49 research outputs found

    The growth and phosphorus acquisition of invasive plants Rudbeckia laciniata and Solidago gigantea are enhanced by arbuscular mycorrhizal fungi

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    While a number of recent studies have revealed that arbuscular mycorrhizal fungi (AMF) can mediate invasive plant success, the influence of these symbionts on the most successful and high-impact invaders is largely unexplored. Two perennial herbs of this category of invasive plants, Rudbeckia laciniata and Solidago gigantea (Asteraceae), were thus tested in a pot experiment to determine whether AMF influence their growth, the concentration of phosphorus in biomass, and photosynthesis. The following treatments, including three common AMF species, were prepared on soils representative of two habitats that are frequently invaded by both plants, namely fallow and river valley: (1) control-soil without AMF, (2) Rhizophagus irregularis, (3) Funneliformis mosseae, and (4) Claroideoglomus claroideum. The invaders were strongly dependent on AMF for their growth. The mycorrhizal dependency of R. laciniata was 88 and 63% and of S. gigantea 90 and 82% for valley and fallow soils, respectively. The fungi also increased P concentration in their biomass. However, we found different effects of the fungal species in the stimulation of plant growth and P acquisition, with R. irregularis and C. claroideum being the most and least effective symbionts, respectively. None of AMF species had an impact on the photosynthetic performance indexes of both plants. Our findings indicate that AMF have a direct effect on the early stages of R. laciniata and S. gigantea growth. The magnitude of the response of both plant species to AMF was dependent on the fungal and soil identities. Therefore, the presence of particular AMF species in a site may determine the success of their invasion

    "You kind of want to fix it don't you?" Exploring general practice trainees' experiences of managing patients with medically unexplained symptoms

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    BackgroundMuch of a General Practitioner&rsquo;s (GP) workload consists of managing patients with medically unexplained symptoms (MUS). GP trainees are often taking responsibility for looking after people with MUS for the first time and so are well placed to reflect on this and the preparation they have had for it; their views have not been documented in detail in the literature. This study aimed to explore GP trainees&rsquo; clinical and educational experiences of managing people presenting with MUS.MethodA mixed methods approach was adopted. All trainees from four London GP vocational training schemes were invited to take part in a questionnaire and in-depth semi-structured interviews. The questionnaire explored educational and clinical experiences and attitudes towards MUS using Likert scales and free text responses. The interviews explored the origins of these views and experiences in more detail and documented ideas about optimising training about MUS. Interviews were analysed using the framework analysis approach.ResultsEighty questionnaires out of 120 (67 %) were returned and a purposive sample of 15 trainees interviewed. Results suggested most trainees struggled to manage the uncertainty inherent in MUS consultations, feeling they often over-investigated or referred for their own reassurance. They described difficulty in broaching possible psychological aspects and/or providing appropriate explanations to patients for their symptoms. They thought that more preparation was needed throughout their training. Some had more positive experiences and found such consultations rewarding, usually after several consultations and developing a relationship with the patient.ConclusionManaging MUS is a common problem for GP trainees and results in a disproportionate amount of anxiety, frustration and uncertainty. Their training needs to better reflect their clinical experience to prepare them for managing such scenarios, which should also improve patient care.<br /

    Computed tomography evaluation of patent paraumbilical vein and its aneurysm in relation to other portosystemic collateral channels in patients with liver cirrhosis and portal hypertension

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    Purpose: The aim of the study was to evaluate the relationship between the diameter and aneurysmal dilatation of the paraumbilical vein (PUV) and the presence of portosystemic collateral shunts and their relationship with age and portal vein diameter. Material and methods: The retrospective analysis, performed in the II Department of Radiology, Medical University Hospital in Warsaw, included 126 patients (77 males and 49 females) with patent umbilical vein and signs of portal hypertension due to liver cirrhosis. All patients underwent contrast enhanced abdominal CT. The average age was 54.7 ±12.98. We analysed the number and type of portosystemic collateral channels in respect of age, sex, presence of oesophageal varices, and the diameter of the paraumbilical vein and the portal vein. Results: Our results disclosed statistically significant negative correlation between patient age and diameter of paraumbilical vein, number of portosystemic collateral channels and diameter of portal vein and positive correlation between diameter of paraumbilical vein and diameter of portal vein. A statistically significant difference in diameter of portal vein and number of collateral channels was found in groups with and without oesophageal varices. No significant difference in age and portal vein diameter was found in these groups. Conclusions: Our study showed that younger patients with liver cirrhosis are characterised by wider paraumbilical veins and higher number of portosystemic collateral channels. The presence of oesophageal varices does not correlate with age, sex, diameter of paraumbilical vein, and number of collateral portosystemic channels

    Computed tomography evaluation of patent paraumbilical vein and its aneurysm in relation to other portosystemic collateral channels in patients with liver cirrhosis and portal hypertension

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    Purpose: The aim of the study was to evaluate the relationship between the diameter and aneurysmal dilatation of the paraumbilical vein (PUV) and the presence of portosystemic collateral shunts and their relationship with age and portal vein diameter. Material and methods: The retrospective analysis, performed in the II Department of Radiology, Medical University Hospital in Warsaw, included 126 patients (77 males and 49 females) with patent umbilical vein and signs of portal hypertension due to liver cirrhosis. All patients underwent contrast enhanced abdominal CT. The average age was 54.7 ±12.98. We analysed the number and type of portosystemic collateral channels in respect of age, sex, presence of oesophageal varices, and the diameter of the paraumbilical vein and the portal vein. Results: Our results disclosed statistically significant negative correlation between patient age and diameter of paraumbilical vein, number of portosystemic collateral channels and diameter of portal vein and positive correlation between diameter of paraumbilical vein and diameter of portal vein. A statistically significant difference in diameter of portal vein and number of collateral channels was found in groups with and without oesophageal varices. No significant difference in age and portal vein diameter was found in these groups. Conclusions: Our study showed that younger patients with liver cirrhosis are characterised by wider paraumbilical veins and higher number of portosystemic collateral channels. The presence of oesophageal varices does not correlate with age, sex, diameter of paraumbilical vein, and number of collateral portosystemic channels

    Root-inhabiting fungi in alien plant species in relation to invasion status and soil chemical properties

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    In order to recognize interactions between alien vascular plants and soil microorganisms and thus better understand the mechanisms of plant invasions, we examined the mycorrhizal status, arbuscular mycorrhizal fungi (AMF) colonization rate, arbuscular mycorrhiza (AM) morphology and presence of fungal root endophytes in 37 non-native species in Central Europe.We also studied the AMF diversity and chemical properties of soils from under these species. The plant and soil materials were collected in southern Poland. We found that 35 of the species formed AM and their mycorrhizal status depended on species identity. Thirty-three taxa had AM of Arum-type alone. Lycopersicon esculentum showed intermediate AM morphology and Eragrostis albensis developed both Arum and Paris. The mycelia of dark septate endophytes (DSE) were observed in 32 of the species, while sporangia of Olpidium spp. were found in the roots of 10. Thirteen common and worldwide occurring AMF species as well as three unidentified spore morphotypes were isolated from trap cultures established with the soils from under the plant species. Claroideoglomus claroideum, Funneliformis mosseae and Septoglomus constrictum were found the most frequently. The presence of root-inhabiting fungi and the intensity of their colonization were not correlated with soil chemical properties, plant invasion status, their local abundance and habitat type. No relationships were also found between the presence of AMF, DSE and Olpidium spp. These suggest that other edaphic conditions, plant and fungal species identity or the abundance of these fungi in soils might have an impact on the occurrence and intensity of fungal root colonization in the plants under study

    Do the impacts of alien invasive plants differ from expansive native ones? : an experimental study on arbuscular mycorrhizal fungi communities

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    No studies have compared so far the effects of alien invasive and expansive native (widespread, mono-dominant) plants on arbuscular mycorrhizal fungi (AMF). Four global or European most successful invaders (Impatiens glandulifera, Reynoutria japonica, Rudbeckia laciniata, Solidago gigantea) and two expansive plants native to Europe (Artemisia vulgaris, Phalaris arundinacea) were grown in pots to elucidate the magnitude and direction of changes in AMF abundance, species richness, and species composition in soils from under multispecies native vegetation. In a second stage, the effects of these changes on a native plant, Plantago lanceolata, were assessed. Plant species identity had larger impact on AMF abundance, species richness, and species composition as well as on P. lanceolata than origin of the species (alien vs. native). This could be due to the character of AMF relationships with the plants, i.e., their mycorrhizal status and dependency on AMF. However, the alterations induced by the plant species in soil chemical properties rather than in AMF community were the major drivers of differences in shoot mass and photosynthetic performance of P. lanceolata. We determined that the plants produced species-specific effects on soil properties that, in turn, resulted in species-specific soil feedbacks on the native plant. These effects were not consistent within groups of invaders or natives

    Guidance on noncorticosteroid systemic immunomodulatory therapy in noninfectious uveitis: fundamentals of care for uveitis (focus) initiative

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    Topic: An international, expert-led consensus initiative to develop systematic, evidence-based recommendations for the treatment of noninfectious uveitis in the era of biologics. Clinical Relevance: The availability of biologic agents for the treatment of human eye disease has altered practice patterns for the management of noninfectious uveitis. Current guidelines are insufficient to assure optimal use of noncorticosteroid systemic immunomodulatory agents. Methods: An international expert steering committee comprising 9 uveitis specialists (including both ophthalmologists and rheumatologists) identified clinical questions and, together with 6 bibliographic fellows trained in uveitis, conducted a Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol systematic reviewof the literature (English language studies from January 1996 through June 2016; Medline [OVID], the Central Cochrane library, EMBASE,CINAHL,SCOPUS,BIOSIS, andWeb of Science). Publications included randomized controlled trials, prospective and retrospective studies with sufficient follow-up, case series with 15 cases or more, peer-reviewed articles, and hand-searched conference abstracts from key conferences. The proposed statements were circulated among 130 international uveitis experts for review.Atotal of 44 globally representativegroupmembersmet in late 2016 to refine these guidelines using a modified Delphi technique and assigned Oxford levels of evidence. Results: In total, 10 questions were addressed resulting in 21 evidence-based guidance statements covering the following topics: when to start noncorticosteroid immunomodulatory therapy, including both biologic and nonbiologic agents; what data to collect before treatment; when to modify or withdraw treatment; how to select agents based on individual efficacy and safety profiles; and evidence in specific uveitic conditions. Shared decision-making, communication among providers and safety monitoring also were addressed as part of the recommendations. Pharmacoeconomic considerations were not addressed. Conclusions: Consensus guidelines were developed based on published literature, expert opinion, and practical experience to bridge the gap between clinical needs and medical evidence to support the treatment of patients with noninfectious uveitis with noncorticosteroid immunomodulatory agents
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