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Item Etude des Associations Symbiotiques de Retama monosperma : Approches Morphologique, Anatomique et Ultrastructurale, Caractérisation moléculaire des Isolats(University of sciences and technology in Oran, 2015-10-18) SELAMI NawelR. monosperma est une légumineuse arbustive capable d’établir une symbiose fixatrice d'azote avec des bactéries du sol, Rhizobia. Cette interaction aboutit à la formation de nodules au niveau du système racinaire de la plante. Comme l’étude de l’interaction symbiotique entre R. monosperma et les Rhizobia n’a pas été largement étudiée et Compte tenu du rôle primordial que joue cette espèce dans la bio-fertilisation et la stabilisation des dunes mobiles, nous nous sommes proposés dans la présente thèse d’établir la première étude détaillée de la morphologie et l’anatomie des nodules de R. monosperma. En effet, des nodules sauvages collectés des dunes côtières d’Oran, ont fait l’objet d’une (i) étude anatomique et ultrastructurale par microscopie photonique et électronique ; (ii) analyse génétique des microsymbiotes basée sur les séquences de gènes ARNr 16S, atpD, glnII et recA ; (iii) analyse de l’endoréduplication chez R. monosperma par cytométrie en flux. La caractérisation génétique des microsymbiotes de R. monosperma, indique que ces bactéries sont taxonomiquement très proche, voir identique aux microsymbiotes de R. sphaerocarpa récemment identifiés par Guerrouj et al. (2013), et nommée Bradyrhizobium retamae. L’étude anatomique et ultrastructurale révéle que les nodules de R. monosperma sont à croissance indéterminée, de type genistoide. Le cordon d’infection typique de la majorité des legumineuses est absent dans les nodules de R. monosperma et la diffusion de l’infection est assurée par la division des cellules nouvellement infectées. La zone fixatrice d’azote est homogène aux cellules complètement infectées et le réseau de cellules non envahi commun à la plupart des légumineuses est absent. De plus, le taux d’endoréduplication indispensable pour la différenciation des bactéroïdes dans les nodules indéterminés est trop faible voir nul dans les nodules de R. monosperma. En outre, plusieurs bactéries bénéfiques comme Methylobacterium et Pseudomonas koreensis ont été isolées à partir de nodules racinaires de R. monosperma. Dans cette étude, les premiers stades du processus de colonisation par Methylobacterium sp et P. koreensis, sont visualisés conjointement au microscope photonique et électronique. Des résultats préliminaires, témoignent clairement que P. koreensis et Methylobacterium sp se comportent comme bactéries endophytes associatives, qui peuvent nicher à l’intérieur des tissus de R. monosperma, sans lui induire de maladies symptomatiques.Item I n vivo antiinflammatory activity and chemical composition of H ypericum scabroides(University of sciences and technology in Oran, 2015-07-07) Mansour, SadiaTo evaluate the methanolic extracts of aerial parts of Hypericum scabroides (HSM) (200mg/kg, p.o.) for in vivo anti-inflammatory activity. Methods: The anti-inflammatory activity of HSM was tested in mice weighting (25+-5)g. Either vehicle (control group), the methanolic extracts (200 mg/kg) or diclofenac (50 mg/kg), was administered (p.o.) for 60 min before an edema was induced in the mice paw by subcutaneous injection of carrageenin. The mouse-paw volume was measured 1 h, 3h and 6 h after injection of carrageenin. Results: The HSM showed significant reduction of edema in carrageenan induced mice paw edema model at 1h and 3h for (78.03+-15.54)% *Corresponding author : Sadia Mansour , Phar macognos y, Api -Phyt ot er aphy Laboratory, Department of Biology, Faculty of SNV, Mostaganem University, Algeria. E-mail: mansoursadia@gmail.com Foundation Project: Supported by the Algerian Ministry of the Higher Education and Scientific Research, CNEPRU project approved in 2011/2013 (Grant No. F02220120001). and (40.44+-16.36)% , respectively. The diclofenac 50 mg/kg exhibited % reduction in paw volume (31.00+-11.52)% Aging, skin disorders, rheumatoid arthritis, atherosclerosis are caused by oxidative stress, occurring when production of reactive oxygen species(ROS)-in the form of hydroxyl radical, superoxide anion, peroxyl radical, singlet oxygen, hydrogen peroxi de or ozone, exceeds t he ant i oxi dant protective capacity of target cells Free radicals are the initiators of a redox reaction cascade, resulting in changes of the chemical structure of biological macromolecules, such as proteins, lipids and DNA , or disturbances of human cell metabolism [5][4], or even tissue injury Human skin is exposed to both external factors, such as radiation, smoking, pollutants, organic solvents, pesticides [6] and internal ROS products from normal cell metabolism, normal aerobic respiration, stimulated polymorphonuclear leukocytes or macrophages [8,9] , (0.80+-0.09)% and (9.39+-1.99)% after 1h, 3 h and 6 h, respectively compared to control group. The obtained results revealed that HSM has significant anti inflammatory activity. Furethermore, the chemical composition of HSM was analyzed by using high performance liquid chromatography–diode array dedector. The plant contained pseudohypericin (trace) hypericin (trace), chlorogenic acid (0.014 0+-0.000 5)% (0.005 0+-0.000 6)% , hyperoside (0.016+-0.005)% , isoquercitrin (0.034 0+-0.000 5)% and kaempferol (trace). Conclusions: The obtained results of the present investigation revealed that methanol extract of Hypericum scarbroides has significant anti-inflammatory activityItem Association of PTPN22 (rs2476601) and STAT4 (rs7574865) polymorphisms with rheumatoid arthritis in the Western Algerian population(University of sciences and technology in Oran, 2015-06-06) Fodil M; Benzaoui A; Zemani-Fodil F; Aberkane M; Boughrara W; Saidi-Mehtar N; Petit-Teixeira E; Boudjema AAim: The aim of the present study was to replicate the association of five risk gene polymorphisms (PTPN22- -rs2476601, STAT4-rs7574865, 6q23-rs6927172, IRF5-rs2004640 and TRAF1/C5-rs10818488) with RA in a specific population of the Western Algeria. Material and methods: The study group comprised 110 patients with RA and 197 ethnically matched heal thy control subjects. All polymorphisms were genotyped using predesigned TaqMan® assays. Allele and genotype frequencies in patients and control subjects were compared by chi-square test and odds ratios with 95% confidence intervals. Correction for multiple testing was carried out using the Bonferroni adjustment. Results: Statistically significant associations with RA were detected. The strongest signal was obtained for PTPN22-rs2476601 with an allelic Pvalue 3.32 x 10 (OR = 9.83, 95% CI [4.28 – 22.56]). A second significant association was obtained with STAT4-rs7574865 (allelic Pvalue = 4x10; OR = 1.75, 95% CI [1.16-2.63]).The third SNP, 6q23-rs6927172, showed a significant result of association with RA, but missed our criteria for significance at allelic level after Bonferroni’s correction (allelic Pvalue =0.027; OR =0.64,95% CI [0.42– 0.97]). Finally, IRF5-rs2004640 and TRAF1/C5-rs10818488 showed a significant association only at genotypic level (Pvalues: 3x10-3 and 2.9 x10-3-4 respectively) but did not reach statistical significance when comparing allele frequencies (Pvalues: 0.96 and 0.21 respectively). Conclusions: From this initial study, we can conclude that PTPN22-rs2476601 and STAT4-rs7574865 poly- -11 morphisms are clearly associated with the risk of RA in the Western Algerian population.Item Detection of CFTR mutations using PCR/ARMS in a sample of Algerian population(University of sciences and technology in Oran, 2015-06-01) Sediki, Fatima Zohra; Radoui, Abdelkarim; Cabet, Faiza; Zemani-Fodil, Faouzia; Saidi-Mehtar, Nadhira; Boudjema, AbdallahCystic fibrosis (CF) is the most common autosomal recessive disease in Caucasians. Wrongly considered as a European disease, CF is found in Algeria; but the literature data on the clinical profile and the spectrum of CFTR gene mutations are poor. In this study we investigate twenty-four unrelated Algerian families, with at least one child with CF. DNA extracts from blood samples of patients and parents were screened for CFTR gene mutations using Elucigene CF30 Kit which is based on a PCR/ARMS technique. Only five different mutations were identified. On the 48 alleles studied, most com- mon mutations were: c.1521_1523delCTT (F508del) 18.75%, c.579+1G>T (711+1G>T) 12.5%, c.1624G>T (G542X) 10.41%, c.3909C>G (N1303K) 4%, and c.1652G>A (G551D) 2%. The Elucigene CF30 kit highlights a portion of CFTR mutations in the Algerian population. It remains important for a first screening as it reveals the most common mutations. All this information is of interest for genetic testing and genetic counseling in Algeria and in European countries where immigration from the Maghreb is common.Item Impact of MTHFR rs1801133, MTHFR rs1801131 and ABCB1 rs1045642 polymorphisms with increased susceptibility of rheumatoid arthritis in the West Algerian population: a case-control study(University of sciences and technology in Oran, 2015-05-27) Boughrara W; Aberkane M; Fodil M; Benzaoui A; Dorgham S; Zemani F; Dahmani C; Petit Teixeira E; Boudjema ARheumatoid arthritis (RA) is an autoimmune disease that results in a chronic systemic inflammation. A few genetic epidemiologic studies found a potential association between genetic polymorphisms C677T (rs1801133) and A1298C (rs1801131) of methylenetatrahydrofolate reductase (MTHFR) gene and C3435T (rs1045642) of ATP-Binding cassette (ABCB1) gene and the increased risk for RA. The aim of this case-control study was to determine the relationship between these polymorphisms and RA susceptibility in West Algerian population. The dataset of the current study is composed of 110 RA patients and 101 healthy controls. All samples were genotyped for theses polymorphisms by TaqMan® allelic discrimination assay.Data were compared between cases and controls by the calculation of the odds ratio (OR) with a confidence interval at 95%. After age and RA erosion-stratified analyzes, no differences in genotypes or alleles frequencies distribution were found for MTHFR C677T (rs1801133) and ABCB1 C3435T (rs1045642) polymorphisms between RA cases and controls. However, the MTHFR A1298C (rs1801131) polymorphism presented a significant distribution in RA with age≥40 (Genotypic data: p=0.007, OR=13.53[1.44-63.31], Allelic data: p=0.001, OR=2.39[1.39-4.1]), and in RA erosive form (Genotypic data: p=0.002, OR=6.92[1.68-30.23], Al-lelic data: p=0.0001, OR=2.43[1.54-3.85]).These results were confirmed after the Bonferroni correction. In this study we have showed, for the first time in the West Algerian population, that the MTHFR A1298C (rs1801131) polymorphism can be associated with rheumatoid arthritis.Item Caractéristiques morpho-biométriques et systèmes d'élevage des poules locales en Algérie occidentale (Oranie)(University of sciences and technology in Oran, 2015-05-26) Mahammi, Fatima Zohra; Souheil Bachir Samir Gaouar; Nacera Tabet-Aoul; Michèle Tixier-Boichard; Nadhira Saïdi-MehtarDes enquetes ont ete menees dans 48 elevages repartis sur les 9 wilayas de la region de l’Oranie afin de caracteriser les populations de poules locales et leur mode d’elevage. Ces enquetes ont porte sur les caracteristiques des elevages (etat socio-economique de l’eleveur, mode d’elevage, reproduction et destination des produits d’elevage) et sur la description phenotypique de 334 poules locales. Les resultats montrent que les femmes sont les principales responsables des elevages avicoles et qu’elles utilisent le revenu modeste de ce type d’exploitations pour repondre a certaines charges domestiques. Les poules sont elevees dans des conditions mediocres et leur productivite est faible. Les mensurations corporelles considerees (poids corporel, longueur des pattes et des barbillons, diametre des pattes et hauteur des cretes) confirment le dimorphisme sexuel connu dans cette espece, avec des valeurs de poids corporel significativement plus elevees chez le male (1 817 297 g) que chez la femelle (1 335 227 g). Cette etude sera completee par une caracterisation genetique et moleculaire. Ainsi, l’association de l’information phenotypique et genetique et l’amelioration des conditions d’elevage pourront aider les eleveurs a ameliorer les performances de cette activite.Item Association des polymorphismes du gène méthylène-tétrahydrofolate réductase avec la leucémie myéloïde chronique(University of sciences and technology in Oran, 2015-04-28) Dorgham, Samia; Meriem Aberkane; Wefa Boughrara; Badra Antar Soltan; Nemra Mehalhal; Hadj TouhamiMethylene-tetrahydrofolate reductase (MTHFR) is a key enzyme of folate metabolism. Few studies were reported about its relationship with chronic myeloid leukemia (CML). We conducted a case-control study analyzing the prevalence of the polymorphisms MTHFR C677T and MTHFR A1298C in Algerians CML patients. Using TaqMan® allelic discrimination assay,we investigate MTHFR C677T and A1298C polymorphism distribution in 90 cases of CML and 100 healthy subjects. The frequencies of 677T alleles and genotypes 677TT and 677CT were significantly higher in cases than in control (P = 1E-6; OR= 6.77 [4.22-10.86]) and (P = 1E-6; OR= 10.38 [4.56-23.6]) respectively. Also, the frequencies of 1298C alleles and genotypes 1298CC and 1298AC were higher in cases (P = 9 E-6; OR= 2.65 [1.71-4.10]) and (P = 0.008; OR= 2.22 [1.21-4.06]) respectively. We report also the higher significance of the haplotype 677T/1298A and 677T/1298C in cases (P = 0.007; OR= 2.57 [1.26-5.24]) and (P = 5 E-6, OR= 6.91 [2.7646-17.2899]) respectively. Our results demonstrate that 677T and 1298C alleles are both associated with an increased risk of CML in Algeria.Item Molecular characterization and differentiation of five horse breeds raised in Algeria using polymorphic microsatellite markers(University of sciences and technology in Oran, 2015-03-15) Berber, Naima; S. Gaouar; G. Leroy; S. Kdidi; N. Tabet Aouel; N.Sa € ıdi MehtarIn this study, genetic analyses of diversity and differentiation were per- formed on five horse breeds raised in Algeria (Barb, Arab-Barb, Arabian, Thoroughbred and French Trotter). All microsatellite markers were highly polymorphic in all the breeds. A total of 123 alleles from 14 microsatellite loci were detected in 201 horses. The average number of alleles per locus was the highest in the Arab-Barb horses (7.86) and lowest in the thoroughbred breed (5.71), whereas the observed and expected heterozygosities per breed ranged from 0.71 (Thoroughbred) to 0.752 (Barb) and 0.71 (Thoroughbred) to 0.77 (Arab-Barb), respectively. The genetic differentiation between the breeds was significant (p < 0.01) based on the infinitesimal model (F ). Three different approaches for evaluating the genetic relationships were applied. Genetic distances, the factorial correspondence analysis and structure analysis showed that a significant amount of genetic variation is maintained in the native horse populations and the other breeds. The Barb and Arab-Barb breeds seem to be the most genetically related and support the decision to consider the breeds as same population.Item Impact of APOE gene polymorphisms on the lipid profile in an Algerian population(University of sciences and technology on Oran, 2015-02-24) Houssam, Boulenouar; Mediene Benchekor, Sounnia; Naïma Meroufel, Djabaria; Lardjam Hetraf, Sarah Aicha; Ouhaibi Djellouli, Hadjira; Xavier Hermant; Benjamin Grenier-Boley; Imane Hamani Medjaoui; Nadhira Saidi Mehtar; Philippe Amouyel; Leila Houti; Aline Meirhaeghe; Louisa GoumidiBackground: The importance of apolipoprotein E (APOE) in lipid and lipoprotein metabolism is well established. However, the impact of APOE polymorphisms has never been investigated in an Algerian population. This study assessed, for the fist time, the relationships between three APOE polymorphisms (epsilon, rs439401, rs4420638) and plasma lipid concentrations in a general population sample from Algeria. Methods: The association analysis was performed in the ISOR study, a representative sample of the population living in Oran (787 subjects aged between 30 and 64). Polymorphisms were considered both individually and as haplotypes. Results: In the ISOR sample, APOE ε4 allele carriers had higher plasma triglyceride (p=0.0002), total cholesterol (p=0.009) and LDL-cholesterol (p=0.003) levels than ε3 allele carriers. No significant associations were detected for the rs4420638 and rs439401 SNPs. Linkage disequilibrium and haplotype analyses confirmed the respectively deleterious and protective impacts of the ε4 and ε2 alleles on LDL-cholesterol levels and showed that the G allele of the rs4420638 polymorphism may exert a protective effect on LDL-cholesterol levels in subjects bearing the APOE epsilon 4 allele. Conclusion: Our results showed that (i) the APOE epsilon polymorphism has the expected impact on the plasma lipid profile and (ii) the rs4420638 G allele may counterbalance the deleterious effect of the ε4 allele on LDL-cholesterol levels in an Algerian population.Item polymorphisms and the risk of colorectal cancer in West Algerian population: a case–control study(Université des Sciences et de la Technologie D’Oran Mohamed Boudiaf, 2014) Fatima Zohra, MoghtitAbstract Colorectal cancer (CRC) is a complex and multifactorial disease, in which genetic and environmental factors both seem to play a part. Many epidemiological studies have explored the association between genetic polymorphisms of X-ray repair cross-complementing group 3 (XRCC3) (Thr241Met) and Xeroderma pigmentosum group D (XPD) lysine to glutamine at codon 751 (Lys751Gln) and risk of CRC in various populations; however, the results are controversial. We conducted this case–control study in a West Algerian population to assess the potential role of this genetic polymorphism on the risk of CRC in this population. Genomic DNA was extracted from blood samples collected from 129 sporadic CRC patients and 148 normal controls. The polymorphisms were determined by pyrosequencing technique. The distribution of XRCC3 Thr241Met and XPD Lys751Gln genotypes among controls did not differ significantly from those predicted by the Hardy–Weinberg distribution (p [0.05). There were no significant differences in the genotypes distribution and allele frequencies between CRC patients and controls. A significant association was found between the combined heterozygous of XRCC3 and homozygous variant of XPDgene and CRC. This is the first study on DNA repair genetic polymorphisms in West Algerian population, and it suggests that the XRCC3 Thr241Met and XPD Lys751Gln polymorphisms may not be associated with the CRC risk in this population.