排序方式: 共有124条查询结果,搜索用时 31 毫秒
61.
Hamdi F Fargues J Ridray G Jeannequin B Bonato O 《Journal of invertebrate pathology》2011,108(1):22-29
The effect of the combined use of Encarsia formosa or Macrolophus caliginosus and one of three marketed mycoinsecticides, Mycotal® (Leucanicillium muscarium-based), Naturalis-L™ (Beauveria bassiana-based) and PreFeRal® (Isaria fumosorosea-based), on the control of the whitefly, Trialeurodes vaporariorum, was studied under laboratory and greenhouse conditions. The results of both types of tests, the bioassays and the greenhouse trials, for all combinations of E. Formosa with each of the three mycoinsecticides showed that the total mortality of larval populations of T. vaporariorum was not affected. The mortality of T. vaporariorum larvae treated in the second instar revealed the capacity for both B. bassiana- and L. muscarium-based formulations and E. formosa to kill the host either separately or in association. Because of its higher pathogenic activity (under our test conditions), L. muscarium provoked a large proportion of mycoses in larvae exposed to parasitization. In contrast, the efficacy of parasitization was higher in larvae treated with B. bassiana and exposed to E. formosa because of a lower pathogenic activity of the fungus. Bioassays carried out with third-instar larvae of T. vaporariorum showed a low susceptibility to both tested fungi. Consequently, mortalities recorded in larvae subjected to the combined treatments by consecutive exposures or at 2-4 days post-parasitization were mainly caused by the development of the parasitoid. Greenhouse trials showed that fungus-induced mortality of T. vaporariorum in plants treated with L. muscarium, I. fumosorosea, and B. Bassiana was significant compare to control. L. muscarium, B. bassiana and I. fumosorosea killed young whitefly larvae and limited parasitization to 10% or less. Second-instar larvae of M. caliginosus were not susceptible to L. muscarium and B. bassiana formulations with any mode of contamination: direct spraying of larvae, spraying on the foliar substrate or by contaminated T. vaporariorum prey. In greenhouse trials, M. caliginosus populations treated with fungi were not significantly affected compared to controls. 相似文献
62.
In the present study, the abattoir digestate was used as a culture medium for Spongiochloris sp. growth with added mineral components under optimized conditions in batch culture. Firstly, an Hadamard matrix was used to investigate the impact of certain influencing factors on the Spongiochloris sp. growth. Then, a fractional factorial design 27-4 was successfully employed to optimize the concentration of different added components to abattoir digestate for increased Spongiochloris sp. biomass production. The major influencing factors were NaHCO3 and FeSO4 at a level of 2000 mg/L and 5 mg/L, respectively. A high biomass production of 5.29 × 106 cell/mL and an important content of chlorophyll a of 65.32 mg/L were obtained after 42 days of culture of Spongiochloris sp. on the defined abattoir medium at static conditions. 相似文献
63.
Moussa Louati Nathaniel J. Ennis Faten Ghodhbane-Gtari Karima Hezbri Joseph L. Sevigny Maria F. Fahnestock Hafsa Cherif-Silini Julia G. Bryce Louis S. Tisa Maher Gtari 《Environmental microbiology》2020,22(4):1467-1480
Stone surfaces are extreme environments that support microbial life. This microbial growth occurs despite unfavourable conditions associated with stone including limited sources of nutrients and water, high pH and exposure to extreme variations in temperature, humidity and irradiation. These stone-dwelling microbes are often resistant to extreme environments including exposure to desiccation, heavy metals, UV and Gamma irradiation. Here, we report on the effects of climate and stone geochemistry on microbiomes of Roman stone ruins in North Africa. Stone microbiomes were dominated by Actinobacteria, Cyanobacteria and Proteobacteria but were heavily impacted by climate variables that influenced water availability. Stone geochemistry also influenced community diversity, particularly through biologically available P, Mn and Zn. Functions associated with photosynthesis and UV protection were enriched in the metagenomes, indicating the significance of these functions for community survival on stones. Core members of the stone microbial communities were also identified and included Geodermatophilaceae, Rubrobacter, Sphingomonas and others. Our research has helped to expand the understanding of stone microbial community structure and functional capacity within the context of varying climates, geochemical properties and stone conditions. 相似文献
64.
65.
Essential Oil Variability in Natural Populations of Artemisia campestris (L.) and Artemisia herba‐alba (Asso) and Incidence on Antiacetylcholinesterase and Antioxidant Activities 下载免费PDF全文
Faten Younsi Sameh Mehdi Oumayma Aissi Najoua Rahali Rym Jaouadi Mohamed Boussaid Chokri Messaoud 《化学与生物多样性》2017,14(7)
The intraspecific variability of Artemisia herba‐alba and A. campestris essential oils and the evaluation of their antioxidant and antiacetylcholinesterase activities were determined. Artemisia herba‐alba essential oil was found rich in camphor (19.61%), α‐thujone (19.40%), β‐thujone (9.44%), chrysanthenone (9.26%), and trans‐sabinyl acetate (8.43%). The major compounds of A. campestris essential oil were germacrene D (16.38%), β‐pinene (16.33%), and limonene (9.17%). Significant variation in the essential oil composition was observed among populations of each species. The divergence between populations was attributed to the variation of some climatic factors such as altitude, annual rainfall, winter cold stress, summer precipitation, summer drought stress, evapotranspiration, and humidity. Artemisia herba‐alba and A. campestris essential oils exhibited promising antioxidant and antiacetylcholinesterase activities. The level of activity varied significantly according to the species and the essential oil. The highest scavenging activity (IC50 = 0.14 mg/ml) and the uppermost capacity to prevent β‐carotene bleaching (IC50 = 0.10 mg/ml) characterized A. campestris from population 6. A. campestris population 3 possessed the uppermost ability to reduce ferric ions (450.7 μmol Fe2+/g EO). The population 2 of A. campestris showed the strongest antiacetylcholinesterase activity (IC50 = 0.02 mg/ml). The variation of these activities between the essential oils was explained by their composition differences. 相似文献
66.
Bekesho Geleta Faten S. Tout Syer Choon Lim Sumit Sahni Patric J. Jansson Minoti V. Apte Des R. Richardson
aklina Kova
evi 《The Journal of biological chemistry》2022,298(3)
A major barrier to successful pancreatic cancer (PC) treatment is the surrounding stroma, which secretes growth factors/cytokines that promote PC progression. Wnt and tenascin C (TnC) are key ligands secreted by stromal pancreatic stellate cells (PSCs) that then act on PC cells in a paracrine manner to activate the oncogenic β-catenin and YAP/TAZ signaling pathways. Therefore, therapies targeting oncogenic Wnt/TnC cross talk between PC cells and PSCs constitute a promising new therapeutic approach for PC treatment. The metastasis suppressor N-myc downstream-regulated gene-1 (NDRG1) inhibits tumor progression and metastasis in numerous cancers, including PC. We demonstrate herein that targeting NDRG1 using the clinically trialed anticancer agent di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC) inhibited Wnt/TnC-mediated interactions between PC cells and the surrounding PSCs. Mechanistically, NDRG1 and DpC markedly inhibit secretion of Wnt3a and TnC by PSCs, while also attenuating Wnt/β-catenin and YAP/TAZ activation and downstream signaling in PC cells. This antioncogenic activity was mediated by direct inhibition of β-catenin and YAP/TAZ nuclear localization and by increasing the Wnt inhibitor, DKK1. Expression of NDRG1 also inhibited transforming growth factor (TGF)-β secretion by PC cells, a key mechanism by which PC cells activate PSCs. Using an in vivo orthotopic PC mouse model, we show DpC downregulated β-catenin, TnC, and YAP/TAZ, while potently increasing NDRG1 expression in PC tumors. We conclude that NDRG1 and DpC inhibit Wnt/TnC-mediated interactions between PC cells and PSCs. These results further illuminate the antioncogenic mechanism of NDRG1 and the potential of targeting this metastasis suppressor to overcome the oncogenic effects of the PC-PSC interaction. 相似文献
67.
Nina Desai Faten AbdelHafez Edmund Sabanegh James Goldfarb 《Reproductive biology and endocrinology : RB&E》2009,7(1):142-7
Background
This study takes an in depth look at embryonic development, implantation, pregnancy and live birth rates with frozen epididymal and testicular sperm from obstructed (OA) and non-obstructed (NOA) patients. 相似文献68.
Nicole Zarrett Michelle Abraczinskas Brittany Skiles Cook Dawn K. Wilson Faten Ragaban 《应用发育科学》2018,22(1):58-73
Afterschool programs (ASPs) have become increasingly recognized as a key context to support youth daily physical activity (PA) accrual. Using Self-Determination Theory (SDT) as a framework, this study examined staff perspectives on the strengths and barriers within under-resourced ASPs for establishing a social-motivational climate for encouraging and supporting youth PA. Analysis of semi-structured staff interviews (28 staff; 7 ASPs) indicated that staff had knowledge and value for establishing a PA-supportive motivational climate. However, the feasibility of implementing PA curricula was identified as challenging across programs. Findings suggest increased need for staff training and supports to provide a PA climate that meets the developmental needs/interests of all youth, with particular attention toward increasing the PA of girls and older program youth. Furthermore, striking an appropriate balance between PA and other competing program demands (e.g., academics) will be required to optimize on the effectiveness of PA program components. 相似文献
69.
Faten Ghodhbane-Gtari Imene Essoussi Mayssa Chattaoui Bessem Chouaia Atef Jaouani Daniele Daffonchio Abdellatif Boudabous Maher Gtari 《Symbiosis (Philadelphia, Pa.)》2010,50(1-2):51-57
Actinobacterial isolates randomly obtained on nitrogen-free BAP medium from surface sterilized root nodules of Alnus glutinosa, Casuarina glauca and Elaeagnus angustifolia sampled from fields were reported. They were assigned on the basis of partial 16S rRNA sequences to Micromonospora, Nocardia and Streptomyces genera. The isolates have been screened for hydrolytic activities, indole acetic acid (IAA) and siderophores production, phosphate solubilization and antagonistic activities. Results suggest putative traits as plant growth promoting bacteria proprieties of the isolates that occur in unique association in root nodules of the three analysed actinorhizal host species. 相似文献
70.
Riadh Marrouchi Faten Dziri Nawel Belayouni Asma Hamza Evelyne Benoit Jordi Molgó Riadh Kharrat 《Marine biotechnology (New York, N.Y.)》2010,12(5):579-585
Quantitative determination by high performance liquid chromatography (HPLC) was performed for gymnodimine-A (GYM-A), a phycotoxin
responsible for the contamination of Tunisian clams. This study demonstrates a rapid and reproducible HPLC-ultraviolet (UV)
method for extraction, detection and quantification of GYM-A in toxic clams. The extraction of GYM-A from the digestive gland
of clams in acetone, subsequent clean-up with diethyl ether and extraction with dichloromethane is the more valid protocol.
Chromatography analyses were performed using a gradient of acetonitrile–water (10:90 to 90:10), containing trifluoroacetic
acid (0.1%) for 20 min at 1 mL/min rate with a C18 column. Recovery rates exceeded 96%, and limits of detection and quantification
were 5 ng/mL and 8 ng/g digestive gland, respectively. Repeatability and reproducibility were tested for various samples containing
different levels of GYM-A. A significant correlation was observed between toxicity level of samples and the determined amount
of GYM-A. Also, the persistence of GYM-A in contaminated clams from Boughrara lagoon was demonstrated. The kinetics discharge
study of GYM-A in controlled medium, during 1 month, showed that the process of depuration was biphasic with an exponential
discharge of 75% of the total amount of sequestered GYM-A during the first 12 days followed by a slow discharge (>10%) for
the subsequent days up to the seventeenth day. This is the first time that a quantitative study of GYM-A in clams from Tunisian
coasts is performed through the development of a new method for detection and quantify of this phycotoxin. We found HPLC-UV
a reliable and suitable alternative to the mouse bioassay. 相似文献