排序方式: 共有92条查询结果,搜索用时 15 毫秒
41.
Soumaya Arraouadi Mounawer Badri Cheruth Abdul Jaleel Naceur Djébali Houcine Ilahi Thierry Huguet Mohamed Elarbi Aouani 《Tropical plant biology》2009,2(3-4):122-132
We used 19 quantitative traits and 14 microsatellite markers (SSRs) to analyze the genetic variation in four natural populations of the model legume Medicago truncatula sampled in southern Tunisia. The greatest genetic variation of quantitative traits and molecular markers occurred within populations (>71%). In contrast to quantitative population differentiation (Q ST ?=?0.09), a high level of molecular differentiation (F ST ?=?0.23) was found among populations. The majority of quantitative traits exhibited Q ST values significantly less than F ST values, suggesting that selection may be acting to suppress differentiation for these traits. There was no significant correlation between genetic variation of quantitative traits and molecular markers within populations. On the other hand, significant correlations were found between measured quantitative characters and the site-of-origin environmental factors. The eco-geographical factors with the greatest influence on the variation of measured traits among populations were altitude, followed by soil texture, assimilated phosphorus (P2O5) and organic matter. Nevertheless, there were no consistent patterns of associations between gene diversity (He) and eco-geographical factors. 相似文献
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Cheikh-Ali Soumaya Farman Muhammad Lacaille-Dubois Marie-Aleth Semmar Nabil 《Phytochemistry Reviews》2019,18(2):405-441
Phytochemistry Reviews - Saponins in Caryophyllaceae were subjected to many structural elucidations for several decades leading to big datasets of molecules essentially based on four aglycones:... 相似文献
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S Thomas M Legendre S Saunier B Bessières C Alby M Bonnière A Toutain L Loeuillet K Szymanska F Jossic D Gaillard MT Yacoubi S Mougou-Zerelli A David MA Barthez Y Ville C Bole-Feysot P Nitschke S Lyonnet A Munnich CA Johnson F Encha-Razavi V Cormier-Daire C Thauvin-Robinet M Vekemans T Attié-Bitach 《American journal of human genetics》2012,91(2):372-378
Orofaciodigital syndromes (OFDSs) consist of a group of heterogeneous disorders characterized by abnormalities in the oral cavity, face, and digits and associated phenotypic abnormalities that lead to the delineation of 13 OFDS subtypes. Here, by a combined approach of homozygozity mapping and exome ciliary sequencing, we identified truncating TCTN3 mutations as the cause of an extreme form of OFD associated with bone dysplasia, tibial defect, cystic kidneys, and brain anomalies (OFD IV, Mohr-Majewski syndrome). Analysis of 184 individuals with various ciliopathies (OFD, Meckel, Joubert, and short rib polydactyly syndromes) led us to identify four additional truncating TCTN3 mutations in unrelated fetal cases with overlapping Meckel and OFD IV syndromes and one homozygous missense mutation in a family with Joubert syndrome. By exploring roles of TCTN3 in human ciliary related functions, we found that TCTN3 is necessary for transduction of the sonic hedgehog (SHH) signaling pathway, as revealed by abnormal processing of GLI3 in patient cells. These results are consistent with the suggested role of its murine ortholog, which forms a complex at the ciliary transition zone with TCTN1 and TCTN2, both of which are also implicated in the transduction of SHH signaling. Overall, our data show the involvement of the transition zone protein TCTN3 in the regulation of the key SHH signaling pathway and that its disruption causes a severe form of ciliopathy, combining features of Meckel and OFD IV syndromes. 相似文献
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B Kitab A Essaid El Feydi R Afifi C Trepo M Benazzouz W Essamri F Zoulim I Chemin HS Alj S Ezzikouri S Benjelloun 《PloS one》2012,7(8):e42891
Background
Hepatitis B virus (HBV) is one of the most common human pathogens that cause aggressive hepatitis and advanced liver disease (AdLD), including liver cirrhosis and Hepatocellular Carcinoma. The persistence of active HBV replication and liver damage after the loss of hepatitis B e antigen (HBeAg) has been frequently associated with mutations in the pre-core (pre-C) and core promoter (CP) regions of HBV genome that abolish or reduce HBeAg expression. The purpose of this study was to assess the prevalence of pre-C and CP mutations and their impact on the subsequent course of liver disease in Morocco.Methods/Principal Findings
A cohort of 186 patients with HBeAg-negative chronic HBV infection was studied (81 inactive carriers, 69 with active chronic hepatitis, 36 with AdLD). Pre-C and CP mutations were analyzed by PCR-direct sequencing method. The pre-C stop codon G1896A mutation was the most frequent (83.9%) and was associated with a lower risk of AdLD development (OR, 0.4; 95% CI, 0.15–1.04; p = 0.04). HBV-DNA levels in patients with G1896A were not significantly different from the other patients carrying wild-type strains (p = 0.84). CP mutations C1653T, T1753V, A1762T/G1764A, and C1766T/T1768A were associated with higher HBV-DNA level and increased liver disease severity. Multiple logistic regression analysis showed that older age (≥40 years), male sex, high viral load (>4.3 log10 IU/mL) and CP mutations C1653T, T1753V, A1762T/G1764A, and C1766T/T1768A were independent risk factors for AdLD development. Combination of these mutations was significantly associated with AdLD (OR, 7.52; 95% CI, 4.8–8; p<0.0001).Conclusions
This study shows for the first time the association of HBV viral load and CP mutations with the severity of liver disease in Moroccan HBV chronic carriers. The examination of CP mutations alone or in combination could be helpful for prediction of the clinical outcome. 相似文献47.
Soumaya Marzouki Maha Abdeladhim Chaouki Ben Abdessalem Fabiano Oliveira Beya Ferjani Dana Gilmore Hechmi Louzir Jesus G. Valenzuela Mélika Ben Ahmed 《PLoS neglected tropical diseases》2012,6(11)
Background
Zoonotic cutaneous leishmaniasis (ZCL) due to Leishmania major is highly prevalent in Tunisia and is transmitted by a hematophagous vector Phlebotomus papatasi (P. papatasi). While probing for a blood meal, the sand fly injects saliva into the host''s skin, which contains a variety of compounds that are highly immunogenic. We recently showed that the presence of anti-saliva antibodies was associated with an enhanced risk for leishmaniasis and identified the immunodominant salivary protein of Phlebotomus papatasi as a protein of approximately 30 kDa.Methodology/Principal Findings
We cloned and expressed in mammalian cells two salivary proteins PpSP30 and PpSP32 with predicted molecular weights close to 30 kDa from the Tunisian strain of P. papatasi. The two recombinant salivary proteins were purified by two-step HPLC (High-Performance Liquid Chromatography) and tested if these proteins correspond to the immunodominant antigen of 30 kDa previously shown to be recognized by human sera from endemic areas for ZCL and exposed naturally to P. papatasi bites. While recombinant PpSP30 (rPpSP30) was poorly recognized by human sera from endemic areas for ZCL, rPpSP32 was strongly recognized by the tested sera. The binding of human IgG antibodies to native PpSP32 was inhibited by the addition of rPpSP32. Consistently, experiments in mice showed that PpSP32 induced the highest levels of antibodies compared to other P. papatasi salivary molecules while PpSP30 did not induce any detectable levels of antibodies.Conclusions
Our findings demonstrate that PpSP32 is the immunodominant target of the antibody response to P. papatasi saliva. They also indicate that the recombinant form of PpSP32 is similar to the native one and represents a good candidate for large scale testing of human exposure to P. papatasi bites and perhaps for assessing the risk of contracting the disease. 相似文献48.
Badra Bouamama Asma Ben Salem Fatma Ben Youssef Soumaya Chaieb Mohamed-Hbib Jaafoura Ahmed Mliki Abdelwahed Ghorbel 《In vitro cellular & developmental biology. Plant》2011,47(2):321-327
The regeneration ability of a Tunisian barley accession originated from Kerkena islands was monitored through somatic embryogenesis
and organogenesis. To prevent or to reduce normal germination, longitudinally bisected as well as base-wounded mature caryopses
were cultured on a modified Chée and Pool-based medium (CP) enriched with different phytohormonal combinations. The greatest
embryogenesis response was obtained when base-wounded caryopses were cultured on CP enriched with 2 mg/l chlorophenoxyacetic
acid + 2.5 mg/l kinetin (76.85%). The same combination coupled to longitudinally bisected caryopses led to the embryogenic
induction at the hypocotyl base of the germinated caryopses (61.9%). Embryogenic calluses differentiated into globular, heart-shaped,
torpedo, and fully differentiated stages of somatic embryos on hormone-free Murashige and Skoog-based medium. Rooted plantlets
were successfully transferred to soil and grown to maturity in the greenhouse and produced fertile seeds within 3 mo. On the
other hand, organogenesis was achieved on CP enriched with 2 mg/l 2,4-dichlorophenoxyacetic acid + 2.5 mg/l kinetin. Histological
aspects and scanning electron microscopy of both regeneration methods confirmed further the embryogenic and organogenic nature
of the established processes. This efficient plant regeneration system provides a foundation for generating transgenic plants
and germplasm preservation of “Kerkena” barley accession. 相似文献
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Sayeh Ezzikouri Rhimou Alaoui Khadija Rebbani Ikram Brahim Fatima-Zohra Fakhir Salwa Nadir Helmut Diepolder Salim I. Khakoo Mark Thursz Soumaya Benjelloun 《PloS one》2013,8(1)
Background
Genetic variation in the IL28B gene has been strongly associated with treatment outcomes, spontaneous clearance and progression of the hepatitis C virus infection (HCV). The aim of the present study was to investigate the role of polymorphisms at this locus with progression and outcome of HCV infection in a Moroccan population.Methods
We analyzed a cohort of 438 individuals among them 232 patients with persistent HCV infection, of whom 115 patients had mild chronic hepatitis and 117 had advanced liver disease (cirrhosis and hepatocellular carcinoma), 68 individuals who had naturally cleared HCV and 138 healthy subjects. The IL28B SNPs rs12979860 and rs8099917 were genotyped using a TaqMan 5′ allelic discrimination assay.Results
The protective rs12979860-C and rs8099917-T alleles were more common in subjects with spontaneous clearance (77.9% vs 55.2%; p = 0.00001 and 95.6% vs 83.2%; p = 0.0025, respectively). Individuals with clearance were 4.69 (95% CI, 1.99–11.07) times more likely to have the C/C genotype for rs12979860 polymorphism (p = 0.0017) and 3.55 (95% CI, 0.19–66.89) times more likely to have the T/T genotype at rs8099917. Patients with advanced liver disease carried the rs12979860-T/T genotype more frequently than patients with mild chronic hepatitis C (OR = 1.89; 95% CI, 0.99–3.61; p = 0.0532) and this risk was even more pronounced when we compared them with healthy controls (OR = 4.27; 95% CI, 2.08–8.76; p = 0.0005). The rs8099917-G allele was also associated with advanced liver disease (OR = 2.34; 95% CI, 1.40–3.93; p = 0.0100).Conclusions
In the Moroccan population, polymorphisms near the IL28B gene play a role both in spontaneous clearance and progression of HCV infection. 相似文献50.
Nicole Abreu Soumaya Mannoubi Ertan Ozyamak David Pignol Nicolas Ginet Arash Komeili 《Journal of bacteriology》2014,196(17):3111-3121
Many bacterial species contain multiple actin-like proteins tasked with the execution of crucial cell biological functions. MamK, an actin-like protein found in magnetotactic bacteria, is important in organizing magnetosome organelles into chains that are used for navigation along geomagnetic fields. MamK and numerous other magnetosome formation factors are encoded by a genetic island termed the magnetosome island. Unlike most magnetotactic bacteria, Magnetospirillum magneticum AMB-1 (AMB-1) contains a second island of magnetosome-related genes that was named the magnetosome islet. A homologous copy of mamK, mamK-like, resides within this islet and encodes a protein capable of filament formation in vitro. Previous work had shown that mamK-like is expressed in vivo, but its function, if any, had remained unknown. Though MamK-like is highly similar to MamK, it contains a mutation that in MamK and other actins blocks ATPase activity in vitro and filament dynamics in vivo. Here, using genetic analysis, we demonstrate that mamK-like has an in vivo role in assisting organelle alignment. In addition, MamK-like forms filaments in vivo in a manner that is dependent on the presence of MamK and the two proteins interact in a yeast two-hybrid assay. Surprisingly, despite the ATPase active-site mutation, MamK-like is capable of ATP hydrolysis in vitro and promotes MamK filament turnover in vivo. Taken together, these experiments suggest that direct interactions between MamK and MamK-like contribute to magnetosome alignment in AMB-1. 相似文献