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New generation maraging steel developed by the aeronautical industry meet the highest mechanical standards thanks to the controlled growth of M2C carbides and B2-NiAl precipitates during aging treatment at around 500 °C. However, the literature has reported a low resistance of precipitation-hardened steel to hydrogen embrittlement that is associated with aging treatment and trapping at precipitates or reverted austenite. Thus, in relation to the complex microstructure of X23NiCoCr 13-6-3 maraging steel, hydrogen solubility and trapping was investigated using Thermodesorption Spectroscopy. A high apparent solubility of hydrogen was observed after aging that was attributed to reversible trapping at coherent B2-NiAl precipitates.

Hypericum genus is traditionally known for its medicinal use and its therapeutic and antioxidant effects. However, the toxic effect of this plant has not been much explored. Our study aimed at investigating the effect of Hypericum humifusum (Hh) leaf extracts on oxidative stress parameters in male rats. For it, we first focused on the phytochemical analysis of the aqueous and methanolic extracts of Hh leaves. Hence, Wistar rats were treated per gavage for 30 days and divided into Control (1 mL/rat, distilled water), A200 group (200 mg/kg body weight (bw) aqueous extract), A400 group (400 mg/kg bw aqueous extract), M10 group (10 mg/kg bw methanolic extract), M20 group (20 mg/kg bw methanolic extract). The phytochemical analysis revealed the presence of tannins, flavonoids, steroids, carbohydrates, and phenolic compounds. Biochemical and histological investigations were performed in plasma and liver tissue. Liver tissue homogenates were used for the measurement of malondialdehyde (MDA), catalase (CAT) and superoxide dismutase (SOD) levels. At the same time, alanine transaminase (ALT), aspartate transaminase (AST) and lactate dehydrogenase (LDH) were assayed in plasma samples. Histological study was also conducted in liver. We showed that Hh extracts reduced relative liver weight and increased ALT, AST, LDH activities in treated groups compared to control group. These results were associated with an increase of MDA levels and a decrease of antioxidant enzyme activities (CAT and SOD) in liver tissues of treated rats. Histology of liver demonstrated several alterations showing necrosis, altered hepatocytes and lymphocyte migration mainly in A200 group and dilated sinusoids, foamy appearance of hepatocytes and lymphocyte accumulation in the other treated groups. This original work indicated that chronic consumption of Hh leaf extracts has no antioxidant effect but instead it induces oxidative stress and enhances markers of cell damage which was confirmed by histological study of liver rats.

Despite conflicting data on doxorubicin (DOX) reproductive toxicity, its chemotherapeutic potential sustains its use to treat different types of cancer. This work was designed to study the protective effect of a newly synthesized thiocyanoacetamide (TA), in comparison with selenium (Se), against doxorubicin-induced in vitro toxicity in rat Sertoli cells (SCs). DOX was administered alone or in combination with Se or TA. The possible protective role of increased concentrations of TA (0.25, 0.5 and 1 mM) or Se (12, 25 and 50 μM) on SCs was tested against 1 μM of DOX. From this screening, only the least toxic doses of TA and Se were used for further analysis. DOX cytotoxicity, as well as its impact on SCs viability, mitochondrial membrane potential (ΔΨm), oxidative stress biomarkers, apoptosis and autophagy were assessed. Our results showed that DOX exerted its cytotoxic effect through a significant increase in cell death. DOX-mediated cell death was not related to autophagy nor to an overproduction of reactive oxygen species. It was rather due to apoptosis, as shown by the increased number of apoptotic cells and increased activity of caspase-3, or due to necrosis, as shown by the increase in lactate dehydrogenase (LDH) extracellular activity. Still, Bax and Bcl-2 protein expression levels, as well as ΔΨm were not altered by the different treatments. Some individual doses of Se or TA induced a significant toxicity in SCs, however, when combined with DOX, there was a decrease in cell death, LDH extracellular activity, number of apoptotic cells and caspase-3 activity. Overall, our results indicate that DOX-mediated apoptosis in cultured SCs can possibly be averted through its association with specific doses of Se or TA. Nevertheless, TA showed a higher efficiency than Se in reducing DOX-induced toxicity in SCs by decreasing not only apoptosis, but also necrosis and autophagy.

Selective Laser Melting (SLM) is a powder bed fusion process which allows to build-up parts by successive addition of layers using 3D-CAD models. Among the advantages, the high degree of freedom for part design and the small loss of material explain the increasing number of Ti-6Al-4V parts obtained by this process. However, right after additive manufacturing, these parts contain defects (surface roughness, porosity, residual stresses) which significantly decrease the High Cycle Fatigue (HCF) life. In order to minimize the porosity and residual stresses, post-processing treatments like Hot Isostatic Pressing (HIP) and Stress Relieving (SR) are often conducted. But the reduction of the surface roughness by machining is very costly and not always possible, especially for parts with complex geometry. The aim of this work is to evaluate the effect of the surface roughness of Ti-6Al-4V parts produced by SLM on the HCF behavior and to propose a methodology to estimate this effect. Three sets of specimens were tested in tension-compression: Hot-Rolled (reference); SLM HIP machined; SLM HIP as-built. For each condition, microstructure characterization, observation of the fracture surface of broken specimens, surface analysis and volume analysis were carried out respectively by Optical Microscope (OM), Scanning Electron Microscope (SEM), 3D optical profilometer and 3D X-ray tomograph. Results of fatigue testing show a significant decrease of the HCF life mainly due to the surface roughness. Along with experimental testing, numerical simulations using FEM were conducted using the surface scans obtained by profilometry and tomography. Based on extreme values statistics of a non-local fatigue indicator parameter (FIP), a methodology is proposed to take into account the effect of the surface roughness on the HCF life. Arts et Metiers Paristech, I2M, CNRS, Talence 33400, France Arts et Metiers Paristech, LAMPA, Angers 49035, France

The role of IGF-1 in promoting cancer has been investigated for many years. The aim of this study is to explore the relationship between rates of IGF-1 and NPC and to evaluate association of IGF-1 with clinical parameters.IGF-1 levels was measured by Elisa test among 82 NPC patients and 60 healthy controlsOur results showed, for the first time, a significant increased levels of IGF-I in NPC by in comparison with healthy controls (p0.01). According to the age, sex and tumor size of NPC patients, we demonstrated that IGF-1 concentrations are significantly higher in NPC aged over 30 years compared to patients aged less than 30 years (p0.01). The IGF-1 levels are, also, higher among women compared to men (p0.01). The concentrations of IGF-1 were positively correlated with tumor size of NPC patients (p0.01).IGF-I could be a good nasopharyngeal cancer diagnostic marker.

Natural green clay is mostly used in pharmaceutical and cosmetic products. The effect of this raw material from different outcrops around the world demonstrates its beneficial role on human health. The green clay from southern Tunisia is widely used in local traditional medicine and cosmetic preparations but its biological activity in vivo has not been studied yet. For this reason, this work was interested in deciphering the properties of the Tunisian green clay such as mineralogy composition and biological effect. In fact, the mineralogical study of this green clay shows two types of clay minerals such as illite and kaolinite with proportion of 75% and 25%, respectively. In order to study the biological effect, green clay was administered orally to rats for 1 h at 50, 75, 100 and 125 mg/kg doses. After that, ethanol 95% was given to these rats to induce a gastric ulcer. Then, several parameters (e.g. Ulcer index, protective rate, mucus production gastric and mucosa histology) were measured to evaluate the gastroprotective activity. The histology study shows normal gastric mucosa in rats pretreated at 75, 100 and 125 mg/kg doses and the decrease of Ulcer Index (%I = 97%) and lesions areas. The oral administing mixture of Tunisian green clay with ethanol in rats induces severe mucosal lesion and hemorrhagic bands. This clay colored by methylene blue shows that clay was linked to the mucus excreted by the stomach surface. The green clay didn't neutralize ethanol gastro toxicity and formed a layer on the gastric mucosa to protect it by a mechanical action. When investigated on rats at an effective dose treatment (75 mg/kg) for 30 days, the subchronic toxicity test of green clay did not reveal any signs of mortality and toxicity, and it demonstrated the normal hematological and biochemical parameters of rats. Thus, the Tunisian green clay can be considered as a safe natural product since it has a potential gastroprotective activity on ethanol induced gastric mucosal lesions in rats.

A series of phosphonoamidates and phosphonoamidines derivatives have been prepared with high yields and their conformations were determined. All compounds were characterized by IR, NMR Spectroscopy (1H, 13C, and 31P) and in some cases by elemental analysis and evolution study by 31P-NMR in an external lock with D2O. A DFT calculations studies was performed to identify the stability of all forms (Cis and Trans) (Syn and Anti) at the B3LYP/6-311G** level. The most stable geometry with an Anti-conformation. A comparison with the experimental results validates the level of theory. The biological activity of dimethyl cyclohexyl carbamoylphosphonate (MAmP) and diethyl cyclohexyl carbamoylphosphonate (EAmP) was evaluated. Only the association of ethyl group with phosphorus in amide gives antimicrobial capacity against S. aureus. The evaluation of the analgesic activity following a thermal stimulus showed that the rats treated with the MAmP do not present any sensation of pain. The MAmP molecule had a dose-dependent significant analgesic activity comparable to morphine effect. The hot plate test showed that the EAmP had a significant analgesic effect less than morphine and MAmP. The new compounds at low dose treatment cause an increase in the sensation of pain following a chemical stimulation that induces inflammation. So the EAmP and the MAmP can be morphemic molecules. The morphine mediates a proinflammatory phenotype and induces hyperalgesia. The MAmP was characterized by analgesic activity comparable to morphine and the EAmP was characterized by specific antimicrobial activity against S. aureus.

Introduction Lung fibrosis is a common side effect of the chemotherapeutic agent bleomycin and current evidence suggests that reactive oxygen species play a key role in the development of lung injury. We examined whether grape seed and skin extract (GSSE), a polyphenolic mixture exhibiting antioxidant properties, is able to protect against bleomycin-induced lung oxidative stress and injury. Methods Rats were pre-treated during three weeks either with vehicle (ethanol 10% control) or GSSE (4 g/kg), then administered with a single high dose bleomycin (15 mg/kg) at the 7th day. Results Bleomycin increased lung lipoperoxidation, carbonylation and decreased antioxidant enzyme activities as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx). Bleomycin also induced copper depletion from the lung and iron accumulation within the lung, but had no effect on either zinc nor manganese. Correlatively bleomycin decreased the copper associated enzyme tyrosinase, increased the zinc dependent lactate dehydrogenase (LDH) and did not affect the manganese dependent glutamine synthetase. GSSE efficiently counteracted almost all bleomycin-induced oxidative stress, biochemical and morphological changes of lung tissue. Conclusion Data suggest that GSSE exerts potent antioxidant properties that could find potential application in the protection against bleomycin-induced lung fibrosis.

Electronic-cigarettes (e-cigarette), the alternative to classic cigarettes are becoming extremely popular but their safety is not still established. Recent studies have showed cytotoxic effects of the electronic cigarette and its recharge e-liquid, in vitro. The present study was designed to evaluate e-cigarette liquid nephrotoxicity in rats. For this purpose, 32 rats were treated for 28 days as follows: Control group was injected intraperitoneally with NaCl 9 g/l; e-cigarette 0% treated group received an intraperitoneal injection of e-liquid without nicotine diluted in NaCl 9 g/l, e-cigarette treated group, received an intraperitoneal injection of e-liquid containing 0.5 mg of nicotine/kg of body weight/day diluted in NaCl 9 g/l and nicotine-treated group received an intraperitoneal injection of 0.5 mg of nicotine/kg of body weight/day diluted in NaCl 9 g/l. In nicotine group, creatinine level was increased, whereas urea and acid uric levels were decreased. In e-liquid-exposed groups, levels of uric acid and mainly urea were lower. Interestingly, after e-liquid exposure, oxidative stress status showed increased total protein and sulfhydril content, whereas superoxide dismutase and catalase activities were decreased. However, the levels of lipid peroxides were not increased after e-liquid exposure. Histological studies identified excess of cells with reduced and dark nuclei exclusively located in the renal collecting ducts. Thus, e-liquid seems to alter anti-oxidant defense and to promote minor changes in renal function parameters. This preliminary study raises some flags about possible nephrotoxicity of e-cigarette liquids in rats. As some features observed in rats may not be observed in human smokers, additional studies are needed to further qualify conclusions that might be applicable to actual users of e-cigarettes.

The crystal structure of dimethylphenylcarbamothioylphosphonate (MThmP) was obtained by reacting via one-pot synthesis without solvent at room temperature. The crystal structure of MThmP was determined by X-ray analysis (XRD). Two forms (a & b) were showed on the component MThmP which was crystallized in the monoclinic system with P21/c space group. In the first molecule (Form a), the Hirshfeld surface analysis indicates that the major contributions for the crystal packing are H⋯H (40.6%), H⋯O (24.6%)and C⋯H (18.4%) interactions. In the second crystal (Form b), the Hirshfeld surface analysis indicates the different percentage interactions: H⋯H (43.1%), H⋯O (23.3%) and C⋯H (17.8%) interactions. A DFT calculation study was performed to identify the stability of the two structures. A Fukui functions, electrostatic potential surfaces and LUMO-HOMO energy were computed in this work. Geometries of reactants, transition states and products were optimized at the B3LYP/6-311+G(d,p) level. The nucleophilic and electrophilic binding site regions were elucidated using the molecular electrostatic potential (MEP). The pharmacological studies showed that MThmP gives a significant analgesic effect less than morphine with aggravation of inflammatory state. In addition, MThmP had a potential antioxidant activity.

As built Ti-6Al-4V parts obtained by SLM and EBM, often stress-released and HIP-treated, show a very rough surface which affects the fatigue properties. In many cases of complex geometries, surface treatments can not be achieved so that the use of such parts for structural applications requires to understand and to quantify the effect of roughness on fatigue strength. This study presents an experimental and numerical approach to take into account the role of roughness on the high cycle fatigue strength of additively manufactured parts. The specific roughness of “as-built” surfaces was evaluated by several acquisition methods(2D and 3D profilometry, tomography) on “as-built” surfaces and different surface finish (machining and chemical polishing). Fatigue strength of SLM and EBM specimens with an “as built”, machined or chemically polished surface were evaluated under fully reverse tension ( R σ = 1) and torsion ( R τ = 1). Fractography analyses were performed in order to identify defects at the origin of fatigue crack initiation. Finally, a numerical approach based on finite element (FE) computation of real surface topologies was proposed to quantify the effect of the surface roughness on fatigue strength. The surface roughness was modelled from 2D and 3D profilometry and the FE computations were conducted in elasticity and elastoplasticity. The proposed numerical approach combines a non local fatigue indicator parameter (FIP) integrating the high stress gradients at notch root and a statistical description of potential initiation sites by extreme value statistics.

Tunis City is always in perpetual extension. The urban extension takes place in areas covered by quaternary alluvium. To evaluate the spatial variability of geotechnical parameters, 190 boreholes and in situ tests, across the quaternary deposits, were selected with a series of physical properties and mechanical parameters. To accomplish this research, the adopted approach was divided into four steps: (1) data collection; (2) geotechnical data georeferencing; (3) interpolation methods and (4) establishment of maps showing the spatial variability of the geotechnical parameters. Results of this study show that the quaternary deposits provide high water infiltration capacity and form the main aquifer of the study area. The low topography in Tunis City emphasizes the problem of flooding. The presence of sensitive clay causes a swelling–shrinkage behavior of the soil if the clay is dry. The disorders and damages caused by the swelling clay are especially located in the Ksar-Said Bardo–Mannouba, in Bab Saadoun, in the eastern part of Sebket Essijoumi and in the southwestern side of Tunis lagoon. On the other hand, in situ tests show that quaternary deposits contain strong shallow foundation level and vary from 0 to 5 m of thickness. These levels are made up by sand, tuff and hard clay. Muddy soils, in the Tunis City and its surrounding area, have a poor geotechnical characteristics and cause differential and absolute risk of settlement. The good bedrock in these locations is defined by muddy and sand levels and it exceed 60 m of depth. The existence of a higher concentration of gypsum causes local disorders such as the Henchir El Yahoudia site.

Resume L’HTA dans la hyalinose segmentaire et focale(HSF) est frequente et est responsable de la progression de la maladie. Elle peut etre une circonstance de decouverte de la HSF ou une complication du syndrome nephrotique. Objectifs Determiner la prevalence de l’HTA chez les patients ayant une HSF diagnostiquee en Tunisie et de decrire le profil des patients ayant une HSF hypertendus par rapport aux non-hypertendus. Patients et methodes Nous avons realise une etude multicentrique et retrospective portant sur 116 cas de HSF confirmes par l’examen histologique, recueillies par les 5 centres de nephrologie en Tunisie. Resultats La prevalence de l’HTA chez nos patients etait de 41 % avec une predominance feminine et un âge moyen des patients de 36,34 ans ± 15,71. La tension arterielle systolique moyenne chez les hypertendus etait de 153,18 mmHg. Le syndrome nephrotique etait impur par l’HTA dans 14,50 %. Les patients hypertendus etaient plus obeses. La proteinurie etait plus intense chez les patients normotendus par rapport aux hypertendus avec une proteinurie moyenne de 5,67 ± 4,51 g/24 h avec une difference non significative. L’insuffisance renale etait significativement plus presente chez les patients hypertendus. Les lesions vasculaires etaient presentes a la biopsie renale dans 39,45 % chez les sujets hypertendus associees a une insuffisance renale dans 58,50 %. Le traitement etiopathogenique de la HSF reposait essentiellement sur la corticotherapie a pleine dose. Conclusion L’HTA est souvent presente dans la HSF et sa prise en charge doit etre precoce afin de ralentir la progression de la maladie renale chronique.

The practical importance of fatigue failure in steam turbine materials has directed many experimental research towards assessing the physical reason for material sensitivity to corrosion fatigue and providing design rules for engineers. Metallic materials used in steam turbine are exposed to cyclic loading at high temperature and steam environment, during their service life. In this study, an original fatigue testing setup was developed to investigate the effect of aqueous solutions and temperature on the fatigue strength on the martensitic stainless steel X19CrMoVNbN11-1 used for rotating blades and (ii) a cast G17CrMoV5-10 steel used for casing. Fatigue tests were carried out in two environments: (i) in air at 90 °C and (ii) in distilled water at 90 °C (pH = 7.2 and 0 2 = 3 ppm) at a loading frequency of 1 Hz. Internal and surface crack initiation are observed in air at 90 °C, whereas in purified water at 90 °C, the crack initiated in the surface at corrosion defects. The decrease observed in the corrosion fatigue strength of specimens was more important at high plastic strain level of that on similar specimens tested in air. Based on fractography analysis, fatigue crack initiation mechanisms in air and in distilled water were identified. Two different scenarios for fatigue damage depending on the microstructure are proposed and will be discussed in this paper.

Thioamides (Thm) have diverse biological activities. This work presents the development and validation of simple, rapid and accurate spectrophotometric method for the analysis of Thm derivatives in pure form and in plasma. This spectrophotometric method has not been used before for determination of Thm. A review of the literature revealed that the monitoring of S− group assay is based on the reaction with DTNB according to the Ellman method to form a yellow complex which absorbs at 412 nm. To assay the thioamides according to this method it is necessary to make the basic medium have S− to react with the DTNB. Experimental conditions affecting the color development were studied and optimized. The proposed spectrophotometric procedures were effectively validated with respect to linearity, ranges, precision, accuracy, specificity, robustness, detection and quantification limits. Calibration curves of the formed colored product with DTNB showed good linear relationships over the concentration ranges (0, 50, 100, 500, 1000, 1500 mg/L). The proposed method was successfully applied to the assay of Thm monitoring with good accuracy. The principal advantages of the proposed method were rapidity and suitability for the routine quality control assay of the drug alone and in monitoring form without interference.

Emissions characteristics from the combustion of five date palm residues, DPR, (Date Palm Leaflets, Date Palm Rachis, Date Palm Trunk, Date Stones and fruitstalk prunings) in a laboratory scale furnace were investigated. Release of gaseous products such as CO 2 , CO, VOC, NO x and SO 2 were measured at 600–800 °C. The main goal was to analyze thermal behaviors and gaseous emissions in order to select the most convenient biofuel for an application in domestic boiler installations. Regards to biofuel characteristics, date stone have the highest energy density (11.4 GJ/m 3 ) and the lowest ash content (close to 1.2%). Combustion tests show that among the tested date palm residues, date stone may be the promising biofuel for the design of combustion processing system. However, a special attention to the design of the secondary air supply should be given to prevent high emissions of CO and volatile matters.

International audience; Date palm residues are an attractive source of biomass energy since they are renewable, abundantly available and do not compete with food crops. Pyrolysis and combustion may be efficient methods of exploiting energy from these biomass resources. The purpose of this research was to investigate the thermal behavior of date palm biomass in order to evaluate their usefulness for energy production. In fact, ultimate and proximate analyses as well as thermal behavior of different date palm residues (date palm leaflets (DPL), date palm rachis (DPR), date palm trunk (DPT), date stones (DS) and fruitstalk prunings (FP)) were investigated. Non-isothermal thermogravimetric analyses (TGA) were performed to assess fuel reactivities under inert and oxidative atmospheres. Thermal degradation of all samples has exhibited quite similar behavior except DS. In contrast, different properties (e.g., reactivity, HHV or activation energy) were obtained, which may be attributed to a difference between tree parts composition (branches, trunk, fruit…). Thus, DPT and FP were found to be the most reactive materials in inert conditions; while in oxidative conditions, DPR is the highest one. In addition, activation energies corresponding to devolatilization regions under inert and oxidative conditions were 49.8, 45.2, 52.7, 50.9, 89.1 kJ mol−1 and 58.9, 49.6, 67.6, 57.7, 110.7 kJ mol−1 for DPL, DPR, DPT, DS and FP respectively. The obtained data, sample properties along with thermal behavior under inert and oxidative atmospheres as well as kinetic parameters, allowed the comparison of the obtained results with other biofuels and can be useful for the design of processing system for energy productions.

Resume Introduction Les angiosarcomes du sein sont des tumeurs vasculaires rares. Elles representent 0,4 % de l’ensemble des tumeurs malignes du sein et 3 a 9 % des sarcomes mammaires. Patients et methode Il s’agit d’une etude retrospective portant sur dix cas d’angiosarcome (neuf femmes et un homme) du sein colliges au service d’immuno-histocytologie de l’hopital Salah Azaiez sur une periode de 31 ans entre 1977 et 2007. Resultat La moyenne d’âge etait de 40 ans. Le mode de decouverte a ete un nodule du sein avec un etat general conserve dans tout les cas. La taille moyenne de la tumeur etait de 5,5 cm. La mammographie a revele une masse bien limitee dans cinq cas. Une mastectomie a ete pratiquee chez huit patients associee dans quatre cas a une radiotherapie et dans un cas a une chimiotherapie. Le traitement conservateur a ete indique dans deux cas. L’examen histologique a montre un aspect typique d’angiosarcome dans huit cas. La survie sans recidive allait de quatre mois a 13 ans. Deux patientes ont ete perdues de vue apres le diagnostic d’angiosarcome. Quatre de nos patients n’ont pas developpe de recidive locale ou de metastase a distance. Deux patientes ont developpe une recidive locale ou de metastase a distance. Deux patientes ont developpe une recidive locale apres huit et 18 mois. Une patiente a developpe une metastase osseuse apres 29 mois. Conclusion Les angiosarcomes du sein sont des tumeurs rares qui posent un probleme diagnostique differentiel avec les angiomes. En consequent, une surveillance rapprochee et reguliere s’impose pour les tumeurs vasculaires.

Urban geology provides information on urban geologic environments as a scientific basis for planners and engineers for rational land use planning and urban development. Such mapping can be classified in terms of purpose, content and scale. In this study, procedure for preparation of engineering geological mapping in Tunis City (Tunisia) is given, as a case study. The main restricting factors for urban development: such as lithology; topography; slope; seismotectonic; water table depth; flooding susceptibility and seismic-induced effects were considered in the preparation of maps. All these information layers were manipulated using the Geographic Information System (GIS), and they were then combined to produce uniform engineering geological maps. Results are illustrated as a suitability map for construction in the study area. Consequently, the study area was categorized into four different zones as: (1) a high region with potential risk of superficial perturbation; (2) a low and flat zone with flooding risk; (3) a low zone with flooding and probability of sliding risk; (4) a region with mud levels and settlement risk.

Objective The aim of this review is to study natural history, presentation, treatment and prognosis of head and neck liposarcomas. Methods We carry a retrospective study about 15 patients diagnosed and treated in our department between 1969 and 2001. Therapeutic modalities included surgery, radiotherapy and chemotherapy. Results Tumors were mostly localized at the neck (4 cases) and the scalp (3 cases). Cervical lymphadenopathy was found in 1 case. Chest X-ray found showed metastases in 2 cases. Histological types of liposarcomas were the following: myxoid (5 cases), well differentiated (4 cases), pleomorphic (4 cases), round cell (1 case) and dedifferentiated (1 case). Twelve patients underwent surgery. Complete excision was performed in 7 cases. In the other 5 cases, exeresis was incomplete and 4 of them received postoperative radiotherapy. Three patients were not operated because of vascular involvement (1 case) or metastasis (2 cases), and they all received radiotherapy alone. After initial treatment, complete remission was achieved in 7 cases (46.7%). A recurrence occurred in 8 cases (53.3%). Two of these patients were reoperated and another one received chemotherapy. In the other 5 cases, the tumor was uncontrollable and no additional treatment has been proposed. Five-year survival rate was 87% for patients who underwent surgery alone, 75% for those who underwent surgery and postoperative radiotherapy, and 0% for those treated by radiotherapy alone. Conclusion The mainstay of treatment of head and neck liposarcomas is surgical excision and the prognosis is largely determined by the histological grade and the clinical stage.

Garlic is regularly consumed and is known to have diverse biologic activities, particularly due to its antioxidant properties. In this study, we hypothesized that crude garlic can prevent iron-mediated oxidative stress in a rat model of nutritional iron overload, and we used an in vitro model to confirm the results. For the in vivo studies, rats received a basal diet supplemented with or without carbonyl iron (3%) and were fed distilled water or garlic solution (1g/kg body weight) by gavage for 3 weeks. The presence of both garlic and iron led to a 2-fold increase in plasma iron and a 50% increase in liver iron as compared with iron alone. However, garlic did not offer any protection against iron-induced oxidative stress. Duodenal divalent metal transporter-1 mRNA expression was fully repressed by iron and by the combined treatments but was also reduced by garlic alone. To confirm these data, we tested the effect of diallyl disulfide, one of the active components in garlic, in vitro on polarized Caco-2 cells. A 24-hour treatment decreased iron uptake at the apical side of Caco-2 cells but increased the percentage of iron transfer at the basolateral side. This probably resulted from a modest induction of ferroportin mRNA and protein expression. These results suggest that garlic, when given in the presence of iron, enhances iron absorption by increasing ferroportin expression. The presence of garlic in the diet at the dose studied does not seem to protect against iron-mediated oxidative stress.

The DNA adenine methylase of Salmonella typhimurium methylates adenine at GATC sequences. Strains deficient in this methylase are not well transformed by methylated plasmids, but unmethylated plasmids transform them at high frequencies. Hemimethylated daughter molecules accumulate after the transformation of dam(-) strains with fully methylated plasmids, suggesting that hemimethylation prevents DNA replication. It will also be shown that plasmids isolated from dam(-) bacteria are hemimethylated by restriction enzyme digestion. These results may explain why newly formed daughter molecules are not substrates for immediate reinitiation of DNA replication in dam(-) bacteria.

Objectifs Etude de l’association entre carcinome de la thyroide et thyroidite de Hashimoto(TH). Materiel et methodes Il s’agit d’une etude retrospective entre 2001 et 2002 portantsur une serie de 78 patients operes avec a l’histologie un diagnostic d’une thyroidite de Hashimoto. Les caracteristiques cliniques et les examens complementaires realises avant lachirurgie ont ete notes. Resultats L’âge moyen etait de 44,6 ans avec 77 femmes et un seul homme. 12 patientsayant une TH, sous forme nodulaire, presentaient un cancer de la thyroide, dont onze casde carcinomes papillaires (14,1 %) et un cas de lymphome B non-Hogkinien la thyroi de.La taille tumorale est en moyenne de 26 mm allant de 4 a 60 mm. Il y avait un microcancer(taille Conclusion On ne retrouve pas une incidence anormalement elevee de carcinome de lathyroide sur cette population hautement selectionnee de TH.

Resume Objectifs. – Le carcinome epidermoide hypopharynge est associe a l’un des pronostics les plus defavorables des cancers de la sphere ORL. L’objectif de ce travail etait d’analyser ses modalites therapeutiques a l’institut Salah-Azaiz (Tunis) et de comparer leurs resultats. Patients et methodes. – Cette etude retrospective porte sur 271 carcinomes epidermoides de l’hypopharynx, colliges au service de chirurgie carcinologique cervicofaciale et ORL de l’institut Salah-Azaiz sur une periode de 25 ans (1977 a 2002). L’âge moyen des patients etait de 56 ans ; le sex-ratio etait en moyenne de 1,2 (homme/femme). L’indication d’un traitement a visee curative a ete initialement retenue pour 149 (55 %) patients, qui ont ete les seuls retenus pour l’analyse des resultats. Resultats. – Nous avons retenu l’indication d’un protocole incluant chirurgie et radiotherapie postoperatoire pour 26,2 % des patients. Le taux de mortalite postoperatoire etait de 5,1 % ; le taux de morbidite operatoire etait de 46,2 %. Pour 13,5 % des patients, la radiotherapie postoperatoire a ete definitivement interrompue en raison d’une alteration progressive de l’etat general en cours de traitement. Nous avons pose l’indication d’une radiotherapie exclusive pour 59,7 % des patients. L’âge moyen etait de 56 ans et le sex-ratio de 1,2. La telecobaltotherapie externe etait delivree en fractionnement et etalement classiques. La radiotherapie a du etre definitivement interrompue en cours de realisation dans 32,6 % des cas devant une aggravation de l’etat general ; le taux de morbidite liee a la radiotherapie etait de 33,3 %. Un protocole de conservation d’organe avec chimiotherapie neoadjuvante a ete propose a 21 patients (14,1 %). L’âge moyen etait de 53 ans (28 a 65 ans) et le sex-ratio (homme/femme) de 0,5. Le taux de survie globale etait de 25,5 % a un an, 18,1 % a deux ans, 11,4 % a trois ans et 7,4 % a cinq ans. Tous les patients a qui a ete proposee une chimiotherapie sont decedes en cours de traitement. Les taux de survie a deux et a cinq ans des patients traites par chirurgie et irradiation et par irradiation exclusive etaient respectivement de 21,5 et 12 %, et 18,3 et 10 %. La difference de survie entre ces deux populations therapeutiques n’etait pas significative (p = 0,08). Conclusion. – Tandis que la chimiotherapie neoadjuvante apparait dans notre serie comme grevee d’une lourde mortalite, l’association chirurgie–radiotherapie et la radiotherapie exclusive semblent d’une efficacite similaire dans le traitement du carcinome hypopharynge.

Resume Objectifs. – Le carcinome epidermoide hypopharynge est associe a un pronostic defavorable, auquel l’envahissement ganglionnaire cervical et les metastases a distance contribuent. L’objectif de cette etude etait d’evaluer la frequence, le mode et la signification pronostique de ses metastases regionales et a distance. Patients et methodes. – Les auteurs rapportent une etude retrospective portant sur 271 carcinomes epidermoides de l’hypopharynx, colliges au service de chirurgie carcinologique cervicofaciale et ORL de l’institut Salah-Azaiz de 1977 a 2002. La frequence et les caracteres histocliniques des metastases regionales et a distance ont ete evalues, ainsi que leur signification pronostique chez les 155 patients traites dans un but curatif. Resultats. – 39,1 % des cancers etaient classes N0, 24,4 % N1, 10,7 % N2 et 25,8 % N3 (UICC 2002). Les adenopathies cervicales etaient significativement plus frequentes pour les tumeurs classees T3T4 que pour les T1T2 (soit, pour les tumeurs des sinus piriformes, celles de la region retrocricoarytenoidienne, celles de la paroi posterieure et celles etendues de l’hypopharynx, respectivement : p = 0,001, p = 0,007, p = 0,047, et p = 0,0005). Trente-deux patients ont beneficie d’un evidement ganglionnaire cervical. Parmi ceux dont le cancer a ete classe N0, il a ete trouve 46,9 % d’atteintes ganglionnaire (N+) ; les frequences de la rupture capsulaire n’etaient pas significativement differentes pour les cancers classes N0N1 et pour ceux qui etaient N2N3 ( p = 0,11). Les taux de survie globale a deux et a cinq ans etaient respectivement de 32,5 et 20,5 % pour les patients dont la tumeur etait classee N0, 10,9 et 0 % si elle etait N3. Les differences de taux de survie a deux et a cinq ans entre les patients dont la tumeur etait N0N1 et ceux dont elle etait N2N3 etaient significatives ( p = 0,04). Un echec ganglionnaire cervical a ete constate chez 18,5 % des patients. Le site tumoral n’influencait pas significativement le taux d’echec ganglionnaire ( p = 0,98), non plus que le statut clinique N ( p = 0,34). La rupture capsulaire etait un facteur significatif de prediction d’un echec ganglionnaire ( p = 0,007). Le taux de dissemination metastatique a distance etait de 2,6 % au premier examen, et secondairement de 12,3 %. Les metastases a distance etaient significativement plus frequentes chez les patients dont le cancer etait initialement classe N2N3 que chez ceux dont il etait N0N1 ( p = 0,03), ainsi qu’en cas de rupture capsulaire ( p = 0,0009). Conclusion. – Le carcinome epidermoide de l’hypopharynx est caracterise par une grande lymphophilie, qui est liee a l’extension locale, et par la grande frequence des metastases ganglionnaires occultes. Le statut clinique ganglionnaire ne semble pas influencer la probabilite de survie ; cependant, la rupture capsulaire constitue un facteur de prediction d’un echec ganglionnaire cervical et de metastases a distance. Les metastases a distance sont frequentes, particulierement en cas de tumeur etendue aux plans local ou regional, et la probabilite de survie est dans ce cas nulle a un an.