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The present study describes efficient and facile syntheses of varyingly substituted 3-thioaurones from the corresponding 3-oxoaurones using Lawesson’s reagent and phosphorous pentasulfide. In comparison, the latter methodology was proved more convenient, giving higher yields and required short and simple methodology. The structures of synthetic compounds were unambiguously elucidated by IR, MS and NMR spectroscopy. All synthetic compounds were screened for their inhibitory potential against in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Molecular docking studies were also performed in order to examine their binding interactions with AChE and BChE human proteins. Both studies revealed that some of these compounds were found to be good inhibitors against AChE and BChE.  相似文献   
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This study aims to investigate the role of Paenibacillus terrae AY-38 to produce bioactive metabolites and to counteract pathogenic infections caused by B. cinerea. The pure culture of P. terrae (AY-38) showed the secretion of significant amount of IAA (indole-3-acetic acid) (109.57?±?3.2?µg?mL?1). The AY-38 strain also produced siderophore and glucanase, while in the in vitro test, it showed significant antagonism to Botrytis cinerea. In the in vivo plant experiment, the sole application of AY-38 significantly improved plant growth (plant height and leaf area), while in B. cinerea infected plants, AY-38 inoculation not only decreased the disease incidence on leaves and fruits but also reprogramed the plants for higher growth. AY-38 treatments promoted and rescued plant growth by modulating the defence responses of endogenous hormones, such as jasmonic and salicylic acids. Our findings concluded that P. terrae possesses great potential as a possible biocontrol agent against B. cinerea-induced pathogenic infections.  相似文献   
54.
The objective of the present study was to determine the potential plant growth-promoting action of bacterial endophytes isolated from arid land-dwelling plants under normal conditions. Overall, five bacterial endophytes LK11 (Sphingomonas sp. LK11), TP5 (Bacillus subtilis), MPB5.3 (B. subtilis subsp. Subtilis), S9 (B. subtilis subsp. Subtilis), and TP1 (Serratia marcescens) were evaluated based on morphological characteristics after isolation and purification. Phytohormonal analysis of these endophytes predicted indole acetic acid (IAA) production 12.31?±?0.45?, 6.8?±?0.59, and 10.5?±?1.02?μM/mL in the culture broths of LK11, MPB5.3, and TP1, respectively. Under controlled greenhouse conditions, these endophytes were inoculated into soybean, and their growth-promoting characteristics were compared with those of non-phytohormone-producing endophytes. In terms of plant growth promotion, among IAA-producing endophytes, LK11 and TP1 greatly improved physiological characteristics such as shoot/root length, fresh/dry weight, and chlorophyll contents. However, the non-phytohormone-producing endophytes TP5 and S9 did not show a growth-promoting effect. Based on these results, plants inoculated with LK11 and TP1 along with a control were subjected to endogenous hormonal analysis and showed a significant increase in abscisic acid (457.30–398.55 vs. 205.93 ng/g D.W.) and a decrease in jasmonic acid content (50.07–85.07 vs. 93.90 ng/g D.W.), respectively. Total gibberellin content was found to significantly increase in endophyte-inoculated plants (155.43–146.94?ng/g D.W.) as compared to that in controls (113.76 ng/g D.W.). In summary, bacterial endophytes might be used to enhance crop plant physiological characteristics isolated from arid land-inhabiting plants under normal conditions.  相似文献   
55.
Changes in the abundance and distribution of individual species have been widely documented in Britain and other countries in recent decades, but little has been done to determine changes in community composition over broad geographic areas. Here, we studied species turnover in 51 butterfly assemblages in Britain since 1976, examining extinction and colonisation events together with variation in the abundances of the species. We showed that the species turnover that occurred over 20 years in Britain was associated with colonisation and extinction events and also with variability in the abundance of the species. These changes in community composition differed according to the habitat requirements of the species and their previous distributions, being more evident for habitat specialists and for southerly distributed species. Colonising species often became abundant components of the communities they joined, although this was more evident for generalist than for specialist species. The abundance of species following their arrival, increased with time since colonisation. Species turnover associated with southerly species expanding northwards is consistent with being a response to climate change. The results suggest that climate- and habitat-driven changes in the identity and abundance of species within communities are widespread, and probably ubiquitous. Similar changes are likely to be occurring in other groups of organisms that are similarly undertaking major range shifts associated with climate change.  相似文献   
56.
Studies of sibling competition within brood hierarchies have rarely assessed simultaneously the effects of sex and rank in the brood hierarchy on traits other than offspring mortality and differential growth. We studied the expression of heat-shock proteins (Hsps) to assess the physiological stress response to different combinations of sex and position within competitive brood hierarchies in the black kite Milvus migrans (Bodd.), a sexually dimorphic raptor showing facultative siblicide. Senior males showed higher stress levels than did senior females and younger siblings of each sex as revealed by Hsp60 values. The analysis of Hsp70 levels indicated that nestlings from broods in which the senior chick was a male showed higher stress levels than did nestlings from broods in which the senior chick was a female. In addition, levels of Hsp60 were related negatively to nutritional condition expressed as levels of plasmatic albumin. This suggests that the sex of senior chicks may be key in determining their stress level and that of their siblings, which is probably associated with sibling competition by fighting within brood hierarchies. The comparatively higher stress levels of senior males (and their siblings) may be a consequence of their ability to exploit their potential advantage from being the head start while avoiding a possible competitive disadvantage from being the smaller sex, independent of environmental conditions determining the probability of brood reduction. Differential stress levels depending on sex and rank in the brood hierarchy may be a consequence of parental control of offspring behaviour through differential resource allocation (e.g. yolk androgens) or it may reflect adaptations of particular chicks (senior males) to enhance their competitive ability within brood hierarchies.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 383–390.  相似文献   
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The touchstone to evaluate accurately the aggressiveness and invasiveness of prostate cancer is something of a holy grail in the facet of urologic oncology. Gene expression and sequencing studies have improved our interpretations of the genetic determinants of the disease but are unsuccessful in the establishment of any unified classification to improve the molecular stratification. These questions addressing failure in rational drug design are difficult to answer in the multifaceted and heterogeneous pathogenesis of prostate cancer. In this review, we have developed a roadmap of the "recalcitrant prostate cancer proteome" to recognize the aspects of prostate cancer that may be helpful in effectively translating these findings to the clinic.  相似文献   
59.
High temperature strongly hampers the plant growth particularly at early growth stages. In this study, changes in some physiological and anatomical characteristics and possibility of mitigating the adversities of heat stress by soaking sugarcane nodal buds in 20 mM proline and glycinebetaine (GB) solutions have been explored. Heat stress reduced the rate of bud sprouting nonetheless soaking the setts in proline followed by GB was beneficial. In addition, heat stress reduced the bud fresh and dry weights, generated H2O2, reduced the tissue levels of K+ and Ca2+, while increased the osmolytes synthesis in a time course manner. Heat stress also delayed the emergence and expansion of new bud leaves, by restricting the number and area of mesophyll cells. It also caused poor and aberrant development and diffused appearance of mesophyll cells and vascular bundles in the bud leaves. However, soaking of buds in proline and GB solutions substantially reduced the H2O2 production, improved the accumulation of soluble sugars and protected the developing tissues from heat stress effects; although proline was more effective than GB. Correlations of various attributes indicated that soaking in GB and proline restricted the H2O2 generation, improved K+ and Ca2+ contents, and increased the concentrations of free proline, GB and soluble sugars eventually improving the heat tolerance of buds. Cost-benefit analysis showed that, considering increase in sprouting of buds, soaking in 20 mM solution of both osmoprotectants is economical.  相似文献   
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