| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Abreu, P., et al.
(författare)
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Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets
- 2000
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 13:4, s. 573-589
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Tidskriftsartikel (refereegranskat)abstract
- The fragmentation functions of quarks and gluons are measured in various three-jet topologies in Z decays from the full data set collected with the DELPHI detector at the Z resonance between 1992 and 995. The results at different values of transverse momentum-like scales are compared. A parameterization of the quark and gluon fragmentation functions at a fixed reference scale is given. The quark and gluon fragmentation functions show the predicted pattern of scaling violations. The scaling violation for quark jets as a function of a transverse momentum-like scale is in a good agreement with that observed in lower energy e+e- annihilation experiments. For gluon jets it appears to be significantly stronger. The scale dependences of the gluon and quark fragmentation functions agree with the prediction of the DGLAP evolution equations from which the colour factor ratio CA/CF is measured to be: CA/CF = 2.26 ± 0.09stat. ± 0.06sys. ± 0.12clus.,scale..
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| 3. |
- Abreu, P., et al.
(författare)
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Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP
- 2001
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 15-28
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Tidskriftsartikel (refereegranskat)abstract
- Muon pair production in the process e+e- → e+e- μ+μ- is studied using the data taken at LEP1 (√s ≃ mz) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb-1. The QED predictions have been tested over the whole Q2 range accessible at LEP1 (from several GeV2/c4 to several hundred GeV2/c4) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function Fγ 2. Azimuthal correlations are used to obtain information on additional structure functions, Fγ A and Fγ B, which originate from interference terms of the scattering amplitudes. The measured ratios Fγ A/Fγ 2 and FγB/Fγ 2 are significantly different from zero and consistent with QED predictions.
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| 4. |
- Abreu, P., et al.
(författare)
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Search for sleptons in e+e- collisions at √s = 183 to 189 GeV
- 2001
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 29-42
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Tidskriftsartikel (refereegranskat)abstract
- Data taken by the DELPHI experiment at centre-of-mass energies of 183 GeV and 189 GeV with a total integrated luminosity of 212 pb-1 have been used to search for the supersymmetric partners of the electrons, muons, and taus in the context of the Minimal Supersymmetric Standard Model (MSSM). The decay topologies searched for were the direct decay (ℓ̃ → ℓx̃), producing acoplanar lepton pairs plus missing energy, and the cascade decay (ℓ → ℓx̃0 2 → ℓγx̃0 1), producing acoplanar lepton and photon pairs plus missing energy. The observed number of events is in agreement with Standard Model predictions. The 95% CL excluded mass limits for selectrons, smuons and staus are mẽ ≤ 87 GeV/c2, mμ̃ ≤ 80 GeV/c2 and mτ̃ 75 GeV/c2, respectively, for values of μ=-200 GeV/c2 and tanβ=1.5.
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| 5. |
- Meech, K. J., et al.
(författare)
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EPOXI: Comet 103P/Hartley 2 Observations from a Worldwide Campaign
- 2011
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Ingår i: Astrophysical Journal Letters. - London : IOP. - 2041-8213 .- 2041-8205. ; 734:L1, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Earth- and space-based observations provide synergistic information for space mission encounters by providing data over longer timescales, at different wavelengths and using techniques that are impossible with an in situ flyby. We report here such observations in support of the EPOXI spacecraft flyby of comet 103P/Hartley 2. The nucleus is small and dark, and exhibited a very rapidly changing rotation period. Prior to the onset of activity, the period was ~16.4?hr. Starting in 2010 August the period changed from 16.6?hr to near 19?hr in December. With respect to dust composition, most volatiles and carbon and nitrogen isotope ratios, the comet is similar to other Jupiter-family comets. What is unusual is the dominance of CO 2 -driven activity near perihelion, which likely persists out to aphelion. Near perihelion the comet nucleus was surrounded by a large halo of water-ice grains that contributed significantly to the total water production.
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| 6. |
- Abgrall, N., et al.
(författare)
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The large enriched germanium experiment for neutrinoless double beta decay (LEGEND)
- 2017
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Ingår i: AIP Conference Proceedings. - : Author(s). - 1551-7616 .- 0094-243X. ; 1894
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Konferensbidrag (refereegranskat)abstract
- The observation of neutrinoless double-beta decay (0νββ) would show that lepton number is violated, reveal that neu-trinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment covering the inverted ordering region, with effective Majorana neutrino masses of 15 - 50 meV, will require a tonne-scale experiment with excellent energy resolution and extremely low backgrounds, at the level of ∼0.1 count /(FWHM·t·yr) in the region of the signal. The current generation 76Ge experiments GERDA and the Majorana Demonstrator, utilizing high purity Germanium detectors with an intrinsic energy resolution of 0.12%, have achieved the lowest backgrounds by over an order of magnitude in the 0νββ signal region of all 0νββ experiments. Building on this success, the LEGEND collaboration has been formed to pursue a tonne-scale 76Ge experiment. The collaboration aims to develop a phased 0νββ experimental program with discovery potential at a half-life approaching or at 1028 years, using existing resources as appropriate to expedite physics results.
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| 7. |
- Franchini, M, et al.
(författare)
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Tyr2105Cys mutation in exon 22 of FVIII gene is a risk factor for the development of inhibitors in patients with mild/moderate haemophilia A
- 2006
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 12:4, s. 448-451
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Tidskriftsartikel (refereegranskat)abstract
- We report the case of a patient with mild haemophilia A, due to a Tyr2105Cys mutation in exon 22 of the C1 domain, who developed a high-titre factor VIII inhibitor (maximum titre 1600 BU) with recurrent severe haemorrhages and fatal intracranial bleeding. Based on published data, it appears that although this mutation occurs rarely in patients with mild or moderate haemophilia A, it is frequently associated with the development of high-titre inhibitors.
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| 8. |
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| 9. |
- Smati, S., et al.
(författare)
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Integrative study of diet-induced mouse models of NAFLD identifies PPARα as a sexually dimorphic drug target
- 2022
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Ingår i: Gut. - : BMJ Publishing Group. - 0017-5749 .- 1468-3288. ; 71:4, s. 807-821
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Tidskriftsartikel (refereegranskat)abstract
- We evaluated the influence of sex on the pathophysiology of non-alcoholic fatty liver disease (NAFLD). We investigated diet-induced phenotypic responses to define sex-specific regulation between healthy liver and NAFLD to identify influential pathways in different preclinical murine models and their relevance in humans. Different models of diet-induced NAFLD (high-fat diet, choline-deficient high-fat diet, Western diet or Western diet supplemented with fructose and glucose in drinking water) were compared with a control diet in male and female mice. We performed metabolic phenotyping, including plasma biochemistry and liver histology, untargeted large-scale approaches (liver metabolome, lipidome and transcriptome), gene expression profiling and network analysis to identify sex-specific pathways in the mouse liver. The different diets induced sex-specific responses that illustrated an increased susceptibility to NAFLD in male mice. The most severe lipid accumulation and inflammation/fibrosis occurred in males receiving the high-fat diet and Western diet, respectively. Sex-biased hepatic gene signatures were identified for these different dietary challenges. The peroxisome proliferator-activated receptor α (PPARα) co-expression network was identified as sexually dimorphic, and in vivo experiments in mice demonstrated that hepatocyte PPARα determines a sex-specific response to fasting and treatment with pemafibrate, a selective PPARα agonist. Liver molecular signatures in humans also provided evidence of sexually dimorphic gene expression profiles and the sex-specific co-expression network for PPARα. These findings underscore the sex specificity of NAFLD pathophysiology in preclinical studies and identify PPARα as a pivotal, sexually dimorphic, pharmacological target. NCT02390232.
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| 10. |
- Montagner, A, et al.
(författare)
-
Erratum: Hepatic circadian clock oscillators and nuclear receptors integrate microbiome-derived signals
- 2016
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Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6, s. 23951-
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Tidskriftsartikel (refereegranskat)abstract
- Scientific Reports 6: Article number: 20127; published online: 16 February 2016; updated: 20 April 2016. The original version of this Article contained an error in the spelling of the author Maha Al-Asmakh, which was incorrectly given as Al-Asmakh Maha. This has now been corrected in the PDF and HTML versions of the Article.
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| 11. |
- Simundic, AM, et al.
(författare)
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Standardization of collection requirements for fasting samples for the working group on preanalytical phase (WG-PA) of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)
- 2014
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Ingår i: Clinica Chimica Acta. - : Elsevier. - 0009-8981 .- 1873-3492. ; 432, s. 33-37
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Tidskriftsartikel (refereegranskat)abstract
- Standardized protocols for patient preparation for laboratory testing are currently lacking. Moreover, a great heterogeneity exists in the definitions of "fasting" currently being used among healthcare workers and in the literature. Marked metabolic and hormonal changes occur after food ingestion, mainly due to the absorption of fluids, lipids, proteins, carbohydrates and other food constituents. This postprandial response varies markedly in response to numerous factors, such as eating behavior, food composition, fasting duration, time of the day, chronic and acute smoking, coffee and alcohol consumption. It is therefore crucial to minimize the total variability by controlling as many of these modifying factors as possible. Control of the abovementioned effects on postprandial response can only be achieved by standardizing the way patients are prepared for laboratory testing, i.e. by defining the fasting duration, as well as what is and what is not allowed (e.g., coffee, tea, smoking, water) during the period of fasting prior to sample collection. The aim of this article is to describe the range of effects of different approaches to fasting on laboratory tests, and to provide a framework for the harmonization of definitions for fasting requirements for laboratory tests.(C) 2013 Elsevier B.V. All rights reserved.
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| 12. |
- Williams, JC, et al.
(författare)
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Urine and stone analysis for the investigation of the renal stone former: a consensus conference
- 2021
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Ingår i: Urolithiasis. - : Springer Science and Business Media LLC. - 2194-7236 .- 2194-7228. ; 49:1, s. 1-16
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Tidskriftsartikel (refereegranskat)abstract
- The Consensus Group deliberated on a number of questions concerning urine and stone analysis over a period of months, and then met to develop consensus. The Group concluded that analyses of urine and stones should be routine in the diagnosis and treatment of urinary stone diseases. At present, the 24-h urine is the most useful type of urine collection, and accepted methods for analysis are described. Patient education is also important for obtaining a proper urine sample. Graphical methods for reporting urine analysis results can be helpful both for the physician and for educating the patient as to proper dietary changes that could be beneficial. Proper analysis of stones is also essential for diagnosis and management of patients. The Consensus Group also agreed that research has shown that evaluation of urinary crystals could be very valuable, but the Group also recognizes that existing methods for assessment of crystalluria do not allow this to be part of stone treatment in many places.
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| 13. |
- Andreani, Pietro, et al.
(författare)
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Multihit multichannel time-to-digital converter with ±1% differential nonlinearity and near optimal time resolution
- 1998
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Ingår i: IEEE Journal of Solid-State Circuits. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9200. ; 33:4, s. 650-656
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Tidskriftsartikel (refereegranskat)abstract
- An eight-channel, 1 ns bin-size, 23 b dynamic range, single-chip, multihit, time-to-digital converter (TDC) is presented in this paper. A new architecture mixing two previous TDC realizations has been adopted. The chip can execute common-start or common-stop operations on the trailing, leading, or both transitions of the input channels; it stores at least 32 events/channel with a double-hit resolution of 16 ns. A prototype of about 120 mm2 has been integrated into a double-metal, single-poly, n-well 1 μm CMOS process, and its performance has been compared to that of similar devices. Test results show that a differential nonlinearity error of ±1%, an integral nonlinearity less than 0.2 least significant hit (LSB), and a time resolution of 0.443 LSB-significantly better than those of comparable TDCs and very close to the theoretical limit of 0.408 LSB-have been achieved
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| 14. |
- Erusalimsky, JD, et al.
(författare)
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In Search of 'Omics'-Based Biomarkers to Predict Risk of Frailty and Its Consequences in Older Individuals: The FRAILOMIC Initiative
- 2016
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Ingår i: Gerontology. - : S. Karger AG. - 1423-0003 .- 0304-324X. ; 62:2, s. 182-190
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Tidskriftsartikel (refereegranskat)abstract
- An increase in the number of older people experiencing disability and dependence is a critical aspect of the demographic change that will emerge within Europe due to the rise in life expectancy. In this scenario, prevention of these conditions is crucial for the well-being of older citizens and for the sustainability of our healthcare systems. Thus, the diagnosis and management of conditions like frailty, which identifies the people at the highest risk for developing those adverse outcomes, is of critical relevance. Currently, assessment of frailty relies primarily on measuring functional parameters, which have limited clinical utility. In this viewpoint article, we describe the FRAILOMIC Initiative, an international, large-scale, multi-endpoint, community- and clinic-based research study funded by the European Commission. The aim of the study is to develop validated measures, comprising both classic and ‘omics-based' laboratory biomarkers, which can predict the risk of frailty, improve the accuracy of its diagnosis in clinical practice and provide a prognostic forecast on the evolution from frailty to disability. The initiative includes eight established cohorts of older adults, encompassing >75,000 subjects, most of whom (∼70%) are aged >65 years. Data on function, nutritional status and exercise habits have been collected, and cardiovascular health has been evaluated at baseline. Subjects will be stratified as ‘non-frail' or ‘frail' using Fried's definition, all adverse outcomes of interest will be recorded and differentially expressed biomarkers associated with the risk of frailty will be identified. Genomic, proteomic and transcriptomic investigations will be carried out using array-based systems. As circulating microRNAs in plasma have been identified in the context of senescence, ageing and age-associated diseases, a miRNome-wide analysis will also be undertaken to identify a miRNA-based signature of frailty. Blood concentrations of secreted proteins known to be upregulated significantly in senescent endothelial cells and other hypothesis-driven biomarkers will be measured using ELISAs. The FRAILOMIC Initiative aims to issue a series of interim scientific reports as key results emerge. Ultimately, it is hoped that this study will contribute to the development of new clinical tools, which may help individuals to enjoy an old age that is healthier and free from disability.
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| 15. |
- Fava, Cristiano, et al.
(författare)
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Subjects heterozygous for genetic loss of function of the thiazide-sensitive cotransporter have reduced blood pressure
- 2008
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 17:3, s. 413-418
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Tidskriftsartikel (refereegranskat)abstract
- Gitelmans syndrome (GS) is an inherited recessive disorder caused by homozygous or compound heterozygous loss of function mutations of the NaCl cotransporter (NCCT) gene encoding the kidney-expressed NCCT, the pharmacological target of thiazide diuretics. An observational study estimated the prevalence of GS to 19/1 000 000, in Sweden, suggesting that similar to 1% of the population carries one mutant NCCT allele. As the phenotype of GS patients, who always carry two mutant alleles, is indistinguishable from that seen in patients treated with high-dose thiazide diuretics, we aimed at investigating whether subjects carrying one mutated NCCT allele have a phenotype resembling that of treatment with low-dose thiazide diuretics. We screened first-degree relatives of 18 of our patients with an established clinical end genetic diagnosis of GS for NCCT loss of function mutations and identified 35 healthy subjects carrying one mutant allele (GS-heterozygotes). Each GS-heterozygote was assigned a healthy control subject matched for age, BMI and sex. GS-heterozygotes had markedly lower blood pressure (systolic 103.3 +/- 16.4 versus 123.2 +/- 19.4 mmHg; diastolic 62.5 +/- 10.5 versus 73.1 +/- 9.4 mmHg; P < 0.001) than controls. There was no significant difference between the groups either in plasma concentration or urinary excretion rate of electrolytes, however, GS-heterozygotes had higher fasting plasma glucose concentration. Similar to patients being treated with low-dose thiazide diuretics, GS-heterozygotes have markedly lower blood pressure and slightly higher fasting plasma glucose compared with control subjects. Our findings suggest that GS-heterozygotes, the prevalence of which can be estimated to 1%, are partially protected from hypertension through partial genetic loss of function of the NCCT. However, as our study had a case-control design, it is important to underline that any potential effects on population blood pressure and risk of future cardiovascular disease need to be examined in prospective and population-based studies.
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| 16. |
- Jones, Geraint H., et al.
(författare)
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The Comet Interceptor Mission
- 2024
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Ingår i: Space Science Reviews. - : Springer Nature. - 0038-6308 .- 1572-9672. ; 220:1
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Tidskriftsartikel (refereegranskat)abstract
- Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA’s F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum Δ V capability of 600 ms − 1 . Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes – B1, provided by the Japanese space agency, JAXA, and B2 – that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission’s science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.
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| 17. |
- Montagner, A, et al.
(författare)
-
Hepatic circadian clock oscillators and nuclear receptors integrate microbiome-derived signals
- 2016
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Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6, s. 20127-
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Tidskriftsartikel (refereegranskat)abstract
- The liver is a key organ of metabolic homeostasis with functions that oscillate in response to food intake. Although liver and gut microbiome crosstalk has been reported, microbiome-mediated effects on peripheral circadian clocks and their output genes are less well known. Here, we report that germ-free (GF) mice display altered daily oscillation of clock gene expression with a concomitant change in the expression of clock output regulators. Mice exposed to microbes typically exhibit characterized activities of nuclear receptors, some of which (PPARα, LXRβ) regulate specific liver gene expression networks, but these activities are profoundly changed in GF mice. These alterations in microbiome-sensitive gene expression patterns are associated with daily alterations in lipid, glucose and xenobiotic metabolism, protein turnover and redox balance, as revealed by hepatic metabolome analyses. Moreover, at the systemic level, daily changes in the abundance of biomarkers such as HDL cholesterol, free fatty acids, FGF21, bilirubin and lactate depend on the microbiome. Altogether, our results indicate that the microbiome is required for integration of liver clock oscillations that tune output activators and their effectors, thereby regulating metabolic gene expression for optimal liver function.
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| 18. |
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| 19. |
- Salvagno, G. L., et al.
(författare)
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Impact of different inhibitor reactivities with commercial factor VIII concentrates on thrombin generation
- 2007
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 13:1, s. 51-56
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Tidskriftsartikel (refereegranskat)abstract
- In order to describe the haemostatic role of a variation in inhibitor reactivity with different factor VIII (FVIII) concentrates, we have compared inhibitor titres against a panel of FVIII concentrates and correlated titre with the capacity to inhibit thrombin generation. Three plasma-derived concentrates were tested in vitro in mixing experiments with inhibitor plasmas from 11 patients with severe haemophilia A: Fanhdi, which contains von Willebrand factor (VWF) with a final ratio of approximately 1:1 (VWF IU per IU FVIII:Q; Haemate-P with a ratio of 2.5:1 and Hemofil-M containing only trace amounts of VWF. In addition, the recombinant FVIII concentrate Kogenate Bayer containing no VWF was included. Inhibitor titres and the capacity to generate thrombin were measured. A statistically significant difference in measured titres was found with the highest titres recorded against Hemofil-M. The inhibitor titres needed to inhibit 50% maximum thrombin generation were the lowest for Kogenate Bayer and the highest and similar for Fanhdi and Haemate-P with intermediate titres needed for inhibition of Hemofil-M. In this study, the thrombin generation assay provides additional indications for the role of VWF in the treatment of patients with inhibitors. The VWF-containing concentrates Fanhdi and Haemate-P, added to FVIII-deficient plasma with the presence of inhibitor, generate more thrombin than do the purified concentrates Hemofil-M and Kogenate Bayer.
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| 20. |
- Salvagno, G. L., et al.
(författare)
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Thrombin generation assay: a useful routine check-up tool in the management of patients with haemophilia?
- 2009
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Ingår i: Haemophilia. - : Wiley. - 1351-8216 .- 1365-2516. ; 15:1, s. 290-296
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Tidskriftsartikel (refereegranskat)abstract
- Severity assessment of patients with haemophilia A (HA) is traditionally based on FVIII activity (FVIII:C). Clinical phenotype of HA patients often differs between individuals with the same FVIII:C determined with clotting and chromogenic assays. The aim of this study was to assess the influence of the FVIII:C on thrombin generation (TG) assay parameters both in vitro and ex-vivo postinfusion plasma. For in-vitro approach, influence of FVIII:C was evaluated on TG parameters in several dilutions of a normal plasma pool with commercial FVIII-depleted-plasma (FVIIIDP) and in others experiments, adding increasing amounts of different commercial FVIII concentrates (Fanhdi, Haemate-P, Hemofil-M and Kogenate Bayer) to FVIIIDP. In a series of 50 postinfusion samples, from HA patients of different severity, we assayed TG and FVIII:C (chromogenic and clotting). In vitro experiments, the 50% of maximum TG peak (TGMP) was achieved using only 5% FVIII:C and the TGMP was obtained with 40% of normal VIII:C. Impaired response compared with normal plasma was found in FVIIIDP using addition of increasing amounts of different commercial FVIII concentrates. An overall good correlation between the two FVIII assays was observed (y = 0.9115x - 0.273, r = 0.975, P < 0.001); TGMP and the Lag-Phase-Time (LPT) provided some discrepant results when compared with the total range of FVIII:C measurements. In contrast, correlations for TGMP, LPT and endogenous thrombin potential were improved in samples restricted to FVIII:C < 5%. We conclude that TG parameters tentatively could be a tool to tailor the global haemostatic capacity in haemophilic patients.
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| 21. |
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| 22. |
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