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Myoblast cell cultures have been widely employed in conventional (1g) studies of biological processes because characteristics of intact muscle can be readily observed in these cultured cells. We decided to investigate the effects of spaceflight on muscle by utilizing a well characterized myoblast cell line (L8 rat myoblasts) as cultured in the recently designed Space Tissue Loss Flight Module "A" (STL-A). The STL-A is a "state of the art," compact, fully contained, automated cell culture apparatus which replaces a single mid-deck locker on the Space Shuttle. The L8 cells were successfully flown in the STL-A on the Space Shuttle STS-45 mission. Upon return to earth, reculturing of these spaceflown L8 cells (L8SF) resulted in their unexpected failure to fuse and differentiate into myotubes. This inability of the L8SF cells to fuse was found to be a permanent phenotypic alteration. Scanning electron microscopic examination of L8SF cells growing at 1g on fibronectin-coated polypropylene fibers exhibited a strikingly different morphology as compared to control cells. In addition to their failure to fuse into myotubes, L8SF cells also piled up on top of each other. When assayed in fusion-promoting soft agar, L8SF cells gave rise to substantially more and larger colonies than did either preflight (L8AT) or ground control (L8GC) cells. All data to this point indicate that flying L8 rat myoblasts on the Space Shuttle for a duration of 7-10 d at subconfluent densities results in several permanent phenotypic alterations in these cells.

Topical applications of each of the naturally occurring juvenile hormones I, II, and III induced de-alation in virgin female Solenopsis invicta , whereas ecdysterone had no effect. De-alation occurred within 6–8 h following application when one ng or greater quantities of any of the 3 natural juvenile hormones were applied, with longer time periods required at lower doses. The ED50 values for juvenile hormones I, II, and III for inducing dealation within 24 h, were 0.44, 0.25, and 0.32 ng per insect, respectively. Oviposition occurred 3–6 days following JH application. De-alation was not observed in male alates following topical applications of JH.

The main purpose of this work was to isolate the components in acetone soluble lipids of lepromas of the nine-banded armadillo by high performance liquid chromatography (HPLC), and then to examine the mass spectrometric characteristics of the two peaks (molecular weights 2000 and 1600) found by HPLC. The armadillo had been inoculated with Mycobacterium leprae isolated from a mangabey monkey with naturally acquired leprosy. According to the results of HPLC, gas liquid chromatographic and mass spectral analyses, the GPC peak I lipid at 2000 D was identified as phenolic glycolipid and the GPC peak II lipid at 1600 D, as phthiocerol dimycocerosate. It was thought that the GPC peak I lipid and the GPC peak II lipid were included in the spherical droplets (peribacillary substance) around M. leprae. It was concluded that the microorganisms causing leprosy-like changes in the mangabey monkey were either M. leprae or a very closely related bacillus.