Group B streptococcus can be a serious infection of neonates and, in the past, specific antibody has been shown to mediate immunity against this organism. However, specific antibody is not required for phagocytosis of highly pathogenic organisms by neutrophils. Furthermore, the bacteria subsequently survive and tend to accumulate or multiply in these cells, which they then disrupt. Highly pathogenic streptococci are killed by neutrophils in the presence of specific antibody. Moreover, the addition of specific antibody to neutrophils after phagocytosis of the organisms had occurred stimulated the phagocytes to kill the ingested bacteria. This post-phagocytic role for antibody in the killing of bacteria by neutrophils, as opposed to their ingestion, has not been previously described. Once inside the cell, specific antibody binds to protective surface determinants on the bacteria and allows the organisms to be killed. Present work involves an examination of the surface virulence determinants that are responsible for the survival of highly pathogenic group B streptococci within neutrophils. Adsorption of fibronectin to Teflon followed by S.aureus adherenceInfection of implanted prostheses or catheters represent a major problem in modern medicine. We have recently demonstrated that fibronectin (FN) is an important ligand of Staphylococcus aureus adherence to polymethylmethacrylate (PMMA) material, which was implanted into animals and used as an experimental model of foreign body infection (J. infect. Dis. 150, 546). In a related in vitro study, we described FN adsorption by PMMA coverslips (J. infect. Dis. 45, 768). Using similar techniques, we studied quantitative adsorption of 125I-labeled FN and promotion of S. aureus adherence onto Teflon | which is a widely used material in the clinic. The adsorption of purified FN for Teflon was dose-dependent and resembled that for PMMA. Promotion of S. aureus adherence by Teflon | adsorbed FN was dose-dependent, leading to increased bacterial adherence up to a maximum of 6.5 x 104 bacteria per coverslip. In contrast, Teflon unexposed to FN bound 3 • 103 bacteria by coverslip. FN adsorption on Teflon | and its promotion of bacterial adherence were prevented by other serum proteins ( = FN-depleted serum pool). In summary, FN adsorption and its promotion of S. aureus adherence by Teflon are similar to those found previously with PMMA.A prospective study of urinary tract infections in long-term catheterized spinal injury patients revealed their complexity. Mixed bacterial communities of up to eight multi-drug resistant species were commonly isolated. In the absence of chemotherapy some species were persistent and others transient inhabitants. In vitro, tests showed that there was no correlation between adherence of the bacteria to bladder uroepithelial cells and persistence. Pseudomonas aeruginosa gave significantly higher adherence to silicone-and teflon-coated catheter sections than all the other isolates. Overall however there was no relationship between persistence and the abi...

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Two radiochemical methods for the quantitative determination of tantalum and niobium, with the aid of 182Ta and 95Nb, are described. If only one of these radio‐isotopes is present, it can be determined by counting the gamma radiation emitted in a well‐cristal scintillator. The simultaneous determination of both Ta and Nb is possible by the interpretation of the entire spectrum obtained in the presence of both radioisotopes.

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