Natto, steamed soybeans fermented by Bacillus subtilis natto, is a traditional Japanese food. We derived a purified protein layer, called NKCP as a trade mark, from B. subtilis natto fermentation. In the present study, we examined the fibrinolytic and antithrombotic effects of NKCP and identified its active component to clarify the fibrinolytic effect of NKCP observed in preliminary clinical trials previously. The active component of NKCP was identified as a 34-kilodalton protein designated bacillopeptidase F. NKCP showed direct degradation of artificial blood clot in saline. The protease activity, accounting for the fibrinolytic effect of NKCP, was examined with a chromogenic substrate for plasmin. Dose-dependent prolongations of both prothrombin time and active partial thromboplastin time were observed in rats with intra-duodenum administration of NKCP. Our in vitro and in vivo studies suggest that NKCP has both a fibrinolytic effect and an antithrombotic effect similar to heparin. Because NKCP is derived from food and has safety data demonstrated by previous animal experiments and preliminary clinical trials, NKCP is considered as safe for clinical use.

In vehicle-to-pedestrian collisions, the characteristics of a vehicle's frontal shape and structural stiffness have a significant influence on the kinematics and injury risk of the pedestrian's body regions. In the present study, the kinematic behaviour and injury risk of the pedestrians were investigated in collisions against vehicles with different frontal shapes. The THUMS (Total HUman Model for Safety) pedestrian finite element (FE) model was used and impacted by three different types of vehicle FE models (passenger car, one-box vehicle and sport-utility vehicle [SUV]) representing the different frontal shapes at 40 km/h. In the simulation with the passenger car-to-pedestrian impact, the pedestrian wrapped around the hood, and the resulting bending moment of the lower extremity and head injury criterion (HIC) value were high. In the simulation with the one-box vehicle-to-pedestrian impact, the pedestrian's upper torso was directly hit by the front end of the vehicle. The pelvis and chest had contact with the stiff vehicle frontal panel, resulting in a high stress being observed on the rib cage. In the simulation with the SUV-to-pedestrian impact, the force of the pelvis was high due to the contact with the vehicle hood's leading edge. The results indicated that the frontal shape of the vehicle has a large effect on the pedestrian kinematic behaviour, including the impact velocity of the pelvis, chest, and head against the vehicle. Moreover, the stiffness of the vehicle structure can affect the deformation mode of the human body segments, such as the lower extremities and the rib cage. The injury predictions for each body region from the FE analyses agreed with observations from pedestrian accidents involving a car, one-box vehicle and SUV, respectively.

We present a rare autopsy case of fatal anaphylactic shock following fluorescein angiography. A 71-year-old Japanese woman undergoing retinal angiography to evaluate diabetic retinopathy died immediately after an injection of sodium fluorescein. Forensic autopsy and post-mortem biochemical analyses revealed an elevated serum level of tryptase which, in the absence of morphologic changes suggesting injury or disease, confirmed the diagnosis of fatal anaphylactic shock. Although serious adverse effects are rare after fluorescein angiography, patients should be observed, with appropriate resuscitation equipment available, for several hours after the administration of fluorescein.