HLA-A, -B, -DR and -DQ allele and haplotype frequencies in the Moroccan population: a general population study

PURPOSE OF STUDY: The aim of this general population study is to extend our knowledge about the HLA-A, -B, -DR and -DQ genes distribution and their diversity among the Moroccan population. PATIENTS AND METHODS: One hundred and ten unrelated healthy Moroccans from diverse regions of the country were included in the study. HLA typing was done either by serological (standard complement dependent microlymphocytotoxicity) and/or molecular (sequence-specific primer amplification) techniques. RESULTS: The most frequent alleles observed were: HLA-A2 (19.1%), -A1 (10%), -A3 (10%), -B44 (9.6%), -DR3 (17.1%), -DR4 (15.3%), -DQ2 (30.6%), -DQ6 (26.4%) and -DQ3 (25%). No predominant haplotype was observed for HLA A-B while high frequency was observed for some HLA DR-DQ associations (DR3-DQ2, DR15-DQ6, DR7-DQ2, DR4-DQ3, DR13-DQ6). Comparison with neighbouring populations, on the basis of alleles, haplotypes and genetic distances, showed that Moroccan population is close to the Algerians, the Tunisians, the Spaniards and the French. The haplotype frequencies revealed also relationships with Italians, Sardinians, Basques, Portuguese and Moroccan Jews populations. CONCLUSION: Our results confirm and extend the current knowledge about the Moroccan genetic pattern and reflect all the ethnic diversity of the country. This study will be helpful in the future for clinical analysis like transplantation and HLA-associated diseases in Moroccan population.     

Coronary extraction and characterization in multi-detector computed tomography

The last technological advances of multi-detector computed tomography (MDCT) have brought significant improvements in image quality and consequently diagnostic performance. It opens, in particular, new perspectives for the coronary artery disease assessment. This paper presents a method for the coronary artery extraction and the lesion quantification. It makes use of a two stage-process. A tracking algorithm of the vascular structure, based on a 3D geometric moment operator, is first applied to estimate the vessel central axis location and its local diameter. It led to the extraction of the overall coronary tree. A deformable model technique, using a modified version of 3D level set technique, is then run on pathological vascular segments to refine the delineation of the wall and parietal calcifications. Parameters such as the narrowing or enlargement ratio of the vascular lumen, the minimum/maximum areas and the percent-area stenosis or aneurysm, are then computed for diagnosis purpose. The first method was submitted to a clinical evaluation on six data sets that showed good sensitivity and specificity performances. The second one was validated by experts, through a visual inspection of 2D cross-sections and volume rendering.     

Deep brain stimulation for Parkinson''s disease: electropermeabilization and activation

Deep brain stimulation, DBS, is an accepted technique for the treatment of Parkinson's disease. DBS affects the electrical functions of neurons, but exactly how it alters those functions is not clearly explained. An electrical model is determined to simulate treatment with DBS of the sub thalamic nucleus. This model shows the difference in electrical fields between the inside and the outside the neurons. The generated electrical field near the electrodes is high enough to perform an electropermeabilization of the cell membranes, which most likely blockade normal nerve pulses or reduce the nerve impulse speed. Further away from the electrodes activation of large axons is performed.     

Analysis of plantar pressure in diabetic type 2 subjects with and without neuropathy

Diabetes is a disorder of metabolism—the way our bodies use digested food for growth and energy. The most common form of diabetes is type 2 diabetes. Abnormal plantar pressures are considered to play a major role in the pathologies of neuropathic ulcers in the diabetic foot. The purpose of this study was to examine the plantar pressure distribution in normal, diabetic type 2 with and without neuropathy subjects. Footscans were obtained using the F-Scan (Tekscan USA) in-shoe pressure measurement system. Various pedobarographic parameters such as the total plantar force, total contact area, peak pressures, percentage medial impulse (PMI), load and power ratio (PR, the ratio of high frequency power to the total power in an image) were evaluated. These parameters were subjected to ANOVA (analysis of variance) test with more than 95% confidence interval giving excellent P-values in all the categories.