384 research outputs found

    A Stimulatory Role for Cytokinin in the Arbuscular Mycorrhizal Symbiosis of Pea

    Get PDF
    The arbuscular mycorrhizal (AM) symbiosis between terrestrial plants and AM fungi is regulated by plant hormones. For most of these, a role has been clearly assigned in this mutualistic interaction; however, there are still contradictory reports for cytokinin (CK). Here, pea plants, the wild type (WT) cv. Sparkle and its mutant E151 (Pssym15), were inoculated with the AM fungus Rhizophagus irregularis. E151 has previously been characterized as possessing high CK levels in non-mycorrhizal (myc-) roots and exhibiting high number of fungal structures in mycorrhizal (myc+) roots. Myc- and myc+ plants were treated 7, 9, and 11 days after inoculation (DAI) with synthetic compounds known to alter CK status. WT plants were treated with a synthetic CK [6-benzylaminopurine (BAP)] or the CK degradation inhibitor INCYDE, whereas E151 plants were treated with the CK receptor antagonist PI-55. At 13 DAI, plant CK content was analyzed by mass spectrometry. The effects of the synthetic compounds on AM colonization were assessed at 28 (WT) or 35 (E151) DAI via a modified magnified intersections method. The only noticeable difference seen between myc- and myc+ plants in terms of CK content was in the levels of nucleotides (NTs). Whereas WT plants responded to fungi by lowering their NT levels, E151 plants did not. Since NTs are thought to be converted into active CK forms, this result suggests that active CKs were synthesized more effectively in WT than in E151. In general, myc+ and myc- WT plants responded similarly to INCYDE by lowering significantly their NT levels and increasing slightly their active CK levels; these responses were less obvious in BAP-treated WT plants. In contrast, the response of E151 plants to PI-55 depended on the plant mycorrhizal status. Whereas treated myc- plants exhibited high NT and low active CK levels, treated myc+ plants displayed low levels of both NTs and active CKs. Moreover, treated WT plants were more colonized than treated E151 plants. We concluded that CKs have a stimulatory role in AM colonization because increased active CK levels were paralleled with increased AM colonization while decreased CK levels corresponded to reduced AM colonization

    Orbito-frontal cortex is necessary for temporal context memory

    Get PDF
    Lesion and neuroimaging studies suggest that orbito-frontal cortex (OFC) supports temporal aspects of episodic memory. However, it is unclear whether OFC contributes to the encoding and/or retrieval of temporal context and whether it is selective for temporal relative to nontemporal (spatial) context memory. We addressed this issue with two complimentary studies: functional magnetic resonance imaging to measure OFC activity associated with successful temporal and spatial context memory during encoding and retrieval in healthy young participants, and a neuropsychological investigation to measure changes in spatial and temporal context memory in OFC lesion patients. Imaging results revealed that OFC contributed to encoding and retrieval of associations between objects and their temporal but not their spatial contexts. Consistent with this, OFC patients exhibited impairments in temporal but not spatial source memory accuracy. These results suggest that OFC plays a critical role in the formation and subsequent retrieval of temporal context

    Variation in suspected cancer referral pathways in primary care: comparative analysis across the International Benchmarking Cancer Partnership

    Get PDF
    Background International variations in cancer outcomes persist and may be influenced by differences in the accessibility and organisation of cancer patient pathways. More evidence is needed to understand to what extent variations in the structure of primary care referral pathways for cancer investigation contribute to differences in the timeliness of diagnoses and cancer outcomes in different countries. Aim To explore the variation in primary care referral pathways for the management of suspected cancer across different countries. Design and setting Descriptive comparative analysis using mixed methods across the International Cancer Benchmarking Partnership (ICBP) countries. Method Schematics of primary care referral pathways were developed across 10 ICBP jurisdictions. The schematics were initially developed using the Aarhus statement (a resource providing greater insight and precision into early cancer diagnosis research) and were further supplemented with expert insights through consulting leading experts in primary care and cancer, existing ICBP data, a focused review of existing evidence on the management of suspected cancer, published primary care cancer guidelines, and evaluations of referral tools and initiatives in primary care. Results Referral pathway schematics for 10 ICBP jurisdictions were presented alongside a descriptive comparison of the organisation of primary care management of suspected cancer. Several key areas of variation across countries were identified: inflexibility of referral pathways, lack of a managed route for non- specific symptoms, primary care practitioner decision- making autonomy, direct access to investigations, and use of emergency routes. Conclusion Analysing the differences in referral processes can prompt further research to better understand the impact of variation on the timeliness of diagnoses and cancer outcomes. Studying these schematics in local contexts may help to identify opportunities to improve care and facilitate discussions on what may constitute best referral practice

    Variation in suspected cancer referral pathways in primary care:comparative analysis across the International Benchmarking Cancer Partnership

    Get PDF
    BACKGROUND: International variations in cancer outcomes persist and may be influenced by differences in the accessibility and organisation of cancer patient pathways. More evidence is needed to understand to what extent variations in the structure of primary care referral pathways for cancer investigation contribute to differences in the timeliness of diagnoses and cancer outcomes in different countries. AIM: To explore the variation in primary care referral pathways for the management of suspected cancer across different countries. DESIGN AND SETTING: Descriptive comparative analysis using mixed methods across the International Cancer Benchmarking Partnership (ICBP) countries. METHOD: Schematics of primary care referral pathways were developed across 10 ICBP jurisdictions. The schematics were initially developed using the Aarhus statement (a resource providing greater insight and precision into early cancer diagnosis research) and were further supplemented with expert insights through consulting leading experts in primary care and cancer, existing ICBP data, a focused review of existing evidence on the management of suspected cancer, published primary care cancer guidelines, and evaluations of referral tools and initiatives in primary care. RESULTS: Referral pathway schematics for 10 ICBP jurisdictions were presented alongside a descriptive comparison of the organisation of primary care management of suspected cancer. Several key areas of variation across countries were identified: inflexibility of referral pathways, lack of a managed route for non-specific symptoms, primary care practitioner decision-making autonomy, direct access to investigations, and use of emergency routes. CONCLUSION: Analysing the differences in referral processes can prompt further research to better understand the impact of variation on the timeliness of diagnoses and cancer outcomes. Studying these schematics in local contexts may help to identify opportunities to improve care and facilitate discussions on what may constitute best referral practice

    A Stimulatory Role for Cytokinin in the Arbuscular Mycorrhizal Symbiosis of Pea

    Get PDF
    The arbuscular mycorrhizal (AM) symbiosis between terrestrial plants and AM fungi is regulated by plant hormones. For most of these, a role has been clearly assigned in this mutualistic interaction; however, there are still contradictory reports for cytokinin (CK). Here, pea plants, the wild type (WT) cv. Sparkle and its mutant E151 (Pssym15), were inoculated with the AM fungus Rhizophagus irregularis. E151 has previously been characterized as possessing high CK levels in non-mycorrhizal (myc-) roots and exhibiting high number of fungal structures in mycorrhizal (myc+) roots. Myc- and myc+ plants were treated 7, 9, and 11 days after inoculation (DAI) with synthetic compounds known to alter CK status. WT plants were treated with a synthetic CK [6-benzylaminopurine (BAP)] or the CK degradation inhibitor INCYDE, whereas E151 plants were treated with the CK receptor antagonist PI-55. At 13 DAI, plant CK content was analyzed by mass spectrometry. The effects of the synthetic compounds on AM colonization were assessed at 28 (WT) or 35 (E151) DAI via a modified magnified intersections method. The only noticeable difference seen between myc- and myc+ plants in terms of CK content was in the levels of nucleotides (NTs). Whereas WT plants responded to fungi by lowering their NT levels, E151 plants did not. Since NTs are thought to be converted into active CK forms, this result suggests that active CKs were synthesized more effectively in WT than in E151. In general, myc+ and myc- WT plants responded similarly to INCYDE by lowering significantly their NT levels and increasing slightly their active CK levels; these responses were less obvious in BAP-treated WT plants. In contrast, the response of E151 plants to PI-55 depended on the plant mycorrhizal status. Whereas treated myc- plants exhibited high NT and low active CK levels, treated myc+ plants displayed low levels of both NTs and active CKs. Moreover, treated WT plants were more colonized than treated E151 plants. We concluded that CKs have a stimulatory role in AM colonization because increased active CK levels were paralleled with increased AM colonization while decreased CK levels corresponded to reduced AM colonization

    Global population genomics of two subspecies of Cryptosporidium hominis during 500 years of evolution

    Get PDF
    Cryptosporidiosis is a major global health problem and a primary cause of diarrhoea, particularly in young children in low- and middle-income countries (LMICs). The zoonotic Cryptosporidium parvum and anthroponotic C. hominis cause most human infections. Here, we present a comprehensive whole-genome study of C. hominis, comprising 114 isolates from 16 countries within five continents. We detect two lineages with distinct biology and demography, which diverged circa 500 years ago. We consider these lineages two subspecies and propose the names C. hominis hominis and C. hominis aquapotentis (gp60 subtype IbA10G2). In our study, C. h. hominis is almost exclusively represented by isolates from LMICs in Africa and Asia and appears to have undergone recent population contraction. In contrast, C. h. aquapotentis was found in high-income countries, mainly in Europe, North America and Oceania, and appears to be expanding. Notably, C. h. aquapotentis is associated with high rates of direct human-to-human transmission, which may explain its success in countries with well-developed environmental sanitation infrastructure. Intriguingly, we detected genomic regions of introgression following secondary contact between the subspecies. This resulted in high diversity and divergence in genomic islands of putative virulence genes (GIPVs), including muc5 (CHUDEA2_430) and a hypothetical protein (CHUDEA6_5270). This diversity is maintained by balancing selection, suggesting a coevolutionary arms race with the host. Lastly, we find that recent gene flow from C. h. aquapotentis to C. h. hominis, likely associated with increased human migration, may be driving evolution of more virulent C. hominis variants

    Concurrent Oral 1 - Rheumatoid Arthritis: Treatment [OP4-OP9]: OP4. Inhibition of Radiographic Progression and Improvements in Physical Function at 2 Years, with Increasing Clinical Efficacy Over Time, in Rheumatoid Arthritis (Ra) Patients Treated with Tocilizumab (Tcz): The Lithe Study

    Get PDF
    Background: Patients with moderate to severe RA who remained on methotrexate (MTX) despite inadequate response were treated with TCZ in a double-blind, randomized, controlled phase 3 trial. Results of a 2-year planned analysis from this study are presented. Methods: Patients were randomized to treatment with TCZ 4 mg/kg + MTX (TCZ4), TCZ 8 mg/kg + MTX (TCZ8) or placebo + MTX (CON) every 4 weeks. If patients failed to respond ( 60% of patients and the DAS28 remission (DAS28 < 2.6) rate was 48% at week 52 and continued to increase to week 104. By week 52, patients treated with TCZ8 had clinically significant improvements in SJC that were maintained through week 104. Rates per 100 PY for adverse events (AEs) were higher in TCZ8 and TCZ4 (263.6, 275.4) vs CON patients (251.4) while rates for serious AEs were comparable (11.4, 12.1, 10.9, respectively). Rates per 100 PY of AEs leading to withdrawal (7.4, 32.5, 4.8) and treatment modification (8.4, 30.7, 20.4) were higher in TCZ8 and TCZ4 vs CON patients, respectively and death rates were comparable (0.6, 0.2, 0.4). Conclusions: Treatment with TCZ + MTX inhibits radiographic progression over 2 years and improves physical function as shown by DAS28 remission, LDAS and low SJC, with a manageable safety profile. Disclosure statement: E.A., F. Hoffmann-La Roche - Employee. P.A., F. Hoffmann-La Roche - Employee. R.B.-V., F. Hoffmann-La Roche - Honoraria. R.F., Genentech - Research Funding, Honoraria. J.K., F. Hoffmann-La Roche - Research funding, Honorari

    Oral abstracts 3: RA Treatment and outcomesO13. Validation of jadas in all subtypes of juvenile idiopathic arthritis in a clinical setting

    Get PDF
    Background: Juvenile Arthritis Disease Activity Score (JADAS) is a 4 variable composite disease activity (DA) score for JIA (including active 10, 27 or 71 joint count (AJC), physician global (PGA), parent/child global (PGE) and ESR). The validity of JADAS for all ILAR subtypes in the routine clinical setting is unknown. We investigated the construct validity of JADAS in the clinical setting in all subtypes of JIA through application to a prospective inception cohort of UK children presenting with new onset inflammatory arthritis. Methods: JADAS 10, 27 and 71 were determined for all children in the Childhood Arthritis Prospective Study (CAPS) with complete data available at baseline. Correlation of JADAS 10, 27 and 71 with single DA markers was determined for all subtypes. All correlations were calculated using Spearman's rank statistic. Results: 262/1238 visits had sufficient data for calculation of JADAS (1028 (83%) AJC, 744 (60%) PGA, 843 (68%) PGE and 459 (37%) ESR). Median age at disease onset was 6.0 years (IQR 2.6-10.4) and 64% were female. Correlation between JADAS 10, 27 and 71 approached 1 for all subtypes. Median JADAS 71 was 5.3 (IQR 2.2-10.1) with a significant difference between median JADAS scores between subtypes (p < 0.01). Correlation of JADAS 71 with each single marker of DA was moderate to high in the total cohort (see Table 1). Overall, correlation with AJC, PGA and PGE was moderate to high and correlation with ESR, limited JC, parental pain and CHAQ was low to moderate in the individual subtypes. Correlation coefficients in the extended oligoarticular, rheumatoid factor negative and enthesitis related subtypes were interpreted with caution in view of low numbers. Conclusions: This study adds to the body of evidence supporting the construct validity of JADAS. JADAS correlates with other measures of DA in all ILAR subtypes in the routine clinical setting. Given the high frequency of missing ESR data, it would be useful to assess the validity of JADAS without inclusion of the ESR. Disclosure statement: All authors have declared no conflicts of interest. Table 1Spearman's correlation between JADAS 71 and single markers DA by ILAR subtype ILAR Subtype Systemic onset JIA Persistent oligo JIA Extended oligo JIA Rheumatoid factor neg JIA Rheumatoid factor pos JIA Enthesitis related JIA Psoriatic JIA Undifferentiated JIA Unknown subtype Total cohort Number of children 23 111 12 57 7 9 19 7 17 262 AJC 0.54 0.67 0.53 0.75 0.53 0.34 0.59 0.81 0.37 0.59 PGA 0.63 0.69 0.25 0.73 0.14 0.05 0.50 0.83 0.56 0.64 PGE 0.51 0.68 0.83 0.61 0.41 0.69 0.71 0.9 0.48 0.61 ESR 0.28 0.31 0.35 0.4 0.6 0.85 0.43 0.7 0.5 0.53 Limited 71 JC 0.29 0.51 0.23 0.37 0.14 -0.12 0.4 0.81 0.45 0.41 Parental pain 0.23 0.62 0.03 0.57 0.41 0.69 0.7 0.79 0.42 0.53 Childhood health assessment questionnaire 0.25 0.57 -0.07 0.36 -0.47 0.84 0.37 0.8 0.66 0.4

    A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15-1.73 GHz

    Full text link
    We conducted a search for narrowband radio signals over four observing sessions in 2020-2023 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. We pointed the telescope in the directions of 62 TESS Objects of Interest, capturing radio emissions from a total of ~11,680 stars and planetary systems in the ~9 arcminute beam of the telescope. All detections were either automatically rejected or visually inspected and confirmed to be of anthropogenic nature. In this work, we also quantified the end-to-end efficiency of radio SETI pipelines with a signal injection and recovery analysis. The UCLA SETI pipeline recovers 94.0% of the injected signals over the usable frequency range of the receiver and 98.7% of the injections when regions of dense RFI are excluded. In another pipeline that uses incoherent sums of 51 consecutive spectra, the recovery rate is ~15 times smaller at ~6%. The pipeline efficiency affects calculations of transmitter prevalence and SETI search volume. Accordingly, we developed an improved Drake Figure of Merit and a formalism to place upper limits on transmitter prevalence that take the pipeline efficiency and transmitter duty cycle into account. Based on our observations, we can state at the 95% confidence level that fewer than 6.6% of stars within 100 pc host a transmitter that is detectable in our search (EIRP > 1e13 W). For stars within 20,000 ly, the fraction of stars with detectable transmitters (EIRP > 5e16 W) is at most 3e-4. Finally, we showed that the UCLA SETI pipeline natively detects the signals detected with AI techniques by Ma et al. (2023).Comment: 22 pages, 9 figures, submitted to AJ, revise
    • …
    corecore