completed measures of PTSD symptoms, PTG, and trait resilience at 12, 18, and 24 months after the Wenchuan earthquake.…

  14. Oxidative stress resistance in Porphyromonas gingivalis

    Science.gov (United States)

    Henry, Leroy G; McKenzie, Rachelle ME; Robles, Antonette; Fletcher, Hansel M

    2012-01-01

    Porphyromonas gingivalis, a black-pigmented, Gram-negative anaerobe, is an important etiologic agent of periodontal disease. The harsh inflammatory condition of the periodontal pocket implies that this organism has properties that will facilitate its ability to respond and adapt to oxidative stress. Because the stress response in the pathogen is a major determinant of its virulence, a comprehensive understanding of its oxidative stress resistance strategy is vital. We discuss multiple mechanisms and systems that clearly work in synergy to defend and protect P. gingivalis against oxidative damage caused by reactive oxygen species. The involvement of multiple hypothetical proteins and/or proteins of unknown function in this process may imply other unique mechanisms and potential therapeutic targets. PMID:22439726

  15. Genome-wide association analysis of oxidative stress resistance in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Allison L Weber

    Full Text Available Aerobic organisms are susceptible to damage by reactive oxygen species. Oxidative stress resistance is a quantitative trait with population variation attributable to the interplay between genetic and environmental factors. Drosophila melanogaster provides an ideal system to study the genetics of variation for resistance to oxidative stress.We used 167 wild-derived inbred lines of the Drosophila Genetic Reference Panel for a genome-wide association study of acute oxidative stress resistance to two oxidizing agents, paraquat and menadione sodium bisulfite. We found significant genetic variation for both stressors. Single nucleotide polymorphisms (SNPs associated with variation in oxidative stress resistance were often sex-specific and agent-dependent, with a small subset common for both sexes or treatments. Associated SNPs had moderately large effects, with an inverse relationship between effect size and allele frequency. Linear models with up to 12 SNPs explained 67-79% and 56-66% of the phenotypic variance for resistance to paraquat and menadione sodium bisulfite, respectively. Many genes implicated were novel with no known role in oxidative stress resistance. Bioinformatics analyses revealed a cellular network comprising DNA metabolism and neuronal development, consistent with targets of oxidative stress-inducing agents. We confirmed associations of seven candidate genes associated with natural variation in oxidative stress resistance through mutational analysis.We identified novel candidate genes associated with variation in resistance to oxidative stress that have context-dependent effects. These results form the basis for future translational studies to identify oxidative stress susceptibility/resistance genes that are evolutionary conserved and might play a role in human disease.

  16. Cancer resistance as an acquired and inheritable trait

    DEFF Research Database (Denmark)

    Koch, Janne; Hau, Jann; Jensen, Henrik Elvang

    2014-01-01

    AIM: To induce cancer resistance in wild-type mice and detect if the resistance could be inherited to the progeny of the induced resistant mice. Furthermore to investigate the spectrum and immunology of this inherited cancer resistance. MATERIALS AND METHODS: Resistance to with live S180 cancer c...... of the resistance is unknown but may involve epigenetic mechanisms. Other examples of inheritability of acquired phenotypic changes exist but, to our knowledge, this is the first demonstration of acquired, inherited cancer resistance.......AIM: To induce cancer resistance in wild-type mice and detect if the resistance could be inherited to the progeny of the induced resistant mice. Furthermore to investigate the spectrum and immunology of this inherited cancer resistance. MATERIALS AND METHODS: Resistance to with live S180 cancer...... cells in BALB/c mice was induced by immunization with inactivated S180 cancer cells. The immunization was performed by either frozen/thawed or irradiated cancer cells or cell-free ascitic fluid (CFAF). RESULTS: In all instances the induced resistance was demonstrated to be inheritable. The phenotype...

  17. Maize water status and physiological traits as affected by root endophytic fungus Piriformospora indica under combined drought and mechanical stresses.

    Science.gov (United States)

    Hosseini, Fatemeh; Mosaddeghi, Mohammad Reza; Dexter, Anthony Roger; Sepehri, Mozhgan

    2018-02-16

    Under combined drought and mechanical stresses, mechanical stress primarily controlled physiological responses of maize. Piriformospora indica mitigated the adverse effects of stresses, and inoculated maize experienced less oxidative damage and had better adaptation to stressful conditions. The objective of this study was to investigate the effect of maize root colonization by an endophytic fungus P. indica on plant water status, physiological traits and root morphology under combined drought and mechanical stresses. Seedlings of inoculated and non-inoculated maize (Zea mays L., cv. single cross 704) were cultivated in growth chambers filled with moistened siliceous sand at a matric suction of 20 hPa. Drought stress was induced using PEG 6000 solution with osmotic potentials of 0, - 0.3 and - 0.5 MPa. Mechanical stress (i.e., penetration resistances of 1.05, 4.23 and 6.34 MPa) was exerted by placing weights on the surface of the sand medium. After 30 days, leaf water potential (LWP) and relative water content (RWC), root and shoot fresh weights, root volume (RV) and diameter (RD), leaf proline content, leaf area (LA) and catalase (CAT) and ascorbate peroxidase (APX) activities were measured. The results show that exposure to individual drought and mechanical stresses led to higher RD and proline content and lower plant biomass, RV and LA. Moreover, increasing drought and mechanical stress severity increased APX activity by about 1.9- and 3.1-fold compared with the control. When plants were exposed to combined stresses, mechanical stress played the dominant role in controlling plant responses. P. indica-inoculated plants are better adapted to individual and combined stresses. The inoculated plants had greater RV, LA, RWC, LWP and proline content under stressful conditions. In comparison with non-inoculated plants, inoculated plants showed lower CAT and APX activities which means that they experienced less oxidative stress induced by stressful conditions.

  18. Oxidative Stress Resistance in Deinococcus radiodurans†

    Science.gov (United States)

    Slade, Dea; Radman, Miroslav

    2011-01-01

    Summary: Deinococcus radiodurans is a robust bacterium best known for its capacity to repair massive DNA damage efficiently and accurately. It is extremely resistant to many DNA-damaging agents, including ionizing radiation and UV radiation (100 to 295 nm), desiccation, and mitomycin C, which induce oxidative damage not only to DNA but also to all cellular macromolecules via the production of reactive oxygen species. The extreme resilience of D. radiodurans to oxidative stress is imparted synergistically by an efficient protection of proteins against oxidative stress and an efficient DNA repair mechanism, enhanced by functional redundancies in both systems. D. radiodurans assets for the prevention of and recovery from oxidative stress are extensively reviewed here. Radiation- and desiccation-resistant bacteria such as D. radiodurans have substantially lower protein oxidation levels than do sensitive bacteria but have similar yields of DNA double-strand breaks. These findings challenge the concept of DNA as the primary target of radiation toxicity while advancing protein damage, and the protection of proteins against oxidative damage, as a new paradigm of radiation toxicity and survival. The protection of DNA repair and other proteins against oxidative damage is imparted by enzymatic and nonenzymatic antioxidant defense systems dominated by divalent manganese complexes. Given that oxidative stress caused by the accumulation of reactive oxygen species is associated with aging and cancer, a comprehensive outlook on D. radiodurans strategies of combating oxidative stress may open new avenues for antiaging and anticancer treatments. The study of the antioxidation protection in D. radiodurans is therefore of considerable potential interest for medicine and public health. PMID:21372322

  19. Oxidative stress resistance in Deinococcus radiodurans.

    Science.gov (United States)

    Slade, Dea; Radman, Miroslav

    2011-03-01

    Deinococcus radiodurans is a robust bacterium best known for its capacity to repair massive DNA damage efficiently and accurately. It is extremely resistant to many DNA-damaging agents, including ionizing radiation and UV radiation (100 to 295 nm), desiccation, and mitomycin C, which induce oxidative damage not only to DNA but also to all cellular macromolecules via the production of reactive oxygen species. The extreme resilience of D. radiodurans to oxidative stress is imparted synergistically by an efficient protection of proteins against oxidative stress and an efficient DNA repair mechanism, enhanced by functional redundancies in both systems. D. radiodurans assets for the prevention of and recovery from oxidative stress are extensively reviewed here. Radiation- and desiccation-resistant bacteria such as D. radiodurans have substantially lower protein oxidation levels than do sensitive bacteria but have similar yields of DNA double-strand breaks. These findings challenge the concept of DNA as the primary target of radiation toxicity while advancing protein damage, and the protection of proteins against oxidative damage, as a new paradigm of radiation toxicity and survival. The protection of DNA repair and other proteins against oxidative damage is imparted by enzymatic and nonenzymatic antioxidant defense systems dominated by divalent manganese complexes. Given that oxidative stress caused by the accumulation of reactive oxygen species is associated with aging and cancer, a comprehensive outlook on D. radiodurans strategies of combating oxidative stress may open new avenues for antiaging and anticancer treatments. The study of the antioxidation protection in D. radiodurans is therefore of considerable potential interest for medicine and public health.

  20. Personality traits and types predict medical school stress: a six-year longitudinal and nationwide study.

    Science.gov (United States)

    Tyssen, Reidar; Dolatowski, Filip C; Røvik, Jan Ole; Thorkildsen, Ruth F; Ekeberg, Oivind; Hem, Erlend; Gude, Tore; Grønvold, Nina T; Vaglum, Per

    2007-08-01

    Personality types (combinations of traits) that take into account the interplay between traits give a more detailed picture of an individual's character than do single traits. This study examines whether both personality types and traits predict stress during medical school training. We surveyed Norwegian medical students (n = 421) 1 month after they began medical school (T1), at the mid-point of undergraduate Year 3 (T2), and at the end of undergraduate Year 6 (T3). A total of 236 medical students (56%) responded at all time-points. They were categorised according to Torgersen's personality typology by their combination of high and low scores on the 'Big Three' personality traits of extroversion, neuroticism and conscientiousness. We studied the effects of both personality types (spectator, insecure, sceptic, brooder, hedonist, impulsive, entrepreneur and complicated) and traits on stress during medical school. There was a higher level of stress among female students. The traits of neuroticism (P = 0.002) and conscientiousness (P = 0.03) were independent predictors of stress, whereas female gender was absorbed by neuroticism in the multivariate model. When controlled for age and gender, 'brooders' (low extroversion, high neuroticism, high conscientiousness) were at risk of experiencing more stress (P = 0.02), whereas 'hedonists' (high extroversion, low neuroticism, low conscientiousness) were more protected against stress (P = 0.001). This is the first study to show that a specific combination of personality traits can predict medical school stress. The combination of high neuroticism and high conscientiousness is considered to be particularly high risk.

  1. Effects of trait anxiety and situational stress on attentional shifting are buffered by working memory capacity.

    Science.gov (United States)

    Edwards, Mark S; Moore, Philippa; Champion, James C; Edwards, Elizabeth J

    2015-01-01

    Attentional Control Theory (ACT) predicts that trait anxiety and situation stress combine to reduce performance efficiency on tasks requiring rapid shifts in attention. Recent evidence has also suggested that working memory capacity (WMC) might moderate this relationship. We controlled for methodological difficulties in the existing literature to investigate the relationships between trait anxiety, situational stress, and WMC on attentional shifting. Seventy undergraduate students participated in the study. Trait anxiety was operationalized using questionnaire scores, situational stress was manipulated through a pressured counting task, and WMC was based on performance on the Automated Operation Span Task (AOSPAN). The shifting task involved a modified version of the Sternberg paradigm as the primary task and an oddball tone-discrimination task as the secondary task. Dependent variables were performance effectiveness (accuracy) and processing efficiency (accuracy divided by response time) on the secondary task. There was no effect of anxiety, stress, or WMC in predicting performance effectiveness; however, a significant three-way interaction on processing efficiency was observed. At higher WMC, anxiety and situational stress were not associated with processing efficiency. Conversely, at lower WMC, higher trait anxiety was associated with poorer efficiency but only for those who reported higher situational stress; for those who reported lower situational stress higher trait anxiety predicted facilitated efficiency. Results are interpreted with respect to ACT and directions for future research are discussed.

  2. Individual differences in early adolescents' latent trait cortisol (LTC): Relation to recent acute and chronic stress.

    Science.gov (United States)

    Stroud, Catherine B; Chen, Frances R; Doane, Leah D; Granger, Douglas A

    2016-08-01

    Research suggests that environmental stress contributes to health by altering the regulation of the hypothalamic pituitary adrenal (HPA) axis. Recent evidence indicates that early life stress alters trait indicators of HPA axis activity, but whether recent stress alters such indicators is unknown. Using objective contextual stress interviews with adolescent girls and their mothers, we examined the impact of recent acute and chronic stress occurring during the past year on early adolescent girls' latent trait cortisol (LTC) level. We also examined whether associations between recent stress and LTC level: a) varied according to the interpersonal nature and controllability of the stress; and b) remained after accounting for the effect of early life stress. Adolescents (n=117;M age=12.39years) provided salivary cortisol samples three times a day (waking, 30min post-waking and bedtime) over 3days. Results indicated that greater recent interpersonal acute stress and greater recent independent (i.e., uncontrollable) acute stress were each associated with a higher LTC level, over and above the effect of early adversity. In contrast, greater recent chronic stress was associated with a lower LTC level. Findings were similar in the overall sample and a subsample of participants who strictly adhered to the timed schedule of saliva sample collection. Implications for understanding the impact of recent stress on trait-like individual differences in HPA axis activity are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. ADULT ANXIETY DISORDERS IN RELATION TO TRAIT ANXIETY AND PERCEIVED STRESS IN CHILDHOOD.

    Science.gov (United States)

    Mundy, Elizabeth A; Weber, Mareen; Rauch, Scott L; Killgore, William D S; Simon, Naomi M; Pollack, Mark H; Rosso, Isabelle M

    2015-10-01

    It is well established that objective early life stressors increase risk for anxiety disorders and that environmental stressors interact with dispositional factors such as trait anxiety. There is less information on how subjective perception of stress during childhood relates to later clinical anxiety. This study tested whether childhood perceived stress and trait anxiety were independently and interactively associated with adult anxiety disorders. Forty-seven adults diagnosed with anxiety disorders (M age = 34 yr., SD = 11) and 29 healthy participants (M = 33 yr., SD = 13) completed the adult Perceived Stress Scale, the State-Trait Anxiety Inventory, and the Global Perceived Early Life Events Scale as a measure of perceived stress during childhood. In a logistic regression model, high childhood perceived stress (β = 0.64) and trait anxiety (β = 0.11) were associated with significantly greater odds of adult anxiety disorder. The association between childhood perceived stress and adult anxiety remained significant when controlling for adult perceived stress. These findings suggest that children's perception of stress in their daily lives may be an important target of intervention to prevent the progression of stress into clinically significant anxiety.

  4. Cognitive trait anxiety, situational stress, and mental effort predict shifting efficiency: Implications for attentional control theory.

    Science.gov (United States)

    Edwards, Elizabeth J; Edwards, Mark S; Lyvers, Michael

    2015-06-01

    Attentional control theory (ACT) predicts that trait anxiety and situational stress interact to impair performance on tasks that involve attentional shifting. The theory suggests that anxious individuals recruit additional effort to prevent shortfalls in performance effectiveness (accuracy), with deficits becoming evident in processing efficiency (the relationship between accuracy and time taken to perform the task). These assumptions, however, have not been systematically tested. The relationship between cognitive trait anxiety, situational stress, and mental effort in a shifting task (Wisconsin Card Sorting Task) was investigated in 90 participants. Cognitive trait anxiety was operationalized using questionnaire scores, situational stress was manipulated through ego threat instructions, and mental effort was measured using a visual analogue scale. Dependent variables were performance effectiveness (an inverse proportion of perseverative errors) and processing efficiency (an inverse proportion of perseverative errors divided by response time on perseverative error trials). The predictors were not associated with performance effectiveness; however, we observed a significant 3-way interaction on processing efficiency. At higher mental effort (+1 SD), higher cognitive trait anxiety was associated with poorer efficiency independently of situational stress, whereas at lower effort (-1 SD), this relationship was highly significant and most pronounced for those in the high-stress condition. These results are important because they provide the first systematic test of the relationship between trait anxiety, situational stress, and mental effort on shifting performance. The data are also consistent with the notion that effort moderates the relationship between anxiety and shifting efficiency, but not effectiveness. (c) 2015 APA, all rights reserved).

  5. Relationships among Stress Coping, Secure Attachment, and the Trait of Resilience among Taiwanese College Students

    Science.gov (United States)

    Li, Ming-hui

    2008-01-01

    College students often live stressful lives, yet some college students appear to adapt better than their peers in similar situations. Active coping appears to be a vital factor that contributes to a successful adaptation. This study explored relative effectiveness among stress, secure attachment, and the trait of resilience in predicting active…

  6. Predicting the response of aquatic invertebrates to stress using species traits and stressor mode of action

    NARCIS (Netherlands)

    Rubach, M.N.

    2010-01-01

    How much stress can one take? It depends, on the combination of your mental and physical characteristics (traits), but it’s hard to predict. Chemicals can have devastating effects on ecosystems and they can cause stress in animals and plants. Thus, their risk for ecosystem health needs to be

  7. 40 CFR 90.427 - Catalyst thermal stress resistance evaluation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Catalyst thermal stress resistance... Gaseous Exhaust Test Procedures § 90.427 Catalyst thermal stress resistance evaluation. (a) The purpose of... catalyst conversion efficiency for Phase 1 engines. The thermal stress is imposed on the test catalyst by...

  8. 40 CFR 91.427 - Catalyst thermal stress resistance evaluation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Catalyst thermal stress resistance... Procedures § 91.427 Catalyst thermal stress resistance evaluation. (a)(1) The purpose of the evaluation procedure specified in this section is to determine the effect of thermal stress on catalyst conversion...

  9. Comprehensive Screening of Some West and Central African Sesame Genotypes for Drought Resistance Probing by Agromorphological, Physiological, Biochemical and Seed Quality Traits

    Directory of Open Access Journals (Sweden)

    Komivi Dossa

    2017-12-01

    Full Text Available Sesame is an important crop in West and Central Africa playing a role of an alternative cash crop for smallholders. However, sesame productivity is highly impaired by drought. This study aimed at identifying some drought-resistant genotypes and efficient screening traits in large sesame germplasm. Ten genotypes were examined based on 21 biochemical, physiological, agromorphological and seed quality traits under three weeks of water stress. A high variability for drought resistance was observed among the genotypes. The genotypes WC17, WC18 and WC14 were drought resistant, WC12, WC13, WC06 and WC03 were moderately drought resistant while, WC02, WC10 and WC08 were drought sensitive, based on principal component analysis. The resistant genotypes exhibited both avoidance and tolerance features including increase of the root system, reduced water loss, highest activity of antioxidative enzymes and accumulation of proline. They produced higher biomass and had higher ability to maintain seed quality under drought stress compared with the sensitive genotypes. Strong accumulation (~200% ratio stress/control of biochemical markers including superoxide dismutase, ascorbate peroxidase, catalase and proline could be regarded as an important indicator for selecting drought resistant genotypes. This study represents a reference for future research towards developing new varieties with improved drought resistance in West and Central Africa.

  10. Blunted cardiac reactivity to psychological stress associated with higher trait anxiety: a study in peacekeepers

    OpenAIRE

    de Souza, Gabriela Guerra Leal; Mendon?a-de-Souza, Ana Carolina Ferraz; Duarte, Ant?nio Fernando Ara?jo; Fischer, Nastassja Lopes; Souza, Wanderson Fernandes de; Silva Freire Coutinho, Evandro; Figueira, Ivan; Volchan,Eliane

    2015-01-01

    Background Both exaggerated and diminished reactivity to stress can be maladaptive. Previous studies have shown that performing increasingly difficult tasks leads first to increased reactivity and then to a blunted response when success is impossible. Our aim was to investigate the influence of trait anxiety on cardiac and cortisol response to and recovery from a standardized psychosocial stress task (Trier Social Stress Task) in a homogeneous sample of healthy peacekeepers. We hypothesized t...

  11. Increasing correlations between personality traits and cortisol stress responses obtained by data aggregation.

    Science.gov (United States)

    Pruessner, J C; Gaab, J; Hellhammer, D H; Lintz, D; Schommer, N; Kirschbaum, C

    1997-11-01

    Attempts to link personality traits and cortisol stress responses have often been inconclusive. The aim of this paper was to investigate this association by aggregating cortisol stress responses. Therefore, 20 healthy men were exposed to a task consisting of public speaking and mental arithmetics in front of an audience on five days. Six cortisol levels were measured in relation to the stressful task obtained at 10-min intervals on each day. Psychological assessment included the Questionnaire for Competence and Control (FKK) and the Giessen-Test (G-T). These questionnaires focus on assessing personality traits, i.e. locus of control and self-concept. Areas under the response curve (AUC) of the six cortisol samples were computed to obtain an index of the individual's cortisol stress response on each day. Since novelty is a random situational factor likely to mask individual differences in the stress response, the AUC cortisol stress responses of days two to five were consecutively aggregated, excluding the first day. Scales of the two questionnaires employed did not correlate with the AUC cortisol stress response of the first stress trial. The correlation pattern of the AUC cortisol measures of days two to five with the questionnaire scales was inconclusive. However, significant correlations emerged with an increasing number of cortisol stress responses aggregated. Correlations between the measure of social dominance and aggregated AUC cortisol stress responses rose from r = -.47 on day two of the experimental session to r = -.70 after aggregating days two to five. Similarly, measures of locus of control and cortisol stress responses became increasingly correlated with aggregation of several stress exposures. These data provide preliminary evidence for a relationship between questionnaire scales aiming at assessing personality traits and cortisol stress responses uncovered by repeated stress exposure and data aggregation. While novelty may mask the impact of

  12. Development of abiotic-stress resistant warm season trufgrasses by proton-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Y. W.; Kim, J. Y.; Jeong, S. H. [Korea Univ., Seoul (Korea, Republic of)

    2007-04-15

    The direct use of mutation is a valuable approach to generate genetic variation in crop species by altering agronomically useful major traits. The proton beam, as a mutagen, was applied to improve resistance traits of Zoysia grass under various abiotic stresses. Proton beam was irradiated to mature dry seeds of Zenith (Zoysia grass), which is well-adapted to Korean climate, using a proton- accelerator with seven different doses (50, 100, 150, 200, 250, 300, 400 Gy). Individual seedling of M1 plant was transplanted from the seed bed and allowed to reach appropriate plant mass. Clones that showed superior growth were chosen and transplanted to pots for further clone propagation and field evaluation. Growth characteristics of turfgrass, such as plant height, leaf length, leaf width, number of tiller were evaluated ninety days after sowing. Although large variation within each dose, noticeable differences were found among different irradiated doses. Most of the mutant clones derived from the irradiation treatment showed more vigorous growth than the control plants. RAPD (Random Amplified Polymorphic DNA) and AFLP (Amplified Fragment Length Polymorphism) methods were conducted to analyze genomic variations associated with proton beam irradiation. In order to establish selection criteria for selection of salt-stress resistance plants, an in vitro method that is able to select salt-stress resistant mutants in liquid media without ambient disturbances. Total 647 predominance clones that were considered as abiotic stress resistant mutants were transplanted to the field for further evaluation.

  13. Characterizing drought stress and trait influence on maize yield under current and future conditions.

    Science.gov (United States)

    Harrison, Matthew T; Tardieu, François; Dong, Zhanshan; Messina, Carlos D; Hammer, Graeme L

    2014-03-01

    Global climate change is predicted to increase temperatures, alter geographical patterns of rainfall and increase the frequency of extreme climatic events. Such changes are likely to alter the timing and magnitude of drought stresses experienced by crops. This study used new developments in the classification of crop water stress to first characterize the typology and frequency of drought-stress patterns experienced by European maize crops and their associated distributions of grain yield, and second determine the influence of the breeding traits anthesis-silking synchrony, maturity and kernel number on yield in different drought-stress scenarios, under current and future climates. Under historical conditions, a low-stress scenario occurred most frequently (ca. 40%), and three other stress types exposing crops to late-season stresses each occurred in ca. 20% of cases. A key revelation shown was that the four patterns will also be the most dominant stress patterns under 2050 conditions. Future frequencies of low drought stress were reduced by ca. 15%, and those of severe water deficit during grain filling increased from 18% to 25%. Despite this, effects of elevated CO2 on crop growth moderated detrimental effects of climate change on yield. Increasing anthesis-silking synchrony had the greatest effect on yield in low drought-stress seasonal patterns, whereas earlier maturity had the greatest effect in crops exposed to severe early-terminal drought stress. Segregating drought-stress patterns into key groups allowed greater insight into the effects of trait perturbation on crop yield under different weather conditions. We demonstrate that for crops exposed to the same drought-stress pattern, trait perturbation under current climates will have a similar impact on yield as that expected in future, even though the frequencies of severe drought stress will increase in future. These results have important ramifications for breeding of maize and have implications for

  14. Inbreeding-related trade-offs in stress resistance in the ant Formica exsecta.

    Science.gov (United States)

    Freitak, D; Bos, N; Stucki, D; Sundström, L

    2014-11-01

    Inbred individuals and populations are predicted to suffer from inbreeding depression, especially in times of stress. Under natural conditions, organisms are exposed to more than one stressor at any one time, highlighting the importance of stress resistance traits. We studied how inbreeding- and immunity-related traits are correlated under different dietary conditions in the ant Formica exsecta. Its natural diet varies in the amount and nature of plant secondary compounds and the level of free radicals, all of which require detoxification to maintain organismal homeostasis. We found that inbreeding decreased general antibacterial activity under dietary stress, suggesting inbreeding-related physiological trade-offs. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  15. The association of personality traits and coping styles according to stress level

    Directory of Open Access Journals (Sweden)

    Hamid Afshar

    2015-01-01

    Full Text Available Background: Some personality traits and coping styles could be as risk factors in stressful situations. This study aimed to investigate the association of personality traits and coping styles according to the stress level. Meterials and Methods: This cross-sectional study was performed in 2011. A total of 4628 individuals over 20 years were selected by random sampling from nonacademic employees that working in 50 different centers across Isfahan province. Data were collected using 12-item General Health Questionnaire (GHQ-12, Big Five Personality Inventory Short Form and coping strategies scale, and individuals were divided into high and low-stress groups in term of GHQ-12. To analyze the data, a binary logistic regression analysis was conducted. Results: Mean age of participants was 36.3 ± 7.91 years and 56.26% (2604 of them were female. Neuroticism with adjusting covariates of demographic characteristics and the rest of personality traits was a risk factor for stress level with odds ratios (OR OR:1.24; but other personality traits were protective. Also, active coping styles were protective factors for OR of stress level with adjusting covariates of demographic characteristics and the rest of coping styles, and positive reinterpretation and growth was the most effective of coping style with OR:0.84. Conclusion: Some personality traits are associated with passive copings and cause high-stress level. So, it could be concluded that improve and strengthen effective coping strategies in individual with maladaptive traits should be considered as a crucial component of prevention and control programs of stress.

  16. Genome wide scan for quantitative trait loci affecting tick resistance in cattle (Bos taurus x Bos indicus)

    National Research Council Canada - National Science Library

    Machado, Marco Antonio; Azevedo, Ana Luisa S; Teodoro, Roberto L; Pires, Maria A; Peixoto, Maria Gabriela C D; de Freitas, Célio; Prata, Márcia Cristina A; Furlong, John; da Silva, Marcos Vinicius G B; Guimarães, Simone E F; Regitano, Luciana C A; Coutinho, Luiz L; Gasparin, Gustavo; Verneque, Rui S

    2010-01-01

    .... Genetic variation between Bos taurus and Bos indicus to tick resistance and molecular biology tools might allow for the identification of molecular markers linked to resistance traits that could be...

  17. Are there stress resistant and susceptible myocardia?

    Science.gov (United States)

    Knight, V A

    1988-11-01

    The satisfactory analysis of the Na/K ATPase, its pumping component and the mechanism of action of the inhibitor digitalis remains elusive; yet the controversial inotropic effect of digitalis in the clinical setting has been known for over a century. There are also conflicting reports of the effect of urea and uremia on the cardiovascular system, and the evidence as it exists, suggests that urea may have two effects on the intact heart, by virtue of its extent of action on hydrogen bonding of water molecules, determined by which type of muscle constitutes the myocardium. If different types of myocardium do exist, they could well respond differently to inotropic agents. Evidence suggests that two types of myocardia, relatively stress resistant or susceptible may exist, analagous to known skeletal muscle differences.

  18. The joint effect of personality traits and perceived stress on pedestrian behavior in a Chinese sample.

    Science.gov (United States)

    Zheng, Tingting; Qu, Weina; Ge, Yan; Sun, Xianghong; Zhang, Kan

    2017-01-01

    While improper pedestrian behavior has become an important factor related to road traffic fatalities, especially in developing countries, the effects of personality traits and/or stress on pedestrian behavior have been rarely reported. The current study explored the joint effects of five personality traits (i.e., extraversion, openness, neuroticism, normlessness and altruism) and global perceived stress (measured with the Perceived Stress Scale-10) on pedestrian behavior (measured with the Pedestrian Behavior Scale) in 311 Chinese individuals. Results showed that altruism, neuroticism and openness significantly affected different pedestrian behavior dimensions, while global perceived stress also significantly and positively predicted positive behavior. Moreover, the effect of neuroticism on positive behavior was fully mediated by stress. Some explanations and implications are provided in the discussion section.

  19. Cognitive trait anxiety, stress and effort interact to predict inhibitory control.

    Science.gov (United States)

    Edwards, Mark S; Edwards, Elizabeth J; Lyvers, Michael

    2017-06-01

    Few studies have focussed on the link between anxiety and inhibitory control in the absence of stimulus-driven external threat. This two-part experiment examined the interactions between (1) somatic trait anxiety, somatic situational stress (i.e. threat of electric shock), and effort, and (2) cognitive trait anxiety, cognitive situational stress (i.e. ego-threat instructions), and effort, on inhibitory processes using a Go-No-Go paradigm. Trait anxiety was operationalised using questionnaire scores and effort was operationalised using a visual analogue scale. Performance effectiveness was measured using the d' parameter from signal detection theory and processing efficiency was indexed by the ratio of d' to response time on correct trials. Results indicated that somatic trait anxiety and stress did not predict effectiveness or efficiency. Cognitive trait anxiety and stress were associated with both inhibitory effectiveness and efficiency deficits; however, contrary to expectations these deficits were evident at higher rather than lower mental effort. Results suggest a distinction between how somatic and cognitive anxiety manifest on tasks involving inhibitory control.

  20. Association of autistic traits in adulthood with childhood abuse, interpersonal victimization, and posttraumatic stress.

    Science.gov (United States)

    Roberts, Andrea L; Koenen, Karestan C; Lyall, Kristen; Robinson, Elise B; Weisskopf, Marc G

    2015-07-01

    Persons with autistic traits may be at elevated risk for interpersonal victimization across the life course. Children with high levels of autistic traits may be targeted for abuse, and deficits in social awareness may increase risk of interpersonal victimization. Additionally, persons with autistic traits may be at elevated risk of posttraumatic stress disorder (PTSD) symptoms subsequent to trauma. We examined retrospectively reported prevalence of childhood abuse, trauma victimization and PTSD symptoms by autistic traits among adult women in a population-based longitudinal cohort, the Nurses' Health Study II (N=1,077). Autistic traits were measured by the 65-item Social Responsiveness Scale. We estimated odds ratios (OR) for childhood sexual and physical/emotional abuse and PTSD symptoms by quintiles of autistic traits. We examined possible mediation of PTSD risk by abuse and trauma type. Women in the highest versus lowest quintile of autistic traits were more likely to have been sexually abused (40.1% versus 26.7%), physically/emotionally abused (23.9% versus 14.3%), mugged (17.1% versus 10.1%), pressured into sexual contact (25.4% versus 15.6%) and have high PTSD symptoms (10.7% versus 4.5%). Odds of PTSD were elevated in women in the top three quintiles of autistic traits compared with the reference group (OR range=1.4 to 1.9). Childhood abuse exposure partly accounted for elevated risk of PTSD in women with autistic traits. We identify for the first time an association between autistic traits, childhood abuse, trauma victimization, and PTSD. Levels of autistic traits that are highly prevalent in the general population are associated with abuse, trauma and PTSD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Normal personality traits, rumination and stress generation among early adolescent girls

    Science.gov (United States)

    Stroud, Catherine B.; Sosoo, Effua E.; Wilson, Sylia

    2017-01-01

    This study examined associations between personality and stress generation. Expanding upon prior work, we examined (a) the role of Positive Emotionality (PE), Negative Emotionality (NE), and Constraint (CON), and their lower-order facets, as predictors of acute and chronic interpersonal stress generation; (b) whether personality moderated effects of rumination on stress generation; and (c) whether personality increased exposure to independent (uncontrollable) stress. These questions were examined in a one-year study of 126 adolescent girls (M age = 12.39 years) using contextual stress interviews. NE predicted increases in acute and chronic interpersonal stress generation, but not independent stress. NE, CON and affiliative PE each moderated the effect of rumination on chronic interpersonal stress generation. These effects were driven by particular lower-order traits. PMID:28845067

  2. Normal personality traits, rumination and stress generation among early adolescent girls.

    Science.gov (United States)

    Stroud, Catherine B; Sosoo, Effua E; Wilson, Sylia

    2015-08-01

    This study examined associations between personality and stress generation. Expanding upon prior work, we examined (a) the role of Positive Emotionality (PE), Negative Emotionality (NE), and Constraint (CON), and their lower-order facets, as predictors of acute and chronic interpersonal stress generation; (b) whether personality moderated effects of rumination on stress generation; and (c) whether personality increased exposure to independent (uncontrollable) stress. These questions were examined in a one-year study of 126 adolescent girls (M age = 12.39 years) using contextual stress interviews. NE predicted increases in acute and chronic interpersonal stress generation, but not independent stress. NE, CON and affiliative PE each moderated the effect of rumination on chronic interpersonal stress generation. These effects were driven by particular lower-order traits.

  3. Proline, catalase and root traits as indices of drought resistance in ...

    African Journals Online (AJOL)

    The present experiment was carried out with 39 bold grained rice genotypes to study the genetic variability of the traits conferring drought resistance and to screen the drought tolerant rice genotypes with a view to formulate an efficient breeding programme for time bound genetic enhancement. The field experiment was ...

  4. Interrelationships between trait anxiety, situational stress and mental effort predict phonological processing efficiency, but not effectiveness.

    Science.gov (United States)

    Edwards, Elizabeth J; Edwards, Mark S; Lyvers, Michael

    2016-08-01

    Attentional control theory (ACT) describes the mechanisms associated with the relationship between anxiety and cognitive performance. We investigated the relationship between cognitive trait anxiety, situational stress and mental effort on phonological performance using a simple (forward-) and complex (backward-) word span task. Ninety undergraduate students participated in the study. Predictor variables were cognitive trait anxiety, indexed using questionnaire scores; situational stress, manipulated using ego threat instructions; and perceived level of mental effort, measured using a visual analogue scale. Criterion variables (a) performance effectiveness (accuracy) and (b) processing efficiency (accuracy divided by response time) were analyzed in separate multiple moderated-regression analyses. The results revealed (a) no relationship between the predictors and performance effectiveness, and (b) a significant 3-way interaction on processing efficiency for both the simple and complex tasks, such that at higher effort, trait anxiety and situational stress did not predict processing efficiency, whereas at lower effort, higher trait anxiety was associated with lower efficiency at high situational stress, but not at low situational stress. Our results were in full support of the assumptions of ACT and implications for future research are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Biochemical basis of the high resistance to oxidative stress in ...

    Indian Academy of Sciences (India)

    Unknown

    the fact that D. discoideum is unusually resistant to oxi- dative stress. To address the biochemical events associated with high resistance to oxidative stress, in D. discoideum, the acti- vity of catalase, SOD and GSH-Px antioxidant enzymes were measured. SOD activity did not show any change in cells subjected to oxidative, ...

  6. Early resistance change and stress/electromigrationmodeling in aluminium interconnects

    NARCIS (Netherlands)

    Petrescu, V.; Mouthaan, A.J.; Schoenmaker, W.

    1997-01-01

    A complete description for early resistance change and two dimensional simulation of mechanical stress evolution in confined Al interconnects, related to the electromigration, is given in this paper. The model, combines the stress/ vacancy concentration evolution with the early resistance change of

  7. Resistance of Some Steels to Stress Corrosion Cracking

    Science.gov (United States)

    Humphries, T. S.; Nelson, E. E.

    1982-01-01

    Evaluations of stress-corrosion cracking resistance of five high-strength low-alloy steels described in report now available. Steels were heat-treated to various tensile strengths and found to be highly resistant to stress-corrosion cracking.

  8. Role of Exercise-Induced Oxidative Stress in Sickle Cell Trait and Disease.

    Science.gov (United States)

    Chirico, Erica N; Faës, Camille; Connes, Philippe; Canet-Soulas, Emmanuelle; Martin, Cyril; Pialoux, Vincent

    2016-05-01

    Sickle cell disease is a class of hemoglobinopathy in humans, which is the most common inherited disease in the world. Although complications of sickle cell disease start from polymerization of red blood cells during its deoxygenating phase, the oxidative stress resulting from the biological processes associated with this disease (ischaemic and hypoxic injuries, hemolysis and inflammation) has been shown to contribute to its pathophysiology. It is widely known that chronic exercise reduces oxidative stress in healthy people, mainly via improvement of antioxidant enzyme efficiency. In addition, recent studies in other diseases, as well as in sickle cell trait carriers and in a mouse model of sickle cell disease, have shown that regular physical activity could decrease oxidative stress. The purpose of this review is to summarize the role of oxidative stress in sickle cell disease and the effects of acute and chronic exercise on the pro-oxidant/antioxidant balance in sickle cell trait and sickle cell disease.

  9. Plasticity in behavioural responses and resistance to temperature stress in Musca domestica

    DEFF Research Database (Denmark)

    Kjaersgaard, Anders; Blackenhorn, Wolf U.; Pertoldi, Cino

    2015-01-01

    performance and morphology of three European populations of Musca domestica (Diptera: Muscidae) originating from different thermal conditions (Spain, Switzerland and Denmark) at benign and stressful high temperatures. Spanish flies showed greater heat resistance than Swiss and Danish flies. Similarly......, at the stressful high temperature Spanish flies flew the furthest and Danish flies the shortest distance. Neither body size nor wing loading affected flight performance, although flies with narrower wings tended to fly further (wing shape effect). Swiss flies were most active in terms of locomotor activity...... at the benign temperature, whereas the Spanish flies were able to stay active for longer at the stressful temperature. Population differences in behavioural traits and heat resistance were obtained using flies held for several generations in a laboratory common garden setting; therefore we suggest that exposure...

  10. Plasma Components as Traits for Resistance to Coccidiosis in Chicken

    DEFF Research Database (Denmark)

    Hamzic, Edin; Bed'Hom, Bertrand; Juin, Hervé

    2014-01-01

    For successful genetic dissection of disease resistance it is of great importance to accurately identify the respective phenotypes. In case of coccidiosis some of the conventional phenotypes don’t fully reflect the animal health status. The objective of this study was large-scale evaluation...... were performed on subset of 184 extreme animals selected based on body weight gain. All fractions of plasma proteins associated with acute phase proteins, except β1-globulin, have been significantly elevated. We observed that the best estimation of plasma coloration variation under a coccidiosis...

  11. Mode of inheritance for biochemical traits in genetically engineered cotton under water stress.

    Science.gov (United States)

    Abid, Muhammad Ali; Malik, Waqas; Yasmeen, Azra; Qayyum, Abdul; Zhang, Rui; Liang, Chengzhen; Guo, Sandui; Ashraf, Javaria

    2016-02-02

    Drought is an abiotic environmental stress that can significantly reduce crop productivity. We examined the mode of inheritance for different biochemical traits including total soluble proteins, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, total phenolic contents and enzymatic antioxidants (superoxide dismutase, peroxidase and catalase), and their relationship with Bacillus thuringiensis (Bt) toxin under control and drought conditions. Eight genetically diverse cotton genotypes were selfed for two generations to ensure homozygosity. Fifteen F1 hybrids were developed by crossing five non-Bt female lines with three Bt male testers. The F1 hybrids and eight parents were finally evaluated under control (100 % field capacity (FC)) and drought (50 % FC) conditions in 2013. The biochemical traits appeared to be controlled by non-additive gene action with low narrow sense heritability estimates. The estimates of general combining ability and specific combining ability for all biochemical traits were significant under control and drought conditions. The genotype-by-trait biplot analysis showed the better performance of Bt cotton hybrids when compared with their parental genotypes for various biochemical traits under control and drought conditions. The biplot and path coefficient analyses revealed the prevalence of different relationships between Cry1Ac toxin and biochemical traits in the control and drought conditions. In conclusion, biochemical traits could serve as potential biochemical markers for breeding Bt cotton genotypes without compromising the optimal level of Bt toxin. Published by Oxford University Press on behalf of the Annals of Botany Company.

  12. The Association between Affective Psychopathic Traits, Time Incarcerated, and Cortisol Response to Psychosocial Stress

    OpenAIRE

    Johnson, Megan M.; Mikolajewski, Amy; Shirtcliff, Elizabeth A.; Eckel, Lisa A.; Taylor, Jeanette

    2015-01-01

    Previous research has demonstrated psychopathic personality traits are significantly predictive of blunted cortisol reactivity to a performance-based stressor task (Trier Social Stress Test; TSST) in college students. However, the relationship between cortisol reactivity and psychopathy has not been explored in high risk samples such as incarcerated populations. Further, the role of imprisonment in relation to cortisol stress reactivity has not been previously explored, but could have practic...

  13. Comorbid Psychopathology and Stress Mediate the Relationship between Autistic Traits and Repetitive Behaviours in Adults with Autism

    Science.gov (United States)

    García-Villamisar, D.; Rojahn, J.

    2015-01-01

    Background: Comorbid psychopathology and stress were considered possible mediators that may explain the relationship between some autistic traits and repetitive behaviours. The current study sought to examine the mediational effects of comorbid psychopathology, executive dysfunctions and stress in the relationship between some autistic traits and…

  14. [Comparison of parameters of stress and trait anxiety scores in teenagers brought up in socially favorable and socially adverse conditions].

    Science.gov (United States)

    A rapetiants, M G; Shkol'nik, T K; Lushchekina, E A

    2007-01-01

    The influence of social deprivation on the level of trait anxiety and stress was studied in the group of 85 teenagers at the age of 15-17 years. Teenagers brought up in socially adverse conditions reveal higher scores of trait anxiety and greater stress, both at the psychological and physiological levels.

  15. Prenatal maternal stress associated with ADHD and autistic traits in early childhood

    Directory of Open Access Journals (Sweden)

    Angelica eRonald

    2011-01-01

    Full Text Available Research suggests that offspring of mothers who experience high levels of stress during pregnancy are more likely to have problems in neurobehavioural development. There is preliminary evidence that prenatal maternal stress (PNMS is a risk factor for both autism and ADHD, however most studies do not control for confounding factors and no study has investigated PNMS as a risk factor for behaviors characteristic of these disorders in early childhood. A population cohort of 2900 pregnant women were recruited before their 18th week of pregnancy and investigated prospectively. Maternal experience of stressful life events was assessed during pregnancy. When offspring were age 2-years, mothers completed the Child Behavior Checklist. Multiple regression showed that maternal stressful events during pregnancy significantly predicted ADHD behaviours in offspring, after controlling for autistic traits and other confounding variables, in both males (p= .03 and females (p= .01. Similarly, stressful events during pregnancy significantly predicted autistic traits in the offspring after controlling for ADHD behaviours and confounding variables, in males only (p= .04. In conclusion, this study suggests that PNMS, in the form of typical stressful live events such as divorce or a residential move, show a small but significant association with both autistic traits and ADHD behaviours independently, in offspring at age 2 years, after controlling for multiple antenatal, obstetric, postnatal and sociodemographic covariates. This finding supports future research using epigenetic, cross-fostering, and gene-environment interaction designs to identify the causal processes underlying this association.

  16. Predisaster Trait Anxiety and Negative Affect Predict Posttraumatic Stress in Youths after Hurricane Katrina

    Science.gov (United States)

    Weems, Carl F.; Pina, Armando A.; Costa, Natalie M.; Watts, Sarah E.; Taylor, Leslie K.; Cannon, Melinda F.

    2007-01-01

    On the basis of theory and previous research, it was hypothesized that predisaster child trait anxiety would predict disaster-related posttraumatic stress symptoms and generalized anxiety disorder symptoms, even after controlling for the number of hurricane exposure events. Results support this hypothesis and further indicate that predisaster…

  17. Impact of psychological stress on the associations between apolipoprotein E variants and metabolic traits: findings in an American sample of caregivers and controls

    DEFF Research Database (Denmark)

    Kring, Sofia Iqbal; Brummett, Beverly H; Barefoot, John

    2010-01-01

    To examine the association between apolipoprotein E (APOE) gene variants and waist circumference, fasting plasma glucose, serum insulin, serum high-density lipoprotein cholesterol, and serum triglycerides, all metabolic traits known as cardiovascular disease (CVD) endophenotypes, in a population...... of stressed individuals and controls. Abdominal obesity, insulin resistance, elevated serum lipid concentration, and APOE polymorphisms have been associated with CVD risk. Current evidence supports the hypothesis that gene-environment interactions modulate serum lipid concentrations....

  18. Multi-stress resistance in Lactococcus lactis is actually escape from purine-induced stress sensitivity

    DEFF Research Database (Denmark)

    Ryssel, Mia; Hviid, Anne-Mette Meisner; Dawish, Mohamed S.

    2014-01-01

    Multi-stress resistance is a widely documented and fascinating phenotype of lactococci where single mutations, preferentially in genes involved in nucleotide metabolism and phosphate uptake, result in elevated tolerance to multiple stresses simultaneously. In this report, we have analysed...

  19. Identification of Quantitative Trait Loci for Resistance to RSIVD in Red Sea Bream (Pagrus major).

    Science.gov (United States)

    Sawayama, Eitaro; Tanizawa, Shiho; Kitamura, Shin-Ichi; Nakayama, Kei; Ohta, Kohei; Ozaki, Akiyuki; Takagi, Motohiro

    2017-12-01

    Red sea bream iridoviral disease (RSIVD) is a major viral disease in red sea bream farming in Japan. Previously, we identified one candidate male individual of red sea bream that was significantly associated with convalescent individuals after RSIVD. The purpose of this study is to identify the quantitative trait loci (QTL) linked to the RSIVD-resistant trait for future marker-assisted selection (MAS). Two test families were developed using the candidate male in 2014 (Fam-2014) and 2015 (Fam-2015). These test families were challenged with RSIV, and phenotypes were evaluated. Then, de novo genome sequences of red sea bream were obtained through next-generation sequencing, and microsatellite markers were searched and selected for linkage map construction. One immune-related gene, MHC class IIβ, was also used for linkage map construction. Of the microsatellite markers searched, 148 and 197 were mapped on 23 and 27 linkage groups in the female and male linkage maps, respectively, covering approximately 65% of genomes in both sexes. One QTL linked to an RSIVD-resistant trait was found in linkage group 2 of the candidate male in Fam-2014, and the phenotypic variance of the QTL was 31.1%. The QTL was closely linked to MHC class IIβ. Moreover, the QTL observed in Fam-2014 was also significantly linked to an RSIVD-resistant trait in the candidate male of Fam-2015. Our results suggest that the RSIVD-resistant trait in the candidate male was controlled by one major QTL closely linked to the MHC class IIβ gene and could be useful for MAS of red sea bream.

  20. Quantitative trait loci identified for blood chemistry components of an advanced intercross line of chickens under heat stress.

    Science.gov (United States)

    Van Goor, Angelica; Ashwell, Christopher M; Persia, Michael E; Rothschild, Max F; Schmidt, Carl J; Lamont, Susan J

    2016-04-14

    Heat stress in poultry results in considerable economic losses and is a concern for both animal health and welfare. Physiological changes occur during periods of heat stress, including changes in blood chemistry components. A highly advanced intercross line, created from a broiler (heat susceptible) by Fayoumi (heat resistant) cross, was exposed to daily heat cycles for seven days starting at 22 days of age. Blood components measured pre-heat treatment and on the seventh day of heat treatment included pH, pCO2, pO2, base excess, HCO3, TCO2, K, Na, ionized Ca, hematocrit, hemoglobin, sO2, and glucose. A genome-wide association study (GWAS) for these traits and their calculated changes was conducted to identify quantitative trait loci (QTL) using a 600 K SNP panel. There were significant increases in pH, base excess, HCO3, TCO2, ionized Ca, hematocrit, hemoglobin, and sO2, and significant decreases in pCO2 and glucose after 7 days of heat treatment. Heritabilities ranged from 0.01-0.21 for pre-heat measurements, 0.01-0.23 for measurements taken during heat, and 0.00-0.10 for the calculated change due to heat treatment. All blood components were highly correlated within measurement days, but not correlated between measurement days. The GWAS revealed 61 QTL for all traits, located on GGA (Gallus gallus chromosome) 1, 3, 6, 9, 10, 12-14, 17, 18, 21-28, and Z. A functional analysis of the genes in these QTL regions identified the Angiopoietin pathway as significant. The QTL that co-localized for three or more traits were on GGA10, 22, 26, 28, and Z and revealed candidate genes for birds' response to heat stress. The results of this study contribute to our knowledge of levels and heritabilities of several blood components of chickens under thermoneutral and heat stress conditions. Most components responded to heat treatment. Mapped QTL may serve as markers for genomic selection to enhance heat tolerance in poultry. The Angiopoietin pathway is likely involved in the

  1. Pre-cold stress increases acid stress resistance and induces amino ...

    African Journals Online (AJOL)

    Pre-cold stress increases acid stress resistance and induces amino acid homeostasis in Lactococcus lactis NZ9000. ... Compared to exposure to acid stress only, pre-adaptation to cold stress decreased the redox balance ratio and the formation of hydroxyl radicals, indicating a change in aerobic respiration and oxidative ...

  2. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways

    Science.gov (United States)

    Bergsma, Alexis L.; Senchuk, Megan M.; Van Raamsdonk, Jeremy M.

    2016-01-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage. PMID:27053445

  3. Personality traits as predictors of depression, anxiety, and stress with secondary school students of final years

    Directory of Open Access Journals (Sweden)

    Vujičić Milena M.

    2017-01-01

    Full Text Available The main aim of this research is to examine the predictive power of personality traits, as defined by the Big five model of personality in expressing depression, anxiety, and stress with secondary school students of final years. The research was conducted on a sample of 977 secondary school students in the third and fourth grade from ten secondary schools in Niš. The gender structure of the sample was as follows: 397 boys and 607 girls. The following instruments were used in the research: Depression Anxiety Stress Scales (DASS-21; Lovibond and Lovibond, 1995, Big Five Inventory - BFI (John, Donahue and Kentle, 1991. The results showed that the regression model constructed by personal traits (Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to experience explain 26% of the criterion variable of Anxiety. The largest individual contribution to the prediction of this variable is achieved by the personal trait Neuroticism (β=.34, p<0.01 . Other personal traits that contribute to the prediction of this variable at a statistically significant level are Extraversion (β =-.17, p<0.01, Agreeableness (β =-.14, p<0.01 and Conscientiousness (β =-.17, p<0.01. The same model explains 37% of the criterion variable Stress. The largest individual contribution to Stress prediction is achieved by the personal trait Neuroticism (β =.57, p<0.01. The same model explains 27% of the criterion variable Anxiety as well. The largest individual contribution to the prediction of this variable is achieved by the personal trait Neuroticism (β =.45, p<0.01, whereas a statistically significant correlation between personal traits Agreeableness (β =-.06, p<0.05 and Conscientious (β =-.12, p<0.01 exists. Results show that the difference between boys and girls in expressing Anxiety (t=-2.96, p<0.01 and Stress (t=-5.01, p<0.01 exists. These emotional states are more expressive with girls. However, there are no differences in expressing Depression

  4. The benefits of being mindful: trait mindfulness predicts less stress reactivity to suppression.

    Science.gov (United States)

    Bullis, Jacqueline R; Bøe, Hans Jakob; Asnaani, Anu; Hofmann, Stefan G

    2014-03-01

    There has been a recent proliferation of research evaluating the efficacy of mindfulness as a clinical intervention. However, there is still little known about trait mindfulness, or how trait mindfulness interacts with maladaptive emotion regulation strategies. The current study further explores the effect of trait mindfulness on emotion regulation, as well as whether specific factors of trait mindfulness are uniquely associated with subjective and autonomic reactivity to stress. Forty-eight healthy male participants were trained in the use of the suppression strategy and then instructed to suppress their responses to the inhalation of a 15% CO2-enriched air mixture for 90 s while their subjective distress and heart rate were recorded. After controlling for anxiety-related variables, the ability to provide descriptions of observed experiences predicted less heart rate reactivity to CO2 inhalation, while skillfulness at restricting attention to the present moment was uniquely predictive of less subjective distress. The tendency to attend to bodily or sensory stimuli predicted greater distress during CO2 inhalation. The inclusion of only healthy males limits the generalizability of study findings. Also, the sample size was relatively small. These findings suggest that factors associated with trait mindfulness predict less stress reactivity and distress while engaging in suppression above and beyond other variables that have been shown to predict anxious responding. The implications for emotion and clinical research are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Aphid symbionts and endogenous resistance traits mediate competition between rival parasitoids.

    Science.gov (United States)

    Kraft, Laura J; Kopco, James; Harmon, Jason P; Oliver, Kerry M

    2017-01-01

    Insects use endogenous mechanisms and infection with protective symbionts to thwart attacks from natural enemies. Defenses that target specific enemies, however, potentially mediate competition between rivals and thereby impact community composition. Following its introduction to North America to control pea aphids (Acyrthosiphon pisum), the parasitoid Aphidius ervi competitively displaced other parasitoids, except for the native Praon pequodorum. The pea aphid exhibits tremendous clonal variation in resistance to A. ervi, primarily through infection with the heritable bacterial symbiont Hamiltonella defensa, although some symbiont-free aphid genotypes encode endogenous resistance. Interestingly, H. defensa strains and aphid genotypes that protect against A. ervi, provide no protection against the closely related, P. pequodorum. Given the specificity of aphid defenses, we hypothesized that aphid resistance traits may contribute to the continued persistence of P. pequodorum. We conducted multiparasitism assays to determine whether aphid resistance traits mediate internal competition between these two solitary parasitoid species, but found this was not the case; P. pequodorum was the successful internal competitor across lines varying in susceptibility to A. ervi. Next, to determine whether resistance traits influence competitive interactions resulting in the stable persistence of P. pequodorum, we established replicated cages varying in the proportion of resistant aphids and recorded successful parasitism for each wasp species over time. As expected, A. ervi outcompeted P. pequodorum in cages containing only susceptible aphids. However, P. pequodorum not only persisted, but was the superior competitor in populations containing any proportion (20-100%) of resistant aphids (20-100%). Smaller scale, better replicated competition cage studies corroborated this finding, and no-competition and behavioral assays provide insight into the processes mediating competition

  6. The effects of perceived stress, traits, mood states, and stressful daily events on salivary cortisol

    NARCIS (Netherlands)

    vanEck, M; Berkhof, H; Nicolson, N; Sulon, J

    1996-01-01

    This study examined the effects of perceived stress and related individual characteristics, mood states, and stressful daily events on salivary cortisol levels. Forty-one ''high stress'' and 46 ''low stress'' subjects were selected on the basis of Perceived Stress Scale scores from a sample of male,

  7. A narrow quantitative trait locus in C. elegans coordinately affects longevity, thermotolerance, and resistance to paraquat

    Directory of Open Access Journals (Sweden)

    Anthony eVertino

    2011-09-01

    Full Text Available By linkage mapping of quantitative trait loci, we previously identified at least 11 natural genetic variants that significantly modulate C. elegans lifespan, many of which would have eluded discovery by knockdown or mutation screens. A region on chromosome IV between markers stP13 and stP35 had striking effects on longevity in three interstrain crosses (each P < 1E–9. In order to define the limits of that interval, we have now constructed two independent lines by marker-based selection during 20 backcross generations, isolating the stP13–stP35 interval from strain Bergerac-BO in a CL2a background. These congenic lines differed significantly from CL2a in lifespan, assayed in two environments (each P<0.001. We then screened for exchange of flanking markers to isolate recombinants that partition this region, because fine mapping the boundaries for overlapping heteroallelic spans can greatly narrow the implicated interval. Recombinants carrying the CL2a allele at stP35 were consistently long-lived compared to those retaining the Bergerac-BO allele (P<0.001, and more resistant to temperature elevation and paraquat (each ~1.7-fold, P<0.0001, but gained little protection from ultraviolet or peroxide stresses. Two rounds of recombinant screening, followed by fine-mapping of break-points and survival testing, narrowed the interval to 0.18 Mb (13.35–13.53 Mb containing 26 putative genes and 6 small-nuclear RNAs – a manageable number of targets for functional assessment.

  8. Mechanisms of yeast resistance to environmental stress 

    Directory of Open Access Journals (Sweden)

    Agata Piecuch

    2013-04-01

    Full Text Available Changes in environmental conditions might be a stress factor for yeast cells. There are several mechanisms of stress tolerance, developed by the cell, which activate when the stress appears. Different transcription factors coordinate the expression of stress response genes. Msn2/4p regulate the expression of the general stress response. Heat shock defense involves heat shock proteins (Hsp, controlled by Hsf1p. Osmotic shock induces the MAP kinase cascade (HOG, whereas the oxidative stress response requires the YAP network. Fungicide resistance is mediated mainly by the activity of membrane transporters and changes in the structure of the plasma membrane. 

  9. Evaluation of phenotypic traits and blight-resistance in an American chestnut backcross orchard in Georgia

    Directory of Open Access Journals (Sweden)

    Martin Cipollini

    2017-04-01

    Full Text Available American chestnut (Castanea dentata was once a cultural, ecological, and economic staple of hardwood forests of the Eastern United States; however, chestnut blight caused by Cryphonectria parasitica has severely threatened its significance. The American Chestnut Foundation (TACF is a non-profit organization that has focused on backcross breeding as a means of restoring C. dentata to the wild. A major goal of this breeding program has been to introduce blight resistance from Chinese chestnut [Castanea mollissima ] while recovering “American chestnut” morphology by backcrossing with C. dentata. The Berry College backcross orchard, in northwest Georgia, was the first such orchard established by TACF with the goal of producing advanced hybrids derived from crosses with wild C. dentata from Georgia (part of TACF’s state chapter program. In 2008, three lines of third backcross (BC3 hybrids were planted at the orchard along with F1, C. mollissima, and C. dentata controls. The theoretical model for the backcross breeding program predicts intermediate blight resistance, at best, in BC3 trees, along with an otherwise American chestnut morphology. This paper focuses on the degree to which this combination of desired traits has been found among the first lines of BC3 trees generated in Georgia. Trees were inoculated with blight in May 2013 (at age 4–5 yrs, and blight resistance was evaluated in October 2013 and March 2014 and used to calculate an average blight-susceptibility index (BSI. In September 2013, branch samples were collected and used to evaluate 20 leaf, stem, and bud traits known to differ consistently between C. mollissima and C. dentata. The average of standardized scores for morphological traits was used as an index of species identity (ISI for each tree. On average, BC3 lines showed significant morphological differences when compared with Chinese chestnut lines, nesting morphologically with American chestnuts. Each BC3 line contained

  10. Marker-Assisted Selection to Pyramid Nematode Resistance and the High Oleic Trait in Peanut

    Directory of Open Access Journals (Sweden)

    Y. Chu

    2011-07-01

    Full Text Available The dynamic challenges of peanut ( L. farming demand a quick response from breeders to develop new cultivars, a process that can be aided by the application of molecular markers. With the goal to pyramid nematode resistance and the trait for high oleic:linoleic acid (high O:L ratio in seeds, nematode-resistant cultivar Tifguard was used as the recurrent female parent and high O:L cultivars Georgia-02C and Florida-07 were used as donor parents for the high O:L trait. ‘Tifguard High O/L’ was generated through three rounds of accelerated backcrossing using BCF progenies selected with molecular markers for these two traits as the pollen donors. Selfed BCF plants yielded marker-homozygous individuals identified as Tifguard High O/L, compressing the hybridization and selection phases of the cultivar development process to less than 3 yr. The accuracy of marker-assisted selection (MAS was confirmed by phenotyping a subset of F populations from both parental combinations. Once additional molecular markers linked with traits of interest are designed to be compatible with high-throughput screening platforms, MAS will be more widely integrated into peanut breeding programs.

  11. Personality traits in rats predict vulnerability and resilience to developing stress-induced depression-like behaviors, HPA axis hyper-reactivity and brain changes in pERK1/2 activity.

    Science.gov (United States)

    Castro, Jorge E; Diessler, Shanaz; Varea, Emilio; Márquez, Cristina; Larsen, Marianne H; Cordero, M Isabel; Sandi, Carmen

    2012-08-01

    Emerging evidence indicates that certain behavioral traits, such as anxiety, are associated with the development of depression-like behaviors after exposure to chronic stress. However, single traits do not explain the wide variability in vulnerability to stress observed in outbred populations. We hypothesized that a combination of behavioral traits might provide a better characterization of an individual's vulnerability to prolonged stress. Here, we sought to determine whether the characterization of relevant behavioral traits in rats could aid in identifying individuals with different vulnerabilities to developing stress-induced depression-like behavioral alterations. We also investigated whether behavioral traits would be related to the development of alterations in the hypothalamic-pituitary-adrenal axis and in brain activity - as measured through phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2)--in response to an acute stressor following either sub-chronic (2 weeks) or chronic (4 weeks) unpredictable stress (CUS). Sprague-Dawley rats were characterized using a battery of behavioral tasks, and three principal traits were identified: anxiety, exploration and activity. When combined, the first two traits were found to explain the variability in the stress responses. Our findings confirm the increased risk of animals with high anxiety developing certain depression-like behaviors (e.g., increased floating time in the forced swim test) when progressively exposed to stress. In contrast, the behavioral profile based on combined low anxiety and low exploration was resistant to alterations related to social behaviors, while the high anxiety and low exploration profile displayed a particularly vulnerable pattern of physiological and neurobiological responses after sub-chronic stress exposure. Our findings indicate important differences in animals' vulnerability and/or resilience to the effects of repeated stress, particularly during initial or

  12. Interactive effects of environmental stress and inbreeding on reproductive traits in a wild bird population.

    Science.gov (United States)

    Marr, A B; Arcese, P; Hochachka, W M; Reid, J M; Keller, L F

    2006-11-01

    1. Conservation biologists are concerned about the interactive effects of environmental stress and inbreeding because such interactions could affect the dynamics and extinction risk of small and isolated populations, but few studies have tested for these interactions in nature. 2. We used data from the long-term population study of song sparrows Melospiza melodia on Mandarte Island to examine the joint effects of inbreeding and environmental stress on four fitness traits that are known to be affected by the inbreeding level of adult birds: hatching success, laying date, male mating success and fledgling survival. 3. We found that inbreeding depression interacted with environmental stress to reduce hatching success in the nests of inbred females during periods of rain. 4. For laying date, we found equivocal support for an interaction between parental inbreeding and environmental stress. In this case, however, inbred females experienced less inbreeding depression in more stressful, cooler years. 5. For two other traits, we found no evidence that the strength of inbreeding depression varied with environmental stress. First, mated males fathered fewer nests per season if inbred or if the ratio of males to females in the population was high, but inbreeding depression did not depend on sex ratio. Second, fledglings survived poorly during rainy periods and if their father was inbred, but the effects of paternal inbreeding and rain did not interact. 6. Thus, even for a single species, interactions between the inbreeding level and environmental stress may not occur in all traits affected by inbreeding depression, and interactions that do occur will not always act synergistically to further decrease fitness.

  13. Infertility Stress: The Role of Coping Strategies, Personality Trait, and Social Support

    Directory of Open Access Journals (Sweden)

    Batool Rashidi

    2011-12-01

    Full Text Available Objective: The aim of our study was to investigate the effect of coping strategies, personality trait and social support as the main social and psychological factors on infertility stress.Materials and methods: This study was conducted on 201 infertile Iranian women referred to the Vali-e-Asr Reproductive health Research Center, and completed the following questionnaires: The fertility problem inventory, measuring perceived infertility related stress (Newton CR, 1999, big five factor personality questionnaire (Farahani, 2009, multidimensional scale of perceived social support MSPS (Zimmet 1988, and multidimensional assessment of coping (Endler, 1990.The results were then analyzed using the Pearson Correlation and stepwise regression.Results: Infertility stress has negative and significant relation with emotion-oriented coping method, perceived social support and bring extrovert. It has a positive, significant relation with emotion-oriented coping method, obsessive compulsive disorder (OCD. The results of the stepwise regression showed that emotion-oriented coping method, OCD and being extrovert are suitable predictors of infertility stress.Conclusion: About 22% of the infertility stress variance was explained by coping strategies and personality trait. Therefore our result demonstrates the importance of social and psychological factors on experiencing the infertility stress.

  14. Mapping a Quantitative Trait Locus (QTL conferring pyrethroid resistance in the African malaria vector Anopheles funestus

    Directory of Open Access Journals (Sweden)

    Hunt Richard H

    2007-01-01

    Full Text Available Abstract Background Pyrethroid resistance in Anopheles funestus populations has led to an increase in malaria transmission in southern Africa. Resistance has been attributed to elevated activities of cytochrome P450s but the molecular basis underlying this metabolic resistance is unknown. Microsatellite and SNP markers were used to construct a linkage map and to detect a quantitative trait locus (QTL associated with pyrethroid resistance in the FUMOZ-R strain of An. funestus from Mozambique. Results By genotyping 349 F2 individuals from 11 independent families, a single major QTL, rp1, at the telomeric end of chromosome 2R was identified. The rp1 QTL appears to present a major effect since it accounts for more than 60% of the variance in susceptibility to permethrin. This QTL has a strong additive genetic effect with respect to susceptibility. Candidate genes associated with pyrethroid resistance in other species were physically mapped to An. funestus polytene chromosomes. This showed that rp1 is genetically linked to a cluster of CYP6 cytochrome P450 genes located on division 9 of chromosome 2R and confirmed earlier reports that pyrethroid resistance in this strain is not associated with target site mutations (knockdown resistance. Conclusion We hypothesize that one or more of these CYP6 P450s clustered on chromosome 2R confers pyrethroid resistance in the FUMOZ-R strain of An. funestus.

  15. Genome-wide association analysis of seedling traits in diverse Sorghum germplasm under thermal stress.

    Science.gov (United States)

    Chopra, Ratan; Burow, Gloria; Burke, John J; Gladman, Nicholas; Xin, Zhanguo

    2017-01-13

    Climate variability due to fluctuation in temperature is a worldwide concern that imperils crop production. The need to understand how the germplasm variation in major crops can be utilized to aid in discovering and developing breeding lines that can withstand and adapt to temperature fluctuations is more necessary than ever. Here, we analyzed the genetic variation associated with responses to thermal stresses in a sorghum association panel (SAP) representing major races and working groups to identify single nucleotide polymorphisms (SNPs) that are associated with resilience to temperature stress in a major cereal crop. The SAP exhibited extensive variation for seedling traits under cold and heat stress. Genome-wide analyses identified 30 SNPs that were strongly associated with traits measured at seedling stage under cold stress and tagged genes that act as regulators of anthocyanin expression and soluble carbohydrate metabolism. Meanwhile, 12 SNPs were significantly associated with seedling traits under heat stress and these SNPs tagged genes that function in sugar metabolism, and ion transport pathways. Evaluation of co-expression networks for genes near the significantly associated SNPs indicated complex gene interactions for cold and heat stresses in sorghum. We focused and validated the expression of four genes in the network of Sb06g025040, a basic-helix-loop-helix (bHLH) transcription factor that was proposed to be involved in purple color pigmentation of leaf, and observed that genes in this network were upregulated during cold stress in a moderately tolerant line as compared to the more sensitive line. This study facilitated the tagging of genome regions associated with variation in seedling traits of sorghum under cold and heat stress. These findings show the potential of genotype information for development of temperature resilient sorghum cultivars and further characterization of genes and their networks responsible for adaptation to thermal stresses

  16. Signal Traits and Oxidative Stress: A Comparative Study Across Populations with Divergent Signals

    Directory of Open Access Journals (Sweden)

    Maren N Vitousek

    2016-05-01

    Full Text Available Diverging populations often shift patterns of signal use – a process that can contribute to reproductive isolation and speciation. Yet it is not clear why most traits gain or lose signal value during divergence. One reason this could occur is because changes in the relationship between signals and relevant physiological parameters degrade the reliability of a signal, or even change its underlying information content. Here we test the hypothesis that the relationship between signal trait elaboration and a central component of organismal health – oxidative stress – differs across closely related populations that have diverged in signal use and preferences. In the recently diverged barn swallow subspecies complex (Hirundo rustica, Family: Hirundinidae, different populations use different traits as sexual signals. Two of these traits, ventral breast plumage color and tail streamer length, differ markedly between North American H. r. erythrogaster and European H. r. rustica. Despite this divergence, variation in ventral plumage color was similarly associated with measures of oxidative damage across both populations. However, the directionality of these relationships differed between the sexes: darker male barn swallows had higher levels of plasma oxidative damage than their lighter counterparts, while the opposite relationship was seen in females. In contrast, relationships between tail streamer length and measures of oxidative stress were not consistent across populations. Some analyses indicated that in European H. r. rustica, where males bearing elongated streamers are preferred as mates, longer-streamered males were more oxidatively stressed; however, the opposite pattern was suggested in North American H. r. erythrogaster. Tail streamer length was not associated with measures of oxidative stress in females of either population. Differences in the physiological state of stronger signalers across populations and between the sexes may be

  17. Population structure and association analysis of heat stress relevant traits in chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Jha, Uday Chand; Jha, Rintu; Bohra, Abhishek; Parida, Swarup Kumar; Kole, Paresh Chandra; Thakro, Virevol; Singh, Deepak; Singh, Narendra Pratap

    2018-01-01

    Understanding genetic diversity and population structure is prerequisite to broaden the cultivated base of any crop. In the current investigation, we report discovery of a total of 319 alleles by assaying 81 SSRs on 71 chickpea genotypes. The cluster analysis based on Jaccard coefficient and unweighted neighbor joining algorithm categorized all genotypes into two major clusters. Cultivars grown within the same agro-climatic zones were clustered together, whereas the remaining genotypes particularly advanced breeding lines and accessions assigned to another cluster. Population structure analysis separated the entire collection into two subpopulations (K = 2) and the clustering pattern remained in close agreement with those of distance-based methods. Importantly, we also discovered marker trait association for membrane stability index (MSI) and leaf chlorophyll content measured as SPAD chlorophyll meter reading (SCMR), the two important physiological parameters indicative of heat stress (HS) tolerance in chickpea. Association analysis using both general linear and mixed linear models of the mean phenotypic data of traits recorded in 2016 and 2017 uncovered significant association of NCPGR206 and H2L102 with the MSI trait. Likewise, SSR markers GA9, TR31 and TA113 exhibited significant association with SCMR trait. The genomic regions putatively linked with two traits may be investigated in greater detail to further improve knowledge about the genetic architecture of HS tolerance in chickpea.

  18. Individual differences in delay discounting under acute stress: the role of trait perceived stress

    Directory of Open Access Journals (Sweden)

    Karolina M. Lempert

    2012-07-01

    Full Text Available Delay discounting refers to the reduction of the value of a future reward as the delay to that reward increases. The rate at which individuals discount future rewards varies as a function of both individual and contextual differences, and high delay discounting rates have been linked with problematic behaviors, including drug abuse and gambling. The current study investigated the effects of acute anticipatory stress on delay discounting, while considering two important factors: individual perceptions of stress and whether the stressful situation is future-focused or present-focused. Half of the participants experienced acute stress by anticipating giving a videotaped speech. This stress was either future-oriented (speech about future job or present-oriented (speech about physical appearance. They then performed a delay discounting task, in which they chose between smaller, immediate rewards and larger, delayed rewards. Their scores on the Perceived Stress Scale were also collected. The way in which one appraises a stressful situation interacts with acute stress to influence choices; under stressful conditions, delay discounting rate was highest in individuals with low perceived stress and lowest for individuals with high perceived stress. This result might be related to individual variation in reward responsiveness under stress. Furthermore, the time orientation of the task interacted with its stressfulness to affect the individual’s propensity to choose immediate rewards. These findings add to our understanding of the intermediary factors between stress and decision making.

  19. The Relationship Between Personality Traits, Stress and Job Satisfaction of Employees of Iran Telecom Companies

    Directory of Open Access Journals (Sweden)

    Zahra Zamanian

    2015-11-01

    Full Text Available Background & Objectives: Job satisfaction is affected by several factors including personality characteristics and job stress. This study aimed to investigate the relationship between personality traits, job satisfaction, and stress-related. Materials and Methods: This analytical study was performed among the telecommunications industry workers. 254 persons were randomly selected as the population of the study . Eysenck Personality Questionnaire and job satisfaction and stress questionnaires were applied to gather the required data. The collected data were analyzed using SPSS statistical software. Results: There was an inverse relationship between job satisfaction and job stress. The results of job stress questionnaires showed that 176, 37, and 8 employees were under high, moderate, and low stress, respectively. Overall job satisfaction scores were 14.25 + 10.95. The relationship between job stress and scale E showed a significant positive correlation between two variables so that as the level of introspection increases, people will feel more jop stress. The two scale N and L have meaningful relationship with job satisfaction so that the more stable the character, the higher the job satisfaction . Conclusion: It can be concluded that in order for promoting the job satisfaction and reducing the job stress, self-confidence enhancing skills should be trained to the employees.

  20. Pre-cold stress increases acid stress resistance and induces amino ...

    African Journals Online (AJOL)

    Methods: Bacterial strains were grown at 4 °C for 2 h pre-adaptation, and then subjected to various stresses including exposure to ... Keywords: Pre-cold stress, Acis stress resistance, Lactococcus lactis, Redox balance, Amino acid homeostasis. Tropical ... differs in metabolism and production [4] and viability and metabolic ...

  1. Evaluating Freezing Resistance in Barley (Hordeum vulgare L. Using Molecular Markers and Some Physiological Traits

    Directory of Open Access Journals (Sweden)

    Omid Sofalian

    2013-08-01

    Full Text Available To evaluate the freezing resistance and genetic diversity in barley physiological traits, molecular markers and their relationship in 20 barley genotypes were assessed in field and greenhouse condition. The analysis of variance showed a significant difference among studied genotypes. The effect of acclimation temperature on prolin content, quantum efficiency of photosystem II, chlorophyll and soluble sugars content were studied as physiological traits. Freezing treatments were -4, -7, -10, -13 and -16°C temperatures that applied in a 3 replicated randomized complete block design. Then their lethal temperature at which 50% of plant were died (LT50 was determined. To estimate FSI (Field Survival Index index, the 20 genotypes were cultured in a separate experiment on field with 3 replications. The results showed negative significant correlation (-0.601 between field survival index and LT50. Cluster analysis using physiological traits, genotypes of F-A1-1, F-A1-2, F-A2-11, F-GRB-85-5, Sahra, Sahand, Dasht and Makouei were categorized in a distinct group and had a high FSI and low LT50. Makouei cultivar having LT50=-17.66°C and the highest percentage of winter survival in the field, was the most resistant genotype. 10 ISSR markers from 35 primers sequences were selected and used. These 9 ISSR primers produced 50 polymorphic bands. PIC and MI average index for all primers were 0.37 and 1.72 respectively. Cluster analysis of molecular data using Jaccard similarity coefficient categorized the genotypes to four distinct groups. Associations between molecular markers and traits were assessed by multiple regression analysis. Some informative markers related to FSI and also LT50 was determined. So it may be possible to use these markers for selection of resistant lines or genotypes in breeding programs.

  2. Cross-stress resistance in Saccharomyces cerevisiae yeast?new insight into an old phenomenon

    OpenAIRE

    ?wi?ci?o, Agata

    2016-01-01

    Acquired stress resistance is the result of mild stress causing the acquisition of resistance to severe stress of the same or a different type. The mechanism of ?same-stress? resistance (resistance to a second, strong stress after mild primary stress of the same type) probably depends on the activation of defense and repair mechanisms specific for a particular type of stress, while cross-stress resistance (i.e., resistance to a second, strong stress after a different type of mild primary stre...

  3. Peritraumatic and trait dissociation differentiate police officers with resilient versus symptomatic trajectories of posttraumatic stress symptoms.

    Science.gov (United States)

    Galatzer-Levy, Isaac R; Madan, Anita; Neylan, Thomas C; Henn-Haase, Clare; Marmar, Charles R

    2011-10-01

    Research has consistently demonstrated that stress reactions to potentially traumatic events do not represent a unified phenomenon. Instead, individuals tend to cluster into prototypical response patterns over time including chronic symptoms, recovery, and resilience. We examined heterogeneity in a posttraumatic stress disorder (PTSD) symptom course in a sample of 178 active-duty police officers following exposure to a life-threatening event using latent growth mixture modeling (LGMM). This analysis revealed 3 discrete PTSD symptom trajectories: resilient (88%), distressed-improving (10%), and distressed-worsening (2%). We further examined whether trait and peritraumatic dissociation distinguished these symptom trajectories. Findings indicate that trait and peritraumatic dissociation differentiated the resilient from the distressed-improving trajectory (trait, p resilient from the distressed-worsening trajectory (p resilient group overall. Furthermore, though there is abundant evidence that dissociation has a positive linear relationship with PTSD symptoms, this study demonstrates that degree of dissociation can distinguish between resilient and symptomatic groups of individuals. Copyright © 2011 International Society for Traumatic Stress Studies.

  4. Wheat multiple synthetic derivatives: a new source for heat stress tolerance adaptive traits.

    Science.gov (United States)

    Elbashir, Awad Ahmed Elawad; Gorafi, Yasir Serag Alnor; Tahir, Izzat Sidahmed Ali; Kim, June-Sik; Tsujimoto, Hisashi

    2017-06-01

    Heat stress is detrimental to wheat (Triticum aestivum L.) productivity. In this study, we aimed to select heat-tolerant plants from a multiple synthetic derivatives (MSD) population and evaluate their agronomic and physiological traits. We selected six tolerant plants from the population with the background of the cultivar 'Norin 61' (N61) and established six MNH (MSD population of N61 selected as heat stress-tolerant) lines. We grew these lines with N61 in the field and growth chamber. In the field, we used optimum and late sowings to ensure plant exposure to heat. In the growth chamber, in addition to N61, we used the heat-tolerant cultivars 'Gelenson' and 'Bacanora'. We confirmed that MNH2 and MNH5 lines acquired heat tolerance. These lines had higher photosynthesis and stomata conductance and exhibited no reduction in grain yield and biomass under heat stress compared to N61. We noticed that N61 had relatively good adaptability to heat stress. Our results indicate that the MSD population includes the diversity of Aegilops tauschii and is a promising resource to uncover useful quantitative traits derived from this wild species. Selected lines could be useful for heat stress tolerance breeding.

  5. The "STAY-GREEN" trait and phytohormone signaling networks in plants under heat stress.

    Science.gov (United States)

    Abdelrahman, Mostafa; El-Sayed, Magdi; Jogaiah, Sudisha; Burritt, David J; Tran, Lam-Son Phan

    2017-07-01

    The increasing demand for food and the heavy yield losses in primary crops due to global warming mean that there is an urgent need to improve food security. Therefore, understanding how plants respond to heat stress and its consequences, such as drought and increased soil salinity, has received much attention in plant science community. Plants exhibit stress tolerance, escape or avoidance via adaptation and acclimatization mechanisms. These mechanisms rely on a high degree of plasticity in their cellular metabolism, in which phytohormones play an important role. "STAY-GREEN" is a crucial trait for genetic improvement of several crops, which allows plants to keep their leaves on the active photosynthetic level under stress conditions. Understanding the physiological and molecular mechanisms concomitant with "STAY-GREEN" trait or delayed leaf senescence, as well as those regulating photosynthetic capability of plants under heat stress, with a certain focus on the hormonal pathways, may be a key to break the plateau of productivity associated with adaptation to high temperature. This review will discuss the recent findings that advance our understanding of the mechanisms controlling leaf senescence and hormone signaling cascades under heat stress.

  6. GM trees with increased resistance to herbivores: trait efficiency and their potential to promote tree growth

    Directory of Open Access Journals (Sweden)

    Joakim eHjältén

    2015-05-01

    Full Text Available Climate change, as well as a more intensive forestry, is expected to increase the risk of damage by pests and pathogens on trees, which can already be a severe problem in tree plantations. Recent development of biotechnology theoretically allows for resistance enhancement that could help reduce these risks but we still lack a comprehensive understanding of benefits and tradeoffs with pest resistant GM (genetically modified trees. We synthesized the current knowledge on the effectiveness of GM forest trees with increased resistance to herbivores. There is ample evidence that induction of exogenous Bacillus thuringiensis genes reduce performance of target pests whereas upregulation of endogenous resistance traits e.g. phenolics, generates variable results. Our review identified very few studies estimating the realized benefits in tree growth of GM trees in the field. This is concerning as the realized benefit with insect resistant GM plants seems to be context-dependent and likely manifested only if herbivore pressure is sufficiently high. Future studies of secondary pest species and resistance evolution in pest to GM trees should be prioritized. But most importantly we need more long-term field tests to evaluate the benefits and risks with pest resistant GM trees.

  7. GM trees with increased resistance to herbivores: trait efficiency and their potential to promote tree growth.

    Science.gov (United States)

    Hjältén, Joakim; Axelsson, E Petter

    2015-01-01

    Climate change, as well as a more intensive forestry, is expected to increase the risk of damage by pests and pathogens on trees, which can already be a severe problem in tree plantations. Recent development of biotechnology theoretically allows for resistance enhancement that could help reduce these risks but we still lack a comprehensive understanding of benefits and tradeoffs with pest resistant GM (genetically modified) trees. We synthesized the current knowledge on the effectiveness of GM forest trees with increased resistance to herbivores. There is ample evidence that induction of exogenous Bacillus thuringiensis genes reduce performance of target pests whereas upregulation of endogenous resistance traits e.g., phenolics, generates variable results. Our review identified very few studies estimating the realized benefits in tree growth of GM trees in the field. This is concerning as the realized benefit with insect resistant GM plants seems to be context-dependent and likely manifested only if herbivore pressure is sufficiently high. Future studies of secondary pest species and resistance evolution in pest to GM trees should be prioritized. But most importantly we need more long-term field tests to evaluate the benefits and risks with pest resistant GM trees.

  8. Genetic dissection of milk yield traits and mastitis resistance quantitative trait loci on chromosome 20 in dairy cattle.

    Science.gov (United States)

    Kadri, Naveen K; Guldbrandtsen, Bernt; Lund, Mogens S; Sahana, Goutam

    2015-12-01

    Intense selection to increase milk yield has had negative consequences for mastitis incidence in dairy cattle. Due to low heritability of mastitis resistance and an unfavorable genetic correlation with milk yield, a reduction in mastitis through traditional breeding has been difficult to achieve. Here, we examined quantitative trait loci (QTL) that segregate for clinical mastitis and milk yield on Bos taurus autosome 20 (BTA20) to determine whether both traits are affected by a single polymorphism (pleiotropy) or by multiple closely linked polymorphisms. In the latter but not the former situation, undesirable genetic correlation could potentially be broken by selecting animals that have favorable variants for both traits. First, we performed a within-breed association study using a haplotype-based method in Danish Holstein cattle (HOL). Next, we analyzed Nordic Red dairy cattle (RDC) and Danish Jersey cattle (JER) with the goal of determining whether these QTL identified in Holsteins were segregating across breeds. Genotypes for 12,566 animals (5,966 HOL, 5,458 RDC, and 1,142 JER) were determined by using the Illumina Bovine SNP50 BeadChip (50K; Illumina, San Diego, CA), which identifies 1,568 single nucleotide polymorphisms on BTA20. Data were combined, phased, and clustered into haplotype states, followed by within- and across-breed haplotype-based association analyses using a linear mixed model. Association signals for both clinical mastitis and milk yield peaked in the 26- to 40-Mb region on BTA20 in HOL. Single-variant association analyses were carried out in the QTL region using whole sequence level variants imputed from references of 2,036 HD genotypes (BovineHD BeadChip; Illumina) and 242 whole-genome sequences. The milk QTL were also segregating in RDC and JER on the BTA20-targeted region; however, an indication of differences in the causal factor(s) was observed across breeds. A previously reported F279Y mutation (rs385640152) within the growth hormone

  9. Phenotypic covariance of longevity, immunity and stress resistance in the caenorhabditis nematodes.

    Directory of Open Access Journals (Sweden)

    Francis R G Amrit

    2010-04-01

    Full Text Available Ageing, immunity and stresstolerance are inherent characteristics of all organisms. In animals, these traits are regulated, at least in part, by forkhead transcription factors in response to upstream signals from the Insulin/Insulin-like growth factor signalling (IIS pathway. In the nematode Caenorhabditis elegans, these phenotypes are molecularly linked such that activation of the forkhead transcription factor DAF-16 both extends lifespan and simultaneously increases immunity and stress resistance. It is known that lifespan varies significantly among the Caenorhabditis species but, although DAF-16 signalling is highly conserved, it is unclear whether this phenotypic linkage occurs in other species. Here we investigate this phenotypic covariance by comparing longevity, stress resistance and immunity in four Caenorhabditis species.We show using phenotypic analysis of DAF-16 influenced phenotypes that among four closely related Caenorhabditis nematodes, the gonochoristic species (Caenorhabditis remanei and Caenorhabditis brenneri have diverged significantly with a longer lifespan, improved stress resistance and higher immunity than the hermaphroditic species (C. elegans and Caenorhabditis briggsae. Interestingly, we also observe significant differences in expression levels between the daf-16 homologues in these species using Real-Time PCR, which positively correlate with the observed phenotypes. Finally, we provide additional evidence in support of a role for DAF-16 in regulating phenotypic coupling by using a combination of wildtype isolates, constitutively active daf-16 mutants and bioinformatic analysis.The gonochoristic species display a significantly longer lifespan (p<0.0001 and more robust immune and stress response (p<0.0001, thermal stress; p<0.01, heavy metal stress; p<0.0001, pathogenic stress than the hermaphroditic species. Our data suggests that divergence in DAF-16 mediated phenotypes may underlie many of the differences observed

  10. [Personal traits and a sense of job-related stress in a military aviation crew].

    Science.gov (United States)

    Cabarkapa, Milanko; Korica, Vesna; Rodjenkov, Sanja

    2011-02-01

    Accelerated technological and organizational changes in numerous professions lead to increase in job-related stress. Since these changes are particularly common in military aviation, this study examined the way military aviation crew experiences job-related stress during a regular aviation drill, depending on particular social-demographic factors and personal traits. The modified Cooper questionnaire was used to examine the stress related factors at work. The questionnaire was adapted for the aviation crew in the army environment. Personal characteristics were examined using the NEO-PI-R personality inventory. The study included 50 examinees (37 pilots and 13 other crew members) employed in the Serbian Army. The studies were performed during routine physical examinations at the Institute for Aviation Medicine during the year 2007. Statistical analysis of the study results contained descriptive analysis, one-way analysis of variance and correlation analysis. It was shown that army aviation crew works under high stress. The highest stress value had the intrinsic factor (AS = 40.94) and role in organisation (AS = 39.92), while the lowest one had the interpersonal relationship factor (AS = 29.98). The results also showed that some social-demographic variables (such as younger examinees, shorter working experience) and neuroticism as a personality trait, were in correlation with job-related stress. Stress evaluation and certain personality characteristics examination can be used for the development of the basic anti-stress programs and measures in order to achieve better psychological selection, adaptation career leadership and organization of military pilots and other crew members.

  11. Personal traits and a sense of job-related stress in a military aviation crew

    Directory of Open Access Journals (Sweden)

    Čabarkapa Milanko

    2011-01-01

    Full Text Available Background/Aim. Accelerated technological and organizational changes in numerous professions lead to increase in jobrelated stress. Since these changes are particularly common in military aviation, this study examined the way military aviation crew experiences job-related stress during a regular aviation drill, depending on particular social-demographic factors and personal traits. Methods. The modified Cooper questionnaire was used to examine the stress related factors at work. The questionnaire was adapted for the aviation crew in the army environment. Personal characteristics were examined using the NEO-PI-R personality inventory. The study included 50 examinees (37 pilots and 13 other crew members employed in the Serbian Army. The studies were performed during routine physical examinations at the Institute for Aviation Medicine during the year 2007. Statistical analysis of the study results contained descriptive analysis, one-way analysis of variance and correlation analysis. Results. It was shown that army aviation crew works under high stress. The highest stress value had the intrinsic factor (AS = 40.94 and role in organisation (AS = 39.92, while the lowest one had the interpersonal relationship factor (AS = 29.98. The results also showed that some social-demographic variables (such as younger examinees, shorter working experience and neuroticism as a personality trait, were in correlation with job-related stress. Conclusion. Stress evaluation and certain personality characteristics examination can be used for the devalopment of the basic anti-stress programs and measures in order to achieve better psychological selection, adaptation career leadership and organization of military pilots and other crew members.

  12. [Frost-resistance of subtropical evergreen woody plants: an evaluation based on plant functional traits].

    Science.gov (United States)

    Xu, Yi-Lu; Yang, Xiao-Dong; Xu, Yue; Xie, Yi-Ming; Wang, Liang-Yan; Yan, En-Rong

    2012-12-01

    Evaluating the frost-resistance of evergreen woody plants is of significance in guiding the species selection in forest management in subtropical region. In this paper, an investigation was made on the functional traits (including specific leaf area, stem wood density, leaf area, leaf dry matter content, leaf relative electrical conductance, and twig wood density) of 64 common evergreen broad-leaved and coniferous woody plant species in the Ningbo region of Zhejiang Province, East China, after a severe snowstorm in early 2008, aimed to select the evergreen woody plants with high ability of freeze-tolerance, and to establish a related evaluation system. By using a hierarchy analysis approach, the weight values of the functional traits of each species were determined, and an index system for evaluating the plants tolerance ability against freeze and mechanical damage was established. Based on this system, 23 evergreen plant species with high tolerance ability against freeze and mechanical damage, such as Cyclobalanopsis gilva, Cyclobalanopsis nubium, Neolitsea aurata, and Vacciniuim mandarinorum, were selected. In the meantime, on the basis of the ordering with each of the functional traits, the ordering of the tolerance ability of the 64 plant species against freeze and mechanical damage was made, and a list for the frost-resistance ability of the subtropical evergreen woody plant species in Ningbo region was constituted.

  13. Association mapping of seed and disease resistance traits in Theobroma cacao L.

    Science.gov (United States)

    Motilal, Lambert A; Zhang, Dapeng; Mischke, Sue; Meinhardt, Lyndel W; Boccara, Michel; Fouet, Olivier; Lanaud, Claire; Umaharan, Pathmanathan

    2016-12-01

    Microsatellite and single nucleotide polymorphism markers that could be used in marker assisted breeding of cacao were identified for number of filled seeds, black pod resistance and witches' broom disease resistance. An association mapping approach was employed to identify markers for seed number and resistance to black pod and witches' broom disease (WBD) in cacao (Theobroma cacao L.). Ninety-five microsatellites (SSRs) and 775 single nucleotide polymorphisms (SNPs) were assessed on 483 unique trees in the International Cocoa Genebank Trinidad (ICGT). Linkage disequilibrium (LD) and association mapping studies were conducted to identify markers to tag the phenotypic traits. Decay of LD occurred over an average 9.3 cM for chromosomes 1-9 and 2.5 cM for chromosome 10. Marker/trait associations were generally identified based on general linear models (GLMs) that incorporated principal components from molecular information on relatedness factor. Seven markers (mTcCIR 8, 66, 126, 212; TcSNP368, 697, 1370) on chromosomes 1 and 9 were identified for number of filled seeds (NSEED). A single marker was found for black pod resistance (mTcCIR280) on chromosome 3, whereas six markers on chromosomes 4, 5, 6, 8, and 10 were detected for WBD (mTcCIR91, 183; TcSNP375, 720, 1230 and 1374). It is expected that this association mapping study in cacao would contribute to the knowledge of the genetic determinism of cocoa traits and that the markers identified herein would prove useful in marker assisted breeding of cacao.

  14. Inner-City High School Teachers: The Relationship of Personality Traits and Teaching Style to Environmental Stress.

    Science.gov (United States)

    Parkay, Forrest W.

    1980-01-01

    Studies how teachers respond to environmental stress and whether certain personality traits are related to these response patterns. Concludes that generalized personality traits are indicative of teaching styles that emerge in response to anxiety-provoking environmental conditions. Tables included. (Author/JLF)

  15. New biotechnological tools to accelerate scab-resistance trait transfer to apple

    Directory of Open Access Journals (Sweden)

    Roberta Cusin

    Full Text Available Abstract Apple is a fruit crop cultivated worldwide. Apple orchards are exposed to a diverse set of environmental and biological factors that affect the productivity and sustainability of the culture. Many of the efforts and costs for apple production rely on reducing the incidence of fungal diseases, and one of the main diseases is apple scab caused by the fungus Venturia inaequalis. The economic impact of scab on apple productivity has guided many breeding programs to search for cultivars resistant to apple scab. Introgression from wild relatives has been successful to some extent, and genetic engineering for resistant cultivars has even been employed. This review presents the techniques used to the present time to obtain pathogen-resistant apple cultivars and introduces new biotechnological approaches based on plant plasmids that show promising results for delivering genetic traits with a short-term perspective.

  16. EFFECTS OF ZEOLITE AND SELENIUM APPLICATIONS ON SOME AGRONOMIC TRAITS OF THREE CANOLA CULTIVARS UNDER DROUGHT STRESS

    National Research Council Canada - National Science Library

    Hossein Zahedi; Amir Hossein Shirani Rad; Hamid Reza Tohidi Moghadam

    2011-01-01

      In order to study the effects of zeolite and selenium application on the agronomic traits of three canola cultivars under drought stress conditions, an experiment was conducted in two growing seasons (2006 and 2007...

  17. Limited fitness costs of herbicide-resistance traits in Amaranthus tuberculatus facilitate resistance evolution.

    Science.gov (United States)

    Wu, Chenxi; Davis, Adam S; Tranel, Patrick J

    2018-02-01

    The fitness cost of herbicide resistance (HR) in the absence of herbicide selection plays a key role in HR evolution. Quantifying the fitness cost of resistance, however, is challenging, and there exists a knowledge gap in this area. A synthetic (artificially generated) Amaranthus tuberculatus population segregating for five types of HR was subjected to competitive growth conditions in the absence of herbicide selection for six generations. Fitness costs were quantified by using a combination of phenotyping and genotyping to monitor HR frequency changes over generations. In the absence of herbicide selection, a significant fitness cost was observed for resistance to acetolactate synthase-inhibiting herbicides, but not for resistances to atrazine (non-target-site resistance mechanism), protoporphyrinogen oxidase inhibitors, 4-hydroxyphenylpryuvate dioxygenase inhibitors or glyphosate. Glyphosate resistance was conferred by multiple mechanisms in the synthetic population, and further analysis revealed that one mechanism, amplification of the 5-enolypyruvylshikimate-3-phosphate synthase gene, did decrease in frequency. Our results indicate that herbicide-resistance mitigation strategies (e.g. herbicide rotation) that rely on the existence of fitness costs in the absence of herbicide selection likely will be largely ineffective in many cases. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Adaptive value of phenological traits in stressful environments: predictions based on seed production and laboratory natural selection.

    Directory of Open Access Journals (Sweden)

    Benjamin Brachi

    Full Text Available Phenological traits often show variation within and among natural populations of annual plants. Nevertheless, the adaptive value of post-anthesis traits is seldom tested. In this study, we estimated the adaptive values of pre- and post-anthesis traits in two stressful environments (water stress and interspecific competition, using the selfing annual species Arabidopsis thaliana. By estimating seed production and by performing laboratory natural selection (LNS, we assessed the strength and nature (directional, disruptive and stabilizing of selection acting on phenological traits in A. thaliana under the two tested stress conditions, each with four intensities. Both the type of stress and its intensity affected the strength and nature of selection, as did genetic constraints among phenological traits. Under water stress, both experimental approaches demonstrated directional selection for a shorter life cycle, although bolting time imposes a genetic constraint on the length of the interval between bolting and anthesis. Under interspecific competition, results from the two experimental approaches showed discrepancies. Estimation of seed production predicted directional selection toward early pre-anthesis traits and long post-anthesis periods. In contrast, the LNS approach suggested neutrality for all phenological traits. This study opens questions on adaptation in complex natural environment where many selective pressures act simultaneously.

  19. The interactive effect of change in perceived stress and trait anxiety on vagal recovery from cognitive challenge

    Science.gov (United States)

    Crowley, Olga V.; McKinley, Paula S.; Burg, Matthew M.; Schwartz, Joseph E.; Ryff, Carol D.; Weinstein, Maxine; Seeman, Teresa E.; Sloan, Richard P.

    2012-01-01

    The present study tested the hypothesis that the change in state negative affect (measured as perceived stress) after cognitive challenge moderates the relationship of trait anxiety and anger to vagal recovery from that challenge. Cardiac vagal control (assessed using heart rate variability) and respiratory rate were measured in a sample of 905 participants from the Midlife in the United States Study. Cognitive challenges consisted of computerized mental arithmetic and Stroop color-word matching tasks. Multiple regression analyses controlling for the effects of the demographic, lifestyle, and medical factors influencing cardiac vagal control showed a significant moderating effect of change in perceived stress on the relationship of trait anxiety to vagal recovery from cognitive challenges (Beta = .253, p= .013). After adjustment for respiratory rate, this effect became marginally significant (Beta = .177, p= .037). In contrast, for the relationship of trait anger to vagal recovery, this effect was not significant either before (Beta = .141, p=.257) or after (Beta = .186, p=.072) adjusting for respiratory rate. Secondary analyses revealed that among the individuals with higher levels of trait anxiety, greater reductions in perceived stress were associated with greater increases in cardiac vagal control after the challenge. In contrast, among the individuals with lower levels of trait anxiety, changes in perceived stress had no impact on vagal recovery. Therefore, change in perceived stress moderates the relationship of trait anxiety, but not trait anger, to vagal recovery from cognitive challenge. PMID:21945037

  20. The association between affective psychopathic traits, time incarcerated, and cortisol response to psychosocial stress.

    Science.gov (United States)

    Johnson, Megan M; Mikolajewski, Amy; Shirtcliff, Elizabeth A; Eckel, Lisa A; Taylor, Jeanette

    2015-06-01

    Previous research has demonstrated that psychopathic personality traits are significantly predictive of blunted cortisol reactivity to a performance-based stressor task (Trier Social Stress Test; TSST) in college students. However, the relationship between cortisol reactivity and psychopathy has not been explored in high risk samples such as incarcerated populations. Further, the role of imprisonment in relation to cortisol stress reactivity has not been previously explored, but could have practical and conceptual consequences in regard to rehabilitation and biological sensitivity to context, respectively. The current study tested the hypotheses that both psychopathic personality traits and amount of time incarcerated are related to cortisol blunting in response to stress among incarcerated young adults. A sample of 49 young adult male offenders was recruited to complete the TSST. Salivary hormone samples were taken just prior to and 20 min post-stressor, and participants were interviewed with the Psychopathy Checklist-Youth Version. Variables quantifying the amount of time at the present facility prior to the date of testing and number of commitments in juvenile facilities were also collected. Correlational analyses indicated that only number of incarcerations was related to blunted cortisol. Hierarchical Linear Modeling revealed that time incarcerated and number of commitments were related to a blunted cortisol response among responders and declining cortisol reactivity among nonresponders, respectively. Controlling for time incarcerated, psychopathic traits were significantly related to cortisol decline in response to the stressor among nonresponders, but were not related to blunted cortisol among responders. Results of this project highlight the potential biological effects of prolonged and repeated incarcerations, and extend our understanding about the relationship between psychopathic traits and cortisol reactivity in an incarcerated sample. Copyright © 2015

  1. IDENTIFICATION OF A MAJOR QUANTITATIVE TRAIT LOCUS CONFERRING RICE BLAST RESISTANCE USING RECOMBINANT INBRED LINES

    Directory of Open Access Journals (Sweden)

    Sobrizal Sobrizal

    2013-05-01

    Full Text Available Blast disease caused by Pyricularia oryzae is one of the limiting factors for rice production world wide. The use of resistant varieties for managing blast disease is considered as the most eco-friendly approaches. However, their resistances may be broken down within a few years due to the appearance of new virulent blast races in the field. The objective of the present study was to identify the quantitative trait locus (QTL conferring resistance to blast disease using 126 recombinant inbred (RI lines originated from a crossing of a durably resistant upland rice genotype (Laka and a highly susceptible rice accession cultivar (Kencana Bali. The RI population was developed through a single seed descent method from 1997 to 2004. Resistance of the RI lines was evaluated for blast in an endemic area of Sukabumi, West Java, in 2005. Disease intensity of the blast was examined following the standard evaluation system developed by the International Rice Research Institute (IRRI. At the same year the RI lines were analyzed with 134 DNA markers. Results of the study showed that one major QTL was found to be associated with blast resistance, and this QTL was located near RM2136 marker on the long arm of chromosome 11. This QTL explained 87% of the phenotypic variation with 37% additive effect. The map position of this QTL differed from that of a partial resistant gene, Pi34, identified previously on chromosome 11 in the Japanese durably resistant variety, Chubu 32. The QTL, however, was almost at the same position as that of the multiple allele-resistant gene, Pik. Therefore, an allelic test should be conducted to clarify the allelic relationship between QTL identified in this study and the Pik. The RI lines are the permanent segregating population that could be very useful for analysing phenotypic variations of important agronomic traits possibly owned by the RI lines. The major QTL identified in this study could be used as a genetic resource in

  2. Levels of salivary immunoglobulin A under psychological stress and its relationship with rumination and five personality traits in medical students

    OpenAIRE

    Reza Afrishama; Mohammad Aberomand; Omid SoliemaniFar; Wesam Kooti; Damoon Ashtary-Larky; Fatima Alamiri; Sedigheh Najjar-Asl; Ali Khaneh-Keshi; Sahar Sadegh-Nejadi

    2016-01-01

    Background and Objectives: The measurement of salivary immunoglobulin A is a useful and non-invasive method for measuring stress. Personality traits and rumination act as possible mediators in the relationship between psychological stressors and the immune system. This study was aimed to evaluate the levels of salivary IgA under psychological stress and its relationship with rumination and five personality traits in medical students. Methods: In this cross- sectional study, 45 medical student...

  3. Environmental Stress and Antibiotic Resistance in Food-Related Pathogens▿

    Science.gov (United States)

    McMahon, M. Ann S.; Xu, Jiru; Moore, John E.; Blair, Ian S.; McDowell, David A.

    2007-01-01

    This study investigated the possibility that sublethal food preservation stresses (high or low temperature and osmotic and pH stress) can lead to changes in the nature and scale of antibiotic resistance (ABR) expressed by three food-related pathogens (Escherichia coli, Salmonella enterica serovar Typhimurium, and Staphylococcus aureus). The study found that some sublethal stresses significantly altered antibiotic resistance. Incubation at sublethal high temperature (45°C) decreased ABR. Incubation under increased salt (>4.5%) or reduced pH (<5.0) conditions increased ABR. Some of the pathogens continued to express higher levels of ABR after removal of stress, suggesting that in some cases the applied sublethal stress had induced stable increases in ABR. These results indicate that increased use of bacteriostatic (sublethal), rather than bactericidal (lethal), food preservation systems may be contributing to the development and dissemination of ABR among important food-borne pathogens. PMID:17142359

  4. Progress in engineering acid stress resistance of lactic acid bacteria.

    Science.gov (United States)

    Wu, Chongde; Huang, Jun; Zhou, Rongqing

    2014-02-01

    Lactic acid bacteria (LAB) are widely used for the production of a variety of fermented foods, and are considered as probiotic due to their health-promoting effect. However, LAB encounter various environmental stresses both in industrial fermentation and application, among which acid stress is one of the most important survival challenges. Improving the acid stress resistance may contribute to the application and function of probiotic action to the host. Recently, the advent of genomics, functional genomics and high-throughput technologies have allowed for the understanding of acid tolerance mechanisms at a systems level, and many method to improve acid tolerance have been developed. This review describes the current progress in engineering acid stress resistance of LAB. Special emphasis is placed on engineering cellular microenvironment (engineering amino acid metabolism, introduction of exogenous biosynthetic capacity, and overproduction of stress response proteins) and maintaining cell membrane functionality. Moreover, strategies to improve acid tolerance and the related physiological mechanisms are also discussed.

  5. Effects of water stress on irradiance acclimation of leaf traits in almond trees.

    Science.gov (United States)

    Egea, Gregorio; González-Real, María M; Baille, Alain; Nortes, Pedro A; Conesa, María R; Ruiz-Salleres, Isabel

    2012-04-01

    Photosynthetic acclimation to highly variable local irradiance within the tree crown plays a primary role in determining tree carbon uptake. This study explores the plasticity of leaf structural and physiological traits in response to the interactive effects of ontogeny, water stress and irradiance in adult almond trees that have been subjected to three water regimes (full irrigation, deficit irrigation and rain-fed) for a 3-year period (2006-08) in a semiarid climate. Leaf structural (dry mass per unit area, N and chlorophyll content) and photosynthetic (maximum net CO(2) assimilation, A(max), maximum stomatal conductance, g(s,max), and mesophyll conductance, g(m)) traits and stem-to-leaf hydraulic conductance (K(s-l)) were determined throughout the 2008 growing season in leaves of outer south-facing (S-leaves) and inner northwest-facing (NW-leaves) shoots. Leaf plasticity was quantified by means of an exposure adjustment coefficient (ε=1-X(NW)/X(S)) for each trait (X) of S- and NW-leaves. Photosynthetic traits and K(s-l) exhibited higher irradiance-elicited plasticity (higher ε) than structural traits in all treatments, with the highest and lowest plasticity being observed in the fully irrigated and rain-fed trees, respectively. Our results suggest that water stress modulates the irradiance-elicited plasticity of almond leaves through changes in crown architecture. Such changes lead to a more even distribution of within-crown irradiance, and hence of the photosynthetic capacity, as water stress intensifies. Ontogeny drove seasonal changes only in the ε of area- and mass-based N content and mass-based chlorophyll content, while no leaf age-dependent effect was observed on ε as regards the physiological traits. Our results also indicate that the irradiance-elicited plasticity of A(max) is mainly driven by changes in leaf dry mass per unit area, in g(m) and, most likely, in the partitioning of the leaf N content.

  6. Role of trait shame in the association between posttraumatic stress and aggression among men with a history of interpersonal trauma.

    Science.gov (United States)

    Schoenleber, Michelle; Sippel, Lauren M; Jakupcak, Matthew; Tull, Matthew T

    2015-01-01

    Given the theoretical and empirical associations among posttraumatic stress, shame, and interpersonal aggression, this study examined whether trait shame accounts for the associations between posttraumatic stress and aggressive behavior in a sample of 103 men with a history of interpersonal trauma. Results indicated that trait shame accounted for the associations of posttraumatic stress with the variety of both physically and psychologically aggressive behavior, as well as with the frequency of physical aggression. This study also examined trait guilt, given its conceptual relationship to both shame and posttraumatic stress; unlike trait shame, trait guilt did not account for the association between posttraumatic stress and the variety of physically aggressive acts. Additionally, although trait guilt reduced the association between posttraumatic stress and the frequency of physical aggression, the indirect path including guilt was nonsignificant. Taken together, the present study supports existing theories suggesting that shame, but not guilt, may contribute to aggressive behavior, especially among individuals with histories of traumatic exposure. (c) 2015 APA, all rights reserved).

  7. Mapping of quantitative trait loci affecting resistance/susceptibility to Sarcocystis miescheriana in swine.

    Science.gov (United States)

    Reiner, Gerald; Kliemt, Damaris; Willems, Hermann; Berge, Thomas; Fischer, Reiner; Köhler, Florian; Hepp, Sabine; Hertrampf, Barbara; Daugschies, Arwid; Geldermann, Hermann; Mackenstedt, Ute; Zahner, Horst

    2007-05-01

    The outcome of infectious diseases in vertebrates is under genetic control at least to some extent. In swine, e.g., marked differences in resistance/susceptibility to Sarcocystis miescheriana have been shown between Chinese Meishan and European Pietrain pigs, and these differences are associated with high heritabilities. A first step toward the identification of genes and polymorphisms causal for these differences may be the mapping of quantitative trait loci (QTLs). Considering clinical, immunological, and parasitological traits in the above model system, this survey represents the first QTL study on parasite resistance in pigs. QTL mapping was performed in 139 F(2) pigs of a Meishan/Pietrain family infected with S. miescheriana. Fourteen genome-wide significant QTLs were mapped to several chromosomal areas. Among others, major QTLs were identified for bradyzoite numbers in skeletal muscles (F = 17.4; p < 0.001) and for S. miescheriana-specific plasma IgG(2) levels determined 42 days p.i. (F = 20.9; p < 0.001). The QTLs were mapped to different regions of chromosome 7, i.e., to the region of the major histocompatibility complex (bradyzoites) and to an immunoglobulin heavy chain cluster, respectively. These results provide evidence for a direct and causal role for gene variants within these gene clusters (cis-acting) in differences in resistance to S. miescheriana.

  8. Comparison of Leaf Sheath Transcriptome Profiles with Physiological Traits of Bread Wheat Cultivars under Salinity Stress.

    Directory of Open Access Journals (Sweden)

    Fuminori Takahashi

    Full Text Available Salinity stress has significant negative effects on plant biomass production and crop yield. Salinity tolerance is controlled by complex systems of gene expression and ion transport. The relationship between specific features of mild salinity stress adaptation and gene expression was analyzed using four commercial varieties of bread wheat (Triticum aestivum that have different levels of salinity tolerance. The high-throughput phenotyping system in The Plant Accelerator at the Australian Plant Phenomics Facility revealed variation in shoot relative growth rate and salinity tolerance among the four cultivars. Comparative analysis of gene expression in the leaf sheaths identified genes whose functions are potentially linked to shoot biomass development and salinity tolerance. Early responses to mild salinity stress through changes in gene expression have an influence on the acquisition of stress tolerance and improvement in biomass accumulation during the early "osmotic" phase of salinity stress. In addition, results revealed transcript profiles for the wheat cultivars that were different from those of usual stress-inducible genes, but were related to those of plant growth. These findings suggest that, in the process of breeding, selection of specific traits with various salinity stress-inducible genes in commercial bread wheat has led to adaptation to mild salinity conditions.

  9. Comparison of Leaf Sheath Transcriptome Profiles with Physiological Traits of Bread Wheat Cultivars under Salinity Stress

    KAUST Repository

    Takahashi, Fuminori

    2015-08-05

    Salinity stress has significant negative effects on plant biomass production and crop yield. Salinity tolerance is controlled by complex systems of gene expression and ion transport. The relationship between specific features of mild salinity stress adaptation and gene expression was analyzed using four commercial varieties of bread wheat (Triticum aestivum) that have different levels of salinity tolerance. The high-throughput phenotyping system in The Plant Accelerator at the Australian Plant Phenomics Facility revealed variation in shoot relative growth rate and salinity tolerance among the four cultivars. Comparative analysis of gene expression in the leaf sheaths identified genes whose functions are potentially linked to shoot biomass development and salinity tolerance. Early responses to mild salinity stress through changes in gene expression have an influence on the acquisition of stress tolerance and improvement in biomass accumulation during the early “osmotic” phase of salinity stress. In addition, results revealed transcript profiles for the wheat cultivars that were different from those of usual stress-inducible genes, but were related to those of plant growth. These findings suggest that, in the process of breeding, selection of specific traits with various salinity stress-inducible genes in commercial bread wheat has led to adaptation to mild salinity conditions.

  10. Comparison of Leaf Sheath Transcriptome Profiles with Physiological Traits of Bread Wheat Cultivars under Salinity Stress

    Science.gov (United States)

    Trittermann, Christine; Berger, Bettina; Roy, Stuart J.; Seki, Motoaki; Shinozaki, Kazuo; Tester, Mark

    2015-01-01

    Salinity stress has significant negative effects on plant biomass production and crop yield. Salinity tolerance is controlled by complex systems of gene expression and ion transport. The relationship between specific features of mild salinity stress adaptation and gene expression was analyzed using four commercial varieties of bread wheat (Triticum aestivum) that have different levels of salinity tolerance. The high-throughput phenotyping system in The Plant Accelerator at the Australian Plant Phenomics Facility revealed variation in shoot relative growth rate and salinity tolerance among the four cultivars. Comparative analysis of gene expression in the leaf sheaths identified genes whose functions are potentially linked to shoot biomass development and salinity tolerance. Early responses to mild salinity stress through changes in gene expression have an influence on the acquisition of stress tolerance and improvement in biomass accumulation during the early “osmotic” phase of salinity stress. In addition, results revealed transcript profiles for the wheat cultivars that were different from those of usual stress-inducible genes, but were related to those of plant growth. These findings suggest that, in the process of breeding, selection of specific traits with various salinity stress-inducible genes in commercial bread wheat has led to adaptation to mild salinity conditions. PMID:26244554

  11. Comparison of Leaf Sheath Transcriptome Profiles with Physiological Traits of Bread Wheat Cultivars under Salinity Stress.

    Science.gov (United States)

    Takahashi, Fuminori; Tilbrook, Joanne; Trittermann, Christine; Berger, Bettina; Roy, Stuart J; Seki, Motoaki; Shinozaki, Kazuo; Tester, Mark

    2015-01-01

    Salinity stress has significant negative effects on plant biomass production and crop yield. Salinity tolerance is controlled by complex systems of gene expression and ion transport. The relationship between specific features of mild salinity stress adaptation and gene expression was analyzed using four commercial varieties of bread wheat (Triticum aestivum) that have different levels of salinity tolerance. The high-throughput phenotyping system in The Plant Accelerator at the Australian Plant Phenomics Facility revealed variation in shoot relative growth rate and salinity tolerance among the four cultivars. Comparative analysis of gene expression in the leaf sheaths identified genes whose functions are potentially linked to shoot biomass development and salinity tolerance. Early responses to mild salinity stress through changes in gene expression have an influence on the acquisition of stress tolerance and improvement in biomass accumulation during the early "osmotic" phase of salinity stress. In addition, results revealed transcript profiles for the wheat cultivars that were different from those of usual stress-inducible genes, but were related to those of plant growth. These findings suggest that, in the process of breeding, selection of specific traits with various salinity stress-inducible genes in commercial bread wheat has led to adaptation to mild salinity conditions.

  12. Interaction between the RGS6 gene and psychosocial stress on obesity-related traits.

    Science.gov (United States)

    Kim, Hyun-Jin; Min, Jin-Young; Min, Kyoung-Bok

    2017-03-31

    Obesity is a major risk factor for chronic diseases and arises from the interactions between environmental factors and multiple genes. Psychosocial stress may affect the risk for obesity, modifying food intake and choice. A recent study suggested regulator of G-protein signaling 6 (RGS6) as a novel candidate gene for obesity in terms of reward-related feeding under stress. In this study, we tried to verify the unidentified connection between RGS6 and human obesity with psychosocial stress in a Korean population. A total of 1,462 adult subjects, who participated in the Korean Association Resource cohort project, were included for this analysis. Obesity-related traits including waist circumference, body mass index, and visceral adipose tissue were recorded. A total of 4 intronic SNPs for the RGS6 gene were used for this study. We found that interactions between SNP rs2239219 and psychosocial stress are significantly associated with abdominal obesity (p = 0.007). As risk allele of this SNP increased, prevalence of abdominal obesity under high-stress conditions gradually increased (p = 0.013). However, we found no SNPs-by-stress interaction effect on other adiposity phenotypes. This study suggests that RGS6 is closely linked to stress-induced abdominal obesity in Korean adults.

  13. Programming of Cell Resistance to Genotoxic and Oxidative Stress.

    Science.gov (United States)

    Velegzhaninov, Ilya O; Ievlev, Vitaly A; Pylina, Yana I; Shadrin, Dmitry M; Vakhrusheva, Olesya M

    2018-01-02

    Different organisms, cell types, and even similar cell lines can dramatically differ in resistance to genotoxic stress. This testifies to the wide opportunities for genetic and epigenetic regulation of stress resistance. These opportunities could be used to increase the effectiveness of cancer therapy, develop new varieties of plants and animals, and search for new pharmacological targets to enhance human radioresistance, which can be used for manned deep space expeditions. Based on the comparison of transcriptomic studies in cancer cells, in this review, we propose that there is a high diversity of genetic mechanisms of development of genotoxic stress resistance. This review focused on possibilities and limitations of the regulation of the resistance of normal cells and whole organisms to genotoxic and oxidative stress by the overexpressing of stress-response genes. Moreover, the existing experimental data on the effect of such overexpression on the resistance of cells and organisms to various genotoxic agents has been analyzed and systematized. We suggest that the recent advances in the development of multiplex and highly customizable gene overexpression technology that utilizes the mutant Cas9 protein and the abundance of available data on gene functions and their signal networks open new opportunities for research in this field.

  14. Field-Based High-Throughput Plant Phenotyping Reveals the Temporal Patterns of Quantitative Trait Loci Associated with Stress-Responsive Traits in Cotton.

    Science.gov (United States)

    Pauli, Duke; Andrade-Sanchez, Pedro; Carmo-Silva, A Elizabete; Gazave, Elodie; French, Andrew N; Heun, John; Hunsaker, Douglas J; Lipka, Alexander E; Setter, Tim L; Strand, Robert J; Thorp, Kelly R; Wang, Sam; White, Jeffrey W; Gore, Michael A

    2016-04-07

    The application of high-throughput plant phenotyping (HTPP) to continuously study plant populations under relevant growing conditions creates the possibility to more efficiently dissect the genetic basis of dynamic adaptive traits. Toward this end, we employed a field-based HTPP system that deployed sets of sensors to simultaneously measure canopy temperature, reflectance, and height on a cotton (Gossypium hirsutum L.) recombinant inbred line mapping population. The evaluation trials were conducted under well-watered and water-limited conditions in a replicated field experiment at a hot, arid location in central Arizona, with trait measurements taken at different times on multiple days across 2010-2012. Canopy temperature, normalized difference vegetation index (NDVI), height, and leaf area index (LAI) displayed moderate-to-high broad-sense heritabilities, as well as varied interactions among genotypes with water regime and time of day. Distinct temporal patterns of quantitative trait loci (QTL) expression were mostly observed for canopy temperature and NDVI, and varied across plant developmental stages. In addition, the strength of correlation between HTPP canopy traits and agronomic traits, such as lint yield, displayed a time-dependent relationship. We also found that the genomic position of some QTL controlling HTPP canopy traits were shared with those of QTL identified for agronomic and physiological traits. This work demonstrates the novel use of a field-based HTPP system to study the genetic basis of stress-adaptive traits in cotton, and these results have the potential to facilitate the development of stress-resilient cotton cultivars. Copyright © 2016 Pauli et al.

  15. Effects of natural stress relief meditation on trait anxiety: a pilot study.

    Science.gov (United States)

    Coppola, Fabrizio

    2007-08-01

    Natural Stress Relief meditation, a mental technique which is practiced for 15 minutes twice a day, aims to reduce stress and anxiety by eliciting a specific state of physiological rest along with mental alertness. The meditation is taught in a self-administered program, requiring one hour of training during the first three days, followed by the regular twice daily practice. Each 15-min. session consists in sitting quietly with closed eyes while applying a specific mental procedure. To test the effectiveness of meditation in reducing trait anxiety, Spielberger's State-Trait Anxiety Inventory was administered to 25 participants four times over a 3-wk. period: one week before starting to practice the meditation, a few hours before starting, 1 wk. after, and 2 wk. after. The difference in Trait Anxiety score between pretreatment and before starting the practice was not significant, while it was significant both after the first week of practice (Cohen d=.46) and after the first 2 wk. of practice (d=.67).

  16. Emotions and stress increase respiratory resistance in asthma.

    Science.gov (United States)

    Ritz, T; Steptoe, A; DeWilde, S; Costa, M

    2000-01-01

    Clinical reports suggest that various emotions and types of stress can precipitate asthmatic symptoms, but there is little experimental evidence to substantiate this claim. We studied the impact of different emotional states and stress on respiratory resistance in asthmatic and nonasthmatic individuals. Participants (24 asthmatic and 24 nonasthmatic patients) viewed short film sequences selected to induce anxiety, anger, depression, elation, happiness, contentment, or a neutral affective state and completed two stressful tasks, mental arithmetic to induce active coping efforts and viewing of medical slides to induce passive coping efforts. Oscillatory resistance, heart rate, blood pressure, baroreflex sensitivity, skin conductance level, respiration rate and volume, and self-reported affective state were measured throughout the session. Uniform increases in oscillatory resistance were found in all emotional states compared with the neutral state and during mental arithmetic in both groups. Asthmatic patients showed stronger reactions to the medical slides than healthy control subjects, with significant increases in oscillatory resistance, blood pressure, skin conductance level, and minute volume, as well as higher levels of self-reported depression, arousal, and shortness of breath. Changes in oscillatory resistance were inconsistently correlated with other physiological indices. Various emotional states and stress increase oscillatory resistance largely independently of concurrent increases in autonomic or ventilatory activity. The particular sensitivity of asthmatics to passive coping demand requires additional research.

  17. Evaluation of Snap Bean Genotypes Combining Rust Resistance and Heat Tolerance Traits in East Africa

    Science.gov (United States)

    The major biotic and abiotic constraints to snap bean production in East Africa include diseases such as common bean rust (caused by Uromyces appendiculatus) and high ambient temperatures that cause heat stress. Rust resistant snap beans that perform well under both cool and hot agro-ecological cond...

  18. Occupational stress and personality traits in multiple sclerosis: A preliminary study.

    Science.gov (United States)

    Concetta Incerti, Chiara; Magistrale, Giuseppe; Argento, Ornella; Pisani, Valerio; Di Battista, Giancarlo; Ferraro, Elisabetta; Caltagirone, Carlo; Benedict, Ralph H B; Nocentini, Ugo

    2015-07-01

    Multiple Sclerosis (MS) is a demyelinating and neurodegenerative disease of the central nervous system, causing a wide range of neurological and psychological symptoms. Impairment of ambulation and cognition in particular are associated with work difficulties and unemployment. Although many aspects of work status have been investigated in MS, there are no reports on factors that predict the development of occupational stress, prior to job loss. The aim of this preliminary study was to ascertain if personality traits predispose MS patients to occupational stress. We evaluated 26 MS patients using physical disability scales and self-report questionnaires focused on mood, fatigue, and personality [measured with the NEO Five Factor Inventory]. The primary outcome measure was the Occupational Stress Indicator [OSI]. Results showed significant positive correlations (ppersonality dispositions in the hope that employment may be maintained. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Pleiotropic morphological and abiotic stress resistance phenotypes ...

    Indian Academy of Sciences (India)

    Unknown

    mutant was salinity and water-stress tolerant. The abscisic acid (ABA) content in the leaves was about 500-fold higher. The genetic lesion abo responsible for the above pleiotropy was recessive and inherited in Mendelian fashion. The seedlings and adult plants of the mutant accumulated higher proline than Abo+ plants.

  20. Studying correlation and regression equations between traits of grain corn under different fertilizer combinations and drought stress condition

    Directory of Open Access Journals (Sweden)

    M Zarabi

    2016-05-01

    Full Text Available In order to study the combined and separate effects of phosphorus fertilizer, phosphate-solubilizing bacteria and mycorrhizal fungus on adjusting and reducing the loss of yield resulting from drought stress during the stage of growth of grain corn (SC704 an experiment was performed in Aboureihan Campus of the University of Tehran, Iran, during 2007-2008. The experiment was conducted as split plot based on a randomised completely block design (RCBD with four replications. Experimental factors were drought stress as the main-plot [irrigation after 50 [without drought stress], 100 and 150 mm evaporation from pan class A, and fertilizer compounds as the sub-plot (100% phosphorus (b5, 50% super phosphate triple+ mycorrhizal fungus + Phosphate-solubilizing bacteria (b2, mycorrhizal fungus + Phosphate-solubilizing bacteria (b1, 50% super phosphate triple + Phosphate-solubilizing bacteria (b3, and 50% super phosphate triple + mycorrhizal fungus (b4. Drought stress happened after seedling establishment. Result of variance analysis showed that drought stress significantly affected plant height, stem dry weight, stem diameter, ear height, kernel number per row, 300 kernel weight, ear weight, ear length, ear diameter, cob diameter, kernel depth, cob percentage and total yield traits. Also, there was not significantly difference between fertilizer treatment for number of Leaf per plant, stem diameter and ear height traits. All the assessed traits in b2 inoculated treatment showed of higher values than other treats under water deficit stress condition. Furthermore, the investigated traits of b5 treat under severe water deficit stress were significantly less pronounced than normal irrigation and low stressed conditions. The results showed that all measured traits in seed inoculums with b2 under the low drought stress stood higher than other treats. Using stepwise regression was performed for grain corn in all conditions and in high stress conditions four

  1. The influence of personality traits and social support on male nursing student life stress: a cross-sectional research design.

    Science.gov (United States)

    Lou, Jiunn-Horng; Chen, Sheng-Hwang; Yu, Hsing-Yi; Li, Ren-Hau; Yang, Cheng-I; Eng, Cheng-Joo

    2010-06-01

    Understanding how male nursing students alleviate life stress during their academic career is conducive to their development as successful nursing professionals. This study was designed to understand the personality traits, social support, and life stresses of male nursing students. The respective influences of personality traits and social support on life stress were also explored. The study used a cross-sectional research design. A college in central Taiwan was targeted as the site for data collection. A total of 158 questionnaires were dispatched, with 145 valid copies returned (valid response rate = 91.7%). Structured questionnaires were designed to collect data on participant demographics, personality traits, social support, and life stress. Statistical methods such as descriptive statistics, one-way analysis of variance, and multiple regression analysis were applied to data analysis. Major findings of this study revealed that (a) in general, the personality traits, social support, and life stress of male nursing students scored in the medium to high range. Participants reported encountering more stress from learning and life goals than from interpersonal stress. (b) Male nursing student demographic variables (e.g., parent [father and mother considered separately] education level) and the personality traits of conscientiousness and family support, respectively, were found to impact significantly on participant life stress perceptions. And (c) the only significant predictors of life stress were support from family and education level of participant fathers and mothers, accounting for about 23.7% of variability. It is suggested that nursing students in each year of their academic career should be exposed to courses geared to reduce the life stress perceptions (especially in the areas of learning and career development) of male nursing students. Increased family support is an effective way to decrease male nursing student life stress. This study could be a

  2. [Significance of pain sensitivity for the resistance to immobilization stress].

    Science.gov (United States)

    Zarubina, I V; Shabanov, P D

    2012-01-01

    The effects of immobilization stress (immobilization on back within 4 h) on the functional indexes of Wistar male rats differing with pain sensitivity in the tail-flick test were studied. The acute immobilization stress in rats with high pain sensitivity compared with low pain sensitivity animals produced the most changes of the main functional systems. The high pain sensitivity rats demonstrated more significant hypotension, bradicardia, temperature shift, decrease of breath frequency and oxygen consumption, acid-alkaline equilibrium disorders with lactate acidosis signs. Therefore, the rats with low pain sensitivity possess the high resistance to acute stress exposure in comparison with high pain sensitivity animals. This confirms the important significance of individual pain sensitivity for the formation of stress resistance.

  3. [Influence of affectivity trait on relationships between occupational stress and subjective physical health and job satisfaction].

    Science.gov (United States)

    Yu, Shan-fa; Zhou, Wen-hui; Gu, Gui-zhen

    2008-09-01

    To explore the influence of affectivity trait on relationships between occupational stress and subjective physical health and job satisfaction. Self-reports for psychosocial work conditions and health and well-being in a sample of 878 workers from a thermal power plant in China were conducted using the job demand-control model, the effort-reward imbalance model, job satisfaction, depression symptom, and physical health complaints questionnaires. Logistic regression analysis was used by controlling for age, sex, and educational level. Negative and positive affectivity were correlated with occupational stressors or strains (Paffectivity or positive affectivity was controlled; Odds ratios decreased greater when negative affectivity and positive affectivity were controlled simultaneously. Furthermore in some equation no variable entered. Affectivity trait has effect on relationships between occupational stress and subjective physical health and job satisfaction. According to the outcome category of study, the possible confounding role of affectivity should be controlled in the study of the relationships between occupational stress and health self-reports.

  4. Prenatal maternal stress predicts autism traits in 6½ year-old children: Project Ice Storm.

    Science.gov (United States)

    Walder, Deborah J; Laplante, David P; Sousa-Pires, Alexandra; Veru, Franz; Brunet, Alain; King, Suzanne

    2014-10-30

    Research implicates prenatal maternal stress (PNMS) as a risk factor for neurodevelopmental disorders; however few studies report PNMS effects on autism risk in offspring. We examined, prospectively, the degree to which objective and subjective elements of PNMS explained variance in autism-like traits among offspring, and tested moderating effects of sex and PNMS timing in utero. Subjects were 89 (46F/43M) children who were in utero during the 1998 Quebec Ice Storm. Soon after the storm, mothers completed questionnaires on objective exposure and subjective distress, and completed the Autism Spectrum Screening Questionnaire (ASSQ) for their children at age 6½. ASSQ scores were higher among boys than girls. Greater objective and subjective PNMS predicted higher ASSQ independent of potential confounds. An objective-by-subjective interaction suggested that when subjective PNMS was high, objective PNMS had little effect; whereas when subjective PNMS was low, objective PNMS strongly affected ASSQ scores. A timing-by-objective stress interaction suggested objective stress significantly affected ASSQ in first-trimester exposed children, though less so with later exposure. The final regression explained 43% of variance in ASSQ scores; the main effect of sex and the sex-by-PNMS interactions were not significant. Findings may help elucidate neurodevelopmental origins of non-clinical autism-like traits from a dimensional perspective. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Next generation sequencing of Apis mellifera syriaca identifies genes for Varroa resistance and beneficial bee keeping traits.

    Science.gov (United States)

    Haddad, Nizar; Mahmud Batainh, Ahmed; Suleiman Migdadi, Osama; Saini, Deepti; Krishnamurthy, Venkatesh; Parameswaran, Sriram; Alhamuri, Zaid

    2016-08-01

    Apis mellifera syriaca exhibits a high degree of tolerance to pests and pathogens including varroa mites. This native honey bee subspecies of Jordan expresses behavioral adaptations to high temperature and dry seasons typical of the region. However, persistent honey bee imports of commercial breeder lines are endangering local honey bee population. This study reports the use of next-generation sequencing (NGS) technology to study the A. m. syriaca genome and to identify genetic factors possibly contributing toward mite resistance and other favorable traits. We obtained a total of 46.2 million raw reads by applying the NGS to sequence A. m. syriaca and used extensive bioinformatics approach to identify several candidate genes for Varroa mite resistance, behavioral and immune responses characteristic for these bees. As a part of characterizing the functional regulation of molecular genetic pathway, we have mapped the pathway genes potentially involved using information from Drosophila melanogaster and present possible functional changes implicated in responses to Varroa destructor mite infestation toward this. We performed in-depth functional annotation methods to identify ∼600 candidates that are relevant, genes involved in pathways such as microbial recognition and phagocytosis, peptidoglycan recognition protein family, Gram negative binding protein family, phagocytosis receptors, serpins, Toll signaling pathway, Imd pathway, Tnf, JAK-STAT and MAPK pathway, heamatopioesis and cellular response pathways, antiviral, RNAi pathway, stress factors, etc. were selected. Finally, we have cataloged function-specific polymorphisms between A. mellifera and A. m. syriaca that could give better understanding of varroa mite resistance mechanisms and assist in breeding. We have identified immune related embryonic development (Cactus, Relish, dorsal, Ank2, baz), Varroa hygiene (NorpA2, Zasp, LanA, gasp, impl3) and Varroa resistance (Pug, pcmt, elk, elf3-s10, Dscam2, Dhc64C, gro

  6. Virulence traits and antibiotic resistance among enterococci isolated from dogs with periodontal disease.

    Science.gov (United States)

    Oliveira, Manuela; Tavares, Marta; Gomes, Diana; Touret, Tiago; São Braz, Berta; Tavares, Luís; Semedo-Lemsaddek, Teresa

    2016-06-01

    Periodontal disease - PD - is one of the most widespread diseases in dogs, but the role of this odontogenic infection in the dissemination of pathogenic bacteria present in the oral mucosa to other animals or pet owners is understudied. Trying to unveil the putative pathogenicity of enterococci present in the gums of dogs diagnosed with PD, thirty-two animals were investigated during routine visits to a private veterinary clinic. Seventy-one enterococci were recovered and characterized regarding species, genomic variability, virulence traits, antimicrobial resistance and biofilm-forming ability. Isolates were mainly identified as Enterococcus faecalis, with the large majority (95%) being able to produce biofilm. Regarding antibiotic resistance, all dog-enterococci were susceptible to ampicillin, amoxicillin/clavulanate, gentamicin-120, imipenem and vancomycin; while distinct levels of resistance were observed for chloramphenicol (10%), erythromycin (20%), streptomycin-300 (35%) and tetracycline (95%). For virulence traits incidence levels of 35% were observed for β-hemolysis and 25% for cylA, 25% for gelatinase and 35% for gelE; 85% harbor efaAfs and ebpABC; while ace, agg and esp are present respectively in 50, 30 and 10% of the dog-enterococci; efaAfm and acm were detected in all the Enterococcus faecium. Overall, the widespread prevalence of PD in dogs, associated with the close contact between companion animals, other animals and humans, may act as source for the dissemination of opportunistic pathogenic bacteria. Hence, aforementioned data on virulence and resistance features, emphasizes the need for active surveillance measures, such as the diagnose of PD in companion animals during routine visits to the veterinary clinic. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. An evolutionary comparative scan for longevity-related oxidative stress resistance mechanisms in homeotherms.

    Science.gov (United States)

    Pamplona, Reinald; Barja, Gustavo

    2011-10-01

    Key mechanisms relating oxidative stress to longevity from an interespecies comparative approach are reviewed. Long-lived animal species show low rates of reactive oxygen species (ROS) generation and oxidative damage at their mitochondria. Comparative physiology also shows that the specific compositional pattern of tissue macromolecules (proteins, lipids and nucleic acids) in long-lived animal species gives them an intrinsically high resistance to modification that likely contributes to their superior longevity. This is obtained in the case of lipids by decreasing the degree of fatty acid unsaturation, and in the case of proteins by lowering their methionine content. These findings are also substantiated from a phylogenomic approach. Nutritional or/and pharmacological interventions focused to modify some of these molecular traits were translated with modifications in animal longevity. It is proposed that natural selection tends to decrease the mitochondrial ROS generation and to increase the molecular resistance to the oxidative damage in long-lived species.

  8. Pre-cold stress increases acid stress resistance and induces amino ...

    African Journals Online (AJOL)

    Pre-cold stress increases acid stress resistance and induces amino acid homeostasis in Lactococcus lactis. NZ9000. Taher Khakpour Moghaddam1,2, Juan Zhang1,2, Guocheng Du1,2*. 1Key Laboratory of Industrial Biotechnology, Ministry of Education, 2School of Biotechnology, Jiangnan University, Wuxi,. Jiangsu ...

  9. Intermittent hypoxic resistance training: is metabolic stress the key moderator?

    Science.gov (United States)

    Scott, Brendan R; Slattery, Katie M; Dascombe, Ben J

    2015-02-01

    Traditionally, researchers and practitioners have manipulated acute resistance exercise variables to elicit the desired responses to training. However, recent research indicates that altering the muscular environment during resistance training, namely by implementing a hypoxic stimulus, can augment muscle hypertrophy and strength. Intermittent hypoxic resistance training (IHRT), whereby participants inspire hypoxic air during resistance training, has been previously demonstrated to increase muscle cross-sectional area and maximum strength by significantly greater amounts than the equivalent training in normoxia. However, some recent evidence has provided conflicting results, reporting that the use of systemic hypoxia during resistance training provided no added benefit. While the definitive mechanisms that may augment muscular responses to IHRT are not yet fully understood, an increased metabolic stress is thought to be important for moderating many downstream processes related to hypertrophy. It is likely that methodological differences between conflicting IHRT studies have resulted in different degrees of metabolic stress during training, particularly when considering the inter-set recovery intervals used. Given that the most fundamental physiological stresses resulting from hypoxia are disturbances to oxidative metabolism, it becomes apparent that resistance training may only benefit from additional hypoxia if the exercise is structured to elicit a strong metabolic response. We hypothesize that for IHRT to be more effective in producing muscular hypertrophy and increasing strength than the equivalent normoxic training, exercise should be performed with relatively brief inter-set recovery periods, with the aim of providing a potent metabolic stimulus to enhance anabolic responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Quantitative trait loci for resistance to trichostrongylid infection in Spanish Churra sheep

    Directory of Open Access Journals (Sweden)

    Primitivo Fermin San

    2009-10-01

    Full Text Available Abstract Background For ruminants reared on grazing systems, gastrointestinal nematode (GIN parasite infections represent the class of diseases with the greatest impact on animal health and productivity. Among the many possible strategies for controlling GIN infection, the enhancement of host resistance through the selection of resistant animals has been suggested by many authors. Because of the difficulty of routinely collecting phenotypic indicators of parasite resistance, information derived from molecular markers may be used to improve the efficiency of classical genetic breeding. Methods A total of 181 microsatellite markers evenly distributed along the 26 sheep autosomes were used in a genome scan analysis performed in a commercial population of Spanish Churra sheep to detect chromosomal regions associated with parasite resistance. Following a daughter design, we analysed 322 ewes distributed in eight half-sib families. The phenotypes studied included two faecal egg counts (LFEC0 and LFEC1, anti-Teladorsagia circumcincta LIV IgA levels (IgA and serum pepsinogen levels (Peps. Results The regression analysis revealed one QTL at the 5% genome-wise significance level on chromosome 6 for LFEC1 within the marker interval BM4621-CSN3. This QTL was found to be segregating in three out of the eight families analysed. Four other QTL were identified at the 5% chromosome-wise level on chromosomes 1, 10 and 14. Three of these QTL influenced faecal egg count, and the other one had an effect on IgA levels. Conclusion This study has successfully identified segregating QTL for parasite resistance traits in a commercial population. For some of the QTL detected, we have identified interesting coincidences with QTL previously reported in sheep, although most of those studies have been focused on young animals. Some of these coincidences might indicate that some common underlying loci affect parasite resistance traits in different sheep breeds. The

  11. Rec-8 dimorphism affects longevity, stress resistance and X-chromosome nondisjunction in C. elegans, and replicative lifespan in yeast

    Directory of Open Access Journals (Sweden)

    Srinivas eAyyadevara

    2014-08-01

    Full Text Available A quantitative trait locus (QTL in the nematode C. elegans, lsq4, was recently implicated by mapping longevity genes. QTLs for lifespan and 3 stress-resistance traits coincided within a span of <300 kbp, later narrowed to <200 kbp. A single gene in this interval is now shown to modulate all lsq4-associated traits. Full-genome analysis of transcript levels indicates that lsq4 contains a dimorphic gene governing expression of sperm-specific genes, suggesting effects on spermatogenesis. Quantitation of allele-specific transcripts encoded within the lsq4 interval revealed significant, 2- to 15-fold expression differences for 10 of 33 genes. Fourteen genes, implicated by both position and expression, were tested for RNA-interference effects on QTL-linked traits. In a strain carrying the shorter-lived allele, knockdown of rec-8 (encoding a meiotic cohesin reduced its transcripts 4-fold, to a level similar to the longer-lived strain, and extended lifespan 25–26% whether begun before fertilization or at maturity. The short-lived lsq4 allele also conferred sensitivity to oxidative and thermal stresses, and lower male frequency, traits reversed uniquely by rec-8 knockdown. A strain bearing the longer-lived lsq4 allele, differing from the short-lived strain at <0.3% of its genome, derived no lifespan or stress-survival benefit from rec-8 knockdown. We consider two possible explanations: high rec-8 expression may include increased leaky expression in mitotic cells, leading to deleterious destabilization of somatic genomes; or REC-8 may act entirely in germ-line meiotic cells to reduce aberrations such as nondisjunction, thereby blunting a stress-resistance response mediated by innate immunity. Replicative lifespan was extended 20% in haploid S. cerevisiae (BY4741 by deletion of REC8, orthologous to nematode rec-8, implying that REC8 disruption of mitotic-cell survival is widespread, reflecting antagonistic pleiotropy and/or balancing selection.

  12. Saccharomyces cerevisiae: population divergence and resistance to oxidative stress in clinical, domesticated and wild isolates.

    Directory of Open Access Journals (Sweden)

    Stephanie Diezmann

    Full Text Available BACKGROUND: Saccharomyces cerevisiae has been associated with human life for millennia in the brewery and bakery. Recently it has been recognized as an emerging opportunistic pathogen. To study the evolutionary history of S. cerevisiae, the origin of clinical isolates and the importance of a virulence-associated trait, population genetics and phenotypic assays have been applied to an ecologically diverse set of 103 strains isolated from clinics, breweries, vineyards, fruits, soil, commercial supplements and insect guts. METHODOLOGY/PRINCIPAL FINDINGS: DNA sequence data from five nuclear DNA loci were analyzed for population structure and haplotype distribution. Additionally, all strains were tested for survival of oxidative stress, a trait associated with microbial pathogenicity. DNA sequence analyses identified three genetic subgroups within the recombining S. cerevisiae strains that are associated with ecology, geography and virulence. Shared alleles suggest that the clinical isolates contain genetic contribution from the fruit isolates. Clinical and fruit isolates exhibit high levels of recombination, unlike the genetically homogenous soil isolates in which no recombination was detected. However, clinical and soil isolates were more resistant to oxidative stress than any other population, suggesting a correlation between survival in oxidative stress and yeast pathogenicity. CONCLUSIONS/SIGNIFICANCE: Population genetic analyses of S. cerevisiae delineated three distinct groups, comprising primarily the (i human-associated brewery and vineyard strains, (ii clinical and fruit isolates (iii and wild soil isolates from eastern U.S. The interactions between S. cerevisiae and humans potentiate yeast evolution and the development of genetically, ecologically and geographically divergent groups.

  13. Saccharomyces cerevisiae: population divergence and resistance to oxidative stress in clinical, domesticated and wild isolates.

    Science.gov (United States)

    Diezmann, Stephanie; Dietrich, Fred S

    2009-01-01

    Saccharomyces cerevisiae has been associated with human life for millennia in the brewery and bakery. Recently it has been recognized as an emerging opportunistic pathogen. To study the evolutionary history of S. cerevisiae, the origin of clinical isolates and the importance of a virulence-associated trait, population genetics and phenotypic assays have been applied to an ecologically diverse set of 103 strains isolated from clinics, breweries, vineyards, fruits, soil, commercial supplements and insect guts. DNA sequence data from five nuclear DNA loci were analyzed for population structure and haplotype distribution. Additionally, all strains were tested for survival of oxidative stress, a trait associated with microbial pathogenicity. DNA sequence analyses identified three genetic subgroups within the recombining S. cerevisiae strains that are associated with ecology, geography and virulence. Shared alleles suggest that the clinical isolates contain genetic contribution from the fruit isolates. Clinical and fruit isolates exhibit high levels of recombination, unlike the genetically homogenous soil isolates in which no recombination was detected. However, clinical and soil isolates were more resistant to oxidative stress than any other population, suggesting a correlation between survival in oxidative stress and yeast pathogenicity. Population genetic analyses of S. cerevisiae delineated three distinct groups, comprising primarily the (i) human-associated brewery and vineyard strains, (ii) clinical and fruit isolates (iii) and wild soil isolates from eastern U.S. The interactions between S. cerevisiae and humans potentiate yeast evolution and the development of genetically, ecologically and geographically divergent groups.

  14. Trait specific expression profiling of salt stress responsive genes in diverse rice genotypes as determined by modified Significance Analysis of Microarrays

    Directory of Open Access Journals (Sweden)

    Mohammad Rashed Hossain

    2016-05-01

    Full Text Available Stress responsive gene expression is commonly profiled in a comparative manner involving different stress conditions or genotypes with contrasting reputation of tolerance/resistance. In contrast, this research exploited a wide natural variation in terms of taxonomy, origin and salt sensitivity in eight genotypes of rice to identify the trait specific patterns of gene expression under salt stress. Genome wide transcptomic responses were interrogated by the weighted continuous morpho-physiological trait responses using modified Significance Analysis of Microarrays. More number of genes was found to be differentially expressed under salt stressed compared to that of under unstressed conditions. Higher numbers of genes were observed to be differentially expressed for the traits shoot Na+/K+, shoot Na+, root K+, biomass and shoot Cl-, respectively. The results identified around sixty genes to be involved in Na+, K+ and anion homeostasis, transport and transmembrane activity under stressed conditions. Gene Ontology (GO enrichment analysis identified 1.36% (578 genes of the entire transcriptome to be involved in the major molecular functions such as signal transduction (>150 genes, transcription factor (81 genes and translation factor activity (62 genes etc. under salt stress. Chromosomal mapping of the genes suggests that majority of the genes are located on chromosomes 1, 2, 3, 6 & 7. The gene network analysis showed that the transcription factors and translation initiation factors formed the major gene networks and are mostly active in nucleus, cytoplasm and mitochondria whereas the membrane and vesicle bound proteins formed a secondary network active in plasma membrane and vacuoles. The novel genes and the genes with unknown functions thus identified provide picture of a synergistic salinity response representing the potentially fundamental mechanisms that are active in the wide natural genetic background of rice and will be of greater use once

  15. Oxidative stress survival in a clinical Saccharomyces cerevisiae isolate is influenced by a major quantitative trait nucleotide.

    Science.gov (United States)

    Diezmann, Stephanie; Dietrich, Fred S

    2011-07-01

    One of the major challenges in characterizing eukaryotic genetic diversity is the mapping of phenotypes that are the cumulative effect of multiple alleles. We have investigated tolerance of oxidative stress in the yeast Saccharomyces cerevisiae, a trait showing phenotypic variation in the population. Initial crosses identified that this is a quantitative trait. Microorganisms experience oxidative stress in many environments, including during infection of higher eukaryotes. Natural variation in oxidative stress tolerance is an important aspect of response to oxidative stress exerted by the human immune system and an important trait in microbial pathogens. A clinical isolate of the usually benign yeast S. cerevisiae was found to survive oxidative stress significantly better than the laboratory strain. We investigated the genetic basis of increased peroxide survival by crossing those strains, phenotyping 1500 segregants, and genotyping of high-survival segregants by hybridization of bulk and single segregant DNA to microarrays. This effort has led to the identification of an allele of the transcription factor Rds2 as contributing to stress response. Rds2 has not previously been associated with the survival of oxidative stress. The identification of its role in the oxidative stress response here is an example of a specific trait that appears to be beneficial to Saccharomyces cerevisiae when growing as a pathogen. Understanding the role of this fungal-specific transcription factor in pathogenicity will be important in deciphering how fungi infect and colonize the human host and could eventually lead to a novel drug target.

  16. Association between the Five Factor personality traits and perceived stress: is the effect mediated by general self-efficacy?

    DEFF Research Database (Denmark)

    Ebstrup, Jeanette Frost; Eplov, Lene Falgaard; Pisinger, Charlotta

    2011-01-01

    Ill-health resulting from chronic stress is influenced by personality traits leading to different ways of appraising and coping with life's daily hassles. Using a large population sample the study aimed to investigate possible associations between perceived stress and the personality dimensions...

  17. Study of the genetic traits associated with antibiotic resistance in Staphylococcus aureus isolated from skin wards of Khyber Pakhtunkhwa, Pakistan

    Directory of Open Access Journals (Sweden)

    Saeed Ullah Khattak

    2015-05-01

    Full Text Available Objective: To investigate the prevalence of Staphylococcus aureus (S. aureus isolated from skin wards of the hospitals of Khyber Pakhtunkhwa, its resistance against various commonly and commercially available antibiotics, as well as different genetic traits of resistance and their correlations with the phenotypic visible resistance. Methods: In the present study a simple PCR technique were used to investigate the genetic traits of resistance in S. aureus isolated from skin wards of two major hospitals of Khyber Pakhtunkhwa, Pakistan. A total of 100 samples were collected from both the male and female, of which 50 were from patient’s site of infection and 50 from ward environment. Results: These results demonstrated that the total prevalence of S. aureus both in ward as well as in patients was 48%. The S. aureus prevalence was the highest in female patients (50% followed by ward environment (29% and then male patients (21%. The antibiotic sensitivity tests revealed that the highest (91.6% isolates sensitivity was shown to imipenem. However, the highest resistance was found to be against penicillin (100% isolates followed by cefotaxime (75% isolates. In addition, only 29% of the isolates were found to be resistant to methicillin. PCR technique based on the previously designed primers targeting different genetic traits of resistance revealed that 13 out of the 14 isolates resistant to methicillin were positive for mecA gene. blaZ Genetic traits were found in all isolates resistant to penicillin. The multidrug resistance traits, vgaA and vgaB each was detected only in 12.5% of S. aureus isolates. The phenotypic character of antibiotic resistance is highly correlated to different genetic traits of resistance. Conclusions: Based on our findings, it is concluded that antibiotic resistance in S. aureus strains is increasing day by day due to self-medications and medication by non-registered medical practitioners. Therefore, for quick and fast

  18. Comorbid psychopathology and stress mediate the relationship between autistic traits and repetitive behaviours in adults with autism.

    Science.gov (United States)

    García-Villamisar, D; Rojahn, J

    2015-02-01

    Comorbid psychopathology and stress were considered possible mediators that may explain the relationship between some autistic traits and repetitive behaviours. The current study sought to examine the mediational effects of comorbid psychopathology, executive dysfunctions and stress in the relationship between some autistic traits and repetitive behaviours. A battery of questionnaires including measures of autistic traits, repetitive behaviours, stress, executive dysfunctions and comorbid psychopathology were administered to a sample of adults with autism and intellectual disabilities (n = 43). We found that when taken as set dimensions of comorbidity, dysexecutive functioning and stress mediated or explained the effects of autistic symptoms on repetitive behaviour. The total model explained 60% of the variation in repetitive behaviours (R = 0.60; F = 13.64, P autism, while executive functioning did not contribute to that relationship. © 2013 2013 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

  19. Phenotypic Stability of Zea mays Grain Yield and Its Attributing Traits under Drought Stress.

    Science.gov (United States)

    Ali, Fawad; Ahsan, Muhammad; Ali, Qurban; Kanwal, Naila

    2017-01-01

    Phenotypic stability under stress environment facilitate the fitness of genotype and opens new horizons to explore the cryptic genetic variation. Variation in tolerance to drought stress, a major grain yield constraint to global maize production, was identified, at the phenotypic and genotypic level. Here we found a prominent hybrid H9 that showed fitness over four growing seasons for grain yield under water stress conditions. Genotypic and phenotypic correlation of yield attributing traits over four seasons demonstrated that cobs per plant, 100 seed weight, number of grains rows per cob, total dry matter, cob diameter had positive association (r(2) = 0.3-0.9) to grain yield. The perturbation was found for chlorophyll content as it showed moderate to strong association (P yield was found in H9 over four consecutive crop growing seasons. Combined analysis over four seasons showed that studied variables together explained 85% of total variation in dependent structure (grain yield) obtained by Principal component analysis. This significant finding is the best example of phenotypic stability of grain yield in H9 and made it best fitted for grain yield under drought stress scenario. Detailed genetic analysis of H9 will help us to identify significant loci and alleles that made H9 the best fitted and it could serve as a potential source to generate novel transgressive levels of tolerance for drought stress in arid/semiarid regions.

  20. Stress, abdominal obesity and intrarenal resistive index in essential hypertension.

    Science.gov (United States)

    Trovato, G M; Pace, P; Martines, G F; Trovato, F M; Pirri, C; Catalano, D

    2012-07-01

    Although it is commonly believed that a strong causal link exists between psychological stress and hypertension, as well with other factors, such as obesity, just what kind of empirical evidence supports this assumption is still controversial. The aim of the study is to investigate if perceived stress have any interference with intrarenal resistance and hence with mechanisms related to Essential Hypertension (EH) and if Anxiety, Depression, Self efficacy and Illness Perception can account for perceived stress. Obesity, insulin resistance (HOMA), Doppler Renal Resistive Index (RRI) and glomerular filtration rate (GFR) are studied along with Psychological Stress Measure (PSM), Illness Perception Questionnaire (IPQ-R), Generalized Self-Efficacy scale (GSE) and Hospital Anxiety and Depression Scale (HADS) in 119 hypertensive patients referred for stable lasting EH, and 150 normal controls. Lower salt/lower calories Mediterranean diet, physical activity increase and smoking withdrawal counseling were provided. By Odds Ratios, higher risk of EH is associated with greater perceived stress, older age, lower GFR, obesity, greater RRI and insulin resistance. By Multiple Linear Regression the most significant variable that accounts for higher RRI are abdominal obesity and arterial pulse pressure; the only significant independent psychological variable that accounts for abdominal obesity are PSM and identity IPQ subscale. Self-Efficacy anxiety and Illness perception subscales (IPQr), accounts significantly for 62.0% of the variance to PSM, with possible effects on RRI and on the pathophysiological hypertension cascade. Worst identity and treatment control perceptions of EH, and a lower self-efficacy are the main psychological factors accounting for a greater stress. Interventions aimed to reduce perceived stress can be warranted in EH.

  1. Evaluation of Qualitative and Quantitative Traits of Maize (cv. 604 Under Drought Stress and Plant Density

    Directory of Open Access Journals (Sweden)

    Parvaneh Vafa

    2014-05-01

    Full Text Available In order to study the effects of drought stress and plant density on yield and yields Components of maize (cv. 604, an experiment was conducted as a split plot based on randomized complete block design with four replications in Ilam station, Iran during 2007-2008 growing season. The treatment were three levels of irrigation (90, 120 and 150 evaporation (mm from pan (Class A as main plots, four planting densities (90000, 100000, 110000 and 125000 plants ha-1 as sub plot. The results showed that different levels of irrigation on the most of measured traits were significant at 1% probability level. Level of irrigation 90 mm evaporation (mm from pan had a highest a number grain per row, 1000 kernel weight, grain yield and biologic yield other than traits. Between plating density the most of measured traits were significant. The highest grain yield, row per ear, number grain per row, biologic yield and harvest index obtained in 110000 plants ha-1. Interaction effect of irrigation Ч plant density was effect on grain yield. The highest grain yield from 90 mm evaporationЧ110000 plants ha-1 and the lowest grain yield from 150 mm evaporationЧ90000 plants ha-1.

  2. Quantitative Trait Loci from Two Genotypes of Oat (Avena sativa) Conditioning Resistance to Puccinia coronata.

    Science.gov (United States)

    Babiker, Ebrahiem M; Gordon, Tyler C; Jackson, Eric W; Chao, Shiaoman; Harrison, Stephen A; Carson, Martin L; Obert, Don E; Bonman, J Michael

    2015-02-01

    Developing oat cultivars with partial resistance to crown rust would be beneficial and cost-effective for disease management. Two recombinant inbred-line populations were generated by crossing the susceptible cultivar Provena with two partially resistant sources, CDC Boyer and breeding line 94197A1-9-2-2-2-5. A third mapping population was generated by crossing the partially resistant sources to validate the quantitative trait locus (QTL) results. The three populations were evaluated for crown rust severity in the field at Louisiana State University (LSU) in 2009 and 2010 and at the Cereal Disease Laboratory (CDL) in St. Paul, MN, in 2009, 2010, and 2011. An iSelect platform assay containing 5,744 oat single nucleotide polymorphisms was used to genotype the populations. From the 2009 CDL test, linkage analyses revealed two QTLs for partial resistance in the Provena/CDC Boyer population on chromosome 19A. One of the 19A QTLs was also detected in the 2009 LSU test. Another QTL was detected on chromosome 12D in the CDL 2009 test. In the Provena/94197A1-9-2-2-2-5 population, only one QTL was detected, on chromosome 13A, in the CDL 2011 test. The 13A QTL from the Provena/94197A1-9-2-2-2-5 population was validated in the CDC Boyer/94197A1-9-2-2-2-5 population in the CDL 2010 and 2011 tests. Comparative analysis of the significant marker sequences with the rice genome database revealed 15 candidate genes for disease resistance on chromosomes 4 and 6 of rice. These genes could be potential targets for cloning from the two resistant parents.

  3. Mapping Quantitative Trait Loci (QTL for Resistance to Late Blight in Tomato

    Directory of Open Access Journals (Sweden)

    Dilip R. Panthee

    2017-07-01

    Full Text Available Late blight caused by Phytophthora infestans (Montagne, Bary is a devastating disease of tomato worldwide. There are three known major genes, Ph-1, Ph-2, and Ph-3, conferring resistance to late blight. In addition to these three genes, it is also believed that there are additional factors or quantitative trait loci (QTL conferring resistance to late blight. Precise molecular mapping of all those major genes and potential QTL is important in the development of suitable molecular markers and hence, marker-assisted selection (MAS. The objective of the present study was to map the genes and QTL associated with late blight resistance in a tomato population derived from intra-specific crosses. To achieve this objective, a population, derived from the crossings of NC 1CELBR × Fla. 7775, consisting of 250 individuals at F2 and F2-derived families, were evaluated in replicated trials. These were conducted at Mountain Horticultural Crops Reseach & Extension Center (MHCREC at Mills River, NC, and Mountain Research Staion (MRS at Waynesville, NC in 2011, 2014, and 2015. There were two major QTL associated with late blight resistance located on chromosomes 9 and 10 with likelihood of odd (LOD scores of more than 42 and 6, explaining 67% and 14% of the total phenotypic variation, respectively. The major QTLs are probably caused by the Ph-2 and Ph-3 genes. Furthermore, there was a minor QTL on chromosomes 12, which has not been reported before. This minor QTL may be novel and may be worth investigating further. Source of resistance to Ph-2, Ph-3, and this minor QTL traces back to line L3707, or Richter’s Wild Tomato. The combination of major genes and minor QTL may provide a durable resistance to late blight in tomato.

  4. Plant resistance to cold stress: Mechanisms and environmental ...

    Indian Academy of Sciences (India)

    2004-10-28

    Oct 28, 2004 ... Home; Journals; Journal of Biosciences; Volume 29; Issue 4. Plant resistance to cold stress: Mechanisms and environmental signals triggering frost hardening and dehardening ... Keywords. Cold acclimation of plants; environmental signals; frost hardening; photoperiod; phytochrome; Scots pine ...

  5. Plant adaptogens increase lifespan and stress resistance in C. elegans

    NARCIS (Netherlands)

    Wiegant, F.A.C.; Surinova, S.; Ytsma, E.; Langelaar-Makkinje, M.; Wikman, G.; Post, J.A.

    2008-01-01

    Extracts of plant adaptogens such as Eleutherococcus senticosus (or Acanthopanax senticosus) and Rhodiola rosea can increase stress resistance in several model systems. We now show that both extracts also increase the mean lifespan of the nematode C. elegans in a dose-dependent way. In

  6. Neurobiological mechanisms supporting experience-dependent resistance to social stress.

    Science.gov (United States)

    Cooper, M A; Clinard, C T; Morrison, K E

    2015-04-16

    Humans and other animals show a remarkable capacity for resilience following traumatic, stressful events. Resilience is thought to be an active process related to coping with stress, although the cellular and molecular mechanisms that support active coping and stress resistance remain poorly understood. In this review, we focus on the neurobiological mechanisms by which environmental and social experiences promote stress resistance. In male Syrian hamsters, exposure to a brief social defeat stressor leads to increased avoidance of novel opponents, which we call conditioned defeat. Also, hamsters that have achieved dominant social status show reduced conditioned defeat as well as cellular and molecular changes in the neural circuits controlling the conditioned defeat response. We propose that experience-dependent neural plasticity occurs in the prelimbic (PL) cortex, infralimbic (IL) cortex, and ventral medial amygdala (vMeA) during the maintenance of dominance relationships, and that adaptations in these neural circuits support stress resistance in dominant individuals. Overall, behavioral treatments that promote success in competitive interactions may represent valuable interventions for instilling resilience. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Hypersonic Composites Resist Extreme Heat and Stress

    Science.gov (United States)

    2007-01-01

    Through research contracts with NASA, Materials and Electrochemical Research Corporation (MER), of Tucson, Arizona, contributed a number of technologies to record-breaking hypersonic flights. Through this research, MER developed a coating that successfully passed testing to simulate Mach 10 conditions, as well as provide several additional carbon-carbon (C-C) composite components for the flights. MER created all of the leading edges for the X-43A test vehicles at Dryden-considered the most critical parts of this experimental craft. In addition to being very heat resistant, the coating had to be very lightweight and thin, as the aircraft was designed to very precise specifications and could not afford to have a bulky coating. MER patented its carbon-carbon (C-C) composite process and then formed a spinoff company, Frontier Materials Corporation (FMC), also based in Tucson. FMC is using the patent in conjunction with low-cost PAN (polyacrylonitrile)-based fibers to introduce these materials to the commercial markets. The C-C composites are very lightweight and exceptionally strong and stiff, even at very high temperatures. The composites have been used in industrial heating applications, the automotive and aerospace industries, as well as in glass manufacturing and on semiconductors. Applications also include transfer components for glass manufacturing and structural members for carrier support in semiconductor processing.

  8. Reduced resistance to oxidative stress during reproduction as a cost of early-life stress.

    Science.gov (United States)

    Zimmer, Cédric; Spencer, Karen A

    2015-05-01

    Stress exposure during early-life development can have long-term consequences for a variety of biological functions including oxidative stress. The link between early-life stress and oxidative balance is beginning to be explored and previous studies have focused on this link in adult non-breeding or immature individuals. However, as oxidative stress is considered as the main physiological mechanism underlying the trade-off between self-maintenance and investment in reproduction, it is necessary to look at the consequences of early-life stress on oxidative status during reproduction. Here, we investigated the effects of exposure to pre- and/or post-natal stress on oxidative balance during reproduction under benign or stressful environmental conditions in an avian model species, the Japanese quail. We determined total antioxidant status (TAS), total oxidant status (TOS) and resistance to a free-radical attack in individual exposed to pre-natal stress, post-natal stress or both and in control individuals exposed to none of the stressors. TAS levels decreased over time in all females that reproduced under stressful conditions. TOS decreased between the beginning and the end of reproductive period in pre-natal control females. In all females, resistance to a free-radical attack decreased over the reproductive event but this decrease was more pronounced in females from a pre-natal stress development. Our results suggest that pre-natal stress may be associated with a higher cost of reproduction in terms of oxidative stress. These results also confirm that early-life stress can be associated with both benefits and costs depending of the life-history stage or environmental context. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Are adult life history traits in oriental fruit moth affected by a mild pupal heat stress?

    Science.gov (United States)

    Zheng, Jincheng; Cheng, Xiongbin; Hoffmann, Ary A; Zhang, Bo; Ma, Chun-Sen

    2017-10-01

    Thermal stress at one life stage can affect fitness at a later stage in ectotherms with complex life cycles. Most relevant studies have focused on extreme stress levels, but here we also show substantial fitness effects in a moth when pupae are exposed to a relatively mild and sublethal heat stress. We consider the impact of a 35°C heat stress of 2h in three geographically separate populations of the oriental fruit moth (OFM, Grapholita molesta) from northern, middle and southern China. Heat stress negatively affected fecundity but increased adult heat resistance and adult longevity. Fitness effects were mostly consistent across populations but there were also some population differences. In the Shenyang population from northern China, there was a hormetic effect of heat on female longevity not evident in the other populations. Adults from all populations had higher LT 50 s due to heat stress after pupal exposure to the sublethal stress. These results highlight that the pupal stage is a particularly sensitive window for development and they have implications for seasonal adaptation in uncertain environments as well as changes in pest dynamics under climate warming. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Antimicrobial resistance and virulence traits in Enterococcus strains isolated from dogs and cats.

    Science.gov (United States)

    Iseppi, Ramona; Messi, Patrizia; Anacarso, Imacolata; Bondi, Moreno; Sabia, Carla; Condò, Carla; de Niederhausern, Simona

    2015-07-01

    We investigated presence and prevalence of antibiotic-resistances and other biological characters in enterococci isolated from faeces of healthy dogs and cats because these microorganisms represent important human and veterinary pathogens/opportunists, and a significant burden for healthcare systems. In all samples (n=115) we detected enterococci, with a predominance of Enterococcus faecium (42; 36.5%) and Enterococcus faecalis (36; 31.3%) species, endowed with virulence traits and multidrug-resistance. The two predominant resistance patterns (erythromycin, tetracycline) were examined by polymerase chain reaction for tet and erm genes. Only tetM for tetracycline, and ermA and ermB for erythromycin were detected. PCR for gelatinase gene (gelE) was positive in 62.6% of isolates, but only 26.1% produce gelatinase suggesting the existence of silent genes. efaAfs and efaAfm genes were found in E. faecalis and E. faecium respectively. 89.6% of isolates produced bacteriocin-like substances with a prevailing action against Listeria genus and, among these, 33.9% were positive for the bacteriocin structural genes entA, entL50 or entP. According to our study, pet animals can be considered a reservoir of potentially pathogenic enterococci and we cannot exclude that those microorganisms may be responsible for opportunistic infections in high-risk pet owners.

  11. Evaluation of Water Stress on Yield, Its Components and Some Physiological Traits at Different Growth Stages in Grain Sorghum Genotypes

    Directory of Open Access Journals (Sweden)

    Ali AZARINASRABAD

    2016-06-01

    Full Text Available Investigation on yield improvement and development under drought condition using breeding techniques is difficult, due to the association with low heritability of specific traits. Even more, investigation of physiological indicators (stomatal conductance, chlorophyll index, relative water content, chlorophyll fluorescence, canopy temperature, radiation use efficiency, stay-green etc. is of interest as they are more accessible, with a low cost, therefore these indicators of physiological traits can be used as good criteria in selecting valuable species. In order to evaluate the effects of water stress on grain yield, its components and some physiological traits of grain sorghum genotypes (Sorghum bicolor L., a field experiment using split plot design with three replications was carried. The main plots included three water stress treatments: normal irrigation as control, halting irrigation at the stage of terminal leaf emergence and halting irrigation at the stage of 50% flowering. The sub-plots included 10 genotypes of sorghum (‘KGS29’, ‘MGS2’, ‘Sepideh’, ‘KGFS27’, ‘MGS5’, ‘KGFS5’, ‘KGFS17’, ‘KGFS13’ and ‘KGFS30’. Results showed that water stress significantly decreased grain yield and its components (1,000 seed weight, number of seed per panicle and had various effects on physiological traits. The water stress increased canopy temperature and radiation use efficiency, while stomatal conductance, chlorophyll index (SPAD and stay-green of genotypes were decreased; the maximum efficiency of photosystem II of photosynthesis remained unchanged between the treatments. Genotypes turned out to have significantly different responses to the drought treatments for all the studied traits, indicating the existence of a high variability among them. In general, physiological traits could be used as good indicators in water stress investigations and might provide comprehensive information as compared with morphological traits.

  12. Impedance of the Grape Berry Cuticle as a Novel Phenotypic Trait to Estimate Resistance to Botrytis Cinerea

    Directory of Open Access Journals (Sweden)

    Katja Herzog

    2015-05-01

    Full Text Available Warm and moist weather conditions during berry ripening provoke Botrytis cinerea (B. cinerea causing notable bunch rot on susceptible grapevines with the effect of reduced yield and wine quality. Resistance donors of genetic loci to increase B. cinerea resistance are widely unknown. Promising traits of resistance are represented by physical features like the thickness and permeability of the grape berry cuticle. Sensor-based phenotyping methods or genetic markers are rare for such traits. In the present study, the simple-to-handle I-sensor was developed. The sensor enables the fast and reliable measurement of electrical impedance of the grape berry cuticles and its epicuticular waxes (CW. Statistical experiments revealed highly significant correlations between relative impedance of CW and the resistance of grapevines to B. cinerea. Thus, the relative impedance Zrel of CW was identified as the most important phenotypic factor with regard to the prediction of grapevine resistance to B. cinerea. An ordinal logistic regression analysis revealed a R2McFadden of 0.37 and confirmed the application of Zrel of CW for the prediction of bunch infection and in this way as novel phenotyping trait. Applying the I-sensor, a preliminary QTL region was identified indicating that the novel phenotypic trait is as well a valuable tool for genetic analyses.

  13. Stem hydraulic traits and leaf water-stress tolerance are co-ordinated with the leaf phenology of angiosperm trees in an Asian tropical dry karst forest.

    Science.gov (United States)

    Fu, Pei-Li; Jiang, Yan-Juan; Wang, Ai-Ying; Brodribb, Tim J; Zhang, Jiao-Lin; Zhu, Shi-Dan; Cao, Kun-Fang

    2012-07-01

    The co-occurring of evergreen and deciduous angiosperm trees in Asian tropical dry forests on karst substrates suggests the existence of different water-use strategies among species. In this study it is hypothesized that the co-occurring evergreen and deciduous trees differ in stem hydraulic traits and leaf water relationships, and there will be correlated evolution in drought tolerance between leaves and stems. A comparison was made of stem hydraulic conductivity, vulnerability curves, wood anatomy, leaf life span, leaf pressure-volume characteristics and photosynthetic capacity of six evergreen and six deciduous tree species co-occurring in a tropical dry karst forest in south-west China. The correlated evolution of leaf and stem traits was examined using both traditional and phylogenetic independent contrasts correlations. It was found that the deciduous trees had higher stem hydraulic efficiency, greater hydraulically weighted vessel diameter (D(h)) and higher mass-based photosynthetic rate (A(m)); while the evergreen species had greater xylem-cavitation resistance, lower leaf turgor-loss point water potential (π(0)) and higher bulk modulus of elasticity. There were evolutionary correlations between leaf life span and stem hydraulic efficiency, A(m), and dry season π(0). Xylem-cavitation resistance was evolutionarily correlated with stem hydraulic efficiency, D(h), as well as dry season π(0). Both wood density and leaf density were closely correlated with leaf water-stress tolerance and A(m). The results reveal the clear distinctions in stem hydraulic traits and leaf water-stress tolerance between the co-occurring evergreen and deciduous angiosperm trees in an Asian dry karst forest. A novel pattern was demonstrated linking leaf longevity with stem hydraulic efficiency and leaf water-stress tolerance. The results show the correlated evolution in drought tolerance between stems and leaves.

  14. The etiology of oxidative stress in insulin resistance

    Directory of Open Access Journals (Sweden)

    Samantha Hurrle

    2017-10-01

    Full Text Available Insulin resistance is a prevalent syndrome in developed as well as developing countries. It is the predisposing factor for type 2 diabetes mellitus, the most common end stage development of metabolic syndrome in the United States. Previously, studies investigating type 2 diabetes have focused on beta cell dysfunction in the pancreas and insulin resistance, and developing ways to correct these dysfunctions. However, in recent years, there has been a profound interest in the role that oxidative stress in the peripheral tissues plays to induce insulin resistance. The objective of this review is to focus on the mechanism of oxidative species generation and its direct correlation to insulin resistance, to discuss the role of obesity in the pathophysiology of this phenomenon, and to explore the potential of antioxidants as treatments for metabolic dysfunction.

  15. Genetic dissection of milk yield traits and mastitis resistance QTL on chromosome 20 in dairy cattle

    DEFF Research Database (Denmark)

    Kadri, Naveen Kumar; Guldbrandtsen, Bernt; Lund, Mogens Sandø

    2015-01-01

    Intense selection to increase milk yield has had negative consequences for mastitis incidence in dairy cattle. Due to low heritability of mastitis resistance and an unfavorable genetic correlation with milk yield, a reduction in mastitis through traditional breeding has been difficult to achieve........ Here, we examined quantitative trait loci (QTL) that segregate for clinical mastitis (CM) and milk yield (MY) on Bos taurus autosome 20 (BTA20) to determine whether both traits are affected by a single polymorphism (pleiotropy) or by multiple closely linked polymorphisms. In the latter...... nucleotide polymorphisms (SNP) on BTA20. Data were combined, phased, and clustered into haplotype states, followed by within- and across-breed haplotype-based association analyses using a linear mixed model. Association signals for both CM and MY peaked in the 26 to 40 Mb region on BTA20 in HOL. Single......, there was indication on differences in the causal factor(s) across breeds. A previously reported F279Y mutation (rs385640152) within the growth hormone receptor (GHR) gene showed strong association with milk, fat, protein yields. In HOL, the highest peaks for milk yield and susceptibility to mastitis were separated...

  16. Salivary Testosterone Levels Under Psychological Stress and Its Relationship with Rumination and Five Personality Traits in Medical Students

    Science.gov (United States)

    Afrisham, Reza; Sadegh-Nejadi, Sahar; SoliemaniFar, Omid; Kooti, Wesam; Ashtary-Larky, Damoon; Alamiri, Fatima; Najjar-Asl, Sedigheh; Khaneh-Keshi, Ali

    2016-01-01

    Objective The purpose of this study was to evaluate the salivary testosterone levels under psychological stress and its relationship with rumination and five personality traits in medical students. Methods A total of 58 medical students, who wanted to participate in the final exam, were selected by simple random sampling. Two months before the exam, in the basal conditions, the NEO Inventory short form, and the Emotional Control Questionnaire (ECQ) were completed. Saliva samples were taken from students in both the basal conditions and under exam stress. Salivary testosterone was measured by ELISA. Data was analyzed using multivariate analysis of variance with repeated measures, paired samples t-test, Pearson correlation and stepwise regression analysis. Results Salivary testosterone level of men showed a significant increase under exam stress (pstress. Conclusion Salivary testosterone reactivity to stress can be determined by sexual differences, personality traits, and emotional control variables which may decrease or increase stress effects on biological responses, especially the salivary testosterone. PMID:27909455

  17. Salivary Testosterone Levels Under Psychological Stress and Its Relationship with Rumination and Five Personality Traits in Medical Students.

    Science.gov (United States)

    Afrisham, Reza; Sadegh-Nejadi, Sahar; SoliemaniFar, Omid; Kooti, Wesam; Ashtary-Larky, Damoon; Alamiri, Fatima; Aberomand, Mohammad; Najjar-Asl, Sedigheh; Khaneh-Keshi, Ali

    2016-11-01

    The purpose of this study was to evaluate the salivary testosterone levels under psychological stress and its relationship with rumination and five personality traits in medical students. A total of 58 medical students, who wanted to participate in the final exam, were selected by simple random sampling. Two months before the exam, in the basal conditions, the NEO Inventory short form, and the Emotional Control Questionnaire (ECQ) were completed. Saliva samples were taken from students in both the basal conditions and under exam stress. Salivary testosterone was measured by ELISA. Data was analyzed using multivariate analysis of variance with repeated measures, paired samples t-test, Pearson correlation and stepwise regression analysis. Salivary testosterone level of men showed a significant increase under exam stress (pstress. Salivary testosterone reactivity to stress can be determined by sexual differences, personality traits, and emotional control variables which may decrease or increase stress effects on biological responses, especially the salivary testosterone.

  18. Interaction between prenatal maternal stress and autonomic arousal in predicting conduct problems and psychopathic traits in children.

    Science.gov (United States)

    Gao, Yu; Huang, Yonglin; Li, Xiaobo

    2017-03-01

    Evidence has suggested that neurobiological deficits combine with psychosocial risk factors to impact on the development of antisocial behavior. The current study concentrated on the interplay of prenatal maternal stress and autonomic arousal in predicting antisocial behavior and psychopathic traits. Prenatal maternal stress was assessed by caregiver's retrospective report, and resting heart rate and respiratory sinus arrhythmia (RSA) were measured in 295 8- to 10-year-old children. Child and caregiver also reported on child's antisocial behavior and psychopathic traits. Higher prenatal maternal stress was associated with higher caregiver-reported antisocial and psychopathy scores, even after the concurrent measure of social adversity was controlled for. As expected, low heart rate and high RSA were associated with high antisocial and psychopathic traits. More importantly, significant interaction effects were found; prenatal stress was positively associated with multiple dimensions of psychopathic traits only on the conditions of low arousal (e.g., low heart rate or high RSA). Findings provide further support for a biosocial perspective of antisocial and psychopathic traits, and illustrate the importance of integrating biological with psychosocial measures to fully understand the etiology of behavioral problems.

  19. Using plant traits to evaluate the resistance and resilience of ecosystem service provision

    Science.gov (United States)

    Kohler, Marina; Devaux, Caroline; Fontana, Veronika; Grigulis, Karl; Lavorel, Sandra; Leitinger, Georg; Schirpke, Uta; Tasser, Erich; Tappeiner, Ulrike

    2015-04-01

    Mountain grassland ecosystems are a hotspot of biodiversity and deliver a multiplicity of ecosystem services. Due to a long history of well adapted agricultural use and specific environmental conditions (e.g. slope, altitude, or climate), various types of grassland ecosystems have developed. Each of them shows specific attributes in forms of plant communities and abiotic characteristics, which lead to particular ranges of ecosystem service provision. However, ongoing climate and societal changes thread plant community composition and may lead to changes in plant traits, and therefore, the provision of ecosystem services. Currently it is not clear how vulnerable these ecosystems are to disturbances, or whether they have developed a high resilience over time. Thus, it is essential to know the ranges of resistance and resilience of an ecosystem service. We, therefore, developed a static approach based on community weighted mean plant traits and abiotic parameters to measure the boundaries of resistance and resilience of each ecosystem service separately. By calculating actual minimum and maximum amounts of ecosystem services, we define the range of resistance of an ecosystem service. We then calculate the potential amount of an ecosystem services (via simulated plant communities) by assuming that no species is lost or added to the system. By comparing actual and potential values, we can estimate whether an ecosystem service is in danger to lose its resilience. We selected different ecosystem services related to mountain grassland ecosystems, e.g. carbon storage, forage quality, forage quantity, and soil fertility. We analysed each ecosystem service for different grassland management types, covering meadows and pastures of very low land-use intensity through to grasslands of high land-use intensity. Results indicate that certain ecosystem services have a higher resilience than others (e.g. carbon storage) for all management types. The ecosystem may provide steady

  20. Genetic Analysis for Some of Morphological Traits in Bread Wheat under Drought Stress Condition Using Generations Mean Analysis

    Directory of Open Access Journals (Sweden)

    Jamileh Abedi

    2015-06-01

    Full Text Available Perception of genes action controlling of quantitative traits is very important in genetic breeding methods the plant populations. to study and estimate the parameters of genetic and appointment the best genetically model for justification the genetic changing some of traits the bread wheat under drought stress condition, parents (P1 & P2 and F3, F4, F5 generations together the four control cultivars (Kharchia, Gaspard, Moghan and Mahuti were evaluated by generation mean analysis using a agoment design including six blocks. Generation mean analysis was performed for all traits with Mather and Jinks model using joint scaling test. Three parameter model [m d h] provided the best fit for all traits expect harvest index, main spike grain weight, number of grain per plant, Total spike weight of plant with significant at 5% and 1% levels . Though additive and dominance effect both had interfered in controlling often the traits but with attention to difference effects and variety component was determined that dominance is more impressive than additive effect for traits of number of tiller, main spike weight, grain yield and grain number of main spike. Therefore will benefit using of these traits in the collection and to improve these traits hybridization would be much efficient than the selection strategies. In this study additive Ч additive epistasis effect only observed for traits of Total spike weight of plant, number of grain per plant, main spike grain weight and harvest index and other traits hadn’t any epistasis effect that it was demonstration lack of existence the genes reciprocal effect in the inheritance studied traits. Therefore we can suggest that the selection strategies perform in terminal generations and additive Ч additive epistasis effect would be confirmed in selection under self-pollination condition.

  1. Discovery of quantitative trait loci for resistance to parasitic nematode infection in sheep: I. Analysis of outcross pedigrees

    Directory of Open Access Journals (Sweden)

    Greer Gordon J

    2006-07-01

    Full Text Available Abstract Background Currently most pastoral farmers rely on anthelmintic drenches to control gastrointestinal parasitic nematodes in sheep. Resistance to anthelmintics is rapidly increasing in nematode populations such that on some farms none of the drench families are now completely effective. It is well established that host resistance to nematode infection is a moderately heritable trait. This study was undertaken to identify regions of the genome, quantitative trait loci (QTL that contain genes affecting resistance to parasitic nematodes. Results Rams obtained from crossing nematode parasite resistant and susceptible selection lines were used to derive five large half-sib families comprising between 348 and 101 offspring per sire. Total offspring comprised 940 lambs. Extensive measurements for a range of parasite burden and immune function traits in all offspring allowed each lamb in each pedigree to be ranked for relative resistance to nematode parasites. Initially the 22 most resistant and 22 most susceptible progeny from each pedigree were used in a genome scan that used 203 microsatellite markers spread across all sheep autosomes. This study identified 9 chromosomes with regions showing sufficient linkage to warrant the genotyping of all offspring. After genotyping all offspring with markers covering Chromosomes 1, 3, 4, 5, 8, 12, 13, 22 and 23, the telomeric end of chromosome 8 was identified as having a significant QTL for parasite resistance as measured by the number of Trichostrongylus spp. adults in the abomasum and small intestine at the end of the second parasite challenge. Two further QTL for associated immune function traits of total serum IgE and T. colubiformis specific serum IgG, at the end of the second parasite challenge, were identified on chromosome 23. Conclusion Despite parasite resistance being a moderately heritable trait, this large study was able to identify only a single significant QTL associated with it. The QTL

  2. Determining resistance to mastitis in a bovine subject comprises detecting the presence or absence of a genetic marker that is linked to a trait indicative of mastitis resistance

    DEFF Research Database (Denmark)

    2007-01-01

    The invention relates to a method for determining mastitis resistance in bovine subjects, wherein mastitis resistance comprise resistance to both sub-clinical and clinical mastitis. In particular, the method of the invention involves identification of genetic markers and/or Quantitative Trait Locus...... (QTL) for the determination of mastitis resistance in a bovine subject. The determination of mastitis resistance involves resolution of the specific microsatellite status. Furthermore, the invention relates to a diagnostic kit for detection of genetic marker(s) associated with mastitis resistance....... The method and kit of the present invention can be applied for selection of bovine subjects for breeding purposes. Thus, the invention provides a method of genetically selecting bovine subjects with mastitis resistance, thereby yielding cows less prone to mastitis...

  3. Phenotypic Stability of Zea mays Grain Yield and Its Attributing Traits under Drought Stress

    Directory of Open Access Journals (Sweden)

    Fawad Ali

    2017-08-01

    Full Text Available Phenotypic stability under stress environment facilitate the fitness of genotype and opens new horizons to explore the cryptic genetic variation. Variation in tolerance to drought stress, a major grain yield constraint to global maize production, was identified, at the phenotypic and genotypic level. Here we found a prominent hybrid H9 that showed fitness over four growing seasons for grain yield under water stress conditions. Genotypic and phenotypic correlation of yield attributing traits over four seasons demonstrated that cobs per plant, 100 seed weight, number of grains rows per cob, total dry matter, cob diameter had positive association (r2 = 0.3–0.9 to grain yield. The perturbation was found for chlorophyll content as it showed moderate to strong association (P < 0.01 over four seasons, might be due to environment or genotype dependent. Highest heritability (95% and genetic advance (79% for grain yield was found in H9 over four consecutive crop growing seasons. Combined analysis over four seasons showed that studied variables together explained 85% of total variation in dependent structure (grain yield obtained by Principal component analysis. This significant finding is the best example of phenotypic stability of grain yield in H9 and made it best fitted for grain yield under drought stress scenario. Detailed genetic analysis of H9 will help us to identify significant loci and alleles that made H9 the best fitted and it could serve as a potential source to generate novel transgressive levels of tolerance for drought stress in arid/semiarid regions.

  4. Immunological traits have the potential to improve selection of pigs for resistance to clinical and subclinical disease

    DEFF Research Database (Denmark)

    Henryon, M.; Heegaard, Peter M. H.; Nielsen, Jens

    2006-01-01

    , potentially useful as criteria to improve selection of pigs for resistance to clinical and subclinical disease. We tested this premise by assessing 4204 male pigs from the Duroc, Landrace, and Yorkshire breeds for total and differential numbers of leukocytes and serum concentrations of IgG and haptoglobin...... models to the expression levels of SLA I and II. We detected additive genetic variation for each group of traits. Total and differential numbers of leukocytes were moderately heritable (h(2) = 0.22 to 0.30), expression levels of SLA I and II were moderate-to-highly heritable (h(2) = 0.46 to 1.23), while...... serum concentrations of IgG and haptoglobin were lowly heritable (h(2) = 0.14 to 0.16). The additive genetic variation shown for the immunological traits is encouraging for pig breeders. It indicates that these traits are potentially useful as criteria to improve selection of pigs for resistance...

  5. Response of Wheat Physiological and Agronomic Traits to Water Stress and Zeolite Application

    Directory of Open Access Journals (Sweden)

    M Mirzakhani

    2015-07-01

    Full Text Available With increasing water deficit in agricultural production, quantity and quality of these products will be affected. In order to evaluate the response of wheat physiological and agronomic characteristics to water stress and zeolite application, this study was carried out in field of Arak Payam Noor University in 2009. A split-plot arrangement of treatments in a randomized complete block design with three replications was used. Water stress (I0= Control irrigation, I1= Irrigation about 85% plant requirement water, I2= Irrigation about 70% of plant requirement water, I3= Irrigation about 55% of plant requirement water, were assigned in the main plots and different levels of zeolite application (Z0= without zeolite application, Z1= 3 ton ha-1, Z2= 6 ton ha-1, Z3= 9 ton ha-1 in sub plots. Each sub plot consisted of 4 rows, 5 m long with 50 cm between rows space and 5 cm between plants on the rows. Results indicated that un-stress irrigation (control irrigation with average spike biological yield (36.51 g per 10 plant and zeolite application (9 ton ha-1 with average (34.02 g per 10 plant were significantly superior to the other treatments. The maximum and minimum of grain yield obtained of treatments (control irrigation + 9 ton ha-1 of zeolite and (irrigation about 55% of plant requirement water + 3 ton ha-1 of zeolite, respectively. Zeolite application was positive affected on almost of agronomic and physiologic traits in wheat.

  6. Gene-based Association Approach Identify Genes Across Stress Traits in Fruit Flies

    DEFF Research Database (Denmark)

    Rohde, Palle Duun; Edwards, Stefan McKinnon; Sarup, Pernille Merete

    Identification of genes explaining variation in quantitative traits or genetic risk factors of human diseases requires both good phenotypic- and genotypic data, but also efficient statistical methods. Genome-wide association studies may reveal association between phenotypic variation and variation...... at nucleotide level, thus potentially identify genetic variants. However, testing million of polymorphic nucleotide positions requires conservative correction for multiple testing which lowers the probability of finding genes with small to moderate effects. To alleviate this, we apply a gene based association...... approach grouping variants accordingly to gene position, thus lowering the number of statistical tests performed and increasing the probability of identifying genes with small to moderate effects. Using this approach we identify numerous genes associated with different types of stresses in Drosophila...

  7. Research on the Effects of Water Stress on Growth Traits and Water Use Efficiency of Winter Wheat

    OpenAIRE

    Sun Shuhong; Liu Ling; Yang Shusheng

    2015-01-01

    This research about the effects of water stress at different growth stages on the crop growth traits has a practical significance in guiding water-saving irrigation. The box test method is adopted to test the water stress of winter wheat at different stages, observe the plant height, leaf area and yield, and analyze the water use efficiency under the condition of water stress. The results show that the water stress in each growth period will play an inhibiting role in the plant height and lea...

  8. Oxidized LDL Is Associated With Metabolic Syndrome Traits Independently of Central Obesity and Insulin Resistance.

    Science.gov (United States)

    Hurtado-Roca, Yamilee; Bueno, Hector; Fernandez-Ortiz, Antonio; Ordovas, Jose Maria; Ibañez, Borja; Fuster, Valentin; Rodriguez-Artalejo, Fernando; Laclaustra, Martin

    2017-02-01

    This study assesses whether oxidative stress, using oxidized LDL (ox-LDL) as a proxy, is associated with metabolic syndrome (MS), whether ox-LDL mediates the association between central obesity and MS, and whether insulin resistance mediates the association between ox-LDL and MS. We examined baseline data from 3,987 subjects without diabetes in the Progression of Early Subclinical Atherosclerosis (PESA) Study. For the second, third, and fourth ox-LDL quartiles versus the first, the odds ratios (95% CI) for MS were 0.84 (0.52, 1.36), 1.47 (0.95, 2.32), and 2.57 (1.66, 4.04) (P insulin resistance (HOMA-IR). Results showing the same trend were found for all MS components except glucose concentration. Ox-LDL mediated 13.9% of the association of waist circumference with triglycerides and only 1-3% of the association with HDL-cholesterol, blood pressure, and insulin concentration. HOMA-IR did not mediate the association between ox-LDL and MS components. This study found higher ox-LDL concentrations were associated with MS and its components independently of central obesity and insulin resistance. Ox-LDL may reflect core mechanisms through which MS components develop and progress in parallel with insulin resistance and could be a clinically relevant predictor of MS development. © 2017 by the American Diabetes Association.

  9. Yield and yield traits of durum wheat (Triticum durum desf. and bread wheat (Triticum aestivum L. genotypes under drought stress

    Directory of Open Access Journals (Sweden)

    Allahverdiyev Tofig

    2016-01-01

    Full Text Available Field experiment was conducted to study the effect of water stress on yield and yield traits of durum wheat and bread wheat genotypes. Water stress caused significant reduction in plant height (PH, peduncle length (PL, spike number/m2(SN, spike length (SL, spike width (SW, spikelets number/spike (SNS, spike mass (SM, grain number/spike (GNS, grain mass/spike (GMS, biological yield (BY, thousand kernel mass (TKM, grain yield (GY and harvest index (HI. Wheat traits such as SN, SM, BY, TKM, GY were more vulnerable to drought stress. Positive significant correlation of GY with SN, BY and HI under rain-fed condition was found. Genotypes of durum wheat were more sensitive to drought than that bread wheat genotypes. The significant and positive correlation of GY with Stress Tolerance Index (STI, Mean Productivity (MP and Geometric Mean Productivity (GMP indicated that these indices were more effective in identifying high yielding, drought tolerance genotypes.

  10. A Comparison Between Job Stress and Insulin Resistance Among the Hospital Medical Staff

    OpenAIRE

    Zareian; Ghasemi; Abtahi,; Behzadi

    2016-01-01

    Background One of the important risk factors for insulin resistance is stress and a major source of stress is job stress. Objectives The current study aimed to determine the relationship between job stress score and insulin resistance among medical staff of the Imam Reza hospital, Tehran, Iran Methods The current descriptive cross-sectional study was performed on 97 medical staff o...

  11. Oxidative stress, insulin resistance, dyslipidemia and type 2 diabetes mellitus

    Science.gov (United States)

    Tangvarasittichai, Surapon

    2015-01-01

    Oxidative stress is increased in metabolic syndrome and type 2 diabetes mellitus (T2DM) and this appears to underlie the development of cardiovascular disease, T2DM and diabetic complications. Increased oxidative stress appears to be a deleterious factor leading to insulin resistance, dyslipidemia, β-cell dysfunction, impaired glucose tolerance and ultimately leading to T2DM. Chronic oxidative stress, hyperglycemia and dyslipidemia are particularly dangerous for β-cells from lowest levels of antioxidant, have high oxidative energy requirements, decrease the gene expression of key β-cell genes and induce cell death. If β-cell functioning is impaired, it results in an under production of insulin, impairs glucose stimulated insulin secretion, fasting hyperglycemia and eventually the development of T2DM. PMID:25897356

  12. Leaf mechanical resistance in plant trait databases: comparing the results of two common measurement methods.

    Science.gov (United States)

    Enrico, Lucas; Díaz, Sandra; Westoby, Mark; Rice, Barbara L

    2016-01-01

    The influence of leaf mechanical properties on local ecosystem processes, such as trophic transfer, decomposition and nutrient cycling, has resulted in a growing interest in including leaf mechanical resistance in large-scale databases of plant functional traits. 'Specific work to shear' and 'force to tear' are two properties commonly used to describe mechanical resistance (toughness or strength) of leaves. Two methodologies have been widely used to measure them across large datasets. This study aimed to assess correlations and standardization between the two methods, as measured by two widely used apparatuses, in order to inter-convert existing data in those global datasets. Specific work to shear (W(SS)) and force to tear (FT) were measured in leaves of 72 species from south-eastern Australia. The measurements were made including and excluding midribs. Relationships between the variables were tested by Spearman correlations and ordinary least square regressions. A positive and significant correlation was found between the methods, but coefficients varied according to the inclusion or exclusion of the midrib in the measurements. Equations for prediction varied according to leaf venation pattern. A positive and significant (r = 0·90, P leaf mechanical resistance data obtained with both methodologies could be pooled together into a single coarser variable, using the equations provided in this paper. However, more detailed datasets of FT cannot be safely filled in with estimations based on W(SS), or vice versa. In addition, W(SS) values of green leaves can be predicted with good accuracy from W(SS) of rehydrated leaves of the same species. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Selection on Crop-Derived Traits and QTL in Sunflower (Helianthus annuus) Crop-Wild Hybrids under Water Stress

    OpenAIRE

    Owart, Birkin R.; Jonathan Corbi; John M Burke; Jennifer M Dechaine

    2014-01-01

    Locally relevant conditions, such as water stress in irrigated agricultural regions, should be considered when assessing the risk of crop allele introgression into wild populations following hybridization. Although research in cultivars has suggested that domestication traits may reduce fecundity under water stress as compared to wild-like phenotypes, this has not been investigated in crop-wild hybrids. In this study, we examine phenotypic selection acting on, as well as the genetic architect...

  14. The relationship between posttraumatic stress disorder, psychiatric comorbidity, and personality traits among patients with chronic idiopathic urticaria.

    Science.gov (United States)

    Chung, Man Cheung; Symons, Christine; Gilliam, Jane; Kaminski, Edward R

    2010-01-01

    Several studies have highlighted the link between posttraumatic stress disorder (PTSD) and physical illnesses. No empirical studies, however, have investigated the relationship between PTSD and chronic idiopathic urticaria (CIU). The role of personality traits in this relationship was also unknown. This study aimed to investigate (1) the extent to which patients with CIU fulfilled the PTSD diagnosis resulting from past traumas and (2) whether they developed psychiatric comorbidity, and (3) the relationship between CIU patients' personality traits, PTSD diagnosis, severity of CIU, and psychiatric comorbidity. One hundred patients with CIU and 60 patients with allergy (control) participated in the study. Patients' CIU severity was assessed. Both groups completed the Posttraumatic Stress Diagnostic Scale, the General Health Questionnaire-28, the Social Readjustment Rating Scale, the Perceived Stress Scale, and the NEO-Five Factor Inventory. Thirty-four percent of patients with CIU and 18% of allergy patients met the diagnostic criteria for PTSD. Patients with CIU were 1.89 times more likely to have a current diagnosis of PTSD than the control group. Controlling for life event stress and perceived stress, significant differences were found between groups (CIU PTSD, CIU no PTSD, allergy PTSD, allergy no PTSD) in somatic problems, anxiety, and social dysfunction. Controlling for life event stress and perceived stress, regression analyses showed no significant associations between personality traits, PTSD diagnosis, and the severity of CIU. Posttraumatic stress disorder diagnosis and neuroticism were, however, associated with psychiatric comorbidity. Patients with CIU have been shown to have concurrent PTSD resulting from past traumas and developed psychiatric comorbidity. Chronic idiopathic urticaria patients' comorbidity was related to the patients' PTSD diagnosis and their neurotic personality trait.

  15. Identification of Loci Associated with Drought Resistance Traits in Heterozygous Autotetraploid Alfalfa (Medicago sativa L.) Using Genome-Wide Association Studies with Genotyping by Sequencing.

    Science.gov (United States)

    Zhang, Tiejun; Yu, Long-Xi; Zheng, Ping; Li, Yajun; Rivera, Martha; Main, Dorrie; Greene, Stephanie L

    2015-01-01

    Drought resistance is an important breeding target for enhancing alfalfa productivity in arid and semi-arid regions. Identification of genes involved in drought tolerance will facilitate breeding for improving drought resistance and water use efficiency in alfalfa. Our objective was to use a diversity panel of alfalfa accessions comprised of 198 cultivars and landraces to identify genes involved in drought tolerance. The panel was selected from the USDA-ARS National Plant Germplasm System alfalfa collection and genotyped using genotyping by sequencing. A greenhouse procedure was used for phenotyping two important traits associated with drought tolerance: drought resistance index (DRI) and relative leaf water content (RWC). Marker-trait association identified nineteen and fifteen loci associated with DRI and RWC, respectively. Alignments of target sequences flanking to the resistance loci against the reference genome of M. truncatula revealed multiple chromosomal locations. Markers associated with DRI are located on all chromosomes while markers associated with RWC are located on chromosomes 1, 2, 3, 4, 5, 6 and 7. Co-localizations of significant markers between DRI and RWC were found on chromosomes 3, 5 and 7. Most loci associated with DRI in this work overlap with the reported QTLs associated with biomass under drought in alfalfa. Additional significant markers were targeted to several contigs with unknown chromosomal locations. BLAST search using their flanking sequences revealed homology to several annotated genes with functions in stress tolerance. With further validation, these markers may be used for marker-assisted breeding new alfalfa varieties with drought resistance and enhanced water use efficiency.

  16. Consistent boldness behaviour in early emerging fry of domesticated Atlantic salmon (Salmo salar): Decoupling of behavioural and physiological traits of the proactive stress coping style

    DEFF Research Database (Denmark)

    Vaz-Serrano, J.; Ruiz-Gomez, M. L.; Gjøen, H. M.

    2011-01-01

    hunger, in the present study. This observation was repeated five months after emergence, demonstrating behavioural consistency over time in this trait. However, in other traits of proactive and reactive stress coping styles, such as social status, resting metabolism or post stress cortisol concentrations...

  17. Analysis of the impact of biomechanical traits of European black Poplar on riverbank flow resistance

    Science.gov (United States)

    Battista Chirico, Giovanni; Saulino, Luigi; Pasquino, Vittorio; Villani, Paolo; Rita, Angelo; Todaro, Luigi; Saracino, Antonio

    2016-04-01

    Predicting the effects of riparian plants on river flow dynamics is fundamental for an appropriate river management. Riparian woody vegetation enhances bank cohesion and provides ecosystem services by mitigating nutrient and sediment loads to the river flow and enhancing biodiversity. However riparian trees also contribute to river flow resistance and thus can have a significant impact on flow dynamics during flood events. The flow-plant interaction mainly depends on plant morphological characters (e.g. diameter, height, canopy size, foliage density) and biomechanical properties, such as its flexural rigidity. This study aims at testing the hypothesis that the hydrodynamic behaviour of the European black Poplar (∖textit{Populus nigra} L.), a common woody riparian plant, is influenced by specific biomechanical traits developed as result of its adaptation to different river ecosystems. We examine the morphological and biomechanical properties of living stems of black Poplar sampled in two different riverine environments in Southern Italy located only a few kilometres apart. The two sample sets of living stems exhibit similar morphological traits but significantly different Young module of elasticity. We compared the drag forces that the flow would exert on these two different sets of plants for a wide range of flow velocities, by employing a numerical model that accounts for the bending behaviour of the woody plant due to the hydrodynamic load, under the hypothesis of complete submergence. A Monte Carlo approach was applied in order to account for the stochastic variability of the morphological and mechanical parameters affecting plant biomechanical behaviour. We identified a threshold value of the plant diameter, above which the two sets of European black Poplars are subjected to drag forces that differ by more than 25{∖%} on average, for flow velocities larger than 1 m/s.

  18. The relationship between recent stressful life events, personality traits, perceived family functioning and internet addiction among college students.

    Science.gov (United States)

    Yan, Wansen; Li, Yonghui; Sui, Nan

    2014-02-01

    Internet addiction (IA) is an emerging social and mental health issue among youths. Analysis of risk factors, as well as their interactions, is crucial for understanding the development of IA. This study investigated the relationship between recent stressful life events, personality traits, perceived family functioning and IA in 892 college students. Subjects were classified into categories (non-addicted, mild IA or severe IA) using the Chen Internet Addiction Scale. Stressful life events, personality traits and family functioning were assessed using the Adolescent Self-Rating Life Events Checklist, the Eysenck Personality Questionnaire, and the Family Adaptability and Cohesion Scale, respectively. The results indicated that compared with non-addicted subjects, subjects with severe IA (9.98%) had lower family functioning, lower extraversion, higher neuroticism and psychoticism, and more stressful life events, and subjects with mild IA (11.21%) had higher neuroticism and more health and adaptation problems. Neuroticism and health and adaptation problems were potential predictors of IA. An interaction effect between psychoticism and total life stress on IA was also found. These findings highlight the role of personality traits and life stress and their interactions in college students' IA. Further research should explore the mechanisms underlying the interaction effect of psychoticism with life stress on IA. Copyright © 2013 John Wiley & Sons, Ltd.

  19. How integrated are behavioral and endocrine stress response traits? A repeated measures approach to testing the stress-coping style model.

    Science.gov (United States)

    Boulton, Kay; Couto, Elsa; Grimmer, Andrew J; Earley, Ryan L; Canario, Adelino V M; Wilson, Alastair J; Walling, Craig A

    2015-02-01

    It is widely expected that physiological and behavioral stress responses will be integrated within divergent stress-coping styles (SCS) and that these may represent opposite ends of a continuously varying reactive-proactive axis. If such a model is valid, then stress response traits should be repeatable and physiological and behavioral responses should also change in an integrated manner along a major axis of among-individual variation. While there is some evidence of association between endocrine and behavioral stress response traits, few studies incorporate repeated observations of both. To test this model, we use a multivariate, repeated measures approach in a captive-bred population of Xiphophorus birchmanni. We quantify among-individual variation in behavioral stress response to an open field trial (OFT) with simulated predator attack (SPA) and measure waterborne steroid hormone levels (cortisol, 11-ketotestosterone) before and after exposure. Under the mild stress stimulus (OFT), (multivariate) behavioral variation among individuals was consistent with a strong axis of personality (shy-bold) or coping style (reactive-proactive) variation. However, behavioral responses to a moderate stressor (SPA) were less repeatable, and robust statistical support for repeatable endocrine state over the full sampling period was limited to 11-ketotestosterone. Although post hoc analysis suggested cortisol expression was repeatable over short time periods, qualitative relationships between behavior and glucocorticoid levels were counter to our a priori expectations. Thus, while our results clearly show among-individual differences in behavioral and endocrine traits associated with stress response, the correlation structure between these is not consistent with a simple proactive-reactive axis of integrated stress-coping style. Additionally, the low repeatability of cortisol suggests caution is warranted if single observations (or indeed repeat measures over short sampling

  20. Stress generation in adolescence: Contributions from five-factor model (FFM) personality traits and childhood maltreatment.

    Science.gov (United States)

    Kushner, Shauna C; Bagby, R Michael; Harkness, Kate L

    2017-04-01

    Youth with depression are theorized to generate stress in their lives because of a complex interaction between their personal characteristics and their chronic environmental context. Using a moderated regression approach, we provided a novel test of this hypothesis by examining whether adolescent 5-factor model personality traits moderate the associations between early emotional, physical, and sexual maltreatment and life events experienced in the past 6 months. Participants in this cross-sectional study were 110 adolescents (M = 16.24, SD = 1.53, age range = 13-17, 74.5% female) with major depressive disorder. The relation of physical maltreatment to dependent interpersonal life events was moderated by extraversion. Among physically maltreated youth, dependent interpersonal events were positively associated with extraversion. Further, the relation of sexual maltreatment to independent events were moderated by extraversion and agreeableness. Among sexually maltreated youth, independent events were negatively associated with extraversion and positively associated with agreeableness. The observed vulnerability-risk interactions are discussed in terms of their implications for understanding the role of stress generation mechanisms in an integrated model of depression. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Trait hostility and ambulatory blood pressure among traffic enforcement agents: the effects of stressful social interactions.

    Science.gov (United States)

    Brondolo, Elizabeth; Grantham, Kamau Imarogbe; Karlin, William; Taravella, Joseph; Mencía-Ripley, Aida; Schwartz, Joseph E; Pickering, Thomas G; Contrada, Richard J

    2009-04-01

    This study investigated the hypothesis that trait hostility is associated with heightened cardiovascular reactivity to potentially stressful social interactions but not to nonsocial activities in the workplace. Participants were 73 (39 women) New York City traffic enforcement agents (TEAs) who patrol the streets and issue summonses for vehicular and parking violations. During their patrols, TEAs face potentially stressful interactions when they encounter motorists and pedestrians who may be angry about receiving summonses. Mood and ambulatory blood pressure were initially measured when TEAs were recently hired and attending classes at the training academy (Time 1), and were subsequently assessed again once the TEAs began independently patrolling the city streets (Time 2). Random effects regression models yielded a significant interaction of hostility and work activity on ambulatory systolic blood pressure at Time 2. For those high in hostility, but not for those low in hostility, systolic blood pressure levels were higher while interacting with members of the public than during nonsocial work activities. The findings support the notion that situational factors affect the association of hostility to cardiovascular reactivity, and that interpersonal stressors in the workplace elicit cardiovascular activation among those high in hostility.

  2. Simulating Plant Water Stress and Phenology in Seasonally Dry Tropical Forests: Plant Hydraulics and Trait-Driven Trade-Offs

    Science.gov (United States)

    Xu, X.; Medvigy, D.; Powers, J. S.; Becknell, J. M.

    2014-12-01

    Seasonally dry tropical forests account for over 40% of the forested area in tropical and subtropical regions. Previous studies suggest that seasonal water stress is one main driver of phenology and related vegetation dynamics in seasonally dry tropical forests. Species that coexist in seasonally dry tropical forests have different plant traits, experience different degrees of plant water stress and show distinctive phenological patterns. However, the observed diversity in plant phenology and related vegetation dynamics is poorly represented in current dynamic vegetation models. In this study, we employ a new modeling approach to enhance our model skills in seasonally dry tropical forests. First, we implement a new plant hydraulic module under the framework of a state-of-the-art dynamic vegetation model, Ecosystem Demography 2 (ED2). Second, we link plant water stress with several key coordinated plant traits. Unlike previous models, the updated ED2 does not prescribe leaf phenology (deciduous or evergreen) and plant water stress is not determined by empirical water stress factors or by soil moisture alone. Instead, the model tracks more mechanistic indicators of plant water stress like leaf water potential, accounts for different abilities to tolerate water stress among plant functional types and predicts dry season leaf deciduousness and related vegetation dynamics. The updated model is then tested with in-situ meteorological data and long-term ecological observations. We also perform numerical experiments to explore the possible biases of ignoring the observed diversity in seasonally dry tropical forests. We find that (i) variations of several key plant traits (specific leaf area, wood density, turgor loss point and rooting depth) can account for the observed distinctive phenological patterns as well as inter-annual variations in vegetation growth among species. (ii) Ignoring the trait-driven trade-offs and diversity in seasonality would introduce significant

  3. Endoplasmic reticulum stress in insulin resistance and diabetes.

    Science.gov (United States)

    Guerrero-Hernández, Agustin; Leon-Aparicio, Daniel; Chavez-Reyes, Jesus; Olivares-Reyes, Jesus A; DeJesus, Silvia

    2014-11-01

    The endoplasmic reticulum is the main intracellular Ca(2+) store for Ca(2+) release during cell signaling. There are different strategies to avoid ER Ca(2+) depletion. Release channels utilize first Ca(2+)-bound to proteins and this minimizes the reduction of the free luminal [Ca(2+)]. However, if release channels stay open after exhaustion of Ca(2+)-bound to proteins, then the reduction of the free luminal ER [Ca(2+)] (via STIM proteins) activates Ca(2+) entry at the plasma membrane to restore the ER Ca(2+) load, which will work provided that SERCA pump is active. Nevertheless, there are several noxious conditions that result in decreased activity of the SERCA pump such as oxidative stress, inflammatory cytokines, and saturated fatty acids, among others. These conditions result in a deficient restoration of the ER [Ca(2+)] and lead to the ER stress response that should facilitate recovery of the ER. However, if the stressful condition persists then ER stress ends up triggering cell death and the ensuing degenerative process leads to diverse pathologies; particularly insulin resistance, diabetes and several of the complications associated with diabetes. This scenario suggests that limiting ER stress should decrease the incidence of diabetes and the mobility and mortality associated with this illness. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Exercise, learned helplessness, and the stress-resistant brain.

    Science.gov (United States)

    Greenwood, Benjamin N; Fleshner, Monika

    2008-01-01

    Exercise can prevent the development of stress-related mood disorders, such as depression and anxiety. The underlying neurobiological mechanisms of this effect, however, remain unknown. Recently, researchers have used animal models to begin to elucidate the potential mechanisms underlying the protective effects of physical activity. Using the behavioral consequences of uncontrollable stress or "learned helplessness" as an animal analog of depression- and anxiety-like behaviors in rats, we are investigating factors that could be important for the antidepressant and anxiolytic properties of exercise (i.e., wheel running). The current review focuses on the following: (1) the effect of exercise on the behavioral consequences of uncontrollable stress and the implications of these effects on the specificity of the "learned helplessness" animal model; (2) the neurocircuitry of learned helplessness and the role of serotonin; and (3) exercise-associated neural adaptations and neural plasticity that may contribute to the stress-resistant brain. Identifying the mechanisms by which exercise prevents learned helplessness could shed light on the complex neurobiology of depression and anxiety and potentially lead to novel strategies for the prevention of stress-related mood disorders.

  5. Impact of psychological stress on the associations between apolipoprotein E variants and metabolic traits: findings in an American sample of caregivers and controls.

    Science.gov (United States)

    Kring, Sofia I Iqbal; Brummett, Beverly H; Barefoot, John; Garrett, Melanie E; Ashley-Koch, Allison E; Boyle, Stephen H; Siegler, Ilene C; Sørensen, Thorkild I A; Williams, Redford B

    2010-06-01

    To examine the association between apolipoprotein E (APOE) gene variants and waist circumference, fasting plasma glucose, serum insulin, serum high-density lipoprotein cholesterol, and serum triglycerides, all metabolic traits known as cardiovascular disease (CVD) endophenotypes, in a population of stressed individuals and controls. Abdominal obesity, insulin resistance, elevated serum lipid concentration, and APOE polymorphisms have been associated with CVD risk. Current evidence supports the hypothesis that gene-environment interactions modulate serum lipid concentrations. The association between rs769450, rs405509, rs439401, and metabolic traits were analyzed in a U.S. sample of 126 white caregivers of a relative with Alzheimer';s disease or other major dementia and 122 white controls. The associations were analyzed, using multivariate analysis of variance adjusted for age, sex, and medications. Significant multivariate interactions were found, using both additive (p = .009) and dominant (p = .047) models between rs439401 (C/T) and caregiver stress in relation to a profile of metabolic variables. Univariate analyses found the TT genotype to be associated with more adverse levels of waist circumference (interaction, p = .026), triglycerides (interaction, p = .001) and high-density lipoprotein cholesterol (interaction, p = .001) among caregivers but with a more favorable profile of these endophenotypes among controls. There were no significant associations or interactions involving the other two single nucleotide polymorphisms. The APOE rs439401 TT genotype is associated with an adverse metabolic profile among chronically stressed individuals compared with individuals not similarly stressed in whom a more favorable profile is expressed. Confirmation of these results in further research would indicate that the TT genotype can be used to identify persons at high risk for CVD when subjected to chronic stress.

  6. Chronic environmental stress and the temporal course of depression and panic disorder: A trait-state-occasion modeling approach.

    Science.gov (United States)

    Conway, Christopher C; Rutter, Lauren A; Brown, Timothy A

    2016-01-01

    Both acute stressful life events and ongoing strains are thought to confer vulnerability to emotional disorders. Unremitting stressful conditions may be particularly pathogenic, but prior research has struggled to delimit chronic versus transient stressful experiences. We aimed to isolate stable stressors-theorized to be indicators of a latent stress proneness trait-and to examine their effects on the temporal course of depression and panic disorder. We recruited 677 patients diagnosed with an emotional disorder and administered interviews for psychopathology and life stress 3 times over 12-month intervals. Trait-state-occasion modeling revealed that 74% of the variance in life stress was stable over the follow-up period. These stable stressors were associated with a more refractory course of depression and, to a smaller degree, panic disorder over time. In addition, neither gender nor participation in cognitive-behavioral therapy affected the persistence of environmental stress over the study time frame. We discuss implications of these findings for explaining depression recurrence, improving psychological interventions for emotional disorders, and the measurement and evaluation of stress proneness. (c) 2016 APA, all rights reserved.

  7. Dopamine response to psychosocial stress in humans and its relationship to individual differences in personality traits.

    Science.gov (United States)

    Suridjan, Ivonne; Boileau, Isabelle; Bagby, Michael; Rusjan, Pablo M; Wilson, Alan A; Houle, Sylvain; Mizrahi, Romina

    2012-07-01

    Previous studies have reported inter-individual variability in the dopamine (DA) response to stress. This variability might be related to individual differences in the vulnerability to experience the negative effect of stress. To investigate whether personality traits as measured by the revised NEO personality inventory explain variability in DA response to a psychosocial stress task. Eleven healthy adults, mean age of 26 ± 3.87 underwent two positron emission tomography (PET) scans using the dopamine D(2/3) agonist, [11C]-(+)-PHNO under a control and stress condition. The simplified reference tissue model (SRTM) was used to obtain [11C]-(+)-PHNO binding potential (BP(ND)). Stress-induced DA response was indexed as a percent change in [11C]-(+)-PHNO BP(ND) between control and stress conditions. The regions of interest were defined into D2-rich regions, which included the Associative and Sensorimotor Striatum (AST and SMST); D(2/3) mixed regions, which included the limbic striatum (LST) and globus pallidus (GP); and D3-rich region, which included the Substantia Nigra (SN). Several personality traits within the Neuroticism and Openness to Experience domain were significantly correlated with blunted DA response to stress. Specifically, the Angry-Hostility, Vulnerability, and Depression trait were associated with blunted DA stress response in the AST (r = -0.645, p = 0.032), LST (r = -0.677, p = 0.022) and GP (r = -0.736, p = 0.010), respectively. The Openness to Values was correlated with a decreased DA release in the SN (r = -0.706, p = 0.015). Variability in DA stress response might be related to individual differences in personality. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  8. Resistance of oxidative stress in biofilm and planktonic cells

    Directory of Open Access Journals (Sweden)

    Witold Jakubowski

    2015-04-01

    Full Text Available This work studied the susceptibility of biofilm produced by E. coli to oxidative stress, and compared the components of free radicals defences: level of glutathione, catalase and dismutase activities in planktonic and biofilm located cells. Results showed the diversity of responses to oxidative stress in bacterial cells in log or stationary phases in both planktonic and biofilm forms. The bacteria were exposed to free-radical donors (H2O2, tBOOH, menadione, SIN-1 or peroxynitrite in a wide range of final concentrations, from 0.5 to 10mM. Different level of toxicity of individual donors, independence of cell type (planktonic forms or biofilm and phases of growth were observed. The highest oxidative stress resistance was observed for the cells in logarithmic phase of growth treated with H2O2, both in planktonic and biofilm forms, whereas for the cells in stationary phase, the highest resistance was observed for menadione. These results showed higher efficiency of agents based on superoxide anion donors in combating bacteria colonizing abiotic surfaces stainless steel (AISI 316L.

  9. Cellular memory of acquired stress resistance in Saccharomyces cerevisiae.

    Science.gov (United States)

    Guan, Qiaoning; Haroon, Suraiya; Bravo, Diego González; Will, Jessica L; Gasch, Audrey P

    2012-10-01

    Cellular memory of past experiences has been observed in several organisms and across a variety of experiences, including bacteria "remembering" prior nutritional status and amoeba "learning" to anticipate future environmental conditions. Here, we show that Saccharomyces cerevisiae maintains a multifaceted memory of prior stress exposure. We previously demonstrated that yeast cells exposed to a mild dose of salt acquire subsequent tolerance to severe doses of H(2)O(2). We set out to characterize the retention of acquired tolerance and in the process uncovered two distinct aspects of cellular memory. First, we found that H(2)O(2) resistance persisted for four to five generations after cells were removed from the prior salt treatment and was transmitted to daughter cells that never directly experienced the pretreatment. Maintenance of this memory did not require nascent protein synthesis after the initial salt pretreatment, but rather required long-lived cytosolic catalase Ctt1p that was synthesized during salt exposure and then distributed to daughter cells during subsequent cell divisions. In addition to and separable from the memory of H(2)O(2) resistance, these cells also displayed a faster gene-expression response to subsequent stress at >1000 genes, representing transcriptional memory. The faster gene-expression response requires the nuclear pore component Nup42p and serves an important function by facilitating faster reacquisition of H(2)O(2) tolerance after a second cycle of salt exposure. Memory of prior stress exposure likely provides a significant advantage to microbial populations living in ever-changing environments.

  10. l-Arginine Enhances Resistance against Oxidative Stress and Heat Stress in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Heran Ma

    2016-09-01

    Full Text Available The antioxidant properties of l-arginine (l-Arg in vivo, and its effect on enhancing resistance to oxidative stress and heat stress in Caenorhabditis elegans were investigated. C. elegans, a worm model popularly used in molecular and developmental biology, was used in the present study. Here, we report that l-Arg, at a concentration of 1 mM, prolonged C. elegans life by 26.98% and 37.02% under oxidative and heat stress, respectively. Further experiments indicated that the longevity-extending effects of l-Arg may be exerted by its free radical scavenging capacity and the upregulation of aging-associated gene expression in worms. This work is important in the context of numerous recent studies that concluded that environment stresses are associated with an increased population death rate.

  11. Identification of quantitative trait loci for body temperature, body weight, breast yield, and digestibility in an advanced intercross line of chickens under heat stress.

    Science.gov (United States)

    Van Goor, Angelica; Bolek, Kevin J; Ashwell, Chris M; Persia, Mike E; Rothschild, Max F; Schmidt, Carl J; Lamont, Susan J

    2015-12-17

    Losses in poultry production due to heat stress have considerable negative economic consequences. Previous studies in poultry have elucidated a genetic influence on response to heat. Using a unique chicken genetic resource, we identified genomic regions associated with body temperature (BT), body weight (BW), breast yield, and digestibility measured during heat stress. Identifying genes associated with a favorable response during high ambient temperature can facilitate genetic selection of heat-resilient chickens. Generations F18 and F19 of a broiler (heat-susceptible) × Fayoumi (heat-resistant) advanced intercross line (AIL) were used to fine-map quantitative trait loci (QTL). Six hundred and thirty-one birds were exposed to daily heat cycles from 22 to 28 days of age, and phenotypes were measured before heat treatment, on the 1st day and after 1 week of heat treatment. BT was measured at these three phases and BW at pre-heat treatment and after 1 week of heat treatment. Breast muscle yield was calculated as the percentage of BW at day 28. Ileal feed digestibility was assayed from digesta collected from the ileum at day 28. Four hundred and sixty-eight AIL were genotyped using the 600 K Affymetrix chicken SNP (single nucleotide polymorphism) array. Trait heritabilities were estimated using an animal model. A genome-wide association study (GWAS) for these traits and changes in BT and BW was conducted using Bayesian analyses. Candidate genes were identified within 200-kb regions around SNPs with significant association signals. Heritabilities were low to moderate (0.03 to 0.35). We identified QTL for BT on Gallus gallus chromosome (GGA)14, 15, 26, and 27; BW on GGA1 to 8, 10, 14, and 21; dry matter digestibility on GGA19, 20 and 21; and QTL of very large effect for breast muscle yield on GGA1, 15, and 22 with a single 1-Mb window on GGA1 explaining more than 15% of the genetic variation. This is the first study to estimate heritabilities and perform GWAS using this

  12. Identification of QTLs Associated with Virulence Related Traits and Drug Resistance in Cryptococcus neoformans

    Directory of Open Access Journals (Sweden)

    Aaron A. Vogan

    2016-09-01

    Full Text Available Cryptococcus neoformans is a basidiomycete fungus capable of causing deadly meningoenchephilitis, primarily in immunocompromised individuals. Formerly, C. neoformans was composed of two divergent lineages, but these have recently been elevated to species status, now C. neoformans (formerly C. neoformans var. grubii and C. deneoformans (formerly C. neoformans var. neoformans. While both species can cause deadly infections in humans, C. neoformans is much more prevalent in clinical settings than C. deneoformans. However, the genetic factors contributing to their significant differences in virulence remain largely unknown. Quantitative trait locus (QTL mapping is a powerful tool that can be used to identify genomic regions associated with phenotypic differences between strains. Here, we analyzed a hybrid cross between these two species and identified a total of 23 QTL, including five for melanin production, six for cell size, one for cell wall thickness, five for the frequency of capsule production, three for minimal inhibitory concentration (MIC of fluconazole in broth, and three for MIC on solid medium. For the fluconazole resistance-associated QTL, three showed environment and/or concentration-specific effects. Our results provide a large number of candidate gene regions from which to explore the molecular bases for phenotypic differences between C. neoformans and C. deneoformans.

  13. Farmers’ Perceptions and Knowledge of Cattle Adaptation to Heat Stress and Tick Resistance in the Eastern Cape, South Africa

    Science.gov (United States)

    Katiyatiya, C. L. F.; Muchenje, V.; Mushunje, A.

    2014-01-01

    The objective of this study was to determine the perceptions and knowledge of farmers of heat stress and tick resistance in cattle. A cross-sectional survey was conducted and 110 farmers in four villages in the sour and sweet velds of the Eastern Cape Province, South Africa were interviewed. The associations among area (municipality), gender, age, level of education, employment and religion were computed using Chi-square tests. The majority of the respondents had on average 4 bulls, 4 cows, 4 heifers, 4 calves, and 4 oxen. Milk was considered as the major (28.3%) reason for keeping cattle. Most farmers owned non-descript (72.6%), and Nguni (45.3%) cattle because of their heat tolerance (54.7%), tick resistance (54.7%), and milking ability (28.2%) traits. Excessive panting (56.6%) and disease transmission (76%) were regarded as the major effects of heat stress and tick infestation in cattle, respectively. About 50% of the respondents agreed that hair length influences tick resistance and 47.17% considered coat colour when acquiring cattle. In the sampled areas, ticks were prevalent in the summer season (93%), and 77.36% of the respondents use acaricides every fortnight. Gall sickness was reported to be a major problem in the cattle herds by 36.79% of the respondents. Our results showed that farmers in the two municipalities had knowledge of cattle adaptation to heat stress and tick resistance. PMID:25358328

  14. Farmers’ Perceptions and Knowledge of Cattle Adaptation to Heat Stress and Tick Resistance in the Eastern Cape, South Africa

    Directory of Open Access Journals (Sweden)

    C. L. F. Katiyatiya

    2014-11-01

    Full Text Available The objective of this study was to determine the perceptions and knowledge of farmers of heat stress and tick resistance in cattle. A cross-sectional survey was conducted and 110 farmers in four villages in the sour and sweet velds of the Eastern Cape Province, South Africa were interviewed. The associations among area (municipality, gender, age, level of education, employment and religion were computed using Chi-square tests. The majority of the respondents had on average 4 bulls, 4 cows, 4 heifers, 4 calves, and 4 oxen. Milk was considered as the major (28.3% reason for keeping cattle. Most farmers owned non-descript (72.6%, and Nguni (45.3% cattle because of their heat tolerance (54.7%, tick resistance (54.7%, and milking ability (28.2% traits. Excessive panting (56.6% and disease transmission (76% were regarded as the major effects of heat stress and tick infestation in cattle, respectively. About 50% of the respondents agreed that hair length influences tick resistance and 47.17% considered coat colour when acquiring cattle. In the sampled areas, ticks were prevalent in the summer season (93%, and 77.36% of the respondents use acaricides every fortnight. Gall sickness was reported to be a major problem in the cattle herds by 36.79% of the respondents. Our results showed that farmers in the two municipalities had knowledge of cattle adaptation to heat stress and tick resistance.

  15. Using functional traits to assess the resistance of subalpine grassland to trampling by mountain biking and hiking.

    Science.gov (United States)

    Pickering, Catherine Marina; Barros, Agustina

    2015-12-01

    Functional traits reflect plant responses to disturbance, including from visitor impacts. The impacts of mountain biking and hiking on functional composition were compared using a common experimental protocol in a subalpine grassland in the Australian Alps. The overlapping cover of all species was recorded two weeks after different intensities of hiking (200 and 500 passes) and mountain biking (none, 25, 75, 200 and 500 passes). Species' functional trait data were combined with their relative cover to calculate community trait weighted means for plant height, leaf area, percentage leaf dry matter content and Specific Leaf Area (SLA). Species such as Poa fawcettiae with larger leaves and SLA but lower dry weight content of leaves were more resistant to use, with differences between bikers and hikers only apparent at the highest levels of use tested. This differs from some vegetation communities in Europe where plants with smaller leaves were more resistant to hiking. More research using functional traits may account for differences in species responses to trampling. Managers of conservation areas used for hiking and biking need to minimise off trail use by both user groups. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. A genome-screen experiment to detect quantitative trait loci affecting resistance to facial eczema disease in sheep.

    Science.gov (United States)

    Phua, S H; Dodds, K G; Morris, C A; Henry, H M; Beattie, A E; Garmonsway, H G; Towers, N R; Crawford, A M

    2009-02-01

    Facial eczema (FE) is a secondary photosensitization disease arising from liver cirrhosis caused by the mycotoxin sporidesmin. The disease affects sheep, cattle, deer and goats, and costs the New Zealand sheep industry alone an estimated NZ$63M annually. A long-term sustainable solution to this century-old FE problem is to breed for disease-resistant animals by marker-assisted selection. As a step towards finding a diagnostic DNA test for FE sensitivity, we have conducted a genome-scan experiment to screen for quantitative trait loci (QTL) affecting this trait in Romney sheep. Four F(1) sires, obtained from reciprocal matings of FE resistant and susceptible selection-line animals, were used to generate four outcross families. The resulting half-sib progeny were artificially challenged with sporidesmin to phenotype their FE traits measured in terms of their serum levels of liver-specific enzymes, namely gamma-glutamyl transferase and glutamate dehydrogenase. In a primary screen using selective genotyping on extreme progeny of each family, a total of 244 DNA markers uniformly distributed over all 26 ovine autosomes (with an autosomal genome coverage of 79-91%) were tested for linkage to the FE traits. Data were analysed using Haley-Knott regression. The primary screen detected one significant and one suggestive QTL on chromosomes 3 and 8 respectively. Both the significant and suggestive QTL were followed up in a secondary screen where all progeny were genotyped and analysed; the QTL on chromosome 3 was significant in this analysis.

  17. Anti-stress effect of theanine on students during pharmacy practice: positive correlation among salivary α-amylase activity, trait anxiety and subjective stress.

    Science.gov (United States)

    Unno, Keiko; Tanida, Naoki; Ishii, Naoto; Yamamoto, Hiroyuki; Iguchi, Kazuaki; Hoshino, Minoru; Takeda, Atsushi; Ozawa, Hayato; Ohkubo, Tsutomu; Juneja, Lekh Raj; Yamada, Hiroshi

    2013-10-01

    Theanine, an amino acid in tea, has significant anti-stress effect on experimental animals under psychosocial stress. Anti-stress effect of theanine on humans was evaluated in 5th-year university students during pharmacy practice. The study design was a single-blind group comparison and participants (n=20) were randomly assigned to theanine or placebo groups. Theanine or placebo (lactose) tablets (200 mg, twice a day, after breakfast and lunch) were taken from 1 week prior to the pharmacy practice and continued for 10 days in the practice period. To assess the anxiety of the participants, the state-trait anxiety inventory test was carried out before the pharmacy practice. Salivary α-amylase activity (sAA) was measured as a marker of sympathetic nervous system activity. In the placebo-group, sAA in the morning (pre-practice sAA) was higher than in theanine-group during the pharmacy practice (p=0.032). Subjective stress was significantly lower in the theanine-group than in the placebo-group (p=0.020). These results suggest that theanine intake had anti-stress effect on students. Furthermore, students with higher pre-practice sAA showed significantly higher trait anxiety in both groups (p=0.015). Similarly, higher pre-practice sAA was correlated to shorter sleeping time in both groups (p=0.41×10(-3)). Stressful condition increased the level of sAA that was essentially affected by individual trait anxiety. The low levels of pre-practice sAA and subjective stress in the theanine-group suggest that theanine intake suppressed initial stress response of students assigned for a long-term commitment of pharmacy practice. © 2013. Published by Elsevier Inc. All rights reserved.

  18. The Candida albicans Histone Acetyltransferase Hat1 Regulates Stress Resistance and Virulence via Distinct Chromatin Assembly Pathways.

    Directory of Open Access Journals (Sweden)

    Michael Tscherner

    2015-10-01

    Full Text Available Human fungal pathogens like Candida albicans respond to host immune surveillance by rapidly adapting their transcriptional programs. Chromatin assembly factors are involved in the regulation of stress genes by modulating the histone density at these loci. Here, we report a novel role for the chromatin assembly-associated histone acetyltransferase complex NuB4 in regulating oxidative stress resistance, antifungal drug tolerance and virulence in C. albicans. Strikingly, depletion of the NuB4 catalytic subunit, the histone acetyltransferase Hat1, markedly increases resistance to oxidative stress and tolerance to azole antifungals. Hydrogen peroxide resistance in cells lacking Hat1 results from higher induction rates of oxidative stress gene expression, accompanied by reduced histone density as well as subsequent increased RNA polymerase recruitment. Furthermore, hat1Δ/Δ cells, despite showing growth defects in vitro, display reduced susceptibility to reactive oxygen-mediated killing by innate immune cells. Thus, clearance from infected mice is delayed although cells lacking Hat1 are severely compromised in killing the host. Interestingly, increased oxidative stress resistance and azole tolerance are phenocopied by the loss of histone chaperone complexes CAF-1 and HIR, respectively, suggesting a central role for NuB4 in the delivery of histones destined for chromatin assembly via distinct pathways. Remarkably, the oxidative stress phenotype of hat1Δ/Δ cells is a species-specific trait only found in C. albicans and members of the CTG clade. The reduced azole susceptibility appears to be conserved in a wider range of fungi. Thus, our work demonstrates how highly conserved chromatin assembly pathways can acquire new functions in pathogenic fungi during coevolution with the host.

  19. Characterization of multifarious plant growth promoting traits of rhizobacterial strain AR6 under Chromium (VI) stress.

    Science.gov (United States)

    Karthik, Chinnannan; Elangovan, Namasivayam; Kumar, Thamilarasan Senthil; Govindharaju, Subramani; Barathi, Selvaraj; Oves, Mohammad; Arulselvi, Padikasan Indra

    2017-11-01

    Plant growth promoting rhizobacteria (PGPR) can increase the host plant tolerance to cope up with heavy metal induced stress, which can be improve plant growth. Thus, the present study was designed to isolate Cr(VI) tolerant PGPR strain and evaluate its plant growth promoting (PGP) properties under Cr(VI) stress. Rhizobacterial strain AR6 was isolated from the rhizosphere of Phaseolus vulgaris L. and showed 99% homology with Cellulosimicrobium funkei (KM032184) in BLASTn analysis. Strain AR6 was specifically selected due to its high Cr(VI) tolerance (1200μg/ml) and substantial production of PGP substances. Strain AR6 produced 36.75μg/ml of indole acetic acid (IAA), 60.40μg/ml of ammonia and 14.23μg/ml of exopolysaccharide (EPS). Moreover, strain AR6 showed positive results for catalase, protease, amylase, lipase production and phosphate solubilization. A trend of Cr(VI) concentration dependent progressive decline for PGP traits of strain AR6 was observed excluding EPS which was regularly increased on increasing concentrations of Cr(VI). Among the four tested Cr(VI) concentrations, 250μg/ml showed the maximum toxicity to PGP activities of strain AR6. Inoculation of rhizobacterial strain AR6 significantly increased the root length of test crops in the presence of Cr(VI) and produced a considerable number of colonizes on the root of versatile dicot and monocot plants. Moreover, strain AR6 exhibited strong antagonistic activity against phytopathogen Aspergillus niger. Thus, the present study suggests that metal tolerant and PGP activities of the rhizobacterial strain AR6 could be exploited for environmental and agricultural issues. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Cortical and Autonomic Stress Responses in Adults with High Versus Low Levels of Trait Anxiety: A Pilot Study.

    Science.gov (United States)

    Brugnera, A; Zarbo, C; Adorni, R; Compare, A; Sakatani, K

    2017-01-01

    Stress responses are mediated by complex patterns of cortical and autonomic activity. Earlier studies showed increased recruitment of the right prefrontal cortex (PFC) and parasympathetic withdrawal during a stress task; however, it remains unclear whether these responses change in relation to different levels of psychopathological symptoms, such as trait anxiety. The present study examines the effect of a mathematical task (with a control condition and a stressful/experimental condition) on the PFC and autonomic activity, using a two-channel near infrared spectroscopy (NIRS) and an ECG monitoring system. After a preliminary screening of 65 subjects, a sample of 12 individuals (6 with the highest and 6 with the lowest scores on an anxiety questionnaire, i.e. the STAI trait) was selected. The two groups were similar regarding demographic variables (age, sex, body mass index) and baseline STAI-state scores. Repeated measures ANOVAs were used to compare changes from baseline in oxyhemoglobin (oxy-Hb), heart rate (HR) and root mean square of successive differences (RMSSD) between the two groups. Individuals affected by high levels of trait anxiety showed a reduced bilateral PFC activity during the entire experimental procedure compared to those with low anxiety. No differences in NIRS channels were found between the two groups. During both conditions, RMSSD was lower among individuals affected by high levels of anxious symptoms. Finally, throughout the procedure, changes in HR were higher in the anxious group. Overall, these findings suggest a reduced PFC activity and a larger parasympathetic withdrawal during a stress task in individuals with high levels of trait anxiety compared to those with low anxiety. These results could represent a starting point for future NIRS and ECG studies on the relationship between mental disorders and acute stress responses.

  1. Stress-Induced Evolution of Heat Resistance and Resuscitation Speed in Escherichia coli O157:H7 ATCC 43888.

    Science.gov (United States)

    Gayán, Elisa; Cambré, Alexander; Michiels, Chris W; Aertsen, Abram

    2016-11-15

    The development of resistance in foodborne pathogens to food preservation techniques is an issue of increasing concern, especially in minimally processed foods where safety relies on hurdle technology. In this context, mild heat can be used in combination with so-called nonthermal processes, such as high hydrostatic pressure (HHP), at lower individual intensities to better retain the quality of the food. However, mild stresses may increase the risk of (cross-)resistance development in the surviving population, which in turn might compromise food safety. In this investigation, we examined the evolution of Escherichia coli O157:H7 strain ATCC 43888 after recurrent exposure to progressively intensifying mild heat shocks (from 54.0°C to 60.0°C in 0.5°C increments) with intermittent resuscitation and growth of survivors. As such, mutant strains were obtained after 10 cycles of selection with ca. 106-fold higher heat resistance than that for the parental strain at 58.0°C, although this resistance did not extend to temperatures exceeding 60.0°C. Moreover, these mutant strains typically displayed cross-resistance against HHP shock and displayed signs of enhanced RpoS and RpoH activity. Interestingly, additional cycles of selection maintaining the intensity of the heat shock constant (58.5°C) selected for mutant strains in which resuscitation speed, rather than resistance, appeared to be increased. Therefore, it seems that resistance and resuscitation speed are rapidly evolvable traits in E. coli ATCC 43888 that can compromise food safety. In this investigation, we demonstrated that Escherichia coli O157:H7 ATCC 43888 rapidly acquires resistance to mild heat exposure, with this resistance yielding cross-protection to high hydrostatic pressure treatment. In addition, mutants of E. coli ATCC 43888 in which resuscitation speed, rather than resistance, appeared to be improved were selected. As such, both resistance and resuscitation speed seem to be rapidly evolvable

  2. Effects of Humic Acid on the Germination Traits of Pumpkin Seeds under Cadmium Stress

    Directory of Open Access Journals (Sweden)

    Maasoumeh ASADI

    2013-12-01

    Full Text Available The study tackled the effect of humic acid and cadmium concentrations on the pumpkin seed germination characteristics throughout were studied. Treatments were cadmium concentrations on three levels: 0, 100 and 200 ppm and humic acid concentration of 0, 100, 200, 300 and 400 mg lit-1. Results showed that interaction of humic acid and cadmium was not significant on germination traits, but there was a significant effect on seedling growth indexes. Radicle and plumule length increased by 86 and 192% in comparison with control, of the mixture of 200 ppm cadmium and 300 mg lit-1 of humic acid. Cadmium had stimulatory effect on radicle and cotyledon dry weight and the highest values obtained with 200 ppm in mixture with 200 mg lit-1 of humic acid. Also, maximum plumule dry weight was recorded in 200 ppm cadmium and 300 mg lit-1 of humic acid. The highest of indexes were observed of 200 ppm cadmium and 400 mg lit-1 humic acid. In conclusion, the humic acid had detoxifying effect on cadmium stress in the culture and responded antagonistically against cadmium, but it seems that these concentrations of cadmium are low for the pumpkin seed and can be increased in order to reach the toxicity level.

  3. Arbutin increases Caenorhabditis elegans longevity and stress resistance

    Directory of Open Access Journals (Sweden)

    Lin Zhou

    2017-12-01

    Full Text Available Arbutin (p-hydroxyphenyl-β-D-glucopyranoside, a well-known tyrosinase inhibitor, has been widely used as a cosmetic whitening agent. Although its natural role is to scavenge free radicals within cells, it has also exhibited useful activities for the treatment of diuresis, bacterial infections and cancer, as well as anti-inflammatory and anti-tussive activities. Because function of free radical scavenging is also related to antioxidant and the effects of arbutin on longevity and stress resistance in animals have not yet been confirmed, here the effects of arbutin on Caenorhabditis elegans were investigated. The results demonstrated that optimal concentrations of arbutin could extend lifespan and enhance resistance to oxidative stress. The underlying molecular mechanism for these effects involves decreased levels of reactive oxygen species (ROS, improvement of daf-16 nuclear localization, and up-regulated expression of daf-16 and its downstream targets, including sod-3 and hsp16.2. In this work the roles of arbutin in lifespan and health are studied and the results support that arbutin is an antioxidant for maintaining overall health.

  4. Responses to combined abiotic and biotic stress in tomato are governed by stress intensity and resistance mechanism

    NARCIS (Netherlands)

    Kissoudis, Christos; Sri Sunarti, Sri; De Wiel, Van Clemens; Visser, Richard G.F.; Linden, van der Gerard; Bai, Yuling

    2016-01-01

    Stress conditions in agricultural ecosystems can occur at variable intensities. Different resistance mechanisms against abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the

  5. Supplementary data: Responses to combined abiotic and biotic stress in tomato are governed by stress intensity and mechanism of resistance

    NARCIS (Netherlands)

    Kissoudis, C.; Sri Sunarti, Sri; Wiel, van de C.C.M.; Visser, R.G.F.; Linden, van der C.G.; Bai, Y.

    2016-01-01

    Stress conditions in agricultural ecosystems can occur in variable intensities. Different resistance mechanisms to abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the effect of

  6. Detection of quantitative trait loci for resistance/susceptibility to pseudorabies virus in swine.

    Science.gov (United States)

    Reiner, Gerald; Melchinger, Elke; Kramarova, Marcela; Pfaff, Eberhardt; Büttner, Matthias; Saalmüller, Armin; Geldermann, Hermann

    2002-01-01

    This study describes genetic differences in resistance/susceptibility to pseudorabies virus (PrV) between European Large White and Chinese Meishan pigs, with a mapping of quantitative trait loci (QTL) obtained from a genome-wide scan in F(2) animals. Eighty-nine F(2) pigs were challenged intranasally at 12 weeks with 10(5) p.f.u. of the wild-type PrV strain NIA-3. For QTL analysis, 85 microsatellite markers, evenly spaced on the 18 porcine autosomes and on the pseudoautosomal region of the X chromosome, were genotyped. All pigs developed clinical signs, i.e. fever, from 3 to 7 days p.i. The pure-bred Large White pigs, the F(1) and three-quarters of the F(2) animals, but none of the Meishan pigs, developed neurological symptoms and died or were euthanized. QTLs for appearance/non-appearance of neurological symptoms were found on chromosomes 9, 5, 6 and 13. They explained 10.6-17.9% of F(2) phenotypic variance. QTL effects for rectal temperature after PrV challenge were found on chromosomes 2, 4, 8, 10, 11 and 16. Effects on chromosomes 9, 10 and 11 were significant on a genome-wide level. The results present chromosomal regions that are associated with presence/absence of neurological symptoms as well as temperature course after intranasal challenge with NIA-3. The QTLs are in proximity to important candidate genes that are assumed to play crucial roles in host defence against PrV.

  7. Effect of Salt Stress on Morphological Traits of Lettuce Genotypes (Lactuca Sativa L.

    Directory of Open Access Journals (Sweden)

    maryam zare

    2017-02-01

    Full Text Available Introduction: The recognition of salt tolerant plants is important as a result ofincreasing saline lands in Iran and world. Cultivation of plants in hydroponic environment is a reliable and economical method in order to select the salt tolerant plant. Salt stress can effect on plant growth and development by ion toxicity, ionic disturb the balance and osmotic potential. Lettuce is one of the most important vegetable crops. This plant is one of the most important leafy vegetables which is used for salad and fresh marketing, also some types of this vegetable is used in baked type. The aim of this study was to investigate the genetic diversity of lettuce genotypes undersalt stress in the hydroponic system. Materials and Methods: To assess response of lettuce seedlings to salt stress, a factorial experiment was conducted in a completely randomized design with three replications at Biotechnology Research Institute for hydroponic cultivation of Zabol. In this experiment, the effects of three salinity levels (0, 2 and 4 dS/m on morphological characteristics of 15 lettuce genotypes were evaluated. The seeds were sterilized for ten seconds in ethanol 96% and then 15% sodium hypochlorite solution for 50 seconds, then rinsed several times with distilled water, then disinfected seeds were cultured in plastic pots containing coco peat and perlite. After …days plants were transferred to hydroponic system containing Hoagland solution. Collected data were analyzed and means comparisons were made using LSD by SAS software. Results and Discussion: The results showed that salinity has a significant effect on seedling growth of lettuce genotypes (p≤0.01. significant difference between salinity levels and genotype were observed for all traits. Interaction of genotype and salinity for all the traits except root length, plant length and leaf were significant at 1%. Based on the results, the greatest root length was belong to Esfahan Varzaneh leafy lettuce and

  8. Proline, catalase and root traits as indices of drought resistance in ...

    African Journals Online (AJOL)

    The field experiment was grown during Sali season of 2007 to estimate the genetic variability of eight quantitative traits; root weight (g), number of primary roots, number of tillers/plant, root length (cm),shoot weight (g), root:shoot ratio by length and root:shoot ratio by weight. The data for the quantitative traits were recorded ...

  9. Evaluation and Exploration of Favorable QTL Alleles for Salt Stress Related Traits in Cotton Cultivars (G. hirsutum L..

    Directory of Open Access Journals (Sweden)

    Lei Du

    Full Text Available Soil salinization is one of the major problems in global agricultural production. Cotton is a pioneer crop with regard to salt stress tolerance, and can be used for saline-alkali land improvement. The large-scale detection of salt tolerance traits in cotton accessions, and the identification of elite quantitative trait loci (QTLs/genes for salt-tolerance have been very important in salt tolerance breeding. Here, 43 advanced salt-tolerant and 31 highly salt-sensitive cultivars were detected by analyzing ten salt tolerance related traits in 304 upland cotton cultivars. Among them, 11 advanced salt-tolerance and eight highly salt-sensitive cultivars were consistent with previously reported results. Association analysis of ten salt-tolerance related traits and 145 SSRs was performed, and a total of 95 significant associations were detected; 17, 41, and 37 of which were associated with germinative index, seedling stage physiological index, and four seedling stage biochemical indexes, respectively. Of these associations, 20 SSR loci were simultaneously associated with two or more traits. Furthermore, we detected 117 elite alleles associated with salt-tolerance traits, 4 of which were reported previously. Among these loci, 44 (37.60% were rare alleles with a frequency of less than 5%, 6 only existed in advanced salt-tolerant cultivars, and 2 only in highly salt-sensitive cultivars. As a result, 13 advanced salt-tolerant cultivars were selected to assemble the optimal cross combinations by computer simulation for the development of salt-tolerant accessions. This study lays solid foundations for further improvements in cotton salt-tolerance by referencing elite germplasms, alleles associated with salt-tolerance traits, and optimal crosses.

  10. The physiological determinants of drug-induced lysosomal stress resistance.

    Directory of Open Access Journals (Sweden)

    Tehetina Woldemichael

    Full Text Available Many weakly basic, lipophilic drugs accumulate in lysosomes and exert complex, pleiotropic effects on organelle structure and function. Thus, modeling how perturbations of lysosomal physiology affect the maintenance of lysosomal ion homeostasis is necessary to elucidate the key factors which determine the toxicological effects of lysosomotropic agents, in a cell-type dependent manner. Accordingly, a physiologically-based mathematical modeling and simulation approach was used to explore the dynamic, multi-parameter phenomenon of lysosomal stress. With this approach, parameters that are either directly involved in lysosomal ion transportation or lysosomal morphology were transiently altered to investigate their downstream effects on lysosomal physiology reflected by the changes they induce in lysosomal pH, chloride, and membrane potential. In addition, combinations of parameters were simultaneously altered to assess which parameter was most critical for recovery of normal lysosomal physiology. Lastly, to explore the relationship between organelle morphology and induced stress, we investigated the effects of parameters controlling organelle geometry on the restoration of normal lysosomal physiology following a transient perturbation. Collectively, our results indicate a key, interdependent role of V-ATPase number and membrane proton permeability in lysosomal stress tolerance. This suggests that the cell-type dependent regulation of V-ATPase subunit expression and turnover, together with the proton permeability properties of the lysosomal membrane, is critical to understand the differential sensitivity or resistance of different cell types to the toxic effects of lysosomotropic drugs.

  11. Multivariate Analysis of Grain Yield and Its Attributing Traits in Different Maize Hybrids Grown under Heat and Drought Stress

    Directory of Open Access Journals (Sweden)

    Fawad Ali

    2015-01-01

    Full Text Available This study was carried out to evaluate F1 single cross-maize hybrids in four crop growing seasons (2010–2012. Morphological traits and physiological parameters of twelve maize hybrids were evaluated (i to construct seed yield equation and (ii to determine grain yield attributing traits of well-performing maize genotype using a previously unexplored method of two-way hierarchical clustering. In seed yield predicting equation photosynthetic rate contributed the highest variation (46%. Principal component analysis data showed that investigated traits contributed up to 90.55% variation in dependent structure. From factor analysis, we found that factor 1 contributed 49.6% variation (P<0.05 with primary important traits (i.e., number of leaves per plant, plant height, stem diameter, fresh leaves weight, leaf area, stomata conductance, substomata CO2 absorption rate, and photosynthetic rate. The results of two-way hierarchical clustering demonstrated that Cluster III had outperforming genotype H12 (Sultan × Soneri along with its most closely related traits (photosynthetic rate, stomata conductance, substomata CO2 absorption rate, chlorophyll contents, leaf area, and fresh stem weight. Our data shows that H12 (Sultan × Soneri possessed the highest grain yield per plant under environmentally stress conditions, which are most likely to exist in arid and semiarid climatic conditions, such as in Pakistan.

  12. The Role of Oxidative Stress in the Longevity and Insecticide Resistance Phenotype of the Major Malaria Vectors Anopheles arabiensis and Anopheles funestus.

    Science.gov (United States)

    Oliver, Shüné V; Brooke, Basil D

    2016-01-01

    Oxidative stress plays numerous biological roles, both functional and pathological. The role of oxidative stress in various epidemiologically relevant biological traits in Anopheles mosquitoes is not well established. In this study, the effects of oxidative stress on the longevity and insecticide resistance phenotype in the major malaria vector species An. arabiensis and An. funestus were examined. Responses to dietary copper sulphate and hydrogen peroxide were used as proxies for the oxidative stress phenotype by determining the effect of copper on longevity and hydrogen peroxide lethal dose. Glutathione peroxidase and catalase activities were determined colorimetrically. Oxidative burden was quantified as protein carbonyl content. Changes in insecticide resistance phenotype were monitored by WHO bioassay. Insecticide resistant individuals showed an increased capacity for coping with oxidative stress, mediated by increased glutathione peroxidase and catalase activity. This effect was observed in both species, as well as in laboratory strains and F1 individuals derived from wild-caught An. funestus mothers. Phenotypic capacity for coping with oxidative stress was greatest in strains with elevated Cytochrome P450 activity. Synergism of oxidative stress defence enzymes by dietary supplementation with haematin, 3-Amino-1, 2, 4-triazole and Sodium diethyldithiocarbamate significantly increased pyrethroid-induced mortality in An. arabiensis and An. funestus. It is therefore concluded that defence against oxidative stress underlies the augmentation of the insecticide resistance phenotype associated with multiple blood-feeding. This is because multiple blood-feeding ultimately leads to a reduction of oxidative stress in insecticide resistant females, and also reduces the oxidative burden induced by DDT and pyrethroids, by inducing increased glutathione peroxidase activity. This study highlights the importance of oxidative stress in the longevity and insecticide resistance

  13. The Role of Oxidative Stress in the Longevity and Insecticide Resistance Phenotype of the Major Malaria Vectors Anopheles arabiensis and Anopheles funestus.

    Directory of Open Access Journals (Sweden)

    Shüné V Oliver

    Full Text Available Oxidative stress plays numerous biological roles, both functional and pathological. The role of oxidative stress in various epidemiologically relevant biological traits in Anopheles mosquitoes is not well established. In this study, the effects of oxidative stress on the longevity and insecticide resistance phenotype in the major malaria vector species An. arabiensis and An. funestus were examined. Responses to dietary copper sulphate and hydrogen peroxide were used as proxies for the oxidative stress phenotype by determining the effect of copper on longevity and hydrogen peroxide lethal dose. Glutathione peroxidase and catalase activities were determined colorimetrically. Oxidative burden was quantified as protein carbonyl content. Changes in insecticide resistance phenotype were monitored by WHO bioassay. Insecticide resistant individuals showed an increased capacity for coping with oxidative stress, mediated by increased glutathione peroxidase and catalase activity. This effect was observed in both species, as well as in laboratory strains and F1 individuals derived from wild-caught An. funestus mothers. Phenotypic capacity for coping with oxidative stress was greatest in strains with elevated Cytochrome P450 activity. Synergism of oxidative stress defence enzymes by dietary supplementation with haematin, 3-Amino-1, 2, 4-triazole and Sodium diethyldithiocarbamate significantly increased pyrethroid-induced mortality in An. arabiensis and An. funestus. It is therefore concluded that defence against oxidative stress underlies the augmentation of the insecticide resistance phenotype associated with multiple blood-feeding. This is because multiple blood-feeding ultimately leads to a reduction of oxidative stress in insecticide resistant females, and also reduces the oxidative burden induced by DDT and pyrethroids, by inducing increased glutathione peroxidase activity. This study highlights the importance of oxidative stress in the longevity and

  14. [Effects of low nitrogen stress on source-sink characters and grain-filling traits of different genotypes summer maize].

    Science.gov (United States)

    Lu, Hai-dong; Xue, Ji-quan; Ma, Guo-sheng; Zhang, Ren-he; Zhang, Xing-hua

    2010-05-01

    This paper studied the source-sink characters and grain-filling traits of six genotype summer maize varieties under 2 years (from 2007 to 2008) application of low dosage (105 kg x hm(-2)) and normal dosage (337.5 kg x hm(-2)) fertilizer nitrogen. Under low nitrogen stress, the population yield, leaf area index (LAI), source-sink characters, and grain-filling traits of test varieties differed significantly. The varieties tolerant to low nitrogen, e.g., Xianyu 335 and Zhengdan 958, had longer active grain-filling stage, higher maximum filling rate, longer duration of maximum LAI, and more harmonious sink-source relation; while less tolerant species, e.g., Shaandan 902 and Yuyu 22, had shorter active grain-filling hours, lower maximum filling rate, lower mass increment and LAI under maximum grain-filling rate after silking, and significantly decreased source supply capacity. Low nitrogen stress increased the yield difference among the test varieties significantly.

  15. Identification of a Putative Quantitative Trait Gene for Resistance to Obesity in Mice Using Transcriptome Analysis and Causal Inference Tests.

    Directory of Open Access Journals (Sweden)

    Akira Ishikawa

    Full Text Available It is still challenging to identify causal genes governing obesity. Pbwg1.5, a quantitative trait locus (QTL for resistance to obesity, was previously discovered from wild Mus musculus castaneus mice and was fine-mapped to a 2.1-Mb genomic region of mouse chromosome 2, where no known gene with an effect on white adipose tissue (WAT has been reported. The aim of this study was to identify a strong candidate gene for Pbwg1.5 by an integration approach of transcriptome analysis (RNA-sequencing followed by real-time PCR analysis and the causal inference test (CIT, a statistical method to infer causal relationships between diplotypes, gene expression and trait values. Body weight, body composition and biochemical traits were measured in F2 mice obtained from an intercross between the C57BL/6JJcl strain and a congenic strain carrying Pbwg1.5 on the C57BL/6JJcl background. The F2 mice showed significant diplotype differences in 12 traits including body weight, WAT weight and serum cholesterol/triglyceride levels. The transcriptome analysis revealed that Ly75, Pla2r1, Fap and Gca genes were differentially expressed in the liver and that Fap, Ifih1 and Grb14 were differentially expressed in WAT. However, CITs indicated statistical evidence that only the liver Ly75 gene mediated between genotype and WAT. Ly75 expression was negatively associated with WAT weight. The results suggested that Ly75 is a putative quantitative trait gene for the obesity-resistant Pbwg1.5 QTL discovered from the wild M. m. castaneus mouse. The finding provides a novel insight into a better understanding of the genetic basis for prevention of obesity.

  16. Identification of a Putative Quantitative Trait Gene for Resistance to Obesity in Mice Using Transcriptome Analysis and Causal Inference Tests.

    Science.gov (United States)

    Ishikawa, Akira

    2017-01-01

    It is still challenging to identify causal genes governing obesity. Pbwg1.5, a quantitative trait locus (QTL) for resistance to obesity, was previously discovered from wild Mus musculus castaneus mice and was fine-mapped to a 2.1-Mb genomic region of mouse chromosome 2, where no known gene with an effect on white adipose tissue (WAT) has been reported. The aim of this study was to identify a strong candidate gene for Pbwg1.5 by an integration approach of transcriptome analysis (RNA-sequencing followed by real-time PCR analysis) and the causal inference test (CIT), a statistical method to infer causal relationships between diplotypes, gene expression and trait values. Body weight, body composition and biochemical traits were measured in F2 mice obtained from an intercross between the C57BL/6JJcl strain and a congenic strain carrying Pbwg1.5 on the C57BL/6JJcl background. The F2 mice showed significant diplotype differences in 12 traits including body weight, WAT weight and serum cholesterol/triglyceride levels. The transcriptome analysis revealed that Ly75, Pla2r1, Fap and Gca genes were differentially expressed in the liver and that Fap, Ifih1 and Grb14 were differentially expressed in WAT. However, CITs indicated statistical evidence that only the liver Ly75 gene mediated between genotype and WAT. Ly75 expression was negatively associated with WAT weight. The results suggested that Ly75 is a putative quantitative trait gene for the obesity-resistant Pbwg1.5 QTL discovered from the wild M. m. castaneus mouse. The finding provides a novel insight into a better understanding of the genetic basis for prevention of obesity.

  17. Breeding of lager yeast with Saccharomyces cerevisiae improves stress resistance and fermentation performance.

    Science.gov (United States)

    Garcia Sanchez, Rosa; Solodovnikova, Natalia; Wendland, Jürgen

    2012-08-01

    Lager beer brewing relies on strains collectively known as Saccharomyces carlsbergensis, which are hybrids between S. cerevisiae and S. eubayanus-like strains. Lager yeasts are particularly adapted to low-temperature fermentations. Selection of new yeast strains for improved traits or fermentation performance is laborious, due to the allotetraploid nature of lager yeasts. Initially, we have generated new F1 hybrids by classical genetics, using spore clones of lager yeast and S. cerevisiae and complementation of auxotrophies of the single strains upon mating. These hybrids were improved on several parameters, including growth at elevated temperature and resistance against high osmolarity or high ethanol concentrations. Due to the uncertainty of chromosomal make-up of lager yeast spore clones, we introduced molecular markers to analyse mating-type composition by PCR. Based on these results, new hybrids between a lager and an ale yeast strain were isolated by micromanipulation. These hybrids were not subject to genetic modification. We generated and verified 13 hybrid strains. All of these hybrid strains showed improved stress resistance as seen in the ale parent, including improved survival at the end of fermentation. Importantly, some of the strains showed improved fermentation rates using 18° Plato at 18-25°C. Uniparental mitochondrial DNA inheritance was observed mostly from the S. cerevisiae parent. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Research on the Effects of Water Stress on Growth Traits and Water Use Efficiency of Winter Wheat

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    Sun Shuhong

    2015-01-01

    Full Text Available This research about the effects of water stress at different growth stages on the crop growth traits has a practical significance in guiding water-saving irrigation. The box test method is adopted to test the water stress of winter wheat at different stages, observe the plant height, leaf area and yield, and analyze the water use efficiency under the condition of water stress. The results show that the water stress in each growth period will play an inhibiting role in the plant height and leaf area of winter wheat; the water stress duration at a single stage is relatively short, and rehydration crop has a certain compensatory growth without making a big difference; the continuous water stress stage plays a significantly inhibiting role in the plant height and leaf area.; water stress has a largest effect on the plant height in the elongation period; the heading period suffers from water stress, so the leaf area decreases rapidly; water stress at a single stage in the appropriate period can increase water use efficiency. Regulated deficit irrigation can reduce luxury water consumption, which has a little effect on the yield and plays a guiding role in water saving and stable yield.

  19. PERK induces resistance to cell death elicited by endoplasmic reticulum stress and chemotherapy.

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    Salaroglio, Iris C; Panada, Elisa; Moiso, Enrico; Buondonno, Ilaria; Provero, Paolo; Rubinstein, Menachem; Kopecka, Joanna; Riganti, Chiara

    2017-05-12

    Nutrient deprivation, hypoxia, radiotherapy and chemotherapy induce endoplasmic reticulum (ER) stress, which activates the so-called unfolded protein response (UPR). Extensive and acute ER stress directs the UPR towards activation of death-triggering pathways. Cancer cells are selected to resist mild and prolonged ER stress by activating pro-survival UPR. We recently found that drug-resistant tumor cells are simultaneously resistant to ER stress-triggered cell death. It is not known if cancer cells adapted to ER stressing conditions acquire a chemoresistant phenotype. To investigate this issue, we generated human cancer cells clones with acquired resistance to ER stress from ER stress-sensitive and chemosensitive cells. ER stress-resistant cells were cross-resistant to multiple chemotherapeutic drugs: such multidrug resistance (MDR) was due to the overexpression of the plasma-membrane transporter MDR related protein 1 (MRP1). Gene profiling analysis unveiled that cells with acquired resistance to ER stress and chemotherapy share higher expression of the UPR sensor protein kinase RNA-like endoplasmic reticulum kinase (PERK), which mediated the erythroid-derived 2-like 2 (Nrf2)-driven transcription of MRP1. Disrupting PERK/Nrf2 axis reversed at the same time resistance to ER stress and chemotherapy. The inducible silencing of PERK reduced tumor growth and restored chemosensitivity in resistant tumor xenografts. Our work demonstrates for the first time that the adaptation to ER stress in cancer cells produces a MDR phenotype. The PERK/Nrf2/MRP1 axis is responsible for the resistance to ER stress and chemotherapy, and may represent a good therapeutic target in aggressive and resistant tumors.

  20. Clonal Plasticity of Aquatic Plant Species Submitted to Mechanical Stress: Escape versus Resistance Strategy

    Science.gov (United States)

    Puijalon, Sara; Bouma, Tjeerd J.; Van Groenendael, Jan; Bornette, Gudrun

    2008-01-01

    Background and Aims The plastic alterations of clonal architecture are likely to have functional consequences, as they affect the spatial distribution of ramets over patchy environments. However, little is known about the effect of mechanical stresses on the clonal growth. The aim of the present study was to investigate the clonal plasticity induced by mechanical stress consisting of continuous water current encountered by aquatic plants. More particularly, the aim was to test the capacity of the plants to escape this stress through clonal plastic responses. Methods The transplantation of ramets of the same clone in two contrasting flow velocity conditions was carried out for two species (Potamogeton coloratus and Mentha aquatica) which have contrasting clonal growth forms. Relative allocation to clonal growth, to creeping stems in the clonal biomass, number and total length of creeping stems, spacer length and main creeping stem direction were measured. Key Results For P. coloratus, plants exposed to water current displayed increased total length of creeping stems, increased relative allocation to creeping stems within the clonal dry mass and increased spacer length. For M. aquatica, plants exposed to current displayed increased number and total length of creeping stems. Exposure to current induced for both species a significant increase of the proportion of creeping stems in the downstream direction to the detriment of creeping stems perpendicular to flow. Conclusions This study demonstrates that mechanical stress from current flow induced plastic variation in clonal traits for both species. The responses of P. coloratus could lead to an escape strategy, with low benefits with respect to sheltering and anchorage. The responses of M. aquatica that may result in a denser canopy and enhancement of anchorage efficiency could lead to a resistance strategy. PMID:18854376

  1. Stressful life events are associated with insulin resistance among Chinese immigrant women in the United States

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    Carolyn Y. Fang

    2015-01-01

    Conclusions: This is one of the first studies to examine the associations between psychosocial stress and insulin resistance in Chinese immigrant women. These findings contribute to a growing body of literature on stress and diabetes risk in an immigrant population.

  2. Context-dependent effects of cold stress on behavioral, physiological, and life-history traits of the red flour beetle.

    Science.gov (United States)

    Scharf, Inon; Wertheimer, Keren-Or; Xin, Joy Lim; Gilad, Tomer; Goldenberg, Inna; Subach, Aziz

    2017-06-20

    Animals are exposed in nature to a variety of stressors. While stress is generally harmful, mild stress can also be beneficial and contribute to reproduction and survival. We studied the effect of five cold shock events versus a single cold shock and a control group, representing three levels of stress (harsh, mild, and no stress), on behavioral, physiological, and life-history traits of the red flour beetle (Tribolium castaneum, Herbst 1797). Beetles exposed to harsh cold stress were less active than a control group: they moved less and failed more frequently to detect a food patch. Their probability to mate was also lower. Beetle pairs exposed to harsh cold stress frequently failed to reproduce at all, and if reproducing, females laid fewer eggs, which were, as larvae in mid-development, smaller than those in the control group. However, harsh cold stress led to improved female starvation tolerance, probably due to enhanced lipid accumulation. Harsh cold shock also improved tolerance to an additional cold shock compared to the control. Finally, a single cold shock event negatively affected fewer measured response variables than the harsh cold stress, but also enhanced neither starvation tolerance nor tolerance to an additional cold shock. The consequences of a harsher cold stress are thus not solely detrimental but might even enhance survival under stressful conditions. Under benign conditions, nevertheless, harsh stress impedes beetle performance. The harsh stress probably shifted the balance point of the survival-reproduction trade-off, a shift that did not take place following exposure to mild stress. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  3. The relationship between interpersonal traits and posttraumatic stress disorder symptoms: analyses from Wenchuan earthquake adolescent survivors in China.

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    Xia, Ling-Xiang; Ding, Cody

    2011-08-01

    This study explores the relationship between interpersonal traits and posttraumatic stress disorder (PTSD) symptoms in a sample of 617 middle and high school students 16 months after the Wenchuan earthquake in China using the Impact of Event Scale-Revised (IES-R) and the Interpersonal Self-Supporting Scale (ISSS). Even when the effects of gender and grade level were controlled for, the results from regression analyses revealed that greater interpersonal independence, interpersonal initiative, interpersonal responsibility, and interpersonal openness are associated with lesser PTSD symptoms 16 months later. Copyright © 2011 International Society for Traumatic Stress Studies.

  4. Effects of Cold and Heat Stress on Egg Quality Traits of a Newly Developed Native Hybrid Layer

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    İsmail Durmuş

    2015-03-01

    Full Text Available ATAK-S is a newly developed native hybrid layer. Although the laying performance of this hybrid has been studied and determined, the performance response of the hybrid to different environmental temperature conditions is not known. This study was therefore undertaken to determine the effect of cold and heat stress on egg quality traits. Hens were divided into three different groups; control (20°C, low (12°C and high (32°C. A total of 360 hens, with 120 in each of the groups, were used in the study. Hens were held in three tier battery cages in an environmentally controlled poultry house. The study lasted for 3 weeks. No differences were found among different groups in terms of shape index, albumen height and Haugh unit of the egg quality traits. It was found that the differences among the heat groups in terms of egg shell breaking strength, egg weight, shell thickness and yolk colour were significant and the value of these traits decreased under the heat stress conditions, whereas they were not affected from the cold stress.

  5. Affective and neuroendocrine stress reactivity to an academic examination: influence of the 5-HTTLPR genotype and trait neuroticism.

    Science.gov (United States)

    Verschoor, Ellen; Markus, C Rob

    2011-07-01

    The current study examined the singular and interactive effects of the 5-HTTLPR genotype and trait neuroticism on affective and physiological stress responses to an academic examination in healthy undergraduate students. From 771 students, 46 short/short (S/S)-allele carriers and 48 long/long (L/L)-allele carriers with the lowest and the highest neuroticism scores (80 females, 14 males; mean age±SD: 20.3±1.7 years) were selected. Salivary cortisol concentrations, mood and perceived stress were assessed before and after a 2-h written examination and compared with a control day. Negative mood, perceived stress and cortisol significantly increased during the examination compared to the control day. Negative stress effects on mood and perceived stress were significantly larger for S/S-allele carriers compared to L/L-allele carriers, regardless of trait neuroticism. Since vulnerability to real-life stressors is an important risk factor for depression pathogenesis, this may be a mediating factor making S/S-allele carriers more susceptible for depression symptoms. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Quantitative trait loci meta-analysis of Plum pox virus resistance in apricot (Prunus armeniaca L.): new insights on the organization and the identification of genomic resistance factors.

    Science.gov (United States)

    Marandel, Grégoire; Salava, Jaroslav; Abbott, Albert; Candresse, Thierry; Decroocq, Véronique

    2009-05-01

    Plum pox virus (PPV) is responsible for sharka disease, one of the most detrimental stone fruit diseases affecting Prunus trees worldwide. Only a few apricot cultivars have been described as resistant, most originating from North American breeding programmes. Several PPV resistance quantitative trait loci (QTLs) have been mapped in various progenies, consistently highlighting the contribution to the resistance of the upper part of linkage group 1 (LG1). However, to date, no consensus has been reached on the precise number of QTLs linked to the resistance to PPV in apricot and P. davidiana or on their accurate position on the genetic linkage map. In the present study, the quantitative resistance of cultivar 'Harlayne' was analysed over five growth periods in a large F1 population. Four QTLs were identified, three mapping on LG1, explaining between 5% and 39% of the observed phenotypic variance. In an effort to further this analysis of PPV resistance in apricot, these results were merged in a single QTL meta-analysis with those of five other PPV resistance analyses available in the literature. Three consensus QTL regions were identified on LG1 and a putative fourth region on LG3. QTL meta-analysis also revealed the contribution of each resistant cultivar to metaQTLs, providing interesting comparative data on the resistance factors shared between the resistance sources used in the various studies. Finally, it was shown that one of the metaQTLs co-localizes with the eukaryotic translation initiation factor eIF4E, thus providing new hypotheses on the mechanisms of PPV resistance in apricot.

  7. Resistance to powdery mildew in Spanish barley landraces is controlled by different sets of quantitative trait loci.

    Science.gov (United States)

    Silvar, C; Casas, A M; Igartua, E; Ponce-Molina, L J; Gracia, M P; Schweizer, G; Herz, M; Flath, K; Waugh, R; Kopahnke, D; Ordon, F

    2011-10-01

    Twenty-two landrace-derived inbred lines from the Spanish Barley Core Collection (SBCC) were found to display high levels of resistance to a panel of 27 isolates of the fungus Blumeria graminis that exhibit a wide variety of virulences. Among these lines, SBCC145 showed high overall resistance and a distinctive spectrum of resistance compared with the other lines. Against this background, the main goal of the present work was to investigate the genetic basis underlying such resistance using a doubled haploid population derived from a cross between SBCC145 and the elite spring cultivar Beatrix. The population was genotyped with the 1,536-SNP Illumina GoldenGate Oligonucleotide Pool Assay (Barley OPA-1 or BOPA1 for short), whereas phenotypic analysis was performed using two B. graminis isolates. A major quantitative trait locus (QTL) for resistance to both isolates was identified on the long arm of chromosome 6H (6HL) and accounted for ca. 60% of the phenotypic variance. Depending on the B. graminis isolate tested, three other minor QTLs were detected on chromosomes 2H and 7H, which explained less than 5% of the phenotypic variation each. In all cases, the alleles for resistance derived from the Spanish parent SBCC145. The position, the magnitude of the effect observed and the proportion of phenotypic variation accounted for by the QTL on 6HL suggest this is a newly identified locus for broad-based resistance to powdery mildew.

  8. Callous-unemotional traits and early life stress predict treatment effects on stress and sex hormone functioning in incarcerated male adolescents.

    Science.gov (United States)

    Johnson, Megan; Vitacco, Michael J; Shirtcliff, Elizabeth A

    2017-12-18

    The stress response system is highly plastic, and hormone rhythms may "adaptively calibrate" in response to treatment. This investigation assessed whether stress and sex hormone diurnal rhythms changed over the course of behavioral treatment, and whether callous-unemotional (CU) traits and history of early adversity affected treatment results on diurnal hormone functioning in a sample of 28 incarcerated adolescent males. It was hypothesized that the treatment would have beneficial effects, such that healthier diurnal rhythms would emerge post-treatment. Diurnal cortisol, testosterone, and dehydroepiandrosterone (DHEA) were sampled two weeks after admission to the correctional/treatment facility, and again approximately four months later. Positive treatment effects were detected for the whole sample, such that testosterone dampened across treatment. CU traits predicted a non-optimal hormone response to treatment, potentially indicating biological preparedness to respond to acts of social dominance and aggression. The interaction between CU traits and adversity predicted a promising and sensitized response to treatment including increased cortisol and a steeper testosterone drop across treatment. Results suggest that stress and sex hormones are highly receptive to treatment during this window of development.

  9. Trait impulsive choice predicts resistance to extinction and propensity to relapse to cocaine seeking: a bidirectional investigation.

    Science.gov (United States)

    Broos, Nienke; Diergaarde, Leontien; Schoffelmeer, Anton Nm; Pattij, Tommy; De Vries, Taco J

    2012-05-01

    Despite the strong association between impulsivity and addiction in humans, it is still a matter of debate whether impulsive choice predisposes to, or results from, drug dependence. Furthermore, it is unknown whether treating impulsivity can protect against relapse propensity. Therefore, this study explored the bidirectional relationship between impulsive choice and cocaine taking and seeking in rat behavioral models. In experiment 1, to determine whether impulsive choice predisposes to cocaine taking or seeking, rats were selected based on trait impulsivity in a delayed reward task and subsequently compared on various stages of cocaine self-administration (SA). To examine the consequence of cocaine intake on impulsive choice, impulsivity was monitored once a week throughout various stages of cocaine SA. To determine whether treating impulsive choice can protect against relapse propensity, in experiment 2, impulsive choice was manipulated by pharmacological interventions and cocaine-associated contextual cues. Trait impulsive choice as determined in experiment 1 predicted high extinction resistance and enhanced propensity to context-induced relapse in the cocaine SA model, whereas cocaine intake did not alter impulsive choice. Furthermore, acute changes in impulsive choice were not related to rates of context-induced relapse. Taken together, the current data indicate that trait impulsive choice predicts persistent cocaine seeking during extinction and enhanced propensity to relapse, whereas acute manipulations of impulsive choice had no favorable outcomes on relapse measures. These observations suggest that trait impulsivity can be used as a predictive factor for addiction liability, but treating this impulsivity does not necessarily protect against relapse.

  10. Trait Impulsive Choice Predicts Resistance to Extinction and Propensity to Relapse to Cocaine Seeking: A Bidirectional Investigation

    Science.gov (United States)

    Broos, Nienke; Diergaarde, Leontien; Schoffelmeer, Anton NM; Pattij, Tommy; De Vries, Taco J

    2012-01-01

    Despite the strong association between impulsivity and addiction in humans, it is still a matter of debate whether impulsive choice predisposes to, or results from, drug dependence. Furthermore, it is unknown whether treating impulsivity can protect against relapse propensity. Therefore, this study explored the bidirectional relationship between impulsive choice and cocaine taking and seeking in rat behavioral models. In experiment 1, to determine whether impulsive choice predisposes to cocaine taking or seeking, rats were selected based on trait impulsivity in a delayed reward task and subsequently compared on various stages of cocaine self-administration (SA). To examine the consequence of cocaine intake on impulsive choice, impulsivity was monitored once a week throughout various stages of cocaine SA. To determine whether treating impulsive choice can protect against relapse propensity, in experiment 2, impulsive choice was manipulated by pharmacological interventions and cocaine-associated contextual cues. Trait impulsive choice as determined in experiment 1 predicted high extinction resistance and enhanced propensity to context-induced relapse in the cocaine SA model, whereas cocaine intake did not alter impulsive choice. Furthermore, acute changes in impulsive choice were not related to rates of context-induced relapse. Taken together, the current data indicate that trait impulsive choice predicts persistent cocaine seeking during extinction and enhanced propensity to relapse, whereas acute manipulations of impulsive choice had no favorable outcomes on relapse measures. These observations suggest that trait impulsivity can be used as a predictive factor for addiction liability, but treating this impulsivity does not necessarily protect against relapse. PMID:22318198

  11. Anatomical traits related to stress in high density populations of Typha angustifolia L. (Typhaceae

    Directory of Open Access Journals (Sweden)

    F. F. Corrêa

    Full Text Available Abstract Some macrophytes species show a high growth potential, colonizing large areas on aquatic environments. Cattail (Typha angustifolia L. uncontrolled growth causes several problems to human activities and local biodiversity, but this also may lead to competition and further problems for this species itself. Thus, the objective of this study was to investigate anatomical modifications on T. angustifolia plants from different population densities, once it can help to understand its biology. Roots and leaves were collected from natural populations growing under high and low densities. These plant materials were fixed and submitted to usual plant microtechnique procedures. Slides were observed and photographed under light microscopy and images were analyzed in the UTHSCSA-Imagetool software. The experimental design was completely randomized with two treatments and ten replicates, data were submitted to one-way ANOVA and Scott-Knott test at p<0.05. Leaves from low density populations showed higher stomatal density and index. These modifications on stomatal characteristics were more evident on the leaf abaxial surface. Plants from low density populations showed thicker mesophyll and higher proportion of aerenchymal area. Roots from low density populations showed a higher proportion of the vascular cylinder. Whereas, plants from higher density populations showed greater thickness of the endodermis, exodermis, phloem and root cortex. Higher density populations showed a higher proportion of aerenchymal gaps in the root cortex. Therefore, cattail plants from populations growing under high density population show anatomical traits typical of plants under stress, which promotes the development of less functional anatomical modifications to aquatic environments.

  12. Sexual conflict and correlated evolution between male persistence and female resistance traits in the seed beetle Callosobruchus maculatus.

    Science.gov (United States)

    Dougherty, Liam R; van Lieshout, Emile; McNamara, Kathryn B; Moschilla, Joe A; Arnqvist, Göran; Simmons, Leigh W

    2017-05-31

    Traumatic mating (or copulatory wounding) is an extreme form of sexual conflict whereby male genitalia physically harm females during mating. In such species females are expected to evolve counter-adaptations to reduce male-induced harm. Importantly, female counter-adaptations may include both genital and non-genital traits. In this study, we examine evolutionary associations between harmful male genital morphology and female reproductive tract morphology and immune function across 13 populations of the seed beetle Callosobruchus maculatus We detected positive correlated evolution between the injuriousness of male genitalia and putative female resistance adaptations across populations. Moreover, we found evidence for a negative relationship between female immunity and population productivity, which suggests that investment in female resistance may be costly due to the resource trade-offs that are predicted between immunity and reproduction. Finally, the degree of female tract scarring (harm to females) was greater in those populations with both longer aedeagal spines and a thinner female tract lining. Our results are thus consistent with a sexual arms race, which is only apparent when both male and female traits are taken into account. Importantly, our study provides rare evidence for sexually antagonistic coevolution of male and female traits at the within-species level. © 2017 The Author(s).

  13. Association between the Five Factor personality traits and perceived stress: is the effect mediated by general self-efficacy?

    Science.gov (United States)

    Ebstrup, Jeanette Frost; Eplov, Lene Falgaard; Pisinger, Charlotta; Jørgensen, Torben

    2011-07-01

    Ill-health resulting from chronic stress is influenced by personality traits leading to different ways of appraising and coping with life's daily hassles. Using a large population sample the study aimed to investigate possible associations between perceived stress and the personality dimensions of neuroticism, extroversion, openness, agreeableness, and conscientiousness, and to explore the role of general self-efficacy (GSE). A population-based cross-sectional study was conducted at the Research Centre for Prevention and Health, Denmark, in 2006-2008. Men and women (N=3471) aged 18-69, were randomly sampled in the suburbs of Copenhagen. We used the NEO Five-Factor Inventory (NEO-FFI), Cohen's Perceived Stress Scale and the General Self-Efficacy Scale. Negative associations were found between perceived stress and extroversion, conscientiousness, agreeableness, and openness - the latter initially non-significant - whilst neuroticism had a positive association. The associations with agreeableness and openness became positive and significant, respectively, when GSE was included. All five personality-stress models were mediated by GSE, with extroversion and conscientiousness having the strongest mediating effect. The strongest stress-association was found for neuroticism. GSE was shown to change the impact and interpretation of the personality dimensions on perceived stress. These results indicate that GSE is an important factor to consider in the link between personality and perceived stress.

  14. Resistant Traits in Digital Organisms Do Not Revert Preselection Status despite Extended Deselection: Implications to Microbial Antibiotics Resistance

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    Clarence F. G. Castillo

    2014-01-01

    Full Text Available Antibiotics resistance is a serious biomedical issue as formally susceptible organisms gain resistance under its selective pressure. There have been contradictory results regarding the prevalence of resistance following withdrawal and disuse of the specific antibiotics. Here, we use experimental evolution in “digital organisms” to examine the rate of gain and loss of resistance under the assumption that there is no fitness cost for maintaining resistance. Our results show that selective pressure is likely to result in maximum resistance with respect to the selective pressure. During deselection as a result of disuse of the specific antibiotics, a large initial loss and prolonged stabilization of resistance are observed, but resistance is not lost to the stage of preselection. This suggests that a pool of partial persists organisms persist long after withdrawal of selective pressure at a relatively constant proportion. Hence, contradictory results regarding the prevalence of resistance following withdrawal and disuse of the specific antibiotics may be a statistical variation about constant proportion. Our results also show that subsequent reintroduction of the same selective pressure results in rapid regain of maximal resistance. Thus, our simulation results suggest that complete elimination of specific antibiotics resistance is unlikely after the disuse of antibiotics once a resistant pool of microorganisms has been established.

  15. Resistant traits in digital organisms do not revert preselection status despite extended deselection: implications to microbial antibiotics resistance.

    Science.gov (United States)

    Castillo, Clarence F G; Ling, Maurice H T

    2014-01-01

    Antibiotics resistance is a serious biomedical issue as formally susceptible organisms gain resistance under its selective pressure. There have been contradictory results regarding the prevalence of resistance following withdrawal and disuse of the specific antibiotics. Here, we use experimental evolution in "digital organisms" to examine the rate of gain and loss of resistance under the assumption that there is no fitness cost for maintaining resistance. Our results show that selective pressure is likely to result in maximum resistance with respect to the selective pressure. During deselection as a result of disuse of the specific antibiotics, a large initial loss and prolonged stabilization of resistance are observed, but resistance is not lost to the stage of preselection. This suggests that a pool of partial persists organisms persist long after withdrawal of selective pressure at a relatively constant proportion. Hence, contradictory results regarding the prevalence of resistance following withdrawal and disuse of the specific antibiotics may be a statistical variation about constant proportion. Our results also show that subsequent reintroduction of the same selective pressure results in rapid regain of maximal resistance. Thus, our simulation results suggest that complete elimination of specific antibiotics resistance is unlikely after the disuse of antibiotics once a resistant pool of microorganisms has been established.

  16. Mathematical quantification of the induced stress resistance of microbial populations during non-isothermal stresses.

    Science.gov (United States)

    Garre, Alberto; Huertas, Juan Pablo; González-Tejedor, Gerardo A; Fernández, Pablo S; Egea, Jose A; Palop, Alfredo; Esnoz, Arturo

    2018-02-02

    This contribution presents a mathematical model to describe non-isothermal microbial inactivation processes taking into account the acclimation of the microbial cell to thermal stress. The model extends the log-linear inactivation model including a variable and model parameters quantifying the induced thermal resistance. The model has been tested on cells of Escherichia coli against two families of non-isothermal profiles with different constant heating rates. One of the families was composed of monophasic profiles, consisting of a non-isothermal heating stage from 35 to 70°C; the other family was composed of biphasic profiles, consisting of a non-isothermal heating stage followed by a holding period at constant temperature of 57.5°C. Lower heating rates resulted in a higher thermal resistance of the bacterial population. This was reflected in a higher D-value. The parameter estimation was performed in two steps. Firstly, the D and z-values were estimated from the isothermal experiments. Next, the parameters describing the acclimation were estimated using one of the biphasic profiles. This set of parameters was able to describe the remaining experimental data. Finally, a methodology for the construction of diagrams illustrating the magnitude of the induced thermal resistance is presented. The methodology has been illustrated by building it for a biphasic temperature profile with a linear heating phase and a holding phase. This diagram provides a visualization of how the shape of the temperature profile (heating rate and holding temperature) affects the acclimation of the cell to the thermal stress. This diagram can be used for the design of inactivation treatments by industry taking into account the acclimation of the cell to the thermal stress. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The expression of pre- and postcopulatory sexually selected traits reflects levels of dietary stress in guppies.

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    Md Moshiur Rahman

    Full Text Available Environmental and ecological conditions can shape the evolution of life history traits in many animals. Among such factors, food or nutrition availability can play an important evolutionary role in moderating an animal's life history traits, particularly sexually selected traits. Here, we test whether diet quantity and/or composition in the form of omega-3 long chain polyunsaturated fatty acids (here termed 'n3LC' influence the expression of pre- and postcopulatory traits in the guppy (Poecilia reticulata, a livebearing poeciliid fish. We assigned males haphazardly to one of two experimental diets supplemented with n3LC, and each of these diet treatments was further divided into two diet 'quantity' treatments. Our experimental design therefore explored the main and interacting effects of two factors (n3LC content and diet quantity on the expression of precopulatory (sexual behaviour and sexual ornamentation, including the size, number and spectral properties of colour spots and postcopulatory (the velocity, viability, number and length of sperm sexually selected traits. Our study revealed that diet quantity had significant effects on most of the pre- and postcopulatory traits, while n3LC manipulation had a significant effect on sperm traits and in particular on sperm viability. Our analyses also revealed interacting effects of diet quantity and n3LC levels on courtship displays, and the area of orange and iridescent colour spots in the males' colour patterns. We also confirmed that our dietary manipulations of n3LC resulted in the differential uptake of n3LC in body and testes tissues in the different n3LC groups. This study reveals the effects of diet quantity and n3LC on behavioural, ornamental and ejaculate traits in P. reticulata and underscores the likely role that diet plays in maintaining the high variability in these condition-dependent sexual traits.

  18. Nutritional Stress Causes Heterogeneous Relationships with Multi-Trait FA in Lesser Black-Backed Gull Chicks: An Aviary Experiment

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    Trisha Gupta

    2016-11-01

    Full Text Available Environmental stressors have the potential to induce perturbations in the development of young individuals, leading to aberrant and unstable development. This may manifest as fluctuating asymmetry (FA; small, non-directional changes in the bilateral symmetry of morphological traits. Although widely regarded as a proxy for stress effects, the use of FA as a biomarker is still a topic of much debate. We investigated the applicability of FA as an indicator of nutritional stress (brought about by energetic constraints by experimental manipulation of the diet composition and quantity during the growth of Lesser Black-backed Gull (Larus fuscus chicks. FA as an endpoint was measured across the tarsus, wing and 10th primary feather when chicks reached 30 days of age. Although levels of asymmetry were found to increase with stress in the feather, relationships with tarsus and wing FA were mixed and mostly non-significant. Furthermore, we did not find any correlations in unsigned FA between traits, indicating the absence of organism-wide asymmetry. Our study was therefore unable to find unequivocal evidence in support of the application of FA as a reliable estimator of nutritional stress.

  19. The influence of androstadienone during psychosocial stress is modulated by gender, trait anxiety and subjective stress: An fMRI study.

    Science.gov (United States)

    Chung, K C; Springer, I; Kogler, L; Turetsky, B; Freiherr, J; Derntl, B

    2016-06-01

    Androstadienone (ANDR), a bodily secreted steroid compound, is a socially relevant chemosignal that modulates subjective and (neuro)physiological responses, predominantly in females. The impact of ANDR on stress responses in males and females has not been explored. Therefore, this fMRI study aimed to examine psychosocial stress reactions induced by mental arithmetic and social evaluation on behavioral and hormonal levels (46 participants: 15 naturally cycling females in their early follicular phase (EF), 15 females on hormonal contraceptives (HC) and 16 males); and on a neural level (40 participants: 13 EF-females, 13 HC-females and 14 males) in an ANDR and placebo treatment repeated-measures design. While no gender differences emerged in subjective ratings and performance during stress, neural activation patterns differed significantly. Besides, ANDR attenuated the post-stress increase of negative mood in all participants. Region of interest analyses showed that irrespective of treatment, males showed stronger activation of the dorsolateral prefrontal cortex (DLPFC) than females. At the whole brain level, gender differences emerged indicating stronger fronto-parietal activation in males compared to HC-females on both treatments. Males showed stronger visual and fusiform activation than EF-females under ANDR. Both female groups did not show stronger activation than males. Further, error ratio in the ANDR-stress condition was positively associated with their post-stress cortisol level and increase in subjective stress in males; and male DLPFC activity in the ANDR-stress condition was negatively associated with trait anxiety. Surprisingly, compared to HC-females, EF-female only showed stronger activation of arousal-related areas under placebo treatment. Taken together, these findings suggest that the male stress reaction under social evaluative threat was stronger than female stress reactions as a function of ANDR. More specifically, this effect on behavioral and

  20. [Advances in molecular mechanisms of bacterial resistance caused by stress-induced transfer of resistance genes--a review].

    Science.gov (United States)

    Sun, Dongchang; Wang, Bing; Zhu, Lihong

    2013-07-04

    The transfer of resistance gene is one of the most important causes of bacterial resistance. Recent studies reveal that stresses induce the transfer of antibiotic resistance gene through multiple mechanisms. DNA damage stresses trigger bacterial SOS response and induce the transfer of resistance gene mediated by conjugative DNA. Antibiotic stresses induce natural bacterial competence for transformation in some bacteria which lack the SOS system. In addition, our latest studies show that the general stress response regulator RpoS regulates a novel type of resistance gene transfer which is mediated by double-stranded plasmid DNA and occurs exclusively on the solid surface. In this review, we summarized recent advances in SOS dependent and independent stress-induced DNA transfer which is mediated by conjugation and transformation respectively, and the transfer of double-stranded plasmid DNA on the solid surface which is regulated by RpoS. We propose that future work should address how stresses activate the key regulators and how these regulators control the expression of gene transfer related genes. Answers to the above questions would pave the way for searching for candidate targets for controlling bacterial resistance resulted from the transfer of antibiotic genes.

  1. [The regulatory-adaptive status in the evaluation of human stress-resistance].

    Science.gov (United States)

    Pokrovskiĭ, V M; Mingalev, A N

    2012-01-01

    There was offered a method of human stress-resistance evaluation via the dynamics of the regulatory-adaptive status. The regulatory-adaptive status was being determined via the parameters of the cardiorespiratory synchronism in the original state and at the application of the stress factor. Individuals, whose regulatory-adaptive status didn't change or decreased by not more than 5-6% at the exposition to the stress factor formed the group with a high level of stress-resistance. The individuals, whose regulatory adaptive status at the exposition to the stress factor decreased by less than 50% formed a group with a moderate level of stress-resistance. The examinees, whose regulatory-adaptive status decreased by more than 50% in a response to the stress factor were set in a group with a low stress-resistance level. The method was tested in the three stress models: 1) exam stress-on 58 students; 2) parachute jump stress-on 35 beginner parachutists; 3) stress, caused by the relocation to the zone of the catastrophe on 30 rescuers. In all the three models the method is highly informative. At the same time the levels of the stress-resistance were being evaluated by the psychological methods. It was shown, that the evaluation of the stress-resistance level via the dynamics of the regulatory-adaptive status allows to objectively characterize the ability of an individual to resist stress and should be included in the test complex for the casting of the candidates for the extreme professions.

  2. Carcass and meat quality traits of chickens fed diets concurrently supplemented with vitamins C and E under constant heat stress.

    Science.gov (United States)

    Zeferino, C P; Komiyama, C M; Pelícia, V C; Fascina, V B; Aoyagi, M M; Coutinho, L L; Sartori, J R; Moura, A S A M T

    2016-01-01

    The objective of this study was to determine if a diet supplemented simultaneously with vitamins C and E would alleviate the negative effects of heat stress, applied between 28 and 42 days of age, on performance, carcass and meat quality traits of broiler chickens. A total of 384 male broiler chickens were assigned to a completely randomized design, with a 2×3 factorial arrangement (diet with or without vitamin supplementation and two ambient temperatures plus a pair-feeding group) and 16 replicates. Chickens were kept in thermoneutral conditions up to 28 days of age. They were then housed in groups of four per cage, in three environmentally controlled chambers: two thermoneutral (22.5 and 22.6°C) and one for heat stress (32°C). Half the chickens were fed a diet supplemented with vitamins C (257 to 288 mg/kg) and E (93 to 109 mg/kg). In the thermoneutral chambers, half of the chickens were pair-fed to heat stressed chickens, receiving each day the average feed intake recorded in the heat stress chamber in the previous day. Meat physical quality analyses were performed on the pectoralis major muscle. No ambient temperature×diet supplementation interaction effects were detected on performance, carcass, or meat quality traits. The supplemented diet resulted in lower growth performance, attributed either to a carry-over effect of the lower initial BW, or to a possible catabolic effect of vitamins C and E when supplemented simultaneously at high levels. Heat stress reduced slaughter and carcass weights, average daily gain and feed intake, and increased feed conversion. Growth performance of pair-fed chickens was similar to that of heat stressed chickens. Exposure to heat stress increased carcass and abdominal fat percentages, but reduced breast, liver and heart percentages. Pair-fed chickens showed the lowest fat percentage and their breast percentage was similar to controls. Heat stress increased meat pH and negatively affected meat color and cooking loss. In pair

  3. Early resistance change and stress/electromigration evolution in near bamboo interconnects

    NARCIS (Netherlands)

    Petrescu, V.; Mouthaan, A.J.; Dima, G.; Govoreanu, B.; Mitrea, O.; Profirescu, M.

    1997-01-01

    A complete description for early resistance change and mechanical stress evolution in near-bamboo interconnects, related to the electromigration, is given in this paper. The proposed model, for the first time, combines the stress/vacancy concentration evolution with the early resistance change of

  4. Mechanisms of Stress Resistance and Gene Regulation in the Radioresistant Bacterium Deinococcus radiodurans.

    Science.gov (United States)

    Agapov, A A; Kulbachinskiy, A V

    2015-10-01

    The bacterium Deinococcus radiodurans reveals extraordinary resistance to ionizing radiation, oxidative stress, desiccation, and other damaging conditions. In this review, we consider the main molecular mechanisms underlying such resistance, including the action of specific DNA repair and antioxidation systems, and transcription regulation during the anti-stress response.

  5. Ordovas-Oxidized LDL is associated with metabolic syndrome traits independently of central obesity and insulin resistance

    Science.gov (United States)

    This study assesses whether oxidative stress, using oxidized LDL (ox-LDL) as a proxy, is associated with metabolic syndrome (MS), whether ox-LDL mediates the association between central obesity and MS, and whether insulin resistance mediates the association between ox-LDL and MS. We examined baselin...

  6. Nuclear Receptors Resolve Endoplasmic Reticulum Stress to Improve Hepatic Insulin Resistance

    Science.gov (United States)

    2017-01-01

    Chronic endoplasmic reticulum (ER) stress culminating in proteotoxicity contributes to the development of insulin resistance and progression to type 2 diabetes mellitus. Pharmacologic interventions targeting several different nuclear receptors have emerged as potential treatments for insulin resistance. The mechanistic basis for these antidiabetic effects has primarily been attributed to multiple metabolic and inflammatory functions. Here we review recent advances in our understanding of the association of ER stress with insulin resistance and the role of nuclear receptors in promoting ER stress resolution and improving insulin resistance in the liver. PMID:28236381

  7. Identification of quantitative trait loci conditioning partial resistance to Phytophthora sojae in soybean PI 407861A

    Science.gov (United States)

    Improving resistance for Phytophthora root and stem rot is an important goal in soybean [Glycine max (L.) Merr.] breeding. Partial resistance can be as effective in managing this disease as single-gene (Rps) mediated resistance and is more durable. The objective of this study was to identify QTL con...

  8. The Effects of Drought Stress and Humic Acid on Morphological Traits, Yield and Anthocyanin of Roselle (Hibiscus sabdariffa L.

    Directory of Open Access Journals (Sweden)

    mojgan sanjarimijani

    2017-01-01

    Full Text Available Introduction Roselle (Hibiscus sabdariffa L. as a medicinal plant belongs to the Malvacea family. Their active ingredient increases under water stress. Humic acid bacteria derived from humus and other natural resources have hormonal effects and can improve nutrient absorption to enhance performance especially under stress conditions . Materials and methods This experiment was conducted in the research of agricultural education centre Jiroft in 2013. Field experiment was carried out as split plot design with three replications. Water deficit stress set as main factor with three levels (A1= Irrigation after 50, A2= 100 and A3= 150 mm evaporation from pan class A and humic acid was in four manners (B1= non humic acid, B2= once with Irrigation, B3= once with Irrigation + Once spraying, B4= once with Irrigation + twice Spraying. Humic acid was used to form Irrigation spray in order to arrange with compactness (10 kg.ha-1, (250 ml/100L. In late September, which coincides with the end of the heading, plant height, inflorescence length, number of branches, stem diameter, fresh and dry weight of plant, fresh and dry weight of sepals, were examined. Wagner method was used to measure anthocyanin content sepals (Wagner, 1979. Finally, data was analyzed using SAS 9.1 and means were compared by Duncan’s multiple range test at 5% level of probability. Results and discussion The analysis of variance showed that drought stress and humic acid had significant effect on growth parameters, vegetative and generative yield and anthocyanin. Drought stress decreased plant height, inflorescence length, stem diameterand fresh and dry weight sepals. The highest values of these traits was obtained in the first level of stress (50 mm evaporation from pan class A. Due to the reduction in mentioned properties, reducing the pressure tolerance and the subsequent reduction in drought conditions was considered as division and cell enlargement. The reduction in growth parameters

  9. Personality traits of the Five-Factor Model are associated with work-related stress in special force police officers.

    Science.gov (United States)

    Garbarino, S; Chiorri, C; Magnavita, N

    2014-04-01

    The police work is particularly stressful. The aim of this work was to clarify whether the personality factors are associated with perceived stress levels or reactivity to environmental stressors in a special body of police. The police officers in charge of guaranteeing public order at the L'Aquila G8 meeting were subjected to a control of their levels of work-related stress in anticipation of the event. Personality was assessed by the Italian version of the Five-Factor Model questionnaire, while stress was measured three times (during routine work in January 2009, preparation and imminence of the event, in April and July 2009, respectively) with the demand/control/support model of Karasek and the effort/reward imbalance model of Siegrist. A total of 289 of 294 officers took part in the survey. Some personality traits of the Five-Factor Model were associated with stress levels and stress reactivity. Neuroticism (low emotional stability) showed the strongest associations with job strain (demand/control ratio) (β = 0.115, p factors may mitigate or increase the strain induced by environmental stressors.

  10. Oxidative stress and antioxidant responses to progressive resistance exercise intensity in trained and untrained males

    OpenAIRE

    H Çakır-Atabek; F. Özdemir; Çolak, R.

    2015-01-01

    The relationship between oxidative stress and some exercise components of resistance exercise (e.g. intensity, exercise volume) has not been clearly defined. Additionally, the oxidative stress markers may respond differently in various conditions. This study aims to determine the effects of progressive intensity of resistance exercise (RE) on oxidative stress and antioxidants in trained and untrained men, and also to investigate the possible threshold intensity required to evoke oxidative str...

  11. Selection on crop-derived traits and QTL in sunflower (Helianthus annuus) crop-wild hybrids under water stress.

    Science.gov (United States)

    Owart, Birkin R; Corbi, Jonathan; Burke, John M; Dechaine, Jennifer M

    2014-01-01

    Locally relevant conditions, such as water stress in irrigated agricultural regions, should be considered when assessing the risk of crop allele introgression into wild populations following hybridization. Although research in cultivars has suggested that domestication traits may reduce fecundity under water stress as compared to wild-like phenotypes, this has not been investigated in crop-wild hybrids. In this study, we examine phenotypic selection acting on, as well as the genetic architecture of vegetative, reproductive, and physiological characteristics in an experimental population of sunflower crop-wild hybrids grown under wild-like low water conditions. Crop-derived petiole length and head diameter were favored in low and control water environments. The direction of selection differed between environments for leaf size and leaf pressure potential. Interestingly, the additive effect of the crop-derived allele was in the direction favored by selection for approximately half the QTL detected in the low water environment. Selection favoring crop-derived traits and alleles in the low water environment suggests that a subset of these alleles would be likely to spread into wild populations under water stress. Furthermore, differences in selection between environments support the view that risk assessments should be conducted under multiple locally relevant conditions.

  12. Stress-related eating, obesity and associated behavioural traits in adolescents: a prospective population-based cohort study

    Science.gov (United States)

    2014-01-01

    Background Stress-related eating is associated with unhealthy eating and drinking habits and an increased risk of obesity among adults, but less is known about factors related to stress-driven eating behaviour among children and adolescents. We studied the prevalence of stress-related eating and its association with overweight, obesity, abdominal obesity, dietary and other health behaviours at the age of 16. Furthermore, we examined whether stress-related eating is predicted by early-life factors including birth size and maternal gestational health. Methods The study population comprised 3598 girls and 3347 boys from the Northern Finland Birth Cohort 1986 (NFBC1986). Followed up since their antenatal period, adolescents underwent a clinical examination, and their stress-related eating behaviour, dietary habits and other health behaviours were assessed using a postal questionnaire. We examined associations using cross-tabulations followed by latent class analysis and logistic regression to profile the adolescents and explain the risk of obesity with behavioural traits. Results Stress-related eating behaviour was more common among girls (43%) than among boys (15%). Compared with non-stress-driven eaters, stress-driven eaters had a higher prevalence of overweight, obesity and abdominal obesity. We found no significant associations between stress-eating and early-life factors. Among girls, tobacco use, shorter sleep, infrequent family meals and frequent consumption of chocolate, sweets, light sodas and alcohol were more prevalent among stress-driven eaters. Among boys, the proportions of those with frequent consumption of sausages, chocolate, sweets, hamburgers and pizza were greater among stress-driven eaters. For both genders, the proportions of those bingeing and using heavy exercise and strict diet for weight control were higher among stress-eaters. Besides a ‘healthy lifestyle’ cluster, latent class analysis revealed two other patterns (‘adverse habits’,

  13. Stress-related eating, obesity and associated behavioural traits in adolescents: a prospective population-based cohort study.

    Science.gov (United States)

    Jääskeläinen, Anne; Nevanperä, Nina; Remes, Jouko; Rahkonen, Fanni; Järvelin, Marjo-Riitta; Laitinen, Jaana

    2014-04-07

    Stress-related eating is associated with unhealthy eating and drinking habits and an increased risk of obesity among adults, but less is known about factors related to stress-driven eating behaviour among children and adolescents. We studied the prevalence of stress-related eating and its association with overweight, obesity, abdominal obesity, dietary and other health behaviours at the age of 16. Furthermore, we examined whether stress-related eating is predicted by early-life factors including birth size and maternal gestational health. The study population comprised 3598 girls and 3347 boys from the Northern Finland Birth Cohort 1986 (NFBC1986). Followed up since their antenatal period, adolescents underwent a clinical examination, and their stress-related eating behaviour, dietary habits and other health behaviours were assessed using a postal questionnaire. We examined associations using cross-tabulations followed by latent class analysis and logistic regression to profile the adolescents and explain the risk of obesity with behavioural traits. Stress-related eating behaviour was more common among girls (43%) than among boys (15%). Compared with non-stress-driven eaters, stress-driven eaters had a higher prevalence of overweight, obesity and abdominal obesity. We found no significant associations between stress-eating and early-life factors. Among girls, tobacco use, shorter sleep, infrequent family meals and frequent consumption of chocolate, sweets, light sodas and alcohol were more prevalent among stress-driven eaters. Among boys, the proportions of those with frequent consumption of sausages, chocolate, sweets, hamburgers and pizza were greater among stress-driven eaters. For both genders, the proportions of those bingeing and using heavy exercise and strict diet for weight control were higher among stress-eaters. Besides a 'healthy lifestyle' cluster, latent class analysis revealed two other patterns ('adverse habits', 'unbalanced weight control') that

  14. Detection of a quantitative trait locus associated with resistance to Ascaris suum infection in pigs.

    Science.gov (United States)

    Skallerup, Per; Nejsum, Peter; Jørgensen, Claus B; Göring, Harald H H; Karlskov-Mortensen, Peter; Archibald, Alan L; Fredholm, Merete; Thamsborg, Stig M

    2012-04-01

    Helminths almost invariably have an over-dispersed distribution in the host population. Human and animal studies have provided evidence suggesting that a large part of this variation is due to host genetic factors. Recently, the heritability for roundworm (Ascaris suum) infection levels in pigs was estimated to be 0.45. We used single nucleotide polymorphism markers to perform a whole-genome scan on 195 pigs experimentally infected with A. suum. A putative quantitative trait locus for worm burden on chromosome 4 covering 2.5 Mbp was identified by measured genotype analysis, although none of the SNPs reached genome-wide significance. To validate the putative quantitative trait locus, we genotyped two of the SNPs within the region in unrelated, informative animals exposed to experimental or natural infections and from which we had worm counts and/or faecal egg counts; the validation studies showed that one of the SNPs (TXNIP) was associated with total worm burden (P < 0.001) and adult worm burden(P < 0.0001), whereas the other SNP (ARNT) was associated with adult worm burden (P < 0.025) in these populations. We were thus able to confirm the existence of the quantitative trait locus on chromosome 4.This is to our knowledge the first report of a quantitative trait locus associated with helminth burden in pigs.

  15. Neuroendocrine activation during combined mental and physical stress in women depends on trait anxiety and the phase of the menstrual cycle.

    Science.gov (United States)

    Hlavacova, Natasa; Wawruch, Martin; Tisonova, Jana; Jezova, Daniela

    2008-12-01

    The aim of this study was to investigate the influence of trait anxiety and menstrual cycle phase on neuroendocrine activation during combined mental and physical stress procedure in 40 healthy female subjects. Women at the upper (anxious) and lower (nonanxious) limits of the normal range of a trait anxiety scale were exposed to the stress procedure consisting of a mental component (Stroop test) and handgrip exercise. Salivary cortisol levels, cardiovascular parameters, and cognitive performance in the Stroop test were evaluated. Stress-induced cortisol levels and the rise in systolic blood pressure were affected by both trait anxiety and menstrual cycle phase. The stress model used induced a significant cortisol elevation only in anxious women in the follicular phase. This group of women also exhibited greater increases in systolic blood pressure in response to handgrip exercise as compared to anxious ones in the luteal phase and to nonanxious women in either phase. In nonanxious women, stress-induced cortisol levels positively correlated with cognitive performance. In contrast, a negative correlation trend was observed in anxious subjects. Thus, in subjects with low but not high trait anxiety, enhanced cortisol concentrations seem to be associated with better cognitive performance. The results suggest that women with high trait anxiety exhibit greater cardiovascular and hormonal sensitivity to stress stimuli during the follicular phase.

  16. [Cardiovascular resistance to orthostatic stress in athletes after aerobic exercise].

    Science.gov (United States)

    Mel'nikov, A A; Popov, S G; Vikulov, A D

    2014-01-01

    In the paper cardiovascular resistance to orthostatic stress in the athletes in the two-hour recovery period after prolonged aerobic exercise was investigated. The reaction of the cardiac (stroke volume and cardiac output) and peripheral blood volumes in the lower and upper limbs, abdominal and neck regions in response to the tilt-test before and during two hours after exercise (30 min, heart rate = 156 +/- 8 beats/min) was determined by impedance method: It is found that: (1) at baseline distribution of blood flow in favor of the neck-region in response to the tilt-test, in spite of the decrease in cardiac output, was more efficient in athletes, that was due to a large decrease in blood flow to the lower extremities, and increased blood flow in the neck region; (2) after exercise it was established symptoms of potential orthostatic intolerance: postural hypotension and tachycardia, reduced peripheral pulse blood volume, expressed in a standing position, and reduced effectiveness of the distribution of blood flow in the direction of the neck region; (3) the abilityto effectively distribute blood flow in favor of the neck region in athletes after exercise remained elevated, which was due to a large decrease in blood flow in the abdominal region at the beginning, and in the lower limbs at the end of the recovery period.

  17. Putative resistance gene markers associated with quantitative trait loci for fire blight resistance in Malus ‘Robusta 5’ accessions

    Science.gov (United States)

    2012-01-01

    Background Breeding of fire blight resistant scions and rootstocks is a goal of several international apple breeding programs, as options are limited for management of this destructive disease caused by the bacterial pathogen Erwinia amylovora. A broad, large-effect quantitative trait locus (QTL) for fire blight resistance has been reported on linkage group 3 of Malus ‘Robusta 5’. In this study we identified markers derived from putative fire blight resistance genes associated with the QTL by integrating further genetic mapping studies with bioinformatics analysis of transcript profiling data and genome sequence databases. Results When several defined E.amylovora strains were used to inoculate three progenies from international breeding programs, all with ‘Robusta 5’ as a common parent, two distinct QTLs were detected on linkage group 3, where only one had previously been mapped. In the New Zealand ‘Malling 9’ X ‘Robusta 5’ population inoculated with E. amylovora ICMP11176, the proximal QTL co-located with SNP markers derived from a leucine-rich repeat, receptor-like protein ( MxdRLP1) and a closely linked class 3 peroxidase gene. While the QTL detected in the German ‘Idared’ X ‘Robusta 5’ population inoculated with E. amylovora strains Ea222_JKI or ICMP11176 was approximately 6 cM distal to this, directly below a SNP marker derived from a heat shock 90 family protein gene ( HSP90). In the US ‘Otawa3’ X ‘Robusta5’ population inoculated with E. amylovora strains Ea273 or E2002a, the position of the LOD score peak on linkage group 3 was dependent upon the pathogen strains used for inoculation. One of the five MxdRLP1 alleles identified in fire blight resistant and susceptible cultivars was genetically associated with resistance and used to develop a high resolution melting PCR marker. A resistance QTL detected on linkage group 7 of the US population co-located with another HSP90 gene-family member and a WRKY transcription factor

  18. Putative resistance gene markers associated with quantitative trait loci for fire blight resistance in Malus ‘Robusta 5’ accessions

    Directory of Open Access Journals (Sweden)

    Gardiner Susan E

    2012-04-01

    Full Text Available Abstract Background Breeding of fire blight resistant scions and rootstocks is a goal of several international apple breeding programs, as options are limited for management of this destructive disease caused by the bacterial pathogen Erwinia amylovora. A broad, large-effect quantitative trait locus (QTL for fire blight resistance has been reported on linkage group 3 of Malus ‘Robusta 5’. In this study we identified markers derived from putative fire blight resistance genes associated with the QTL by integrating further genetic mapping studies with bioinformatics analysis of transcript profiling data and genome sequence databases. Results When several defined E.amylovora strains were used to inoculate three progenies from international breeding programs, all with ‘Robusta 5’ as a common parent, two distinct QTLs were detected on linkage group 3, where only one had previously been mapped. In the New Zealand ‘Malling 9’ X ‘Robusta 5’ population inoculated with E. amylovora ICMP11176, the proximal QTL co-located with SNP markers derived from a leucine-rich repeat, receptor-like protein ( MxdRLP1 and a closely linked class 3 peroxidase gene. While the QTL detected in the German ‘Idared’ X ‘Robusta 5’ population inoculated with E. amylovora strains Ea222_JKI or ICMP11176 was approximately 6 cM distal to this, directly below a SNP marker derived from a heat shock 90 family protein gene ( HSP90. In the US ‘Otawa3’ X ‘Robusta5’ population inoculated with E. amylovora strains Ea273 or E2002a, the position of the LOD score peak on linkage group 3 was dependent upon the pathogen strains used for inoculation. One of the five MxdRLP1 alleles identified in fire blight resistant and susceptible cultivars was genetically associated with resistance and used to develop a high resolution melting PCR marker. A resistance QTL detected on linkage group 7 of the US population co-located with another HSP90 gene-family member and a WRKY

  19. Organizational Stressors and Job Stress Among Malaysian Managers: The Moderating Role of Personality Traits

    OpenAIRE

    Kumaresan V Sathasivam; Mohd Dahlan Hj. A. Malek; Ahmad Faris Abdullah

    2015-01-01

    Job stress is vastly present in today¡¯s organizations, and the costs of these phenomena cut across all levels of society. In recent years, researchers considering job stress in the workplace have made great strides in understanding several aspects of the stress phenomenon in the field of organizational behavior. Thus, it becomes more important that the individual variables of these job stresses are well explored and directly linked to individuals experiencing this situation, in order to ensu...

  20. Trans-Generational Effects of Mild Heat Stress on the Life History Traits of an Aphid Parasitoid

    Science.gov (United States)

    Ismaeil, Ibrahim; Doury, Géraldine; Desouhant, Emmanuel; Dubois, Françoise; Prevost, Geneviève; Couty, Aude

    2013-01-01

    Temperature changes are common in nature and insects are particularly exposed and sensitive to such variations which can be potential stresses, ultimately affecting life history traits and overall fitness. Braconids have been widely used to study the effects of temperature on host-parasitoid interactions and the present work focused on the solitary endoparasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae Aphidiidae), an efficient biological control agent commercially used against aphids such as the potato aphid Macrosiphum euphorbiae Thomas (Sternorrhyncha: Aphididae). Contrary to previous studies using heat shocks at extreme temperatures, we evaluated the effects of mild heat stresses by transferring young parasitoid adults from the constant temperature of 20°C to either a warm (25°C) or hot (28°C) temperature, for either 1 h or 48 h. Such treatments are consistent with situations commonly experienced by parasitoids when moved from their rearing conditions to greenhouses or field conditions. The effects were evaluated both on the heat stressed A. ervi adults (G0) (immediate effects) and on their first generation (G1) progeny (trans-generational effects). G0 wasps’ mortality was significantly affected by the temperature in interaction with the duration of the stress. Longevity of G0 wasps surviving the heat stress was negatively affected by the temperature and females lived longer than males. Heat stress applied to A. ervi parents also had consequences on their G1 progeny whose developmental time, rates of mummification and percentage of parasitoid completing total development were negatively affected. Surprisingly, the egg load at emergence of the G1 female progeny was increased when their mothers had been submitted to a mild heat stress of 25°C or 28°C. These results clearly demonstrate trans-generational phenotypic plasticity, showing that adaptation to thermal stresses may be achieved via maternal effects. This study also sheds light on the

  1. Trans-generational effects of mild heat stress on the life history traits of an aphid parasitoid.

    Directory of Open Access Journals (Sweden)

    Ibrahim Ismaeil

    Full Text Available Temperature changes are common in nature and insects are particularly exposed and sensitive to such variations which can be potential stresses, ultimately affecting life history traits and overall fitness. Braconids have been widely used to study the effects of temperature on host-parasitoid interactions and the present work focused on the solitary endoparasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae Aphidiidae, an efficient biological control agent commercially used against aphids such as the potato aphid Macrosiphum euphorbiae Thomas (Sternorrhyncha: Aphididae. Contrary to previous studies using heat shocks at extreme temperatures, we evaluated the effects of mild heat stresses by transferring young parasitoid adults from the constant temperature of 20°C to either a warm (25°C or hot (28°C temperature, for either 1 h or 48 h. Such treatments are consistent with situations commonly experienced by parasitoids when moved from their rearing conditions to greenhouses or field conditions. The effects were evaluated both on the heat stressed A. ervi adults (G0 (immediate effects and on their first generation (G1 progeny (trans-generational effects. G0 wasps' mortality was significantly affected by the temperature in interaction with the duration of the stress. Longevity of G0 wasps surviving the heat stress was negatively affected by the temperature and females lived longer than males. Heat stress applied to A. ervi parents also had consequences on their G1 progeny whose developmental time, rates of mummification and percentage of parasitoid completing total development were negatively affected. Surprisingly, the egg load at emergence of the G1 female progeny was increased when their mothers had been submitted to a mild heat stress of 25°C or 28°C. These results clearly demonstrate trans-generational phenotypic plasticity, showing that adaptation to thermal stresses may be achieved via maternal effects. This study also sheds light on

  2. No Correlation of Morpho-Agronomic Traits of Phaseolus vulgaris (Fabaceae) Genotypes and Resistance to Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Guzzo, E C; Vendramim, J D; Chiorato, A F; Lourenção, A L; Carbonell, S A M; Corrêa, O M B

    2015-12-01

    Resistance of common bean (Phaseolus vulgaris) varieties is an important tool to control Acanthoscelides obtectus (Say) and Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae: Bruchinae) worldwide. However, bioassays to characterize the resistance of a genotype can be difficult to perform. Therefore, the current study sought to correlate the morpho-agronomic traits of P. vulgaris genotypes with their resistance to A. obtectus and Z. subfasciatus to facilitate genotype characterization. Bean samples of each genotype were infested with newly emerged insect couples, and the number of adults obtained in each genotype was quantified (value used as a resistance parameter). The resistance index was calculated by dividing the number of adults obtained in each genotype by the one obtained in the cultivar Bolinha, used as the standard for susceptibility. Fifty genotypes were evaluated for A. obtectus and 202 for Z. subfasciatus. All genotypes were characterized according to their resistance to each insect and 18 other morpho-agronomic traits, for a total of 19 descriptors. Principal component analyses did not show any correlation between insect resistance and the morpho-agronomic traits of the genotypes. Further, the thousand seeds weight (TSW), which is indicative of the genotype center of origin was tested considering genotypes from Mesoamerican with low TSW, while those from Andean with high TSW. Thus, the lack of correlation between genotype resistance and TSW indicates that resistance to A. obtectus and Z. subfasciatus in P. vulgaris is not related to the host center of origin.

  3. Candidate Quantitative Trait Loci Genes for Spatial Learning, Memory and Responsiveness to Stress (Preprint)

    Science.gov (United States)

    2017-04-13

    during or after chronic stress (Claessens et al., 2011, Ebner & Singewald, 2017, Mcewen & Stellar, 1993). Indeed, both stress responsiveness and...2009) Genetic foundations of human intelligence. Human Genetics, 126, 215-232. Ebner , K. & Singewald, N. (2017) Individual differences in stress

  4. Genetic control and combining ability of flag leaf area and relative water content traits of bread wheat cultivars under drought stress condition

    Directory of Open Access Journals (Sweden)

    Golparvar Ahmad Reza

    2013-01-01

    Full Text Available In order to compare mode of inheritance, combining ability, heterosis and gene action in genetic control of traits flag leaf area, relative water content and grain filling rate of bread wheat under drought stress, a study was conducted on 8 cultivars using of Griffing’s method2 in fixed model. Mean square of general combining ability was significant also for all traits and mean square of specific combining ability was significant also for all traits except relative water content of leaf which show importance of both additive and dominant effects of genes in heredity of these traits under stress. GCA to SCA mean square ratio was significant for none of traits. Results of this study showed that non additive effects of genes were more important than additive effect for all traits. According to results we can understand that genetic improvement of mentioned traits will have low genetic efficiency by selection from the best crosses of early generations. Then it is better to delay selection until advanced generations and increase in heritability of these traits.

  5. Glycopeptide resistance: Links with inorganic phosphate metabolism and cell envelope stress.

    Science.gov (United States)

    Santos-Beneit, Fernando; Ordóñez-Robles, María; Martín, Juan F

    2017-06-01

    Antimicrobial resistance is a critical health issue today. Many pathogens have become resistant to many or all available antibiotics and limited new antibiotics are in the pipeline. Glycopeptides are used as a 'last resort' antibiotic treatment for many bacterial infections, but worryingly, glycopeptide resistance has spread to very important pathogens such as Enterococcus faecium and Staphylococcus aureus. Bacteria confront multiple stresses in their natural environments, including nutritional starvation and the action of cell-wall stressing agents. These stresses impact bacterial susceptibility to different antimicrobials. This article aims to review the links between glycopeptide resistance and different stresses, especially those related with cell-wall biosynthesis and inorganic phosphate metabolism, and to discuss promising alternatives to classical antibiotics to avoid the problem of antimicrobial resistance. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Transgenic crops with an improved resistance to biotic stresses. A review

    Directory of Open Access Journals (Sweden)

    Tohidfar, M.

    2015-01-01

    Full Text Available Introduction. Pests, diseases and weeds (biotic stresses are significant limiting factors for crop yield and production. However, the limitations associated with conventional breeding methods necessitated the development of alternative methods for improving new varieties with higher resistance to biotic stresses. Molecular techniques have developed applicable methods for genetic transformation of a wide range of plants. Genetic engineering approach has been demonstrated to provide enormous options for the selection of the resistance genes from different sources to introduce them into plants to provide resistance against different biotic stresses. Literature. In this review, we focus on strategies to achieve the above mentioned objectives including expression of insecticidal, antifungal, antibacterial, antiviral resistance and herbicide detoxification for herbicide resistance. Conclusion. Regardless of the concerns about commercialization of products from genetically modified (GM crops resistant to biotic stresses, it is observed that the cultivation area of these crops is growing fast each year. Considering this trend, it is expected that production and commercialization of GM crops resistant to biotic stresses will continue to increase but will also extend to production of crops resistant to abiotic stresses (e.g. drought, salinity, etc. in a near future.

  7. Induced resistance in tomato by SAR activators during predisposing salinity stress

    Directory of Open Access Journals (Sweden)

    Matthew Francis Pye

    2013-05-01

    Full Text Available Plant activators are chemicals that induce disease resistance. The phytohormone salicylic acid (SA is a crucial signal for systemic acquired resistance (SAR, and SA-mediated resistance is a target of several commercial plant activators, including Actigard (1,2,3-benzothiadiazole-7-thiocarboxylic acid-s-methyl-ester, BTH and Tiadinil (N-(3-chloro-4-methylphenyl-4-methyl-1,2,3-thiadiazole-5-carboxamide, TDL. BTH and TDL were examined for their impact on abscisic acid (ABA-mediated, salt-induced disease predisposition in tomato seedlings. A brief episode of salt stress to roots significantly increased the severity of disease caused by Pseudomonas syringae pv. tomato (Pst and Phytophthora capsici relative to non-stressed plants. Root treatment with TDL induced resistance to Pst in leaves and provided protection in both non-stressed and salt-stressed seedlings in WT and highly susceptible NahG plants. Non-stressed and salt-stressed ABA-deficient sitiens mutants were highly resistant to Pst. Neither TDL nor BTH induced resistance to root infection by P. capsici, nor did they moderate the salt-induced increment in disease severity. Root treatment with these plant activators increased the levels of ABA in roots and shoots similar to levels observed in salt-stressed plants. The results indicate that SAR activators can protect tomato plants from bacterial speck disease under predisposing salt stress, and suggest that some SA-mediated defense responses function sufficiently in plants with elevated levels of ABA.

  8. Induced resistance in tomato by SAR activators during predisposing salinity stress.

    Science.gov (United States)

    Pye, Matthew F; Hakuno, Fumiaki; Macdonald, James D; Bostock, Richard M

    2013-01-01

    Plant activators are chemicals that induce disease resistance. The phytohormone salicylic acid (SA) is a crucial signal for systemic acquired resistance (SAR), and SA-mediated resistance is a target of several commercial plant activators, including Actigard (1,2,3-benzothiadiazole-7-thiocarboxylic acid-S-methyl-ester, BTH) and Tiadinil [N-(3-chloro-4-methylphenyl)-4-methyl-1,2,3-thiadiazole-5-carboxamide, TDL]. BTH and TDL were examined for their impact on abscisic acid (ABA)-mediated, salt-induced disease predisposition in tomato seedlings. A brief episode of salt stress to roots significantly increased the severity of disease caused by Pseudomonas syringae pv. tomato (Pst) and Phytophthora capsici relative to non-stressed plants. Root treatment with TDL induced resistance to Pst in leaves and provided protection in both non-stressed and salt-stressed seedlings in wild-type and highly susceptible NahG plants. Non-stressed and salt-stressed ABA-deficient sitiens mutants were highly resistant to Pst. Neither TDL nor BTH induced resistance to root infection by Phytophthora capsici, nor did they moderate the salt-induced increment in disease severity. Root treatment with these plant activators increased the levels of ABA in roots and shoots similar to levels observed in salt-stressed plants. The results indicate that SAR activators can protect tomato plants from bacterial speck disease under predisposing salt stress, and suggest that some SA-mediated defense responses function sufficiently in plants with elevated levels of ABA.

  9. [Parental Stress and psychopathological traits in children and adolescents. A controlled study].

    Science.gov (United States)

    Gatta, Michela; Balottin, Laura; Mannarini, Stefania; Birocchi, Valentina; Del Col, Lara; Battistella, Pier Antonio

    2016-01-01

    Since parental stress and family empowerment were shown to influence children's and adolescents' outcome, especially in the case of psychotherapeutic treatments, the present study aims to deeply explore factors that are likely to impact on stress and empowerment in parents of children with a psychiatric diagnosis. Parenting stress and empowerment have been compared between 45 parents of children with a psychiatric disorder and 96 parents of children without psychiatric disorders. Parenting stress appeared to be higher in patients' parents and it varied according to disorder severity, while socio-demographic variables seemed to influence the stress levels only to a slight extent. Moreover parental stress and empowerment influenced each other within the parental couple. Developing interventions aimed to support parenting and to involve fathers in the parent-child relationship, focused on increasing parents empowerment and self-efficacy, could contribute to decrease stress and positively influence children's psychopathology.

  10. Novel quantitative trait loci for partial resistance to Phytophthora sojae in soybean PI 398841

    Science.gov (United States)

    Phytophthora root and stem rot caused by Phytophthora sojae Kaufmann and Gerdmann is one of the most severe soybean [Glycine max (L.) Merr] diseases in the US. Partial resistance is as effective in managing this disease as single-gene (Rps) mediated resistance and is more durable. The objective of t...

  11. Phenotypic and genotypic antimicrobial resistance traits of foodborne Staphylococcus aureus isolates from Shanghai

    Science.gov (United States)

    Staphylococcus aureus is a recognized pathogen in humans, which causes nosocomial infections and food poisoning. The transmission of antibiotic resistant S. aureus (ARSA), especially methicillin-resistant S. aureus (MRSA), between food products and humans has become a serious problem. Hence, it is n...

  12. Quantitative trait loci from two genotypes of oat (Avena sativa L.) conditioning resistance to Puccinia coronata

    Science.gov (United States)

    Developing oat cultivars with partial resistance to crown rust would be beneficial for disease management. Two recombinant inbred line (RIL) populations were derived by crossing the susceptible cultivar ‘Provena’ with two partially resistant sources, ‘CDC Boyer’ and breeding line 94197A1-9-2-2-2-5. ...

  13. Post-traumatic stress disorder and depression co-occurrence: Structural relations among disorder constructs and trait and symptom dimensions.

    Science.gov (United States)

    Post, Loren M; Feeny, Norah C; Zoellner, Lori A; Connell, Arin M

    2016-12-01

    Post-traumatic stress disorder (PTSD) and major depressive disorder (MDD) in response to trauma co-occur at high rates. A better understanding of the nature of this co-occurrence is critical to developing an accurate conceptualization of the disorders. This study examined structural relations among the PTSD and MDD constructs and trait and symptom dimensions within the framework of the integrative hierarchical model of anxiety and depression. Study participants completed clinician-rated and self-report measures during a pre-treatment assessment. The sample consisted of 200 treatment-seeking individuals with a primary DSM-IV PTSD diagnosis. Structural equation modelling was used to examine the relationship between the constructs. The trait negative affect/neuroticism construct had a direct effect on both PTSD and MDD. The trait positive affect/extraversion construct had a unique, negative direct effect on MDD, and PTSD had a unique, direct effect on the physical concerns symptoms construct. An alternative model with the PTSD and MDD constructs combined into an overall general traumatic stress construct produced a decrement in model fit. These findings provide a clearer understanding of the relationship between co-occurring PTSD and MDD as disorders with shared trait negative affect/neuroticism contributing to the overlap between them and unique trait positive affect/extraversion and physical concerns differentiating them. Therefore, PTSD and MDD in response to trauma may be best represented as two distinct, yet strongly related constructs. In assessing individuals who have been exposed to trauma, practitioners should recognize that co-occurring PTSD and MDD appears to be best represented as two distinct, yet strongly related constructs. Negative affect may be the shared vulnerability directly influencing both PTSD and MDD; however, in the presence of both PTSD and MDD, low positive affect appears to be more specifically related to MDD and fear of physical

  14. Species performance: The relationship between nutrient availability, life history traits and stress [Chapter 8

    Science.gov (United States)

    Jeremy J. James

    2012-01-01

    Differences in species performance (i.e. how a species captures and utilizes resources to maintain and increase population size), influences the rate and direction of plant community change (Sheley et al., 2006). Species performance is determined by a number of interacting factors. This includes resource supply rates, physiological traits that determine how a species...

  15. 'MN1606SP' by 'Spencer' filial soybean population reveals novel quantitative trait loci and interactions among loci conditioning SDS resistance.

    Science.gov (United States)

    Luckew, Alexander S; Swaminathan, Sivakumar; Leandro, Leonor F; Orf, James H; Cianzio, Silvia R

    2017-10-01

    Four novel QTL and interactions among QTL were identified in this research, using as a parent line the most SDS-resistant genotype within soybean cultivars of the US early maturity groups. Soybean sudden death syndrome (SDS) reduces soybean yield in most of the growing areas of the world. The causal agent of SDS, soilborne fungus Fusarium virguliforme (Fv), releases phytotoxins taken up by the plant to produce chlorosis and necrosis in the leaves. Planting resistant cultivars is the most successful management practice to control the disease. The objective of this study was to identify quantitative trait loci (QTL) associated with the resistance response of MN1606SP to SDS. A mapping population of F 2:3 lines created by crossing the highly resistant cultivar 'MN1606SP' and the susceptible cultivar 'Spencer' was phenotyped in the greenhouse at three different planting times, each with three replications. Plants were artificially inoculated using SDS infested sorghum homogeneously mixed with the soil. Data were collected on three disease criteria, foliar disease incidence (DI), foliar leaf scorch disease severity (DS), and root rot severity. Disease index (DX) was calculated as DI × DS. Ten QTL were identified for the different disease assessment criteria, three for DI, four for DX, and three for root rot severity. Three QTL identified for root rot severity and one QTL for disease incidence are considered novel, since no previous reports related to these QTL are available. Among QTL, two interactions were detected between four different QTL. The interactions suggest that resistance to SDS is not only dependent on additive gene effects. The novel QTL and the interactions observed in this study will be useful to soybean breeders for improvement of SDS resistance in soybean germplasm.

  16. Identification of Cephalosporium stripe resistance quantitative trait loci in two recombinant inbred line populations of winter wheat.

    Science.gov (United States)

    Vazquez, M Dolores; Zemetra, Robert; Peterson, C James; Mundt, Christopher C

    2015-02-01

    Identification of genome regions linked to Cephalosporium stripe resistance across two populations on chromosome 3BS, 4BS, 5AL, C5BL. Results were compared to a similar previous study. Cephalosporium stripe is a vascular wilt disease of winter wheat (Triticum aestivum L.) caused by the soil-borne fungus Cephalosporium gramineum Nisikado & Ikata. In the USA it is known to be a recurring disease when susceptible cultivars are grown in the wheat-growing region of Midwest and Pacific Northwest. There is no complete resistance in commercial wheat cultivars, although the use of moderately resistant cultivars reduces the disease severity and the amount of inoculum in subsequent seasons. The goal of this study was to detect and to compare chromosomal regions for resistance to Cephalosporium stripe in two winter wheat populations. Field inoculation was performed and Cephalosporium stripe severity was visually scored as percent of prematurely ripening heads (whiteheads) per plot. 'Tubbs'/'NSA-98-0995' and 'Einstein'/'Tubbs', each comprising a cross of a resistant and a susceptible cultivar, with population sizes of 271 and 259 F (5:6) recombinant inbred lines, respectively, were genotyped and phenotyped across four environments. In the quantitative trait loci (QTL) analysis, six and nine QTL were found, explaining in total, around 30 and 50 % of the phenotypic variation in 'Tubbs'/'NSA-98-0995' and 'Einstein'/'Tubbs', respectively. The QTL with the largest effect from both 'NSA-98-0995' and 'Einstein' was on chromosome 5AL.1 and linked to marker gwm291. Several QTL with smaller effects were identified in both populations on chromosomes 5AL, 6BS, and 3BS, along with other QTL identified in just one population. These results indicate that resistance to Cephalosporium stripe in both mapping populations was of a quantitative nature.

  17. Quantitative Trait Loci in Sweet Corn Associated with Partial Resistance to Stewart's Wilt, Northern Corn Leaf Blight, and Common Rust.

    Science.gov (United States)

    Brown, A F; Juvik, J A; Pataky, J K

    2001-03-01

    ABSTRACT Partial resistance to Stewart's wilt (Erwina stewartii, syn. Pantoea stewartii), northern corn leaf blight (NCLB) (Exserohilum turcicum), and common rust (Puccinia sorghi) was observed in an F(2:3) population developed from a cross between the inbred sweet corn lines IL731a and W6786. The objective of this study was to identify quantitative trait loci (QTL) associated with partial resistance using restriction fragment length polymorphic markers. Phenotypic data were collected for 2 years for Stewart's wilt, NCLB, and common rust but, due to significant family-environment interaction, analysis was conducted individually on data from each year. In 2 years of evaluation for the three diseases, a total of 33 regions in the maize genome were associated with partial resistance describing from 5.9 to 18% of the total phenotypic variability. Of six regions common in both years, three were associated with partial resistance to Stewart's wilt (chromosomes 4:07, 5:03, and 6:04), one was associated with NCLB (chromosome 9:05), and two were associated with common rust (chromosomes 2:04 and 3:04). The rust QTL on 3S mapped to within 20 cM of the rp3 locus and explained 17.7% of the phenotypic variability. Some of the QTL associated with partial resistance to the three diseases have been reported previously, and some are described here for the first time. Results suggest it may be possible to consolidate QTL from various elite backgrounds in a manner analogous to the pyramiding of major resistance genes. We also report here on two QTL associated with anthocyanin production on chromosomes 10:6 and 5:03 in the general location of the a2 gene.

  18. A shift to organismal stress resistance in programmed cell death mutants.

    Directory of Open Access Journals (Sweden)

    Meredith E Judy

    Full Text Available Animals have many ways of protecting themselves against stress; for example, they can induce animal-wide, stress-protective pathways and they can kill damaged cells via apoptosis. We have discovered an unexpected regulatory relationship between these two types of stress responses. We find that C. elegans mutations blocking the normal course of programmed cell death and clearance confer animal-wide resistance to a specific set of environmental stressors; namely, ER, heat and osmotic stress. Remarkably, this pattern of stress resistance is induced by mutations that affect cell death in different ways, including ced-3 (cell death defective mutations, which block programmed cell death, ced-1 and ced-2 mutations, which prevent the engulfment of dying cells, and progranulin (pgrn-1 mutations, which accelerate the clearance of apoptotic cells. Stress resistance conferred by ced and pgrn-1 mutations is not additive and these mutants share altered patterns of gene expression, suggesting that they may act within the same pathway to achieve stress resistance. Together, our findings demonstrate that programmed cell death effectors influence the degree to which C. elegans tolerates environmental stress. While the mechanism is not entirely clear, it is intriguing that animals lacking the ability to efficiently and correctly remove dying cells should switch to a more global animal-wide system of stress resistance.

  19. Transfer of anthracnose resistance and pod coiling traits from Medicago arborea to M. sativa by sexual reproduction.

    Science.gov (United States)

    Armour, D J; Mackie, J M; Musial, J M; Irwin, J A G

    2008-07-01

    Five asymmetric hybrid plants were obtained between Medicago sativa (2n = 4x = 32) and Medicago arborea (2n = 4x = 32) through sexual reproduction and the use of a cytoplasmically male sterile M. sativa genotype. Over 2,000 pollinations were made to obtain these hybrids. Amplified fragment length polymorphism (AFLP) analysis showed that in the most studied hybrid (WA2273), 4% of the bands unique to the M. arborea parent were present, versus 72% for the unique M. sativa bands. This suggests that only a single M. arborea chromosome or chromosome parts has been transferred. WA2273 had 7% of AFLP bands which were not present in either parent, which is suggestive of chromosome rearrangements as would be expected if only chromosome parts or a single part had been transferred from M. arborea. Phenotypic evidence for hybridity was obtained for pod coiling (1.4 coils in WA2273 versus three coils in the M. sativa parent and its self and testcross populations, and one coil in M. arborea), and Colletotrichum trifolii race 2 resistance (transferred from the resistant M. arborea parent, as the M. sativa parent and the self populations were highly susceptible). The hybrids were self sterile, but were female fertile to a high level when crossed with 4x, but not 2x, M. sativa, indicating they were at or near 4x. Both the pod coiling trait and anthracnose resistance segregated in the progeny of testcrosses between WA2273 and M. sativa. The work demonstrates that agronomically useful traits can be introgressed into M. sativa from M. arborea by use of male sterile M. sativa and sexual reproduction.

  20. Trait Emotional Intelligence, Anxiety Sensitivity, and Experiential Avoidance in Stress Reactivity and Their Improvement Through Psychological Methods

    Directory of Open Access Journals (Sweden)

    Kenneth Choi

    2014-05-01

    Full Text Available Stress pervades daily society, often with deleterious consequences for those prone to react intensely to it. Intervention techniques to attenuate stress reactivity are thus paramount. With that goal in mind, researchers have sought to identify and alter malleable psychological dispositional variables that influence stress reactivity. Trait emotional intelligence (TEI, anxiety sensitivity (AS, and experiential avoidance (EA are increasingly receiving attention in these research efforts. The self-reported emotional component of stress reactivity has been emphasized in investigations and is our focus. Specifically, this paper overviews the role of TEI, AS, and EA in self-reported stress responses. We also discuss empirically supported psychological methods to adjust suboptimal levels of these variables in normal populations. Both psycho-educational (information, skills and mindfulness-based interventions (specific mindfulness therapies or components are covered. Findings include that (1 TEI, AS, and EA are each correlated with the emotional component of stress reactivity to both naturalistic and lab-based stressors; (2 preliminary support currently exists for psycho-educational intervention of TEI and AS but is lacking for EA; (3 adequate evidence supports mindfulness-based interventions to target EA, with very limited but encouraging findings suggesting mindfulness methods improve TEI and AS; and (4 although more research is needed, stress management approaches based on mindfulness may well target all three of these psychological variables and thus appear particularly promising. Encouragingly, some methods to modify dispositional variables (e.g., a mindfulness-based format of guided self-help are easily disseminated and potentially applicable to the general public.

  1. The importance of trait emotional intelligence and feelings in the prediction of perceived and biological stress in adolescents: hierarchical regressions and fsQCA models.

    Science.gov (United States)

    Villanueva, Lidón; Montoya-Castilla, Inmaculada; Prado-Gascó, Vicente

    2017-07-01

    The purpose of this study is to analyze the combined effects of trait emotional intelligence (EI) and feelings on healthy adolescents' stress. Identifying the extent to which adolescent stress varies with trait emotional differences and the feelings of adolescents is of considerable interest in the development of intervention programs for fostering youth well-being. To attain this goal, self-reported questionnaires (perceived stress, trait EI, and positive/negative feelings) and biological measures of stress (hair cortisol concentrations, HCC) were collected from 170 adolescents (12-14 years old). Two different methodologies were conducted, which included hierarchical regression models and a fuzzy-set qualitative comparative analysis (fsQCA). The results support trait EI as a protective factor against stress in healthy adolescents and suggest that feelings reinforce this relation. However, the debate continues regarding the possibility of optimal levels of trait EI for effective and adaptive emotional management, particularly in the emotional attention and clarity dimensions and for female adolescents.

  2. Stress, emotion regulation and cognitive performance: the predictive contributions of trait and state relative frontal EEG alpha asymmetry.

    Science.gov (United States)

    Goodman, Ronald N; Rietschel, Jeremy C; Lo, Li-Chuan; Costanzo, Michelle E; Hatfield, Bradley D

    2013-02-01

    The relationship between trait and state measures of frontal lobe EEG alpha-band asymmetry in regard to indexing the approach-withdrawal dimension of emotion is unclear. The comparative predictive power of these constructs to explain emotion regulation and cognitive performance was examined under varying degrees of emotional challenge. The Capability Model posits the neural underpinnings of the relative difference in electrical activity between the left and right frontal lobes as a situational mechanism possibly indexing prefrontal-amygdalar interactions and psychological state. EEG, skin conductance, heart rate and acoustic startle amplitude were collected during a working memory task under three increasing levels of stress (final level was threat of shock). During threat of shock participants with higher state asymmetry exhibited greater emotion regulation compared to those with lower scores as indexed by significant attenuation of eyeblink startle magnitudes. The trait measure of frontal EEG asymmetry failed to account for significant variability in emotion regulation. Results implicate state-specific relative left frontal lobe activity as having an adaptive role in the regulation of emotion during cognitive challenge, but only under conditions of sufficient stress. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Implications of Environmental Stress during Seed Development on Reproductive and Seed Bank Persistence Traits in Wild Oat (Avena fatua L.

    Directory of Open Access Journals (Sweden)

    E. Patrick Fuerst

    2013-07-01

    Full Text Available Weeds produce seed under a wide range of conditions, depending on timing of emergence, prevailing crop, soil microsites, and climatic conditions, among other factors. We hypothesized that the maturation environment during weed seed development will influence reproductive allocation and seed persistence traits, such as seed dormancy and vigor, and needs to be considered when formulating weed management strategies. This research evaluated the effects of shade and drought stress on reproductive allocation, seed dormancy and seed vigor in select lines of wild oat (Avena fatua L.. Plants were grown in the greenhouse under drought stress and shade. Harvested seed were subjected to controlled after-ripening and aging regimes. Drought and shade reduced reproductive allocation and resulted in seed with less intense primary dormancy compared to the plants grown under resource-rich conditions, but had no apparent effect on seed vigor. Our data provide additional support to the hypothesis that seed dormancy within a species is a highly plastic trait that can be strongly influenced by the growth conditions of the mother plant. Such plasticity may have important implications for establishing ecologically-based weed control criteria on which threshold-based weed management systems are implemented.

  4. [Regulating acid stress resistance of lactic acid bacteria--a review].

    Science.gov (United States)

    Wu, Chongde; Huang, Jun; Zhou, Rongqing

    2014-07-04

    As cell factories, lactic acid bacteria are widely used in food, agriculture, pharmaceutical and other industries. Acid stress is one the important survival challenges encountered by lactic acid bacteria both in fermentation process and in the gastrointestinal tract. Recently, the development of systems biology and metabolic engineering brings unprecedented opportunity for further elucidating the acid tolerance mechanisms and improving the acid stress resistance of lactic acid bacteria. This review addresses physiological mechanisms of lactic acid bacteria during acid stress. Moreover, strategies to improve the acid stress resistance of lactic acid were proposed.

  5. Identification of plant genes for abiotic stress resistance

    NARCIS (Netherlands)

    Dixit, S.A.

    2008-01-01

    As water and salt stresses occur frequently and can affect many habitats, plants have developed several strategies to cope with these challenges: either adaptation mechanisms, which allow them to survive the adverse conditions, or specific growth habits to avoid stress conditions. Stress-tolerant

  6. Antimicrobial resistance and virulence traits of Enterococcus faecalis from primary endodontic infections.

    Science.gov (United States)

    Lins, Renata Ximenes; de Oliveira Andrade, Aurimar; Hirata Junior, Raphael; Wilson, Melanie J; Lewis, Michael A O; Williams, David W; Fidel, Rivail Antonio Sergio

    2013-09-01

    To determine the phenotypic and molecular characteristics of Enterococcus faecalis recovered from primary endodontic infections in Brazilian patients. Twenty isolates of E. faecalis recovered from 43 Brazilian patients with primary endodontic infections were identified by biochemical profiling (API20Strep) and 16S rDNA sequencing. Antimicrobial susceptibility was ascertained by agar dilution, using the recommended protocol of the Clinical and Laboratory Standards Institute (CLSI). PCR with validated primers was used to detect genes associated with antibiotic resistance and specific virulence factors. All isolates were deemed susceptible to penicillin G, erythromycin and vancomycin. However, nine isolates had a minimum inhibitory concentration of 4μg/mL to vancomycin (the resistance breakpoint). Fourteen isolates (70% of isolates) were also resistant to tetracycline with MICs of >64μg/mL. PCR products for tetracycline resistance genes were detected in test isolates, while erythromycin and vancomycin resistance genes were not evident. Gelatinase, aggregation substance and enteroccocal surface protein genes were detected in 20, 18 and 12 isolates, respectively. Endodontic E. faecalis isolates exhibit high level of resistance to tetracycline, an antibiotic that has use in local treatment of dental infections. This opens up a much-needed debate on the role and efficacy of this antibiotic for oral infections. Furthermore, these isolates were shown to possess genes that could contribute to pathogenicity in the pulp cavity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Mapping QTLs Linked to Some Traits Related to Drought Stress in Rice

    Directory of Open Access Journals (Sweden)

    H. Sabouri

    2012-08-01

    Full Text Available Identification of markers linked to genes controlling drought tolerance is necessary to breed high-yielding rice varieties for drought-prone areas. In the current study, some traits associated with drought tolerance in rice were investigated using microsatellite marker. One hundred and ninety two individuals and families derived from a cross between two genetically divergent, Shahpasand (tolerant and IR28 (sensitive, were grown in Gonbad Kavous University to detect QTLs for traits related to drought tolerance on chromosomes 1 and 6. Linkage map was derived using 33 polymorphic markers in 2 linkage groups in parents and 192 F2 individuals. This map covered 366 cM of the rice genome. A total of 16 QTLs were detected for traits. The co-location of QTLs for traits for drought tolerance was shown to be on chromosome 1 in RM8115-RM5638 and chromosome 6 in RM7434-RM162 and RM4608-RM217 intervals. The results showed that QTLs controlling LFI (qLFI-1 overlapped with the QTLs for leaf rolling (qROL-1 on chromosome 1. Three QTLs were mapped for fertility (FER. Two QTLs were showed the large effects on the ROL and FER that explained 14.11% and 14.65%, respectively, of the total phenotypic variations. These QTLs may be useful for development of new varieties with a high level of grain yield under drought conditions. Since these regions explained significant percentage of the phenotypic variations, they have potential for being applied in selection programs using a marker for drought tolerance.

  8. Fine mapping of quantitative trait loci for mastitis resistance on bovine chromosome 11

    DEFF Research Database (Denmark)

    Schulman, N F; Sahana, G; Iso-Touru, T

    2009-01-01

    Quantitative trait loci (QTL) affecting clinical mastitis (CM) and somatic cell score (SCS) were mapped on bovine chromosome 11. The mapping population consisted of 14 grandsire families belonging to three Nordic red cattle breeds: Finnish Ayrshire (FA), Swedish Red and White (SRB) and Danish Red....... The families had previously been shown to segregate for udder health QTL. A total of 524 progeny tested bulls were included in the analysis. A linkage map including 33 microsatellite and five SNP markers was constructed. We performed combined linkage disequilibrium and linkage analysis (LDLA) using the whole...

  9. Phenotypic landscape of non-conventional yeast species for different stress tolerance traits desirable in bioethanol fermentation.

    Science.gov (United States)

    Mukherjee, Vaskar; Radecka, Dorota; Aerts, Guido; Verstrepen, Kevin J; Lievens, Bart; Thevelein, Johan M

    2017-01-01

    Non-conventional yeasts present a huge, yet barely exploited, resource of yeast biodiversity for industrial applications. This presents a great opportunity to explore alternative ethanol-fermenting yeasts that are more adapted to some of the stress factors present in the harsh environmental conditions in second-generation (2G) bioethanol fermentation. Extremely tolerant yeast species are interesting candidates to investigate the underlying tolerance mechanisms and to identify genes that when transferred to existing industrial strains could help to design more stress-tolerant cell factories. For this purpose, we performed a high-throughput phenotypic evaluation of a large collection of non-conventional yeast species to identify the tolerance limits of the different yeast species for desirable stress tolerance traits in 2G bioethanol production. Next, 12 multi-tolerant strains were selected and used in fermentations under different stressful conditions. Five strains out of which, showing desirable fermentation characteristics, were then evaluated in small-scale, semi-anaerobic fermentations with lignocellulose hydrolysates. Our results revealed the phenotypic landscape of many non-conventional yeast species which have not been previously characterized for tolerance to stress conditions relevant for bioethanol production. This has identified for each stress condition evaluated several extremely tolerant non-Saccharomyces yeasts. It also revealed multi-tolerance in several yeast species, which makes those species good candidates to investigate the molecular basis of a robust general stress tolerance. The results showed that some non-conventional yeast species have similar or even better fermentation efficiency compared to S. cerevisiae in the presence of certain stressful conditions. Prior to this study, our knowledge on extreme stress-tolerant phenotypes in non-conventional yeasts was limited to only few species. Our work has now revealed in a systematic way the

  10. Two alternative recessive quantitative trait loci influence resistance to spring black stem and leaf spot in Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Oliver Richard P

    2008-03-01

    Full Text Available Abstract Background Knowledge of the genetic basis of plant resistance to necrotrophic pathogens is incomplete and has been characterised in relatively few pathosystems. In this study, the cytology and genetics of resistance to spring black stem and leaf spot caused by Phoma medicaginis, an economically important necrotrophic pathogen of Medicago spp., was examined in the model legume M. truncatula. Results Macroscopically, the resistant response of accession SA27063 was characterised by small, hypersensitive-like spots following inoculation while the susceptible interaction with accessions A17 and SA3054 showed necrotic lesions and spreading chlorosis. No unique cytological differences were observed during early infection (2 populations segregating for resistance to spring black stem and leaf spot were established between SA27063 and the two susceptible accessions, A17 and SA3054. The cross between SA27063 and A17 represented a wider cross than between SA27063 and SA3054, as evidenced by higher genetic polymorphism, reduced fertility and aberrant phenotypes of F2 progeny. In the SA27063 × A17 F2 population a highly significant quantitative trait locus (QTL, LOD = 7.37; P Phoma medicaginis one (rnpm1 genetically mapped to the top arm of linkage group 4 (LG4. rnpm1 explained 33.6% of the phenotypic variance in the population's response to infection depicted on a 1–5 scale and was tightly linked to marker AW256637. A second highly significant QTL (LOD = 6.77; P rnpm2, was located on the lower arm of LG8 in the SA27063 × SA3054 map. rnpm2 explained 29.6% of the phenotypic variance and was fine mapped to a 0.8 cM interval between markers h2_16a6a and h2_21h11d. rnpm1 is tightly linked to a cluster of Toll/Interleukin1 receptor-nucleotide binding site-leucine-rich repeat (TIR-NBS-LRR genes and disease resistance protein-like genes, while no resistance gene analogues (RGAs are apparent in the genomic sequence of the reference accession A17 at the

  11. Eggplant Resistance to the Ralstonia solanacearum Species Complex Involves Both Broad-Spectrum and Strain-Specific Quantitative Trait Loci

    Directory of Open Access Journals (Sweden)

    Sylvia Salgon

    2017-05-01

    Full Text Available Bacterial wilt (BW is a major disease of solanaceous crops caused by the Ralstonia solanacearum species complex (RSSC. Strains are grouped into five phylotypes (I, IIA, IIB, III, and IV. Varietal resistance is the most sustainable strategy for managing BW. Nevertheless, breeding to improve cultivar resistance has been limited by the pathogen’s extensive genetic diversity. Identifying the genetic bases of specific and non-specific resistance is a prerequisite to breed improvement. A major gene (ERs1 was previously mapped in eggplant (Solanum melongena L. using an intraspecific population of recombinant inbred lines derived from the cross of susceptible MM738 (S × resistant AG91-25 (R. ERs1 was originally found to control three strains from phylotype I, while being totally ineffective against a virulent strain from the same phylotype. We tested this population against four additional RSSC strains, representing phylotypes I, IIA, IIB, and III in order to clarify the action spectrum of ERs1. We recorded wilting symptoms and bacterial stem colonization under controlled artificial inoculation. We constructed a high-density genetic map of the population using single nucleotide polymorphisms (SNPs developed from genotyping-by-sequencing and added 168 molecular markers [amplified fragment length polymorphisms (AFLPs, simple sequence repeats (SSRs, and sequence-related amplified polymorphisms (SRAPs] developed previously. The new linkage map based on a total of 1,035 markers was anchored on eggplant, tomato, and potato genomes. Quantitative trait locus (QTL mapping for resistance against a total of eight RSSC strains resulted in the detection of one major phylotype-specific QTL and two broad-spectrum QTLs. The major QTL, which specifically controls three phylotype I strains, was located at the bottom of chromosome 9 and corresponded to the previously identified major gene ERs1. Five candidate R-genes were underlying this QTL, with different alleles

  12. Mycobacterium tuberculosis Exploits Asparagine to Assimilate Nitrogen and Resist Acid Stress during Infection: e1003928

    National Research Council Canada - National Science Library

    Alexandre Gouzy; Gérald Larrouy-Maumus; Daria Bottai; Florence Levillain; Alexia Dumas; Joshua B Wallach; Irène Caire-Brandli; Chantal de Chastellier; Ting-Di Wu; Renaud Poincloux; Roland Brosch; Jean-Luc Guerquin-Kern; Dirk Schnappinger; Pedro Sório de Carvalho; Yannick Poquet; Olivier Neyrolles

    2014-01-01

    .... Here we show that M. tuberculosis employs the asparagine transporter AnsP2 and the secreted asparaginase AnsA to assimilate nitrogen and resist acid stress through asparagine hydrolysis and ammonia release...

  13. Mycobacterium tuberculosis exploits asparagine to assimilate nitrogen and resist acid stress during infection

    National Research Council Canada - National Science Library

    Gouzy, Alexandre; Larrouy-Maumus, Gérald; Bottai, Daria; Levillain, Florence; Dumas, Alexia; Wallach, Joshua B; Caire-Brandli, Irène; de Chastellier, Chantal; Wu, Ting-Di; Poincloux, Renaud; Brosch, Roland; Guerquin-Kern, Jean-Luc; Schnappinger, Dirk; Sório de Carvalho, Luiz Pedro; Poquet, Yannick; Neyrolles, Olivier

    2014-01-01

    .... Here we show that M. tuberculosis employs the asparagine transporter AnsP2 and the secreted asparaginase AnsA to assimilate nitrogen and resist acid stress through asparagine hydrolysis and ammonia release...

  14. Impact of traits of metabolic syndrome on β-cell function and insulin resistance in normal fasting, normal glucose tolerant subjects.

    Science.gov (United States)

    Cubeddu, Luigi X; Hoffmann, Irene S

    2012-10-01

    Metabolic syndrome, impaired fasting glucose (IFG), and impaired glucose tolerance (IGT) predict risk for type 2 diabetes mellitus (T2DM). To determine if increased risk preceded development of these abnormalities, β-cell function and insulin resistance were assessed in euglycemic subjects with and without traits of metabolic syndrome. A total of 562 apparently healthy Latin-American subjects were screened for metabolic syndrome [National Education Cholesterol Program Adult Treatment Panel III (NECP ATP III)]. Early pancreatic insulin response ΔInsulin(0-30)/ΔGlucose(0-30), Matsuda index, disposition index (DI), and homeostasis model assessment of insulin resistance (HOMA-IR) ratio were obtained from oral glucose tolerance testing (0-180 min). ΔI(0-30)/ΔG(0-30), Matsuda index, DI, and HOMA-IR deteriorated in direct proportion with number of traits of metabolic syndrome, and with increases in glucose levels within the euglycemic range. DI was the most sensitive index. In subjects with 1, 2, 3, and 4-5 traits, DI was 21.4%, 40%, 57%, and 76% lower, respectively, than in subjects with no traits. As a single trait, abdominal obesity was associated with insulin resistance, whereas, low high-density lipoprotein cholesterol (HDL-C), alone or combined with high triglycerides, was not associated with insulin resistance or β-cell dysfunction. Combined impairments in β-cell function and insulin sensitivity were responsible for the increases in fasting and 2-h plasma glucose concentrations within the euglycemic range. Impaired β-cell function and increased insulin resistance are present much before development of metabolic syndrome, IFG, or IGT. β-Cell function and insulin sensitivity worsen in direct proportion with number of traits of metabolic syndrome and increases in glucose levels. Compared to abdominal obesity, low HDL-C±high triglycerides may bear a lesser weight in predicting risk of T2DM.

  15. Decreased Skin-Mediated Detoxification Contributes to Oxidative Stress and Insulin Resistance

    OpenAIRE

    Liu, Xing-Xing; Sun, Chang-Bin; Yang, Ting-Tong; Li, Da; Li, Chun-Yan; Tian, Yan-Jie; Guo, Ming; Cao, Yu; Zhou, Shi-Sheng

    2012-01-01

    The skin, the body's largest organ, plays an important role in the biotransformation/detoxification and elimination of xenobiotics and endogenous toxic substances, but its role in oxidative stress and insulin resistance is unclear. We investigated the relationship between skin detoxification and oxidative stress/insulin resistance by examining burn-induced changes in nicotinamide degradation. Rats were divided into four groups: sham-operated, sham-nicotinamide, burn, and burn-nicotinamide. Ra...

  16. Longer resistance of some DNA traits from BT176 maize to gastric juice from gastrointestinal affected patients.

    Science.gov (United States)

    Ferrini, A M; Mannoni, V; Pontieri, E; Pourshaban, M

    2007-01-01

    The presence of antibiotic resistance marker genes in genetically engineered plants is one of the most controversial issues related to Genetically Modified Organism (GMO)-containing food, raising concern about the possibility that these markers could increase the pool of antibiotic resistance genes. This study investigates the in vitro survival of genes bla and cryIA(b) of maize Bt176 in human gastric juice samples. Five samples of gastric juice were collected from patients affected by gastro-esophageal reflux or celiac disease and three additional samples were obtained by pH modification with NaHCO3. DNA was extracted from maize Bt176 and incubated with samples of gastric juices at different times. The survival of the target traits (bla gene, whole 1914 bp gene cry1A(b), and its 211 bp fragment) was determined using PCR. The stability of the target genes was an inverse function of their lengths in all the samples. Survival in samples from untreated subjects was below the normal physiological time of gastric digestion. On the contrary, survival time in samples from patients under anti-acid drug treatment or in samples whose pH was modified, resulted strongly increased. Our data indicate the possibility that in particular cases the survival time could be so delayed that, as a consequence, some traits of DNA could reach the intestine. In general, this aspect must be considered for vulnerable consumers (people suffering from gastrointestinal diseases related to altered digestive functionality, physiological problems or drug side-effects) in the risk analysis usually referred to healthy subjects.

  17. Get Tough, Get Toxic, or Get a Bodyguard: Identifying Candidate Traits Conferring Belowground Resistance to Herbivores in Grasses.

    Science.gov (United States)

    Moore, Ben D; Johnson, Scott N

    2016-01-01

    Grasses (Poaceae) are the fifth-largest plant family by species and their uses for crops, forage, fiber, and fuel make them the most economically important. In grasslands, which broadly-defined cover 40% of the Earth's terrestrial surface outside of Greenland and Antarctica, 40-60% of net primary productivity and 70-98% of invertebrate biomass occurs belowground, providing extensive scope for interactions between roots and rhizosphere invertebrates. Grasses invest 50-70% of fixed carbon into root construction, which suggests roots are high value tissues that should be defended from herbivores, but we know relatively little about such defenses. In this article, we identify candidate grass root defenses, including physical (tough) and chemical (toxic) resistance traits, together with indirect defenses involving recruitment of root herbivores' natural enemies. We draw on relevant literature to establish whether these defenses are present in grasses, and specifically in grass roots, and which herbivores of grasses are affected by these defenses. Physical defenses could include structural macro-molecules such as lignin, cellulose, suberin, and callose in addition to silica and calcium oxalate. Root hairs and rhizosheaths, a structural adaptation unique to grasses, might also play defensive roles. To date, only lignin and silica have been shown to negatively affect root herbivores. In terms of chemical resistance traits, nitrate, oxalic acid, terpenoids, alkaloids, amino acids, cyanogenic glycosides, benzoxazinoids, phenolics, and proteinase inhibitors have the potential to negatively affect grass root herbivores. Several good examples demonstrate the existence of indirect defenses in grass roots, including maize, which can recruit entomopathogenic nematodes (EPNs) via emission of (E)-β-caryophyllene, and similar defenses are likely to be common. In producing this review, we aimed to equip researchers with candidate root defenses for further research.

  18. DOWN-STREAM SPATIAL DISTRIBUTION OF ANTIBIOTIC RESISTANCE TRAITS ALONG METAL CONTAMINATED STREAM REACHES

    Energy Technology Data Exchange (ETDEWEB)

    Tuckfield, C; J V Mcarthur (NOEMAIL), J

    2007-04-16

    Sediment bacteria samples were collected from three streams in South Carolina, two contaminated with multiple metals (Four Mile Creek and Castor Creek), one uncontaminated (Meyers Branch), and another metal contaminated stream (Lampert Creek) in northern Washington State. Growth plates inoculated with Four Mile Creek sample extracts show bacteria colony growth after incubation on plates containing either one of two aminoglycosides (kanamycin or streptomycin), tetracycline or chloramphenocol. This study analyzes the spatial pattern of antibiotic resistance in culturable sediment bacteria in all four streams that may be due to metal contamination. We summarize the two aminoglycoside resistance measures and the 10 metals concentrations by Principal Components Analysis. Respectively, 63% and 58% of the variability was explained in the 1st principal component of each variable set. We used the respective multivariate summary metrics (i.e. 1st principal component scores) as input measures for exploring the spatial correlation between antibiotic resistance and metal concentration for each stream reach sampled. Results show a significant and negative correlation between metals scores versus aminoglycoside resistance scores and suggest that selection for metal tolerance among sediment bacteria may influence selection for antibiotic resistance differently than previously supposed.. In addition, we borrow a method from geostatistics (variography) wherein a spatial cross-correlation analysis shows that decreasing metal concentrations scores are associated with increasing aminoglycoside resistance scores as the separation distance between sediment samples decreases, but for contaminated streams only. Since these results were counter to our initial expectation and to other experimental evidence for water column bacteria, we suspect our field results are influenced by metal bioavailability in the sediments and by a contaminant promoted interaction or ''cocktail effect

  19. Integration of QTL detection and marker assisted selection for improving resistance to Fusarium head blight and important agronomic traits in wheat

    Directory of Open Access Journals (Sweden)

    Chao Lv

    2014-02-01

    Full Text Available Fusarium head blight (FHB, caused by Fusarium graminearum, is one of the most destructive wheat (Triticum aestivum L. diseases worldwide. Identification of quantitative trait loci (QTL conferring FHB resistance followed by marker assisted selection (MAS is an efficient approach to breed FHB-resistant varieties. In this study, 38 additive QTL and 18 pairs of epistatic QTL for FHB resistance were detected in four environments using a population of recombinant inbred lines (RILs derived from varieties Neixiang 188 and Yanzhan 1. Six QTL clusters were located on chromosomes 2D, 4B, 4D, 5A, 5D and 7B, suggesting possible polytrophic functions. Six elite lines with good FHB resistance and agronomic traits were selected from the same population using the associated markers. Our results suggest that MAS of multiple QTL will be effective and efficient in wheat breeding.

  20. The STRIVE-ONR Project: Stress Resistance in Virtual Environments

    Science.gov (United States)

    2015-07-29

    treatment of spider phobia: A controlled study. Behaviour Research & Therapy, 40, 983-993. doi:10.1016/S0005 HRV DURING STRESS RESILIENCE TRAINING... dog . Circulation research, 59, 178-193. doi:10.1161/01.RES.59.2.178 HRV DURING STRESS RESILIENCE TRAINING 44 Pallavicini, F., Cipresso, P...Fioramonti, J. (1989). Vagally mediated inhibition of acoustic stress-induced cortisol release by orally administered kappa-opioid substances in dogs

  1. Effects of Supplemental Chromium Propionate on Serum Lipids, Carcass Traits, and Meat Quality of Heat-Stressed Broilers.

    Science.gov (United States)

    Xiao, Fang; Ao, Degulina; Zhou, Bo; Spears, Jerry W; Lin, Xi; Huang, Yanling

    2017-04-01

    This study was conducted to investigate the effects of chromium from chromium propionate (CrPro) on serum lipids, carcass traits, and breast meat quality in heat-stressed birds. A total of 210 1-day-old male broilers were randomly allotted by initial body weight (BW) into 5 treatments with 7 replicates with 6 birds per replicate pen for 42 days. The treatments included a basal corn-soybean meal diet and basal diet supplemented with 0.2, 0.4, 0.8, or 1.6 mg Cr/kg diet. Birds had ad libitum access to feed and distilled-deionized water at normal conditions for 1-3 weeks with little or no stress, and then birds were housed under heat stress conditions with 35 ± 2 °C ambient temperature for 4-6 weeks. Results showed that serum triglyceride (TG) (P = 0.0006) and low-density lipoprotein cholesterol (LDLC) (P = 0.0038) concentrations were decreased linearly as Cr dose increased. Compared with other groups, birds receiving 0.8 or 1.6 mg Cr/kg had lower TG (P = 0.0015). Compared to control birds, birds fed diets with 0.2, 0.4, 0.8, or 1.6 mg Cr/kg supplementation had lower LDLC (P = 0.0006). However, the total cholesterol (TC) and high density lipoprotein cholesterol (HDLC) concentrations in serum were not affected by treatment (P > 0.05). No difference was observed in BW, the relative weights of breast muscle, thigh muscle and abdominal fat (P > 0.05), and breast meat quality (Ph15min, Ph24h, L(*), a(*), b(*), cooking loss, shear force) among the treatments (P > 0.05). Results from this study indicated that CrPro supplementation could be beneficial to serum lipids metabolism of heat-stressed broiler chickens by decreasing TG and LDLC contents, but had no impacts on meat quality and carcass traits of the heat-stressed broilers.

  2. Influence of priming on the physiological traits of corn seed germination under drought stress

    Directory of Open Access Journals (Sweden)

    Seyyedeh Roghayyeh KHATAMI

    2015-06-01

    Full Text Available This study was performed to investigate the effect of drought stress and priming on germination of corn seeds (cultivar SC704 as a factorial experiment based on completely randomized design with three replications. Treatments were drought stress in four levels including 0,-3,-6 and -9 bar and priming as control, hydro, osmo, vitamin and hormone priming. Results showed that interaction of two factors was significant on radicle and plumule dry weight, seedling vigor and germination rate. Osmo-priming remained the radicle dry weight and seedling vigor index same to control but germination rate decreased in this treatment about 38% to control. Drought stress at any severity caused seed reservoirs were not use inefficiently. In conclusion, osmo and hormone primings were the best treatments for seed invigoration under severe drought stress.

  3. Peritraumatic and Trait Dissociation Differentiate Police Officers With Resilient Versus Symptomatic Trajectories of Posttraumatic Stress Symptoms

    OpenAIRE

    Isaac R. Galatzer-Levy; Madan, Anita; Neylan, Thomas C.; Henn-Haase, Clare; Marmar, Charles R.

    2011-01-01

    Research has consistently demonstrated that stress reactions to potentially traumatic events do not represent a unified phenomenon. Instead, individuals tend to cluster into prototypical response patterns over time including chronic symptoms, recovery, and resilience. We examined heterogeneity in a posttraumatic stress disorder (PTSD) symptom course in a sample of 178 active-duty police officers following exposure to a life-threatening event using latent growth mixture modeling (LGMM). This a...

  4. Association mapping of fruit, seed and disease resistance traits in Theobroma cacao L

    Science.gov (United States)

    An association mapping approach was employed to find markers for color, size, girth and mass of fruits; seed number and butterfat content; and resistance to black pod and witches’ broom diseases in cacao (Theobroma cacao L.). Ninety-five microsatellites (SSRs) and 775 single nucleotide polymorphisms...

  5. Quantitative trait loci for resistance to two fungal pathogens in Quercus robur

    Science.gov (United States)

    Cécile Robin; Amira Mougou-Hamdane; Jean-Marc Gion; Antoine Kremer; Marie-Laure. Desprez-Loustau

    2012-01-01

    Powdery mildew, caused by Erysiphe alphitoides (Ascomycete), is the most frequent disease of oaks, which are also known to be host plants for Phytophthora cinnamomi (Oomycete), the causal agent of ink disease. Components of genetic resistance to these two pathogens, infecting either leaves or root and collar, were...

  6. Quantitative trait loci associated with resistance to powdery mildew in cornus florida

    Science.gov (United States)

    Powdery mildew of flowering dogwood (Cornus florida) caused by Erysiphe pulchra is one of the most destructive diseases in nursery production of flowering dogwood throughout the southeastern U.S. Since the mid-1990s, efforts to breed for resistance to the disease have been undertaken, but to-date on...

  7. Ecological differentiation in xylem cavitation resistance is associated with stem and leaf structural traits

    NARCIS (Netherlands)

    Markesteijn, L.; Poorter, L.; Paz, H.; Sack, L.; Bongers, F.

    2011-01-01

    Cavitation resistance is a critical determinant of drought tolerance in tropical tree species, but little is known of its association with life history strategies, particularly for seasonal dry forests, a system critically driven by variation in water availability. We analysed vulnerability curves

  8. Release of pea germplasm with Fusarium resistance combined with desirable yield and anti-lodging traits

    Science.gov (United States)

    Fusarium root rot caused by Fusarium solani f. sp. pisi (Fsp) and Fusarium wilt caused by Fusarium oxysporum f. sp. pisi (Fop) races 1, 2 and 5, negatively impact the pea industry worldwide. Limited pea germplasm with agronomically acceptable characteristics combined with resistance to these disease...

  9. Quantitative trait loci for resistance to fish pasteurellosis in gilthead sea bream (Sparus aurata)

    NARCIS (Netherlands)

    Massault, C.; Franch, R.; Haley, C.; Koning, de D.J.; Bovenhuis, H.; Pellizzari, C.; Patarnello, T.; Bargelloni, L.

    2011-01-01

    Fish pasteurellosis is a bacterial disease causing important losses in farmed fish, including gilthead sea bream, a teleost fish of great relevance in marine aquaculture. We report in this study a QTL analysis for resistance to fish pasteurellosis in this species. An experimental population of 500

  10. Effect of T-stress on the cleavage crack growth resistance resulting from plastic flow

    DEFF Research Database (Denmark)

    Tvergaard, Viggo

    1998-01-01

    , the materials show crack growth resistance. It is shown here that the resistance is strongly dependent on the value of the non-singular T-stress, acting parallel to the crack plane. The numerical technique employed makes use of a thin dislocation-free strip of elastic material inside which the crack propagates...

  11. Aging related ER stress is not responsible for anabolic resistance in mouse skeletal muscle

    NARCIS (Netherlands)

    Chalil, S.; Pierre, N.; Bakker, A.D.; Manders, R.J.; Pletsers, A.; Francaux, M.; Klein-Nulend, J.; Jaspers, R.T.; Deldique, L.

    2015-01-01

    Anabolic resistance reflects the inability of skeletal muscle to maintain protein mass by appropriate stimulation of protein synthesis. We hypothesized that endoplasmic reticulum (ER) stress contributes to anabolic resistance in skeletal muscle with aging. Muscles were isolated from adult (8 mo) and

  12. Searching for plant root traits to improve soil cohesion and resist soil erosion

    Science.gov (United States)

    De Baets, Sarah; Smyth, Kevin; Denbigh, Tom; Weldon, Laura; Higgins, Ben; Matyjaszkiewicz, Antoni; Meersmans, Jeroen; Chenchiah, Isaac; Liverpool, Tannie; Quine, Tim; Grierson, Claire

    2017-04-01

    Soil erosion poses a serious threat to future food and environmental security. Soil erosion protection measures are therefore of great importance for soil conservation and food security. Plant roots have proven to be very effective in stabilizing the soil and protecting the soil against erosion. However, no clear insights are yet obtained into the root traits that are responsible for root-soil cohesion. This is important in order to better select the best species for soil protection. Research using Arabidopsis mutants has made great progress towards explaining how root systems are generated by growth, branching, and responses to gravity, producing mutants that affect root traits. In this study, the performance of selected Arabidopsis mutants is analyzed in three root-soil cohesion assays. Measurements of detachment, uprooting force and soil detachment are here combined with the microscopic analysis of root properties, such as the presence, length and density of root hairs in this case. We found that Arabidopsis seedlings with root hairs (wild type, wer myb23, rsl4) were more difficult to detach from gel media than hairless (cpc try) or short haired (rsl4, rhd2) roots. Hairy roots (wild type, wer myb23) on mature, non-reproductive rosettes were more difficult to uproot from compost or clay soil than hairless roots (cpc try). At high root densities, erosion rates from soils with hairless roots (cpc try) were as much as 10 times those seen from soils occupied by roots with hairs (wer myb23, wild type). We find therefore root hairs play a significant role in root-soil cohesion and in minimizing erosion. This framework and associated suite of experimental assays demonstrates its ability to measure the effect of any root phenotype on the effectiveness of plant roots in binding substrates and reducing erosion.

  13. Some Root Traits of Barley (Hordeum vulgare L. as Affected by Mycorrhizal Symbiosis under Drought Stress

    Directory of Open Access Journals (Sweden)

    R. Bayani

    2016-05-01

    Full Text Available The effect of drought stress and mycorrhizal symbiosis on the colonization, root and leaf phosphorous content, root and leaf phosphatase activity, root volume and area as well as shoot dry weight of a variety of hulless barley were evaluated using a completely randomized experimental design (CRD with 3 replications. Treatments were three levels of drought stress of 30, 60 and 90% field capacity and two levels of mycorrhizal with and without inoculation. According to the results, the highest value of leaf phosphorous (1.54 mg/g was observed at mycorrhizal symbiosis against severe drought treatment. Root phosphatase activity was highest (297.9 OD min -1 FW-1 at severe drought stress with mycorrhizal symbiosis which in comparison with mild stress in the presence of mycorrhiza showed 16.6 fold increasing. The control and non-mycorrhizal symbiosis treatments had highest root dry weight (0.091 g. The lowest root volume (0.016 cm2 observed at mycorrhizal symbiosis × severe drought treatment. Generally, Inoculation of barley seed with mycorrhiza at severe water stress could transport more phosphorous to shoot, especially leaf via inducing of leaf and root phosphatase activity. Also, in addition to supply of nutrient sources especially phosphorous for plant, mycorrhizal symbiosis could play an important role in withstanding water stress in plant via increasing of root dry weight and area.

  14. Effects of astaxanthin and emodin on the growth, stress resistance and disease resistance of yellow catfish (Pelteobagrus fulvidraco).

    Science.gov (United States)

    Liu, Fei; Shi, Hong-Zhuan; Guo, Qiao-Sheng; Yu, Ye-Bing; Wang, Ai-Ming; Lv, Fu; Shen, Wen-Biao

    2016-04-01

    Yellow catfish (Pelteobagrus fulvidraco) has become a commercially important fish species in China and eastern Asia. High-density aquaculture has led to congestion and excessive stress and contributed to bacterial infection outbreaks that have caused high mortality. We investigated the effects of dietary supplementation with astaxanthin and emodin alone and in combination on the growth and stress resistance of yellow catfish. After 60 days of feeding, each group of fish (control, astaxanthin, emodin, and astaxanthin plus emodin (combination) groups) was exposed to acute crowding stress for 24 h, and a subsample of fish from the four groups was challenged with the bacterial septicemia pathogen Proteus mirabilis after the end of the crowding stress experiment. Compared with the control, the astaxanthin and emodin groups showed increases in serum total protein (TP), hepatic superoxide dismutase (SOD) activity and hepatic heat shock proteins 70 (HSP70) mRNA levels at 12 and 24 h after the initiation of crowding stress. The combination group exhibited increases in alanine aminotransferase (ALT) activity, aspartate aminotransferase (AST) activity, serum TP, hepatic SOD activity and hepatic HSP70 mRNA levels within 24 h after the initiation of crowding stress. However, decreases relative to the control were observed in the serum cortisol and glucose contents in the three treatment groups at 12 and 24 h after the initiation of crowding stress, in ALT and AST activity in the astaxanthin and emodin group at 24 h after the initiation of crowding stress, and in the serum lysozyme activity, serum alkaline phosphatase (ALP) activity, and hepatic catalase (CAT) and malondialdehyde (MDA) activity in the combination group at 24 h after the initiation of crowding stress. Additionally, the cumulative mortality after P. mirabilis infection was lower in all three treatment groups (57.00%-70.33%) than in the control (77.67%). Dietary supplementation with astaxanthin and emodin decreased

  15. Genotyping-by-sequencing markers facilitate the identification of quantitative trait loci controlling resistance to Penicillium expansum in Malus sieversii

    Science.gov (United States)

    Wisniewski, Michael; Fazio, Gennaro; Burchard, Erik; Gutierrez, Benjamin; Levin, Elena; Droby, Samir

    2017-01-01

    Blue mold caused by Penicillium expansum is the most important postharvest disease of apple worldwide and results in significant financial losses. There are no defined sources of resistance to blue mold in domesticated apple. However, resistance has been described in wild Malus sieversii accessions, including plant introduction (PI)613981. The objective of the present study was to identify the genetic loci controlling resistance to blue mold in this accession. We describe the first quantitative trait loci (QTL) reported in the Rosaceae tribe Maleae conditioning resistance to P. expansum on genetic linkage group 3 (qM-Pe3.1) and linkage group 10 (qM-Pe10.1). These loci were identified in a M.× domestica ‘Royal Gala’ X M. sieversii PI613981 family (GMAL4593) based on blue mold lesion diameter seven days post-inoculation in mature, wounded apple fruit inoculated with P. expansum. Phenotypic analyses were conducted in 169 progeny over a four year period. PI613981 was the source of the resistance allele for qM-Pe3.1, a QTL with a major effect on blue mold resistance, accounting for 27.5% of the experimental variability. The QTL mapped from 67.3 to 74 cM on linkage group 3 of the GMAL4593 genetic linkage map. qM-Pe10.1 mapped from 73.6 to 81.8 cM on linkage group 10. It had less of an effect on resistance, accounting for 14% of the experimental variation. ‘Royal Gala’ was the primary contributor to the resistance effect of this QTL. However, resistance-associated alleles in both parents appeared to contribute to the least square mean blue mold lesion diameter in an additive manner at qM-Pe10.1. A GMAL4593 genetic linkage map composed of simple sequence repeats and ‘Golden Delicious’ single nucleotide polymorphism markers was able to detect qM-Pe10.1, but failed to detect qM-Pe3.1. The subsequent addition of genotyping-by-sequencing markers to the linkage map provided better coverage of the PI613981 genome on linkage group 3 and facilitated discovery of q

  16. Genotyping-by-sequencing markers facilitate the identification of quantitative trait loci controlling resistance to Penicillium expansum in Malus sieversii.

    Directory of Open Access Journals (Sweden)

    John L Norelli

    Full Text Available Blue mold caused by Penicillium expansum is the most important postharvest disease of apple worldwide and results in significant financial losses. There are no defined sources of resistance to blue mold in domesticated apple. However, resistance has been described in wild Malus sieversii accessions, including plant introduction (PI613981. The objective of the present study was to identify the genetic loci controlling resistance to blue mold in this accession. We describe the first quantitative trait loci (QTL reported in the Rosaceae tribe Maleae conditioning resistance to P. expansum on genetic linkage group 3 (qM-Pe3.1 and linkage group 10 (qM-Pe10.1. These loci were identified in a M.× domestica 'Royal Gala' X M. sieversii PI613981 family (GMAL4593 based on blue mold lesion diameter seven days post-inoculation in mature, wounded apple fruit inoculated with P. expansum. Phenotypic analyses were conducted in 169 progeny over a four year period. PI613981 was the source of the resistance allele for qM-Pe3.1, a QTL with a major effect on blue mold resistance, accounting for 27.5% of the experimental variability. The QTL mapped from 67.3 to 74 cM on linkage group 3 of the GMAL4593 genetic linkage map. qM-Pe10.1 mapped from 73.6 to 81.8 cM on linkage group 10. It had less of an effect on resistance, accounting for 14% of the experimental variation. 'Royal Gala' was the primary contributor to the resistance effect of this QTL. However, resistance-associated alleles in both parents appeared to contribute to the least square mean blue mold lesion diameter in an additive manner at qM-Pe10.1. A GMAL4593 genetic linkage map composed of simple sequence repeats and 'Golden Delicious' single nucleotide polymorphism markers was able to detect qM-Pe10.1, but failed to detect qM-Pe3.1. The subsequent addition of genotyping-by-sequencing markers to the linkage map provided better coverage of the PI613981 genome on linkage group 3 and facilitated discovery of q

  17. Genotyping-by-sequencing markers facilitate the identification of quantitative trait loci controlling resistance to Penicillium expansum in Malus sieversii.

    Science.gov (United States)

    Norelli, John L; Wisniewski, Michael; Fazio, Gennaro; Burchard, Erik; Gutierrez, Benjamin; Levin, Elena; Droby, Samir

    2017-01-01

    Blue mold caused by Penicillium expansum is the most important postharvest disease of apple worldwide and results in significant financial losses. There are no defined sources of resistance to blue mold in domesticated apple. However, resistance has been described in wild Malus sieversii accessions, including plant introduction (PI)613981. The objective of the present study was to identify the genetic loci controlling resistance to blue mold in this accession. We describe the first quantitative trait loci (QTL) reported in the Rosaceae tribe Maleae conditioning resistance to P. expansum on genetic linkage group 3 (qM-Pe3.1) and linkage group 10 (qM-Pe10.1). These loci were identified in a M.× domestica 'Royal Gala' X M. sieversii PI613981 family (GMAL4593) based on blue mold lesion diameter seven days post-inoculation in mature, wounded apple fruit inoculated with P. expansum. Phenotypic analyses were conducted in 169 progeny over a four year period. PI613981 was the source of the resistance allele for qM-Pe3.1, a QTL with a major effect on blue mold resistance, accounting for 27.5% of the experimental variability. The QTL mapped from 67.3 to 74 cM on linkage group 3 of the GMAL4593 genetic linkage map. qM-Pe10.1 mapped from 73.6 to 81.8 cM on linkage group 10. It had less of an effect on resistance, accounting for 14% of the experimental variation. 'Royal Gala' was the primary contributor to the resistance effect of this QTL. However, resistance-associated alleles in both parents appeared to contribute to the least square mean blue mold lesion diameter in an additive manner at qM-Pe10.1. A GMAL4593 genetic linkage map composed of simple sequence repeats and 'Golden Delicious' single nucleotide polymorphism markers was able to detect qM-Pe10.1, but failed to detect qM-Pe3.1. The subsequent addition of genotyping-by-sequencing markers to the linkage map provided better coverage of the PI613981 genome on linkage group 3 and facilitated discovery of qM-Pe3.1. A DNA

  18. Crop resistance traits modify the effects of an aboveground herbivore, brown planthopper, on soil microbial biomass and nematode community via changes to plant performance.

    NARCIS (Netherlands)

    Huang, J.; Liu, M.; Chen, F.; Griffiths, B.S.; Chen, X.; Johnson, S.N.; Hu, F.

    2012-01-01

    Plant-mediated effects of aboveground herbivory on the belowground ecosystem are well documented, but less attention has been paid to agro-ecosystems and in particular how crop cultivars with different traits (i.e. resistance to pests) shape such interactions. A fully factorial experiment was

  19. Common trade-offs between xylem resistance to cavitation and other physiological traits do not hold among unrelated Populus deltoides x Populus nigra hybrids.

    Science.gov (United States)

    Fichot, Régis; Barigah, Têtè S; Chamaillard, Sylvain; LE Thiec, Dider; Laurans, Françoise; Cochard, Hervé; Brignolas, Franck

    2010-09-01

    We examined the relationships between xylem resistance to cavitation and 16 structural and functional traits across eight unrelated Populus deltoides x Populus nigra genotypes grown under two contrasting water regimes. The xylem water potential inducing 50% loss of hydraulic conductance (Psi(50)) varied from -1.60 to -2.40 MPa. Drought-acclimated trees displayed a safer xylem, although the extent of the response was largely genotype dependent, with Psi(50) being decreased by as far as 0.60 MPa. At the tissue level, there was no clear relationship between xylem safety and either xylem water transport efficiency or xylem biomechanics; the only structural trait to be strongly associated with Psi(50) was the double vessel wall thickness, genotypes exhibiting a thicker double wall being more resistant. At the leaf level, increased cavitation resistance was associated with decreased stomatal conductance, while no relationship could be identified with traits associated with carbon uptake or bulk leaf carbon isotope discrimination, a surrogate of intrinsic water-use efficiency. At the whole-plant level, increased safety was associated with higher shoot growth potential under well-irrigated regime only. We conclude that common trade-offs between xylem resistance to cavitation and other physiological traits that are observed across species may not necessarily hold true at narrower scales.

  20. Plant community resistance to invasion by Bromus species: The roles of community attributes, Bromus interactions with plant communities, and Bromus traits [Chapter 10

    Science.gov (United States)

    Jeanne C. Chambers; Matthew J. Germino; Jayne Belnap; Cynthia S. Brown; Eugene W. Schupp; Samuel B. St. Clair

    2016-01-01

    The factors that determine plant community resistance to exotic annual Bromus species (Bromus hereafter) are diverse and context specific. They are influenced by the environmental characteristics and attributes of the community, the traits of Bromus species, and the direct and indirect interactions of Bromus with the plant community. Environmental factors, in...

  1. Implications of stress-induced genetic variation for minimizing multidrug resistance in bacteria

    Directory of Open Access Journals (Sweden)

    Obolski Uri

    2012-08-01

    Full Text Available Abstract Background Antibiotic resistance in bacterial infections is a growing threat to public health. Recent evidence shows that when exposed to stressful conditions, some bacteria perform higher rates of horizontal gene transfer and mutation, and thus acquire antibiotic resistance more rapidly. Methods We incorporate this new notion into a mathematical model for the emergence of antibiotic multi-resistance in a hospital setting. Results We show that when stress has a considerable effect on genetic variation, the emergence of antibiotic resistance is dramatically affected. A strategy in which patients receive a combination of antibiotics (combining is expected to facilitate the emergence of multi-resistant bacteria when genetic variation is stress-induced. The preference between a strategy in which one of two effective drugs is assigned randomly to each patient (mixing, and a strategy where only one drug is administered for a specific period of time (cycling is determined by the resistance acquisition mechanisms. We discuss several features of the mechanisms by which stress affects variation and predict the conditions for success of different antibiotic treatment strategies. Conclusions These findings should encourage research on the mechanisms of stress-induced genetic variation and establish the importance of incorporating data about these mechanisms when considering antibiotic treatment strategies.

  2. Torsional stress and resistance of concrte member. Concrete buzai no nejiri oryoku to tairyoku

    Energy Technology Data Exchange (ETDEWEB)

    Saeki, N. (Hokkaido University, Sapporo (Japan). Faculty of Engineering)

    1991-09-01

    Torsional stress and resistance are discussed for designing concrete members. A hypothesis was given that, in the simple torsion elasticity theory, the axial displacement is freely variable and no stress is created. In spherical and cylindrical cross section, no axial deformation will occur, but a displacement can occur in rectangular cross section. The general torsion elasticity theory can be applied also to a case where an axial stress is created. A discussion was also given to the plasticity theory in which shear stress enters the plastic region. A plain concrete is destructed at the same time as cracks develop, hence it reaches its resistance limit when the calculated value for a tensile stress caused from a torsional stress exceeds its tensile strength. Torsional resistance of a reinforced concrete after cracks have developed is calculated generally by the space truss theory, wherein the torsional load is thought shared in the lateral reinforcing bars, axial reinforcing bars, and diagonal concrete members. The pure torsion or torsion-pure bending resistance may be calculated theoretically, but the combined torsion-bending resistance is sought generally based on correlative curves derived from experiments. 25 refs., 14 figs., 2 tabs.

  3. Environmental maternal effects mediate the resistance of maritime pine to biotic stress.

    Directory of Open Access Journals (Sweden)

    María Vivas

    Full Text Available The resistance to abiotic stress is increasingly recognised as being impacted by maternal effects, given that environmental conditions experienced by parent (mother trees affect stress tolerance in offspring. We hypothesised that abiotic environmental maternal effects may also mediate the resistance of trees to biotic stress. The influence of maternal environment and maternal genotype and the interaction of these two factors on early resistance of Pinus pinaster half-sibs to the Fusarium circinatum pathogen was studied using 10 mother genotypes clonally replicated in two contrasting environments. Necrosis length of infected seedlings was 16% shorter in seedlings grown from favourable maternal environment seeds than in seedlings grown from unfavourable maternal environment seeds. Damage caused by F. circinatum was mediated by maternal environment and maternal genotype, but not by seed mass. Mechanisms unrelated to seed provisioning, perhaps of epigenetic nature, were probably involved in the transgenerational plasticity of P. pinaster, mediating its resistance to biotic stress. Our findings suggest that the transgenerational resistance of pines due to an abiotic stress may interact with the defensive response of pines to a biotic stress.

  4. Evaluation of Diversity and Traits Correlation in Spring Wheat Cultivars under Drought Stress

    Directory of Open Access Journals (Sweden)

    Mohammad Reza NAGHAVI

    2015-09-01

    Full Text Available In order to study of diversity and classify agro-morphological characters under normal irrigation and drought stress in spring wheat cultivars, 20 cultivars were evaluated in the research farm of University of Tabriz, Iran. According to the results, significant correlation was found between grain yield and number of spikes per plant, number of tiller per plant, number of fertile tillers, spike length, root length, root number, root volume, root diameter and root dry weight under both conditions. Moreover, 1,000 grain weight and plant dry weight had significant positive correlation with grain yield under drought stress. Factor analysis detected four and two factors which explained 96.77% and 90.59% of the total variation in normal irrigation and drought stress conditions, respectively. In drought stress condition the first factor justified 69.52% of total variation and was identified as yield factor. The second factor explained 21.07% of total variation and represented the biomass and plant height factor. Cluster analysis was based on the four and two factors obtained. According to the amount of factors for clusters obtained under drought stress, ‘Kavir’, ‘Niknejhad’, ‘Moghan 3’, ‘Darya’ and ‘Marvdasht’ were identified as the most drought tolerant cultivars. Other cluster was comprised of ‘Bahar’, ‘Pishtaz’, ‘Bam’, ‘Sepahan’, ‘Sistan’, ‘Pars’ and ‘Sivand’ and was named as the most sensitive under drought stress. Tolerant cultivars identified within the study can be used for direct culture or as genitors in breeding programs.

  5. [Current status of operations in community general support centers and the correlation of personal traits, work environment and occupational stress].

    Science.gov (United States)

    Yamaguchi, Yoshie

    2010-01-01

    The purpose of this study was to identify the current status of operations at community general support centers which provide coordination for elderly care and the correlation of personal traits, work environment and the occupational stress of the staff. Subjects of the study were 251 staff members of community general support centers. The current status of operations at the community general support centers and the personal traits, work environment, effort-remuneration imbalance model (ERI) and general health questionnaire (GHQ) were surveyed. The initial analysis involved a comparison by a chi-square test on: The effort-remuneration ratio (E/R ratio) of personal traits and work environment, risk of over-commitment (OC), and GHQ score. To explore the correlation between the E/R ratio of the three GHQ groups (low, middle and high score groups) and the OC value, one-way analysis of variance was performed. Out of the four basic functions of the community general support centers, 22.0% of the respondents noted that "establishment of a regional, comprehensive/multi-tiered service network" was functioning, and 50.4% of respondents noted that "comprehensive and continuous care management" was functioning. The average effort score was 15.5 +/- 5.3, approximately double the average value of preceding studies. Significant differences found in GHQ scores were related to working hours (pworking hours of 50 h or more" (OR: 10.38, 95% CI: 2.52-42.70), "Unstable employment" (OR: 2.75, 95% CI: 1.22-6.21) and "Anxiety related to task content" (OR: 17.04, 95% CI: 3.57-81.24). Items observed to have significant correlation with OC value risk factors were: "Weekly working hours of 50 h or more" (OR: 8.04, 95% CI: 1.99-32.41) and "Anxiety related to task content" (OR: 4.60, 95% CI: 2.04-10.37). We conclude that the basic functions of the community general support centers are not presently very functional. The stress levels of the community general support center staff are high and

  6. Trait performance correlations across life stages under environmental stress conditions in the common frog, Rana temporaria.

    Directory of Open Access Journals (Sweden)

    Frank Johansson

    Full Text Available If an organism's juvenile and adult life stages inhabit different environments, certain traits may need to be independently adapted to each environment. In many organisms, a move to a different environment during ontogeny is accompanied by metamorphosis. In such organisms phenotypic induction early in ontogeny can affect later phenotypes. In laboratory experiments we first investigated correlations between body morphology and the locomotor performance traits expressed in different life stages of the common frog, Rana temporaria: swimming speed and acceleration in tadpoles; and jump-distance in froglets. We then tested for correlations between these performances across life stages. We also subjected tadpoles to unchanging or decreasing water levels to explore whether decreasing water levels might induce any carry-over effects. Body morphology and performance were correlated in tadpoles; morphology and performance were correlated in froglets: hence body shape and morphology affect performance within each life stage. However, performance was decoupled across life stages, as there was no correlation between performance in tadpoles and performance in froglets. While size did not influence tadpole performance, it was correlated with performance of the metamorphosed froglets. Experiencing decreasing water levels accelerated development time, which resulted in smaller tadpoles and froglets, i.e., a carry-over effect. Interestingly, decreasing water levels positively affected the performance of tadpoles, but negatively affected froglet performance. Our results suggest that performance does not necessarily have to be correlated between life stages. However, froglet performance is size dependent and carried over from the tadpole stage, suggesting that some important size-dependent characters cannot be decoupled via metamorphosis.

  7. An examination of personality, emotional intelligence, coping, gender and subjective well-being with perceived stress (trait and state) in undergraduate students.

    OpenAIRE

    Osborne, Shona Elizabeth

    2009-01-01

    This multivariate study aimed to further understand student stress. Associations between personality, emotional intelligence, coping and subjective well-being with perceived stress (trait and state) were examined in 238 undergraduate students, using self-report measures. Gender differences in these variables were also investigated. The results showed that students low in emotional stability, extraversion, emotional intelligence, subjective well-being and those with a tendency to use emotion...

  8. The Big Five personality and temperamental traits and its correlation with styles of coping with stress in the fire brigade officers

    Directory of Open Access Journals (Sweden)

    Justyna Szrajda

    2017-09-01

    Full Text Available Selecting specific professional activities (e.g. a brigade officer and methods for coping with difficult situations may result from personal predispositions of a given person. Personality is founded on the innate temperament. The way of dealing with stress depends on personality traits whose influence is manifested, amongst other things, in the selection of specific coping styles. The current study aim to examine the level of correlation between personality and temperamental traits with manifested coping styles. The study covered 58 volunteers – male fire brigade officers. The following tools were used: Personality Inventory, NEO-FFI, Formal Characteristics of Behaviour: Temperament Inventory – Revised Version, FCZ-KT (R and Coping Inventory for Stressful Situations, CISS. Emotion-focused coping style for stressful situations correlates with the following traits: positively, with perseveration (r=0.5115 and with emotional reactivity (r=0.4927, and negatively, with briskness (r=-0.3926 and endurance (r=-0.5408. The task-oriented coping style for stressful situations correlates positively with extraversion (r=0.3236 and conscientiousness (r=0.3088, and negatively with neuroticism (r=-0.3368 in the NEO-FFI. The emotion-focused coping style for stressful situations is positively correlated with neuroticism (NEO-FFI (r=0.4150. In fire brigade officers, As far as personality traits were concerned, fire brigade officers scored relatively high in extraversion, conscientiousness and low in neuroticism and were likely to demonstrate the task-oriented coping style for stressful situations. Lower level of perseveration and high level of briskness and endurance were associated with emotion-focused coping style for stressful situations. Similarly, the tendency to focus on emotions experienced in stressful situations were associated with high level of neuroticism in the study group.

  9. THE STRESS RESISTANCE OF STUDENTS. THE PARADIGM OF SUBJECT PERSONALITY SELF- ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Sergey I. Dyakov

    2016-01-01

    Full Text Available The aim of the investigation is to consider a problem of stress resistance of students in the context of subject self-organization of the personality. Methods. The following methods of research are used: questioning; psychological and diagnostic tests «Tolerance of Uncertainty» (NTN and «Personal Factors of Decisions» (PFD by T. V. Kornilova; original experimental experiences – «Coding», a technique of a self-assessment (scaling and «A locus control». While data processing the methods of mathematical statistics (SPSS 12 package – the correlation analysis of Pearson and the factorial analysis with rotation use a component by «verimax» method are applied. Results and scientific novelty. Types of subjectivity and strategy of stress resistance are allocated. The nature and a role of the emotional and stressful mechanism having information and semantic properties in its basis are disclosed. Communication of irresponsible mechanisms of mentality with the sphere of consciousness in the context of subjectivity of the personality is shown. Mechanisms of emotional and rational self-control of system of mental self-organization of the person are presented. The statistical and qualitative data opening communications between properties of subjectivity and stress resistance of the personality are empirically obtained. Variation of the relations and also types of subjectivity and stress resistance emphasized based on the results of the presented research. Original (author’s methods of studying of subjectivity and factors of stress resistance are presented. Practical significance. The revealed factors of subject self-organization reveal the stress-producing directions of the environment and the relation of the personality to situations of changes and uncertainty: and also indicate subject properties of resistance to stress which need to be developed to increase the level of health of students, to reduce risk of deviance and delinquency of

  10. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Science.gov (United States)

    Pittman, Joseph R.; Kline, La’Kesha C.; Kenyon, William J.

    2015-01-01

    The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation) is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance). To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C), low pH (pH 2.8), and oxidative stress (15 mM H2O2). In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth. PMID:27682115

  11. Towards positional isolation of three quantitative trait loci conferring resistance to powdery mildew in two Spanish barley landraces.

    Directory of Open Access Journals (Sweden)

    Cristina Silvar

    Full Text Available Three quantitative trait loci (QTL conferring broad spectrum resistance to powdery mildew, caused by the fungus Blumeria graminis f. sp. hordei, were previously identified on chromosomes 7HS, 7HL and 6HL in the Spanish barley landrace-derived lines SBCC097 and SBCC145. In the present work, a genome-wide putative linear gene index of barley (Genome Zipper and the first draft of the physical, genetic and functional sequence of the barley genome were used to go one step further in the shortening and explicit demarcation on the barley genome of these regions conferring resistance to powdery mildew as well as in the identification of candidate genes. First, a comparative analysis of the target regions to the barley Genome Zippers of chromosomes 7H and 6H allowed the development of 25 new gene-based molecular markers, which slightly better delimit the QTL intervals. These new markers provided the framework for anchoring of genetic and physical maps, figuring out the outline of the barley genome at the target regions in SBCC097 and SBCC145. The outermost flanking markers of QTLs on 7HS, 7HL and 6HL defined a physical area of 4 Mb, 3.7 Mb and 3.2 Mb, respectively. In total, 21, 10 and 16 genes on 7HS, 7HL and 6HL, respectively, could be interpreted as potential candidates to explain the resistance to powdery mildew, as they encode proteins of related functions with respect to the known pathogen defense-related processes. The majority of these were annotated as belonging to the NBS-LRR class or protein kinase family.

  12. Towards positional isolation of three quantitative trait loci conferring resistance to powdery mildew in two Spanish barley landraces.

    Science.gov (United States)

    Silvar, Cristina; Perovic, Dragan; Nussbaumer, Thomas; Spannagl, Manuel; Usadel, Björn; Casas, Ana; Igartua, Ernesto; Ordon, Frank

    2013-01-01

    Three quantitative trait loci (QTL) conferring broad spectrum resistance to powdery mildew, caused by the fungus Blumeria graminis f. sp. hordei, were previously identified on chromosomes 7HS, 7HL and 6HL in the Spanish barley landrace-derived lines SBCC097 and SBCC145. In the present work, a genome-wide putative linear gene index of barley (Genome Zipper) and the first draft of the physical, genetic and functional sequence of the barley genome were used to go one step further in the shortening and explicit demarcation on the barley genome of these regions conferring resistance to powdery mildew as well as in the identification of candidate genes. First, a comparative analysis of the target regions to the barley Genome Zippers of chromosomes 7H and 6H allowed the development of 25 new gene-based molecular markers, which slightly better delimit the QTL intervals. These new markers provided the framework for anchoring of genetic and physical maps, figuring out the outline of the barley genome at the target regions in SBCC097 and SBCC145. The outermost flanking markers of QTLs on 7HS, 7HL and 6HL defined a physical area of 4 Mb, 3.7 Mb and 3.2 Mb, respectively. In total, 21, 10 and 16 genes on 7HS, 7HL and 6HL, respectively, could be interpreted as potential candidates to explain the resistance to powdery mildew, as they encode proteins of related functions with respect to the known pathogen defense-related processes. The majority of these were annotated as belonging to the NBS-LRR class or protein kinase family.

  13. Transgenic Sugarcane with a cry1Ac Gene Exhibited Better Phenotypic Traits and Enhanced Resistance against Sugarcane Borer.

    Directory of Open Access Journals (Sweden)

    Shiwu Gao

    Full Text Available We developed sugarcane plants with improved resistance to the sugarcane borer, Diatraea saccharalis (F. An expression vector pGcry1Ac0229, harboring the cry1Ac gene and the selectable marker gene, bar, was constructed. This construct was introduced into the sugarcane cultivar FN15 by particle bombardment. Transformed plantlets were identified after selection with Phosphinothricin (PPT and Basta. Plantlets were then screened by PCR based on the presence of cry1Ac and 14 cry1Ac positive plantlets were identified. Real-time quantitative PCR (RT-qPCR revealed that the copy number of cry1Ac gene in the transgenic lines varied from 1 to 148. ELISA analysis showed that Cry1Ac protein levels in 7 transgenic lines ranged from 0.85 μg/FWg to 70.92 μg/FWg in leaves and 0.04 μg/FWg to 7.22 μg/FWg in stems, and negatively correlated to the rate of insect damage that ranged from 36.67% to 13.33%, respectively. Agronomic traits of six transgenic sugarcane lines with medium copy numbers were similar to the non-transgenic parental line. However, phenotype was poor in lines with high or low copy numbers. Compared to the non-transgenic control plants, all transgenic lines with medium copy numbers had relatively equal or lower sucrose yield and significantly improved sugarcane borer resistance, which lowered susceptibility to damage by insects. This suggests that the transgenic sugarcane lines harboring medium copy numbers of the cry1Ac gene may have significantly higher resistance to sugarcane borer but the sugarcane yield in these lines is similar to the non-transgenic control thus making them superior to the control lines.

  14. Gene-based Association Approach Identify Genes Across Stress Traits in Fruit Flies

    DEFF Research Database (Denmark)

    Rohde, Palle Duun; Edwards, Stefan McKinnon; Sarup, Pernille Merete

    approach grouping variants accordingly to gene position, thus lowering the number of statistical tests performed and increasing the probability of identifying genes with small to moderate effects. Using this approach we identify numerous genes associated with different types of stresses in Drosophila...

  15. Heat stress in wheat (Triticum aestivum L.) : Effects on grain growth and quality traits

    NARCIS (Netherlands)

    Spiertz, J.H.J.; Hamer, R.J.; Xu, H.; Primo Martin, C.; Don, C.; Putten, van der P.E.L.

    2006-01-01

    Heat stress effects on grain dry mass and quality were studied in spring wheat genotypes (Triticum aestivum L.). Three cultivars were chosen with respect to heat tolerance: Lavett (genotype 1), selected for temperate growing conditions and two CIMMYT cultivars, Ciano-79 (genotype 2) and Attila

  16. Heat stress in wheat (Triticum aestivum L.): Effects on grain growth and quality traits

    NARCIS (Netherlands)

    Spiertz, J.H.J.; Hamer, R.J.; Xu, H.; Primo-Martin, C.; Don, C.; Putten, P.E.L. van der

    2006-01-01

    Heat stress effects on grain dry mass and quality were studied in spring wheat genotypes (Triticum aestivum L.). Three cultivars were chosen with respect to heat tolerance: Lavett (genotype 1), selected for temperate growing conditions and two CIMMYT cultivars, Ciano-79 (genotype 2) and Attila

  17. A comprehensive meta QTL analysis for fiber quality, yield, yield related and morphological traits, drought tolerance, and disease resistance in tetraploid cotton.

    Science.gov (United States)

    Said, Joseph I; Lin, Zhongxu; Zhang, Xianlong; Song, Mingzhou; Zhang, Jinfa

    2013-11-11

    The study of quantitative trait loci (QTL) in cotton (Gossypium spp.) is focused on traits of agricultural significance. Previous studies have identified a plethora of QTL attributed to fiber quality, disease and pest resistance, branch number, seed quality and yield and yield related traits, drought tolerance, and morphological traits. However, results among these studies differed due to the use of different genetic populations, markers and marker densities, and testing environments. Since two previous meta-QTL analyses were performed on fiber traits, a number of papers on QTL mapping of fiber quality, yield traits, morphological traits, and disease resistance have been published. To obtain a better insight into the genome-wide distribution of QTL and to identify consistent QTL for marker assisted breeding in cotton, an updated comparative QTL analysis is needed. In this study, a total of 1,223 QTL from 42 different QTL studies in Gossypium were surveyed and mapped using Biomercator V3 based on the Gossypium consensus map from the Cotton Marker Database. A meta-analysis was first performed using manual inference and confirmed by Biomercator V3 to identify possible QTL clusters and hotspots. QTL clusters are composed of QTL of various traits which are concentrated in a specific region on a chromosome, whereas hotspots are composed of only one trait type. QTL were not evenly distributed along the cotton genome and were concentrated in specific regions on each chromosome. QTL hotspots for fiber quality traits were found in the same regions as the clusters, indicating that clusters may also form hotspots. Putative QTL clusters were identified via meta-analysis and will be useful for breeding programs and future studies involving Gossypium QTL. The presence of QTL clusters and hotspots indicates consensus regions across cultivated tetraploid Gossypium species, environments, and populations which contain large numbers of QTL, and in some cases multiple QTL associated

  18. Detection of a quantitative trait locus associated with resistance to infection with Trichuris suis in pigs

    DEFF Research Database (Denmark)

    Skallerup, Per; Thamsborg, Stig Milan; Jørgensen, Claus Bøttcher

    2015-01-01

    that this region of SSC13 harboured genes with effects on T. suis burden by genotyping three SNPs within the putative QTL in unrelated pigs exposed to either experimental or natural T. suis infections and from which we had FEC (n=113) or worm counts (n=178). In these studies, two of the SNPs (rs55618716, ST) were...... associated with FEC (Pworm burden. In conclusion, our study demonstrates that genetic markers for resistance to T. suis as indicated by low FEC can be identified in pigs....

  19. Influence of stress on creep deformation properties of 9-12Cr ferritic creep resistant steels

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, K.; Sawada, K.; Kushima, H. [National Institute for Materials Science (Japan)

    2008-07-01

    Creep deformation property of 9-12Cr ferritic creep resistant steels was investigated. With decrease in stress, a magnitude of creep strain at the onset of accelerating creep stage decreased from about 2% in the short-term to less than 1% in the longterm. A time to 1% total strain was observed in the transient creep stage in the short term regime, however, it shifted to the accelerating creep stage in the long-term regime. Life fraction of the times to 1% creep strain and 1% total strain tended to increase with decrease in stress. Difference in stress dependence of the minimum creep rate was observed in the high- and low-stress regimes with a boundary condition of 50% of 0.2% offset yield stress. Stress dependence of the minimum creep rate in the high stress regime was equivalent to a strain rate dependence of the flow stress evaluated by tensile test, and a magnitude of stress exponent, n, in the high stress regime decreased with increase in temperature from 20 at 550 C to 10 at 700 C. On the other hand, n value in the low stress regime was about 5, and creep deformation in the low stress regime was considered to be controlled by dislocation climb. Creep rupture life was accurately predicted by a region splitting method by considering a change in stress dependence of creep deformation. (orig.)

  20. Big Five Personality Traits and the General Factor of Personality as Moderators of Stress and Coping Reactions Following an Emergency Alarm on a Swiss University Campus

    NARCIS (Netherlands)

    M.P. Hengartner (Michael P.); D. van der Linden (Dimitri); L. Bohleber (Laura); A. von Wyl (Agnes)

    2017-01-01

    textabstractWe conducted an online survey including 306 participants aged 18-64years to assess the general factor of personality (GFP) and Big Five personality traits in relation to individual stress and coping reactions following a shooting emergency alarm at a Swiss university campus. Although the

  1. Oxidative stress physiology in relation to life history traits of a free-living vertebrate : the spotted snow skink, Niveoscincus ocellatus

    NARCIS (Netherlands)

    Isaksson, Caroline; While, Geoffrey M.; Olsson, Mats; Komdeur, Jan; Wapstra, Erik

    Recent research suggests that oxidative stress, via its links to metabolism and senescence, is a key mechanism linking life history traits such as fecundity and growth with survival; however, this has rarely been put under empirical scrutiny within free-living populations. Using a wild population of

  2. Innate and introduced resistance traits in genetically modified aspen trees and their effect on leaf beetle feeding.

    Directory of Open Access Journals (Sweden)

    Joakim Hjältén

    Full Text Available Genetic modifications of trees may provide many benefits, e.g. increase production, and mitigate climate change and herbivore impacts on forests. However, genetic modifications sometimes result in unintended effects on innate traits involved in plant-herbivore interactions. The importance of intentional changes in plant defence relative to unintentional changes and the natural variation among clones used in forestry has not been evaluated. By a combination of biochemical measurements and bioassays we investigated if insect feeding on GM aspens is more affected by intentional (induction Bt toxins than of unintentional, non-target changes or clonal differences in innate plant defence. We used two hybrid wildtype clones (Populus tremula x P. tremuloides and Populus tremula x P. alba of aspen that have been genetically modified for 1 insect resistance (two Bt lines or 2 reduced lignin properties (two lines COMT and CAD, respectively. Our measurements of biochemical properties suggest that unintended changes by GM modifications (occurring due to events in the transformation process in innate plant defence (phenolic compounds were generally smaller but fundamentally different than differences seen among different wildtype clones (e.g. quantitative and qualitative, respectively. However, neither clonal differences between the two wildtype clones nor unintended changes in phytochemistry influenced consumption by the leaf beetle (Phratora vitellinae. By contrast, Bt induction had a strong direct intended effect as well as a post experiment effect on leaf beetle consumption. The latter suggested lasting reduction of beetle fitness following Bt exposure that is likely due to intestinal damage suffered by the initial Bt exposure. We conclude that Bt induction clearly have intended effects on a target species. Furthermore, the effect of unintended changes in innate plant defence traits, when they occur, are context dependent and have in comparison to Bt

  3. Impact of Laser Irradiation on Brain Resistance to Postresuscitative Emotional Stresses (Experimental Study

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2009-01-01

    Full Text Available The paper shows how to solve the urgent problem of posthypoxic rat brain resistance to emotional stress. An hour hypovolemic hypotension (mean blood pressure 45 mm Hg served as a model of a terminal condition. The integra-tive activity of the rat brain was evaluated by the elevated cross labyrinth test. Emotional stress was induced by confrontation between the falsely operated and antihypertensive rats within 30 postischemic days. Laser irradiation was carried out an hour after blood reinfusion. Laser irradiation used before emotional stress was shown to increase the resistance of the posthypoxic rat brain to emotional stress and to prevent the development of depression-like states in the late periods after resuscitation. Key words: blood loss, postresuscitative period, emotional stress, laser irradiation.

  4. Coupled stress-strain and electrical resistivity measurements on copper based shape memory single crystals

    Directory of Open Access Journals (Sweden)

    Gonzalez Cezar Henrique

    2004-01-01

    Full Text Available Recently, electrical resistivity (ER measurements have been done during some thermomechanical tests in copper based shape memory alloys (SMA's. In this work, single crystals of Cu-based SMA's have been studied at different temperatures to analyse the relationship between stress (s and ER changes as a function of the strain (e. A good consistency between ER change values is observed in different experiments: thermal martensitic transformation, stress induced martensitic transformation and stress induced reorientation of martensite variants. During stress induced martensitic transformation (superelastic behaviour and stress induced reorientation of martensite variants, a linear relationship is obtained between ER and strain as well as the absence of hys teresis. In conclusion, the present results show a direct evidence of martensite electrical resistivity anisotropy.

  5. A longitudinal study of relationships between previous academic achievement, emotional intelligence and personality traits with psychological health of medical students during stressful periods.

    Science.gov (United States)

    Yusoff, Muhamad Saiful Bahri; Esa, Ab Rahman; Mat Pa, Mohamad Najib; Mey, See Ching; Aziz, Rosniza Abdul; Abdul Rahim, Ahmad Fuad

    2013-01-01

    There is considerable evidence that emotional intelligence, previous academic achievement (i.e. cumulative grade point average (GPA)) and personality are associated with success in various occupational settings. This study evaluated the relationships of these variables with psychological health of first year medical students during stressful periods. A 1-year prospective study was done with students accepted into the School of Medical Sciences, Universiti Sains Malaysia. Information on emotional intelligence, GPA and personality traits were obtained prior to admission. The validated Universiti Sains Malaysia Emotional Quotient Inventory and Universiti Sains Malaysia Personality Inventory were used to measure emotional intelligence and personality traits, respectively. Stress, anxiety and depression were measured by the 21-item Depression Anxiety Stress Scale during the end-of-course (time 1) and final (time 2) examinations. At the less stressful period (time 1), stress level was associated with agreeableness and the final GPA, anxiety level was associated with emotional control and emotional conscientiousness and depression level was associated with the final GPA and extraversion. At the more stressful period (time 2), neuroticism associated with stress level, anxiety level was associated with neuroticism and emotional expression, and depression level was associated with neuroticism. This study found that neuroticism was the strongest associated factor of psychological health of medical students during their most stressful testing period. Various personality traits, emotional intelligence and previous academic performance were associated factors of psychological health during a less stressful period. These data suggest that early identification of medical students who are vulnerable to the stressful environment of medical schools might help them maintain psychological well-being during medical training.

  6. Genome-wide association analysis of seedling traits in diverse Sorghum germplasm under thermal stress

    OpenAIRE

    Chopra, Ratan; Burow, Gloria; Burke, John J.; Gladman, Nicholas; Xin, Zhanguo

    2017-01-01

    Background Climate variability due to fluctuation in temperature is a worldwide concern that imperils crop production. The need to understand how the germplasm variation in major crops can be utilized to aid in discovering and developing breeding lines that can withstand and adapt to temperature fluctuations is more necessary than ever. Here, we analyzed the genetic variation associated with responses to thermal stresses in a sorghum association panel (SAP) representing major races and workin...

  7. Differential stress resistance and metabolic traits underlie coexistence in a sympatrically evolved bacterial population

    NARCIS (Netherlands)

    Puentes Tellez, Pilar; van Elsas, Jan Dirk

    Following intermittent batch growth in Luria-Bertani (LB) broth for about 1000 generations, differentially evolved forms were found in a population of Escherichia coli cells. Studies on this population revealed the emergence of key polymorphisms, as evidenced by analysis of both whole genome

  8. Siderophores in clinical isolates of Klebsiella pneumoniae promote ciprofloxacin resistance by inhibiting the oxidative stress.

    Science.gov (United States)

    Zhang, Wenli; Zhang, Ying; Wang, Xinxin; Ding, Fengshu; Fu, Yingmei; Zhao, Jizi; Song, Wuqi; Opiyo, Ogutu James; Zhang, Fengmin; Chen, Xiaobei

    2017-09-23

    To explore the relevance of and understand the potential mechanisms behind the production of siderophores by clinical isolates of K. pneumoniae and ciprofloxacin (CIP) resistance, we divided the K. pneumoniae isolates into two groups based on bacterial siderophores production: high siderophore-yielding group (39 strains) and low siderophore-yielding group (38 strains). The rate of CIP resistance in K. pneumoniae (27/39 = 69.23%) from the high siderophore-yielding group was significantly higher than that (16/38 = 42.11%) in the low siderophore-yielding group (p  0.05). Siderophore-related antibiotic resistance was accompanied by efflux pump functions, but was not directly relevant to it. Furthermore, we found that the oxidative stress response was significantly lower in high siderophore-yielding strains compared to those isolates which had a low siderophores yield (12.17 vs. 30.91 of average fluorescence value; p oxidative stress response (p oxidative stress in both high and low siderophore-yielding strains (p oxidative stress in high siderophore-yielding strains was significantly lower than in low siderophore-yielding strains (p oxidative stress response, indicating that reduction of bacterial oxidative stress could provide a new avenue for control of bacterial drug resistance. Copyright © 2017. Published by Elsevier Inc.

  9. Growth on Alpha-Ketoglutarate Increases Oxidative Stress Resistance in the Yeast Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Maria Bayliak

    2017-01-01

    Full Text Available Alpha-ketoglutarate (AKG is an important intermediate in cell metabolism, linking anabolic and catabolic processes. The effect of exogenous AKG on stress resistance in S. cerevisiae cells was studied. The growth on AKG increased resistance of yeast cells to stresses, but the effects depended on AKG concentration and type of stressor. Wild-type yeast cells grown on AKG were more resistant to hydrogen peroxide, menadione, and transition metal ions (Fe2+ and Cu2+ but not to ethanol and heat stress as compared with control ones. Deficiency in SODs or catalases abolished stress-protective effects of AKG. AKG-supplemented growth led to higher values of total metabolic activity, level of low-molecular mass thiols, and activities of catalase and glutathione reductase in wild-type cells compared with the control. The results suggest that exogenous AKG may enhance cell metabolism leading to induction of mild oxidative stress. It turn, it results in activation of antioxidant system that increases resistance of S. cerevisiae cells to H2O2 and other stresses. The presence of genes encoding SODs or catalases is required for the expression of protective effects of AKG.

  10. Metabolomic analysis of the selection response of Drosophila melanogaster to environmental stress: are there links to gene expression and phenotypic traits?

    Science.gov (United States)

    Malmendal, Anders; Sørensen, Jesper Givskov; Overgaard, Johannes; Holmstrup, Martin; Nielsen, Niels Chr.; Loeschcke, Volker

    2013-05-01

    We investigated the global metabolite response to artificial selection for tolerance to stressful conditions such as cold, heat, starvation, and desiccation, and for longevity in Drosophila melanogaster. Our findings were compared to data from other levels of biological organization, including gene expression, physiological traits, and organismal stress tolerance phenotype. Overall, we found that selection for environmental stress tolerance changes the metabolomic 1H NMR fingerprint largely in a similar manner independent of the trait selected for, indicating that experimental evolution led to a general stress selection response at the metabolomic level. Integrative analyses across data sets showed little similarity when general correlations between selection effects at the level of the metabolome and gene expression were compared. This is likely due to the fact that the changes caused by these selection regimes were rather mild and/or that the dominating determinants for gene expression and metabolite levels were different. However, expression of a number of genes was correlated with the metabolite data. Many of the identified genes were general stress response genes that are down-regulated in response to selection for some of the stresses in this study. Overall, the results illustrate that selection markedly alters the metabolite profile and that the coupling between different levels of biological organization indeed is present though not very strong for stress selection at this level. The results highlight the extreme complexity of environmental stress adaptation and the difficulty of extrapolating and interpreting responses across levels of biological organization.

  11. Metabolomic analysis of the selection response of Drosophila melanogaster to environmental stress: are there links to gene expression and phenotypic traits?

    Science.gov (United States)

    Malmendal, Anders; Sørensen, Jesper Givskov; Overgaard, Johannes; Holmstrup, Martin; Nielsen, Niels Chr; Loeschcke, Volker

    2013-05-01

    We investigated the global metabolite response to artificial selection for tolerance to stressful conditions such as cold, heat, starvation, and desiccation, and for longevity in Drosophila melanogaster. Our findings were compared to data from other levels of biological organization, including gene expression, physiological traits, and organismal stress tolerance phenotype. Overall, we found that selection for environmental stress tolerance changes the metabolomic (1)H NMR fingerprint largely in a similar manner independent of the trait selected for, indicating that experimental evolution led to a general stress selection response at the metabolomic level. Integrative analyses across data sets showed little similarity when general correlations between selection effects at the level of the metabolome and gene expression were compared. This is likely due to the fact that the changes caused by these selection regimes were rather mild and/or that the dominating determinants for gene expression and metabolite levels were different. However, expression of a number of genes was correlated with the metabolite data. Many of the identified genes were general stress response genes that are down-regulated in response to selection for some of the stresses in this study. Overall, the results illustrate that selection markedly alters the metabolite profile and that the coupling between different levels of biological organization indeed is present though not very strong for stress selection at this level. The results highlight the extreme complexity of environmental stress adaptation and the difficulty of extrapolating and interpreting responses across levels of biological organization.

  12. Insulin resistance as a physiological defense against metabolic stress

    DEFF Research Database (Denmark)

    Nolan, Christopher J; Ruderman, Neil B; Kahn, Steven E

    2015-01-01

    challenging subgroup of patients with T2D who are overweight or obese with insulin resistance (IR) and the most refractory hyperglycemia due to an inability to change lifestyle to reverse positive energy balance. For this subgroup of patients with T2D, we question the dogma that IR is primarily harmful...

  13. Plant resistance to cold stress: Mechanisms and environmental ...

    Indian Academy of Sciences (India)

    Unknown

    The syndrome is even more complex because the various tissues of a plant are differently frost resistant, whereby meristematic cells are in general less frosthardy than mature tissues (Sakai and Larcher 1987). Another phenomenon that complicates the investigation of cold as a plant stressor is the seasonal change of frost.

  14. Variation in adult life history and stress resistance across five ...

    Indian Academy of Sciences (India)

    Unknown

    carbohydrate content, but its desiccation resistance per microgram carbohydrate was the lowest among the five spe- cies. In terms of overall performance, the laboratory population of D. melanogaster was clearly superior, under labo- ratory conditions, to the other four species if adult lifespan, lifetime fecundity, average daily ...

  15. P-body proteins regulate transcriptional rewiring to promote DNA replication stress resistance.

    Science.gov (United States)

    Loll-Krippleber, Raphael; Brown, Grant W

    2017-09-15

    mRNA-processing (P-) bodies are cytoplasmic granules that form in eukaryotic cells in response to numerous stresses to serve as sites of degradation and storage of mRNAs. Functional P-bodies are critical for the DNA replication stress response in yeast, yet the repertoire of P-body targets and the mechanisms by which P-bodies promote replication stress resistance are unknown. In this study we identify the complete complement of mRNA targets of P-bodies during replication stress induced by hydroxyurea treatment. The key P-body protein Lsm1 controls the abundance of HHT1, ACF4, ARL3, TMA16, RRS1 and YOX1 mRNAs to prevent their toxic accumulation during replication stress. Accumulation of YOX1 mRNA causes aberrant downregulation of a network of genes critical for DNA replication stress resistance and leads to toxic acetaldehyde accumulation. Our data reveal the scope and the targets of regulation by P-body proteins during the DNA replication stress response.P-bodies form in response to stress and act as sites of mRNA storage and degradation. Here the authors identify the mRNA targets of P-bodies during DNA replication stress, and show that P-body proteins act to prevent toxic accumulation of these target transcripts.

  16. Interactive Effects of Elevated [CO2] and Water Stress on Physiological Traits and Gene Expression during Vegetative Growth in Four Durum Wheat Genotypes.

    Science.gov (United States)

    Medina, Susan; Vicente, Rubén; Amador, Amaya; Araus, José Luis

    2016-01-01

    The interaction of elevated [CO2] and water stress will have an effect on the adaptation of durum wheat to future climate scenarios. For the Mediterranean basin these scenarios include the rising occurrence of water stress during the first part of the crop cycle. In this study, we evaluated the interactive effects of elevated [CO2] and moderate to severe water stress during the first part of the growth cycle on physiological traits and gene expression in four modern durum wheat genotypes. Physiological data showed that elevated [CO2] promoted plant growth but reduced N content. This was related to a down-regulation of Rubisco and N assimilation genes and up-regulation of genes that take part in C-N remobilization, which might suggest a higher N efficiency. Water restriction limited the stimulation of plant biomass under elevated [CO2], especially at severe water stress, while stomatal conductance and carbon isotope signature revealed a water saving strategy. Transcript profiles under water stress suggested an inhibition of primary C fixation and N assimilation. Nevertheless, the interactive effects of elevated [CO2] and water stress depended on the genotype and the severity of the water stress, especially for the expression of drought stress-responsive genes such as dehydrins, catalase, and superoxide dismutase. The network analysis of physiological traits and transcript levels showed coordinated shifts between both categories of parameters and between C and N metabolism at the transcript level, indicating potential genes and traits that could be used as markers for early vigor in durum wheat under future climate change scenarios. Overall the results showed that greater plant growth was linked to an increase in N content and expression of N metabolism-related genes and down-regulation of genes related to the antioxidant system. The combination of elevated [CO2] and severe water stress was highly dependent on the genotypic variability, suggesting specific genotypic

  17. Effects of Foliar Rates of Methanol Applications on some of Traits Related to Seed Yield of Sunflower (Helianthus annuus L. under Water Deficit Stress

    Directory of Open Access Journals (Sweden)

    E. Khalilvand Behrouzyar

    2014-07-01

    Full Text Available To investigate the effects of rates of methanol foliar applications under water deficit stress on someof traits related to seed yield of sunflower (Helianthus annuus L, a split plot experiment was conducted during growing seasons of 2011-2012. Treatments were four levels of water deficit stresses a1: severe stress (irrigation at 25% FC, a2: mild stress (irrigation at 50% FC, a3: fair stress (irrigation at 75% FC and a4: normal irrigation (irrigation at 100% FC and six levels of foliar methanol applications [b1:0, b2:7, b3:14, b4:21, b5:28 and b6:35 (v/v]. The analysis of variance showed significant effect of interaction between water deficit stress and methanol rates of foliar applications on seed yield per plant, dry weight per plant, number of seeds per head (p

  18. Biochemical basis of the high resistance to oxidative stress in ...

    Indian Academy of Sciences (India)

    Apoptosis; D. discoideum; oxidative stress; antioxidant enzymes; lipid peroxidation ... Dose-dependent induction of cell death by exogenous addition of hydrogen peroxide (H2O2), in situ generation of H2O2 by hydroxylamine, and nitric oxide (NO) generation by sodium nitroprusside treatment in D. discoideum were studied.

  19. Pneumococcal Gene Complex Involved in Resistance to Extracellular Oxidative Stress

    NARCIS (Netherlands)

    Farshchi Andisi, Vahid; Hinojosa, Cecilia A.; de Jong, Anne; Kuipers, Oscar P.; Orihuela, Carlos J.; Bijlsma, Jetta J. E.

    Streptococcus pneumoniae is a Gram-positive bacterium which is a member of the normal human nasopharyngeal flora but can also cause serious disease such as pneumonia, bacteremia, and meningitis. Throughout its life cycle, S. pneumoniae is exposed to significant oxidative stress derived from

  20. Heterosis analysis of Haemonchus contortus resistance and production traits in Rhoen sheep, Merino Land sheep and crossbred lambs.

    Science.gov (United States)

    Hielscher, A; Brandt, H; Erhardt, G; Gauly, M

    2006-11-05

    A crossbreeding program was conducted to evaluate the resistance status to Haemonchus contortus in reciprocal crossbred (F(1)) lambs and their Merino Land sheep (Ml) and Rhoen sheep (Rh) purebred counterparts. A total of 406 lambs were included in the study. Faecal egg counts (FEC) and haematocrit values (Hc) of all the lambs were collected 4 and 8 weeks after an artificial infection with H. contortus. FAMACHA scores were given at the same time. Worm counts of all lambs were obtained after slaughtering at 21 weeks of age. The Ml group consistently showed the highest body weights, daily weight gains and best carcass performances, whereas the Rh group showed the lowest results. Most of the body weight parameters in the F(1) group fell intermediately between the Ml and Rh groups, though the heterosis analysis of body weight and carcass parameters showed a tendency to favour the crossbreeding group Rh x Ml. The Rh group showed, on average, the highest FEC and the lowest Hc values compared to the Ml. However, the nematode counts were not significantly different between the pure breeds. In comparison, the worm counts of the Rh x Ml crosses were significantly different from those in the Ml x Rh crosses. A heterosis analysis showed that FEC, Hc and the worm count in the F(1) group favoured the crossbreeding group Rh x Ml. These results suggested that crossbreeding Rh to Ml sheep may be a suitable way of producing lambs with improved resistance to H. contortus infection without any negative effects on production traits.

  1. Behavioral, Performance, Carcass Traits and Hormonal Changes of Heat Stressed Broilers Feeding Black and Coriander Seeds

    Directory of Open Access Journals (Sweden)

    Ramadan D.M. EL-Shoukary

    2014-07-01

    Full Text Available The experiment was done to determine the effects of feeding heat stressed broilers (Ross308 diets contain Nigella Sativa seeds or coriander seeds on Ingestive, panting behaviors, feed consumption, weight gain, and feed conversion ratio, live body weight, slaughter weight, carcass weight and dressing percentage, corticosterone, triiodothyronine (T3 and tetraiodothyronine (T4. Three groups were used; the first one is the control group, which fed on basal diet only and the second fed diet contains 1% Nigella Sativa seeds (black seed while the third group fed diet contain 2% coriander seeds. The previous parameters were recorded daily or weekly during the experiment or after slaughtering to collecting blood parameters. The results explained that, there was a significant increase in feeding behavior, feed consumption, weight gain and dressing percentage while there was a significant decrease in panting behavior, water to feed ratio, T3 level and corticosterone level. Moreover, there was no significance difference in drinking behavior live body weight, slaughter weight, feed conversion rate and T4 level (P<0.05. It could be concluded that, black seeds and coriander seeds can be used to alleviate the negative effect of heat stress in broiler during summer seasons in Egypt.

  2. Effectively Coping With Task Stress: A Study of the Validity of the Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF).

    Science.gov (United States)

    O'Connor, Peter; Nguyen, Jessica; Anglim, Jeromy

    2017-01-01

    In this study, we investigated the validity of the Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF; Petrides, 2009) in the context of task-induced stress. We used a total sample of 225 volunteers to investigate (a) the incremental validity of the TEIQue-SF over other predictors of coping with task-induced stress, and (b) the construct validity of the TEIQue-SF by examining the mechanisms via which scores from the TEIQue-SF predict coping outcomes. Results demonstrated that the TEIQue-SF possessed incremental validity over the Big Five personality traits in the prediction of emotion-focused coping. Results also provided support for the construct validity of the TEIQue-SF by demonstrating that this measure predicted adaptive coping via emotion-focused channels. Specifically, results showed that, following a task stressor, the TEIQue-SF predicted low negative affect and high task performance via high levels of emotion-focused coping. Consistent with the purported theoretical nature of the trait emotional intelligence (EI) construct, trait EI as assessed by the TEIQue-SF primarily enhances affect and performance in stressful situations by regulating negative emotions.

  3. Consistent boldness behaviour in early emerging fry of domesticated Atlantic salmon (Salmo salar): Decoupling of behavioural and physiological traits of the proactive stress coping style.

    Science.gov (United States)

    Vaz-Serrano, J; Ruiz-Gomez, M L; Gjøen, H M; Skov, P V; Huntingford, F A; Overli, O; Höglund, E

    2011-06-01

    Individual variation in the way animals cope with stressors has been documented in a number of animal groups. In general, two distinct sets of behavioural and physiological responses to stress have been described: the proactive and the reactive coping styles. Some characteristics of stress coping style seem to be coupled to the time to emerge of fry from spawning redds in natural populations of salmonid fishes. In the present study, behavioural and physiological traits of stress coping styles were compared two and five months after emergence in farmed Atlantic salmon (Salmo salar), using individuals with an early or late time to emerge. Initially, compared to late emerging individuals, early emerging individuals showed a shorter time to resume feeding after transfer to rearing in isolation. Resumption of feeding after isolation was suggested to be related to boldness behaviour, rather than hunger, in the present study. This observation was repeated five months after emergence, demonstrating behavioural consistency over time in this trait. However, in other traits of proactive and reactive stress coping styles, such as social status, resting metabolism or post stress cortisol concentrations, early and late emerging individuals did not differ. Therefore, this study demonstrates that boldness in a novel environment is uncoupled from other traits of the proactive and reactive stress coping styles in farmed salmonids. It is possible that this decoupling is caused by the low competitive environment in which fish were reared. In natural populations of salmonids, however, the higher selection pressure at emergence could select for early emerging individuals with a proactive coping style. Copyright © 2011. Published by Elsevier Inc.

  4. Inheritance nature for the trait of resistance to neck rot in hybrid combinations of common onion under the conditions of Nosivka Variety Texting Station

    Directory of Open Access Journals (Sweden)

    Н. О. Горган

    2013-05-01

    Full Text Available The article highlights the results of studying hybrid combinations of common onion to the Botrytis allii Munn pathogen. It is found out that as for the combinations being studied the resistance to pathogen was inherited as dominant, intermediate or recessive trait. Better resistance to neck rot was inherent in the hybrid combinations which parents comprised resistant and immune varieties, insofar as the determination of inheritance coefficient has indicated F1 hybrids have this characteristic expression dependant by 50 to 78% on the parental plant (h2 =0,50–0,78. Studying the determination of the impact of both parental components on inheritance of the resistance to B. allii pathogen showed that the regression coefficient subject to hybrid combination fell within R = 0,12–0,39, while the resistance coefficient within 0,24–0,78, respectively. Efficiency of selection is proved by the trait of resistance to neck rot based on the populations of Grandina х Mavka, Olina х Grandina, Grandina х Skvyrska і Skvyrska х Grandina, as their respective inheritance coefficient reached the level of 0,42 to 0,78.

  5. [Improving industrial microbial stress resistance by metabolic engineering: a review].

    Science.gov (United States)

    Fu, Ruiyan; Li, Yin

    2010-09-01

    Metabolic engineering is a technologic platform for industrial strain improvement and aims not only at modifying microbial metabolic fluxes, but also improving the physiological performance of industrial microbes. Microbes will meet multiple stresses in industrial processes. Consequently, elicited gene responses might result in a decrease in overall cell fitness and the efficiency of biotransformation. Thus, it is crucial to develop robust and productive microbial strains that can be integrated into industrial-scale bioprocesses. In this review, we focus on the progress of these novel methods and strategies for engineering stress-tolerance phenotypes referring to rational metabolic engineering and inverse metabolic engineering in recent years. In addition, we also address problems existing in this area and future research needs of microbial physiological functionality engineering.

  6. Coral thermal tolerance: tuning gene expression to resist thermal stress.

    Directory of Open Access Journals (Sweden)

    Anthony J Bellantuono

    Full Text Available The acclimatization capacity of corals is a critical consideration in the persistence of coral reefs under stresses imposed by global climate change. The stress history of corals plays a role in subsequent response to heat stress, but the transcriptomic changes associated with these plastic changes have not been previously explored. In order to identify host transcriptomic changes associated with acquired thermal tolerance in the scleractinian coral Acropora millepora, corals preconditioned to a sub-lethal temperature of 3°C below bleaching threshold temperature were compared to both non-preconditioned corals and untreated controls using a cDNA microarray platform. After eight days of hyperthermal challenge, conditions under which non-preconditioned corals bleached and preconditioned corals (thermal-tolerant maintained Symbiodinium density, a clear differentiation in the transcriptional profiles was revealed among the condition examined. Among these changes, nine differentially expressed genes separated preconditioned corals from non-preconditioned corals, with 42 genes differentially expressed between control and preconditioned treatments, and 70 genes between non-preconditioned corals and controls. Differentially expressed genes included components of an apoptotic signaling cascade, which suggest the inhibition of apoptosis in preconditioned corals. Additionally, lectins and genes involved in response to oxidative stress were also detected. One dominant pattern was the apparent tuning of gene expression observed between preconditioned and non-preconditioned treatments; that is, differences in expression magnitude were more apparent than differences in the identity of genes differentially expressed. Our work revealed a transcriptomic signature underlying the tolerance associated with coral thermal history, and suggests that understanding the molecular mechanisms behind physiological acclimatization would be critical for the modeling of reefs

  7. Multiple roles of putrescine and spermidine in stress resistance and virulence of Salmonella enterica serovar Typhimurium

    DEFF Research Database (Denmark)

    Cartas Espinel, Irene; Guerra, Priscila Regina; Jelsbak, Lotte

    2016-01-01

    . Typhimurium virulence is the ability to survive and replicate inside macrophages and resisting the antimicrobial attacks in the form of oxidative and nitrosative stress elicited from these cells. In the present study, we have investigated the role of polyamines in intracellular survival and systemic...... infections of mice. Using a S. Typhimurium mutant defective for putrescine and spermidine biosynthesis, we show that polyamines are essential for coping with reactive nitrogen species, possibly linking polyamines to increased intracellular stress resistance. However, using a mouse model defective for nitric...

  8. Variation in adult stress resistance does not explain vulnerability to climate change in copper butterflies.

    Science.gov (United States)

    Klockmann, Michael; Wallmeyer, Leonard; Fischer, Klaus

    2017-03-15

    Ongoing climate change is a major threat to biodiversity. However, although many species clearly suffer from ongoing climate change, others benefit from it, for example, by showing range expansions. However, which specific features determine a species' vulnerability to climate change? Phenotypic plasticity, which has been described as the first line of defence against environmental change, may be of utmost importance here. Against this background, we here compare plasticity in stress tolerance in 3 copper butterfly species, which differ arguably in their vulnerability to climate change. Specifically, we investigated heat, cold and desiccation resistance after acclimatization to different temperatures in the adult stage. We demonstrate that acclimation at a higher temperature increased heat but decreased cold tolerance and desiccation resistance. Contrary to our predictions, species did not show pronounced variation in stress resistance, though plastic capacities in temperature stress resistance did vary across species. Overall, our results seemed to reflect population-rather than species-specific patterns. We conclude that the geographical origin of the populations used should be considered even in comparative studies. However, our results suggest that, in the 3 species studied here, vulnerability to climate change is not in the first place determined by stress resistance in the adult stage. As entomological studies focus all too often on adults only, we argue that more research effort should be dedicated to other developmental stages when trying to understand insect responses to environmental change. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  9. [Oxidative stress in adipose tissue as a primary link in pathogenesis of insulin resistance].

    Science.gov (United States)

    Kuzmenko, D I; Udintsev, S N; Klimentyeva, T K; Serebrov, V Yu

    2016-01-01

    Obesity is a leading risk factor of diabetes mellitus type 2, impairments of lipid metabolism and cardiovascular diseases. Dysfunctions of the accumulating weight of the visceral fat are primarily linked to pathogenesis of systemic insulin resistance. The review considers modern views about biochemical mechanisms underlying formation of oxidative stress in adipocytes at obesity, as one of key elements of impairments of their metabolism triggering formation of systemic insulin resistance.

  10. Signaling linkage between environmental stress resistance and leaf senescence in Arabidopsis.

    Science.gov (United States)

    Seo, Pil Joon; Park, Chung-Mo

    2011-10-01

    Plants possess versatile strategies that permit efficient use of limited nutrient resources during senescing process. This metabolic adjustment is critical for prevention of diverse cellular damage and thus for reproductive success and offspring production, particularly under environmental stress conditions. However, it is largely unknown how age-dependent resistance to cellular damages is established and how it is influenced by environmental stress signals during senescing process. We found that the VNI2 (VND-INTERACTING 2) transcription factor, which belongs to the NAC (NAM/ATAF1, 2/CUC2) transcription factor family, plays a role in the age-dependent induction of stress resistance. The VNI2 transcription factor is transcriptionally induced during senescing process and regulates COR/RD genes by binding directly to their promoters. The COR/RD proteins play a role in the protection from diverse cellular damages during senescing process. Notably, the transcriptional activation activity of VNI2 is further elevated under high salinity. These results indicate that plants increase environmental stress resistance by inducing the VNI2 gene to assure their reproductive success, supporting signaling crosstalk between stress resistance response and senescing process. 

  11. Cross tissue trait-pathway network reveals the importance of oxidative stress and inflammation pathways in obesity-induced diabetes in mouse.

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    Shouguo Gao

    Full Text Available Complex disorders often involve dysfunctions in multiple tissue organs. Elucidating the communication among them is important to understanding disease pathophysiology. In this study we integrate multiple tissue gene expression and quantitative trait measurements of an obesity-induced diabetes mouse model, with databases of molecular interaction networks, to construct a cross tissue trait-pathway network. The animals belong to two strains of mice (BTBR or B6, of two obesity status (obese or lean, and at two different ages (4 weeks and 10 weeks. Only 10 week obese BTBR animals are diabetic. The expression data was first utilized to determine the state of every pathway in each tissue, which is subsequently utilized to construct a pathway co-expression network and to define trait-relevant and trait-linking pathways. Among the six tissues profiled, the adipose contains the largest number of trait-linking pathways. Among the eight traits measured, the body weight and plasma insulin level possess the most number of relevant and linking pathways. Topological analysis of the trait-pathway network revealed that the glycolysis/gluconeogenesis pathway in liver and the insulin signaling pathway in muscle are of top importance to the information flow in the network, with the highest degrees and betweenness centralities. Interestingly, pathways related to metabolism and oxidative stress actively interact with many other pathways in all animals, whereas, among the 10 week animals, the inflammation pathways were preferentially interactive in the diabetic ones only. In summary, our method offers a systems approach to delineate disease trait relevant intra- and cross tissue pathway interactions, and provides insights to the molecular basis of the obesity-induced diabetes.

  12. Genetic variants and traits related to insulin-like growth factor-I and insulin resistance and their interaction with lifestyles on postmenopausal colorectal cancer risk.

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    Su Yon Jung

    Full Text Available Genetic variants and traits in metabolic signaling pathways may interact with lifestyle factors such as obesity, physical activity, and exogenous estrogen (E, influencing postmenopausal colorectal cancer (CRC risk, but these interrelated pathways are not fully understood. In this case-cohort study, we examined 33 single-nucleotide polymorphisms (SNPs in genes related to insulin-like growth factor-I (IGF-I/ insulin resistance (IR traits and signaling pathways, using data from 704 postmenopausal women in Women's Health Initiative Observation ancillary studies. Stratifying by the lifestyle modifiers, we assessed the effects of IGF-I/IR traits (fasting total and free IGF-I, IGF binding protein-3, insulin, glucose, and homeostatic model assessment-insulin resistance on CRC risk as a mediator or influencing factor. Six SNPs in the INS, IGF-I, and IGFBP3 genes were associated with CRC risk, and those associations differed between non-obese/active and obese/inactive women and between E nonusers and users. Roughly 30% of the cancer risk due to the SNP was mediated by IGF-I/IR traits. Likewise, carriers of 11 SNPs in the IRS1 and AKT1/2 genes (signaling pathway-related genetic variants had different associations with CRC risk between strata, and the proportion of the SNP-cancer association explained by traits varied from 30% to 50%. Our findings suggest that IGF-I/IR genetic variants interact with obesity, physical activity, and exogenous E, altering postmenopausal CRC risk, through IGF-I/IR traits, but also through different pathways. Unraveling gene-phenotype-lifestyle interactions will provide data on potential genetic targets in clinical trials for cancer prevention and intervention strategies to reduce CRC risk.

  13. FLCN and AMPK Confer Resistance to Hyperosmotic Stress via Remodeling of Glycogen Stores.

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    Elite Possik

    2015-10-01

    Full Text Available Mechanisms of adaptation to environmental changes in osmolarity are fundamental for cellular and organismal survival. Here we identify a novel osmotic stress resistance pathway in Caenorhabditis elegans (C. elegans, which is dependent on the metabolic master regulator 5'-AMP-activated protein kinase (AMPK and its negative regulator Folliculin (FLCN. FLCN-1 is the nematode ortholog of the tumor suppressor FLCN, responsible for the Birt-Hogg-Dubé (BHD tumor syndrome. We show that flcn-1 mutants exhibit increased resistance to hyperosmotic stress via constitutive AMPK-dependent accumulation of glycogen reserves. Upon hyperosmotic stress exposure, glycogen stores are rapidly degraded, leading to a significant accumulation of the organic osmolyte glycerol through transcriptional upregulation of glycerol-3-phosphate dehydrogenase enzymes (gpdh-1 and gpdh-2. Importantly, the hyperosmotic stress resistance in flcn-1 mutant and wild-type animals is strongly suppressed by loss of AMPK, glycogen synthase, glycogen phosphorylase, or simultaneous loss of gpdh-1 and gpdh-2 enzymes. Our studies show for the first time that animals normally exhibit AMPK-dependent glycogen stores, which can be utilized for rapid adaptation to either energy stress or hyperosmotic stress. Importantly, we show that glycogen accumulates in kidneys from mice lacking FLCN and in renal tumors from a BHD patient. Our findings suggest a dual role for glycogen, acting as a reservoir for energy supply and osmolyte production, and both processes might be supporting tumorigenesis.

  14. Effect of Zeolite, Selenium and Silicon on Yield, Yield Components and Some Physiological Traits of Canola under Salt Stress Conditions

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    A Bybordi

    2016-07-01

    Full Text Available Introduction Canola can be cultivated in large areas of the country due to its specific characteristics such as suitable composition of the fatty acids, its germination ability under low temperature, as well as its good compatibility with different climates. Canola is a high demanding crop in terms of fertilizers so that it uptakes considerable amount of nutrients from the soil during the growing season. Canola cultivation in poor soils or application of imbalanced fertilizers, especially nitrogen, can reduce qualitaty and quantity of final yield. On the other hand, salinity is known as one of the major limiting factors in canola production. Therefore, the aim of this study is the application of zeolite, selenium and silicon treatments to amend soil and increasing salinity tolerance in canola. Materials and Methods In order to study the effect of soil applied zeolite and foliar application of selenium and silicon on yield, yield components and some physiological traits of canola grown under salinity stress, a factorial experiment in randomized complete block design was conducted in Agriculture and Natural Resource Research Center in East Azerbaijan during 2011-2013 cropping seasons. Zeolite was applied at three levels (0, 5 and 10 ton ha-1 and foliar selenium and silicon were applied at three levels as well (each one zero, 2 and 4 g l-1. For this purpose, seedbed was prepared using plow and disk and then plot were designed. Canola seeds, cultivar Okapi, were sown in sandy loam soil with 4 dS.m-1 salinity at the depth of 2-3 cm. Irrigation was performed using local well based on 60% field capacity using the closed irrigation system. Potassium selentae and potassium silicate were used for selenium and silicon treatments. Treatments at rosette and stem elongation stages were sprayed on plants using a calibrated pressurized backpack sprayer. At flowering stage, photosynthesis rate was recorded. Then leaf samples were randomly collected to assay

  15. Targeting the cell stress response of Plasmodium falciparum to overcome artemisinin resistance.

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    Con Dogovski

    2015-04-01

    Full Text Available Successful control of falciparum malaria depends greatly on treatment with artemisinin combination therapies. Thus, reports that resistance to artemisinins (ARTs has emerged, and that the prevalence of this resistance is increasing, are alarming. ART resistance has recently been linked to mutations in the K13 propeller protein. We undertook a detailed kinetic analysis of the drug responses of K13 wild-type and mutant isolates of Plasmodium falciparum sourced from a region in Cambodia (Pailin. We demonstrate that ART treatment induces growth retardation and an accumulation of ubiquitinated proteins, indicative of a cellular stress response that engages the ubiquitin/proteasome system. We show that resistant parasites exhibit lower levels of ubiquitinated proteins and delayed onset of cell death, indicating an enhanced cell stress response. We found that the stress response can be targeted by inhibiting the proteasome. Accordingly, clinically used proteasome inhibitors strongly synergize ART activity against both sensitive and resistant parasites, including isogenic lines expressing mutant or wild-type K13. Synergy is also observed against Plasmodium berghei in vivo. We developed a detailed model of parasite responses that enables us to infer, for the first time, in vivo parasite clearance profiles from in vitro assessments of ART sensitivity. We provide evidence that the clinical marker of resistance (delayed parasite clearance is an indirect measure of drug efficacy because of the persistence of unviable parasites with unchanged morphology in the circulation, and we suggest alternative approaches for the direct measurement of viability. Our model predicts that extending current three-day ART treatment courses to four days, or splitting the doses, will efficiently clear resistant parasite infections. This work provides a rationale for improving the detection of ART resistance in the field and for treatment strategies that can be employed in areas

  16. Effect of Salinity Stress on Physiological and Biochemical Traits in Citrus Genotypes

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    B. Golein

    2016-02-01

    .Treatment included 10 citrus natural genotypes along with two varieties of Cleopatra mandarin (tolerant plant and Swinglecitrumelo (sensitive plant with six-month old and four salinity levels of sodium chloride: 0(control, 2, 4 and 6 dsm-1, for 16 weeks in the greenhouse condition. Effect of salinity on fresh and dry weight of shoot and root, relative water content (using upper leaves, stomatal density (with counting of stomata using microscope, concentration ofCl (with titration method of silver nitrate and Na (by flame photometry in roots and leaves, content of total chlorophyll (using acetone 80%, proline (spectrophotometry at wavelength of 520 nm, lipid peroxidation (spectrophotometry at wavelength of 532 nm and activity of peroxidase enzyme (spectrophotometry at wavelength of 470 nmwere investigated. Data analysis was done by SAS 9.1 software. Results and Discussion: The results indicated that, the interaction of genotypes and salinity levels hadnot significant difference in relative water content, stomatal density and Na+concentration - in roots but, other traits except total chlorophyll content which was significant at 5% level, were significant at 1% level. Shoot fresh and dry weight of genotypes No. 4 and 6 were significantly (P

  17. Brain responses to chronic social defeat stress: effects on regional oxidative metabolism as a function of a hedonic trait, and gene expression in susceptible and resilient rats.

    Science.gov (United States)

    Kanarik, Margus; Alttoa, Aet; Matrov, Denis; Kõiv, Kadri; Sharp, Trevor; Panksepp, Jaak; Harro, Jaanus

    2011-01-01

    Chronic social defeat stress, a depression model in rats, reduced struggling in the forced swimming test dependent on a hedonic trait-stressed rats with high sucrose intake struggled less. Social defeat reduced brain regional energy metabolism, and this effect was also more pronounced in rats with high sucrose intake. A number of changes in gene expression were identified after social defeat stress, most notably the down-regulation of Gsk3b and Map1b. The majority of differences were between stress-susceptible and resilient rats. Conclusively, correlates of inter-individual differences in stress resilience can be identified both at gene expression and oxidative metabolism levels. Copyright © 2010 Elsevier B.V. and ECNP. All rights reserved.

  18. Investigating the interactive role of stressful life events, reinforcement sensitivity and personality traits in prediction of the severity of Multiple Sclerosis (MS symptoms

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    2017-06-01

    Full Text Available Background & Objective: Multiple sclerosis is a chronic neurological condition recognized by demyelination in the central nervous system. The present study was conducted to investigate the interactive role of stressful life events, reinforcement sensitivity, and personality traits in prediction of the severity of symptoms of Multiple sclerosis (MS symptoms. Materials & Methods: This is a correlational study whose statistical population consisted of all the patients suffering from Multiple Sclerosis in Shiraz in the first half of 1394, among whom 162 patients were included in this research by means of purposive sampling method. Five-Factor Personality Inventory, Jackson Personality Inventory, Stressful Life Events Scale, and Expanded Disability Status Scale (EDSS were utilised as research tools. In order to analyze the data, descriptive and inferential methods were used. The data were analysed using Pearson correlation and hierarchical regression. Results: The findings revealed that stressful life events (β = 0.41, p <0.001, Behavioral Inhibition System (β = 0.26, p<0.05, and neuroticism index (β = 0.92, p <0.05 were able to predict variance of scores of the severity of symptoms of Multiple Sclerosis significantly. Conclusion: Stressful life events, Behavioral Inhibition System, and neuroticism showed a significant relationship with the severity of symptoms of Multiple Sclerosis; thus, it seems that interaction of personality traits and environmental conditions are among influential factors of the severity of symptoms of Multiple Sclerosis. This fact implies that individuals' personal traits play an eminent role in the progression of the disease.

  19. Parental attitudes and personality traits, self-efficacy, stress, and coping strategies among mothers of children with cerebral palsy

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    Anna Maria Jankowska

    2015-06-01

    Full Text Available Background Development of children with cerebral palsy (CP depends on the quality of parental care. The aim of the research was to compare parenting attitudes in mothers of children with CP to mothers of typically developing children, and to study the relationship between parenting attitudes and personality traits, stress, coping strategies and self-efficacy in mothers of children with CP. Participants and procedure Twenty-seven mothers of children with cerebral palsy (MCCP (mean age 35.50 years, SD = 4.83 and twenty-eight mothers (mean age 35.60 years, SD = 4.27 of typically developing children (MTDC participated in this study. Each parent had a child between the ages of two and seven years. A battery of tests was administered to both groups, which included the Parenting Attitudes Scale (SPR, the NEO Five-Factor Inventory (NEO-FFI, the Generalized Self-Efficacy Scale (GSES, and the COPE Inventory. Also, maternal stress and the amount of social support received were assessed. Results Although acceptance was the most common parental attitude among all participants, mothers of children with CP presented with a stronger tendency towards overprotective and demanding attitudes. MCCP obtained higher scores in neuroticism and lower in openness compared to MTDC. Furthermore, MCCP declared a higher level of distress than MTDC. There were no statistically significant differences between the two groups of mothers regarding self-efficacy, the level of social support or the most often used coping strategies. Neuroticism was found to be the best predictor of overprotective and demanding parental attitudes. Conclusions The study emphasises the importance of parenting programmes for mothers with children with CP to promote the development of autonomy among children with developmental difficulties.

  20. Effects of Cycocel on Morphological Traits, Nitrogen and Potassium Content of Basil Plants under Water Stress Conditions

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    A Rezaei Estakhroeih

    2016-10-01

    -plots. Cultivation was carried out in March and harvested in late June. In this study the plant height, fresh and dry weight of root and shoot, root to shoot dry weight ratio, percentage of nitrogen and potassium, leaf relative water content and leaf area index were measured. For its statistical calculation, SAS (v. 9.1 software and for the comparison of the averages the Duncan’s test was used. The level of possibility used in the analysis was five percent. Results and Discussion The result of the analysis of variance of measured traits has shown in Table 1. Data analysis of variance (Table 1 shows different levels of irrigation, Cycocel and irrigation with Cycocel interaction were significant at the level of one percent on plant height. Effects of different irrigation treatments and Cycocel concentration on fresh and dry weight of shoot were significant at one and five percent, respectively. However, the effect of irrigation and Cycocel interaction on shoot dry weight was not significant. Root fresh and dry weight were influenced by irrigation levels (Table 1. The effect of irrigation and Cycocel interaction on root dry weight, percent of nitrogen and dry weight of root to shoot ratio was significantat one percent. The effect of irrigation on root to shoot dry weight ratio was not significant. Moreover, the effects of Cycocel treatments on root to shoot dry weight ratio were significant at the five percent level. The effect of irrigation, Cycocel on percent of nitrogen and potassium was significant and potassium decreased with the increasing of water stress. The highest percentage of potassium (2.26% belonged to the full irrigation and the concentration of 2000 milligrams per litre Cycocel and the lowest belonged to the interaction of severe stress and zero, 500 and 1000 milligrams per litre Cycocel. Irrigation and Cycocel had a significant influence on leaf relative water content at the level of one percent. Conclusions According to the results which obtained through this study

  1. Heritable, de novo resistance to leaf rust and other novel traits in selfed descendants of wheat responding to inoculation with wheat streak mosaic virus.

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    Dallas L Seifers

    Full Text Available Stable resistance to infection with Wheat streak mosaic virus (WSMV can be evolved de novo in selfing bread wheat lines subjected to cycles of WSMV inoculation and selection of best-performing plants or tillers. To learn whether this phenomenon might be applied to evolve resistance de novo to pathogens unrelated to WSMV, we examined the responses to leaf rust of succeeding generations of the rust- and WSMV-susceptible cultivar 'Lakin' following WSMV inoculation and derived rust-resistant sublines. After three cycles of the iterative protocol five plants, in contrast to all others, expressed resistance to leaf and stripe rust. A subset of descendant sublines of one of these, 'R1', heritably and uniformly expressed the new trait of resistance to leaf rust. Such sublines, into which no genes from a known source of resistance had been introgressed, conferred resistance to progeny of crosses with susceptible parents. The F1 populations produced from crosses between, respectively, susceptible and resistant 'Lakin' sublines 4-3-3 and 4-12-3 were not all uniform in their response to seedling inoculation with race TDBG. In seedling tests against TDBG and MKPS races the F2s from F1 populations that were uniformly resistant had 3∶1 ratios of resistant to susceptible individuals but the F2s from susceptible F1 progenitors were uniformly susceptible. True-breeding lines derived from resistant individuals in F2 populations were resistant to natural stripe and leaf rust inoculum in the field, while the 'Lakin' progenitor was susceptible. The next generation of six of the 'Lakin'-derived lines exhibited moderate to strong de novo resistance to stem rust races TPMK, QFCS and RKQQ in seedling tests while the 'Lakin' progenitor was susceptible. These apparently epigenetic effects in response to virus infection may help researchers fashion a new tool that expands the range of genetic resources already available in adapted germplasm.

  2. Quantitative Trait Loci Associated with Pollen Fertility under High Temperature Stress at Flowering Stage in Rice (Oryza sativa

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    Ying-hui XIAO

    2011-09-01

    Full Text Available High temperature stress (HTS, an increasingly important problem in rice production, significantly reduces rice yield by reducing pollen fertility and seed setting rate. Breeding rice varieties with tolerance to HTS at the flowering stage is therefore essential for maintaining rice production as the climate continues to become warm. In this study, two quantitative trait loci (QTLs underlying tolerance to HTS were identified using recombinant inbred lines derived from a cross between an HTS-tolerant rice cultivar 996 and a sensitive cultivar 4628. Pollen fertility was used as a heat-tolerance indicator for the lines subjected to HTS at the flowering stage in field experiments. Two QTLs that affected pollen fertility, qPF4 and qPF6, were detected between RM5687 and RM471 on chromosome 4, and between RM190 and RM225 on chromosome 6, by using the composite interval mapping (CIM analysis. The two QTLs explained 15.1% and 9.31% of the total phenotypic variation in pollen fertility, and increased the pollen fertility of the plants subjected to HTS by 7.15% and 5.25%, respectively. The positive additive effects of the two QTLs were derived from the 996 alleles. The two major QTLs identified would be useful for further fine mapping and cloning of these genes and for molecular marker-assistant breeding of heat-tolerant rice varieties.

  3. Effect of Ca, K, and Mn Foliar Spray on Vegetative Traits of Safflower (Carthamus tinctorius L. under Salt Stress

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    M. Attarzadeh

    2014-12-01

    Full Text Available In order to study the effect of Ca, K, and Mn foliar spray on vegetative traits of safflower (Padideh cultivar under salt stress, a factorial experiment was conducted based on randomized complete blocks design with three replications in Vali-asr university greenhouse. Factors included salinity with four levels representing 0, 500, 1000, and 1500 mg NaCl kg -1, and foliar spray with four level representing 10 mM spray of distilled water, CaNo3, K2HPO4 and MnSo4, 1 mM spray, respectively, sprayed two weeks after emergence, one application per 2 weeks. Results showed that increasing salinity level, reduced plant dry weight, leaf area, height, while salinity and foliar spray treatments has no effect on number of leaves. Highest leaf area was obtained after K2HPO4 and CaNo3 foliar spray, and lowest leaf area was obtained from MnSo4, K2HPO4 and CaNo3 foliar spray prevented somewhat early plant growth rate reduction treated with 500 and 1000 mg NaCl. Applying 1500 mg NaCl reduced SPAD value, and leaf chlorophyll fluorescence. MnSo4, K2HPO4 and CaNo3 foliar spray nutrients, also reduced SPAD value.

  4. [Psychological features of body integrity identity disorder (BIID): personality traits, interpersonal aspects, coping mechanisms regarding stress and conflicts, body perception].

    Science.gov (United States)

    Oddo, S; Möller, J; Skoruppa, S; Stirn, A

    2014-05-01

    In BIID a disorder of body identity, concerned subjects desire an amputation of a healthy limb. So far, no psychiatric comorbidity was found in the few studies on BIID-subjects. This study explored clinical symptoms, personality characteristics, interpersonal aspects and coping strategies in 15 BIID persons. Psychometric testing on the topics (1) clinical symptoms, (2) personality and interpersonal aspects, (3) coping strategies, (4) attitudes towards the body were used and statistically evaluated with the T-test for one sample. Some psychopathologies such as depression, anxiety and obsessive-compulsive disorders (OCD) could be excluded although an increased tendency of depressiveness was found. BIID subjects showed specific personality and interpersonal characteristics: high agreeableness, autonomy, autarky and restrained behaviour towards others. Stress and conflicts are managed by self-control and self-affirmation. Their subjective physical attractiveness was low. BIID persons do not exhibit psychopathological characteristics (such as anxiety, depression or OCD), but do show specifics in personality, relationships and coping mechanisms. In the future, further personality traits and personality disorders should be investigated to shed more light on the categorisation and treatment of BIID. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Influence of trait anxiety on the effects of acute stress on learning and retention of the passive avoidance task in male and female mice.

    Science.gov (United States)

    Navarro-Francés, Concepción I; Arenas, M Carmen

    2014-06-01

    The influence of anxiety on the effects of acute stress for the acquisition and retention of passive avoidance conditioned task was evaluated in male and female mice. Animals were categorized as high-, medium-, and low-anxiety according to their performance in the elevated plus-maze test. Subsequently, half of the mice in each group were exposed to an acute stressor and assayed in an aversive conditioning test two days later. Exposure to restraint stress before inhibitory avoidance conditioning had a differential impact on the conditioned response of males and females according to their trait anxiety. The acute stressor significantly altered the conditioned response of mice with a high-anxiety level. The long-term effect of the stressor varied for each sex; high-anxiety stressed males showed an enhanced conditioned response with respect to their controls, whereas high-anxiety stressed females presented an impaired performance. These results lead us to believe that the characterization of individuality is an important factor in understanding the interaction between stress and memory for each sex; the trait anxiety of our animals modulated the effects of stress on the conditioned response so that males and females performed in contrasting manners to the same environmental stimuli and experimental conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Heightened reward learning under stress in generalized anxiety disorder: a predictor of depression resistance?

    Science.gov (United States)

    Morris, Bethany H; Rottenberg, Jonathan

    2015-02-01

    Stress-induced anhedonia is associated with depression vulnerability (Bogdan & Pizzagalli, 2006). We investigated stress-induced deficits in reward learning in a depression-vulnerable group with analogue generalized anxiety disorder (GAD, n = 34), and never-depressed healthy controls (n = 41). Utilizing a computerized signal detection task, reward learning was assessed under stressor and neutral conditions. Controls displayed intact reward learning in the neutral condition, and the expected stress-induced blunting. The GAD group as a whole also showed intact reward learning in the neutral condition. When GAD subjects were analyzed as a function of prior depression history, never-depressed GAD subjects showed heightened reward learning in the stressor condition. Better reward learning under stress among GAD subjects predicted lower depression symptoms 1 month later. Robust reward learning under stress may indicate depression resistance among anxious individuals. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  7. Differential response of DDT susceptible and resistant Drosophila melanogaster strains to DDT and oxidative stress

    Science.gov (United States)

    Metabolic DDT resistance in Drosophila melanogaster is associated with increased cytochrome P450 expression. Increased P450 activity is also associated with increased oxidative stress. In contrast, increased glutathione S transferase (GST) expression has been associated with a greater ability of o...

  8. Mitofusin 2 in POMC neurons connects ER stress with leptin resistance and energy imbalance

    DEFF Research Database (Denmark)

    Schneeberger, Marc; Dietrich, Marcelo O; Sebastián, David

    2013-01-01

    Mitofusin 2 (MFN2) plays critical roles in both mitochondrial fusion and the establishment of mitochondria-endoplasmic reticulum (ER) interactions. Hypothalamic ER stress has emerged as a causative factor for the development of leptin resistance, but the underlying mechanisms are largely unknown....

  9. High viscosity and anisotropy characterize the cytoplasm of fungal dormant stress-resistant spores

    NARCIS (Netherlands)

    Dijksterhuis, J; Nijsse, J; Hoekstra, F A; Golovina, E A

    Ascospores of the fungus Talaromyces macrosporus are dormant and extremely stress resistant, whereas fungal conidia--the main airborne vehicles of distribution--are not. Here, physical parameters of the cytoplasm of these types of spores were compared. Cytoplasmic viscosity and level of anisotropy

  10. Resistance to early-life stress in mice: effects of genetic background and stress duration

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    Helene M. Savignac

    2011-04-01

    Full Text Available Early-life stress can induce marked behavioural and physiological impairments in adulthood including cognitive deficits, depression, anxiety and gastrointestinal dysfunction. Although robust rat models of early-life stress exist there are few established effective paradigms in the mouse. Genetic background and protocol parameters used are two critical variables in such model development.Thus we investigated the impact of two different early-life stress protocols in two commonly used inbred mouse strains. C57BL/6 and innately anxious BALB/c male mice were maternally deprived 3 hrs daily, either from postnatal day 1 to 14 (Protocol 1 or 6 to 10 (Protocol 2. Animals were assessed in adulthood for cognitive performance (spontaneous alternation behaviour test, anxiety (open field, light/dark box and elevated plus maze tests and depression-related behaviours (forced swim test in addition to stress-sensitive physiological changes. Overall, the results showed that early-life stressed mice from both strains displayed good cognitive ability and no elevations in anxiety. However, paradoxical changes occurred in C57BL/6 mice as the longer protocol (protocol 1 decreased anxiety in the light-dark box and increased exploration in the elevated plus maze. In BALB/c mice there were also limited effects of maternal separation with both separation protocols inducing reductions in stress-induced defecation and protocol 1 reducing the colon length. These data suggest that, independent of stress duration, mice from both strains were on the whole resilient to the maladaptive effects of early-life stress. Thus maternal-separation models of brain-gut axis dysfunction should rely on either different stressor protocols or other strains of mice.

  11. Impact of acute psychological stress on cardiovascular risk factors in face of insulin resistance.

    Science.gov (United States)

    Jones, Kristian T; Shelton, Richard C; Wan, Jun; Li, Li

    2016-11-01

    Individuals with insulin resistance (IR) are at greater risk for cardiovascular disease (CVD). Psychological stress may contribute to develop CVD in IR, although mechanisms are poorly understood. Our aim was to test the hypothesis that individuals with IR have enhanced emotional and physiological responses to acute psychological stress, leading to increased CVD risk. Sixty participants were enrolled into the study, and classified into IR group (n = 31) and insulin sensitive group (n = 29) according to the Quantitative insulin sensitivity check index, which was calculated based on an oral glucose tolerance test. The Trier social stress test, a standardized experimental stress paradigm, was performed on each participant, and emotional and physiological responses were examined. Blood was collected from each subject for insulin, cytokines, and cortisol measurements. Compared with the insulin-sensitive group, individuals with IR had significantly lower ratings of energy and calm, but higher fatigue levels in response to acute stressors. Individuals with IR also showed blunted heart rate reactivity following stress. In addition, the IR status was worsened by acute psychological stress as demonstrated by further increased insulin secretion. Furthermore, individuals with IR showed significantly increased levels of leptin and interleukin-6, but decreased levels of adiponectin, at baseline, stress test, and post-stress period. Our findings in individuals with IR under acute stress would allow a better understanding of the risks for developing CVD and to tailor the interventions for better outcomes.

  12. The RNA-editing deaminase ADAR is involved in stress resistance of Artemia diapause embryos.

    Science.gov (United States)

    Dai, Li; Liu, Xue-Chen; Ye, Sen; Li, Hua-Wei; Chen, Dian-Fu; Yu, Xiao-Jian; Huang, Xue-Ting; Zhang, Li; Yang, Fan; Yang, Jin-Shu; Yang, Wei-Jun

    2016-11-01

    The most widespread type of RNA editing, conversion of adenosine to inosine (A→I), is catalyzed by two members of the adenosine deaminase acting on RNA (ADAR) family, ADAR1 and ADAR2. These enzymes edit transcripts for neurotransmitter receptors and ion channels during adaption to changes in the physical environment. In the primitive crustacean Artemia, when maternal adults are exposed to unfavorable conditions, they release diapause embryos to withstand harsh environments. The aim of the current study was therefore to elucidate the role of ADAR of Artemia diapause embryos in resistance to stress. Here, we identified Artemia ADAR (Ar-ADAR), which harbors a putative nuclear localization sequence (NLS) and two double-stranded RNA-binding motifs (dsRBMs) in the amino-terminal region and an adenosine deaminase (AD) domain in the carboxyl-terminal region. Western blot and immunofluorescence analysis revealed that Ar-ADAR is expressed abundantly in post-diapause embryos. Artemia (n = 200, three replicates) were tested under basal and stress conditions. We found that Ar-ADAR was significantly induced in response to the stresses of salinity and heat-shock. Furthermore, in vivo knockdown of Ar-ADAR (n = 100, three replicates) by RNA interference induced formation of pseudo-diapause embryos, which lack resistance to the stresses and exhibit high levels of apoptosis. These results indicate that Ar-ADAR contributes to resistance to stress in Artemia diapause embryos.

  13. Alcohol dehydrogenase 1 (ADH1) confers both abiotic and biotic stress resistance in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Liu, Wen; Yao, Yue; Wei, Yunxie; Chan, Zhulong

    2017-09-01

    Although the transcriptional regulation and upstream transcription factors of AtADH1 in response to abiotic stress are widely revealed, the in vivo roles of AtADH1 remain unknown. In this study, we found that the expression of AtADH1 was largely induced after salt, drought, cold and pathogen infection. Further studies found that AtADH1 overexpressing plants were more sensitive to abscisic acid (ABA) in comparison to wide type (WT), while AtADH1 knockout mutants showed no significant difference compared with WT in ABA sensitivity. Consistently, AtADH1 overexpressing plants showed improved stress resistance to salt, drought, cold and pathogen infection than WT, but the AtADH1 knockout mutants had no significant difference in abiotic and biotic stress resistance. Moreover, overexpression of AtADH1 expression increased the transcript levels of multiple stress-related genes, accumulation of soluble sugars and callose depositions. All these results indicate that AtADH1 confers enhanced resistance to both abiotic and biotic stresses. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Oxidative stress and diabetes: what can we learn about insulin resistance from antioxidant mutant mouse models?

    Science.gov (United States)

    Styskal, JennaLynn; Van Remmen, Holly; Richardson, Arlan; Salmon, Adam B.

    2011-01-01

    The development of metabolic dysfunctions like diabetes and insulin resistance in mammals is regulated by a myriad of factors. Oxidative stress seems to play a central role in this process as recent evidence shows a general increase in oxidative damage and a decrease in oxidative defense associated with several metabolic diseases. These changes in oxidative stress can be directly correlated with increased fat accumulation, obesity and consumption of high calorie/high fat diets. Modulation of oxidant protection through either genetic mutation or treatment with antioxidants can significantly alter oxidative stress resistance and accumulation of oxidative damage in laboratory rodents. Antioxidant mutant mice have previously been utilized to examine the role of oxidative stress in other disease models, but have been relatively unexplored as models to study the regulation of glucose metabolism. In this review, we will discuss the evidence for oxidative stress as a primary mechanism linking obesity and metabolic disorders and whether alteration of antioxidant status in laboratory rodents can significantly alter the development of insulin resistance or diabetes. PMID:22056908

  15. Regulation of oxidative stress resistance in Campylobacter jejuni, a microaerophilic foodborne pathogen

    Science.gov (United States)

    Kim, Jong-Chul; Oh, Euna; Kim, Jinyong; Jeon, Byeonghwa

    2015-01-01

    Campylobacter jejuni is one of the leading bacterial causes of human gastroenteritis. Due to the increasing rates of human campylobacteriosis, C. jejuni is considered as a serious public health concern worldwide. C. jejuni is a microaerophilic, fastidious bacterium. C. jejuni must overcome a wide range of stress conditions during foodborne transmission to humans, such as food preservation and processing conditions, and even in infection of the gastrointestinal tracts of humans. Particularly, this microaerophilic foodborne pathogen must survive in the atmospheric conditions prior to the initiation of infection. C. jejuni possesses unique regulatory mechanisms for oxidative stress resistance. Lacking OxyR and SoxRS that are highly conserved in other Gram-negative foodborne pathogens, C. jejuni modulates the expression of genes involved in oxidative stress resistance mainly via the peroxide resistance regulator and Campylobacter oxidative stress regulator. Based on recent findings of ours and others, in this review, we described how C. jejuni regulates the expression of oxidative stress defense. PMID:26284041

  16. [Comparison of parameters of stress and trait anxiety in teenagers who are brought up in full, incomplete families, and families with the replaced parents].

    Science.gov (United States)

    Shkol'nik, T K; Lushchekina, E A; Kulikov, M A; Aĭrapetiants, M G

    2009-01-01

    166 teenagers in the age of 15-17 years were investigated on the influence of socially adverse conditions of education upon the level of trait anxiety and presence of stress. Teenagers who were brought up in socially unsuccessful conditions (in family with registered cases of alcoholism, violence, suicide, etc.; in family of relatives; with trustees) and also teenagers who were brought up in incomplete families show higher level of trait anxiety (even if initially they have low congenital parameters of neurotism) and more expressed stress both on psychological and physiological level in a greater degree than teenagers from family with mother and stepfather. Teenagers living in family with stepfather have parameters of anxiet similar to teenagers living in complete families.

  17. Effectiveness of mindfulness-based stress reduction on state/trait anxiety and quality of life in women with obesity

    Directory of Open Access Journals (Sweden)

    Asghar Jafari

    2017-04-01

    Full Text Available Background: Obesity affects the cognitive, emotional and behavioral functions and usually produces mood and anxiety disorders. The present study aimed to determine the effectiveness of mindfulness-based stress reduction (MBSR on promoting quality of life and decreasing anxiety among the obese women. Materials and Methods: In this pre-post-test designed experimental study with a 2 mouth follow- up, 24 obese women (BMI≥30 were randomly selected in the Obesity Treatment Center in (Tehran, Iran and assigned in Experimental and Control groups. Data were collected using the questionnaires of anxiety of Spiel-Berger (1970 and quality of life of Viyear (1988. The MBSR interventions of Kabat-Zinn were performed for experimental group in 8 sessions, followed by the assessment of anxiety and quality of life. Results: The pre- post-test and follow- up scores for quality of life of participants in MBSR program, in terms of general health; physical limitations; physical function; social function; state anxiety and trait anxiety were: (7.66±0.88, 9.50±1.67, 9.58±1.66; (22.83±1.58, 27.91±1.16, 27±1.53; (4.50±0.67, 6.16±1.11, 5±0.95; (2.91± 0.28, 5.91±0.66, 5.75±0.38; (52.25±3.51, 43.08±2.39, 44±2.29 and (68.08±1.78, 46.75±1.71, 47.25±2, respectively. The scores of quality of life was significantly increased in participants in MBSR compared to the Control group (P<0.01. In addition, the scores of state and trait anxiety were significantly decreased (P<0.01. Conclusion: The results of research provide some evidence to suggest that MBSR is an appropriate therapy for promoting quality of life and decreasing anxiety in obese women.

  18. NK cells link obesity-induced adipose stress to inflammation and insulin resistance.

    Science.gov (United States)

    Wensveen, Felix M; Jelenčić, Vedrana; Valentić, Sonja; Šestan, Marko; Wensveen, Tamara Turk; Theurich, Sebastian; Glasner, Ariella; Mendrila, Davor; Štimac, Davor; Wunderlich, F Thomas; Brüning, Jens C; Mandelboim, Ofer; Polić, Bojan

    2015-04-01

    An important cause of obesity-induced insulin resistance is chronic systemic inflammation originating in visceral adipose tissue (VAT). VAT inflammation is associated with the accumulation of proinflammatory macrophages in adipose tissue, but the immunological signals that trigger their accumulation remain unknown. We found that a phenotypically distinct population of tissue-resident natural killer (NK) cells represented a crucial link between obesity-induced adipose stress and VAT inflammation. Obesity drove the upregulation of ligands of the NK cell-activating receptor NCR1 on adipocytes; this stimulated NK cell proliferation and interferon-γ (IFN-γ) production, which in turn triggered the differentiation of proinflammatory macrophages and promoted insulin resistance. Deficiency of NK cells, NCR1 or IFN-γ prevented the accumulation of proinflammatory macrophages in VAT and greatly ameliorated insulin sensitivity. Thus NK cells are key regulators of macrophage polarization and insulin resistance in response to obesity-induced adipocyte stress.

  19. Stress corrosion cracking resistance of aluminum alloy 7000 series after two-step aging

    Directory of Open Access Journals (Sweden)

    Jegdić Bore V.

    2015-01-01

    Full Text Available The effect of one step-and a new (short two-step aging on the resistance to stress corrosion cracking of an aluminum alloy 7000 series was investigated, using slow strain rate test and fracture mechanics method. Aging level in the tested alloy was evaluated by means of scanning electron microscopy and measurements of electrical resistivity. It was shown that the alloy after the new two-step aging is significantly more resistant to stress corrosion cracking. Values of tensile properties and fracture toughness are similar for both thermal states. Processes that take place at the crack tip have been considered. The effect of the testing solution temperature on the crack growth rate on the plateau was determined. Two values of the apparent activation energy were obtained. These values correspond to different processes that control crack growth rate on the plateau at higher and lower temperatures. [Projekat Ministarstva nauke Republike Srbije, br. TR 34028 i br. TR 34016

  20. Joint Transcriptional Control of Virulence and Resistance to Antibiotic and Environmental Stress in Acinetobacter baumannii.

    Science.gov (United States)

    Gebhardt, Michael J; Gallagher, Larry A; Jacobson, Rachael K; Usacheva, Elena A; Peterson, Lance R; Zurawski, Daniel V; Shuman, Howard A

    2015-11-10

    The increasing emergence of antibiotic-resistant bacterial pathogens represents a serious risk to human health and the entire health care system. Many currently circulating strains of Acinetobacter baumannii exhibit resistance to multiple antibiotics. A key limitation in combating A. baumannii is that our understanding of the molecular mechanisms underlying the pathogenesis of A. baumannii is lacking. To identify potential virulence determinants of a contemporary multidrug-resistant isolate of A. baumannii, we used transposon insertion sequencing (TnSeq) of strain AB5075. A collection of 250,000 A. baumannii transposon mutants was analyzed for growth within Galleria mellonella larvae, an insect-based infection model. The screen identified 300 genes that were specifically required for survival and/or growth of A. baumannii inside G. mellonella larvae. These genes encompass both known, established virulence factors and several novel genes. Among these were more than 30 transcription factors required for growth in G. mellonella. A subset of the transcription factors was also found to be required for resistance to antibiotics and environmental stress. This work thus establishes a novel connection between virulence and resistance to both antibiotics and environmental stress in A. baumannii. Acinetobacter baumannii is rapidly emerging as a significant human pathogen, largely because of disinfectant and antibiotic resistance, causing lethal infection in fragile hosts. Despite the increasing prevalence of infections with multidrug-resistant A. baumannii strains, little is known regarding not only the molecular mechanisms that allow A. baumannii to resist environmental stresses (i.e., antibiotics and disinfectants) but also how these pathogens survive within an infected host to cause disease. We employed a large-scale genetic screen to identify genes required for A. baumannii to survive and grow in an insect disease model. While we identified many known virulence

  1. Impact of Pathogen Population Heterogeneity and Stress-Resistant Variants on Food Safety.

    Science.gov (United States)

    Abee, T; Koomen, J; Metselaar, K I; Zwietering, M H; den Besten, H M W

    2016-01-01

    This review elucidates the state-of-the-art knowledge about pathogen population heterogeneity and describes the genotypic and phenotypic analyses of persister subpopulations and stress-resistant variants. The molecular mechanisms underlying the generation of persister phenotypes and genetic variants are identified. Zooming in on Listeria monocytogenes, a comparative whole-genome sequence analysis of wild types and variants that enabled the identification of mutations in variants obtained after a single exposure to lethal food-relevant stresses is described. Genotypic and phenotypic features are compared to those for persistent strains isolated from food processing environments. Inactivation kinetics, models used for fitting, and the concept of kinetic modeling-based schemes for detection of variants are presented. Furthermore, robustness and fitness parameters of L. monocytogenes wild type and variants are used to model their performance in food chains. Finally, the impact of stress-resistant variants and persistence in food processing environments on food safety is discussed.

  2. Potential mechanisms for a role of metabolic stress in hypertrophic adaptations to resistance training.

    Science.gov (United States)

    Schoenfeld, Brad J

    2013-03-01

    It is well established that regimented resistance training can promote increases in muscle hypertrophy. The prevailing body of research indicates that mechanical stress is the primary impetus for this adaptive response and studies show that mechanical stress alone can initiate anabolic signalling. Given the dominant role of mechanical stress in muscle growth, the question arises as to whether other factors may enhance the post-exercise hypertrophic response. Several researchers have proposed that exercise-induced metabolic stress may in fact confer such an anabolic effect and some have even suggested that metabolite accumulation may be more important than high force development in optimizing muscle growth. Metabolic stress pursuant to traditional resistance training manifests as a result of exercise that relies on anaerobic glycolysis for adenosine triphosphate production. This, in turn, causes the subsequent accumulation of metabolites, particularly lactate and H(+). Acute muscle hypoxia associated with such training methods may further heighten metabolic buildup. Therefore, the purpose of this paper will be to review the emerging body of research suggesting a role for exercise-induced metabolic stress in maximizing muscle development and present insights as to the potential mechanisms by which these hypertrophic adaptations may occur. These mechanisms include increased fibre recruitment, elevated systemic hormonal production, alterations in local myokines, heightened production of reactive oxygen species and cell swelling. Recommendations are provided for potential areas of future research on the subject.

  3. Is osmotic adjustment required for water stress resistance in the Mediterranean shrub Atriplex halimus L?

    Science.gov (United States)

    Martìnez, Juan-Pablo; Lutts, Stanley; Schanck, André; Bajji, Mohammed; Kinet, Jean-Marie

    2004-09-01

    The effect of water stress was investigated in plants from two populations of Atriplex halimus L: Tensift issued from a salt-affected coastal area and Kairouan, originating from an inland dried site. Water deficit was applied by withholding water for 22 days. Shoot dry weight (shoot DW), leaf relative water content (RWC), turgid weight to dry weight ratio (TW/DW), osmotic potential (psis), osmotic adjustment (OA), proline, glycinebetaine, and sugar content were determined 1, 8, 15 and 22 days after withholding watering. Water stress induced a decrease in shoot DW, RWC, psis, and TW/DW, but an increase in glycinebetaine and sugar leaf contents. The decrease of psis and TW/DW was more marked in Kairouan than in Tensift. At the end of the stress period, Kairouan showed a greater OA compared with Tensift. However, the contribution of net solute accumulation (OAacc) was similar in both populations in response to stress. Water stress resistance could thus not be associated with higher OA, although the ability of plants to regulate these metabolic and physiological functions could play an important role under harmful conditions. The possible roles of osmolyte accumulations are discussed in relation to the specific physiological strategy of water-stress-resistance in this species.

  4. Mitochondrial function and energy metabolism in neuronal HT22 cells resistant to oxidative stress

    Science.gov (United States)

    Pfeiffer, Annika; Jaeckel, Martin; Lewerenz, Jan; Noack, Rebecca; Pouya, Alireza; Schacht, Teresa; Hoffmann, Christina; Winter, Jennifer; Schweiger, Susann; Schäfer, Michael K E; Methner, Axel

    2014-01-01

    Background and Purpose The hippocampal cell line HT22 is an excellent model for studying the consequences of endogenous oxidative stress. Extracellular glutamate depletes cellular glutathione by blocking the glutamate/cystine antiporter system xc−. Glutathione depletion induces a well-defined programme of cell death characterized by an increase in reactive oxygen species and mitochondrial dysfunction. Experimental Approach We compared the mitochondrial shape, the abundance of mitochondrial complexes and the mitochondrial respiration of HT22 cells, selected based on their resistance to glutamate, with those of the glutamate-sensitive parental cell line. Key Results Glutamate-resistant mitochondria were less fragmented and displayed seemingly contradictory features: mitochondrial calcium and superoxide were increased while high-resolution respirometry suggested a reduction in mitochondrial respiration. This was interpreted as a reverse activity of the ATP synthase under oxidative stress, leading to hydrolysis of ATP to maintain or even elevate the mitochondrial membrane potential, suggesting these cells endure ineffective energy metabolism to protect their membrane potential. Glutamate-resistant cells were also resistant to oligomycin, an inhibitor of the ATP synthase, but sensitive to deoxyglucose, an inhibitor of hexokinases. Exchanging glucose with galactose rendered resistant cells 1000-fold more sensitive to oligomycin. These results, together with a strong increase in cytosolic hexokinase 1 and 2, a reduced lactate production and an increased activity of glucose-6-phosphate dehydrogenase, suggest that glutamate-resistant HT22 cells shuttle most available glucose towards the hexose monophosphate shunt to increase glutathione recovery. Conclusions and Implications These results indicate that mitochondrial and metabolic adaptations play an important role in the resistance of cells to oxidative stress. Linked Articles This article is part of a themed issue on

  5. Effects of stress by unfamiliar sounds on carcass and meat traits in bulls from three continental beef cattle breeds at different ageing times.

    Science.gov (United States)

    Peña, F; Avilés, C; Domenech, V; González, A; Martínez, A; Molina, A

    2014-12-01

    One-hundred-and-twenty-four young bulls of three Continental beef cattle breeds were used to study the effect of pre-slaughter stress by unfamiliar sounds on carcass traits and quality characteristics of beef aged for three different periods. Stress due to unfamiliar noises had a moderately negative effect on carcass and meat quality. Carcasses from group Stressed had higher (Peffect on chromatic variables, WBSF and pressure losses. The cooking losses were not significantly affected by any of the three factors discussed. These results emphasize the importance of implementing appropriate management practices during pre-slaughter handling of cattle in order to reduce any possible risk factor for stress, as well as the different sensitivity of the breeds to similar stimuli. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Endogenous cytokinin overproduction modulates ROS homeostasis and decreases salt stress resistance in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Yanping eWang

    2015-11-01

    Full Text Available Cytokinins in plants are crucial for numerous biological processes, including seed germination, cell division and differentiation, floral initiation and adaptation to abiotic stresses. The salt stress can promote reactive oxygen species (ROS production in plants which are highly toxic and ultimately results in oxidative stress. However, the correlation between endogenous cytokinin production and ROS homeostasis in responding to salt stress is poorly understood. In this study, we analyzed the correlation of overexpressing the cytokinin biosynthetic gene AtIPT8 (adenosine phosphate-isopentenyl transferase 8 and the response of salt stress in Arabidopsis. Overproduction of cytokinins, which was resulted by the inducible overexpression of AtIPT8, significantly inhibited the primary root growth and true leaf emergence, especially under the conditions of exogenous salt, glucose and mannitol treatments. Upon cytokinin overproduction, the salt stress resistance was declined, and resulted in less survival rates and chlorophyll content. Interestingly, ROS production was obviously increased with the salt treatment, accompanied by endogenously overproduced cytokinins. The activities of CAT and SOD, which are responsible for scavenging ROS, were also affected. Transcription profiling revealed that the differential expressions of ROS-producing and scavenging related genes, the photosynthesis-related genes and stress responsive genes were existed in transgenic plants of overproducing cytokinins. Our results suggested that broken in the homeostasis of cytokinins in plant cells could modulate the salt stress responses through a ROS-mediated regulation in Arabidopsis.

  7. Neuroticism-related personality traits are associated with posttraumatic stress after abortion: findings from a Swedish multi-center cohort study.

    Science.gov (United States)

    Wallin Lundell, Inger; Sundström Poromaa, Inger; Ekselius, Lisa; Georgsson, Susanne; Frans, Örjan; Helström, Lotti; Högberg, Ulf; Skoog Svanberg, Agneta

    2017-10-02

    Most women who choose to terminate a pregnancy cope well following an abortion, although some women experience severe psychological distress. The general interpretation in the field is that the most consistent predictor of mental disorders after induced abortion is the mental health issues that women present with prior to the abortion. We have previously demonstrated that few women develop posttraumatic stress disorder (PTSD) or posttraumatic stress symptoms (PTSS) after induced abortion. Neuroticism is one predictor of importance for PTSD, and may thus be relevant as a risk factor for the development of PTSD or PTSS after abortion. We therefore compared Neuroticism-related personality trait scores of women who developed PTSD or PTSS after abortion to those of women with no evidence of PTSD or PTSS before or after the abortion. A Swedish multi-center cohort study including six Obstetrics and Gynecology Departments, where 1294 abortion-seeking women were included. The Screen Questionnaire-Posttraumatic Stress Disorder (SQ-PTSD) was used to evaluate PTSD and PTSS. Measurements were made at the first visit and at three and six month after the abortion. The Swedish universities Scales of Personality (SSP) was used for assessment of Neuroticism-related personality traits. Multiple logistic regression analyses were performed to investigate the risk factors for development of PTSD or PTSS post abortion. Women who developed PTSD or PTSS after the abortion had higher scores than the comparison group on several of the personality traits associated with Neuroticism, specifically Somatic Trait Anxiety, Psychic Trait Anxiety, Stress Susceptibility and Embitterment. Women who reported high, or very high, scores on Neuroticism had adjusted odds ratios for PTSD/PTSS development of 2.6 (CI 95% 1.2-5.6) and 2.9 (CI 95% 1.3-6.6), respectively. High scores on Neuroticism-related personality traits influence the risk of PTSD or PTSS post abortion. This finding supports the argument

  8. Influence of the clay in the stress cracking resistance of PET; Influencia de silicatos em camadas na resistencia ao 'stress cracking' do PET

    Energy Technology Data Exchange (ETDEWEB)

    Teofilo, Edvania T. [Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais, Universidade Federal de Campina Grande, PB (Brazil); Silva, Emanuela S.; Silva, Suedina M.L.; Rabello, Marcelo S., E-mail: marcelo@dema.ufcg.edu.b [Unidade Academica de Engenharia de Materiais, Universidade Federal de Campina Grande, PB (Brazil)

    2011-07-01

    The environmental stress cracking resistance in PET and hybrid PET/clay were conducted under stress relaxation test. X-ray diffraction analysis show that was obtained immiscible system. In the absence of aggressive fluids the hybrid exhibited higher relaxation rates than the PET. Already in contact with aggressive fluids showed a similar or lower relaxation rate than the PET, being more resistant. Suggesting that the clay, though not interlayer, interferes with the distribution of the stress cracking agent. Thus, the barrier effect caused by the clay was more significant than the stress concentration caused by it. (author)

  9. Associations of biochemical changes and maternal traits with mutation 1843 (C>T) in the RYR1 gene as a common cause for porcine stress syndrome.

    Science.gov (United States)

    Popovski, Z T; Tanaskovska, B; Miskoska-Milevska, E; Andonov, S; Domazetovska, S

    2016-12-01

    Stress syndrome is usually caused by a mutation in the ryanodine receptor gene (ryr1) and it is widely studied in humans and swine populations. The protein product of this gene plays a crucial role in the regulation of calcium transport in muscle cells. A G>T mutation in the human ryr1 gene, which results in the replacement of a conserved arginine at position 614 where a leucine occurs at the same position as the previously identified Arg→Cys mutation reported in all cases of porcine stress syndrome (PSS). Porcine stress syndrome affects biochemical pathways in stress-susceptible individuals during a stress episode and some biochemical parameters that were used as markers for diagnostic purposes. Also, PSS has remarkable influence on the maternal characteristics of sows. This study dealt with different genotypes for PSS and its association with possible biochemical changes and maternal traits of sows. Seventy-three reproductive sows genotyped for PSS by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) were included in this survey. Sixty of them were stress-free (NN), 11 were heterozygous carriers (Nn) and two animals were homozygous (nn) for the 1843 (C>T) mutation. Significant differences in non stress induced animals with different PSS genotypes were found in the values of creatine phoshokinase (CPK), lactate dehydrogenase (LDH), alkaline phosphatase (AP) and aspartate aminotransferase (AST). Regarding the maternal traits, our study showed that stress susceptible animals (nn) have an increased number of stillborn piglets and a reduced number of newborn piglets compared with heterozygous and normal animals.

  10. Associations of biochemical changes and maternal traits with mutation 1843 (C>T in the RYR1 gene as a common cause for porcine stress syndrome

    Directory of Open Access Journals (Sweden)

    Popovski ZT

    2016-12-01

    Full Text Available Stress syndrome is usually caused by a mutation in the ryanodine receptor gene (ryr1 and it is widely studied in humans and swine populations. The protein product of this gene plays a crucial role in the regulation of calcium transport in muscle cells. A G>T mutation in the human ryr1 gene, which results in the replacement of a conserved arginine at position 614 where a leucine occurs at the same position as the previously identified Arg→Cys mutation reported in all cases of porcine stress syndrome (PSS. Porcine stress syndrome affects biochemical pathways in stress-susceptible individuals during a stress episode and some biochemical parameters that were used as markers for diagnostic purposes. Also, PSS has remarkable influence on the maternal characteristics of sows. This study dealt with different genotypes for PSS and its association with possible biochemical changes and maternal traits of sows. Seventy-three reproductive sows genotyped for PSS by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP were included in this survey. Sixty of them were stress-free (NN, 11 were heterozygous carriers (Nn and two animals were homozygous (nn for the 1843 (C>T mutation. Significant differences in non stress induced animals with different PSS genotypes were found in the values of creatine phoshokinase (CPK, lactate dehydrogenase (LDH, alkaline phosphatase (AP and aspartate aminotransferase (AST. Regarding the maternal traits, our study showed that stress susceptible animals (nn have an increased number of stillborn piglets and a reduced number of newborn piglets compared with heterozygous and normal animals.

  11. Dissecting the sea wheatgrass genome to transfer biotic stress resistance and abiotic stress tolerance into wheat

    Science.gov (United States)

    Wheat production is facing numerous challenges from biotic and abiotic stresses. Alien gene transfer has been an effective approach for wheat germplasm enhancement. Sea wheatgrass (SWG) (Thinopyrum junceiforme, 2n = 4x = 28, genomes J1J1J2J2) is a distant relative of wheat and a relatively untapped ...

  12. Electrical resistivity change in amorphous Ta42Si13N45 films by stress relaxation

    Science.gov (United States)

    Nicolet, M.-A.; Ryser, M.; Romano, V.

    2015-03-01

    In a first experiment, a reactively sputtered amorphous Ta42Si13N45 film about 260 nm thick deposited on a flat and smooth alumina substrate was thermally annealed in air for 30 min and let cooled again repeatedly at successively higher temperatures from 200 to 500 °C. This treatment successively and irreversibly increases the room temperature resistivity of the film monotonically from its initial value of 670 μΩ cm to a maximum of 705 μΩ cm (+5.2 %). Subsequent heat treatments at temperatures below 500 °C and up to 6 h have no further effect on the room temperature resistivity. The new value remains unchanged after 3.8 years of storage at room temperature. In a second experiment, the evolution of the initially compressive stress of a film similarly deposited by reactive sputtering on a 2-inch silicon wafer was measured by tracking the wafer curvature during similar thermal annealing cycles. A similar pattern of irreversible and reversible changes of stress was observed as for the film resistivity. Transmission electron micrographs and secondary ion mass profiles of the film taken before and after thermal annealing in air establish that both the structure and the composition of the film scarcely change during the annealing cycles. We reason that the film stress is implicated in the resistivity change. In particular, to interpret the observations, a model is proposed where the interface between the film and the substrate is mechanically unyielding.

  13. Methuselah-like genes affect development, stress resistance, lifespan and reproduction in Tribolium castaneum.

    Science.gov (United States)

    Li, Chengjun; Zhang, Yi; Yun, Xiaopei; Wang, Yanyun; Sang, Ming; Liu, Xing; Hu, Xingxing; Li, Bin

    2014-10-01

    Methuselah (Mth) is associated with lifespan, stress resistance and reproduction in Drosophila melanogaster, but Mth is not present in nondrosophiline insects. A number of methuselah-likes (mthls) have been identified in nondrosophiline insects, but it is unknown whether the functions of mth are shared by mthls or are divergent from them. Five mthls have been identified in Tribolium castaneum. Although they have different developmental expression patterns, they all enhance resistance to starvation. Only mthl1 and mthl2 enhance resistance to high temperature, whereas mthl4 and mthl5 negatively regulate oxidative stress in T. castaneum. Unlike in the fly with mth mutation, knockdown of mthls, except mthl3, shortens the lifespan of T. castaneum. Moreover, mthl1 and mthl2 are critical for Tribolium development. mthl1 plays important roles in larval and pupal development and adult eclosion, while mthl2 is required for eclosion. Moreover, mthl1 and mthl2 silencing reduces the fertility of T. castaneum, and mthl1 and mthl4 are also essential for embryo development. In conclusion, mthls have a significant effect on insect development, lifespan, stress resistance and reproduction. These results provide experimental evidence for functional divergence among mthls/mth and clues for the signal transduction of Mthls. © 2014 The Royal Entomological Society.

  14. The Effect of Water Stress and Polymer on Water Use Efficiency, Yield and several Morphological Traits of Sunflower under Greenhouse Condition

    Directory of Open Access Journals (Sweden)

    Hossein NAZARLI

    2010-12-01

    Full Text Available In many part of Iran, the reproductive growth stages of sunflower (Helianthus annuus L. are exposed to water deficit stress. Therefore, the investigation of irrigation management in the farm conditions is a necessary element for increasing irrigation efficiency and decreasing water losses. The objective of present study was to investigate the effect of different rates of super absorbent polymer and levels of water stress on water use efficiency (WUE, yield and some morphological traits of sunflower (cultivar Master. Factorial experiment was carried out in completely randomized design with 3 replications. Factors were water stress in three levels (irrigation in 0.75; 0.50 and 0.25% of field capacity and super absorbent polymer in five levels (0; 0.75; 0.150; 2.25; 3 g/kg of soil. Super absorbent polymer was added in eight leaves stage of sunflower to pots in deepness of roots development. Water stress treatment was also applied in this growth stage of sunflower. For stress application, pots were weighted every day and irrigated when soil water received to 0.75; 0.50 and 0.25 of field capacity, respectively. The results of ANOVA indicated that the effect of different rates of super absorbent polymer and different rates of consumed water in all traits were significant. ANOVA also revealed that the interactive effects of two mentioned factors were significant except for seed yield trait. Polynomial model based on the ANOVA results was fitted for each trait. The results indicated that water stress significantly convert in decreasing the number of leaves per plant, chlorophyll content, 100 weight of seeds, seed yield and WUE in sunflower, whereas the application of super absorbent polymer moderated the negative effect of deficit irrigation, especially in high rates of polymer (2.25 and 3 g/kg of soil. The above mentioned rates of polymer have the best effect to all characteristics of sunflower in all levels of water stress treatment. The findings

  15. Molecular Events Linking Oxidative Stress and Inflammation to Insulin Resistance and β-Cell Dysfunction

    Science.gov (United States)

    Keane, Kevin Noel; Cruzat, Vinicius Fernandes; Carlessi, Rodrigo; de Bittencourt, Paulo Ivo Homem; Newsholme, Philip

    2015-01-01

    The prevalence of diabetes mellitus (DM) is increasing worldwide, a consequence of the alarming rise in obesity and metabolic syndrome (MetS). Oxidative stress and inflammation are key physiological and pathological events linking obesity, insulin resistance, and the progression of type 2 DM (T2DM). Unresolved inflammation alongside a “glucolipotoxic” environment of the pancreatic islets, in insulin resistant pathologies, enhances the infiltration of immune cells which through secretory activity cause dysfunction of insulin-secreting β-cells and ultimately cell death. Recent molecular investigations have revealed that mechanisms responsible for insulin resistance associated with T2DM are detected in conditions such as obesity and MetS, including impaired insulin receptor (IR) signalling in insulin responsive tissues, oxidative stress, and endoplasmic reticulum (ER) stress. The aim of the present review is to describe the evidence linking oxidative stress and inflammation with impairment of insulin secretion and action, which result in the progression of T2DM and other conditions associated with metabolic dysregulation. PMID:26257839

  16. Determination of survival, identity and stress resistance of probiotic bifidobacteria in bio-yoghurts.

    Science.gov (United States)

    Jayamanne, V S; Adams, M R

    2006-03-01

    To determine the level of bifidobacteria in bio-yoghurts in the UK, identify the species, and compare the resistance of common Bifidobacterium spp. to acidity and oxidative stress. A storage trial of bio-yoghurts was carried out to determine the level and survival of bifidobacteria. The 16S rRNA gene targeted PCR was used to identify the species. Acid tolerance was determined by introducing the organisms to pH-adjusted skimmed milk and enumerating during storage at 4 degrees C. Oxidative stress resistance was determined using the H(2)O(2) disc diffusion assay technique. Nine of 10 bio-yoghurts contained bifidobacteria at levels >10(6) CFU g(-1) at the time of purchase. The viability of the organism decreased during storage and on expiry only five products retained viability >10(6) CFU g(-1) while two others were very close to the target population. Bifidobacterium animalis ssp. lactis showed superior survival abilities and stress tolerance compared with Bifidobacterium longum, Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium adolescentis and Bifidobacterium longum biotype infantis. Bifidobacterium animalis ssp. lactis, the only Bifidobacterium spp. found in bio-yoghurts, had the greatest resistance to acidity and oxidative stress. The technological properties of B. animalis ssp. lactis make it suitable for inclusion in bio-yoghurts although its putative health benefits need further investigation.

  17. Diet-induced obesity induces endoplasmic reticulum stress and insulin resistance in the amygdala of rats.

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    Castro, Gisele; C Areias, Maria Fernanda; Weissmann, Lais; Quaresma, Paula G F; Katashima, Carlos K; Saad, Mario J A; Prada, Patricia O

    2013-01-01

    Insulin acts in the hypothalamus, decreasing food intake (FI) by the IR/PI3K/Akt pathway. This pathway is impaired in obese animals and endoplasmic reticulum (ER) stress and low-grade inflammation are possible mechanisms involved in this impairment. Here, we highlighted the amygdala as an important brain region for FI regulation in response to insulin. This regulation was dependent on PI3K/AKT pathway similar to the hypothalamus. Insulin was able to decrease neuropeptide Y (NPY) and increase oxytocin mRNA levels in the amygdala via PI3K, which may contribute to hypophagia. Additionally, obese rats did not reduce FI in response to insulin and AKT phosphorylation was decreased in the amygdala, suggesting insulin resistance. Insulin resistance was associated with ER stress and low-grade inflammation in this brain region. The inhibition of ER stress with PBA reverses insulin action/signaling, decreases NPY and increases oxytocin mRNA levels in the amygdala from obese rats, suggesting that ER stress is probably one of the mechanisms that induce insulin resistance in the amygdala.

  18. Effect of Myricetin, Pyrogallol, and Phloroglucinol on Yeast Resistance to Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Vanda Mendes

    2015-01-01

    Full Text Available The health beneficial effects of dietary polyphenols have been attributed to their intrinsic antioxidant activity, which depends on the structure of the compound and number of hydroxyl groups. In this study, the protective effects of pyrogallol, phloroglucinol, and myricetin on the yeast Saccharomyces cerevisiae were investigated. Pyrogallol and myricetin, which have a pyrogallol structure in the B ring, increased H2O2 resistance associated with a reduction in intracellular oxidation and protein carbonylation, whereas phloroglucinol did not exert protective effects. The acquisition of oxidative stress resistance in cells pretreated with pyrogallol and myricetin was not associated with an induction of endogenous antioxidant defences as assessed by the analysis of superoxide dismutase and catalase activities. However, myricetin, which provided greater stress resistance, prevented H2O2-induced glutathione oxidation. Moreover, myricetin increased the chronological lifespan of yeast lacking the mitochondrial superoxide dismutase (Sod2p, which exhibited a premature aging phenotype and oxidative stress sensitivity. These findings show that the presence of hydroxyl groups in the ortho position of the B ring in pyrogallol and myricetin contributes to the antioxidant protection afforded by these compounds. In addition, myricetin may alleviate aging-induced oxidative stress, particularly when redox homeostasis is compromised due to downregulation of endogenous defences present in mitochondria.

  19. Inclusion of copepod Acartia tonsa nauplii in the feeding of Centropomus undecimalis larvae increases stress resistance

    Directory of Open Access Journals (Sweden)

    Wanessa de Melo-Costa

    2015-09-01

    Full Text Available This research represents the first result of studies of the common snook Centropomus undecimalis larvae from broodstock matured in captivity in Brazil. The aim of this study was to evaluate if the inclusion of Acartia tonsa nauplii improves stress resistance of common snook larvae. The larvae were fed with: rotifers Brachionus plicatilis (10 to 15 mL-1; A. tonsa nauplii (0.25 to 0.5 mL-1 and rotifers (5 to 7.5 mL-1, and A. tonsa nauplii (0.12 to 0.25 mL-1. The average percentage of survival of the treatments was 11.9%. At 20 days of age, larvae were subjected to thermal stress. Subsequently, the stress resistance was evaluated. Common snook larvae fed B. plicatilis+A. tonsa reached a higher weight and length (7.5 ± 0.00 mg and 9.1 ± 0.23 mm, respectively and resisted more heat stress (87.4% than larvae fed other foods, indicating that the feed mixture is satisfactory as a starter diet for larvae of common snook. However, more research is needed to confirm these results.

  20. Association of Oxidative Stress and Obesity with Insulin Resistance in Type 2 Diabetes Mellitus.

    Science.gov (United States)

    Das, P; Biswas, S; Mukherjee, S; Bandyopadhyay, S K

    2016-01-01

    Oxidative stress occurs due to delicate imbalance between pro-oxidant and anti oxidant forces in our system. It has been found to be associated with many morbidities but its association with obesity and insulin resistance is still controversial. Here in our study we examined 167 patients of recent onset type 2 diabetes mellitus and 60 age sex matched non-diabetic control. Body Mass Index (BMI), abdominal circumference, fasting blood glucose, serum insulin and plasma Malondealdehyde (MDA, marker for oxidative stress) were measured in them. On the basis of BMI, subjects were divided into obese (BMI≥25) and non obese (BMIobese and non-obese sub groups. Insulin resistance score showed positive correlation with BMI, abdominal circumference, and plasma MDA, strength of association being highest with abdominal circumference. Plasma MDA was found to have positive correlation with physical parameters. Study concludes that, obesity mainly central type may predispose to insulin resistance and oxidative stress may be a crucial factor in its pathogenesis. Thus, oxidative stress may be the connecting link between obesity and type 2 diabetes mellitus, two on going global epidemics.