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81.
Succinate dehydrogenase inhibitor (SDHI) fungicides constitute a relatively recent fungicide class registered for the treatment of grey mould on grapevine in Italy. The sensitivity profile to a novel compound fluopyram was established for a set of 203 Botrytis cinerea isolates collected from Sicilian vineyards within 2009–2012 prior its introduction into market. In addition, its performances were compared in in vitro and in vivo assays with other registered SDHI fungicide boscalid, to evaluate their frequency distributions EC50 values and cross‐resistance patterns. Results of the article showed that EC50 values for fluopyram ranged from 0.05 to 1.98 µg mL?1. Although EC50 values of boscalid ranged from 0.01 to 89.52 µg mL?1, no cross‐resistance relationship was observed between the two fungicides (r = 0.003; P = 0.964) within our B. cinerea population. On further confirming these data, boscalid failed in controlling grey mould infections when boscalid‐resistant isolates were inoculated on grape berries whereas fluopyram exhibited a good efficacy against the same isolates. This study represents the first report on the baseline sensitivity to fluopyram within B. cinerea population from Sicilian table grape vineyards in Italy, and it clearly shows the lack of cross‐resistance in vitro and in vivo between fluopyram and boscalid for the field pathogen isolates. These results provided useful information for managing of fungicide resistance suggesting that fluopyram could be a valid alternative to boscalid for the control of grey mould of table grape.  相似文献   
82.
83.
Recent studies suggest that magnetic susceptibility (MS) measurements can play an important role in identifying zones where microbial-mediated iron mineral transformations are occurring. Here we investigated the microbial community variations within zones of elevated MS in a petroleum hydrocarbon-contaminated aquifer near Bemidji, Minnesota, USA. Our main objective was to 1) identify the key microbial populations that may play a role in hydrocarbon degradation, 2) analyze which microbial populations could be connected to the elevated MS and 3) explore the use of non-destructive geophysical techniques as a tool to guide microbial sampling. Clone libraries based on the 16S rRNA gene revealed the presence of iron-reducing β-Proteobacteria in the vadose zone, whereas the free petroleum phase on the water table was characterized by a methanogenic consortium, in which the syntrophic δ-proteobacterium Smithella and the hydrogenotrophic Methanoregula predominated. Nonmetric multidimensional scaling (NMDS) found a close relationship between elevated MS values and the methanogenic hydrocarbon-degrading consortium. Our results suggest that magnetic susceptibility measurements can guide microbiologists to zones of active microbial biodegradation in aged petroleum spills.  相似文献   
84.
Bacterial inoculation may influence Brassica juncea growth and heavy metal (Ni, Cr, and Cd) accumulation. Three metal tolerant bacterial isolates (BCr3, BCd33, and BNi11) recovered from mine tailings, identified as Pseudomonas aeruginosa KP717554, Alcaligenes feacalis KP717561, and Bacillus subtilis KP717559 were used. The isolates exhibited multiple plant growth beneficial characteristics including the production of indole-3-acetic acid, hydrogen cyanide, ammonia, insoluble phosphate solubilization together with the potential to protect plants against fungal pathogens. Bacterial inoculation improved seeds germination of B. juncea plant in the presence of 0.1 mM Cr, Cd, and Ni, as compared to the control treatment. Compared with control treatment, soil inoculation with bacterial isolates significantly increased the amount of soluble heavy metals in soil by 51% (Cr), 50% (Cd), and 44% (Ni) respectively. Pot experiment of B. juncea grown in soil spiked with 100 mg kg?1 of NiCl2, 100 mg kg?1 of CdCl2, and 150 mg kg?1 of K2Cr2O7, revealed that inoculation with metal tolerant bacteria not only protected plants against the toxic effects of heavy metals, but also increased growth and metal accumulation of plants significantly. These findings suggest that such metal tolerant, plant growth promoting bacteria are valuable tools which could be used to develop bio-inoculants for enhancing the efficiency of phytoextraction.  相似文献   
85.
Manganese mining activities in the Drama district, northern Greece, have resulted in a legacy of abandoned mine wastes at the “25 km Mn-mine” site. Current research was focused on the western Drama plain (WDP), constituting the recipient of the effluents from Xiropotamos stream, which passes through the “25 km Mn-mine” place. A total of 148 top soil samples were collected and their heavy metals (HMs) concentrations (Mn, Pb, Zn, Cu, Cd, and As) were determined using inductively coupled plasma mass spectrometry. Enrichment factor (EF), geoaccumulation index (Igeo), and pollution load index (PLI) were calculated as an effort to assess metal accumulation, distribution, and pollution status of the soils due to the former mining activity. The overall potential ecological risk of HMs to the environment was also evaluated using the potential toxicity response index (RI). Results showed that peak values of the elements (13 wt% for Mn, 0.2 wt% for Pb, 0.2 wt% for Zn, 0.1 wt% for As, 153 mg/kg for Cu, and 27.5 mg/kg for Cd) were found in soils from sites close to and along both sides of the Xiropotamos stream. In this sector of WDP, values of EF, Igeo, and PLI classify the soils as moderately to highly polluted with Mn, Pb, Zn, Cd, and As. Based on RI values, soils in this part of WDP display considerable to very great potential ecological risk and, therefore, a remediation has to be applied. The main cause of soil contamination is considered the Xiropotamos downstream transfer and dispersion of Mn mine wastes via flooding episodes.  相似文献   
86.
目的:分析生物合成胰岛素注射液启封后有效期内细菌污染情况,并总结其合理的使用方法及时间。方法:收集我院各个科室使用的胰岛素注射液96瓶,启封后分别在不同使用时间和保存温度下采集样本进行细菌学检测。结果:本实验中96瓶启封后有效期内的生物胰岛素注射液中,共有10瓶细菌培养呈阳性,阳性率为10.41%。其中7d之内启封的胰岛素注射液细菌培养全部呈阴性,其余各组的胰岛素注射液细菌培养均呈阳性及存在菌落,随着启封时间的延长,细菌培养阳性率及菌落数上升,且各组之间的差异均具有统计学意义(P0.05)。研究中保存温度2~4℃的细菌培养全部呈阴性,其余各组的胰岛素注射液细菌培养均呈阳性及存在菌落,随着保存温度的升高,细菌培养阳性率及菌落数上升,且各组之间的差异均具有统计学意义(P0.05)。结论:胰岛素注射液启封后有效期内随着时间的延长以及保存温度的升高,细菌培养的阳性率及菌落数量上升,临床使用时要应尽量在7d内使用完,并且尽量保存在低于25℃环境中。  相似文献   
87.
Tuberculosis (TB) and human immunodeficiency virus type 1 (HIV‐1) infection are closely intertwined, with one‐quarter of TB/HIV coinfected deaths among people died of TB. Effector CD8+ T cells play a crucial role in the control of Mycobacterium tuberculosis (MTB) and HIV‐1 infection in coinfected patients. Adoptive transfer of a multitude of effector CD8+ T cells is an appealing strategy to impose improved anti‐MTB/HIV‐1 activity onto coinfected individuals. Due to extensive existence of heterologous immunity, that is, T cells cross‐reactive with peptides encoded by related or even very dissimilar pathogens, it is reasonable to find a single T cell receptor (TCR) recognizing both MTB and HIV‐1 antigenic peptides. In this study, a single TCR specific for both MTB Ag85B199‐207 peptide and HIV‐1 Env120‐128 peptide was screened out from peripheral blood mononuclear cells of a HLA‐A*0201+ healthy individual using complementarity determining region 3 spectratype analysis and transferred to primary CD8+ T cells using a recombinant retroviral vector. The bispecificity of the TCR gene‐modified CD8+ T cells was demonstrated by elevated secretion of interferon‐γ, tumour necrosis factor‐α, granzyme B and specific cytolytic activity after antigen presentation of either Ag85B199‐207 or Env120‐128 by autologous dendritic cells. To the best of our knowledge, this study is the first report proposing to produce responses against two dissimilar antigenic peptides of MTB and HIV‐1 simultaneously by transfecting CD8+ T cells with a single TCR. Taken together, T cells transduced with the additional bispecific TCR might be a useful strategy in immunotherapy for MTB/HIV‐1 coinfected individuals.  相似文献   
88.
Hypoxanthine‐guanine‐xanthine phosphoribosyltransference (HGXPRT), a key enzyme in the purine salvage pathway of the malarial parasite, Plasmodium falciparum (Pf), catalyses the conversion of hypoxanthine, guanine, and xanthine to their corresponding mononucleotides; IMP, GMP, and XMP, respectively. Out of the five active site loops (I, II, III, III', and IV) in PfHGXPRT, loop III' facilitates the closure of the hood over the core domain which is the penultimate step during enzymatic catalysis. PfHGXPRT mutants were constructed wherein Trp 181 in loop III' was substituted with Ser, Thr, Tyr, and Phe. The mutants (W181S, W181Y and W181F), when examined for xanthine phosphoribosylation activity, showed an increase in Km for PRPP by 2.1‐3.4 fold under unactivated condition and a decrease in catalytic efficiency by more than 5‐fold under activated condition as compared to that of the wild‐type enzyme. The W181T mutant showed 10‐fold reduced xanthine phosphoribosylation activity. Furthermore, molecular dynamics simulations of WT and in silico W181S/Y/F/T PfHGXPRT mutants bound to IMP.PPi.Mg2+ have been carried out to address the effect of the mutation of W181 on the overall dynamics of the systems and identify local changes in loop III'. Dynamic cross‐correlation analyses show a communication between loop III' and the substrate binding site. Differential cross‐correlation maps indicate altered communication among different regions in the mutants. Changes in the local contacts and hydrogen bonding between residue 181 with the nearby residues cause altered substrate affinity and catalytic efficiency of the mutant enzymes. Proteins 2016; 84:1658–1669. © 2016 Wiley Periodicals, Inc.  相似文献   
89.
A wide variety of fungi and bacteria are known to contaminate fuels and fuel systems. These microbial contaminants have been linked to fuel system fouling and corrosion. The fungus Hormoconis resinae, a common jet fuel contaminant, is used in this study as a model for developing innovative risk assessment methods. A novel qPCR protocol to detect and quantify H. resinae in, and together with, total fungal contamination of fuel systems is reported. Two primer sets, targeting the markers RPB2 and ITS, were selected for their remarkable specificity and sensitivity. These primers were successfully applied on fungal cultures and diesel samples demonstrating the validity and reliability of the established qPCR protocol. This novel tool allows clarification of the current role of H. resinae in fuel contamination cases, as well as providing a technique to detect fungal outbreaks in fuel systems. This tool can be expanded to other well-known fuel-deteriorating microorganisms.  相似文献   
90.
Serum is an important component of cell culture media. The present study demonstrates contamination of intracellular protein extract by bovine serum albumin from the culture media and illustrates how this contamination can cause the misinterpretation of western blot results. Preliminary experiments can prevent the misinterpretation of some experimental results, and optimization of the washing process may enable specific protein detection.  相似文献   
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