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Background: A link between venous thromboembolism (VTE) and air travel has been recently discussed, so the present study aimed to clarify the characteristics of acute pulmonary thromboembolism (PTE) associated with air travel in Japan., Methods and Results: The study group comprised 36 patients with acute PTE associated with air travel. Patients' characteristics, clinical risk factors for VTE and coagulation abnormalities were investigated, and compared with a group of PTE not associated with travel. Of the 36 cases, 30 cases were female, 34 were over 40 years of age and all had flown more than 6 h. Two-thirds of all cases did not leave their seats during the flight. Of the patients, 44% had no clinical risk factors for VTE or coagulation abnormalities. Idiopathic PTE (ie, PTE without clinical risk factors or coagulation abnormalities) was significantly more common in the air travel group., Conclusion: Acute PTE associated with air travel in Japan is common in elderly women and may occur without any clinical risk factors for VTE or coagulation abnormalities. Remaining seated throughout the flight increases the risk.

Background: The effects of lysophosphatidylcholine (LPC) on electrophysiological activities and intracellular Ca2+ concentration ([Ca2+]i) were investigated in coronary arterial smooth muscle cells (CASMCs)., Methods and Results: The patch clamp techniques and Ca2+ measurements were applied to cultured rabbit CASMCs. The membrane potential was -46.0+/-5.0 mV, and LPC depolarized it. Replacement of extracellular Na+ with NMDG+ hyperpolarized the membrane and antagonized the depolarizing effects of LPC. In Na+-, K+-, or Cs+-containing solution, the voltage-independent background current with reversal potential (E(r)) of approximately +0 mV was observed. Removal of Cl- failed to affect it. When extracellular cations were replaced by NMDG+, E(r) was shifted to negative potentials. La3+ and Gd3+ abolished the background current, but nicardipine and verapamil did not inhibit it. In Na+-containing solution, LPC induced a voltage-independent current with E(r) of approximately +0 mV concentration-dependently. Similar current was recorded in K+- and Cs+-containing solution. La3+ and Gd3+ inhibited LPC-induced current, but nicardipine and verapamil did not inhibit it. In cell-attached configurations, single-channel activities with single-channel conductance of approximately 32pS were observed when patch pipettes were filled with LPC. LPC increased [Ca2+]i as the result of Ca2+ influx, and La3+ completely antagonized it., Conclusions: These results suggest that (1) nonselective cation current (I(NSC)) contributes to form membrane potentials of CASMCs and (2) LPC activates I(NSC), resulting in an increase of [Ca2+]i. Thus, LPC may affect CASMC tone under various pathophysiological conditions such as ischemia.