Several cationic peptides that were isolated from rabbit granulocytes exerted fungicidal activity against arthroconidia of Coccidioides immitis in vitro. The fungicidal effect of the cationic peptides required at least 4-8 hr of contact between peptide and fungal cells and appeared to be dependent upon active fungal metabolism. The fungicidal activity was inhibited by increases in the tonicity of the growth medium but was not inhibited by changes in pH. These findings provide a potential mechanism whereby phagocytic cells may limit the spread of infection due to C. immitis.

Experiments were carried out to test the validity of the hypothesis that postulated differences in the nature of the antigen receptors of primary and secondary B cells should be reflected in a greater specificity in primary B-cell stimulation (2). Enumeration of clonal precursors stimulated by either DNP-Hy, TNP-Hy, or a mixture of both antigens confirmed this hypothesis. Since the sum of primary B cells stimulated by DNP-Hy and TNP-Hy is approximately equal to the number stimulated by a mixture of both, overlap stimulation of primary B cells by these antigens could be considered negligible. In contrast, the stimulation of B cells from mice previously immunized with DNP-Hy showed extensive overlap of stimulation by DNP-Hy and TNP-Hy. Thus secondary B cells appear less fastidious in their affinity requirements for stimulation than primary B cells.

Immunohistochemical techniques using monoclonal antibodies to T lymphocyte subpopulations were used to characterize further the granulomas of disseminated coccidioidomycosis. Skin biopsy specimens from patients with disseminated coccidioidomycosis were studied and compared with tissues from experimentally infected mice. In human skin biopsy specimens and infected mouse tissues, discrete granulomata were seen in which T lymphocytes formed a peripheral mantle surrounding central aggregates of macrophages. This unusual pattern of granuloma formation may represent an ineffective host response because these individuals are unable to clear their infection. Because of the close similarity of immunopathology in both human and mouse infections, the mouse model should serve as a useful tool in elucidating the factors contributing to ineffective host responses in systemic fungal infections.

No abstract

The Evolutionary Map of the Universe (EMU) large-area radio continuum survey will detect tens of millions of radio galaxies, giving an opportunity for the detection of previously unknown classes of objects. To maximise the scientific value and make new discoveries, the analysis of this data will need to go beyond simple visual inspection. We propose the coarsegrained complexity, a simple scalar quantity relating to the minimum description length of an image, that can be used to identify images that contain complex and unusual structures. The complexity can be computed without reference to the ensemble or existing catalogue data, making the computation efficient on surveys at very large scales (such as the full EMU survey). We apply our coarse-grained complexity measure to data from the EMU Pilot Survey to detect and confirm anomalous objects in this data set and produce an anomaly catalogue. Rather than work with existing catalogue data using a specific source detection algorithm, we perform a blind scan of the area, computing the complexity using a sliding square aperture. The effectiveness of the complexity measure for identifying anomalous objects is evaluated using crowd-sourced labels generated via the Zooniverse.org platform. We find that the complexity scan captures unusual sources, such as odd radio circles, in the high-value tail of the complexity distribution. We use this distribution to produce catalogues of the 5%, 1% and 0.5% most complex frames with the largest catalogue estimated to be 86% complete and the smallest catalogue 94% pure.