Quantitative I-123-IMP brain SPECT and neuropsychological testing in AIDS dementia.

We performed I-123-IMP SPECT brain imaging on seven mildly demented AIDS patients and seven normal subjects. In an attempt to detect and quantitate regions of decreased I-123-IMP uptake, pixel intensity histograms of normalized SPECT images at the basal ganglia level were analyzed for the fraction of pixels in the lowest quartile of the intensity range. This fraction (F) averaged 17.5% (S.D. = 4.6) in the AIDS group and 12.6% (S.D. = 5.1) in the normal group (p less than .05). Six of the AIDS patients underwent neuropsychological testing (NPT). NPT showed the patients to have a variety of mild abnormalities. Regression analysis of NPT scores versus F yielded a correlation coefficient of .80 (p less than .05). We conclude that analysis of I-123-IMP SPECT image pixel intensity distribution is potentially sensitive in detecting abnormalities associated with AIDS dementia and may correlate with the severity of dementia as measured by NPT.

Application phenomena and efficacy of concentrated acaricide dusts for northern fowl mite control on caged laying hens.

Fluorescent pigments were used to measure plumage coverage when caged laying hens were dusted for northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), control. Carriage type electrostatic or high velocity backpack equipment produced superior coverage 2 hr posttreatment when the rates of 454 g (1 lb) dust per 100 or 500 hens was employed. A redistribution of dust was noted 48 hr posttreatment, and a subsequent experiment demonstrated that this phenomenon resulted from intracage cross contamination dependent upon bird caging density. Carbaryl 80% wettable powder (WP) at 454 g/1600 hens and tetrachlorvinphos 50% WP at 454 g/1000 hens provided northern fowl mite control for 11 and 5 weeks posttreatment, respectively.

Comparative evaluation of four registered acaricides for field control of northern fowl mites on caged laying hens.

Carbaryl and tetrachlorvinphos provided longer lasting control of northern fowl mites, Ornithonyssus sylviarum (Canestrini and Fanzago), than did coumaphos or malathion when the materials were applied to caged laying hens as aqueous sprays. The average duration of residual control was ca. 5 weeks for carbaryl, 4.3 weeks for tetrachlorvinphos, 3.5 weeks for coumaphos, and 2 weeks for malathion. No presumptive evidence of northern fowl mite resistance to carbaryl or tetrachlorvinphos was encountered. In contrast, malathion often failed to produce satisfactory control, and difficulty with adequate dispersion of coumaphos wettable powder was noted.