Identification of genetic defects underlying FVII deficiency in 10 patients belonging to eight unrelated families of the North provinces from Tunisia

ABSTRACT: Inherited factor VII (FVII) deficiency is a rare disorder characterized by a bleeding phenotype varying from mild to severe. To date, more than 200 mutations have been described along the F7 gene encoding for FVII. The aim of this study was the identification of genetic defects underlying FVII deficiency in 10 patients belonging to eight unrelated families of the North provinces from Tunisia. Mutation detection was performed by sequencing the whole F7 gene coding region, exon-intron boundaries and about 400 bp of the promoter region. We identified 5 mutations in five unrelated families; the novel p.F328Y mutation and the reported mutations: p.R304Q, p.M298I, IVS1aG > A and nt1005C > T. For the remaining 5 patients we didn't identified any mutations using PCR/Sequencing protocol. In conclusion, this study represents the first comprehensive molecular series of FVII deficiency affected patients in Tunisia from the North. We will try in the future to continue the molecular study for Tunisian patients from Center and South provinces in order to have a complete idea about the FVII deficiency mutational profile in our country. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1288044089753085.     

Structural evidence for the order of preference of inorganic substrates in mammalian heme peroxidases: crystal structure of the complex of lactoperoxidase with four inorganic substrates,SCN-, I-, Br– and Cl-

Lactoperoxidase (LPO) is a member of the family of mammalian heme peroxidases. It catalyzes the oxidation of halides and pseudohalides in presence of hydrogen peroxide. LPO has been co-crystallized with inorganic substrates, SCN^-, I^-, Br^- and Cl^-. The structure determination of the complex of LPO with above four substrates showed that all of them occupied distinct positions in the substrate binding site on the distal heme side. The bound substrate ions were separated from each other by one or more water molecules. The heme iron is coordinated to His-351 N^ϵ2 on the proximal side while it is coordinated to conserved water molecule W-1 on the distal heme side. W-1 is hydrogen bonded to Br^- ion which is followed by Cl^- ion with a hydrogen bonded water molecule W-5′ between them. Next to Cl^- ion is a hydrogen bonded water molecule W-7′ which in turn is hydrogen bonded to W-8′ and N atom of SCN^-. W-80 is hydrogen bonded to W-9′ which is hydrogen bonded to I^-. SCN^- ion also interacts directly with Asn-230 and through water molecules with Ser-235 and Phe-254. Therefore, according to the locations of four substrate anions, the order of preference for binding to lactoperoxidase is observed as Br^- > Cl^- > SCN^- > I^-. The positions of anions are further defined in terms of subsites where Br^- is located in subsite 1, Cl^- in subsite 2, SCN^- in subsite 3 and I^- in subsite 4.     

Evaluation of Efficiency of Modified Polypropylenimine (PPI) with Alkyl Chains as Non-viral Vectors Used in Co-delivery of Doxorubicin and TRAIL Plasmid

In this study, co-delivery system was achieved via plasmid encoding TNF related apoptosis inducing ligand (pTRAIL) and doxorubicin (DOX) using carrier based on polypropylenimine (PPI) modified with 10-bromodecanoic acid. Incorporation of alkylcarboxylate chain to PPIs (G4 and G5) could improve transfection efficiency via overcoming the plasma membrane barrier of the cells and decrease cytotoxicity of PPI. Characterization of fabricated NPs revealed that PPI G5 in which 30% of primary amines were substituted by alkyl carboxylate chain (PPI G5-Alkyl 30%) has higher drug loading as compared to the other formulations. PPI G5-Alkyl 30% indicated a decreased drug release may be due to alkyl chains on the surface of PPI, which serve as an additional hindrance for drug diffusion. In vitro cytotoxicity experiments demonstrated that co-delivery system induced apoptosis of tumor cells more efficiently than each of delivery system alone. Furthermore, these results revealed that our combined delivery platform of pTRAIL and DOX using Alkyl-modified PPI G5 can significantly improve the anti-tumor activity and this strategy might develop a new therapeutic window for cancer treatment.