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1.
Ecol Lett ; 27(5): e14415, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38712683

RESUMEN

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.


Asunto(s)
Hojas de la Planta , Ciclo del Carbono , Carbono/metabolismo
2.
Artículo en Inglés | MEDLINE | ID: mdl-39255970

RESUMEN

This guideline was developed according to the British Society for Rheumatology Guidelines Protocol by a Guideline Development Group comprising healthcare professionals with expertise in SSc and people with lived experience, as well as patient organization representatives. It is an update of the previous 2015 SSc guideline. The recommendations were developed and agreed by the group and are underpinned by published evidence, assessed by systematic literature review and reinforced by collective expert opinion of the group. It considers all aspects of SSc including general management, treatment of organ-based complications, including cardiopulmonary, renal and gastrointestinal tract manifestations, as well as broader impact of disease. Whilst it is focused on adults with SSc we expect that the guideline will be relevant to people of all ages and expert input and review by paediatric rheumatologists and other relevant specialists considered where the guideline was, or may not be, applicable to young people with SSc and juvenile-onset disease. In addition to providing guidance on disease assessment and management the full guideline also considers service organization within the National Health Service and future approaches to audit of the guideline. The lay summary that accompanies this abstract can be found in Supplemental information 1.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39255973

RESUMEN

This guideline was developed according to the British Society for Rheumatology Guidelines Protocol by a Guideline Development Group comprising healthcare professionals with expertise in SSc and people with lived experience, as well as patient organization representatives. It is an update of the previous 2015 SSc guideline. The recommendations were developed and agreed by the group and are underpinned by published evidence, assessed by systematic literature review and reinforced by collective expert opinion of the group. It considers all aspects of SSc including general management, treatment of organ-based complications, including cardiopulmonary, renal and gastrointestinal tract manifestations, as well as broader impact of disease. Whilst it is focused on adults with SSc we expect that the guideline will be relevant to people of all ages and expert input and review by paediatric rheumatologists and other relevant specialists considered where the guideline was, or may not be, applicable to young people with SSc and juvenile-onset disease. In addition to providing guidance on disease assessment and management the full guideline also considers service organization within the National Health Service and future approaches to audit of the guideline. The lay summary that accompanies this abstract can be found in Supplemental information 1.

4.
Environ Res ; 263(Pt 2): 120106, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39396603

RESUMEN

In the midwestern United States, models predict extended summer heatwaves and increasingly frequent and prolonged drought conditions. In the Chicago region, the potential for large-scale mortality of white oak trees (Quercus alba) coupled with the ongoing decline of white oak sapling recruitment are major concerns for researchers and practitioners. In this study, we determined the sources of water used by mature white oak trees and saplings in three qualitatively different sites within a remnant oak forest in Chicago during the 2021 drought. We investigated soil moisture dynamics (volumetric water content, VWC) and water isotope composition of leaf tissues (δD, δ18O), rainwater, and groundwater. These data were linked to sapling height (proxy for biomass) and ectomycorrhizal (ECM) functional types. We predicted that: (i) mature oak trees use deeper water sources and conducted hydraulic redistribution (HR), and (ii) mature trees shared water with saplings during dry periods via long-distance ECM functional types. Soil moisture decreased progressively from June to October (spring to fall), with August and September having the lowest moisture (<20 % VWC). Following rainfall recharge, temporal patterns of soil moisture showed gravity drainage and then ongoing stair-stepwise drawdown consistent with plant evapotranspiration. Leaf δD and δ18O values in mature trees and saplings were consistent with water uptake from rainfall and subsequent enrichment via evapotranspiration. In two sites, mature trees and saplings demonstrated distinct δD: δ18O slopes, with mature trees more enriched than saplings. In the third site, mature trees and saplings δD: δ18O slopes overlapped but here, the ECM community was dominated by contact-type ECM and sapling height increased with distance from the mature oak. Our findings indicate that HR was not a component of site ecohydrology, and future climate conditions may present increasing challenges for white oak recruitment as both mature trees and saplings compete for limited rainfall-derived soil moisture.

6.
Ann Rheum Dis ; 77(9): 1251-1260, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29997112

RESUMEN

Regular physical activity (PA) is increasingly promoted for people with rheumatic and musculoskeletal diseases as well as the general population. We evaluated if the public health recommendations for PA are applicable for people with inflammatory arthritis (iA; Rheumatoid Arthritis and Spondyloarthritis) and osteoarthritis (hip/knee OA) in order to develop evidence-based recommendations for advice and guidance on PA in clinical practice. The EULAR standardised operating procedures for the development of recommendations were followed. A task force (TF) (including rheumatologists, other medical specialists and physicians, health professionals, patient-representatives, methodologists) from 16 countries met twice. In the first TF meeting, 13 research questions to support a systematic literature review (SLR) were identified and defined. In the second meeting, the SLR evidence was presented and discussed before the recommendations, research agenda and education agenda were formulated. The TF developed and agreed on four overarching principles and 10 recommendations for PA in people with iA and OA. The mean level of agreement between the TF members ranged between 9.8 and 8.8. Given the evidence for its effectiveness, feasibility and safety, PA is advocated as integral part of standard care throughout the course of these diseases. Finally, the TF agreed on related research and education agendas. Evidence and expert opinion inform these recommendations to provide guidance in the development, conduct and evaluation of PA-interventions and promotion in people with iA and OA. It is advised that these recommendations should be implemented considering individual needs and national health systems.


Asunto(s)
Artritis/rehabilitación , Terapia por Ejercicio/métodos , Ejercicio Físico , Artritis Reumatoide/rehabilitación , Medicina Basada en la Evidencia/métodos , Terapia por Ejercicio/normas , Humanos , Osteoartritis de la Cadera/rehabilitación , Osteoartritis de la Rodilla/rehabilitación , Educación del Paciente como Asunto/métodos , Salud Pública/métodos , Espondiloartritis/rehabilitación
14.
Ann Bot ; 111(3): 409-18, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23275632

RESUMEN

BACKGROUND AND AIMS: Mycorrhizal specialization has been shown to limit recruitment capacity in orchids, but an increasing number of orchids are being documented as invasive or weed-like. The reasons for this proliferation were examined by investigating mycorrhizal fungi and edaphic correlates of Microtis media, an Australian terrestrial orchid that is an aggressive ecosystem and horticultural weed. METHODS: Molecular identification of fungi cultivated from M. media pelotons, symbiotic in vitro M. media seed germination assays, ex situ fungal baiting of M. media and co-occurring orchid taxa (Caladenia arenicola, Pterostylis sanguinea and Diuris magnifica) and soil physical and chemical analyses were undertaken. KEY RESULTS: It was found that: (1) M. media associates with a broad taxonomic spectrum of mycobionts including Piriformospora indica, Sebacina vermifera, Tulasnella calospora and Ceratobasidium sp.; (2) germination efficacy of mycorrhizal isolates was greater for fungi isolated from plants in disturbed than in natural habitats; (3) a higher percentage of M. media seeds germinate than D. magnifica, P. sanguinea or C. arenicola seeds when incubated with soil from M. media roots; and (4) M. media-mycorrhizal fungal associations show an unusual breadth of habitat tolerance, especially for soil phosphorus (P) fertility. CONCLUSIONS: The findings in M. media support the idea that invasive terrestrial orchids may associate with a diversity of fungi that are widespread and common, enhance seed germination in the host plant but not co-occurring orchid species and tolerate a range of habitats. These traits may provide the weedy orchid with a competitive advantage over co-occurring orchid species. If so, invasive orchids are likely to become more broadly distributed and increasingly colonize novel habitats.


Asunto(s)
Ecosistema , Micorrizas/crecimiento & desarrollo , Orchidaceae/microbiología , Microbiología del Suelo , Adaptación Fisiológica , Australia , Basidiomycota/clasificación , Basidiomycota/crecimiento & desarrollo , Variación Genética , Germinación , Especies Introducidas , Micorrizas/clasificación , Orchidaceae/crecimiento & desarrollo , Fósforo/química , Filogenia , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Semillas/crecimiento & desarrollo , Suelo/química , Simbiosis
15.
Rheumatol Adv Pract ; 7(1): rkad022, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36923262

RESUMEN

This guideline will provide a practical roadmap for management of SSc that builds upon the previous treatment guideline to incorporate advances in evidence-based treatment and increased knowledge about assessment, classification and management. General approaches to management as well as treatment of specific complications will be covered, including lung, cardiac, renal and gastrointestinal tract disease, as well as RP, digital vasculopathy, skin manifestations, calcinosis and impact on quality of life. It will include guidance related to emerging approved therapies for interstitial lung disease and account for National Health Service England prescribing policies and national guidance relevant to SSc. The guideline will be developed using the methods and processes outlined in Creating Clinical Guidelines: Our Protocol. This development process to produce guidance, advice and recommendations for practice has National Institute for Health and Care Excellence accreditation.

17.
Ecology ; 90(3): 649-62, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19341136

RESUMEN

California coast live oak (Quercus agrifolia) forms tripartite symbiotic associations with arbuscular (AMF) and ectomycorrhizal (EMF) fungi. We selected oak individuals differing in topographic position and depth to groundwater (mesic valley vs. xeric hill sites) to investigate changes of tree mycorrhizal status in response to interannual rainfall variability. EMF root colonization, as well as hyphal abundance and viability in upper rhizosphere soil (0-30 cm), were negatively affected by severe multi-year drought, although not to the same extent in each topographic location. Oak trees growing in hill sites showed EMF colonization levels <1% in upper roots during drought. By contrast, oaks in valley sites maintained much higher EMF colonization (>19%) in upper roots during drought. EMF root colonization increased sharply at both topographic positions during the ensuing wet year (78% in valley, 49% in hill), which indicates that the mycorrhizal status of roots in upper rhizosphere soil is highly responsive to interannual rainfall variability. Across sites and years, percentage EMF colonization and soil hyphal density and viability were strongly positively correlated with soil moisture potential, but percentage AMF root colonization was not. Interestingly, changes in percentage EMF root colonization and density of viable hyphae between a wet and a dry year were proportionally much greater in xeric hill sites than in mesic valley sites. The mycorrhizal status of oak trees was particularly responsive to changes in soil moisture at the hill sites, where roots in upper rhizosphere soil shifted from almost exclusively AMF during severe drought to predominantly EMF during the ensuing wet year. By contrast, the mycorrhizal status of oaks in the valley sites was less strongly coupled to current meteorological conditions, as roots in upper soil layers remained predominantly EMF during both a dry and a wet year. Canopy shading and hydraulic lift by oaks in valley sites likely contributed to maintain the integrity and viability of EMF roots and extraradical hyphae in upper rhizosphere soil during extended drought. Our results suggest that oak woodlands in water-limited ecosystems may become increasingly reliant on the AMF symbiosis under future climate change scenarios for the U.S. southwest and other world regions.


Asunto(s)
Hongos/metabolismo , Micorrizas/crecimiento & desarrollo , Quercus/microbiología , Lluvia , Agua/metabolismo , Sequías , Hongos/crecimiento & desarrollo , Hongos/fisiología , Densidad de Población , Dinámica Poblacional , Estaciones del Año , Suelo/análisis , Simbiosis
18.
Best Pract Res Clin Rheumatol ; 33(4): 101419, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31810550

RESUMEN

As primary care clinicians are typically the first point of contact for patients with musculoskeletal problems, they are crucial to the early diagnosis and treatment of patients with an incident inflammatory arthritis, like rheumatoid arthritis. Current UK and international guidelines recognise this, recommending the prompt referral of patients with suspected persistent synovitis to secondary care. In England and Wales, this is advised to occur within 3 working days. However, recent audit data suggests this recommendation is infrequently met, with some patients waiting many months for referral. In this review article we will discuss the various challenges to achieving the early referral of patients with a new-onset inflammatory arthritis from primary to secondary care. We will also describe how these challenges could potentially be overcome, with the ultimate goal of ensuring that the right patients are referred to the right services, and at the right time.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Enfermedades Reumáticas , Sinovitis , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Humanos , Atención Primaria de Salud , Derivación y Consulta , Enfermedades Reumáticas/tratamiento farmacológico , Sinovitis/tratamiento farmacológico
19.
BMJ Open ; 8(6): e021116, 2018 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-29903794

RESUMEN

OBJECTIVES: Test a method of identifying, recruiting and collecting data from children and adolescents who consult their general practitioner about a musculoskeletal condition. DESIGN: Prospective cohort feasibility study. SETTING: 13 general practices in West Midlands of England. PARTICIPANTS: Patients aged 8-19 years who consult their general practice about a musculoskeletal condition. Patients were identified via a relevant musculoskeletal Read code entered at the point of consultation. OUTCOME MEASURES: Feasibility was assessed in terms of study processes (recruitment rates), data collection procedures (duration, response variability), resource utilisation (mail-outs) and ethical considerations (acceptability). RESULTS: From October 2016 to February 2017, an eligible musculoskeletal Read code was entered on 343 occasions, 202 patients were excluded (declined, n=153; screened not suitable, n=49) at the point of consultation. The remaining 141 patients were mailed an invitation to participate (41.1%); 46 patients responded to the invitation (response rate: 32.6%), of which 27 patients consented (consent rate: 19.1%). Participants mean age was 13.7 years (SD 2.7) and current pain intensity was 2.8 (SD 2.7). All participants completed the 6-week follow-up questionnaire. All participants found the interview questions to be acceptable and would consider participating in a similar study in the future. The majority of general practitioners/nurse practitioners, and all of the research nurses reported to be adequately informed about the study and found the study processes acceptable. CONCLUSION: The expected number of participants were identified and invited, but consent rate was low (<20%) indicating that this method is not feasible (eg, for use in a large prospective study). Recruiting children and adolescents with musculoskeletal conditions in a primary care setting currently presents a challenge for researchers. Further work is needed to identify alternative ways to conduct studies in this population in order to address the current knowledge gap in this field.


Asunto(s)
Medicina General/métodos , Dolor Musculoesquelético/epidemiología , Selección de Paciente , Adolescente , Niño , Inglaterra , Estudios de Factibilidad , Femenino , Humanos , Masculino , Estudios Prospectivos , Calidad de Vida , Derivación y Consulta , Encuestas y Cuestionarios , Adulto Joven
20.
Appl Plant Sci ; 5(8)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28924511

RESUMEN

PREMISE OF THE STUDY: Arbuscular mycorrhizal fungi (AMF) are globally important root symbioses that enhance plant growth and nutrition and influence ecosystem structure and function. To better characterize levels of AMF diversity relevant to ecosystem function, deeper sequencing depth in environmental samples is needed. In this study, Illumina barcoded primers and a bioinformatics pipeline were developed and applied to study AMF diversity and community structure in environmental samples. METHODS: Libraries of small subunit ribosomal RNA fragment amplicons were amplified from environmental DNA using a single-step PCR reaction with barcoded NS31/AML2 primers. Amplicons were sequenced on an Illumina MiSeq sequencer using version 2, 2 × 250-bp paired-end chemistry, and analyzed using QIIME and RDP Classifier. RESULTS: Sequencing captured 196 to 6416 operational taxonomic units (OTUs; depending on clustering parameters) representing nine AMF genera. Regardless of clustering parameters, ∼20 OTUs dominated AMF communities (78-87% reads) with the remaining reads distributed among other OTUs. Analyses also showed significant biogeographic differences in AMF communities and that community composition could be linked to specific edaphic factors. DISCUSSION: Barcoded NS31/AML2 primers and Illumina MiSeq sequencing provide a powerful approach to address AMF diversity and variations in fungal assemblages across host plants, ecosystems, and responses to environmental drivers including global change.

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