465 research outputs found

    Climatic and biogeographical drivers of functional diversity in the flora of the Canary Islands

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    Aim Functional traits can help us to elucidate biogeographical and ecological processes driving assemblage structure. We analysed the functional diversity of plant species of different evolutionary origins across an island archipelago, along environmental gradients and across geological age, to assess functional aspects of island biogeographical theory. Location Canary Islands, Spain. Major taxa studied Spermatophytes. Time period Present day. Methods We collected data for four traits (plant height, leaf length, flower length and fruit length) associated with resource acquisition, competitive ability, reproduction and dispersal ability of 893 endemic, non-endemic native and alien plant species (c. 43% of the Canary Island flora) from the literature. Linking these traits to species occurrences and composition across a 500 m × 500 m grid, we calculated functional diversity for endemic, non-endemic native and alien assemblages using multidimensional functional hypervolumes and related the resulting patterns to climatic (humidity) and island biogeographical (geographical isolation, topographic complexity and geological age) gradients. Results Trait space of endemic and non-endemic native species overlapped considerably, and alien species added novel trait combinations, expanding the overall functional space of the Canary Islands. We found that functional diversity of endemic plant assemblages was highest in geographically isolated and humid grid cells. Functional diversity of non-endemic native assemblages was highest in less isolated and humid grid cells. In contrast, functional diversity of alien assemblages was highest in arid ecosystems. Topographic complexity and geological age had only a subordinate effect on functional diversity across floristic groups. Main conclusions We found that endemic and non-endemic native island species possess similar traits, whereas alien species tend to expand functional space in ecosystems where they have been introduced. The spatial distribution of the functional diversity of floristic groups is very distinct across environmental gradients, indicating that species assemblages of different evolutionary origins thrive functionally in dissimilar habitats.publishedVersio

    Lee Silverman voice treatment versus NHS speech and language therapy versus control for dysarthria in people with Parkinson's disease (PD COMM): pragmatic, UK based, multicentre, three arm, parallel group, unblinded, randomised controlled trial

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    To assess the clinical effectiveness of two speech and language therapy approaches versus no speech and language therapy for dysarthria in people with Parkinson's disease. Pragmatic, UK based, multicentre, three arm, parallel group, unblinded, randomised controlled trial. The speech and language therapy interventions were delivered in outpatient or home settings between 26 September 2016 and 16 March 2020. 388 people with Parkinson's disease and dysarthria. Participants were randomly assigned to one of three groups (1:1:1): 130 to Lee Silverman voice treatment (LSVT LOUD), 129 to NHS speech and language therapy, and 129 to no speech and language therapy. LSVT LOUD consisted of four, face-to-face or remote, 50 min sessions each week delivered over four weeks. Home based practice activities were set for up to 5-10 mins daily on treatment days and 15 mins twice daily on non-treatment days. Dosage for the NHS speech and language therapy was determined by the local therapist in response to the participants' needs (estimated from prior research that NHS speech and language therapy participants would receive an average of one session per week over six to eight weeks). Local practices for NHS speech and language therapy were accepted, except for those within the LSVT LOUD protocol. Analyses were based on the intention to treat principle. The primary outcome was total score at three months of self-reported voice handicap index. People who received LSVT LOUD reported lower voice handicap index scores at three months after randomisation than those who did not receive speech and language therapy (-8.0 points (99% confidence interval -13.3 to -2.6); P<0.001). No evidence suggests a difference in voice handicap index scores between NHS speech and language therapy and no speech and language therapy (1.7 points (-3.8 to 7.1); P=0.43). Patients in the LSVT LOUD group also reported lower voice handicap index scores than did those randomised to NHS speech and language therapy (-9.6 points (-14.9 to -4.4); P<0.001). 93 adverse events (predominately vocal strain) were reported in the LSVT LOUD group, 46 in the NHS speech and language therapy group, and none in the no speech and language therapy group. No serious adverse events were recorded. LSVT LOUD was more effective at reducing the participant reported impact of voice problems than was no speech and language therapy and NHS speech and language therapy. NHS speech and language therapy showed no evidence of benefit compared with no speech and language therapy. ISRCTN registry ISRCTN12421382. [Abstract copyright: © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

    Lee Silverman Voice Treatment versus NHS Speech and Language Therapy versus control for dysarthria in Parkinson’s disease (PD COMM):a UK, multicentre, pragmatic, randomised controlled trial

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    Objectives: We aimed to assess the clinical effectiveness of two speech and language therapy (SLT) approaches versus no speech and language therapy for dysarthria in people with Parkinson’s disease. Design: This was a pragmatic, UK-wide, multicentre, three-arm, parallel group, unblinded, randomised controlled trial. Participants were randomly assigned using minimisation in a 1:1:1 ratio to Lee Silverman Voice Treatment (LSVT LOUD®), NHS SLT, or no SLT. Analyses were based on the intention to treat principle.Setting: The speech and language therapy interventions were delivered in outpatient or home settings.Participants: Between September 2016 and March 2020, 388 people with Parkinson’s disease and dysarthria were randomised into the trial: 130 to LSVT LOUD®, 129 to NHS SLT, and 129 to no SLT.Interventions: Lee Silverman Voice Treatment (LSVT LOUD®) consisted of four, face-to-face or remote, 50-minute sessions each week delivered over 4 weeks. Home-based practice activities were set for up to 5 to 10 minutes daily on treatment days and 15 minutes twice daily on non-treatment days. NHS Speech and language therapy (NHS SLT) dosage was determined by the local therapist in response to individual participants’ needs. Prior research suggested that NHS SLT participants would receive an average of one session per week over 6 to 8 weeks. Local practices for NHS SLT were accepted, except for those within the LSVT LOUD® protocol. Main outcome measures: The primary outcome was the self-reported Voice Handicap Index (VHI) total score at 3 months.Results: People randomised to LSVT LOUD® reported lower VHI scores at 3 months post-randomisation than those who were randomised to no SLT (-8·0 points (99%CI: -13·3 to -2·6); p = 0·0001). There was no evidence of a difference in VHI scores between NHS SLT and no SLT (1·7 points; (99%Cl: -3·8 to 7·1); p = 0·43). Patients randomised to LSVT LOUD® also reported lower VHI scores than those randomised to NHS SLT (-9·6 points; (99%CI: -14·9 to -4·4); p &lt; 0.0001). There were 93 adverse events (predominately vocal strain) in the LSVT LOUD® group, 46 in the NHS SLT group, and none in the no SLT group. There were no serious adverse events. Conclusions: LSVT LOUD® was more effective at reducing the participant reported impact of voice problems than no SLT and NHS SLT. NHS SLT showed no evidence of benefit compared to no SLT. Trial registration: The completed trial registration is ISRCTN12421382. Funding: NIHR HTA Programme, project number HTA 10/135/02. <br/

    Biotic factors limit the invasion of the plague pathogen ( <i>Yersinia pestis</i> ) in novel geographical settings

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    Aim: The distribution of Yersinia pestis, the pathogen that causes plague in humans, is reliant upon transmission between host species; however, the degree to which host species distributions dictate the distribution of Y. pestis, compared with limitations imposed by the environmental niche of Y. pestis per se, is debated. We test whether the present-day environmental niche of Y. pestis differs between its native range and an invaded range and whether biotic factors (host distributions) can explain observed discrepancies. Location: North America and Central Asia. Major taxa studied: Yersinia pestis. Methods: We use environmental niche models to determine whether the current climatic niche of Y. pestis differs between its native range in Asia and its invaded range in North America. We then test whether the inclusion of information on the distribution of host species improves the ability of models to capture the North American niche. We use geographical null models to guard against spurious correlations arising from spatially autocorrelated occurrence points. Results: The current climatic niche of Y. pestis differs between its native and invaded regions. The Asian niche overpredicted the distribution of Y. pestis across North America. Including biotic factors along with the native climatic niche increased niche overlap between the native and invaded models, and models containing only biotic factors performed better than the native climatic niche alone. Geographical null models confirmed that the increased niche overlap through inclusion of biotic factors did not, with a couple of exceptions, arise solely from spatially autocorrelated occurrences. Main conclusions: The current climatic niche in Central Asia differs from the current climatic niche in North America. Inclusion of biotic factors improved the fit of models to the Y. pestis distribution data in its invaded region better than climate variables alone. This highlights the importance of host species when investigating zoonotic disease introductions and suggests that climatic variables alone are insufficient to predict disease distribution in novel environments

    Rapid detection of SMARCB1 sequence variation using high resolution melting

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    Background : Rhabdoid tumors are rare cancers of early childhood arising in the kidney, central nervous system and other organs. The majority are caused by somatic inactivating mutations or deletions affecting the tumor suppressor locus SMARCB1 [OMIM 601607]. Germ-line SMARCB1 inactivation has been reported in association with rhabdoid tumor, epitheloid sarcoma and familial schwannomatosis, underscoring the importance of accurate mutation screening to ascertain recurrence and transmission risks. We describe a rapid and sensitive diagnostic screening method, using high resolution melting (HRM), for detecting sequence variations in SMARCB1. Methods : Amplicons, encompassing the nine coding exons of SMARCB1, flanking splice site sequences and the 5\u27 and 3\u27 UTR, were screened by both HRM and direct DNA sequencing to establish the reliability of HRM as a primary mutation screening tool. Reaction conditions were optimized with commercially available HRM mixes. Results : The false negative rate for detecting sequence variants by HRM in our sample series was zero. Nine amplicons out of a total of 140 (6.4%) showed variant melt profiles that were subsequently shown to be false positive. Overall nine distinct pathogenic SMARCB1 mutations were identified in a total of 19 possible rhabdoid tumors. Two tumors had two distinct mutations and two harbored SMARCB1 deletion. Other mutations were nonsense or frame-shifts. The detection sensitivity of the HRM screening method was influenced by both sequence context and specific nucleotide change and varied from 1: 4 to 1:1000 (variant to wild-type DNA). A novel method involving digital HRM, followed by re-sequencing, was used to confirm mutations in tumor specimens containing associated normal tissue. Conclusions : This is the first report describing SMARCB1 mutation screening using HRM. HRM is a rapid, sensitive and inexpensive screening technology that is likely to be widely adopted in diagnostic laboratories to facilitate whole gene mutation screening

    Lee Silverman Voice Treatment versus NHS Speech and Language Therapy versus control for dysarthria in Parkinson’s disease (PD COMM):a UK, multicentre, pragmatic, randomised controlled trial

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    Objectives: We aimed to assess the clinical effectiveness of two speech and language therapy (SLT) approaches versus no speech and language therapy for dysarthria in people with Parkinson’s disease. Design: This was a pragmatic, UK-wide, multicentre, three-arm, parallel group, unblinded, randomised controlled trial. Participants were randomly assigned using minimisation in a 1:1:1 ratio to Lee Silverman Voice Treatment (LSVT LOUD®), NHS SLT, or no SLT. Analyses were based on the intention to treat principle.Setting: The speech and language therapy interventions were delivered in outpatient or home settings.Participants: Between September 2016 and March 2020, 388 people with Parkinson’s disease and dysarthria were randomised into the trial: 130 to LSVT LOUD®, 129 to NHS SLT, and 129 to no SLT.Interventions: Lee Silverman Voice Treatment (LSVT LOUD®) consisted of four, face-to-face or remote, 50-minute sessions each week delivered over 4 weeks. Home-based practice activities were set for up to 5 to 10 minutes daily on treatment days and 15 minutes twice daily on non-treatment days. NHS Speech and language therapy (NHS SLT) dosage was determined by the local therapist in response to individual participants’ needs. Prior research suggested that NHS SLT participants would receive an average of one session per week over 6 to 8 weeks. Local practices for NHS SLT were accepted, except for those within the LSVT LOUD® protocol. Main outcome measures: The primary outcome was the self-reported Voice Handicap Index (VHI) total score at 3 months.Results: People randomised to LSVT LOUD® reported lower VHI scores at 3 months post-randomisation than those who were randomised to no SLT (-8·0 points (99%CI: -13·3 to -2·6); p = 0·0001). There was no evidence of a difference in VHI scores between NHS SLT and no SLT (1·7 points; (99%Cl: -3·8 to 7·1); p = 0·43). Patients randomised to LSVT LOUD® also reported lower VHI scores than those randomised to NHS SLT (-9·6 points; (99%CI: -14·9 to -4·4); p &lt; 0.0001). There were 93 adverse events (predominately vocal strain) in the LSVT LOUD® group, 46 in the NHS SLT group, and none in the no SLT group. There were no serious adverse events. Conclusions: LSVT LOUD® was more effective at reducing the participant reported impact of voice problems than no SLT and NHS SLT. NHS SLT showed no evidence of benefit compared to no SLT. Trial registration: The completed trial registration is ISRCTN12421382. Funding: NIHR HTA Programme, project number HTA 10/135/02. <br/

    Terbium to Quantum Dot FRET Bioconjugates for Clinical Diagnostics: Influence of Human Plasma on Optical and Assembly Properties

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    Förster resonance energy transfer (FRET) from luminescent terbium complexes (LTC) as donors to semiconductor quantum dots (QDs) as acceptors allows extraordinary large FRET efficiencies due to the long Förster distances afforded. Moreover, time-gated detection permits an efficient suppression of autofluorescent background leading to sub-picomolar detection limits even within multiplexed detection formats. These characteristics make FRET-systems with LTC and QDs excellent candidates for clinical diagnostics. So far, such proofs of principle for highly sensitive multiplexed biosensing have only been performed under optimized buffer conditions and interactions between real-life clinical media such as human serum or plasma and LTC-QD-FRET-systems have not yet been taken into account. Here we present an extensive spectroscopic analysis of absorption, excitation and emission spectra along with the luminescence decay times of both the single components as well as the assembled FRET-systems in TRIS-buffer, TRIS-buffer with 2% bovine serum albumin, and fresh human plasma. Moreover, we evaluated homogeneous LTC-QD FRET assays in QD conjugates assembled with either the well-known, specific biotin-streptavidin biological interaction or, alternatively, the metal-affinity coordination of histidine to zinc. In the case of conjugates assembled with biotin-streptavidin no significant interference with the optical and binding properties occurs whereas the histidine-zinc system appears to be affected by human plasma

    Effects of climate change on the distribution of plant species and plant functional strategies on the Canary Islands

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    Aim Oceanic islands possess unique floras with high proportions of endemic species. Island floras are expected to be severely affected by changing climatic conditions as species on islands have limited distribution ranges and small population sizes and face the constraints of insularity to track their climatic niches. We aimed to assess how ongoing climate change affects the range sizes of oceanic island plants, identifying species of particular conservation concern. Location Canary Islands, Spain. Methods We combined species occurrence data from single-island endemic, archipelago endemic and nonendemic native plant species of the Canary Islands with data on current and future climatic conditions. Bayesian Additive Regression Trees were used to assess the effect of climate change on species distributions; 71% (n = 502 species) of the native Canary Island species had models deemed good enough. To further assess how climate change affects plant functional strategies, we collected data on woodiness and succulence. Results Single-island endemic species were projected to lose a greater proportion of their climatically suitable area (x ̃ = −0.36) than archipelago endemics (x ̃ = −0.28) or nonendemic native species (x ̃ = −0.26), especially on Lanzarote and Fuerteventura, which are expected to experience less annual precipitation in the future. Moreover, herbaceous single-island endemics were projected to gain less and lose more climatically suitable area than insular woody single-island endemics. By contrast, we found that succulent single-island endemics and nonendemic natives gain more and lose less climatically suitable area. Main Conclusions While all native species are of conservation importance, we emphasise single-island endemic species not characterised by functional strategies associated with water use efficiency. Our results are particularly critical for other oceanic island floras that are not constituted by such a vast diversity of insular woody species as the Canary Islands
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