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51.
单克隆抗体检测栗疫菌dsRNA的研究初报 总被引:4,自引:0,他引:4
本文利用dsRNA特异性单克隆抗体,采用双抗体夹芯ELISA法,检测了栗疫菌中的dsRNA.结果表明,该法不仅能从栗疫菌低毒力菌株的总核酸粗提液中检测到dsRNA而不受其它核酸的干扰,而且比电泳法简便迅速,在大量筛选含dsRNA的栗疫菌低毒力菌株中具有很大的实用价值。 相似文献
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Intact spinach chloroplasts were used to determine if clomazone, 5-OH clomazone, and/or 5-keto clomazone inhibited the chloroplastic isoprenoid pathway. When isopentenyl pyrophosphate was used as a precursor, neither clomazone nor the clomazone metabolites (5-OH clomazone and 5-keto clomazone) inhibited the formation of products separated by HPLC in the organic phase. However, when pyruvate, a substrate for the first committed step of the pathway, was used as a precursor, both 5-keto clomazone and fosmidomycin reduced the formation of a non-polar product and increased the formation of a polar product in the organic phase. Only 5-keto clomazone, not 5-OH clomazone or clomazone, inhibited the formation of an additional product other than fosmidomycin in the aqueous phase from pyruvate incorporation. In an in vitro assay, 5-keto clomazone inhibited DXP synthase, the enzyme catalyzing the first committed step of the chloroplastic isoprenoid pathway. Therefore, our studies show that neither clomazone nor 5-OH clomazone inhibits the chloroplastic isoprenoid pathway, only 5-keto clomazone does. 相似文献
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Laura Jesse Michael Collyer Kirk Moloney John J. Obrycki 《Weed Biology and Management》2013,13(3):79-88
Rosa multiflora Thunb. (Rosaceae), an invasive plant that currently infests millions of hectares in the eastern half of the USA, was planted initially in the 1940s as a “living fence”, cover for game animals and for erosion control. The larvae of Megastigmus aculeatus var. nigroflavus Hoffmeyer (Hymenoptera: Torymidae) feed on the developing R. multiflora seeds and have the potential to reduce the seed output of R. multiflora. Rosehips were collected from 49 sites across eastern and southern Iowa, USA, to determine the presence and distribution of M. aculeatus, the larvae of which were found in 266 of the 979 (27%) rosehips that were dissected and at 31 of the 49 sites (63%) that were sampled. The levels of M. aculeatus infestation over 2–3 years were determined at three selected sites and it was documented that more seeds were aborted than were viable or contained wasp larvae. A negative relationship was observed between the numbers of both the aborted and the viable seeds and the probability of a rosehip being attacked by M. aculeatus, indicating that M. aculeatus females are not preferentially selecting rosehips with higher numbers of viable or aborted seeds for oviposition. There is a significant reduction in both the viable seeds and the aborted seeds in hips that have been attacked by M. aculeatus. Detailed knowledge of R. multiflora demography is necessary to determine the level of seed predation that is required to reduce the recruitment of new individuals into the population. 相似文献
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Waseem Akbar Anilkumar Gowda Jeffrey E Ahrens Jason W Stelzer Robert S Brown Scott L Bollman John T Greenplate Jeffrey Gore Angus L Catchot Gus Lorenz Scott D Stewart David L Kerns Jeremy K Greene Michael D Toews David A Herbert Dominic D Reisig Gregory A Sword Peter C Ellsworth Larry D Godfrey Thomas L Clark 《Pest management science》2019,75(3):867-877
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ABSTRACTPest management professionals in California receive more customer complaints about Argentine ants than for any other urban ant pest. Fipronil, applied as a 30 × 30 cm band around the house foundation, has become the preferred treatment used to control these ants. Unfortunately, fipronil is now showing up in urban waterways at levels that are toxic to aquatic invertebrates. Our recent studies are aimed at mitigating insecticide runoff while still controlling the ant infestations. A high priority is preventing fipronil runoff from the driveway to the street, where it can flow into drains and from there to urban waterways. In this paper, two related studies address these issues. Not treating driveways with fipronil reduced by two to three orders of magnitude its runoff when compared with earlier studies. However, not treating the driveway can reduce efficacy of treatments. Granular bifenthrin, indoxacarb, botanicals, and a thiamethoxam ant bait were tested as supplemental treatments. The gel bait showed the best result as a supplement, but only after 8 weeks. We have reduced fipronil runoff while maintaining efficacy of the ant treatments. 相似文献
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Salman Ahmed Waqas Alam Philippe Jeandet Michael Aschner Khalaf F. Alsharif Luciano Saso Haroon Khan 《Marine drugs》2022,20(8)
Prostate cancer (PCa) is the leading cause of cancer death in men, and its treatment is commonly associated with severe adverse effects. Thus, new treatment modalities are required. In this context, natural compounds have been widely explored for their anti-PCa properties. Aquatic organisms contain numerous potential medications. Anticancer peptides are less toxic to normal cells and provide an efficacious treatment approach via multiple mechanisms, including altered cell viability, apoptosis, cell migration/invasion, suppression of angiogenesis and microtubule balance disturbances. This review sheds light on marine peptides as efficacious and safe therapeutic agents for PCa. 相似文献
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Francesco Margiotta Laura Micheli Clara Ciampi Carla Ghelardini J. Michael McIntosh Lorenzo Di Cesare Mannelli 《Marine drugs》2022,20(12)
Conus regius is a marine venomous mollusk of the Conus genus that captures its prey by injecting a rich cocktail of bioactive disulfide bond rich peptides called conotoxins. These peptides selectively target a broad range of ion channels, membrane receptors, transporters, and enzymes, making them valuable pharmacological tools and potential drug leads. C. regius-derived conotoxins are particularly attractive due to their marked potency and selectivity against specific nicotinic acetylcholine receptor subtypes, whose signalling is involved in pain, cognitive disorders, drug addiction, and cancer. However, the species-specific differences in sensitivity and the low stability and bioavailability of these conotoxins limit their clinical development as novel therapeutic agents for these disorders. Here, we give an overview of the main pharmacological features of the C. regius-derived conotoxins described so far, focusing on the molecular mechanisms underlying their potential therapeutic effects. Additionally, we describe adoptable chemical engineering solutions to improve their pharmacological properties for future potential clinical translation. 相似文献