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681.
Beverley A. Holloway 《New Zealand journal of zoology.》2013,40(4):279-301
Mystacinobia zelandica n.sp. is described. It is the sole member of Mystacinobia new genus and of Mystacinobiidae new family, and belongs to the superfamily Drosophiloidea. The species lives in large communities in roosts of the New Zealand short‐tailed bat, Mystacina tuberculata, and requires temperatures around 30°c for development and survival. Adults are physogastric, apterous, and have reduced eyes. The claws are adapted for movement over bat fur, but the mouthparts are not modified for blood‐feeding. Adults and larvae feed on guano. Eggs are laid in clusters in roost wood, and have non‐functional respiratory horns. Larvae have elongate anterior spiracles, tubular posterior spiracles, and 5 pairs of anal papillae. The puparium has a reduced operculum. Dispersal to new roosts depends entirely on transport by Mystacina, and as many as 10 phoretic flies have been found embedded in fur of individual bats leaving a roost to feed at night. The species has reached a degree of sociality which includes group oviposition, partial overlapping of generations, clustering of all stages, mutual grooming, male polymorphism, and extension of the males’ life‐span beyond the reproductive phase to form a sound‐producing guard caste which probably prevents the bats from interfering with the bat‐fly community. Mystacinobia zelandica is part of the New Zealand Endemic (Archaic) Element, which also includes Mystacina tuberculata. 相似文献
682.
T. N. C. Mangwiro S. J. Torr J. R. Cox M. T. P. Holloway 《Medical and veterinary entomology》1999,13(3):315-323
The efficacy of various pyrethroid insecticides for use on odour-baited targets to control tsetse was compared in Zimbabwe. Formulations were applied to cotton cloth and polyester net and, at various intervals, the materials were bioassayed by exposing fed female Glossina pallidipes (Austen) (Diptera: Glossinidae) to cloth for 45 s or by inducing them to collide briefly with net. Trial formulations were compared with deltamethrin suspension concentrate (s.c.), the insecticide currently used in tsetse control operations in Zimbabwe. Applying 0.8% suspension of alphacypermethrin to cloth or net produced high mortalities for 9 months which was similar in performance to 0.4% suspension of deltamethrin s.c. Deltamethrin s.c. and beta-cyfluthrin s.c. applied to cloth as 0.1% suspensions were equally effective, producing high mortalities for 2 months during the wet season, and 0.8% suspension of beta-cyfluthrin was effective for 12 months. Suspensions of 0.1% lambdacyhalothrin capsule suspension or 0.1% lambdacyhalothrin wettable powder were significantly less effective than 0.1% deltamethrin s.c. Chemical analyses showed that increasing the concentration of insecticide applied to material increased the initial amount of insecticide on the material and decreased the subsequent rate of loss; 0.1% suspension of beta-cyfluthrin s.c. applied to cloth produced an initial concentration of approximately 280 mg/m2 which declined by 94% in 12 months whereas 0.8% suspension showed no significant decrease in concentration (mean= 1304 mg/m2) over the same period. For controlling tsetse by means of pyrethroid-treated targets, it is suggested that beta-cyfluthrin s.c. is as effective as deltamethrin s.c. but that alphacypermethrin s.c. should be used at twice the concentration of deltamethrin s.c. to obtain the same performance. 相似文献
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High-level expression of three members of the murine angiogenin family in Escherichia coli and purification of the recombinant proteins. 总被引:2,自引:0,他引:2
D E Holloway M C Hares R Shapiro V Subramanian K R Acharya 《Protein expression and purification》2001,22(2):307-317
Angiogenin (Ang) is a small basic protein which belongs to the pancreatic ribonuclease superfamily. It potently induces the formation of new blood vessels and has emerged as a promising anticancer target. Mice possess genes encoding one ortholog (mAng) and three homologs of Ang, designated angiogenin-related protein (mAngrp), angiogenin-3 (mAng-3), and angiogenin-4 (mAng-4). Structural and functional study of these homologs has been hampered by the low yield of protein from the existing heterologous expression system. In the experiments described, we used a pET expression vector to express these proteins in the cytoplasm of Escherichia coli BL21-CodonPlus(DE3)-RIL cells, whereupon substantial amounts of each accumulated in the form of insoluble aggregates. The proteins were renatured using an arginine-assisted procedure and subsequently purified by cation-exchange chromatography and reversed-phase HPLC; each purified protein was shown to be enzymatically active toward tRNA. The yields of pure mAngrp and mAng-3 were 7.6 and 12 mg/liter culture, respectively, representing substantial increases over previously reported experiments. This is also the first report of the expression and purification of mAng-4, obtained here in a yield of 30 mg/liter culture. The ready availability of milligram quantities of these proteins will enable further functional studies and high-resolution structural analyses to be conducted. 相似文献
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A new technique for single-step subcellular fractionation of adipose tissue homogenates by analytical sucrose density gradient centrifugation in a vertical pocket reorientating rotor is described. The density gradient distributions of mitochondrial and peroxisomal marker enzymes in brown and white adipose tissue of control and cold exposed rats are compared. The equilibrium density of brown fat mitochondria was found to be significantly increased compared with white fat mitochondria. GDP binding activity was localized solely to the mitochondria in both control and cold-adapted brown adipose tissue. Brown and white fat mitochondria fractions were isolated by differential centrifugation and the specific activities of various enzymes in the homogenate and mitochondrial preparations determined. The specific activity of creatine kinase in brown adipose tissue was found to be ten-fold higher than in white fat and subcellular fractionation studies showed the activity to have an exclusively cytosolic distribution in both tissues. GDP binding activity and some of the mitochondrial enzymes showed, in brown adipose, a striking increase in total activity in cold adapted rats compared to control animals. For some enzyme activities there was a small increase when expressed per mg tissue or per mg mitochondrial protein. When expressed per mg DNA i.e. per cell, there was a reduced specific activity of the mitochondrial and peroxisomal enzymes in both brown and white adipose tissue on cold adaptation. 相似文献
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