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191.
Katherine E. L. Worsley‐Tonks Elizabeth A. Miller Stanley D. Gehrt Shane C. McKenzie Dominic A. Travis Timothy J. Johnson Meggan E. Craft 《Zoonoses and public health》2020,67(4):460-466
The role of wildlife in the dissemination of antimicrobial‐resistant bacteria and antimicrobial resistance genes (ARGs) in the environment is of increasing concern. We investigated the occurrence, richness and transmissibility potential of ARGs detected in the faeces of three mesocarnivore species: the coyote (Canis latrans), raccoon (Procyon lotor) and Virginia opossum (Didelphis virginiana), and of stray and owned dogs in suburban Chicago, IL, USA. Rectal swabs were collected from live‐captured coyotes (n = 32), raccoons (n = 31) and Virginia opossums (n = 22). Fresh faecal samples were collected from locally owned (n = 13) and stray dogs (n = 18) and from the live‐captured mesocarnivores, when available. Faecal samples and rectal swabs were enriched to select for Enterobacteriaceae and pooled by mesocarnivore species and dog type (owned or stray). Pooled enriched samples were then analysed for the presence of ARGs using shotgun sequencing. The three mesocarnivore and stray dog samples had twice as many unique ARGs compared to the owned dog sample, which was partly driven by a greater richness of beta‐lactamase genes (genes conferring resistance to penicillins and cephalosporins). Raccoon and stray dog samples had the most ARGs in common, suggesting possible exposure to similar environmental sources of ARGs. In addition to identifying clinically relevant ARGs (e.g. blaCMY and qnrB), some ARGs were linked to the class 1 integrase gene, intI1, which may indicate anthropogenic origin. Findings from this pilot investigation suggest that the microbial communities of suburban mesocarnivores and stray dogs can host ARGs that can confer resistance to several antimicrobials used in human and veterinary medicine. 相似文献
192.
Luc Swevers Shane Denecke Kathrin Vogelsang Sven Geibel John Vontas 《Pest management science》2021,77(1):55-63
Mammalian intestinal organoids are multicellular structures that closely resemble the structure of the intestinal epithelium and can be generated in vitro from intestinal stem cells under appropriate culture conditions. This technology has transformed pharmaceutical research and drug development in human medicine. For the insect gut, no biotechnological platform equivalent to organoid cultures has been described yet. Comparison of the regulation of intestinal homeostasis and growth between insects and mammals has revealed significant similarities but also important differences. In contrast to mammals, the differentiation potential of available insect cell lines is limited and can not be exploited for in vitro permeability assays to measure the uptake of insecticides. The successful development of in vitro models could be a result of the emergence of molecular mechanisms of self‐organization and signaling in the intestine that are unique to mammals. It is nevertheless considered that the technology gap is a consequence of vast differences in knowledge, particularly with respect to culture conditions that maintain the differentation potential of insect midgut cells. From the viewpoint of pest control, advanced in vitro models of the insect midgut would be very desirable because of its key barrier function for orally ingested insecticides with hemolymphatic target and its role in insecticide resistance. © 2020 Society of Chemical Industry 相似文献
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人们通常认为流感只是一种仅持续数天的无害疾病 ,养鸡者对其的了解则比较充分。流感病毒的危害比一般人认为的都大 ,有些类型的流感病毒能够成为家畜乃至人类的杀手而会发生种间传播 相似文献
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197.
Kate E. Forster Andrew Wills Andrew M. Torrington Andy P. Moores David Thomson Gareth Arthurs Gordon Brown Hamish R. Denny Harry W. Scott Ian MacQueen James Dunne Jeremy Onyett John D. Walker John Prior Martin R. Owen Neil Burton Richard Whitelock Sarah Girling Shane Morrison Simon Gilbert Sorrel J. Langley‐Hobbs Toby J. Gemmill John F. Innes 《Veterinary surgery : VS》2012,41(5):545-550
198.
Rutherfurd SM Schneuwly A Moughan PJ 《Journal of agricultural and food chemistry》2007,55(20):8019-8024
Five feedstuffs were oxidized using performic acid, and these, along with their unoxidized counterparts, were acid hydrolyzed for multiple times (0-144 h) in degassed and vacuum-sealed glass tubes. The methionine sulfone, cysteic acid, methionine, and cysteine contents were determined for each hydrolysis time. Least-squares nonlinear regression of the sulfur amino acid contents and hydrolysis time was used to predict the actual sulfur amino acid content as well as the hydrolysis and loss rates. Least-squares nonlinear regression estimates for methionine content compared well with those of methionine sulfone for most of the feedstuffs tested. In contrast, the estimates for cysteine agreed poorly with cysteic acid. The loss rates during acid hydrolysis for methionine, methionine sulfone, and cysteic acid were low. Overall, acid hydrolysis in an evacuated sealed tube for 24 h without prior oxidation is suitable for methionine, but not cysteine, quantitation in some complex feedstuffs. 相似文献
199.
Fontaine J Zimmer U Moughan PJ Rutherfurd SM 《Journal of agricultural and food chemistry》2007,55(26):10737-10743
The suitability of the homoarginine reaction for determining the reactive lysine in soy products and corn distillers dried grain with solubles (DDGS) was tested. For this purpose, some batches were subjected to deliberate heat damage for up to 30 min in an autoclave with 135 degrees C hot steam, and the samples were analyzed for total lysine and reactive lysine. In addition, 84 samples of common soy and 80 samples of corn DDGS were tested for their content of total and reactive lysine, and the contents were compared with those of the autoclave tests. For soy products conclusive results were obtained. In the case of heat treatment, both total lysine and reactive lysine decrease, but the latter is clearly a more sensitive indicator of lysine damage. Most normal products are quite similar, with toasting-induced damage to reactive lysine of ca. 15% compared to untoasted beans. The cause of the constantly occurring residual lysine after guanidination and the poorer reaction balance in the case of damage were explained. For common DDGS samples, however, less favorable results were obtained. Reactive and total lysine decreased almost in parallel due to heat damage, showing a great gap between them. Results showed indeed that variation of total and reactive lysine in DDGS is high, proving that its production conditions are not yet optimal for a feed ingredient. 相似文献
200.
BACKGROUND: Wild radish, a problem weed worldwide, is a severe dicotyledonous weed in crops. In Australia, sustained reliance on ALS‐inhibiting herbicides to control this species has led to the evolution of many resistant populations endowed by any of several ALS mutations. The molecular basis of ALS‐inhibiting herbicide resistance in a novel resistant population was studied. RESULTS: ALS gene sequencing revealed a previously unreported substitution of Tyr for Ala at amino acid position 122 in resistant individuals of a wild radish population (WARR30). A purified subpopulation individually homozygous for the Ala‐122‐Tyr mutation was generated and characterised in terms of its response to the different chemical classes of ALS‐inhibiting herbicides. Whole‐plant dose‐response studies showed that the purified subpopulation was highly resistant to chlorsulfuron, metosulam and imazamox, with LD50 or GR50 R/S ratio of > 1024, > 512 and > 137 respectively. The resistance to imazypyr was found to be relatively moderate (but still substantial), with LD50 and GR50 R/S ratios of > 16 and > 7.8 respectively. In vitro ALS activity assays showed that Ala‐122‐Tyr ALS was highly resistant to all tested ALS‐inhibiting herbicides. CONCLUSION: The molecular basis of ALS‐inhibiting herbicide resistance in wild radish population WARR30 was identified to be due to an Ala‐122‐Tyr mutation in the ALS gene. This is the first report of an amino acid substitution at Ala‐122 in the plant ALS that confers high‐level and broad‐spectrum resistance to ALS‐inhibiting herbicides, a remarkable contrast to the known mutation Ala‐122‐Thr endowing resistance to imidazolinone herbicide. Copyright © 2012 Society of Chemical Industry 相似文献