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Astronaut Edgar Mitchell Claims Alien Cover-up

Dr. Edgar Mitchell is a veteran of the Apollo 14 mission and he was the sixth man to walk on the Moon. Dr. Mitchell also insists that aliens have visited Earth and that governments are actively covering it up. "I happen to have been privileged enough to be in on the fact that we've been visited on this planet and the UFO phenomena is real," Dr Mitchell said. "It's been well covered up by all our governments for the last 60 years or so, but slowly it's leaked out and some of us have been privileged to have been briefed on some of it. "I've been in military and intelligence circles, who know that beneath the surface of what has been public knowledge, yes - we have been visited. Reading the papers recently, it's been happening quite a bit." Dr Mitchell, who has a Bachelor of Science degree in aeronautical engineering and a Doctor of Science degree in Aeronautics and Astronautics claimed Roswell was real and similar alien visits continue to be investigated. He told the astonished Kerrang! radio host Nick Margerrison: "This is really starting to open up. I think we're headed for real disclosure and some serious organisations are moving in that direction." NASA issued a quick denial. In a statement, a spokesman said: "NASA does not track UFOs. NASA is not involved in any sort of cover up about alien life on this planet or anywhere in the universe. "Dr Mitchell is a great American, but we do not share his opinions on this issue." If Dr. Mitchell is correct about a cover-up than this is exactly the type of denial one would expect NASA to make. You can listen to the interview with Dr. Mitchell where he discusses the UFO phenomena here. Permalink | Recent Headlines | News Feeds Read more…

Stem Cells Get A Grip

15.12.2006 19:10 Science - Source: ScienceDaily Headlines

In real estate, it's location, location, location. In stem cells, it's niche, niche, niche.

Stems cells are regulated by "intrinsic factors" but it's also becoming increasingly clear that their "stemness" depends on the unique microenvironment called the stem cell niche.

No adult or somatic stem cells have a more complex niche life than hematopoietic stem cells, which give rise to all the different types of blood and immune cells. The bone marrow is their niche. It's a crowded neighborhood, teeming with different cell types such as fibroblasts, adipocytes, macrophages, and endothelial cells. Hematopoietic stem cells also share their bone marrow niche with osteoblasts, the body's bone-forming cells, which are derived from a different stem cell population called bone marrow stromal cells. The two stem cells lines probably have a common progenitor but for now scientists can only regard hematopoietic stem cells and osteoblasts as niche neighbors. But it's a very close relationship, as researchers in the National Institute of Child Health & Human Development laboratory of Jennifer Lippincott-Schwartz now reveal in great detail.

Earlier reports had established that osteoblasts are a crucial component of the hematopoietic stem cell niche and that physical contact with osteoblasts was vital for their survival. The Lippincott-Schwartz lab used live cell imaging techniques to see what happens when the two cell types are put together, directing their attention in particular at the point of cell-cell contact, and how it affects the cellular and molecular relationship of the two cell types.

The NIH researchers observed dynamic amoeboid motility toward the osteoblasts by both human CD34+ hematopoietic progenitor cells and KG1 cells, which are a hematopoietic subset of myeloid progenitors. The progenitor cells assumed a polarized morphology with a leading edge structure and a foot-like "special domain" projection from the cell's trailing edge called a uropod. It was through this foot that the hematopoietic stem cells took hold of the osteoblasts. The uropod contact point was enriched in the cholera toxin B subunit, a lipid raft molecule, as well as the stem cell marker CD133.

The researchers had seeded the outside of the progenitor cells with microscopic markers, quantum dot nanocrystals, and watched as the dots were taken into the cells and delivered specifically to the uropod domain at the point of contact. Interestingly, time-lapse microscopy detected transfer of the quantum dots from the progenitor cells to the osteoblastic cells, suggesting an intercellular transfer of cell-associated molecules. Immune cells are known to transfer cell-surface molecules during cell-cell interactions so a similar intercellular transfer between hematopoietic progenitors and osteoblasts could be of broad biological significance, the researchers say. Further studies will explore how these close neighbors pull together in the hematopoietic niche.