The contribution of the candidate gene CTLA4 to type 1 diabetes is not well established. Although several polymorphisms have been repeatedly associated to the disease, several studies have not confirmed the association. The joint analysis of three SNPs in the CTLA4 promoter region (À1722, À1661, and À319), one SNP in the first exon (+49), and one dinucleotide repeat in the 3 0 untranslated region, in a case-control study in a North African population, shows a strong association of the CTLA4 region with the disease. The À1661G allele showed a significant association with an odds ratio of 2.13. Moreover, the internal structure of the dinucleotide repeat has been deeply analyzed. The present results reveal the importance of polymorphisms in the CTLA4 promoter region, their probable role in gene expression and, ultimately, their relation to the etiology of type 1 diabetes. Previous contradictory association studies might be due to the effect of linkage disequilibrium between the polymorphism analyzed and the alteration within the CTLA4 region. This alteration may be different depending on the genetic background of the population. The present work stresses the need to perform exhaustive analysis of the promoter region polymorphisms in order to detect association with the disease.

The contribution of single nucleotide polymorphisms in tumor necrosis factors (TNF) alpha and beta to autoimmune diseases, and to type 1 diabetes mellitus (T1DM) in particular, is not well established, and may be confounded by linkage disequilibrium to class II HLA genes. At least two polymorphisms seem to have functional relevance in the respective genes: TNFA-307 and TNFB+252. We have typed these two polymporphisms in samples of Moroccan T1DM patients and controls for which class II HLA genes had already been typed. Tumor necrosis factors and compound TNF-class II HLA haplotypes were inferred; it was the first time that such a design had been implemented. Independent of linkage disequilibrium with class II HLA, TNF haplotype TNFA-307*2 - TNFB+252*2 showed a significant protective effect (OR = 0.031), partly exacerbated by partial linkage to protective class II haplotypes. Such effect could be detected because Morocco shows the highest frequency of the TNFA-307*2 allele yet reported. This highlights the possible population differences in alleles contributing to autoimmune diseases.

No abstract

No abstract

Around the world, the increasing population and consumption are placing huge demands on food. Agriculture is considered one of the important sectors in the world and the force to feed humanity. While under these circumstances, which stand out by successive years of drought, degradation of soil, climate change, and global warming, this sector has multifaceted a major issue that goes beyond threatening food security. Thus, Morocco characterized by an arid and semi-arid climate is one example of countries that suffered from those problems. Due to lack of rain, the water resources of some Moroccan arable lands are consumed highly as well as the quality of its soils is now degraded. This issue calls for new approaches to amending the degraded soils in these regions and sustain water supplies. Indeed, biochar can be a remedy for these poor soils; in fact, it has an incredible sequester carbon on soil, a benefit on the environment as well as on plant growth. Despite its virtues, certain biochars contain phytotoxic compounds. In this study, four biochars prepared from banana waste, peanut hull, almond shells, and walnut shells were tested on three plant species (cress to test (HAP), barley for assessing heavy metals, and lettuce to assess salinity) before any field application. The chemical and physical analysis was done for the four biochars and the sandy soil, the four biochars were also analyzed by scanning electron microscopy (SEM) for identifying the morphology of each biochar. The results showed that the four biochars enhanced water holding capacity (WHC), they also revealed the existence of heavy metals especially for almond shells biochar and walnut shells biochar. While for the morphology of each biochar, banana waste biochar (BC-BW) and peanut hull biochar (BC-PeH) had more pores than almond shells biochar (BC-Alm) and walnut shells biochar(BC-WS). Concerning the phytotoxic tests, the lettuce was germinated in all biochars treatments except for the 8% biochar banana treatment, for the cress and barley, all the treatments were grown.