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Anissa Belkaid Jean-Christophe Currie Julie Desgagnés Borhane Annabi 《Cancer cell international》2006,6(1):7-12
Background
Chlorogenic acid (CHL), the most potent functional inhibitor of the microsomal glucose-6-phosphate translocase (G6PT), is thought to possess cancer chemopreventive properties. It is not known, however, whether any G6PT functions are involved in tumorigenesis. We investigated the effects of CHL and the potential role of G6PT in regulating the invasive phenotype of brain tumor-derived glioma cells. 相似文献13.
R. Khan N. Alkharouf H. Beard M. MacDonald I. Chouikha S. Meyer J. Grefenstette H. Knap B. Matthews 《Journal of nematology》2004,36(3):241-248
Soybean root cells undergo dramatic morphological and biochemical changes during the establishment of a feeding site in a compatible interaction with the soybean cyst nematode (SCN). We constructed a cDNA microarray with approximately 1,300 cDNA inserts targeted to identify differentially expressed genes during the compatible interaction of SCN with soybean roots 2 days after infection. Three independent biological replicates were grown and inoculated with SCN, and 2 days later RNA was extracted for hybridization to microarrays and compared to noninoculated controls. Statistical analysis indicated that approximately 8% of the genes monitored were induced and more than 50% of these were genes of unknown function. Notable genes that were more highly expressed 2 days after inoculation with SCN as compared to noninoculated roots included the repetitive proline-rich glycoprotein, the stress-induced gene SAM22, ß-1,3-endoglucanase, peroxidase, and those involved in carbohydrate metabolism, plant defense, and signaling. 相似文献
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Jeffrey M. Donlea Diogo Pimentel Clifford B. Talbot Anissa Kempf Jaison J. Omoto Volker Hartenstein Gero Miesenböck 《Neuron》2018,97(2):378-389.e4
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Yamouna Makhlouf Ahmed Nedjari Anissa Dahoumane Elise Nardin Martina Nohejlová Bertrand Lefebvre 《Annales de Paléontologie》2018,104(4):301-307
Several specimens of the genus Ascocystites (Blastozoa, Eocrinoidea) are described for the first time in Late Ordovician deposits (Bou M’Haoud Formation) from the Ougarta Range, Algeria. This genus was previously known in Darriwilian–Sandbian deposits of four other areas of the Mediterranean Province (Czech Republic, France, Morocco and Portugal). The Algerian material completes its palaeobiogeographic distribution in the peri-Gondwanan area, restricted in shallow water settings. 相似文献
16.
Ral Gagnon Maurice Levasseur Andrea M. Weise Juliette Fauchot Peter G. C. Campbell Bryan J. Weissenboeck Anissa Merzouk Michel Gosselin Bernard Vigneault 《Journal of phycology》2005,41(3):489-497
In the St. Lawrence Estuary, annual recurrent blooms of the toxic dinoflagellate Alexandrium tamarense L. Balech are associated with brackish waters. Riverine inputs are suspected to favor bloom development by increasing water column stability and/or by providing growth stimulants such as humic substances (HS). A 17‐day culture experiment was conducted to evaluate the importance of HS as growth factors for A. tamarense. Nonaxenic cultures were exposed to four HS extracts from three different sources: humic and fulvic acids isolated from the Manicouagan River, Quebec, Canada; humic acids from the Suwannee River, Georgia, United States; and a desalted alkaline soil extract. For each extract, four concentrations were tested as supplements to the artificial Keller medium, a nitrate‐rich algal culture medium. Additions of HS from all sources significantly enhanced the overall growth rates relative to the controls. Concentrations of HS, estimated by UV spectrophotometry, remained constant throughout the exponential growth phase, suggesting that the HS were acting mainly as growth promoters during our experiment. Dose–response curves indicated that HS could increase the growth rate of A. tamarense even at low concentrations, such as those encountered in the St. Lawrence Estuary. Our results support the hypothesis that HS from the Manicouagan River plume can stimulate the development of toxic dinoflagellate blooms. 相似文献
17.
Gui-Peng Yang Maurice Levasseur Sonia Michaud Anissa Merzouk Martine Lizotte Michael Scarratt 《Biogeochemistry》2009,94(3):243-254
One of the key steps towards predicting dimethylsulfide (DMS) emission to the atmosphere is to understand the distribution
and cycling of biogenic sulfur in the microlayer. In this study, we examined the distribution of DMS and dissolved and particulate
fractions of dimethylsulfoniopropionate (DMSPd and DMSPp) in the surface microlayer and bulk water of the western North Atlantic
during July 2003. DMS concentrations in the bulk water varied from 0.71 to 7.65 nM. In contrast, DMS concentrations in the
surface microlayer were fairly low (0.17–1.33 nM). Average concentrations of DMSPd and DMSPp in the bulk water were 2.09 (1.87–6.25)
and 44.1 (8.06–119.8) nM, respectively, and those in the surface microlayer were 15.4 (4.06–54.3) and 29.9 (7.32–97.0) nM.
In general, DMS was depleted in the microlayer (mean concentration: 0.60 nM) relative to the bulk water (mean concentration:
2.38 nM) with enrichment factors (the ratio of the microlayer concentration to bulk water concentration) ranging from 0.13
to 0.54. There was no consistent enrichment of DMSPp and chlorophyll a in the microlayer. On the contrary, DMSPd appeared to be highly enriched in the microlayer with an average EF of 4.89. The
concentration of phaeopigments was also generally greater in the microlayer than in the bulk water, presumably due to enhanced
photo-oxidation of chlorophyll a under high surface light intensities in the microlayer. In the study area, the concentration of DMSPp was significantly correlated
with the abundance of dinoflagellates in the microlayer. Moreover, a significant correlation between the distributions of
DMS, DMSPp, chlorophyll a and phaeopigment concentrations in the microlayer and the bulk water demonstrated that the biogenic materials in the microlayer
come primarily from the bulk water below. 相似文献
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Schouler C Taki A Chouikha I Moulin-Schouleur M Gilot P 《Journal of bacteriology》2009,191(1):388-393
Prebiotics such as fructooligosaccharides (FOS) are increasingly being used in some countries for improving human and animal health and as an alternative to antibiotic growth promoters in animals, with various degrees of success. It has been observed that FOS stimulate the proliferation of probiotic bacteria and, at the same time, decrease the population of bacteria associated with disease. This observation assumes that pathogenic bacteria do not metabolize FOS and, therefore, lose their competitive advantage over beneficial bacteria. Here we present evidence that some pathogenic Escherichia coli strains can metabolize FOS and show that this property helps the bacterium colonize the intestine. These findings highlight the potential risk that a high level of prebiotic usage could lead to the emergence of well-adapted pathogenic strains that metabolize prebiotic substances. 相似文献
19.
Noomen Hmidet Nedra El Hadj Ali Nahed Zouari-Fakhfakh Anissa Haddar Moncef Nasri Alya Sellemi-Kamoun 《Journal of industrial microbiology & biotechnology》2010,37(9):983-990
This study is concerned with the co-production of alkaline proteases and thermostable α-amylase by some feather-degrading
Bacillus strains: B. mojavensis A21, B. licheniformis NH1, B. subtilis A26, B. amyloliquefaciens An6 and B. pumilus A1. All strains produced both enzymes, except B. pumilus A1, which did not exhibit amylolytic activity. The best enzyme co-production was obtained by the NH1 strain when chicken
feathers were used as nitrogen and carbon sources in the fermentation medium. The higher co-production of both enzymes by
B. licheniformis NH1 strain was achieved in the presence of 7.5 g/l chicken feathers and 1 g/l yeast extract. Strong catabolic repression
on protease and α-amylase production was observed with glucose. Addition of 0.5% glucose to the feather medium suppressed
enzyme production by B. licheniformis NH1. The growth of B. licheniformis NH1 using chicken feathers as nitrogen and carbon sources resulted in its complete degradation after 24 h of incubation at
37°C. However, maximum protease and amylase activities were attained after 30 h and 48 h, respectively. Proteolytic activity
profiles of NH1 enzymatic preparation grown on chicken feather or casein-based medium are different. As far as we know, this
is the first contribution towards the co-production of α-amylase and proteases using keratinous waste. Strain NH1 shows potential
use for biotechnological processes involving keratin hydrolysis and industrial α-amylase and proteases co-production. Thus,
the utilization of chicken feathers may result in a cost-effective process suitable for large-scale production. 相似文献
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Anthony Verdin Anissa Louns-Hadj Sahraoui Frdric Laruelle Anne Grandmougin-Ferjani Roger Durand 《Mycological Research》2006,110(4):479-484
The purpose of the present paper was to study the effect of the high polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene, on the lipid [fatty acid (FA) and sterol] composition and content of the fungi Fusarium solani and F. oxysporum, respectively recognized as good and poor PAH degraders. The major FAs and the major sterol that characterized the tested Fusarium strains were C16:0, C18:1, C18:2, and ergosterol. Lipid profiles of F. solani remained unchanged with the addition of benzo[a]pyrene in the culture media at all concentrations and duration of treatment. However, in the presence of benzo[a]pyrene, significant decreases in FA content, which reached 18 % in young cultures and 28 % in mature colonies, were registered. Similarly, the sterol content of F. solani was reduced by 27 % in the presence of benzo[a]pyrene. In contrast, no modification in lipid profile and lipid content were observed with F. oxysporum, a strain recognized as a low benzo[a]pyrene degrader. 相似文献