Journal: Blood

Article Title: High shear-dependent loss of membrane integrity and defective platelet adhesion following disruption of the GPIb?-filamin interaction

doi: 10.1182/blood-2010-07-296194

Figure Lengend Snippet: Caspase-dependent cleavage of cytoskeletal proteins induces a shear-specific defect in platelet membrane tether stability. (A) DiIC12-labeled washed human platelets in the presence of 1 mg/mL ristocetin were perfused over human VWF-coated microchannels and allowed to adhere for 10 minutes in the absence of shear. Shear was applied (at a rate of 600 or 1800 s−1), and platelet adhesive behavior was captured using Metamorph software. Single frame fluorescence images (after subjecting to a low pass filter of 3) show the formation of long membrane tethers from ABT-737–treated (1μM) platelets, which is prevented by pretreatment with Q-VD-OPh (50μM). Scale bar represents 10 μm. (B) Quantitation of mean tether length from 3 independent experiments demonstrates a significant increase in membrane tether length in ABT-737–treated platelets compared with control and QV-D-OPh–treated platelets. ***P < .001. (C) DIC images of platelets demonstrating membrane tethers and the loss of discoid platelet morphology after treatment with ABT-737 and prevention by Q-VD-OPh are shown under the same shear conditions as in panel A. Scale bar represents 10 μm.

Article Snippet: Samples were washed and fixed as initially described in this paragraph, and DIC and fluorescent images were captured and overlayed using Metamorph software.

Techniques: Shear, Membrane, Labeling, Adhesive, Software, Fluorescence, Quantitation Assay, Control

Journal: Blood

Article Title: High shear-dependent loss of membrane integrity and defective platelet adhesion following disruption of the GPIb?-filamin interaction

doi: 10.1182/blood-2010-07-296194

Figure Lengend Snippet: Adhesion and spreading of transgenic mouse platelets to immobilized VWF under static conditions is unaffected by loss of filamin A interaction. (A) hGPIbαWT and hGPIbαFW platelets were allowed to adhere to human VWF (5 μg/mL) for 60 minutes in the presence of ristocetin (1.5 mg/mL), botrocetin (5 μg/mL), or botrocetin + Xia.B2 murine GPIbα blocking antibody (20 μg/mL). Results are mean (± SEM) from at least 4 independent experiments and demonstrate no significant difference in the total number of adherent platelets under all conditions tested. Ristocetin-dependent adhesion and botrocetin-dependent adhesion in the presence of Xia.B2 are identical and represent adhesion to human VWF mediated specifically by hGPIbα. (B) Platelet spreading on VWF (+ 1.5 mg/mL ristocetin) was analyzed from DIC images (at least 3 separate fields from 3 independent experiments) and demonstrated no significant difference between hGPIbαWT and hGPIbαFW platelets. Platelets treated with inhibitors of ADP and thromboxane (1 U/mL apyrase, a combination of 10μM MeSAMP and 100μM MRS2179, or MeSAMP/MRS2179 and 10μM indomethacin) demonstrated that integrin αIIbβ3 activation occurred directly downstream from GPIbα without a contribution from these secondary mediators. (C) Oregon Green fibrinogen binding to platelets adherent to human VWF (in the presence of 1.5 mg/mL ristocetin) was no different between hGPIbαWT and hGPIbαFW mice, indicating that integrin αIIbβ3 activation is unaffected by the loss of filamin A binding to GPIbα. DIC and fluorescent images were overlayed using Metamorph and are representative of 4 independent experiments. Scale bar represents 10 μm.

Article Snippet: Samples were washed and fixed as initially described in this paragraph, and DIC and fluorescent images were captured and overlayed using Metamorph software.

Techniques: Transgenic Assay, Blocking Assay, Activation Assay, Binding Assay

Journal: 3D Printing and Additive Manufacturing

Article Title: Investigation of Interlayer Interface Strength and Print Morphology Effects in Fused Deposition Modeling 3D-Printed PLA

doi: 10.1089/3dp.2020.0109

Figure Lengend Snippet: Custom slot design (top left) and close-up view of four-extrusion configuration layer preview showing the nozzle position where the layer seam occurs (top right). Dashed lines signify flat sections to be cut out for specimen fabrication that isolates extrusion interfaces. FDM tensile dog-bone specimen in various stages of the laser cutting preparation (bottom left). Experimental tensile test setup with USB camera video capture for DIC strain measurement (bottom right). DIC, digital image correlation.

Article Snippet: Strain was measured by a custom digital image correlation (DIC) system by using an Edmund Optics machine vision USB camera and open-source software.

Techniques: