US and foreign alloy cross-reference database

Marshall Space Flight Center and other NASA installations have a continuing requirement for materials data from other countries involved with the development of joint international Spacelab experiments and other hardware. This need includes collecting data for common alloys to ascertain composition, physical properties, specifications, and designations. This data is scattered throughout a large number of specification statements, standards, handbooks, and other technical literature which make a manual search both tedious and often limited in extent. In recognition of this problem, a computerized database of information on alloys was developed along with the software necessary to provide the desired functions to access this data. The intention was to produce an initial database covering aluminum alloys, along with the program to provide a user-interface to the data, and then later to extend and refine the database to include other nonferrous and ferrous alloys

Marketing strategy:a history of the next decade

Editoria

Apoptosome activation, an important molecular instigator in 6-mercaptopurine induced Leydig cell death.

Leydig cells are crucial to the production of testosterone in males. It is unknown if the cancer chemotherapeutic drug, 6-mercaptopurine (6 MP), produces Leydig cell failure among adult survivors of childhood acute lymphoblastic leukemia. Moreover, it is not known whether Leydig cell failure is due to either a loss of cells or an impairment in their function. Herein, we show, in a subset of childhood cancer survivors, that Leydig cell failure is related to the dose of 6 MP. This was extended, in a murine model, to demonstrate that 6 MP exposure induced caspase 3 activation, and the loss of Leydig cells was independent of Bak and Bax activation. The death of these non-proliferating cells was triggered by 6 MP metabolism, requiring formation of both cytosolic reactive oxygen species and thiopurine nucleotide triphosphates. The thiopurine nucleotide triphosphates (with physiological amounts of dATP) uniquely activated the apoptosome. An ABC transporter (Abcc4/Mrp4) reduced the amount of thiopurines, thereby providing protection for Leydig cells. The studies reported here demonstrate that the apoptosome is uniquely activated by thiopurine nucleotides and suggest that 6 MP induced Leydig cell death is likely a cause of Leydig cell failure in some survivors of childhood cancer