204 research outputs found
Should we abandon the APTT for monitoring unfractionated heparin?
INTRODUCTION: The activated partial thromboplastin time (APTT) is commonly used to monitor unfractionated heparin (UFH) but may not accurately measure the amount of heparin present. The anti-Xa assay is less susceptible to confounding factors and may be a better assay for this purpose. MATERIALS AND METHODS: The validity of the APTT for monitoring UFH was assessed by comparing with an anti-Xa assay on 3543 samples from 475 patients (infants [n=165], children 1-15years [n=60] and adults [n=250]) receiving treatment dose UFH. RESULTS: Overall concordance was poor. The highest concordance (66%; 168/254) was seen in children. Concordance (51.8%) or discordance (48.4%) was almost equal in adult patients. Among adult patients whose anti-Xa level was within 0.3-0.7IU/mL, only 38% had an APTT in the therapeutic range whilst 56% were below and 6% were above therapeutic range. Children and adult patients with anti-Xa of 0.3-0.7IU/mL but sub- therapeutic APTT had significantly higher fibrinogen levels compared to those with therapeutic or supra-therapeutic APTT. CONCLUSIONS: When the anti-Xa level was 0.3-0.7IU/mL, the majority of samples from infants demonstrated a supra-therapeutic APTT, whilst adults tended to have a sub-therapeutic APTT. This may lead to under anticoagulation in infants or over anticoagulation in adults with risk of bleeding if APTT is used to monitor UFH. These results further strengthen existing evidence of the limitation of APTT in monitoring UFH. Discordance of APTT and anti-Xa level in adults and children may be due to elevation of fibrinogen level
Genetic diversity of a flightless dung beetle appears unaffected by wildfire
The wildfires of Australiaâs Black Summer in 2019/2020 caused a massive loss of wildlife and habitats, but the effects of the fire on invertebrate species post-burn are unknown. We hypothesised that the fires would negatively affect the genetic diversity of invertebrate species by impeding movement between populations due to habitat loss. We studied the genetic diversity of a flightless dung beetle, Amphistomus primonactus Matthews 1974, to determine the impact of the wildfires on this species. We examined 90 SNPs from 193 individuals across seven localities impacted by the wildfires in north-eastern New South Wales. We used STRUCTURE to determine the overall population structure of the seven localities. We calculated four within-locality genetic diversity measures (observed heterozygosity (Ho), unbiased expected heterozygosity (uHe), Shannonâs Information (1 H), and the inbreeding coefficient (FIS). We calculated three between-locality genetic diversity measures (Fixation Index (FST), Hedrickâs GâST, and Shannonâs Mutual Information (I). We used partial Mantel tests to compare the between-locality genetic diversity measures with the mean fire intensity along each pairwise linear transect, while accounting for genetic variation due to geographic distance. We compared the within-locality genetic diversity measures to the mean fire intensity at each site. STRUCTURE showed a large degree of intermixing between localities. We found no significant effect of fire on any within-locality genetic diversity measure, or on any between-locality genetic diversity measure. We suggest that the genetic diversity of A. primonactus was not significantly affected by the Black Summer wildfires. Implications for insect conservation: Our results show that the 2019/2020 wildfires had a negligible impact on the genetic structure of A. primonactus. This offers a promising outlook for the species in its recovery from the fires
Frequency of thrombocytopenia and heparin induced thrombocytopenia in patients receiving extracorporeal membrane oxygenation compared to cardiopulmonary bypass and the limited sensitivity of pre-test probability score
Objectives:To ascertain:i)the frequency of thrombocytopeniaand heparininducedthrombocytopenia (HIT), ii)positive predictive value (PPV) of the pre-test probability score (PTPS) in identifying HIT iii)clinical outcome of HITin adult patients receiving veno-venous (VV)-extracorporeal membraneoxygenation(ECMO)or veno-arterial (VA)-ECMO, comparedto cardiopulmonary bypass (CPB). Design: A single-centre, retrospective, observational cohort study from January 2016 to April 2018Setting: Tertiary referral centre for cardiac and respiratory failure Patients:Patients who received ECMOfor>48hrs or had CPB during specified period Interventions: None.Measurements and Main Results:Clinical and laboratory data were collected retrospectively. PTPS and HIT testing results were collected prospectively. Mean age (standard deviation) of the EMCO and CPB cohorts were 45.4 (Âą15.6) and 64.9 (Âą13), p< 0.00001.Median duration of CPB was 4.6 [2-16.5]hrs compared to 170.4[70-1008] hrson ECMO.Moderateand severethrombocytopenia were more common in ECMO compared to CPB throughout (p<0.0001).Thrombocytopenia increased in CPB patients on day2 but was 4normal in 83% compared to 42.3 % ofECMOpatients at day 10. Patients on ECMO also followed a similar pattern of platelet recoveryfollowing cessation of ECMO. The incidences of HIT in ECMO and CPB were 6.4% (19/298) and 0.6% (18/2998) respectivelyp<0.0001). There was no difference in prevalence of HIT in patients on VV-ECMO (9/156, 5.7%) vs VA-ECMO (11/142, 7.7%), p=0.81. The PPV of the PTPS in identifying HIT in patients post-CPB and on ECMO were 56.25% (18/32) and 25% (15/60) respectively. Mortalitywas not different with (6/19, 31.6%) or without (89/279, 32.2%) HIT in patients on ECMO,p=0.79. Conclusions Thrombocytopenia is already common at ECMO initiation. HIT is more frequent in both VV-and VA-ECMO compared to CPB. PPV of PTPSin identifying HIT was lower inECMO patients.HIT had no effect on mortality
Turkish Accession and Defining the Boundaries of Nationalism and Supranationalism: Discourses in the European Commission
The European Union in general and the European Commission in particular are
characterised by supranational governance. The enlargement policy gives the Commission
the opportunity to export and promote supranational norms and define the boundaries of
Europe as a supranational polity through the conditionality of membership and intensive
contact with the candidate countries. This article analyses the discourses of the
Commission on Turkey and gives us insights into how well Turkey fits the supranational
model in the eyes of Commission officials. It demonstrates how the boundaries of
supranationalism are set and even challenged by the prospects of Turkeyâs accession
Recombinant ADAMTS13 reduces abnormally up-regulated von Willebrand factor in plasma from patients with severe COVID-19
Thrombosis affecting the pulmonary and systemic vasculature is common during severe COVID-19 and causes adverse outcomes. Although thrombosis likely results from inflammatory activation of vascular cells, the mediators of thrombosis remain unconfirmed. In a cross-sectional cohort of 36 severe COVID-19 patients, we show that markedly increased plasma von Willebrand factor (VWF) levels were accompanied by a partial reduction in the VWF regulatory protease ADAMTS13. In all patients we find this VWF/ADAMTS13 imbalance to be associated with persistence of ultra-high-molecular-weight (UHMW) VWF multimers that are highly thrombogenic in some disease settings. Incubation of plasma samples from patients with severe COVID-19 with recombinant ADAMTS13 (rADAMTS13) substantially reduced the abnormally high VWF activity, reduced overall multimer size and depleted UHMW VWF multimers in a time and concentration dependent manner. Our data implicate disruption of normal VWF/ADAMTS13 homeostasis in the pathogenesis of severe COVID-19 and indicate that this can be reversed ex vivo by correction of low plasma ADAMTS13 levels. These findings suggest a potential therapeutic role for rADAMTS13 in helping restore haemostatic balance in COVID-19 patients
Continental scale patterns and predictors of fern richness and phylogenetic diversity
Because ferns have a wide range of habitat preferences and are widely distributed, they are an ideal group for understanding how diversity is distributed. Here we examine fern diversity on a broad-scale using standard and corrected richness measures as well as phylogenetic indices; in addition we determine the environmental predictors of each diversity metric. Using the combined records of Australian herbaria, a dataset of over 60,000 records was obtained for 89 genera to infer richness. A molecular phylogeny of all the genera was constructed and combined with the herbarium records to obtain phylogenetic diversity patterns. A hotspot of both taxic and phylogenetic diversity occurs in the Wet Tropics of northeastern Australia. Although considerable diversity is distributed along the eastern coast, some important regions of diversity are identified only after sample-standardization of richness and through the phylogenetic metric. Of all of the metrics, annual precipitation was identified as the most explanatory variable, in part, in agreement with global and regional fern studies. However, precipitation was combined with a different variable for each different metric. For corrected richness, precipitation was combined with temperature seasonality, while correlation of phylogenetic diversity to precipitation plus radiation indicated support for the species-energy hypothesis. Significantly high and significantly low phylogenetic diversity were found in geographically separate areas. These separate areas correlated with different climatic conditions such as seasonality in precipitation. The phylogenetic metrics identified additional areas of significant diversity, some of which have not been revealed using traditional taxonomic analyses, suggesting that different ecological and evolutionary processes have operated over the continent. Our study demonstrates that it is possible and vital to incorporate evolutionary metrics when inferring biodiversity hotspots from large compilations of data
AAV5-Factor VIII Gene Transfer in Severe Hemophilia A.
BACKGROUND: Patients with hemophilia A rely on exogenous factor VIII to prevent bleeding in joints, soft tissue, and the central nervous system. Although successful gene transfer has been reported in patients with hemophilia B, the large size of the factor VIII coding region has precluded improved outcomes with gene therapy in patients with hemophilia A. METHODS: We infused a single intravenous dose of a codon-optimized adeno-associated virus serotype 5 (AAV5) vector encoding a B-domain-deleted human factor VIII (AAV5-hFVIII-SQ) in nine men with severe hemophilia A. Participants were enrolled sequentially into one of three dose cohorts (low dose [one participant], intermediate dose [one participant], and high dose [seven participants]) and were followed through 52 weeks. RESULTS: Factor VIII activity levels remained at 3 IU or less per deciliter in the recipients of the low or intermediate dose. In the high-dose cohort, the factor VIII activity level was more than 5 IU per deciliter between weeks 2 and 9 after gene transfer in all seven participants, and the level in six participants increased to a normal value (>50 IU per deciliter) that was maintained at 1 year after receipt of the dose. In the high-dose cohort, the median annualized bleeding rate among participants who had previously received prophylactic therapy decreased from 16 events before the study to 1 event after gene transfer, and factor VIII use for participant-reported bleeding ceased in all the participants in this cohort by week 22. The primary adverse event was an elevation in the serum alanine aminotransferase level to 1.5 times the upper limit of the normal range or less. Progression of preexisting chronic arthropathy in one participant was the only serious adverse event. No neutralizing antibodies to factor VIII were detected. CONCLUSIONS: The infusion of AAV5-hFVIII-SQ was associated with the sustained normalization of factor VIII activity level over a period of 1 year in six of seven participants who received a high dose, with stabilization of hemostasis and a profound reduction in factor VIII use in all seven participants. In this small study, no safety events were noted, but no safety conclusions can be drawn. (Funded by BioMarin Pharmaceutical; ClinicalTrials.gov number, NCT02576795 ; EudraCT number, 2014-003880-38 .).BioMarin Pharmaceutical
New Results from HAYSTAC's Phase II Operation with a Squeezed State Receiver
A search for dark matter axions with masses has been
performed using the HAYSTAC experiment's squeezed state receiver to achieve
sub-quantum limited noise. This report includes details of the design and
operation of the experiment previously used to search for axions in the mass
ranges and (GHz) and
GHz) as well as upgrades to facilitate an extended search at
higher masses. These upgrades include improvements to the data acquisition
routine which have reduced the effective dead time by a factor of 5, allowing
for the new region to be scanned 1.6 times faster with comparable
sensitivity. No statistically significant evidence of an axion signal is found
in the range (GHz), leading to an
aggregate upper limit exclusion at the level on the axion-photon
coupling of .Comment: 20 pages, 16 figure
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