Kinetic properties of the inhibition of juvenile hormone esterase by two trifluoromethylketones and O-ethyl,S-phenyl phosphoramidothioate     

Yehia A.I. Abdel-Aal  Richard M. Roe  Bruce D. Hammock 《Pesticide biochemistry and physiology》1984,21(2):232-241

Some inhibition kinetic properties and in vivo inhibition of the plasma juvenile hormone esterase from the cabbage looper (Trichoplusia ni Hübner) by one phosphoramidothioate and two trifluoromethylketones were examined. O-ethyl,S-phenyl phosphoramidothioate was shown to react irreversibly with the enzyme in a time-dependent manner, and the inhibition reaction can be factored into a reversible step with a dissociation constant, K_d, of 4.55 × 10^?5M followed by a phosphorylation step with a rate constant, k₂, of 1.98 min^?1. The phosphorylated enzyme did not show spontaneous recovery after 48 hr of dialysis. On the other hand, the two trifluoromethylketones were shown to act as reversible inhibitors, as their inhibited enzyme was regenerated completely after dialysis. However, 1,1,1,-trifluoro-3-thiooctylpropan-2-one, in contrast to 1,1,1-trifluorotetradecan-2-one, showed progressive time-dependent inhibition, and its reaction with the enzyme followed characteristic bimolecular second-order kinetics with a rate constant, k_i, of 3.37 × 10⁷M^?1 min^?1. The in vivo inhibition data of topically treated larvae at equimolar amounts of the tested compounds indicated rapid penetration, and the stability of the inhibition was higher for the phosphoramidothioate than for the trifluoromethylketones. The relationship of the mechanism of inhibition and the in vivo inhibition of these compounds to the understanding of the interactions between juvenile hormone and juvenile hormone esterase is discussed.  相似文献   

Attempts at Establishing Swine Herds Free from Atrophic Rhinitis and Virus Pneumonia: II. Repopulation with Specific Pathogen-Free Pigs *          下载免费PDF全文

T. J. L. Alexander  C. K. Roe 《The Canadian veterinary journal. La revue veterinaire canadienne》1962,3(10):299-306

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Effects of intraluminal glucose on intestinal secretion induced by heat stable and heat labile Escherichia coli enterotoxin, cholera toxin and theophylline.          下载免费PDF全文

D L Hamilton  M R Johnson  W E Roe    N O Nielsen 《Canadian journal of veterinary research》1978,42(1):89-96

Glucose, l-alanine, l-aspartate, l-methionine and glycine enhanced net fluid and electrolyte absorption in acute isolated loops of the proximal jejunum of weanling swine. The effect of glucose on intestinal secretion induced by heat stable and heat labile Escherichia coli entero-toxin, cholera toxin and theophylline was examined in both the proximal and distal jejunum of weanling swine. In the proximal jejunum glucose enhanced the rate of net fluid and electrolyte absorption. This increase was accompanied by an increase in unidirectional dosium absorption. In loops exposed to either heat stable or heat labile enterotoxins, glucose significantly decreased the rate of net fluid and electrolyte secretion. The magnitude of glucose enhancement in loops exposed to heat stable and heat labile enterotoxins was similar to adjacent control loops. However, glucose enhancement did not occur in loops exposed previously to cholera toxin or concurrently to theophylline. Therefore, cholera toxin and theophylline may inhibit substrate dependent sodium absorption in the proximal jejunum. In the distal jejunum glucose enhancement did occur but the rate of enhancement was less than in the proximal jejunum. In this region glucose enhancement was not evident in loops exposed to either theophylline, heat stable, heat labile or cholera toxin.  相似文献   

Problems of publishing     

Roe E 《Science (New York, N.Y.)》1981,212(4493):396

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Congenital polycystic kidney disease in lambs     

Johnstone AC  Davidson BI  Roe AR  Eccles MR  Jolly RD 《New Zealand veterinary journal》2005,53(5):307-314

AIM: To describe the pathology and inheritance of a congenital polycystic kidney disease (PKD) of sheep. METHODS: Mode of inheritance of PKD was investigated by evaluation of results of the disorder from planned matings in two consecutive years within subsets of a flock that had a high prevalence of PKD in lambs. Gross pathological and histopathological studies were based on tissues derived from this study. Haematoxylin and eosin (H&E)-stained paraffin sections of kidney, liver, extrahepatic biliary and pancreatic ducts, pancreas and epididymis were used to describe the lesions. RESULTS: Twenty-five lambs affected by PKD, of both sexes, were born, numbers in accord with those expected for an autosomal recessive disorder in the population studied. In all cases for which tissues were available, the renal, bile ductal (intrahepatic and extrahepatic), pancreatic and epididymal tissues had widespread dysplastic changes and associated cyst formation. CONCLUSIONS: The findings of renal cysts in conjunction with cysts in other organs are unifying features in many of the human and animal forms of PKD and suggest a related pathogenic and genetic base consistent with an autosomal recessive disorder.  相似文献   

Changes in scientific activities with age   总被引：1，自引：0，他引：1  

A Roe 《Science (New York, N.Y.)》1965,150(694):313-318

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A reply from the Pet Food Certification Committee          下载免费PDF全文

Brown GR  Roe CK 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(5):383

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Nonsense,fate, and policy analysis: The case of animal rights and experimentation     

Roe EM 《Agriculture and Human Values》1989,6(4):21-29

Animal rights and experimentation have become the focus of a major controversy in the United States, with acute implications for animal-related research in the laboratories and veterinary schools of many American universities. To date, efforts to reduce fundamental disagreements between animal researchers and animal welfare groups or to redefine their differences in ways that satisfy all concerned have by and large not been successful. In such situations where it is not possible to identify a middle ground between conflicting positions, the best a policy analyst may be able to do is to accentuate the issue's manifest topsy-turviness and uncertainties. No one can afford or risk having an issue of such high uncertainty, inconsistency, and stakes defined in terms so stark that they feel compelled to choose between those who say they know that the future shall hold us accountable for our wholesale slaughter of animals and those who would blame us for the human deaths they say will surely follow when we do not allow that slaughter.Emery Roe is a senior administrative analyst in the University of California's Office of Research and Public Policy and has a postdoctoral fellowship in resource economics at the University's Berkeley campus. He has published widely on agricultural, livestock, and environmental issues in the U.S. and Africa.  相似文献   

Detecting a leachate plume in an aeolian sand landscape using a DUALEM‐421 induction probe to measure electrical conductivity followed by inversion modelling     

J. Triantafilis  J. A. E. Roe  F. A. Monteiro Santos 《Soil Use and Management》2011,27(3):357-366

Solid waste poses a serious health risk when it is disposed of inadequately because water‐based solutions derived from the decomposition of solid waste products (leachate) can enter groundwater systems via plumes. To assess the public health risk and potential ecological impacts, we require knowledge on the pedological and hydrogeological settings in which waste is disposed. This is particularly the case in coarse textured highly permeable soil. To rapidly collect data, geophysical methods such as direct current (dc) resistivity techniques have been used. Moreover, non‐contact electromagnetic (EM) induction instruments have also been employed. The aim of this research was to demonstrate how the inversion using a 1‐dimensional inversion algorithm with lateral constraints of the apparent electrical conductivity (σ_a) measured in the horizontal coplanar (HCP) and perpendicular co‐planar arrays (PRP) of a DUALEM‐421 EM induction probe can be used to develop a two‐dimensional model of the true electrical conductivity (σ) within a Quaternary aeolian sand in the Tuggerah Soil Landscape southeast of Sydney in Australia. Our results from 2D models of σ accord with estimates of bulk electrical conductivity (σ_b) of a leachate plume and uncontaminated groundwater, the stratigraphy of the Tuggerah soil landscape unit and the depth of sand used to landscape the decommissioned landfill. Further research is needed to determine the origin of the plume and a quasi‐3D modelling approach is applicable.  相似文献   

A COLOR REACTION FOR DEHYDROASCORBIC ACID USEFUL IN THE DETERMINATION OF VITAMIN C     

Roe JH  Kuether CA 《Science (New York, N.Y.)》1942,95(2455):77

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