Biomedical application of TiO2NPs can cause arterial thrombotic risks through triggering procoagulant activity, activation and aggregation of platelets.

BACKGROUND: Titanium dioxide nanoparticles (TiO2NPs) are widely used in medical application. However, the relevant health risk has not been completely assessed, the potential of inducing arterial thrombosis (AT) in particular. METHODS: Alterations in platelet function and susceptibility to arterial thrombosis induced by TiO2NPs were examined using peripheral blood samples from healthy adult males and an in vivo mouse model, respectively. RESULTS: Here, using human platelets (hPLTs) freshly isolated from health volunteers, we demonstrated TiO2NP treatment triggered the procoagulant activity of hPLTs through phosphatidylserine exposure and microvesicles generation. In addition, TiO2NP treatment increased the levels of glycoprotein IIb/IIIa and P-selectin leading to aggregation and activation of hPLTs, which were exacerbated by providing physiology-mimicking conditions, including introduction of thrombin, collagen, and high shear stress. Interestingly, intracellular calcium levels in hPLTs were increased upon TiO2NP treatment, which were crucial in TiO2NP-induced hPLT procoagulant activity, activation and aggregation. Moreover, using mice in vivo models, we further confirmed that TiO2NP treatment a reduction in mouse platelet (mPLT) counts, disrupted blood flow, and exacerbated carotid arterial thrombosis with enhanced deposition of mPLT. CONCLUSIONS: Together, our study provides evidence for an ignored health risk caused by TiO2NPs, specifically TiO2NP treatment augments procoagulant activity, activation and aggregation of PLTs via calcium-dependent mechanism and thus increases the risk of AT.

Characterization of complete mitogenome data of two flies (Diptera) as orchid pollinators from China.

The Diptera insects have important ecological functions. Many plants rely on Diptera insects for pollination, and they play an important role in Co-evolution with plants. We described the detailed characteristics across the complete mitogenome sequences of Desmometopa sabroskyi Brake, 2003 (Diptera: Milichiidae) and an unidentified species of Gampsocera (Diptera: Chloropidae), which are pollinators of orchid species. Sequences were assembled and annotated using the reference genomes of Phyllomyza sp. (OP612805) and Elachiptera insignis (OP612812) available in Genbank. The complete mitogenomes of D. sabroskyi and Gampsocera sp. are 15,841 bp and 16,036 bp in length, respectively. Both mitogenomes include 37 genes consisting of 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs), and one noncoding region (NCR). The mitogenome data would better contribute to species identification, taxonomy, phylogenetics, and evolutionary analysis of Diptera insects. .