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51.
Nadia Jrad-Battikh Amira Souii Rym Hadhri Mahjoub Aouni Jawhar Gharbi Manel Ben M’hadheb-Gharbi 《Biologia》2014,69(1):113-121
We have previously addressed the question of whether the attenuating mutations of domain V of the Poliovirus IRES were specific for a given genomic context or whether they could be extrapolated to a genomic related virus, the Coxsackievirus B3 (CVB3). Accordingly, we have described that Sabin3-like mutation (U473→C) introduced in the CVB3 genome led to a defective mutant with a serious reduction in translation efficiency. In this study, we assessed the protection provided by the Sabin3-like mutant against CVB3 infection. For this purpose, we analyzed, in vivo, the Sabin3-like phenotype in Swiss mice inoculated with CVB3 and CVB4 E2 prototype strains either by oral or intraperitoneal (i.p) routes and explored the capacity of this mutant to act as a vaccine vector after the challenge. The Sabin3-like RNA was detected by semi-nested PCR in different organs: heart, pancreas and intestine at 10 days post-inoculation with both oral and i.p routes. Additionally, we did not observe any histological alterations in heart and intestine tissues. RNA was detected in the different organs of all mice immunized with the Sabin3-like strain and challenged with either CVB3 or CVB4 E2 by oral route at 7 days post-challenge. In contrast, no histological alteration of heart or pancreas tissues was observed after challenge with both wild-strains. Interestingly, the detection of viral RNA in heart, pancreas and intestine of mice immunized by i.p route was negative at 7 days post-challenge with CVB3 and CVB4 E2, and mice were protected from myocarditis and pancreatitis. 相似文献
52.
Marck C Kachouri-Lafond R Lafontaine I Westhof E Dujon B Grosjean H 《Nucleic acids research》2006,34(6):1816-1835
We present the first comprehensive analysis of RNA polymerase III (Pol III) transcribed genes in ten yeast genomes. This set includes all tRNA genes (tDNA) and genes coding for SNR6 (U6), SNR52, SCR1 and RPR1 RNA in the nine hemiascomycetes Saccharomyces cerevisiae, Saccharomyces castellii, Candida glabrata, Kluyveromyces waltii, Kluyveromyces lactis, Eremothecium gossypii, Debaryomyces hansenii, Candida albicans, Yarrowia lipolytica and the archiascomycete Schizosaccharomyces pombe. We systematically analysed sequence specificities of tRNA genes, polymorphism, variability of introns, gene redundancy and gene clustering. Analysis of decoding strategies showed that yeasts close to S.cerevisiae use bacterial decoding rules to read the Leu CUN and Arg CGN codons, in contrast to all other known Eukaryotes. In D.hansenii and C.albicans, we identified a novel tDNA-Leu (AAG), reading the Leu CUU/CUC/CUA codons with an unusual G at position 32. A systematic 'p-distance tree' using the 60 variable positions of the tRNA molecule revealed that most tDNAs cluster into amino acid-specific sub-trees, suggesting that, within hemiascomycetes, orthologous tDNAs are more closely related than paralogs. We finally determined the bipartite A- and B-box sequences recognized by TFIIIC. These minimal sequences are nearly conserved throughout hemiascomycetes and were satisfactorily retrieved at appropriate locations in other Pol III genes. 相似文献
53.
Rym Kaddour Emna Draoui Olfa Baâtour Hela Mahmoudi Imen Tarchoun Nawel Nasri Margaret Gruber Mokhtar Lachaâl 《Acta Physiologiae Plantarum》2013,35(12):3427-3436
Nasturtium officinale R. Br. seedlings were treated with a range of NaCl concentrations (0, 50, 100 and 150 mM) for 21 days after seedling emergence. Physiological analysis based on growth and mineral nutrition, showed a substantial decrease in leaf dry matter with 150 mM NaCl treatment. The growth decrease was correlated with nutritional imbalance and a reduction in potassium accumulation and transport to the leaves. At the same time, we noted an increase in leaf sodium and chloride accumulation and transport. Salt tolerance of N. officinale under 100 mM NaCl was associated with osmotic adjustment via Na+ and Cl? and the maintenance of high K+/Na+ selectivity. Salt decreased carotenoid content more than chlorophylls and also disturbed membrane integrity by increasing malondialdehyde content and electrolyte leakage. At 150 mM NaCl, an increase in antioxidant enzyme-specific activities for superoxide dismutase, catalase and guaiacol peroxidase occurred in concert with a decrease in ascorbic acid, polyphenol, tannin and flavonoid content. These results indicate that N. officinale can maintain growth and natural antioxidant defense compounds such as, vitamin C, carotenoids, and polyphenols, when cultivated in 100 mM NaCl, but not at higher salt levels. 相似文献
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Abderrahmani R François A Buard V Tarlet G Blirando K Hneino M Vaurijoux A Benderitter M Sabourin JC Milliat F 《PloS one》2012,7(4):e35740
Normal tissue toxicity still remains a dose-limiting factor in clinical radiation therapy. Recently, plasminogen activator inhibitor type 1 (SERPINE1/PAI-1) was reported as an essential mediator of late radiation-induced intestinal injury. However, it is not clear whether PAI-1 plays a role in acute radiation-induced intestinal damage and we hypothesized that PAI-1 may play a role in the endothelium radiosensitivity. In vivo, in a model of radiation enteropathy in PAI-1 -/- mice, apoptosis of radiosensitive compartments, epithelial and microvascular endothelium was quantified. In vitro, the role of PAI-1 in the radiation-induced endothelial cells (ECs) death was investigated. The level of apoptotic ECs is lower in PAI-1 -/- compared with Wt mice after irradiation. This is associated with a conserved microvascular density and consequently with a better mucosal integrity in PAI-1 -/- mice. In vitro, irradiation rapidly stimulates PAI-1 expression in ECs and radiation sensitivity is increased in ECs that stably overexpress PAI-1, whereas PAI-1 knockdown increases EC survival after irradiation. Moreover, ECs prepared from PAI-1 -/- mice are more resistant to radiation-induced cell death than Wt ECs and this is associated with activation of the Akt pathway. This study demonstrates that PAI-1 plays a key role in radiation-induced EC death in the intestine and suggests that this contributes strongly to the progression of radiation-induced intestinal injury. 相似文献
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Rym Kaddour Olfa Baatour Hela Mahmoudi Nawel Nasri Maha Zaghdoudi Mokhtar Lachaâl 《Acta Physiologiae Plantarum》2011,33(6):2083-2090
The response to salt treatment and K+ provision of two Arabidopsis thaliana accessions grown for 17 days in the presence of 50 mM NaCl was investigated. Leaf and root dry weight deposition was restricted
by salt, more in Col accession than in NOK2 accession. In both accessions, the growth inhibition induced by salinity was associated
with a decrease in total leaf surface area, which resulted from diminished leaf number, but not from restriction of individual
leaf surface area. Comparing the effects of salt on dry matter production and total leaf surface area revealed large difference
between Col and NOK2 for net assimilation rate (the amount of whole plant biomass produced per unit leaf surface area), which
was augmented by salt and K+ in NOK2 but not in Col. This result, which suggested a better capacity of NOK2 to preserve its photosynthetic machinery against
salt stress, was in agreement with the effect of NaCl on photosynthetic pigments. Indeed, salt significantly reduced chlorophyll
and carotenoid content in Col leaves but had no impact on NOK2 leaf pigment content. Since K+ provision had only marginal effects on these responses to salt stress, leaf mineral unbalance was unlikely. Guaiacol peroxidase
activity was augmented by salt treatment in leaves and roots of both accessions. Salinity decreased the catalase activity
in Col leaves and in roots, and increased this activity in NOK2 organs. In conclusion, when aggressed by salt, NOK2 was able
(1) to produce more leaves than Col, and (2) to efficiently protect its photosynthetic apparatus, perhaps by developing more
efficient antioxidative defense through increased catalase and peroxidase activities. Consequently, the overall photosynthetic
activity was higher and more robust to salt aggression in NOK2 than in Col. 相似文献
58.
Ben Slama K Ben Sallem R Jouini A Rachid S Moussa L Sáenz Y Estepa V Somalo S Boudabous A Torres C 《Current microbiology》2011,62(6):1794-1801
Fourteen broad-spectrum-cephalosporin-resistant Escherichia
coli isolates were recovered between June and December 2007 in a Tunisian hospital. Genes encoding extended-spectrum-beta-lactamases
(ESBL) and other resistance genes were characterized by PCR and sequencing. The following ESBL genes were identified: bla
CTX-M-15 (12 isolates), bla
CTX-M-14a (one isolate), and bla
CTX-M-14b (one isolate). The bla
OXA-1 gene was detected in 13 bla
CTX-M-producing strains and a bla
TEM-1 gene in 6 of them. The ISEcp1 sequence was found upstream of bla
CTX-M genes in 8 of 14 strains, and orf477 or IS903 downstream of this gene in 13 strains. Nine of the strains carried class 1 integrons and five different gene cassette arrangements
were detected, dfrA17–aadA5 being the most common. One of the strains (bla
CTX-M-14a-positive) harbored three class 1 integrons, and one of them was non-previously described containing as gene cassettes new
variants of aac(6′)-Ib and cmlA1 genes and it was linked to the bla
CTX-M-14a gene flanked by a truncated ISEcp1 sequence (included in GenBank with accession number JF701188). CTX-M-15-producing strains were ascribed to phylogroup B2
(six isolates) and D (six isolates). Multilocus-sequence-typing revealed ten different sequence-types (STs) among ESBL-positive
E.
coli strains with prevalence of ST405 (four strains of phylogroup D) and ST131 types (two strains of phylogroup B2 and serogroup
O25b). A high clonal diversity was also observed among studied strains by pulsed-field-gel-electrophoresis (11 unrelated profiles).
CTX-M-15 is an emergent mechanism of resistance in the studied hospital and the world-disseminated 0:25b-ST131-B2 and ST405-D
clones have been identified among CTX-M-15-producing isolates. 相似文献
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Sylvain Fisson Hanane Ouakrim Valérie Touitou Sylvie Baudet Rym Ben Abdelwahed Sabrina Donnou Amine Miloudi Claire Galand Bahram Bodaghi Phuc LeHoang Martine Brissard Magali Le Garff-Tavernier Wolf Herman Fridman Catherine Sautès-Fridman Nathalie Cassoux Hélène Merle-Béral 《PloS one》2013,8(2)
Primary intraocular lymphoma (PIOL), also called primary vitreoretinal lymphomas, often masquerades as uveitis. This misdiagnosis can result in subsequent brain involvement and oculocerebral lymphoma (OCL). In this study, we sought to characterize the helper T-cell type 1 (Th1)/Th2 cytokine profile in vitreous samples from patients with PIOL, OCL, uveitis and controls with non-inflammatory disease. Vitreous and aqueous humor samples from 87 patients with PIOL (n = 30), OCL (n = 12), uveitis (n = 34), and retinal detachment (RD) without hemorrhage (n = 11) were analyzed and their concentrations of interleukin (IL)-2, IL-4, IL-6, IL-10, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α were determined by flow cytometric bead arrays (CBA). The IL-10 levels determined by CBA were compared with those by ELISA. IL-10 concentrations measured by CBA and ELISA were highly correlated. IL-2, IL-4, and TNFα were not detected in any sample. The only cytokine detected at a significant level in samples from RD vitreous was IL-6. The IL-10/IL-6 ratio, as previously reported, was slightly higher in PIOL than in uveitis samples, but not for all patients. Cytokine profiles from PIOL and OCL samples did not differ. The combination of the IL-10/IL-6 and IL-10/IFNγ ratios was highly informative for discriminating PIOL/OCL from uveitis samples and for therapeutic follow up of PIOL. This strategy might be very helpful as an initial screening to rule out PIOL in patients thought to have uveitis. 相似文献
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