Plant-pathogen interactions: toward development of next-generation disease-resistant plants

Briskly evolving phytopathogens are dire threats to our food supplies and threaten global food security. From the recent advances made toward high-throughput sequencing technologies, understanding of pathogenesis and effector biology, and plant innate immunity, translation of these means into new control tools is being introduced to develop durable disease resistance. Effectoromics as a powerful genetic tool for uncovering effector-target genes, both susceptibility genes and executor resistance genes in effector-assisted breeding, open up new avenues to improve resistance. TALENs (Transcription Activator-Like Effector Nucleases), engineered nucleases and CRISPR (Clustered Regulatory Interspaced Short Palindromic Repeats)/Cas9 systems are breakthrough and powerful techniques for genome editing, providing efficient mechanisms for targeted crop protection strategies in disease resistance programs. In this review, major advances in plant disease management to confer durable disease resistance and novel strategies for boosting plant innate immunity are highlighted.

Risk assessment and preventive strategies for herbicide resistance in NR (phase III)

The threat and management of glyphosate# resistant weeds are major issues facing northern region growers. At present five weeds are confirmed glyphosate-resistant: barnyard grass, liverseed grass, windmill grass, annual ryegrass and flaxleaf fleabane. This project used 25 experiments to investigate the ecology of the grass weeds, plus new or improved chemical and non-chemical control tactics for them. The refined glyphosate resistance model developed in this project used the experiments' findings to predict the long-term impacts on evolution of resistance and on seed bank numbers of resistant weeds. These data led to revised management and resistance avoidance strategies, which were published in the Reporter newsletter, and via an on-line risk assessment tool. - See more at: http://finalreports.grdc.com.au/UQ00054#sthash.oTkCN4Sk.dpuf

Implementing technologies and strategies to maintain resistance to sunflower rust

This project proposes to implement resistance gene pyramiding strategies through close collaboration with Pacific Seeds. These strategies have been developed by Department of Primary Industries and Fisheries (DPI&F) researchers in two previous GRDC projects, DAQ356 and DAQ537. The gene pyramids will be incorporated into elite breeding material using techniques and technologies developed by DPI&F. These include the use of DNA markers. If successful, a range of elite lines/commercial hybrids containing strategic resistance gene pyramids will be available to growers. These lines will provide the industry with a directed strategy to manage the sunflower rust pathogen and reduce the risk of outbreaks of the disease.

Impact of resistance exercise on ribosome biogenesis is acutely regulated by post-exercise recovery strategies

Muscle hypertrophy occurs following increased protein synthesis, which requires activation of the ribosomal complex. Additionally, increased translational capacity via elevated ribosomal RNA (rRNA) synthesis has also been implicated in resistance training-induced skeletal muscle hypertrophy. The time course of ribosome biogenesis following resistance exercise (RE) and the impact exerted by differing recovery strategies remains unknown. In the present study, the activation of transcriptional regulators, the expression levels of pre-rRNA, and mature rRNA components were measured through 48 h after a single-bout RE. In addition, the effects of either low-intensity cycling (active recovery, ACT) or a cold-water immersion (CWI) recovery strategy were compared. Nine male subjects performed two bouts of high-load RE randomized to be followed by 10 min of either ACT or CWI. Muscle biopsies were collected before RE and at 2, 24, and 48 h after RE. RE increased the phosphorylation of the p38-MNK1-eIF4E axis, an effect only evident with ACT recovery. Downstream, cyclin D1 protein, total eIF4E, upstream binding factor 1 (UBF1), and c-Myc proteins were all increased only after RE with ACT. This corresponded with elevated abundance of the pre-rRNAs (45S, ITS-28S, ITS-5.8S, and ETS-18S) from 24 h after RE with ACT. In conclusion, coordinated upstream signaling and activation of transcriptional factors stimulated pre-rRNA expression after RE. CWI, as a recovery strategy, markedly blunted these events, suggesting that suppressed ribosome biogenesis may be one factor contributing to the impaired hypertrophic response observed when CWI is used regularly after exercise.

Going for the jugular : strategies of resistance in the fiction of Helena Maria Viramontes

O objetivo desta dissertação é analisar contos selecionados e o romance Under the Feet of Jesus da escritora chicana Helena María Viramontes, enfocando a apropriação de mitos astecas e lendas mexicanas protagonizados por figuras femininas, históricas ou míticas, como La Manlinche, La Llorona e The Hungry Woman. Esta re-visão crítica do passado tem um papel vital para as chicanas, reais e ficcionais, ao enfrentarem o domínio patriarcal, colonial e neocolonial. Devido à complexidade gerada pela ausência de linearidade narrativa, tanto nos contos como no romance, tornou-se necessária uma breve análise das estratégias narrativas a fim de ilustrar como tais estratégias estão intrinsecamente ligadas à apresentação fragmentada da vida dos trabalhadores migrantes. Foi igualmente indispensável examinar as demais práticas narrativas da autora tais como focalização, desconstrução, simultaneidade e justaposição, assim como o elo, por ela proposto em Under the Feet of Jesus, entre leitura, identidade, e engajamento com o mundo para promover a transformação social

Non-genetic mechanisms communicating antibiotic resistance:rethinking strategies for antimicrobial drug design

Introduction: Infections by multidrug-resistant bacteria are of great concern worldwide. In many cases, resistance is not due to the presence of specific antibiotic-modifying enzymes, but rather associated with a general impermeability of the bacterial cell envelope. The molecular bases of this intrinsic resistance are not completely understood. Moreover, horizontal gene transfers cannot solely explain the spread of intrinsic resistance among bacterial strains. Areas covered: This review focuses on the increased intrinsic antibiotic resistance mediated by small molecules. These small molecules can either be secreted from bacterial cells of the same or different species (e.g., indole, polyamines, ammonia, and the Pseudomonas quinolone signal) or be present in the bacterial cell milieu, whether in the environment, such as indole acetic acid and other plant hormones, or in human tissues and body fluids, such as polyamines. These molecules are metabolic byproducts that act as infochemicals and modulate bacterial responses toward antibiotics leading to increasing or decreasing resistance levels. Expert opinion: The non-genetic mechanisms of antibiotic response modulation and communication discussed in this review should reorient our thinking of the mechanisms of intrinsic resistance to antibiotics and its spread across bacterial cell populations. The identification of chemical signals mediating increased intrinsic antibiotic resistance will expose novel critical targets for the development of new antimicrobial strategies.

Flexible energetics of cheetah hunting strategies provide resistance against kleptoparasitism

Population viability is driven by individual survival, which in turn depends on individuals balancing energy budgets. As carnivores may function close to maximum sustained power outputs, decreased food availability or increased activity may render some populations energetically vulnerable. Prey theft may compromise energetic budgets of mesopredators, such as cheetahs and wild dogs, which are susceptible to competition from larger carnivores. We show that daily energy expenditure (DEE) of cheetahs was similar to size-based predictions and positively related to distance traveled. Theft at 25% only requires cheetahs to hunt for an extra 1.1 hour per day, increasing DEE by just 12%. Therefore, not all mesopredators are energetically constrained by direct competition. Other factors that increase DEE, such as those that increase travel, may be more
important for population viability.

Molecular strategies for genetic diversity analysis and development of markers linked to resistance traits in apple

The goal of many plant scientists’ research is to explain natural phenotypic variation in term of simple changes in DNA sequence. DNA-based molecular markers are extensively used for the construction of genome-wide molecular maps and to perform genetic analysis for simple and complex traits. The PhD thesis was divided into two main research lines according to the different approaches adopted. The first research line is to analyze the genetic diversity in an Italian apple germplasm collection for the identification of markers tightly linked to targeted genes by an association genetic method. This made it possible to identify synomym and homonym accessions and triploids. The fruit red skin color trait has been used to test the reliability of the genetic approaches in this species. The second line is related to the development of molecular markers closely linked to the Rvi13 and Rvi5 scab resistance genes, previously mapped on apple’s chromosome 10 and 17 respectively by using the traditional linkage mapping method. Both region have been fine-mapped with various type of markers that could be used for marker-assisted selection in future breeding programs and to isolate the two resistance genes.

Strategies of Representation, Relationship, and Resistance: British Women Travelers and Mormon Plural Wives, c. 1870-1890

During the 1870s and 1880s, several British women writers traveled by transcontinental railroad across the American West via Salt Lake City, Utah, the capital of the Church of Jesus Christ of Latter-day Saints, or Mormons. These women subsequently wrote books about their travels for a home audience with a taste for adventures in the American West, and particularly for accounts of Mormon plural marriage, which was sanctioned by the Church before 1890. "The plight of the Mormon woman," a prominent social reform and literary theme of the period, situated Mormon women at the center of popular representations of Utah during the second half of the nineteenth century. "The Mormon question" thus lends itself to an analysis of how a stereotyped subaltern group was represented by elite British travelers. These residents of western American territories, however, differed in important respects from the typical subaltern subjects discussed by Victorian travelers. These white, upwardly mobile, and articulate Mormon plural wives attempted to influence observers' representations of them through a variety of narrative strategies. Both British women travel writers and Mormon women wrote from the margins of power and credibility, and as interpreters of the Mormon scene were concerned to established their representational authority.

Toward an effective strategy in glioblastoma treatment. Part I: resistance mechanisms and strategies to overcome resistance of glioblastoma to temozolomide.

International audience

Screening, isolation, and decolonisation strategies in the control of meticillin resistant Staphylococcus aureus in intensive care units : cost effectiveness evaluation

Objective: To assess the cost-effectiveness of screening, isolation and decolonisation strategies in the control of methicillin-resistant Staphylococcus aureus (MRSA) in intensive care units (ICUs). Design: Economic evaluation. Setting: England and Wales. Population: ICU patients. Main outcome measures: Infections, deaths, costs, quality adjusted life years (QALYs), incremental cost-effectiveness ratios for alternative strategies, net monetary benefits (NMBs). Results: All strategies using isolation but not decolonisation improved health outcomes but increased costs. When MRSA prevalence on admission to the ICU was 5% and the willingness to pay per QALY gained was between £20,000 and £30,000, the best such strategy was to isolate only those patients at high risk of carrying MRSA (either pre-emptively or following identification by admission and weekly MRSA screening using chromogenic agar). Universal admission and weekly screening using polymerase chain reaction (PCR)-based MRSA detection coupled with isolation was unlikely to be cost-effective unless prevalence was high (10% colonised with MRSA on admission to the ICU). All decolonisation strategies improved health outcomes and reduced costs. While universal decolonisation (regardless of MRSA status) was the most cost-effective in the short-term, strategies using screening to target MRSA carriers may be preferred due to reduced risk of selecting for resistance. Amongst such targeted strategies, universal admission and weekly PCR screening coupled with decolonisation with nasal mupirocin was the most cost-effective. This finding was robust to ICU size, MRSA admission prevalence, the proportion of patients classified as high-risk, and the precise value of willingness to pay for health benefits. Conclusions: MRSA control strategies that use decolonisation are likely to be cost-saving in an ICU setting provided resistance is lacking, and combining universal PCR-based screening with decolonisation is likely to represent good value for money if untargeted decolonisation is considered unacceptable. In ICUs where decolonisation is not implemented there is insufficient evidence to support universal MRSA screening outside high prevalence settings.