Apolipoprotein B (apo B) is the major protein component of LDL, VLDL and chylomicrons. Numerous polymorphisms of the apolipoprotein B gene have been described. Particularly, the insertion/deletion polymorphism located in the coding part of the signal peptide of apo B, associated with modification of lipid concentrations and the risk of cardiovascular disease, has been reported in the general population. No such study in the Tunisian population has been performed. The aim of our study was to assess the effect of insertion/deletion polymorphism of the apolipoprotein B gene on lipid levels in a sample of the Tunisian population. A total of 458 unrelated subjects (321 men and 137 women) were included. The insertion/deletion polymorphism was determined by electrophoresis on polyacrylamide gels after PCR amplification. The relative frequencies of the Ins and Del alleles were 0.74 and 0.26, respectively. These frequencies were similar to those found in other Caucasian populations. There was no significant difference in serum TC, TG, and HDL-C levels due to the influence of the genotypes. However, significant variation among the three genotypes was seen for LDL-cholesterol (p<0.001) and apo B (p<0.001) levels. Individuals homozygous for the Del allele had higher levels than individuals homozygous for the Ins allele, while individuals heterozygous for both alleles exhibited intermediate levels. When the data were analyzed in men and women separately, a similar effect was seen in both groups. Our results show that distribution of apo B insertion/deletion polymorphism in Tunisians is similar to other Caucasian population and confirm the reported association with serum LDL-cholesterol and apo B concentrations., A. Kallel, M. Fekl, M. Elasmi, M. Souissi, H. Shanhaji, S. Omar, S. Haj Taieb, R. Jemaa, N. Kaabachi., and Obsahuje bibliografii a bibliografické odkazy
The response of tomato (Solanum lycopersicum L.) to abiotic stress has been widely investigated. Recent physiological studies focus on the use of osmoprotectants to ameliorate stress damage, but experiments at a field level are scarce. Two tomato cultivars were used for an experiment with saline water (6.57 dS m-1) and subsurface drip irrigation (SDI) in a silty clay soil. Rio Grande is a salinity-tolerant cultivar, while Heinz-2274 is the salt-sensitive cultivar. Exogenous application of proline was done by foliar spray at two concentrations (10 and 20 mg L-1) during the flowering stage. Control plants were treated with saline water without proline. Proline at the lower concentration (10 mg L-1) increased dry mass of different plant organs (leaves, stems, and roots) and it improved various chlorophyll a fluorescence parameters compared with controls. Regarding mineral nutrition, K+ and P were higher in different organs, while low accumulation of Na+ occurred. However, Mg2+ was very high in all tissues of Rio Grande at the higher concentration of proline applied. Thus, the foliar spray of proline at 10 mg L-1 increased the tolerance of both cultivars. The growth of aboveground biomass of Heinz-2274 was enhanced by 63.5%, while Rio Grande improved only by 38.9%., B. Kahlaoui, M. Hachicha, S. Rejeb, M. N. Rejeb, B. Hanchi, E. Misle., and Obsahuje bibliografii