Current status of platelet manufacturing in 3D or bioreactors.

Blood shortages for transfusion are global issues of grave concern. As in vitro manufactured platelets are promising substitutes for blood donation, recent research has shown progresses including different cell sources, different bioreactors, and three-dimensional materials. The first-in-human clinical trial of cultured platelets using induced pluripotent stem cell-derived platelets began in Japan and demonstrated its quality, safety, and efficacy. A novel bioreactor with fluid motion for platelet production has been reported. Herein, we discuss various cell sources for blood cell production, recent advances in manufacturing processes, and clinical applications of cultured blood.

Rapid release and changing sources of Pb in a mountainous watershed during extreme rainfall events.

Although atmospheric Pb is known to accumulate in forest soils over time, little is known about the hydrologic Pb export from mountain forest soils. Short-term changes in Pb release and its sources during monsoon rainfall events were investigated in a mountainous watershed in the northern extreme of South Korea by combining intensive storm sampling with measurements of Pb concentrations and isotope ratios in soils and size-fractionated sediments. Biweekly monitoring of forest and agricultural streams showed relatively low dissolved Pb concentrations compared to those found in precipitation. Particulate Pb concentrations in both streams were higher than the dissolved concentrations and increased rapidly during rainfall events. Particulate Pb concentrations were substantially higher in the agricultural stream; the highest concentrations were associated with silt-size sediment followed by sand. A comparison of (206)Pb/(207)Pb and (208)Pb/(206)Pb among sediment fractions and source soils indicated that major sources for silt- and sand-associated Pb in the agricultural stream change between streambank and cropland soils, whereas Pb in the forest stream is primarily derived from forest floors. The results suggest that Pb isotopes can be efficiently applied to tracing short-term changes in sediment and Pb sources and that extreme rainfall events can significantly increase Pb mobilization from erosion-prone mountain soils.