Abstract: Microfluidic structures featuring substantially circular channels may be fabricated by embossing polymer sheets.

Abstract: The systems and methods described herein relate to a high-throughput flow apparatus. The apparatus is used with an array of wells, and is configured to impart a predetermined shear stress on cells cultured within each of the wells of the array of wells. The apparatus includes a plurality of mechanical tips. The plurality of mechanical tips each includes a head with a hemispheroid shape. The apparatus also includes a motor associated with at least one of plurality of mechanical tips. The motor is configured to drive the plurality of mechanical tips to impart the shear stress pattern in each of the wells.

Abstract: Microfluidic structures featuring substantially circular channels may be fabricated by embossing polymer sheets.

Abstract: Microfluidic structures featuring substantially circular channels may be fabricated by embossing polymer sheets.

Abstract: The systems and methods described herein relate to a high-throughput flow apparatus. The apparatus is used with an array of wells, and is configured to impart a predetermined shear stress on cells cultured within each of the wells of the array of wells. The apparatus includes a plurality of mechanical tips. The plurality of mechanical tips each includes a head with a hemispheroid shape. The apparatus also includes a motor associated with at least one of plurality of mechanical tips. The motor is configured to drive the plurality of mechanical tips to impart the shear stress pattern in each of the wells.

Abstract: A high-throughput flow system includes an array of wells and a separate mechanical tip positioned within each well. Each mechanical tip is separately actuated to impart a shear stress pattern. A separate sleeve may be associated with each tip for maintaining a predetermined distance between the tip and a floor of the tip's corresponding well, with each tip being rotatable within its corresponding sleeve. Alternatively, a separate post may be associated with each tip for maintaining a predetermined distance between the tip and a floor of the tip's corresponding well, with each tip being rotatable about its corresponding post.

Abstract: Microfluidic structures featuring substantially circular channels may be fabricated by embossing polymer sheets.

Abstract: Methods of fabricating microfluidic structures featuring substantially circular channels are provided. The methods involve (a) providing a patterned wafer comprising at least one exposed electrically conductive region and at least one exposed electrically insulating region; (b) electroplating an inverse channel portion with substantially semicircular cross section onto the wafer, thereby forming a first master mold; (c) employing the first master mold so as to emboss a channel portion in a first polymer sheet; and (d) aligning and bonding the first polymer sheet with a second polymer sheet having a corresponding channel portion such as to define a first channel with substantially circular cross section between the polymer sheets.

Abstract: The present invention provides methods and compositions for increasing the hematopoietic potential of a population of hematopoietic progenitor cells, vascular cells, and or hemogenic endothelium, by exposing the cells to at least one external biomechanical stimulus. More specifically, the application of shear stress to hematopoietic progenitor cells or endothelial cells stimulates hematopoiesis, with or without concurrent application of other extrinsic modulators of hematopoiesis.

Abstract: In one embodiment, a high-throughput flow system includes an array of wells and a separate mechanical tip positioned within each well. Each mechanical tip is separately actuated to impart a shear stress pattern.

Abstract: Microfluidic structures featuring substantially circular channels may be fabricated by embossing polymer sheets.

Abstract: The present invention is based upon the discovery that endothelial cells exposed to atheroprotectiveflow increase expression of the transcription factor KLF2 via a distinct flow-mediated signaling pathway and that this, in turn, modulates the activity of a series of genes that are responsible for maintaining the cells in an atherosclerosis-resistant state. By carrying out analyses to determine the extent to which endothelial cells are expressing these genes, a determination can be made concerning whether they are in a healthy state and factors can be examined for their effect on this state. In addition, the invention includes microarray plates or slides that can be used in carrying out such analyses.

Abstract: Arterial and venous smooth muscle cells are molecularly distinct from the earliest stages of angiogenesis through to adulthood. This distinction is revealed by expression on arterial cells (e.g., arterial endothelial cells, arterial smooth muscle cells) of a transmembrane ligand, called EphrinB2 whose receptor EphB4 is expressed on venous cells. Targeted disruption of the EphrinB2 gene prevents the remodeling of veins from a capillary plexus into properly branched structures. Moreover, it also disrupts the remodeling of arteries, suggesting that reciprocal interactions between pre-specified arterial and venous cells are necessary for angiogenesis. Expression of EphrinB2 in arterial cells (e.g.

Abstract: Arterial and venous smooth muscle cells are molecularly distinct from the earliest stages of angiogenesis through to adulthood. This distinction is revealed by expression on arterial cells (e.g., arterial endothelial cells, arterial smooth muscle cells) of a transmembrane ligand, called EphrinB2 whose receptor EphB4 is expressed on venous cells. Targeted disruption of the EphrinB2 gene prevents the remodeling of veins from a capillary plexus into properly branched structures. Moreover, it also disrupts the remodeling of arteries, suggesting that reciprocal interactions between pre-specified arterial and venous cells are necessary for angiogenesis. Expression of EphrinB2 in arterial cells (e.g.