Species composition of mosquitoes collected in the Murray Valley of South-eastern Australia during an epidemic of arboviral encephalitis

Mosquito activity at the height of an epidemic of arboviral encephalitis in the Murray Valley during the summer of 1974 was almost entirely crepuscular and nocturnal, but anecdotal evidence, indicated that day-biting Aedes species were also unusually prevalent during the first 4-5 weeks of the epidemic. Ninety-eight percent of the 138,359 mosquitoes captured in miniature light traps and by aspiration between 4th and 13th February, 1974, were Culex annulirostris, and 10 other species of 5 genera comprised the remaining 2%. In the one 'man-biting' collection 96% of 1,364 mosquitoes were Cx annulirostris. The overall capture rate for 51 light trap nights at 7 widely dispersed collecting sites was 2,675. At Barmah Forest 10 light trap nights yielded an average of 9,103 mosquitoes, with a maximum of 26,293 in one trap night.

Further observations on the activation of lysosomal acid alpha-glucosidase by cortisone derivatives

1. Cortisone acetate activates the acid alpha-glucosidase in rat liver slices and in isolated liver lysosomes. 2. The reaction is steroid specific and moreover does not occur with lysosomal acid phosphatase or beta-galactosidase. 3. After pretreatment of the lysosomes with cortisone, substrate (maltose) binding to the soluble lysosomal acid alpha-glucosidase is not affected, but the steroid does increase the V(max.) value. Membrane-bound enzyme is not activated by cortisone. 4. 4-[(14)C]Cortisone is preferentially bound to the lysosomal membrane and the possible involvement of this structure in the activation phenomenon is discussed.

Studies on type II glycogenosis. Effects of cortisone derivatives on acid -glucosidase

Cortisone causes a marked increase in the activity of liver acid alpha-glucosidase 2h after injection into male Wistar rats. Studies on rat liver tissue slices, isolated lysosomes and cultured skin fibroblasts have demonstrated similar elevations of acid alpha-glucosidase activity after incubation with cortisone. Cortisone-treated human liver tissue, obtained by needle biopsy, also shows an increase in acid alpha-glucosidase activity. Neutral alpha-glucosidase activity was not stimulated by cortisone in vivo or in liver slices.