5 research outputs found

    Multicentre evaluation of 5B9, a monoclonal anti-PF4/heparin IgG mimicking human HIT antibodies, as an internal quality control in HIT functional assays: Communication from the ISTH SSC Subcommittee on Platelet Immunology.

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    Functional tests for the diagnosis of heparin-induced thrombocytopenia (HIT) exhibit variable performance. We evaluated in a multicenter study whether 5B9, a monoclonal anti-PF4/heparin IgG mimicking human HIT antibodies, could be used as an internal quality control. 5B9 was sent to 11 laboratories in seven countries, and six initial concentrations ranging from 10 to 400 μg/mL were tested by heparin-induced platelet activation assay (HIPA), serotonin release assay (SRA), platelet aggregation test (PAT), flow cytometry (FC), or heparin-induced multiple-electrode aggregometry (HIMEA). Each method was evaluated in three different laboratories using experimental procedures identical to those usually applied for the diagnosis of HIT by testing platelets from 10 different healthy donors. The procedures used varied among the laboratories, particularly when platelet-rich plasma and whole blood were used. Nevertheless, positive results were obtained with at least 100 μg/ml of 5B9 for most donors tested by all centers (except one) performing HIPA, SRA, or HIMEA. FC and PAT results were more heterogeneous. FC results from one center that used washed platelets preincubated with PF4 were positive with all donors at 50 µg/ml 5B9, but at least 200 μg/ml of 5B9 were required to activate cells with most donors tested using PAT. This study confirms that HIT functional tests are not well standardized and exhibit variable sensitivity for the detection of platelet-activating antibodies. However, 5B9 is a potentially useful tool to standardize functional tests, to select responding platelet donors, and consequently to improve the performance of these assays and comparability between laboratories

    Evolution of Single-Particle Energies for N=9 Nuclei at Large N/Z

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    We have studied the nucleus 14B using the 13B(d,p)14B and 15C(d,3He)14B reactions. The two reactions provide complementary information about the negative-parity 1s1/2 and 0d5/2 neutron single-particle states in 14B. The data from the (d,p) reaction give neutron-spectroscopic strengths for these levels, and the (d,3He) results confirm the existence of a broad 2- excited state suggested in the literature. Together these results provide estimates of the sd-shell neutron effective single-particle energies in 14B

    Features of cryptococcosis among 652 HIV-seronegative individuals in France: a cross-sectional observational study (2005-2020)

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    International audienceObjectives: We aimed to describe features and outcomes of cryptococcosis among HIV-seronegative individuals in a large surveillance network for cryptococcosis in France.Methods: We included incident cases of cryptococcosis in HIV-seronegative individuals from 2005 to 2020. We compared patient characteristics, disease presentations, cryptococcal antigen (CrAg) results, and induction antifungal treatments according to underlying disease. We examined factors associated with 90-day mortality. Among patients with disseminated infections, we investigated whether receipt of flucytosine and polyene combination was associated with lower mortality.Results: Among 652 individuals, 209 (32.1%) had malignancy, 130 (19.9%) were solid-organ transplant (SOT) recipients, 204 (31.3%) had other immunocompromising conditions, and 109 (16.7%) had no reported underlying factor. The commonest presentations were disseminated infections (63.3%, 413/652) and isolated pulmonary infections (25.3%, 165/652). SOT patients were most likely to have disseminated infections and a positive serum CrAg result. Patients with malignancy were older and less likely to receive a flucytosine-containing regimen for disseminated infections than others (58.7%, 78/133 vs. 73.2%, 194/265, p=0.029). The crude 90-day case-fatality ratio was 27.2% (95%CI: 23.5%-31.1%). Age ≥60 years (aOR: 2.75 [1.78-4.26], p<0.001), meningitis/fungaemia (aOR: 4.79 [1.80-12.7], p=0.002), and malignancy (aOR: 2.4 [1.14-5.07], p=0.02) were associated with higher 90-day mortality. Receipt of flucytosine and polyene combination was associated with lower 90-day mortality (aOR: 0.40 [0.23-0.71], p=0.002) in multivariable analysis and inverse probability of treatment weighted analysis (aOR: 0.45 [0.25-0.80], p=0.006).Conclusions: HIV-seronegative individuals with cryptococcosis comprise a wide range of underlying conditions with different presentations and outcomes, requiring a tailored approach to diagnosis and management
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