Transformation and regeneration of the holoparasitic plant Phelipanche aegyptiaca

<p>Abstract</p> <p>Background</p> <p>Transformation and subsequent regeneration of holoparasitic plants has never been reported, in part due to challenges in developing transformation protocols, but also because regeneration of obligate parasites is difficult since their survival depends completely on successful haustorium penetration of a host and the formation of vascular connections. The recent completion of a massive transcriptome sequencing project (the Parasitic Plant Genome Project) will fuel the use of genomic tools for studies on parasitic plants. A reliable system for holoparasite transformation is needed to realize the full value of this resource for reverse genetics and functional genomics studies.</p> <p>Results</p> <p>Here we demonstrate that transformation of <it>Phelipanche aegyptiaca </it>is achieved by infection of 3 month-old <it>in vitro </it>grown <it>P. aegyptiaca </it>calli with <it>Agrobacterium rhizogenes </it>harboring the yellow fluorescent protein (YFP). Four months later, YFP-positive regenerated calli were inoculated onto tomato plants growing in a minirhizotron system. Eight days after inoculation, transgenic parasite tissue formed lateral haustoria that penetrated the host and could be visualized under UV illumination through intact host root tissue. YFP-positive shoot buds were observed one month after inoculation.</p> <p>Conclusions</p> <p>This work constitutes a breakthrough in holoparasitic plant research methods. The method described here is a robust system for transformation and regeneration of a holoparasitic plant and will facilitate research on unique parasitic plant capabilities such as host plant recognition, haustorial formation, penetration and vascular connection.</p

A revised classification of temperate lowland groundwater‐fed headwater streams based on their flora

Prolonged drought leads to the temporary simplification or loss of aquatic biological communities, as surface water is progressively reduced or dry phases are extended in intermittent streams. Using surveys of aquatic and semi‐aquatic plants, and recording non‐aquatic grasses and herbs, we classify the communities within 24 groundwater‐fed streams in south England. We examine changes over a 21‐year period following a 3‐year drought. Our classification reveals a simplification of communities driven by a decline in the abundance of obligate aquatic taxa and an increase in the abundance of semi‐aquatic taxa. We demonstrate plant community structure as a strong indicator of a site’s flow history, including intermittence, but interactions with channel morphology also influence communities and need further investigation. We recommend that future surveys encompass terrestrial, semi‐aquatic and aquatic plants, as well as habitat assessments, to improve the understanding of how instream communities change between flowing, ponded and dry phases in intermittent streams

An invertebrate-based index to characterize ecological responses to flow intermittence in rivers

Intermittent streams occur across global regions, and are increasingly recognized to support high bio-diversity and perform important ecological roles within catchments. New tools are needed to better characterize biotic responses to the full spectrum of environmental conditions that occur in these dynamic systems, because the biological indices developed to assess ecological responses to flow in perennial rivers may be inaccurate in intermittent streams. We present the Monitoring Intermittent Streams index (MIS-index), a new biological index that can be used to assess invertebrate responses to environmental changes spanning flowing, ponded and drying states. As well as fully aquatic taxa, the index includes semi-aquatic and terrestrial invertebrates from marginal habitats, which are collected during the standard surveys used by regulatory agencies to assess ecological quality. We explore how including these taxa within an index informs our understanding of aquatic–terrestrial invertebrate community responses to changing habitat composition, as intermittent streams transition from lotic to lentic then drier conditions. We explain the development of the MIS-index and explore its performance compared with other indices. We suggest index combinations that can be used to detect different aspects of ecological responses to variation in instream conditions, and highlight the advantages of including semi-aquatic and terrestrial taxa. We call for researchers to test the performance of the MIS-index across a wide range of intermittent stream types, to enable its development into an internationally applicable tool for the holistic assessment of ecological responses to changing hydrological conditions including drying

A comparison of biotic groups as dry-phase indicators of ecological quality in intermittent rivers and ephemeral streams

Intermittent rivers and ephemeral streams (IRES) are dynamic ecosystems that shift between aquatic and terrestrial states. IRES are widespread, abundant and increasing in extent, but developing biomonitoring programmes to determine their ecological quality is challenging. To date, quality assessments have focused on the aquatic organisms present during wet phases, whereas dry-phase communities remain poorly characterized. We examined multiple biotic groups present in dry IRES channels, to compare assemblages at sites impacted and unimpacted by human activity and to evaluate the potential of each group as an ecological quality indicator. We explored existing, unpublished data for three biotic groups: an aquatic microflora (diatoms), an aquatic fauna (the invertebrate ‘seedbank’), and a mixed flora (aquatic and terrestrial plants); notably, we did not source data for terrestrial assemblages with high potential to act as indicators. Diatom and plant assemblage composition differed between impacted and unimpacted sites, and the latter assemblages were more diverse and included more indicator taxa. Invertebrate seedbank taxa richness was higher at unimpacted sites but compositional differences were not detected, probably due to the coarse taxonomic resolution to which abundant taxa were identified. Performance of standard indices of ecological quality was variable, but differences were identified between impacted and unimpacted conditions for all biotic groups. Our results can inform the enhancement of biomonitoring programmes designed to characterize IRES ecological quality in relation to legislative targets. We highlight the need to integrate wet- and dry-phase survey data in holistic quality assessments. Although we suggest diatoms, aquatic plants and the aquatic invertebrate seedbank as having the potential to inform assessment of dry-phase ecological quality, we highlight the need for research to further characterize these aquatic groups and, crucially, to explore terrestrial assemblages with high potential to act as dry-phase quality indicators

Faecal immunochemical tests (FIT) can help to rule out colorectal cancer in patients presenting in primary care with lower abdominal symptoms:a systematic review conducted to inform new NICE DG30 diagnostic guidance

__Background:__ This study has attempted to assess the effectiveness of quantitative faecal immunochemical tests (FIT) for triage of people presenting with lower abdominal symptoms, where a referral to secondary care for investigation of suspected colorectal cancer (CRC) is being considered, particularly when the 2-week criteria are not met. __Methods:__ We conducted a systematic review following published guidelines for systematic reviews of diagnostic tests. Twenty-one resources were searched up until March 2016. Summary estimates were calculated using a bivariate model or a random-effects logistic regression model. __Results:__ Nine studies are included in this review. One additional study, included in our systematic review, was provided as 'academic in confidence' and cannot be described herein. When FIT was based on a single faecal sample and a cut-off of 10 μg Hb/g faeces, sensitivity estimates indicated that a negative result using either the OC-Sensor or HM-JACKarc may be adequate to rule out nearly all CRC; the summary estimate of sensitivity for the OC-Sensor was 92.1%, based on four studies, and the only study of HM-JACKarc to assess the 10 μg Hb/g faeces cut-off reported a sensitivity of 100%. The corresponding specificity estimates were 85.8% (95% CI 78.3-91.0%) and 76.6%, respectively. When the diagnostic criterion was changed to include lower grades of neoplasia, i.e. the target condition included higher risk adenoma (HRA) as well as CRC, the rule-out performance of both FIT assays was reduced. __Conclusions:__ There is evidence to suggest that triage using FIT at a cut-off around 10 μg Hb/g faeces has the potential to correctly rule out CRC and avoid colonoscopy in 75-80% of symptomatic patients. Systematic review registration: PROSPERO 4201603772

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Alexithymia may explain the relationship between autistic traits and eating disorder psychopathology

Background: Autistic people are disproportionately vulnerable to anorexia nervosa and other eating disorders (ED), and within the general population, autistic traits correlate with ED psychopathology. A putative mechanism which may underpin this heightened risk is alexithymia, a difficulty identifying and describing emotional states which is observed in both autism and ED. In two experiments with independent non-clinical samples, we explored whether alexithymia might mediate the heightened risk of eating psychopathology in individuals high in autistic traits. Methods: Our first experiment used the PROCESS macro for SPSS to examine relationships between alexithymia (measured by the Toronto Alexithymia Scale (TAS-20)), autistic traits (autism quotient (AQ)), and eating psychopathology (Eating Attitudes Test (EAT-26)) in 121 participants. Our second experiment (n = 300) replicated and furthered this analysis by examining moderating effects of sex and controlling for anxiety and depression as covariates. We also included an additional performance-based measure of alexithymia, the Levels of Emotional Awareness Scale (LEAS). Results: Study 1 suggested that TAS-20 scores mediated the relationship between heightened autistic traits and eating psychopathology. Replication and further scrutiny of this finding, in study 2, revealed that this mediation effect was partial and specific to the female participants in this sample. The mediation effect appeared to be carried by the difficulty identifying feelings subscale of the TAS-20, even when depression and anxiety were controlled for. LEAS scores, however, were not significantly related to autistic traits or eating psychopathology. Limitations: Cross-sectional data prevents any conclusions around the direction and causality of relationships between alexithymia, autistic traits, and eating psychopathology (alongside depression and anxiety), necessitating longitudinal research. Our non-clinical sample was predominantly Caucasian undergraduate students, so it remains to be seen if these results would extrapolate to clinical and/or autistic samples. Divergence between the TAS-20 and LEAS raises crucial questions regarding the construct validity of these measures. Conclusions: Our findings with respect to autistic traits suggest that alexithymia could partially explain the prevalence of ED in autistic people and may as such be an important consideration in the pathogenesis and treatment of ED in autistic and non-autistic people alike. Further research with clinical samples is critical to explore these ideas. Differences between men and women, furthermore, emphasize the importance of looking for sexspecific as well as generic risk factors in autistic and non-autistic men and women

Factorial validity of the Toronto Alexithymia Scale (TAS-20) in clinical samples: A critical examination of the literature and a psychometric study in anorexia nervosa

There is extensive use of the 20-item Toronto Alexithymia Scale (TAS-20) in research and clinical practice in anorexia nervosa (AN), though it is not empirically established in this population. This study aims to examine the factorial validity of the TAS-20 in a Portuguese AN sample (N = 125), testing four different models (ranging from 1 to 4 factors) that were identified in critical examination of existing factor analytic studies. Results of confirmatory factor analysis (CFA) suggested that the three-factor solution, measuring difficulty identifying (DIF) and describing feelings (DDF), and externally oriented thinking (EOT), was the best fitting model. The quality of measurement improves if two EOT items (16 and 18) are eliminated. Internal consistency of EOT was low and decreased with age. The results provide support for the factorial validity of the TAS-20 in AN. Nevertheless, the measurement of EOT requires some caution and may be problematic in AN adolescents.Center for Psychology at the University of Porto, Portuguese Science Foundation (FCT UID/PSI/00050/2013) and EU FEDER through COMPETE 2020 program (POCI-01-0145-FEDER-007294info:eu-repo/semantics/acceptedVersio

Advanced glycoxidation and lipoxidation end products (AGEs and ALEs): an overview of their mechanisms of formation

Advanced lipoxidation end products (ALEs) and advanced glycation end products (AGEs) have a pathogenetic role in the development and progression of different oxidative-based diseases including diabetes, atherosclerosis, and neurological disorders. AGEs and ALEs represent a quite complex class of compounds that are formed by different mechanisms, by heterogeneous precursors and that can be formed either exogenously or endogenously. There is a wide interest in AGEs and ALEs involving different aspects of research which are essentially focused on set-up and application of analytical strategies (1) to identify, characterize, and quantify AGEs and ALEs in different pathophysiological conditions ; (2) to elucidate the molecular basis of their biological effects ; and (3) to discover compounds able to inhibit AGEs/ALEs damaging effects not only as biological tools aimed at validating AGEs/ALEs as drug target, but also as promising drugs. All the above-mentioned research stages require a clear picture of the chemical formation of AGEs/ALEs but this is not simple, due to the complex and heterogeneous pathways, involving different precursors and mechanisms. In view of this intricate scenario, the aim of the present review is to group the main AGEs and ALEs and to describe, for each of them, the precursors and mechanisms of formation