Avian Health across the Landscape: Nestling Immunity Covaries with Changing Landcover.

The landscape composition of an organism's home range or territory should influence aspects of its condition, including measures of immune function. Changes in immunocompetence arising from variation in landcover may provide important links between habitat changes and patterns of disease spread. To establish a baseline understanding for whether immune measures covary with changes in landcover, we examined associations between immunological parameters and landcover composition for adults and nestlings of five shrubland bird species. Specifically, we examined the bacteria-killing ability (BKA) of the blood plasma and profiles of the five avian leukocytes as our measures of immune function, and assessed the proportion of area around each bird's nest that was composed of the four major landcover types in the Midwestern USA: row crop agriculture, developed, forest, and grass/shrub. We performed landcover assessments at 100 and 1000 m radius buffers to identify whether associations between habitat and immune function differed at the two spatial scales. As part of this work, we examined age and species-related immunological variation, as well as associations among the immune parameters. There was little evidence linking variation in immune function to landcover composition for the adults at either spatial scale, but there were numerous associations for nestlings, and these were stronger at the 1000 than 100 m spatial scale. The proportion of grass/shrub around the nest had the largest impact on immune function, although the effect varied by immune parameter and species. BKA and basophils were inversely associated with grass/shrub for all species, whereas lymphocytes were positively associated with grass/shrub for all species. We also documented species-level differences among adults and nestlings for BKA and all leukocytes except monocytes. As expected, we found that nestlings had reduced levels of BKA, lymphocytes, monocytes, and elevated heterophils compared with adults (except for field sparrow-Spizella pusilla-nestlings, which had higher lymphocytes). Basophils generally did not differ by age class, and eosinophils exhibited species-specific patterns, in which they were higher for nestling American robins (Turdus migratorius) and gray catbirds (Dumetella carolinensis) compared with adults, but lower in the other nestlings. Heterophils and lymphocytes were inversely associated for all species and age classes, and basophil levels were positively associated with BKA across species and age classes. Together, these findings bolster our understanding of age and species-specific variation in immune function, and provide evidence that immune measures can covary with changes in landcover.

Double-blind study of pulsing magnetic field effects on multiple sclerosis.

We performed a double-blind study to measure the clinical and subclinical effects of an alternative medicine magnetic device on disease activity in multiple sclerosis (MS). The MS patients were exposed to a magnetic pulsing device (Enermed) where the frequency of the magnetic pulse was in the 4-13 Hz range (50-100 milliGauss). A total of 30 MS patients wore the device on preselected sites between 10 and 24 hours a day for 2 months. Half of the patients (15) randomly received an Enermed device that was magnetically inactive and the other half received an active device. Each MS patient received a set of tests to evaluate MS disease status before and after wearing the Enermed device. The tests included (1) a clinical rating (Kurtzke, EDSS), (2) patient-reported performance scales, and (3) quantitative electroencephalography (QEEG) during a language task. Although there was no significant change between pretreatment and posttreatment in the EDSS scale, there was a significant improvement in the performance scale (PS) combined rating for bladder control, cognitive function, fatigue level, mobility, spasticity, and vision (active group -3.83 +/- 1.08, p < 0.005; placebo group -0.17 +/- 1.07, change in PS scale). There was also a significant change between pretreatment and posttreatment in alpha EEG magnitude during the language task recorded at various electrode sites on the left side. In this double-blind, placebo-controlled study, we have demonstrated a statistically significant effect of the Enermed magnetic pulsing device on patient performance scales and on alpha EEG magnitude during a language task.