Robust sensorless vector control of an induction machine using Multiobjective Adaptive Fuzzy Luenberger Observer.

This paper presents an inherent speed estimation scheme associated to the Indirect Field Oriented Control in case of Induction motor sensorless control. Indeed, through the design of a Multiobjective Adaptive Fuzzy Luenberger Observer, the speed sensorless control issue even at low speed, the observer poles' assignment issues and the speed estimation's sensitivity to rotor resistance uncertainties issue are treated concurrently. First of all, the structure of the proposed Takagi-Sugeno adaptive observer is described. Secondly, based on Lyapunov theory, observer gains are designed and a fuzzy speed estimation scheme is provided. The design's objectives consist of minimizing the sensitivity of the proposed observer to rotor resistance uncertainties (using the L2 techniques) and to guarantee a specified observer dynamic performances through a D-stability analysis. The design conditions are formulated into Linear Matrix Inequalities terms. Finally, experiments are conducted to demonstrate the effectiveness of the proposed results regardless of uncertainties in the rotor resistance.

[Prenatal diagnosis of a giant cystic lymphangioma in the axillothoracic wall]. / Diagnostic anténatal d'un lymphangiome kystique géant de la paroi thoraco-axillaire.

Cystic lymphangiomas are benign malformative tumors of the lymphatic vessels, rare but potentially serious and usually located in the cervical region. The diagnosis is usually easy, but the treatment is sometimes difficult because of their location and extension into the surrounding tissue. We report a case of giant cystic lymphangioma of the right axillary-thoracic wall diagnosed by prenatal ultrasound at 20 weeks gestation. The male infant was born at 37 weeks gestation with a large, swelling, lateral parietal right chest. Ultrasound soft tissue and chest CT scan confirmed the diagnosis of giant cystic lymphangioma of the right axillary-thoracic wall. Surgical excision was performed on the 21st day after birth and the mass was excised incompletely. The postoperative course was uncomplicated. Ultrasound soft tissue follow-up showed the persistence of multiple cystic structures in the axilla. Prenatal diagnosis of these tumors is essential for planning multidisciplinary management in early postnatal care.

[Management and follow-up of antenatally diagnosed primary megaureters]. / Prise en charge et évolution des méga-uretères primitifs de découverte anténatale.

INTRODUCTION AND OBJECTIVES: To study the diagnostic and outcome aspects of antenatally diagnosed primary megaureters and analyse the results of the postnatal medicochirurgical management. PATIENTS AND METHODS: The authors report a retrospective analysis of 12 patients been born between 1998 and 2009 with primary megaureter antenatally diagnosed between 20 and 32weeks of gestation. A postnatal radiological assessment comprising urinary tract ultrasound, DTPA or MAG3 renal scintigraphy, retrograde cystography, DMSA renal scintigraphy and intravenous urography was performed. All the patients were put under urinary antiseptic treatment and followed since the birth. RESULTS: This study comprised nine boys and three girls, all been born at term with normal trophicity. Mean age of antenatal diagnosis of hydronephrosis was 26weeks of gestation. Mean age of definitive postnatal diagnosis was ten months. Left megaureter was seen in five children, right in two cases and five patients had bilateral megaureter comprising a total of 17 renal units of which eight units were non-obstructed/non-refluxing, three units were refluxing, five units were obstructed and one unit was obstructed and refluxing. Megaureter was associated to controlateral ureteropelvic junction obstruction syndrome in one patient and to ipsilateral ureteral duplicity with a superior polar kidney in another case. Renal function was less than 20% in four renal units. The mean follow-up was four years (range : 10months to 11years). Outcome was marked by urinary infections in seven cases of which four patients had non-obstructed/non-refluxing megaureter. Six patients required surgical correction, two for non-obstructed/non-refluxing megaureter complicated with urinary recurring infections, three for obstructed megaureter with severe renal functional deterioration and one patient for bilateral refluxing megaureter grade V. Two other patients required surgical treatment, one for controlateral ureteropelvic junction obstruction syndrome and the other for ipsilateral ureteral duplicity with destroyed superior polar kidney. Mean age at surgery was 22,6months (range : 6 months to 7 years). CONCLUSION: Half of our patients with antenatal diagnosis of primary megaureter required surgical correction. Urinary recurring infections, renal functional deterioration less than 20% and importance of ureteral dilatation with vesico-ureteric reflux grade V were predictive factors for surgery.

Prenatal diagnosis and prognosis of triple X syndrome: 47, XXX.

Triple X syndrome is a relatively common sex chromosomal abnormality occurring in 0,1% of live-born female infants. Most of these infants have a normal phenotype and only a few cases with 47, XXX karyotype have congenital malformations. We report three cases of triple X syndrome that were diagnosed prenatally by genetic amniocentesis for advanced maternal age and have been observed from birth to age of 3 to 12 years. A description of their growth and development is presented. The birth weight was normal in all patients and one of them had facial dysmorphism with right microphtalmia and auricular septal defect. During the first 2 years of life, the neuromotor development of these infants was not distinguishable from chromosomally normal children. By 3 years of age, two patients have a moderate developmental delay in speech and language. One girl 12-year-old had normal schooling. The diagnosis of the triple X syndrome can be never made because clinical demonstrations are not rather important to arouse the demand of a karyotype. Prenatal diagnosis is often made in front of the advanced maternal age. Expectant parents must be counseled as to the significance of this 47, XXX karyotype and prognostic information must be given.

[Imaging features of Takayasu's arteritis]. / Imagerie de l'artérite de Takayasu.

Takayasu's arteritis is the most frequent inflammatory arteritis in young patients. It is characterized by the presence of giant cells and typically involves specific vascular sites: aorta and its main branches and pulmonary arteries. Inflammatory arterial involvements leads to stenosis, aneurysm, occlusion and arterial wall thickening. Diagnosis relies mainly on imaging, namely Doppler US, CT, and MRI. The imaging features of this disease are reviewed based on a retrospective review of 36 patients imaged over a 13 year period.

Particularites du cancer du sein dans le centre tunisien

Il s'agit d'une etude retrospective a propos 1135 cas de cancer du sein colliges dans le centre tunisien sur une periode de 12 ans (janvier 1990 a decembre 2001). L'age moyen des patientes etait de 49;6 ans. La taille tumorale clinique moyenne etait de 49;9 mm; 43des tumeurs etaient classees T2; 50des patientes avaient une adenopathie axillaire homolaterale et 17presentaient une metastase d'emblee. Le taux de survie a 5 ans etait de 66et la survie moyenne de 43;7 mois. Les facteurs pronostiques significatifs etaient : le delai de consultation; la taille tumorale; l'atteinte ganglionnaire; les metastases; le stade T4d; le type histologique de la tumeur primitive; le grade SBR; les embolies vasculaires et lymphatiques; la rupture capsulaire et le traitement conservateur

[XbaI polymorphism of apolipoprotein B gene in a Tunisian population: alleles frequencies and relationship with plasma lipid parameters]. / Polymorphisme XbaI du gène de l'apolipoprotéine B dans une population tunisienne: fréquences alléliques et relation avec les paramètres lipidiques plasmatiques.

Apolipoprotein B (Apo B) is a component of chylomicrons, low-density lipoproteins (LDL), very low density lipoproteins (VLDL), and intermediate-density lipoproteins (IDL) and is the ligand for the LDL receptor. Thereby, Apo B plays a central role in lipoprotein metabolism and in maintaining the normal homeostasis of serum cholesterol levels. Several Apo B restriction fragment length polymorphisms (XbaI, EcoRI, MspI) have been reported to be associated with variation in lipid levels, obesity and/or coronary artery disease. To date, no data are available on relationship between XbaI Apo B polymorphism and lipid levels in Tunisian population. Here, we report frequencies of the XbaI polymorphism of the Apo B gene and we assess the effect of this polymorphism on lipid and lipoprotein concentrations in Tunisian population. Blood samples from 296 Tunisian individuals (112 women and 184 men, aged 51.4+/-9.6 years), were analysed for total cholesterol, triglycerides, HDL-cholesterol and apolipoproteins A1 and B. In parallel, genotyping by means of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) was performed. The XbaI polymorphism was associated with differences in plasma cholesterol (p=0.04), triglyceride (p=0.02) and apolipoprotein A1 (p=0.004), individuals with the genotype X1X1 have the lowest mean levels and those with the genotype X2X2 have the highest, with the individuals heterozygous for the polymorphism having intermediate levels. According to sex, the XbaI polymorphism effect was only observed for triglyceride in men. Thus, the results demonstrate an influence of XbaI polymorphism of Apo B gene on serum total-cholesterol, triglycerides and apolipoprotein A1 concentrations among Tunisian population.

Apolipoprotein B signal peptide polymorphism: distribution and influence on lipid parameters in Tunisian population.

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.

[Homocysteinemia and coronary artery disease: a case-control study in a Tunisian population]. / Homocystéinémie et maladie coronaire: etude cas-témoins dans une population tunisienne.

We have determined the prevalence of hyperhomocysteinemia and tested its relationship with coronary heart disease in Tunisian patients. The study included 70 angiogrphically proven coronary patients and 140 age- and sex-matched healthy subjects. Plasma homocysteine folate and vitamin B12 were analyzed by immunoenzymatic methods. Hyperhomocysteinemia was considered for plasma homocysteine concentration >17 micromol/L. Mean plasma homocysteine concentration and hyperhomocysteinemia prevalence were significantly (p<0.001) higher in patients (16.3 +/- 7.9 micromol/L and 29%) than controls (12.6 +/- 4.0 micromol/L and 10%). The association between hyperhomocysteinemia and coronary heart disease persisted after adjusting on main cardiovascular risk factors (multi adjusted odds ratio, 2.99; 95% CI, 1.18-7.59; p=0.02). No association was observed between hyperhomocysteinemia and coronary disease severity and extent. This study showed an independent association between hyperhomocysteinemia and coronary heart disease, suggesting a role of hyperhomocysteinemia in atherothrombogenesis. However, causal relationship is not yet established. Until results of homocysteine-lowering therapy trials become available, hyperhomocysteinemia should be researched and treated in coronary heart disease patients.

Apolipoprotein E polymorphism in the Tunisian population: frequency and effect on lipid parameters.

OBJECTIVES: We determined the frequencies of apolipoprotein E (apo E) gene alleles and examined the association between apo E polymorphism and lipid parameters in a sample of the Tunisian population. DESIGN AND METHODS: Apo E polymorphism was investigated using PCR, and plasma lipid parameters were measured in 122 men and 111 women aged 35 to 87 years. RESULTS: The allele frequencies were epsilon2: 7.3%, epsilon3: 84.6%, and epsilon4: 8.1%. Apo E polymorphism was associated with significant differences (P<0.001) in total cholesterol, apo B and LDL cholesterol in both men and women. epsilon2 carriers had the lowest mean total cholesterol, apo B and LDL-C concentrations, and subjects with the epsilon4 allele had the highest levels. Triglycerides levels increased with the epsilon4 allele, but this did not reach statistical significance. These results remained unchanged after adjustment for age, body mass index, sex, hypertension, diabetes and smoking. However, in obese subjects (BMI>30 kg/m2), TG concentrations were significantly lower in individuals homozygous for the epsilon3 allele compared to those with the alleles epsilon2 or epsilon4. CONCLUSION: In this sample of the Tunisian population, the distribution of apo E gene alleles is similar to that observed in Southern European populations with low prevalence of the epsilon4 allele. Variations in the apo E gene play a role in determining plasma lipid levels. These data also suggest that effects of apo E alleles on lipids levels are partly dependent on environmental variables such as BMI. These findings highlight the importance of the gene/environment interaction on the deleterious effect of obesity on cardiovascular risk factors.

[Vitamin E: structure, metabolism, and functions]. / La vitamine E: structure, métabolisme et fonctions.

Vitamin E is a generic term denoting eight different isomers among which alpha-tocopherol is the most important and most active. Vitamin E metabolism is closely linked to lipids during intestinal absorption, plasma secretion and transport, and tissue uptake. It is a key compound involved in many physiological processes, such as neurological and immune functions. The most common role of vitamin E is its antioxidant effect, protecting molecules and tissues against the deleterious effect of free radicals. Vitamin E also contributes to the stabilization of biological membranes. In addition, it intervenes in the regulation of several enzymes and probably has impact on gene expression. Advancing knowledge about vitamin E has been achieved with high performance liquid chromatography, making assay accessible to many laboratories, and the use of deuterated derivatives to better apprehend its metabolism. Certain issues remain unresolved concerning the molecular basis of vitamin E's mechanism of action and the exact nature of metabolic dysfunction leading to the clinical manifestations of severe vitamin E deficiency.

[Vitamin E deficiency. Etiopathogenesis, clinical, histopathologic, and electrical features, and main etiologies]. / Le déficit en vitamine E. Etiopathogénie, aspects cliniques, histopathologiques et électriques et principales étiologies.

Vitamin E deficiency is frequently observed in human pathology. In most cases, deficiency is moderate and asymptomatic. Severe deficiency is rare and presents as a progressive neurological syndrome including cerebellar ataxia and posterior cord injury. Neuropathological and electrophysiological features confirm spinocerebellar degeneration. The pathophysiology of vitamin E deficiency nervous dysfunction is still unknown. Oxidative alterations due to the lack of the main lipid-soluble antioxidant could be involved. A few causes of vitamin E deficiency are recognized (malnutrition, impaired lipid absorption, specific anomaly of hepatic or intestinal secretion of vitamin E, excessive endogenous consumption), but diseases associated with vitamin E deficiency are numerous and divers. Symptomatic severe deficiency is constantly observed in ataxia with vitamin E deficiency and abetalipoproteinemia. Intestinal, hepatobiliary, and pancreatic diseases are often associated with more or less marked deficiency. Other pathological circumstances such as malnutrition, alcoholism, hemolytic anemia, renal failure and hemodialysis could be associated with moderated and asymptomatic vitamin E deficiency. Oral or regular administration of high-dose vitamin E is required for patients with symptomatic severe deficiency. An adapted supplementation is recommended for patients with a marginal vitamin E status.

[Vitamin E deficiency: risk factor in human disease?]. / Carence en vitamine E: facteur de risque en pathologie humaine?

Oxidative stress is suspected to intervene in certain chronic diseases. Much research has been devoted to the relationship between vitamin E, a major lipid-soluble antioxidant, and certain widespread diseases. Experimental and epidemiological proof supports a protective effect of vitamin E in a number of pathological processes such as coronary heart disease, cancer, cataract, diabetes mellitus, and Alzheimer disease. Randomized clinical trials have not confirmed a beneficial effect of vitamin E supplementation on the progression of these diseases. Certain methodological biases could however have affected these studies, explaining conflicting results. These biases include inaccuracy of vitamin E intake estimates and changes in eating habits during the course of the survey. An insufficient supplementation period using an insufficient dose and inclusion of aged and high-risk patients are the main limitations of the reported clinical trials. Large scale randomized clinical trials including healthy and low-risk subjects, along with prolonged administration of high-dose natural vitamin E, associated with synergetic compounds, and testing on morphological or biological features, will allow a better understanding of the relationship between vitamin E and chronic diseases.

Vitamin E and coronary heart disease in Tunisians.

BACKGROUND: Vitamin E (VE) is thought to be effective in preventing atherosclerosis. However, to date no consistent relationship has been identified between VE and coronary heart disease (CHD). This study was designed to assess the degree of association between VE and CHD in a sample of the Tunisian population. METHODS: Sixty-two angiographically confirmed coronary atherosclerotic patients and 65 age- and sex-matched controls were included. VE was measured in plasma and in the LDL fraction by HPLC. Cholesterol, triglycerides, and phospholipids were measured by enzymatic methods. RESULTS: A trend toward a meaningful decrease of plasma VE was observed in affected patients compared with controls (P: = 0.06). VE concentrations standardized for cholesterol and lipid concentrations were significantly lower (P: <0.02) in coronary patients than in controls (4.35 +/- 1.03 vs 4.82 +/- 1.23 mmol/mol for cholesterol-adjusted VE and 2.35 +/- 0.56 vs 2.66 +/- 0.65 mmol/mol for lipid-adjusted VE, respectively). In the LDL fraction, only cholesterol-standardized VE was significantly lower in cases than controls (3.84 +/- 1.13 vs 4.41 +/- 1.16 mmol/mol). This association between VE and CHD remained unchanged independent of age, sex, smoking habit, hypertension, and diabetes. In CHD patients, lower lipid-adjusted VE was associated with enhanced LDL susceptibility to oxidation but without alteration of the serum fatty acid profile. CONCLUSIONS: These results support the hypothesis that VE plays a role in preventing atherosclerosis.

[Determinant factors in the choice of site of delivery and the role of peripheral maternity units in a semi-urban environment in Tunisia]. / Facteurs déterminants du choix du lieu d'accouchement et place des maternités périphériques. En milieu semi-urbain tunisien.

The authors analyse, in the context of a developing country, a number of factors which can determine the choice of site of delivery in a population with access to several possibilities. The role of peripheral (or local) maternity units is considered in particular, in view of the utilisation problems which they raise. This leads to the conclusion of a degree of irrationality in the choice of health care services and the characteristics of women interacting with those of professionals when explaining the choice of site of delivery. Better management of available services is desirable in order to render peripheral maternity units more useful, and improve the medical performance at the time of delivery. Sensitization of the public and above all of health professionals nevertheless remains essential.