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11.
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12.
Jeffrey M. Donlea Diogo Pimentel Clifford B. Talbot Anissa Kempf Jaison J. Omoto Volker Hartenstein Gero Miesenböck 《Neuron》2018,97(2):378-389.e4
13.
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
14.
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
15.
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
16.
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
17.
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
18.
Sana Ouali Manel Ben Halima Selim Boudiche Anissa Gharbi Khedher Nadim Kaouthar Hakim Fatma Ouarda Mohamed Sami Mourali 《Indian pacing and electrophysiology journal》2018,18(2):76-79
A 04-year-old boy was referred to our institution with severe, progressive heart failure of 4-months duration associated with a persistent wide QRS tachycardia with left bundle branch block and severe left ventricular dysfunction. Because of incessant wide QRS tachycardia refractory to antiarrhythmic drugs, he was referred for electrophysiological study. The ECG was suggestive of VT arising from the right ventricle near the His area. Electrophysiological study revealed that origin of tachycardia was septum of the right ventricle, near His bundle, however the procedure was not successful and an inadvertent complete atrioventricular conduction block occurred. The same ventricular tachycardia recurred. A second procedure was performed with a retrograd aortic approach to map the left side of the interventricular septum. The earliest endocardial site for ablation was localized in the anterobasal region of left ventricle near His bundle. In this location, one radiofrequency pulse interrupted VT and rendered it not inducible. The echocardiographic evaluation showed partial reversal of left ventricular function in the first 3 months. The diagnosis was idiopathic parahisian left ventricular tachycardia leading to a tachycardia mediated cardiomyopathy, an extremely rare clinical picture in children. 相似文献
19.
Anissa Lounès Ahmed Lebrihi Chouki Benslimane Gérard Lefebvre Pierre Germain 《Current microbiology》1995,31(5):304-311
Spiramycin production by Streptomyces ambofaciens in a chemically defined medium, with valine as nitrogen source, was controlled by the nature and the concentration of the carbon source. The production of this antibiotic was better in dextrins than in glycerol-containing medium. The negative effect of glycerol could be attributed in part to an excess of energy and a high specific growth rate. The intracellular ATP content, at the start of spiramycin production, was twofold higher in glycerol than in dextrin-containing medium. Increasing the initial concentrations of glycerol led to an increase in the specific growth rate and a drop in spiramycin production. Comparison between glycerol and a protein synthesis inhibitor effects and the use of resting cell systems (RCS) proved that glycerol exerted both inhibitory and repressive actions on spiramycin production independently from the growth. At the enzymatic level, glycerol interfered with valine catabolism by repressing partially valine dehydrogenase (VDH) and -ketoisoisovalerate dehydrogenase (KIVDH), generator of spiramycin aglycone precursors. 相似文献
20.