Candida glabrata is an emerging opportunist pathogen in immunosuppressed patients. C. glabrata is resistant to many antifungal agents and until recently, there have been no standard treatment regimens for this organism. A mouse model was established using mice immunosuppressed with 5 fluorouracil to evaluate amphotericin B, flucytosine, fluconazole and their combinations to treat an intravenously induced C. glabrata infection. Treatment with fluconazole, flucytosine, amphotericin B or a combination was begun one day after infection. Following 5 days of treatment, the mice were killed for fungal counts in kidneys and spleen. At the doses used, amphotericin B was superior to fluconazole or flucytosine alone in the treatment of C. glabrata infections. Flucytosine reduced the fungal burden in the kidney for only two of four isolates of C. glabrata. The combination of fluconazole and flucytosine was superior to these agents alone in reducing the tissue burden in the kidney for one isolate of C. glabrata. High doses of fluconazole alone produced modest reductions in kidney counts but did not reduce spleen tissue counts. There was poor correlation between in-vitro MICs and in-vivo results.

Irradiation by pulsed microwaves (9.4 GHz, 1 microsecond pulses at 1,000/s), both with and without concurrent amplitude modulation (AM) by a sinusoid at discrete frequencies between 14 and 41 MHz, was assessed for effects on the immune system of Balb/C mice. The mice were immunized either by sheep red blood cells (SRBC) or by glutaric-anhydride conjugated bovine serum albumin (GA-BSA), then exposed to the microwaves at a low rms power density (30 microW/cm2; whole-body-averaged SAR approximately 0.015 W/kg). Sham exposure or microwave irradiation took place during each of five contiguous days, 10 h/day. The antibody response was evaluated by the plaque-forming cell assay (SRBC experiment) or by the titration of IgM and IgG antibodies (GA-BSA experiment). In the absence of AM, the pulsed field did not greatly alter immune responsiveness. In contrast, exposure to the field under the combined-modulation condition resulted in significant, AM-frequency-dependent augmentation or weakening of immune responses.

No abstract

Natural Killer cell activity and antibody response were studied in Balb/c mice which were exposed in vivo to uniform pulsed magnetic fields (square-wave, 0.8 Hz, 120 mT maximum field strength, 0.1 s rise-time) for 5 days, 10 h/day. No effects were found in antibody response to sheep red blood cell (SRBC) immunization as assayed by counting the plaque-forming cells (PFC) in the spleens of animals on the sixth day. Following 5-day exposures, the activity of Natural Killer (NK) cells was measured in vitro by challenge with YAC-1 cells, in experiments in which mice were not immunized. An increase of NK cytotoxic activity due to exposure was found which depended on the age of the mice (effect observed above 12 weeks) and on the strength of the applied field (effect observed above 30 mT).

Major polypeptide species of proteins have been identified and analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis in fresh extracts of the whole leaf, leaf gel, root and stalk portions of Aloe barbudensis Miller plants of immature, young and mature ages. Extracts of the fresh Aloe plant portions were prepared by dissection, tissue disruption, differential centrifugation and gel filtration methods. Extracted plant portions analysed by separation electrophoresis were also assayed by biochemical and immunological techniques for the presence of lectin associated reactions, i.e. agglutination or mitogenicity. Results of the separation electrophoresis analysis of extracts prepared from fresh whole leaves and leaf gel of mature Aloe barbadensis Miller plants revealed 23 identifiable difterent polypeptides. Molecular weights of these polypeptides, calculated from sets of molecular weight reference standards, ranged from 70000 for the largest to 3OOO for the smallest. Electrophoresis profiles of commercially processed and freshly processed Aloe barbadensis Miller and Aloe suponaria Haw leaf gel extracts revealed similar patterns for major peptides. Treatment of mature whole Aloe leaf extracts with acidic and alkaline conditions revealed distinct changes in pH stability of ten peptides. Comparisons of separation electrophoresis profiles of fresh extracts of Aloe whole leaves and of leaf gel portions revealed marked differences in both molecular weights and concentrations of peptides found in extracts from mature, young or immature plants. This report is the first to describe the nature and types of polypeptides detected in extracts of whole leaf, leaf gel, stalk and root portions of immature, young and mature Aloe plants. Accordingly, information in this report may be of considerable value in helping to identify and characterize Aloe substances present during processing in extracts and in products.