Problems and Solutions in Laboratory Testing for Hemophilia

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The measurement and normalisation of dielectric dissipation factor for diagnostics of transformer insulation

This article describes additional features of the method of Dielectric Dissipation Factor (DDF)/Tangent Delta (tgδ) measurement for a more accurate diagnosis of the condition of the transformer solid insulation. The proposed method is based on determining the DDF weight of solid insulation and oil in the measured value of DDF for the proper insulation zone of the transformer. The article proposes normalisation of DDF values according to the rated voltage of the transformer, and the analysis of the impact of design combining insulation and its condition on recalculation of DDF measurement results at a given temperature to the base temperature

Performance of factor IX extended half-life product measurements in external quality control assessment programs

Background: Patients with hemophilia B are increasingly treated with extended half-life (EHL) factor IX (FIX) concentrates. For the laboratory, introduction of these EHL concentrates presents a major challenge. To understand the variation in FIX activity levels, all available diagnostic assays need to be directly compared. Methods: The ECAT, UKNEQAS, and RCPAQAP have collaboratively performed a global survey to evaluate the quality of FIX measurements using FIX deficient plasma samples spiked with recombinant FIX (rFIX), rFIXFP, rFIXFc, and N9-GP to levels at typical FIX trough (6 IU/dL) and peak levels (60 IU/dL). Participants were asked to use their routine protocols, using one-stage assays (OSA) or chromogenic assays (CA). Results: In samples spiked with 6 IU/dL product, median (25%-75% range) FIX activity levels (OSA), were 8.0 IU/dL (7.0-9.2) for rFIX, 6.0 IU/dL (4.0-7.1) for rFIXFP, 6.6 IU/dL (5.5-8.0) for rFIXFc, and 4.9 IU/dL (3.5-8.4) for N9-GP. In samples spiked with 60 IU/dL, FIX activity levels measured (using OSA) was 63.0 IU/dL (59.9-67.0) for rFIX, 42.5 IU/dL (28.2-47.0) for rFIXFP, 50.0 IU/dL (45.0-55.0) for rFIXFc, and 34.0 IU/dL (24.8-67.5) for N9-GP. Considerable differences were observed between reagents for all samples. With CA, there was also quite some variation, but no differences between reagents. Conclusion: Large variation is observed in the measurement of FIX activity levels after administration of rFIX and EHL FIX products. For N9-GP, most silica-based assays show especially high levels. It is essential to standardize and improve reliability of measurements of these concentrates as diagnosis and treatment monitoring is based on these results

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Adding 6 months of androgen deprivation therapy to postoperative radiotherapy for prostate cancer: a comparison of short-course versus no androgen deprivation therapy in the RADICALS-HD randomised controlled trial

Background Previous evidence indicates that adjuvant, short-course androgen deprivation therapy (ADT) improves metastasis-free survival when given with primary radiotherapy for intermediate-risk and high-risk localised prostate cancer. However, the value of ADT with postoperative radiotherapy after radical prostatectomy is unclear. Methods RADICALS-HD was an international randomised controlled trial to test the efficacy of ADT used in combination with postoperative radiotherapy for prostate cancer. Key eligibility criteria were indication for radiotherapy after radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to radiotherapy alone (no ADT) or radiotherapy with 6 months of ADT (short-course ADT), using monthly subcutaneous gonadotropin-releasing hormone analogue injections, daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as distant metastasis arising from prostate cancer or death from any cause. Standard survival analysis methods were used, accounting for randomisation stratification factors. The trial had 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 80% to 86% (hazard ratio [HR] 0·67). Analyses followed the intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047. Findings Between Nov 22, 2007, and June 29, 2015, 1480 patients (median age 66 years [IQR 61–69]) were randomly assigned to receive no ADT (n=737) or short-course ADT (n=743) in addition to postoperative radiotherapy at 121 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 9·0 years (IQR 7·1–10·1), metastasis-free survival events were reported for 268 participants (142 in the no ADT group and 126 in the short-course ADT group; HR 0·886 [95% CI 0·688–1·140], p=0·35). 10-year metastasis-free survival was 79·2% (95% CI 75·4–82·5) in the no ADT group and 80·4% (76·6–83·6) in the short-course ADT group. Toxicity of grade 3 or higher was reported for 121 (17%) of 737 participants in the no ADT group and 100 (14%) of 743 in the short-course ADT group (p=0·15), with no treatment-related deaths. Interpretation Metastatic disease is uncommon following postoperative bed radiotherapy after radical prostatectomy. Adding 6 months of ADT to this radiotherapy did not improve metastasis-free survival compared with no ADT. These findings do not support the use of short-course ADT with postoperative radiotherapy in this patient population

Duration of androgen deprivation therapy with postoperative radiotherapy for prostate cancer: a comparison of long-course versus short-course androgen deprivation therapy in the RADICALS-HD randomised trial

Background Previous evidence supports androgen deprivation therapy (ADT) with primary radiotherapy as initial treatment for intermediate-risk and high-risk localised prostate cancer. However, the use and optimal duration of ADT with postoperative radiotherapy after radical prostatectomy remains uncertain. Methods RADICALS-HD was a randomised controlled trial of ADT duration within the RADICALS protocol. Here, we report on the comparison of short-course versus long-course ADT. Key eligibility criteria were indication for radiotherapy after previous radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to add 6 months of ADT (short-course ADT) or 24 months of ADT (long-course ADT) to radiotherapy, using subcutaneous gonadotrophin-releasing hormone analogue (monthly in the short-course ADT group and 3-monthly in the long-course ADT group), daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as metastasis arising from prostate cancer or death from any cause. The comparison had more than 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 75% to 81% (hazard ratio [HR] 0·72). Standard time-to-event analyses were used. Analyses followed intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov , NCT00541047 . Findings Between Jan 30, 2008, and July 7, 2015, 1523 patients (median age 65 years, IQR 60–69) were randomly assigned to receive short-course ADT (n=761) or long-course ADT (n=762) in addition to postoperative radiotherapy at 138 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 8·9 years (7·0–10·0), 313 metastasis-free survival events were reported overall (174 in the short-course ADT group and 139 in the long-course ADT group; HR 0·773 [95% CI 0·612–0·975]; p=0·029). 10-year metastasis-free survival was 71·9% (95% CI 67·6–75·7) in the short-course ADT group and 78·1% (74·2–81·5) in the long-course ADT group. Toxicity of grade 3 or higher was reported for 105 (14%) of 753 participants in the short-course ADT group and 142 (19%) of 757 participants in the long-course ADT group (p=0·025), with no treatment-related deaths. Interpretation Compared with adding 6 months of ADT, adding 24 months of ADT improved metastasis-free survival in people receiving postoperative radiotherapy. For individuals who can accept the additional duration of adverse effects, long-course ADT should be offered with postoperative radiotherapy. Funding Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society

ALPINE SHRUB TUNDRA WATER STORAGE AND RUNOFF DYNAMICS IN THE MACKENZIE MOUNTAINS, SAHTÚ TERRITORY, NT

Alpine regions receive large volumes of precipitation and are important to local and regional water balances, particularly during baseflow periods of winter cold and summer drought when the larger basin area is frozen and/or water limited. Alpine headwaters in western Canada are expected to warm and receive more precipitation during the coming decades, with implications for groundwater recharge and streamflow generation within these systems and the regional river networks to which they contribute. Throughout the North, thawing peat plateaus and other ice-rich permafrost features are resulting in an increased extent of thermokarst and wetland land cover. This transition places infrastructure and water resources at risk as the structural integrity and reliable flow paths previously maintained by the frozen soils become compromised. Alpine systems are particularly susceptible to hydrological change due to the amplification of climate warming with both latitude and elevation. The inherent spatial heterogeneity of these same systems makes attempts to quantify the impacts of climate change on current and future basin water balance even more challenging, yet few field studies of alpine hydrology have been conducted in northern Canada. Specifically, no hydrological field studies have previously occurred within alpine shrub tundra terrain overlapping the Taiga Cordilleran Ecozone and/or the Mackenzie River basin. The objective of this dissertation is to characterize the spatial and temporal variability in hydrological processes controlling the water balance of an alpine shrub tundra basin. Chapter Two presents five cover classes that are hydrologically distinct based on physiographic, surface, and subsurface characteristics. Glaciofluvial uplands are isolated from the channel network, routing all inputs to aquifer recharge. Peat plateaus have ice-rich permafrost at depth, resulting in limited storage and efficient subsurface runoff to neighbouring fens. Fen and riparian swamp iii cover classes both act as primary contributors to the channel network, although some fen areas may be isolated thermokarst features. These thermokarst features lose water via taliks recharging aquifers and/or evaporative loss from surface ponds. In the context of climate change, permafrost thaw will result in the replacement of peat plateaus with fens, such that both storage capacity and groundwater connections will expand. A conceptual model presents the basin storage compartments and expected flow paths linking the cover classes to each other and the larger area beyond the topographical extent of the study basin. Chapter Three utilizes the land cover classification established in Chapter Two to investigate temporal differences in 2019 open water season basin water balance. During the freshet, a large volume of snowmelt was received, and storage capacity was limited by shallow frost tables and bedfast ice. As a result, runoff generation was highly efficient and streamflow volumes large. The exception to this is the glaciofluvial upland, which channeled all snowmelt to aquifer recharge. As the freshet transitioned to summer, small magnitude rain events began to occur, and evapotranspiration became the primary means of basin water loss. Furthermore, groundwater exchange became more important to the basin water balance, with groundwater discharge from springs in the headwaters sustaining streamflow and channel bed infiltration becoming more prominent as bedfast ice and channel banks thawed. As the summer progressed, cumulative storage, streamflow, and evapotranspiration rates declined as groundwater discharge became the primary input and groundwater recharge the primary output. As climate change continues, a greater proportion of precipitation will be received as rain and the open water season will extend, resulting in a greater proportion of total annual basin outputs occurring via aquifer recharge, although shrubification and permafrost thaw may result in greater influence of evapotranspiration. Chapter Four assesses the basin runoff response following discrete precipitation events and utilizes stable isotope analysis to establish seasonally distinct source water contributions, evaporative influence, and subsurface flow paths during the 2019 open water season. The large volume of snowmelt received during the freshet caused peak streamflow rates, but only 8 % of total freshet discharge was isotopically designated as event water at the main basin outlet. In comparison, the maximum daily and total freshet event water fraction was reduced at the headwater subbasin outlet, where spring sources of groundwater discharge were more influential on streamflow. During the summer months, headwater subbasin streamflow was volumetrically and isotopically unresponsive to rain events and groundwater discharge continued to dominate. At the main outlet, early summer runoff response volumes and event water contributions following precipitation events were greatly reduced, in part due to the smaller magnitude of rain input volumes compared to snowmelt, but also due to the increase in fen storage capacity. By the late summer, the frost table also reached the mineral substrates at depth in the riparian swamp, extending the flow path for rain received by this cover class. As a result, late summer streamflow following rain was composed of even less event water and the hydrograph response was characterized by a lower peak and extended recession limb compared to the early summer event. This dissertation greatly enhances our understanding of the hydrological role alpine tundra plays in sustaining regional river systems via both surface streamflow and aquifer recharge. These findings provide the model structure and parameter values necessary for future hydrological modelling efforts that seek to better represent the contribution of these headwater subbasins to larger regional river systems under current and future climatic conditions

Recent increases in permafrost thaw rates and areal loss of palsas in the Western Northwest Territories, Canada

Decay of palsas can indicate permafrost status, particularly in regions where air temperatures have increased rapidly in recent decades. Using weather data, annual surveys of active-layer thickness, and analyses of high-resolution aerial imagery from the eastern Selwyn/western Mackenzie Mountains, NT, Canada, we show that permafrost temperatures have increased, active layers have deepened, and palsa areal extents have decreased considerably since the 1940s. High-altitude palsas thawed quickly from the 1940s to the 1980s, although some low-altitude palsas have recently decreased rapidly in areal extent due to peat-block calving. The linear rate of increasing active-layer thickness may not be congruent with the non-linear rate of areal loss of palsas. The rapid and episodic collapse of palsas at some sites highlights the necessity to consider hydrology, vegetation cover, landscape position, and morphology in palsa dynamics in addition to a warming climate. Copyright © 2017 John Wiley & Sons, Ltd

How to Optimize Activated Partial Thromboplastin Time (APTT) Testing: Solutions to Establishing and Verifying Normal Reference Intervals and Assessing APTT Reagents for Sensitivity to Heparin, Lupus Anticoagulant, and Clotting Factors

The activated partial thromboplastin time (APTT) assay is a very common coagulation test, used for several reasons. The test is conventionally used for assessing the contact factor (intrinsic) pathway of blood coagulation, and thus for screening deficiencies in this pathway, most typically factors VIII, IX, and XI. The APTT is also sensitive to contact factor deficiencies, including factor XII, prekallikrein, and high-molecular-weight kininogen. The APTT may also be elevated in a variety of conditions, including liver disease, vitamin K deficiency, and disseminated intravascular coagulation. The APTT can also be used for monitoring unfractionated heparin (UFH) therapy, as well as for screening lupus anticoagulant (LA) or for assessing thrombosis risk. Which of these separate uses is important to a given laboratory or clinician depends on the laboratory and the clinical context. For example, UFH sensitivity is important in hospital-based laboratories, where UFH therapy is used, but not in hospital-based laboratories where low-molecular-weight heparin (LMWH) is largely employed or where UFH may be assessed by anti-factor Xa testing, or in private/community laboratories not associated with a hospital system. High sensitivity to (low levels of) factors VIII, IX, and XI is generally preferred, as their deficiencies are clinically significant. Also preferred, but not usually achieved, is low sensitivity to factor XII and other contact factors, as these deficiencies are usually asymptomatic. Nevertheless, a good knowledge of factor sensitivity is usually needed, if only to help explain the reasons for a prolonged APTT in a given patient, or whether factor testing or other investigation is required. A good working knowledge of reagents sensitivity to LA is also advisable, especially when the reagent is used as part of a LA test panel, or else as a "general-purpose screening reagent." The current report is aimed at providing some guidance around these questions, and is intended as a kind of "how to" guide, that will enable laboratories to assess APTT reagents in regard to their sensitivity to heparin, LA, and clotting factors. The report also provides some advice on generation of normal reference ranges, as well as solutions for troubleshooting prolonged APTTs, when performing factor testing or searching for inhibitors