The systematic study of cellular reactions to purified chemical fractions of the tubercle bacillus was first demonstrated by Sabin and her co-workers.'5 16, 17, 18 These chemically purified derivatives were prepared by Anderson of Yale. The above studies have contributed greatly to our knowledge of the pathogenesis of tuberculosis. Throughout all of the above work, however, no one specific fact...

Lipoid proteinosis is a rare, autosomal recessive disorder that presents in early infancy with hoarseness, followed by pox-like and acneiform scars, along with infiltration and thickening of the skin and certain mucous membranes. Histological and ultrastructural examination reveals widespread deposition of hyaline-like material and disruption/reduplication of basement membrane around blood vess...

Stable isotope labelling of lipid precursors coupled with mass spectrometry-based lipidomic analyses and determination of isotope enrichment in substrate, intermediate and product pools provide the parameters needed to determine absolute flux rates through lipid pathways in vivo. Here, as an illustration of the power of such analyses we investigated lung phosphatidylcholine (PC) synthesis in Su...

Acknowledgements: M. Kutas (a Lady Davis fellow at Hebrew University) was supported from grants HD22614 and AG08313. We thank E. DeOchoa and T. Urbach for assistance.

Achia Urbach,1,2,4 Ori Bar-Nur,3,4 George Q. Daley,1,2,* and Nissim Benvenisty3,* 1Stem Cell Transplantation Program, Division of Pediatric Hematology/Oncology, Manton Center for Orphan Disease Research, Howard Hughes Medical Institute, Children’s Hospital Boston and Dana Farber Cancer Institute; Division of Hematology, Brigham and Women’s Hospital, Boston, MA 02115, USA 2Department of Biologic...

In earlier work, we showed that exponential (Urbach) band-edge states were localized on connected subnetworks of short bonds for the valence tail and long bonds for the conduction tail for high-quality continuous random network models of amorphous silicon. Here, we study size effects by computing the electronic density of states for a 105-atom model of α-Si proposed by G. T. Barkema and N. Mous...