To diagnose heparin-induced thrombocytopenia (HIT), detection of platelet-activating antibodies (HIT antibodies) is crucial. However, serum platelet activation profiles vary across patients and depend on test conditions. We evaluated the association between clinical outcomes and platelet-activating profiles assessed by a platelet microparticle assay (PMA), which detects activation of washed platelets induced by HIT antibodies, in 401 consecutive patients clinically suspected of having HIT. We made modifications to the assay, such as donor selection for washed platelets that increased sensitivity. Serum that activated platelets at a therapeutic (but not high) heparin concentration was defined as positive. Of these, serum that activated platelets within 30 minutes or in the absence of heparin was defined as strongly positive. The remaining samples were considered weakly positive. As a result, 97 % and 93 % of patients who tested strongly and weakly positive had clinical profiles consistent with HIT, respectively. The incidence of thromboembolic events (TEEs) after heparin exposure in patients who tested strongly positive, weakly positive, and negative was 61 %, 40 %, and 29 %, respectively. Among patients who did not experience a TEE on the day HIT was suspected, there was no significant difference in the cumulative incidence of subsequent TEEs between patients who tested strongly and weakly positive when argatroban was initiated on the same day (19.0 % vs 7.1 %, p=0.313), but there was a significant difference when argatroban therapy was delayed by one or more days (61.1 % vs 17.6 %, p=0.007). The modified PMA is effective in diagnosing HIT and identifying patients at high risk for HIT-associated TEEs.

We report the first in situ synthesis of copper nanoparticles (CuNPs) within the interlayer space of inorganic layered semiconductor (titania nanosheets; TNSs) transparent films.

The synthesis of silver nanoparticles (AgNPs) within the interlayer space of transparent layered titania nanosheet (TNS) films is investigated. A considerable number of silver ions (≈70% against the cation exchange capacity of the TNS) are intercalated in the TNS films using methyl‐viologen‐containing TNSs as a precursor. The silver ion (Ag + )‐containing TNS films are treated with aqueous sodium tetrahydroborate (NaBH 4 ), resulting in a gradual color change to bright blue. Various structural analyses clearly show that crystalline AgNPs are generated within the interlayer space of the TNSs. The NaBH 4 ‐treated films show intense and characteristic near‐infrared (NIR) extinction spectra up to 1800 nm. The stability of the AgNPs within the TNS against oxygen and moisture is also investigated, and 96% and 82% of the AgNPs remain after standing in air for 1 month and 1 year, respectively. The NIR extinctions of the AgNP‐containing TNS films are further extended by employing different preparation procedures, for example, using sintered TNS films as starting materials and irradiating the Ag + ‐containing TNSs with ultraviolet (UV) light. The obtained AgNP‐containing TNS films exhibit photochemical activities in the production of hydrogen from ammonia borane under visible‐light irradiation and the decomposition of nitrogen monoxide under UV‐light irradiation.

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