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BACKGROUND The application of riboflavin/UV-based pathogen inactivation (PI) to whole blood (WB) is currently limited by its negative impact on red blood cell (RBC) quality. The generation of reactive oxidative species in RBC products contributes to increased hemolysis. This study evaluated the impact of deoxygenation of WB prior to riboflavin/UV light treatment versus deoxygenation of RBC concentrates after PI treatment by monitoring RBC in vitro quality parameters. STUDY DESIGN AND METHODS Six ABO-matched WB units were pooled and split. Within three pairs, one unit was treated with riboflavin/UV light while the other was kept as an untreated control prior to manufacture into red cell concentrates (RCCs). The first pair (Cntr; Cntr-PI) served as the normoxic controls. Deoxygenation was performed at the RCC level for the second pair (RCCdeox; PI-RCCdeox), and at the WB level of the third pair (WBdeox; WBdeox-PI). In vitro qualities of the respective RBC units were assessed throughout storage. RESULTS The data for the Cntr and Cntr-PI units were comparable to previous reports. The PI-RCCdeox units exhibited worse in vitro quality for most parameters tested compared to Cntr-PI and WBdeox-PI units throughout storage. Hemolysis and microvesicle release was significantly (p

BACKGROUND Leukoreduced whole blood (LR-WB) has received renewed attention as alternative to component-based transfusion in trauma. According to the manufacturer's instructions, leukoreduction should be carried out within 8 h after collection. This study assessed impact of (1) WB collection bag, (2) LR filtration, and (3) timing of filtration on in vitro quality. STUDY DESIGN AND METHODS WB collected into different vendor bags was held at room temperature for 16 h but

BACKGROUND Biochemical analyses of mechanisms triggered in platelets (PLTs) upon pathogen inactivation (PI) are crucial to further understand the impact of PI on PLT functionality and, subsequently, quality. STUDY DESIGN AND METHODS PLT concentrates (PCs) were split into four small illumination bags: 1) untreated control, 2) treated with riboflavin and ultraviolet light (RF/UV), and spiked with 3) solvent control dimethyl sulfoxide and 4) p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 before RF/UV treatment. Flow cytometry was used to monitor PLT mitochondrial potential (ΔΨm); generation of intracellular reactive oxygen species (ROS); and release of microvesicles (MVs), mitochondria (MT), and MVs containing MT (MVs/MT). Quantitative polymerase chain reaction (qPCR) was used to quantify extracellular mitochondrial DNA (mtDNA). Translocation of selected mitochondrial proteins was analyzed in subcellular fractions by immunoblot. RESULTS RF/UV treatment triggered an increased mitochondrial translocation of both Bax and Bid (p

BACKGROUND Missed detection of Staphylococcus epidermidis contamination in platelet (PLT) storage bags by the standard 24-hour-postcollection BacT/ALERT screening test has been documented. A slow growth rate and the strong tendency of this bacterium to adhere to surfaces can contribute to missed detection of the pathogen. STUDY DESIGN AND METHODS Topography of two different PLT storage bag surfaces, textured (rough) and smooth surfaces of Terumo 80440 bags (designated A15), was studied. Adhesion of biofilm-positive and -negative S. epidermidis strains on these surfaces was evaluated under static conditions. Quality of stored PLTs in A15 bags under blood bank conditions was compared for two different bag orientations (rough vs. smooth surface down) on Days 2, 5, and 7 of storage. PLT adhesion on the surfaces was evaluated after 7 days of storage. RESULTS Bacterial adhesion and biofilm formation were significantly higher on the rough surfaces of A15 bags compared to the smooth surfaces. After 7 days of storage in A15 bags, PLTs showed similar metabolite levels, pH, and response capacity in the bags with different orientation and more PLT adhesion and aggregation was observed on rough surfaces. CONCLUSION Higher bacterial adhesion on rough surfaces can contribute to missed detection of bacterial strains that tend to adhere on surfaces. PLT adhesion and aggregation on rough surfaces can affect the quality and safety of PLTs by promoting more bacterial adhesion and biofilm formation on surfaces.

Reaction-bonded B4C (RBBC) was fabricated through molten Si infiltrating porous B4C preforms. A preform with a 75% relative green density was obtained by mixing two different sized B4C powders. Carbon black added to the preform slightly reduces average pore size, but increases porosity. RBBC ceramics showed a dense and homogeneous microstructure. Vickers hardness was about 15 GPa for RBBC fabricated from a single type of B4C powder and could reach 22–23 GPa for the carbon-added samples after infiltration. Morphological evolution and the influence of the microstructure on the Vickers hardness were investigated and discussed.

Sodium borosilicate glass powder with the Si:B:Na molar ration of 53:44:6 has been developed and used as the solder to join sintered SiC ceramics. The coefficient of thermal expansion of the glass matches the silicon carbide substrate well at low temperature, and the wettability of the solder on SiC substrate becomes excellent above 1150°C. The 4-point bending strength of the joint reaches 218 ± 23 MPa at room temperature and the joint strength at 400°C can be kept at 154 ± 35 MPa. The microstructure, compositions, and interfacial properties were studied. Results showed that a good adhesion between SiC substrate and the solder layer was achieved.

The grafted copolymer (SBS-g-MBP) with different grafting ratio, synthesized by our laboratory, was irradiated by ultraviolet (UV) radiation with different time. The structure of SBS-g-MBP before and after UV exposure was characterized by Fourier transform infrared spectrometer, and the results confirmed that the UV-crosslinked structure was formed. The gel fraction before and after UV exposure was discussed, and the results indicated that the gel fraction increased with both exposure time and grafting ratio, and it also indicated the gel fraction was affected mainly by the exposure time. Furthermore, the results of scanning electron microscopy showed that the mode of fracture surfaces transmitted gradually from tough fracture to brittle fracture. The differential scanning calorimetry and thermal gravimetric analyzer indicated that the crosslinking has taken place in the polybutadiene block, and the thermal property was improved after UV exposure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The lung alveolar surface is covered by two morphologically and functionally distinct cells: alveolar epithelial cell types I and II (AEC I and II). The functions of AEC II, including surfactant release, cell differentiation and ion transport, have been extensively studied. However, relatively little is known regarding the physiological functions of AEC I. Global gene expression profiling of freshly isolated AEC I and II revealed that many genes were differentially expressed in AEC I. These genes have a diversity of functions, including cell defence. Nine out of 10 selected genes were verified by quantitative real-time PCR. Two genes, apolipoprotein E (Apo E) and transferrin, were further characterized and functionally studied. Immunohistochemistry indicated that both proteins were specifically localized in AEC I. Up-regulation of Apo E and transferrin was observed in hyperoxic lungs. Functionally, Apo E and transferrin play a protective role against oxidative stress in an animal model. Our studies suggest that AEC I is not just a simple barrier for gas exchange, but a functional cell that protects alveolar epithelium from injury.

Background Pathogen inactivation (PI) accelerates the platelet (PLT) storage lesion, including apoptotic-like changes. Proteomic studies have shown that phosphorylation levels of several kinases increase in PLTs after riboflavin and UV light (RF-PI) treatment. Inhibition of p38MAPK improved in vitro PLT quality, but the biochemical basis of this kinase's contribution to PLT damage requires further analysis. Study Design and Methods In a pool-and-split design, apheresis PLT concentrates were either treated or kept untreated with or without selected kinase inhibitors. Samples were analyzed throughout 7 days of storage, monitoring in vitro quality variables including phosphatidylserine exposure, degranulation, and glucose metabolism. Changes in the protein expression of Bax, Bak, and Bcl-xL and the activities of caspase-3 and -9 were determined by immunoblot analysis and flow cytometry, respectively. Results The expression levels of the proapoptotic proteins Bax and Bak, but not the antiapoptotic protein Bcl-xL, were significantly increased after the RF-PI treatment. This trend was reversed in the presence of p38MAPK inhibitor SB203580. As a result of increasing proapoptotic protein levels, caspase-3 and -9 activities were significantly increased in RF-PI treatment during storage compared with control (p