Wnt signaling promotes hematoendothelial cell development from human embryonic stem cells.

Human embryonic stem cells (hESCs) provide an important means to effectively study soluble and cell-bound mediators that regulate development of early blood and endothelial cells in a human model system. Here, several complementary methods are used to demonstrate canonical Wnt signaling is important for development of hESC-derived cells with both hematopoietic and endothelial potential. Analyses using both standard flow cy-tometry, as well the more detailed high-throughput image scanning flow cytometry, characterizes sequential development of distinct early developing CD34(bright)CD31(+)Flk1(+) cells and a later population of CD34(dim)CD45(+) cells.

Efficient and stable transgene expression in human embryonic stem cells using transposon-mediated gene transfer.

Efficient and stable genetic modification of human embryonic stem (ES) cells is required to realize the full scientific and potential therapeutic use of these cells. Currently, only limited success toward this goal has been achieved without using a viral vector. The Sleeping Beauty (SB) transposon system mediates nonviral gene insertion and stable expression in target cells and tissues.

Lessons from an evaluation of a boater outreach program for manatee protection.

Watercraft collisions account for 25-30% of manatee deaths annually in Florida. Education and outreach interventions for boaters are strategies for reducing manatee mortality. We evaluated the effectiveness of the Manatee Watch program by surveying primary boat users whose boats were approached by Manatee Watch.

Understanding barriers to implementation of an adaptive land management program.

The Florida Fish and Wildlife Conservation Commission manages over 650,000 ha, including 26 wildlife management and environmental areas. To improve management, they developed an objective-based vegetation management (OBVM) process that focuses on desired conditions of plant communities through an adaptive management framework. Our goals were to understand potential barriers to implementing OBVM and to recommend strategies to overcome barriers.

Hematopoietic engraftment of human embryonic stem cell-derived cells is regulated by recipient innate immunity.

Human embryonic stem cells (hESCs) provide an important means to characterize early stages of hematopoietic development. However, the in vivo potential of hESC-derived hematopoietic cells has not been well defined. We demonstrate that hESC-derived cells are capable of long-term hematopoietic engraftment when transplanted into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice.

Cytokine requirements differ for stroma and embryoid body-mediated hematopoiesis from human embryonic stem cells.

Objective: Human embryonic stem (ES) cells can be induced to differentiate into hematopoietic lineages either by stromal cell coculture or by formation of embryoid bodies (EBs). Here, we better characterize cell-bound and secreted factors that support this hematopoietic development.

Methods: Human ES cells either cocultured on the mouse bone marrow cell line S17, or allowed to form EBs, were induced to differentiate in the presence of serum, serum-free conditions, and serum-free media supplemented with defined cytokines.

Family or friends: who plays a greater supportive role for Latino college students?

This study compared the relative contribution of perceived family and friend support to psychological well-being and distress and examined whether family or friend support moderated the effects of stress on psychological adjustment in 338 Latino (228 Mexican American, 110 Central American) college students from a predominantly Latino university. Two multiple regressions, controlling for gender, socioeconomic level, acculturation level, and stresses (generic college, acculturative, and minority status), showed that friend support made a slightly greater contribution to well-being than family support, and friend support and not family support protected against psychological distress. Neither family nor friend support moderated the effects of stress on psychological adjustment.