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Background: Most new tuberculosis vaccines will be administered as a booster to subjects primed with bacille Calmette-Guérin (BCG) during childhood.Methods: We investigated in vivo and in vitro immune responses to mycobacteria in human immunodeficiency virus (HIV)-positive subjects in Tanzania primed with BCG during childhood and entering a tuberculosis booster vaccine trial. Tests included intradermal skin testing for Mycobacterium tuberculosis purified protein derivative (PPD) and Mycobacterium avium sensitin (MAS); lymphocyte proliferation assays and interferon (IFN)-gamma levels after stimulation with Mycobacterium vaccae sonicate (MVS), M. tuberculosis early secreted antigen (ESAT)-6, M. tuberculosis antigen 85 (Ag85), or M. tuberculosis whole-cell lysate (WCL); and determination of serum antibody to lipoarabinomannin (LAM).Results: A total of 888 subjects with CD4 cell counts > or = 200 cells/mm3 were enrolled. PPD and MAS test results were positive in 34% and 30% of the subjects, respectively. Proliferative responses were detected as follows: MVS, 6%; Ag85, 24%; ESAT-6, 21%; and WCL, 59%. IFN-gamma responses were 2%, 6%, 12%, and 38%, respectively. LAM antibody was detected in 28% of the subjects. Subjects were more likely to have detectable proliferative and IFN-gamma responses if they had positive PPD test results or CD4 cell counts > or = 500 cells/mm3. Overall, 94% of the subjects had evidence of primed mycobacterial immune responses.Conclusion: Of HIV-positive BCG-immunized adults with CD4 cell counts > or = 200 cells/mm3 in Tanzania, 94% are primed for booster mycobacterial immunization. [ABSTRACT FROM AUTHOR]

A fabric bending model that includes contributions from nonlinear elasticity, and viscous and Coulomb friction with hysteretic effects is presented. The model allows the recovery of the loading, unloading and hysteretis behaviors observed in the Kawabata evaluation system (KES) bending tests and provides the ability to simulate a continuum of property curves and to extrapolate to loading conditions not covered in the KES regimen. Model results are compared to experimental results. It is found that hysteretic behavior is observed due to friction between the yarns, and that nonlinear elastic behavior arises from jamming of the yarns and their subsequent compression. [ABSTRACT FROM AUTHOR]