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Bread wheat (Triticum aestivum) is a globally dominant crop and major source of calories and proteins for the human diet. Compared with its wild ancestors, modern bread wheat shows lower genetic diversity, caused by polyploidisation, domestication and breeding bottlenecks1,2. Wild wheat relatives represent genetic reservoirs, and harbour diversity and beneficial alleles that have not been incorporated into bread wheat. Here we establish and analyse extensive genome resources for Tausch's goatgrass (Aegilops tauschii), the donor of the bread wheat D genome. Our analysis of 46 Ae. tauschii genomes enabled us to clone a disease resistance gene and perform haplotype analysis across a complex disease resistance locus, allowing us to discern alleles from paralogous gene copies. We also reveal the complex genetic composition and history of the bread wheat D genome, which involves contributions from genetically and geographically discrete Ae. tauschii subpopulations. Together, our results reveal the complex history of the bread wheat D genome and demonstrate the potential of wild relatives in crop improvement.
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Genetically encoded voltage indicators (GEVIs) enable optical recording of electrical signals in the brain, providing subthreshold sensitivity and temporal resolution not possible with calcium indicators. However, one- and two-photon voltage imaging over prolonged periods with the same GEVI has not yet been demonstrated. Here, we report engineering of ASAP family GEVIs to enhance photostability by inversion of the fluorescence-voltage relationship. Two of the resulting GEVIs, ASAP4b and ASAP4e, respond to 100-mV depolarizations with ≥180% fluorescence increases, compared with the 50% fluorescence decrease of the parental ASAP3. With standard microscopy equipment, ASAP4e enables single-trial detection of spikes in mice over the course of minutes. Unlike GEVIs previously used for one-photon voltage recordings, ASAP4b and ASAP4e also perform well under two-photon illumination. By imaging voltage and calcium simultaneously, we show that ASAP4b and ASAP4e can identify place cells and detect voltage spikes with better temporal resolution than commonly used calcium indicators. Thus, ASAP4b and ASAP4e extend the capabilities of voltage imaging to standard one- and two-photon microscopes while improving the duration of voltage recordings.
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Encéfalo , Calcio , Animales , Ratones , Iluminación , Microscopía , FotonesRESUMEN
Many disease resistance genes in wheat (Triticum aestivum L.) confer strong resistance to specific pathogen races or strains, and only a small number of genes confer multipathogen resistance. The Leaf rust resistance 67 (Lr67) gene fits into the latter category as it confers partial resistance to multiple biotrophic fungal pathogens in wheat and encodes a Sugar Transport Protein 13 (STP13) family hexose-proton symporter variant. Two mutations (G144R, V387L) in the resistant variant, Lr67res, differentiate it from the susceptible Lr67sus variant. The molecular function of the Lr67res protein is not understood, and this study aimed to broaden our knowledge on this topic. Biophysical analysis of the wheat Lr67sus and Lr67res protein variants was performed using Xenopus laevis oocytes as a heterologous expression system. Oocytes injected with Lr67sus displayed properties typically associated with proton-coupled sugar transport proteins-glucose-dependent inward currents, a Km of 110 ± 10 µM glucose, and a substrate selectivity permitting the transport of pentoses and hexoses. By contrast, Lr67res induced much larger sugar-independent inward currents in oocytes, implicating an alternative function. Since Lr67res is a mutated hexose-proton symporter, the possibility of protons underlying these currents was investigated but rejected. Instead, currents in Lr67res oocytes appeared to be dominated by anions. This conclusion was supported by electrophysiology and 36Cl- uptake studies and the similarities with oocytes expressing the known chloride channel from Torpedo marmorata, TmClC-0. This study provides insights into the function of an important disease resistance gene in wheat, which can be used to determine how this gene variant underpins disease resistance in planta.
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Resistencia a la Enfermedad , Triticum , Resistencia a la Enfermedad/genética , Triticum/metabolismo , Cloro/metabolismo , Radioisótopos/metabolismo , Proteínas de Transporte de Monosacáridos/genética , Protones , Oocitos/metabolismo , Hexosas/metabolismo , Glucosa , Azúcares , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
Partial resistance to multiple biotrophic fungal pathogens in wheat (Triticum aestivum L.) is conferred by a variant of the Lr67 gene, which encodes a hexose-proton symporter. Two mutations (G144R and V387L) differentiate the resistant and susceptible protein variants (Lr67res and Lr67sus). Lr67res lacks sugar transport capability and was associated with anion transporter-like properties when expressed in Xenopus laevis oocytes. Here, we extended this functional characterization to include yeast and in planta studies. The Lr67res allele, but not Lr67sus, induced sensitivity to ions in yeast (including NaCl, LiCl, and KI), which is consistent with our previous observations that Lr67res expression in oocytes induces novel ion fluxes. We demonstrate that another naturally occurring single amino acid variant in wheat, containing only the Lr67G144R mutation, confers rust resistance. Transgenic barley plants expressing the orthologous HvSTP13 gene carrying the G144R and V387L mutations were also more resistant to Puccinia hordei infection. NaCl treatment of pot-grown adult wheat plants with the Lr67res allele induced leaf tip necrosis and partial leaf rust resistance. An Lr67res-like function can be introduced into orthologous plant hexose transporters via single amino acid mutation, highlighting the strong possibility of generating disease resistance in other crops, especially with gene editing.
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Resistencia a la Enfermedad , Hordeum , Enfermedades de las Plantas , Proteínas de Plantas , Triticum , Triticum/genética , Triticum/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resistencia a la Enfermedad/genética , Hordeum/genética , Hordeum/microbiología , Basidiomycota/fisiología , Polimorfismo Genético , Proteínas de Transporte de Monosacáridos/genética , Proteínas de Transporte de Monosacáridos/metabolismo , Plantas Modificadas Genéticamente/genéticaRESUMEN
PURPOSE: We conducted a systematic review to describe health-related quality of life (HRQOL) in rural cancer survivors (RCS), and compare HRQOL between RCS and urban cancer survivors (UCS). METHOD: We searched Medline, Embase, CINAHL Plus, and PsycINFO for studies with HRQOL in adult cancer survivors living in rural, regional, remote, and urban areas, who had completed definitive primary cancer treatment, without evidence of residual disease. Where available, we used normative and clinically important values to ascribe meaning to HRQOL data. FINDINGS: Fifteen studies (16 papers) were included. Most were from the US (n = 8) and reported on breast cancer survivors (n = 9). Six HRQOL instruments, collecting data across 16 domains, were used. Three instruments were specific to the survivorship phase. Normative and clinical data were available for 12 studies. Compared with normative populations, RCS had clinically worse physical HRQOL (6/12 studies), better social/family (5/7), and functional (3/6) HRQOL, and there were no differences in emotional or/mental HRQOL (9/12). In six studies with rural-urban comparator groups and normative and clinically important data, RCS and UCS had clinically worse physical (3/6 and 2/6, respectively) and better social/family (3/4 and 2/4 studies, respectively) HRQOL than normative populations. Functional HRQOL was better in RCS (2/4 studies) than UCS and normative populations. In 3/6 studies, there were no clinical differences in emotional or/mental HRQOL between RCS, UCS, and normative populations. CONCLUSION: Overall, HRQOL is not clearly better or worse in RCS than UCS. Future research should include different tumor types, rural residents, and survivorship-specific HRQOL instruments.
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Supervivientes de Cáncer , Calidad de Vida , Población Rural , Población Urbana , Humanos , Supervivientes de Cáncer/psicología , Población Rural/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Neoplasias/psicología , Neoplasias/terapiaRESUMEN
PURPOSE: The use of artificial intelligence (AI) tools to aid in summarizing information in medicine and research has recently garnered a huge amount of interest. While tools such as ChatGPT produce convincing and naturally sounding output, the answers are sometimes incorrect. Some of these drawbacks, it is hoped, can be avoided by using programmes trained for a more specific scope. In this study we compared the performance of a new AI tool (the-literature.com) to the latest version OpenAI's ChatGPT (GPT-4) in summarizing topics that the authors have significantly contributed to. METHODS: The AI tools were asked to produce a literature review on 7 topics. These were selected based on the research topics that the authors were intimately familiar with and have contributed to through their own publications. The output produced by the AI tools were graded on a 1-5 Likert scale for accuracy, comprehensiveness, and relevance by two fellowship trained consultant radiologists. RESULTS: The-literature.com produced 3 excellent summaries, 3 very poor summaries not relevant to the prompt, and one summary, which was relevant but did not include all relevant papers. All of the summaries produced by GPT-4 were relevant, but fewer relevant papers were identified. The average Likert rating was for the-literature was 2.88 and 3.86 for GPT-4. There was good agreement between the ratings of both radiologists (ICC = 0.883). CONCLUSION: Summaries produced by AI in its current state require careful human validation. GPT-4 on average provides higher quality summaries. Neither tool can reliably identify all relevant publications.
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Inteligencia Artificial , Radiología , Humanos , Radiología/educación , Enfermedades Musculoesqueléticas/diagnóstico por imagen , Literatura de Revisión como AsuntoRESUMEN
BACKGROUND: Capture of cancer stage at diagnosis is important yet poorly reported by health services to population-based cancer registries. In this paper we describe current completeness of stage information for endometrial cancer available in Australian cancer registries; and develop and validate a set of rules to enable cancer registry medical coders to calculate stage using data available to them (registry-derived stage or 'RD-Stage'). METHODOLOGY: Rules for deriving RD-stage (Endometrial carcinoma) were developed using the American Joint Commission on Cancer (AJCC) TNM (tumour, nodes, metastasis) Staging System (8th Edition). An expert working group comprising cancer specialists responsible for delivering cancer care, epidemiologists and medical coders reviewed and endorsed the rules. Baseline completeness of data fields required to calculate RD-Stage, and calculation of the proportion of cases for whom an RD stage could be assigned, was assessed across each Australian jurisdiction. RD-Stage (Endometrial cancer) was calculated by Victorian Cancer Registry (VCR) medical coders and compared with clinical stage recorded by the patient's treating clinician and captured in the National Gynae-Oncology Registry (NGOR). RESULTS: The necessary data completeness level for calculating RD-Stage (Endometrial carcinoma) across various Australian jurisdictions varied from 0 to 89%. Three jurisdictions captured degree of spread of cancer, rendering RD-Stage unable to be calculated. RD-Stage (Endometrial carcinoma) could not be derived for 64/485 (13%) cases and was not captured for 44/485 (9%) cases in NGOR. At stage category level (I, II, III, IV), there was concordance between RD-Stage and NGOR captured stage in 393/410 (96%) of cases (95.8%, Kendall's coefficient = 0.95). CONCLUSION: A lack of consistency in data captured by, and data sources reporting to, population-based cancer registries meant that it was not possible to provide national endometrial carcinoma stage data at diagnosis. In a sample of Victorian cases, where surgical pathology was available, there was very good concordance between RD-Stage (Endometrial carcinoma) and clinician-recorded stage data available from NGOR. RD-Stage offers promise in capturing endometrial cancer stage at diagnosis for population epidemiological purposes when it is not provided by health services, but requires more extensive validation.
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Neoplasias Endometriales , Femenino , Humanos , Estados Unidos , Australia/epidemiología , Sistema de Registros , Estadificación de Neoplasias , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/epidemiologíaRESUMEN
The COVID-19 pandemic presents significant risks to population mental health. Despite evidence of detrimental effects for adults, there has been limited examination of the impact of COVID-19 on parents and children specifically. We aim to examine patterns of parent and child (0-18 years) mental health, parent substance use, couple conflict, parenting practices, and family functioning during COVID-19, compared to pre-pandemic data, and to identify families most at risk of poor outcomes according to pre-existing demographic and individual factors, and COVID-19 stressors. Participants were Australian mothers (81%) and fathers aged 18 years and over who were parents of a child 0-18 years (N = 2365). Parents completed an online self-report survey during 'stage three' COVID-19 restrictions in April 2020. Data were compared to pre-pandemic data from four Australian population-based cohorts. Compared to pre-pandemic estimates, during the pandemic period parents reported higher rates of parent depression, anxiety, and stress (Cohen's d = 0.26-0.81, all p < 0.001), higher parenting irritability (d = 0.17-0.46, all p < 0.001), lower family positive expressiveness (d = - 0.18, p < 0.001), and higher alcohol consumption (22% vs 12% drinking four or more days per week, p < 0.001). In multivariable analyses, we consistently found that younger parent age, increased financial deprivation, pre-existing parent and child physical and mental health conditions, COVID-19 psychological and environmental stressors, and housing dissatisfaction were associated with worse parent and child functioning and more strained family relationships. Our data suggest wide-ranging, detrimental family impacts associated with the COVID-19 pandemic; and support policy actions to assist families with financial supports, leave entitlements, and social housing.
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COVID-19 , Adulto , Femenino , Niño , Humanos , Adolescente , COVID-19/epidemiología , Pandemias , Salud Mental , Australia/epidemiología , Padres/psicología , Responsabilidad Parental/psicologíaRESUMEN
OBJECTIVES: Over time, papers or reports may come to be taken for granted as evidence for some phenomenon. Researchers cite them without critically re-examining findings in the light of subsequent work. This can give rise to misleading or erroneous results and conclusions. We explore whether this has occurred in the widely reported outbreak of SARS-CoV-2 at a rehearsal of the Skagit Valley Chorale in March 2020, where it was assumed, and subsequently asserted uncritically, that the outbreak was due to a single infected person. STUDY DESIGN: Review of original report and subsequent modelling and interpretations. METHODS: We reviewed and analysed original outbreak data in relation to published data on incubation period, subsequent modelling drawing on the data, and interpretations of transmission characteristics of this incident. RESULTS: We show it is vanishingly unlikely that this was a single point source outbreak as has been widely claimed and on which modelling has been based. CONCLUSION: An unexamined assumption has led to erroneous policy conclusions about the risks of singing, and indoor spaces more generally, and the benefits of increased levels of ventilation. Although never publicly identified, one individual bears the moral burden of knowing what health outcomes have been attributed to their actions. We call for these claims to be re-examined and for greater ethical responsibility in the assumption of a point source in outbreak investigations.
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COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Brotes de Enfermedades , Washingtón , Principios MoralesRESUMEN
Background: Impulsivity is implicated in the development and maintenance of Cocaine Use Disorder (CUD). Less work has examined impulsivity's role on interest in initiating treatment, treatment adherence, or treatment response. No pharmacotherapies are approved for CUD, so efforts to understand and bolster the effects of psychotherapy are important in guiding and refining treatment. The present study examined the impact of impulsivity on interest in treatment, treatment initiation, treatment adherence, and treatment outcomes in individuals with CUD. Methods: Following the completion of a larger study on impulsivity and CUD participants were offered 14 sessions of (12 weeks) Cognitive Behavioral Relapse Prevention (CBT-RP). Before starting treatment, participants completed seven self-report and four behavioral measures of impulsivity. Sixty-eight healthy adults (36% female) with CUD (aged 49.4 ± 7.9) expressed an interest in treatment. Results: Greater scores on several self-report measures of impulsivity, and fewer difficulties with delayed gratification were associated with increased interest in treatment in both males and females. 55 participants attended at least 1 treatment session, while 13 participants did attend a single session. Individuals who attended at least one treatment session scored lower on measures of lack of perseverance and procrastination. Still, measures of impulsivity did not reliably predict session attendance nor the frequency of cocaine-positive urine samples throughout treatment. Males attended nearly twice as many treatment sessions as females despite nonsignificant associations between impulsivity in males and the number of sessions attended. Conclusions: Greater impulsivity in individuals with CUD was associated with expressing an interest in treatment, but not treatment adherence or response.
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Trastornos Relacionados con Cocaína , Cocaína , Trastornos Relacionados con Sustancias , Adulto , Masculino , Humanos , Femenino , Trastornos Relacionados con Cocaína/psicología , Resultado del Tratamiento , Cocaína/uso terapéutico , Conducta ImpulsivaRESUMEN
An organism's gut microbiome can alter its fitness, yet we do not know how gut microbiomes change as their hosts evolve in the wild. We took advantage of a five-decade 'chronosequence' of translocated fish populations to examine associated changes in the gut microbiome. Populations of Trinidadian guppies have displayed parallel phenotypic convergence six times when moved from high predation (HP) to low predation (LP) environments. Across four drainages, we found microbiomes of fish translocated 5-6 years prior to sampling were already distinct from the microbiomes of their HP source populations. Changes in environmental conditions were most important in driving this shift, followed by phenotypic shifts in gut morphology. After 30-60 years in LP environments, microbiome composition was still distinct from native LP populations, but microbiome function was not. We found some evidence that nitrogen fixation enhanced gut nutrient absorption, but most functional shifts were not parallel across drainages. Stream-and drainage-specific signatures were present for both composition and function, despite our overall finding of consistent microbiome change across drainages. As we unravel the complexities of host-microbiome evolution in the wild, studies should consider environmental microbial colonization, host phenotypic plasticity in nature, and more realistic environmental conditions excluded from laboratory studies.
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Microbioma Gastrointestinal , Poecilia , Animales , Evolución Biológica , Conducta Predatoria , RíosRESUMEN
BACKGROUND: Over the past 15 years, there has been substantial growth in web-based psychological interventions. We summarize evidence regarding the efficacy of web-based self-directed psychological interventions on depressive, anxiety and distress symptoms in people living with a chronic health condition. METHOD: We searched Medline, PsycINFO, CINAHL, EMBASE databases and Cochrane Database from 1990 to 1 May 2019. English language papers of randomized controlled trials (usual care or waitlist control) of web-based psychological interventions with a primary or secondary aim to reduce anxiety, depression or distress in adults with a chronic health condition were eligible. Results were assessed using narrative synthases and random-effects meta-analyses. RESULTS: In total 70 eligible studies across 17 health conditions [most commonly: cancer (k = 20), chronic pain (k = 9), arthritis (k = 6) and multiple sclerosis (k = 5), diabetes (k = 4), fibromyalgia (k = 4)] were identified. Interventions were based on CBT principles in 46 (66%) studies and 42 (60%) included a facilitator. When combining all chronic health conditions, web-based interventions were more efficacious than control conditions in reducing symptoms of depression g = 0.30 (95% CI 0.22-0.39), anxiety g = 0.19 (95% CI 0.12-0.27), and distress g = 0.36 (95% CI 0.23-0.49). CONCLUSION: Evidence regarding effectiveness for specific chronic health conditions was inconsistent. While self-guided online psychological interventions may help to reduce symptoms of anxiety, depression and distress in people with chronic health conditions in general, it is unclear if these interventions are effective for specific health conditions. More high-quality evidence is needed before definite conclusions can be made.
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Terapia Cognitivo-Conductual , Intervención basada en la Internet , Adulto , Ansiedad/terapia , Terapia Cognitivo-Conductual/métodos , Depresión/terapia , Humanos , Intervención Psicosocial , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
KEY MESSAGE: Stem rust resistance genes, SrRL5271 and Sr672.1 as well as SrCPI110651, from Aegilops tauschii, the diploid D genome progenitor of wheat, are sequence variants of Sr46 differing by 1-2 nucleotides leading to non-synonymous amino acid substitutions. The Aegilops tauschii (wheat D-genome progenitor) accessions RL 5271 and CPI110672 were identified as resistant to multiple races (including the Ug99) of the wheat stem rust pathogen Puccinia graminis f. sp. tritici (Pgt). This study was conducted to identify the stem rust resistance (Sr) gene(s) in both accessions. Genetic analysis of the resistance in RL 5271 identified a single dominant allele (SrRL5271) controlling resistance, whereas resistance segregated at two loci (SR672.1 and SR672.2) for a cross of CPI110672. Bulked segregant analysis placed SrRL5271 and Sr672.1 in a region on chromosome arm 2DS that encodes Sr46. Molecular marker screening, mapping and genomic sequence analysis demonstrated SrRL5271 and Sr672.1 are alleles of Sr46. The amino acid sequence of SrRL5271 and Sr672.1 is identical but differs from Sr46 (hereafter referred to as Sr46_h1 by following the gene nomenclature in wheat) by a single amino acid (N763K) and is thus designated Sr46_h2. Screening of a panel of Ae. tauschii accessions identified an additional allelic variant that differed from Sr46_h2 by a different amino acid (A648V) and was designated Sr46_h3. By contrast, the protein encoded by the susceptible allele of Ae. tauschii accession AL8/78 differed from these resistance proteins by 54 amino acid substitutions (94% nucleotide sequence gene identity). Cloning and complementation tests of the three resistance haplotypes confirmed their resistance to Pgt race 98-1,2,3,5,6 and partial resistance to Pgt race TTRTF in bread wheat. The three Sr46 haplotypes, with no virulent races detected yet, represent a valuable source for improving stem resistance in wheat.
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Aegilops , Basidiomycota , Aegilops/genética , Aminoácidos , Mapeo Cromosómico , Cromosomas de las Plantas , Diploidia , Resistencia a la Enfermedad/genética , Genes de Plantas , Haplotipos , Enfermedades de las Plantas/genética , PucciniaRESUMEN
AIM: To determine which filtering face piece (FFP3) respirators worn throughout the COVID-19 pandemic are safe for magnetic resonance imaging (MRI). MATERIALS AND METHODS: Three clinical MRI sequences were performed to assess imaging artefacts, grid distortion, and local heating for eight commercially available FFP3 respirators. All examinations were performed at Cardiff University Brain Research Imaging Centre using a 3 T Siemens Magnetom Prisma with a 64-channel head and neck coil. Each FFP3 mask was positioned on a custom-developed three-dimensional (3D) head phantom for testing. RESULTS: Five of the eight FFP3 masks contained ferromagnetic components and were regarded as "MRI unsafe". One mask was considered "MRI conditional" and only two masks were deemed "MRI safe" for both MRI staff and patients. Temperature strips positioned at the nasal bridge of the phantom did not exhibit local heating. A maximum grid distortion of 5 mm was seen in the anterior portion of the head of the ferromagnetic FFP3 masks. CONCLUSION: This study has demonstrated the importance of assessing respiratory FFP3 masks for use in and around MRI machines. Future research involving FFP3 masks can be conducted safely by following the procedures laid out in this study.
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COVID-19 , Artefactos , COVID-19/prevención & control , Humanos , Imagen por Resonancia Magnética , Máscaras , Pandemias/prevención & controlRESUMEN
In the last 20 years, stem rust caused by the fungus Puccinia graminis f. sp. tritici (Pgt), has re-emerged as a major threat to wheat and barley production in Africa and Europe. In contrast to wheat with 60 designated stem rust (Sr) resistance genes, barley's genetic variation for stem rust resistance is very narrow with only ten resistance genes genetically identified. Of these, only one complex locus consisting of three genes is effective against TTKSK, a widely virulent Pgt race of the Ug99 tribe which emerged in Uganda in 1999 and has since spread to much of East Africa and parts of the Middle East. The objective of this study was to assess the functionality, in barley, of cloned wheat Sr genes effective against race TTKSK. Sr22, Sr33, Sr35 and Sr45 were transformed into barley cv. Golden Promise using Agrobacterium-mediated transformation. All four genes were found to confer effective stem rust resistance. The barley transgenics remained susceptible to the barley leaf rust pathogen Puccinia hordei, indicating that the resistance conferred by these wheat Sr genes was specific for Pgt. Furthermore, these transgenic plants did not display significant adverse agronomic effects in the absence of disease. Cloned Sr genes from wheat are therefore a potential source of resistance against wheat stem rust in barley.
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Basidiomycota , Resistencia a la Enfermedad/genética , Hordeum , Enfermedades de las Plantas/genética , Hordeum/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
Leaf rust, caused by Puccinia hordei, is a devastating fungal disease affecting barley (Hordeum vulgare subsp. vulgare) production globally. Despite the effectiveness of genetic resistance, the deployment of single genes often compromises durability due to the emergence of virulent P. hordei races, prompting the search for new sources of resistance. Here we report on the cloning of Rph15, a resistance gene derived from barley's wild progenitor H. vulgare subsp. spontaneum. We demonstrate using introgression mapping, mutation and complementation that the Rph15 gene from the near-isogenic line (NIL) Bowman + Rph15 (referred to as BW719) encodes a coiled-coil nucleotide-binding leucine-rich repeat (NLR) protein with an integrated Zinc finger BED (ZF-BED) domain. A predicted KASP marker was developed and validated across a collection of Australian cultivars and a series of introgression lines in the Bowman background known to carry the Rph15 resistance. Rph16 from HS-680, another wild barley derived leaf rust resistance gene, was previously mapped to the same genomic region on chromosome 2H and was assumed to be allelic with Rph15 based on genetic studies. Both sequence analysis, race specificity and the identification of a knockout mutant in the HS-680 background suggest that Rph15- and Rph16-mediated resistances are in fact the same and not allelic as previously thought. The cloning of Rph15 now permits efficient gene deployment and the production of resistance gene cassettes for sustained leaf rust control.
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Basidiomycota , Hordeum , Australia , Basidiomycota/genética , Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Hordeum/genética , Enfermedades de las Plantas/genéticaRESUMEN
AIMS: The aim of this study was to report on the occurrence of antimicrobial resistant (AMR) Escherichia coli from retail chicken meat samples in the UK, with particular focus on AmpC and extended spectrum beta-lactamase (ESBL) production and carbapenem resistance. METHODS AND RESULTS: Methods from EU protocols were used for selective isolation of AmpC-/ESBL-producing E. coli, carbapenem-resistant E. coli and for performing minimum inhibitory concentrations. Additional work not part of EU protocols included viable counts, detection by PCR of blaCTX-M , blaOXA, blaSHV and blaTEM genes in ESBL-phenotype E. coli and screening for mcr plasmid-mediated colistin resistance. From the 313/309 retail chicken meat samples tested in 2016/2018, carbapenem or mcr plasmid-mediated colistin-resistant E. coli were not detected. For 2016/2018 chicken samples, 141/42 (45·0%/13·6%), 90/23 (28·8%/7·4%), 48/16 (15·3%/5·2%) and 3/3 (1·0%/1·0%) were positive for ESBL- and/or AmpC-, ESBL- alone AmpC- alone and AmpC+ESBL-phenotype E. coli respectively. ESBL-producing E. coli were predominantly blaCTX-M-1 . All AmpC and/or ESBL-phenotype E. coli were sensitive to colistin, ertapenem, imipenem, meropenem, temocillin and tigecycline, applying epidemiological cut-off values. CONCLUSIONS: A previous study in 2013/14 showed that 65·4% of retail chicken meat samples tested in the UK were positive for ESBL-producing (mainly CTX-M) E. coli. Since then the proportion of samples positive in the UK has dropped significantly to 7·4% in 2018. SIGNIFICANCE AND IMPACT OF THE STUDY: Significant reductions in antimicrobials used in the UK poultry meat sector between 2012 and 2016 may be linked to significant reductions in AmpC/ESBL-phenotype E. coli in retail chicken between 2013/14 and 2018.
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Farmacorresistencia Bacteriana , Escherichia coli/aislamiento & purificación , Aves de Corral/microbiología , beta-Lactamasas/metabolismo , Animales , Antibacterianos/farmacología , Carbapenémicos/farmacología , Pollos , Colistina/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/veterinaria , Microbiología de Alimentos , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Plásmidos/metabolismo , Reino Unido/epidemiología , beta-Lactamasas/genéticaRESUMEN
In Ghana, like many African countries, women are financially disadvantaged compared to men, which has encouraged women to form credit associations. This paper examined the "Pagwuni" Women's Group (PWG) in the Northern region of Ghana, where over 93 percent of members are smallholder farmers. Women make regular membership and social fund contributions with records kept in a secured 'money-box', opened at an agreed time. Members receive their money according to the amount contributed while the 'social fund' is for purchasing farm inputs. This study analysed the effect of the Pagwuni Women Group (PWG) financing activities on the financial needs of the group and their households' economic welfare. The study also examined the kind of innovation that this PWG adopts that differs from the traditional Village Savings and Loans Association (VSLA). In investigating the sustainability of this 'money-box' model, data was sourced from 150 participants and the group administrators using a mixed research method. Three significant findings were uncovered. First, 93.3 percent of the respondents are peasant farmers. Second, 86.7percent indicated that this money-box arrangement is their only form of savings. Hence, since PWG is a woman-only group, it offers a good opportunity to understand the interconnections between gender and the economic welfare, enhancing the potential benefits of such group savings associations. Third, access to the social fund component of money-box helped the female participants to acquire the equipment and services needed to modernise their farming activities. Policy recommendations to link such rural money box initiatives with formal financial institutions to help channel funds to small-scale female farmers are discussed.
RESUMEN
In the last 20 years, severe wheat stem rust outbreaks have been recorded in Africa, Europe, and Central Asia. This previously well controlled disease, caused by the fungus Puccinia graminis f. sp. tritici, has reemerged as a major threat to wheat cultivation. The stem rust (Sr) resistance gene Sr22 encodes a nucleotide-binding and leucine-rich repeat receptor which confers resistance to the highly virulent African stem rust isolate Ug99. Here, we show that the Sr22 gene is conserved among grasses in the Triticeae and Poeae lineages. Triticeae species contain syntenic loci with single-copy orthologs of Sr22 on chromosome 7, except Hordeum vulgare, which has experienced major expansions and rearrangements at the locus. We also describe 14 Sr22 sequence variants obtained from both Triticum boeoticum and the domesticated form of this species, T. monococcum, which have been postulated to encode both functional and nonfunctional Sr22 alleles. The nucleotide sequence analysis of these alleles identified historical sequence exchange resulting from recombination or gene conversion, including breakpoints within codons, which expanded the coding potential at these positions by introduction of nonsynonymous substitutions. Three Sr22 alleles were transformed into wheat cultivar Fielder and two postulated resistant alleles from Schomburgk (hexaploid wheat introgressed with T. boeoticum segment carrying Sr22) and T. monococcum accession PI190945, respectively, conferred resistance to P. graminis f. sp. tritici race TTKSK, thereby unequivocally confirming Sr22 effectiveness against Ug99. The third allele from accession PI573523, previously believed to confer susceptibility, was confirmed as nonfunctional against Australian P. graminis f. sp. tritici race 98-1,2,3,5,6.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
Asunto(s)
Basidiomycota/patogenicidad , Resistencia a la Enfermedad , Enfermedades de las Plantas/genética , Poaceae/genética , Australia , Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Evolución Molecular , Variación Genética , Genómica , Enfermedades de las Plantas/microbiología , Poaceae/microbiologíaRESUMEN
Microbial communities will experience novel climates in the future. Dispersal is now recognized as a driver of microbial diversity and function, but our understanding of how dispersal influences responses to novel climates is limited. We experimentally tested how the exclusion of aerially dispersed fungi and bacteria altered the compositional and functional response of soil microbial communities to drought. We manipulated dispersal and drought by collecting aerially deposited microbes after precipitation events and subjecting soil mesocosms to either filter-sterilized rain (no dispersal) or unfiltered rain (dispersal) and to either drought (25% ambient) or ambient rainfall for 6 months. We characterized community composition by sequencing 16S and ITS rRNA regions and function using community-level physiological profiles. Treatments without dispersal had lower soil microbial biomass and metabolic diversity but higher bacterial and fungal species richness. Dispersal also altered soil community response to drought; drought had a stronger effect on bacterial (but not fungal) community composition, and induced greater functional loss, when dispersal was present. Surprisingly, neither immigrants nor drought-tolerant taxa had higher abundance in dispersal treatments. We show experimentally that natural aerial dispersal rate alters soil microbial responses to disturbance. Changes in dispersal rates should be considered when predicting microbial responses to climate change.