310 research outputs found
Angiosome specific revascularisation: does the evidence support it?
Objective
To explain the angiosome concept and explore the practical application of the angiosome literature to a clinical scenario, in this case a tibial angioplasty for critical ischaemia.
Methods
Clinical vignette with explanation of the decisions made and subsequent clinical results based on the theory of the angiosome concept and the literature on angiosomal revascularisation; in this case the results of our group’s recent update to a systematic review and meta-analysis.
Results
Endovascular combined or direct angiosomal revascularisation if superior to indirect revascularisation. This was borne out in the clinical scenario, where an indirect peroneal reperfusion of the AT angiosome resulted in major amputation. Open surgery is less dependent on the angiosome concept. The presence of adequate collateralisation into a foot arch seems to be the most important factor predicting success of indirect revascularisation. The evidence for both suffers from selection bias and many of the findings in the literature are wholly due to selection bias.
Conclusion
The angiosome concept is useful during both open and endovascular tibial revascularisation. However, the runoff in the foot is critical to success and may not follow the ‘classic’ angiosome model in diabetes
Infrapopliteal angioplasty using a combined angiosomal reperfusion strategy
Introduction
Infra-popliteal angioplasty continues to be widely performed with minimal evidence to guide
practice. Endovascular device selection is contentious and there is even uncertainty over
which artery to treat for optimum reperfusion. Direct reperfusion (DR) targets the artery supplying
the ischaemic tissue. Indirect reperfusion (IR) targets an artery supplying collaterals
to the ischaemic area. Our unit practice for the last eight years has been to attempt to open
all tibial arteries at the time of angioplasty. When successful, this results in both direct and
indirect; or combined reperfusion (CR). The aim was to review the outcomes of CR and
compare them with DR or IR alone.
Methods
An eight year retrospective review from a single unit of all infra-popliteal angioplasties was
undertaken. Wound healing, limb salvage, amputation-free and overall survival data as well
as re-intervention rates were captured for all patients. Subgroup analysis for diabetics was
undertaken. Kaplan Meier curves are presented for survival outcomes. All odds and hazard
ratios (HR) and p values were corrected for bias from confounders using multivariate analysis.
Results
250 procedures were performed: 22 (9%) were CR; 115 (46%) DR and 113 (45%) IR. Amputation-
free survival (HR 0.504, p = 0.039) and re-intervention and amputation-free survival
(HR 0.414, p = 0.005) were significantly improved in patients undergoing CR compared to
IR. Wound healing was similarly affected by reperfusion strategy (OR = 0.35, p = 0.047).
Effects of CR over IR were similar when only diabetic patients were considered.
Conclusions
Combined revascularisation can only be achieved in approximately 10% of patients. However,
when successful, it results in significant improvements in wound healing and amputation-
free survival over simple indirect reperfusion techniques
The architectures of translation : a magic carpet-ride through space and time (or, the awkward story of how we dis/placed Krisztina Tóth’s short fiction from Hungarian to English)
This interdisciplinary paper unfolds an account of a collaborative translation project, which draws on Ellen Eve Frank’s concept of “literary architecture” to propose a process of “architectural translation”. Our proposal is illustrated by a detailed account of our experiences translating the short fiction of contemporary Hungarian writer, Krisztina Tóth (b. 1967) into English. Staged as a journey through space, time and text, our enquiry frames the process in Barbara Godard’s terms as one of dis/placement, finding resonances with Rosi Braidotti’s nomadic subject and practices of feminist mimesis. Situating Tóth’s fiction in a European feminist literary heritage, we deploy a range of concepts drawn from translation, architecture, literary criticism and feminist philosophy to synthesise a translation strategy which engages the spatial, not only as a metaphor but a methodology for our project. In this account, we propose an architectural methodology as a tool for radical translators, and offer the process of translation as a way of thinking about internal and external spaces in postcolonial contexts
Portable X-ray fluorescence (pXRF) analysis of heavy metal contamination in church graveyards with contrasting soil types.
Human remains have been interred in burial grounds since historic times. Although the re-use of graveyards differs from one country, region or time-period to another, over time graveyard soil may become contaminated or enriched with heavy metal elements. This paper presents heavy metal element soil analysis from two UK church graveyard study sites with contrasting necrosols, but similar burial densities and known burial ages dating back to the 16th Century and some possibly older than 1,000 years. Portable X-Ray fluorescence (pXRF) element laboratory-based analyses were undertaken on surface and near-surface soil pellets. Results show elevated levels of Fe, Pb, Mn, Cr, Cu, Zn and Ca in both necrosols when compared with background values. Element concentration anomalies remained consistently higher than background samples down to 2 m , but reduced with distance away from church buildings. Element concentration anomalies are higher in the clay-rich necrosol than in sandy necrosol. Study results implications suggest that long-used necrosols are likely to be more contaminated with heavy-metal elements than similar soil outside graveyards with implications for burial grounds management, adjacent populations and where burial grounds have been deconsecrated and turned to residential dwellings
Pain in veterans of the Gulf War of 1991: a systematic review
BACKGROUND: Veterans of the Persian Gulf War of 1991 have reported a range of adverse health symptoms. This systematic review aims to identify all studies that have compared the prevalence of symptoms of pain in veterans of the Gulf War to that in a non-Gulf military comparison group, and to determine whether Gulf War veterans are at increased risk of reporting pain. METHODS: Studies published between January 1990 and May 2004 were identified by searching a large number of electronic databases. Reference lists and websites were also searched and key researchers were contacted. Studies were included if they reported the prevalence of any symptom or condition that included the word "pain" in Gulf War veterans and in a comparison group of non-Gulf veterans. 2401 abstracts were independently reviewed by two authors. RESULTS: Twenty studies fulfilled the inclusion criteria. Five main sites of pain were identified (muscle, joint, chest/heart, back and abdominal pain) and separate meta-analyses were performed to summarise the results related to each site. A greater proportion of Gulf veterans reported symptoms at each site of pain when compared to a non-Gulf military group. Gulf deployment was most strongly associated with abdominal pain, with Gulf veterans being more than three times more likely to report such pain than a comparison group (OR 3.23; 95%CI 2.31–4.51). Statistical heterogeneity between study estimates was significant, probably due to variation in measured periods of prevalence and symptom measurement methods. CONCLUSION: A higher proportion of veterans of the Persian Gulf War of 1991 reported symptoms of pain than military comparison groups. This is consistent with previously demonstrated increased reporting of more general symptoms (fatigue, multiple chemical sensitivity, post traumatic stress disorder) in these veterans compared with non-Gulf military groups. However, the primary studies were heterogeneous and varied greatly in quality
Telomere disruption results in non-random formation of de novo dicentric chromosomes involving acrocentric human chromosomes
Copyright: © 2010 Stimpson et al.Genome rearrangement often produces chromosomes with two centromeres (dicentrics) that are inherently unstable because of bridge formation and breakage during cell division. However, mammalian dicentrics, and particularly those in humans, can be quite stable, usually because one centromere is functionally silenced. Molecular mechanisms of centromere inactivation are poorly understood since there are few systems to experimentally create dicentric human chromosomes. Here, we describe a human cell culture model that enriches for de novo dicentrics. We demonstrate that transient disruption of human telomere structure non-randomly produces dicentric fusions involving acrocentric chromosomes. The induced dicentrics vary in structure near fusion breakpoints and like naturally-occurring dicentrics, exhibit various inter-centromeric distances. Many functional dicentrics persist for months after formation. Even those with distantly spaced centromeres remain functionally dicentric for 20 cell generations. Other dicentrics within the population reflect centromere inactivation. In some cases, centromere inactivation occurs by an apparently epigenetic mechanism. In other dicentrics, the size of the alpha-satellite DNA array associated with CENP-A is reduced compared to the same array before dicentric formation. Extrachromosomal fragments that contained CENP-A often appear in the same cells as dicentrics. Some of these fragments are derived from the same alpha-satellite DNA array as inactivated centromeres. Our results indicate that dicentric human chromosomes undergo alternative fates after formation. Many retain two active centromeres and are stable through multiple cell divisions. Others undergo centromere inactivation. This event occurs within a broad temporal window and can involve deletion of chromatin that marks the locus as a site for CENP-A maintenance/replenishment.This work was supported by the Tumorzentrum Heidelberg/Mannheim grant (D.10026941)and by March of Dimes Research Foundation grant #1-FY06-377 and NIH R01 GM069514
Assessing survival in widowers, and controls -A nationwide, six- to nine-year follow-up
To access full text version of this article. Please click on the hyperlink "View/open" at the bottom of this pageThe aim of this study was to assess if widowers had an increased mortality rate during the first 6 to 9 years after the death of their wife, compared initially to an age-matched control group and also compared to the general population of Iceland. The study base was comprised of all 371 men born in 1924-1969 who were widowed in Iceland in 1999-2001 and 357 controls, married men, who were matched by age and residence.The widowers and controls were followed through the years 2002-2007 using information from Statistics Iceland. Mortality rates were compared between the groups and also with the general population. The mortality rate comparisons were: study group vs. control group, on the one hand, and study group vs. general population on the other. Causes of death were also compared between widowers and their wives. A statistically significant increase in mortality in the widowers' group, compared to controls, was observed.Lifestyle-related factors could not be excluded as contributing to cause of death in these cases. Being a widower was related to an increased risk of death for at least 9 years after the death of their wife.Landspitali - National University Hospital in Reykjavik Iceland,
Rannis, the Icelandic Centre for Research (provides assistance to Icelandic science & technology, Reykjavik, Iceland),
Utfararstofa Islands (a funeral home, Reykjavik, Iceland),
Swedish Cancer Society (Cancerfonden),
Styrktarsjodur Lifsins samtaka um liknarmedferd (Palliative Care Association, Iceland),
Utfarastofa Kirkjugardanna (a funeral home, Reykjavik, Iceland
Measurement and Modeling of Particle Radiation in Coal Flames
This work aims at developing a methodology that can provide information of in-flame particle radiation in industrial-scale flames. The method is based on a combination of experimental and modeling work. The experiments have been performed in the high-temperature zone of a 77 kWth swirling lignite flame. Spectral radiation, total radiative intensity, gas temperature, and gas composition were measured, and the radiative intensity in the furnace was modeled with an axisymmetric cylindrical radiation model using Mie theory for the particle properties and a statistical narrow-band model for the gas properties. The in-flame particle radiation was measured with a Fourier transform infrared (FTIR) spectrometer connected to a water-cooled probe via fiber optics. In the cross-section of the flame investigated, the particles were found to be the dominating source of radiation. Apart from giving information about particle radiation and temperature, the methodology can also provide estimates of the amount of soot radiation and the maximum contribution from soot radiation compared to the total particle radiation. In the center position in the flame, the maximum contribution from soot radiation was estimated to be less than 40% of the particle radiation. As a validation of the methodology, the modeled total radiative intensity was compared to the total intensity measured with a narrow angle radiometer and the agreement in the results was good, supporting the validity of the used approach
Efficacy and Safety of Vamorolone in Duchenne Muscular Dystrophy: A 30-Month Nonrandomized Controlled Open-Label Extension Trial
Importance: Vamorolone is a synthetic steroidal drug with potent anti-inflammatory properties. Initial open-label, multiple ascending dose-finding studies of vamorolone among boys with Duchenne muscular dystrophy (DMD) found significant motor function improvement after 6 months treatment in higher-dose (ie, ≥2.0 mg/kg/d) groups. / Objective: To investigate outcomes after 30 months of open-label vamorolone treatment. / Design, Setting, and Participants: This nonrandomized controlled trial was conducted by the Cooperative International Neuromuscular Research Group at 11 US and non-US study sites. Participants were 46 boys ages 4.5 to 7.5 years with DMD who completed the 6-month dose-finding study. Data were analyzed from July 2020 through November 2021. / Interventions: Participants were enrolled in a 24-month, long-term extension (LTE) study with vamorolone dose escalated to 2.0 or 6.0 mg/kg/d. / Main Outcomes and Measures: Change in time-to-stand (TTSTAND) velocity from dose-finding baseline to end of LTE study was the primary outcome. Efficacy assessments included timed function tests, 6-minute walk test, and NorthStar Ambulatory Assessment (NSAA). Participants with DMD treated with glucocorticoids from the Duchenne Natural History Study (DNHS) and NorthStar United Kingdom (NSUK) Network were matched and compared with participants in the LTE study receiving higher doses of vamorolone. / Results: Among 46 boys with DMD who completed the dose-finding study, 41 boys (mean [SD] age, 5.33 [0.96] years) completed the LTE study. Among 21 participants treated with higher-dose (ie, ≥2.0 mg/kg/d) vamorolone consistently throughout the 6-month dose-finding and 24-month LTE studies with data available at 30 months, there was a decrease in mean (SD) TTSTAND velocity from baseline to 30 months (0.206 [0.070] rises/s vs 0.189 (0.124) rises/s), which was not a statistically significant change (-0.011 rises/s; CI, -0.068 to 0.046 rises/s). There were no statistically significant differences between participants receiving higher-dose vamorolone and matched participants in the historical control groups receiving glucocorticoid treatment (75 patients in DNHS and 110 patients in NSUK) over a 2-year period in NSAA total score change (0.22 units vs NSUK; 95% CI, -4.48 to 4.04]; P = .92), body mass index z score change (0.002 vs DNHS SD/mo; 95% CI, -0.006 to 0.010; P = .58), or timed function test change. Vamorolone at doses up to 6.0 mg/kg/d was well tolerated, with 5 of 46 participants discontinuing prematurely and for reasons not associated with study drug. Participants in the DNHS treated with glucocorticoids had significant growth delay in comparison with participants treated with vamorolone who had stable height percentiles (0.37 percentile/mo; 95% CI, 0.23 to 0.52 percentile/mo) over time. / Conclusions and Relevance: This study found that vamorolone treatment was not associated with a change in TTSTAND velocity from baseline to 30 months among boys with DMD aged 4 to 7 years at enrollment. Vamorolone was associated with maintenance of muscle strength and function up to 30 months, similar to standard of care glucocorticoid therapy, and improved height velocity compared with growth deceleration associated with glucocorticoid treatment, suggesting that vamorolone may be an attractive candidate for treatment of DMD. Trial Registration: ClinicalTrials.gov Identifier: NCT03038399
Proliferation of Ty3/gypsy-like retrotransposons in hybrid sunflower taxa inferred from phylogenetic data
<p>Abstract</p> <p>Background</p> <p>Long terminal repeat (LTR) retrotransposons are a class of mobile genetic element capable of autonomous transposition via an RNA intermediate. Their large size and proliferative ability make them important contributors to genome size evolution, especially in plants, where they can reach exceptionally high copy numbers and contribute substantially to variation in genome size even among closely related taxa. Using a phylogenetic approach, we characterize dynamics of proliferation events of <it>Ty3/gypsy</it>-like LTR retrotransposons that led to massive genomic expansion in three <it>Helianthus </it>(sunflower) species of ancient hybrid origin. The three hybrid species are independently derived from the same two parental species, offering a unique opportunity to explore patterns of retrotransposon proliferation in light of reticulate evolutionary events in this species group.</p> <p>Results</p> <p>We demonstrate that <it>Ty3/gypsy</it>-like retrotransposons exist as multiple well supported sublineages in both the parental and hybrid derivative species and that the same element sublineage served as the source lineage of proliferation in each hybrid species' genome. This inference is based on patterns of species-specific element numerical abundance within different phylogenetic sublineages as well as through signals of proliferation events present in the distributions of element divergence values. Employing methods to date paralogous sequences within a genome, proliferation events in the hybrid species' genomes are estimated to have occurred approximately 0.5 to 1 million years ago.</p> <p>Conclusion</p> <p>Proliferation of the same retrotransposon major sublineage in each hybrid species indicates that similar dynamics of element derepression and amplification likely occurred in each hybrid taxon during their formation. Temporal estimates of these proliferation events suggest an earlier origin for these hybrid species than previously supposed.</p
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