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We realize simplified-tomography experiments on irregular rough particles using interferometric out-of-focus imaging. Using two angles of view, we determine the global 3D-shape, the dimensions, and the 3D-orientation of irregular rough particles whose morphologies belong to families such as sticks, plates, and crosses.

Bien que la dissémination métastique soit la cause la plus fréquente de décès des patients cancéreux, le nombre de médicaments ciblant spécifiquement ce phénomène est actuellement très réduit. Les bases d'une stratégie de découverte de futurs médicaments antimétastatiques sont fragiles en raison du grand nombre d'inconnues caractérisant la connaissance globale des mécanismes de la cascade métastique. Par ailleurs, les modèles expérimentaux actuels sont trop réducteurs. Un certain nombre de cibles ont été identifiées mais trop peu sont validées. Parmi ces cibles, les gènes suppresseurs de tumeurs sont les plus prometteuses. Malgré tout, une dizaine de molécules ne ciblant que les métastases sans altérer la croissance de la tumeur primaire (éradicable par la chirurgie) ont été identifiées et évaluées expérimentalement au cours des quinze dernières années, apportant la preuve du concept. La poursuite de cet effort gagnerait en efficacité si les objectifs étaient plus précisément définis. En particulier, il est important de distinguer les molécules destinées à prévenir l'essaimage des métastases à partir de tumeurs primaires en début de progression (action préventive) de celles qui devront faire régresser des métastases établies ou inhiber la transformation de métastases occultes en macrométastases (action curative). Le deuxième objectif est a prioriplus pertinent dans les conditions actuelles de détection des tumeurs et devrait faire l'objet d'un plus grand effort de la communauté scientifique.

L’endométriose est une pathologie fréquente chez la femme, ayant comme principale répercussion une symptomatologie douloureuse. De plus, il a été mis en évidence que l’endométriose était une cause importante d’infertilité et que différentes complications obstétricales pouvaient être liées à cette pathologie. La rupture utérine est une complication rare mais grave, dont l’incidence tend à diminuer avec le dépistage des femmes à risque, néanmoins la morbi-mortalité maternelle et fœtale qu’elle entraîne reste importante. Nous avons été confrontés à un cas de rupture utérine postérieure chez une patiente de 36ans, primipare à terme dépassé en postpartum immédiat. La patiente a comme antécédent principal une chirurgie du torus utérin pour endométriose responsable d’infertilité. L’issue a été favorable pour la mère, après une prise en charge chirurgicale par laparotomie, et pour l’enfant. Dans la littérature, deux cas ont été rapportés de rupture utérine après la chirurgie de l’endométriose, c’est pourquoi nous avons trouvé intéressant de rapporter ce cas rare. Au vu de l’augmentation de la prise en charge chirurgicale de cette maladie, il semble pertinent de se demander si, à l’avenir, nous devrions rester plus vigilants lors du suivi de la grossesse de ces femmes.

A multi-exposure digital in-line hologram of a particle field is recorded by two successive pulses of different wavelengths. During the reconstruction step, each recording can be independently analyzed by selecting a given wavelength. This procedure enables avoiding the superimposition of particle images that may be close to each other.

Identifier les éléments permettant de prédire le risque réel de prématurité en situation de menace d’accouchement prématuré.

AbstractRadial distributions of the total fission rate and the 238U-capture-to-total-fission (C8/Ftot) ratio were measured in SVEA-96+ and SVEA-96 Optima2 assemblies during the LWR-PROTEUS program. Fission rates predicted using MCNPX with JEFF-3.1 cross sections underestimated the measured values in the gadolinium-poisoned pins of the SVEA-96 Optima2 assembly; similarly, C8/Ftotratios were overestimated in some gadolinium-poisoned pins of the SVEA-96+ assembly. A considerable effort was invested at the Paul Scherrer Institut to explain the discrepancies in gadolinium pins, without success. Recently, gadolinium cross sections were measured at the Rensselaer Polytechnic Institute by Leinweber et al. and differed significantly from current library values. ENDF/B-VII.0 gadolinium cross sections have currently been modified to include the new measurements, and these data have been processed with NJOY to yield files usable by MCNPX. Fission rates in the gadolinium-poisoned fuel pins of the SVEA-96 Optima2 pins were increased by 1.4 to 2.0% using the newly produced cross sections, yielding to a better agreement with the experimental values. Predicted C8/Ftotratios were decreased on average by 1.7% in both clustered and unclustered groups of gadolinium-poisoned fuel pins of the SVEA-96+ assembly correcting the overpredictions previously reported in the clustered gadolinium pins. Earlier reported discrepancies observed in PROTEUS integral experiments, between measured and calculated reaction rates in the gadolinium-poisoned pins, might thus be due to inaccurate gadolinium cross sections. The PROTEUS results support the new thermal and epithermal gadolinium data measured by Leinweber et al.

To explore the mechanisms whereby estrogen and antiestrogen (tamoxifen (TAM)) can regulate breast cancer cell growth, we investigated gene expression changes in MCF7 cells treated with 17β-estradiol (E2) and/or with 4-OH-TAM. The patterns of differential expression were determined by the ValiGen Gene IDentification (VGID) process, a subtractive hybridization approach combined with microarray validation screening. Their possible biologic consequences were evaluated by integrative data analysis. Over 1000 cDNA inserts were isolated and subsequently cloned, sequenced and analyzed against nucleotide and protein databases (NT/NR/EST) with BLAST software. We revealed that E2induced differential expression of 279 known and 28 unknown sequences, whereas TAM affected the expression of 286 known and 14 unknown sequences. Integrative data analysis singled out a set of 32 differentially expressed genes apparently involved in broad cellular mechanisms. The presence of E2modulated the expression patterns of 23 genes involved in anchors and junction remodeling; extracellular matrix (ECM) degradation; cell cycle progression, including G1/S check point and S-phase regulation; and synthesis of genotoxic metabolites. In tumor cells, these four mechanisms are associated with the acquisition of a motile and invasive phenotype. TAM partly reversed the E2-induced differential expression patterns and consequently restored most of the biologic functions deregulated by E2, except the mechanisms associated with cell cycle progression. Furthermore, we found that TAM affects the expression of nine additional genes associated with cytoskeletal remodeling, DNA repair, active estrogen receptor formation and growth factor synthesis, and mitogenic pathways. These modulatory effects of E2and TAM upon the gene expression patterns identified here could explain some of the mechanisms associated with the acquisition of a more aggressive phenotype by breast cancer cells, such as E2-independent growth and TAM resistance.

AbstractThe MUSE program (multiplication with an external source) is in progress at the MASURCA critical facility at the Cadarache Research Center of the Commissariat à l’Energie Atomique in France. The program is dedicated to the physics studies of accelerator-driven systems in support of transmutation studies of minor actinides and long-lived fission products. It began in 1995 with the coupling of a Cf source in MASURCA and was followed by a commercial (d,T) source. In 2001, a specially constructed (d,D)/(d,T) neutron generator (GENEPI) was placed in MASURCA and the MUSE-4 program commenced.We describe the first phases of the MUSE-4 program, with data presented that were obtained up to about the summer of 2002. We present some results from the “reference” configuration, which can operate at critical. We present traverses of measured fission reaction rates, with comparison to calculations. Also in the reference configuration, we performed activation foil measurements and present these results compared to calculations.Because a major objective of the MUSE program is to test and qualify methods of subcritical reactivity measurement, we have devoted a major portion of our studies to this area. We have used classical methods (rod drop, source multiplication) to attempt to measure the subcritical level. In these early phases we studied core configurations of around keff= 0.995. Deeper subcriticality (keff= 0.96) was achieved by inserting a safety rod.In addition to the methods mentioned above, we have devoted a lot of effort to pulse neutron source, fluctuation (Rossi-α and Feynman-α), and transfer function methods (e.g., cross-power spectral density). We present our preliminary results of all the methods, with some discussion regarding cross comparison.

The effect on model phospholipidic membranes of LEW-7/S1, a synthetic derivative of diosmin, has been investigated by Quasielastic Light Scattering (QLS) and Fourier Transform Infrared Spectroscopy (FT-IR). The results of the first technique show a modification of the phase transition and a decrease of the elastic modulus of the bilayer in the presence of the drug. The FT-IR results indicate interactions in the polar head and the aqueous interface regions.

The aim of this study was to investigate TSH and PRL response to TRH and domperidone, an antidopaminergic drug which does not cross the blood-brain barrier, in 16 patients with primary empty sella (PES) and either normal or elevated plasma PRL level and to compare it with the response observed in 8 patients with prolactinoma. In the patients with PES and hyperprolactinemia, the PRL response to TRH was significantly lower than in the controls and the patients with PES and normal PRL, which suggests there is impaired PRL synthesis and release in cases of PES with hyperpro-lactinemia. The TSH response to domperidone was significantly elevated in patients with PES and either normal or elevated PRL, as in patients with prolactinoma. The PRL response to domperidone was significantly reduced in patients with PES and hyperprolactinemia as in patients with prolactinoma. These results suggest that in PES as in prolactinoma the inhibiting dopaminergic tone is increased on the thyrotropic cells and reduced on the lactotropic cells in PES with elevated PRL and that some patients with PES might bear a microprolactinoma in the bottom of the sella which remained undetected by the CT scan.

Gastrozymin differed from secretin in several chromatographic and solubility characteristics. However, it showed a spectrum of activities which resembled those of secretin, including stimulation of pepsin, hepatic bile secretion, and pancreatic bicarbonate secretion. This study revealed differences in the quantitative ratios of these activities when induced by secretin or gastrozymin. In particular, if the ratio of the stimulation of pepsin secretion to that of pancreatic juice bicarbonate was 1:1 for secretin, it was 4:1 for gastrozymin. Further purification will show whether all these effects are induced by one molecule or by several peptides. It will also determine whether there is a structural relationship between gastrozymin and secretin or its precursor(s).

Isolated and washed human erythrocytes were incubated with various concentrations of nitrate, nitrite or trinitrine. Erythrocyte deformability based on filtration index, membrane chemical composition evaluated with free cholesterol (FC), phospholipids (PL) and proteins, and erythrocyte changes in methemoglobin, malondialdehyde, cAMP and cGMP productions were the parameters investigated thereafter. Nitrate and trinitrine have improved erythrocyte deformability, effect related to modified (FC+PL)/proteins ratios and likely enhanced protein binding to membrane while nitrite has induced a hig methemoglobinemia that may have blotted out this positive effect.

A 66-year-old woman who had used hair lacquer several times a day for many years presented with a clinical picture of diffuse interstitial pulmonary disease. A systemic and lung immune reaction was indicated by a high proportion of lymphocytes and elevated IgG and IgA in the broncho-alveolar lavage fluid, numerous plasmocytes in the lung biopsy and LE cells and antinuclear antibodies (1/1000) in the peripheral blood. A lacquering agent (copolymer maleic anhydride-butylic alcohol) was detected in the biopsy by nuclear magnetic resonance. To the best of our knowledge, this is the first demonstration of such an agent in the lung of a subject with thesaurosis.

ABSTRACTOligopeptidic drugs such as β-lactams and angiotensin-converting enzyme inhibitors share the same carriers in humans and animals, which results in possible pharmacokinetic interactions. To model such interactions, the effects of quinapril on cephalexin pharmacokinetics were investigated in rats. Blood cephalexin concentrations were measured by liquid chromatography, and the data were analyzed by a noncompartmental method and by fitting a bicompartmental model by a nonlinear mixed-effect modeling approach. Five groups of eight rats were examined. In the first three groups, cephalexin elimination kinetics after intra-arterial administration alone or in combination with quinapril given by the parenteral or the oral route were studied, and the occurrence of a pharmacokinetic interaction was not revealed. The absence of an effect of quinapril on cephalexin elimination after parenteral administration might be explained either by the higher affinity of cephalexin for the renal anionic transport system than that of quinapril or by the much higher concentrations of cephalexin than those of quinapril. In the last two groups, cephalexin was administered by the oral route alone or in combination with quinapril. The mean area under the concentration-time curve (AUC) for cephalexin was increased by ca. 30% by coadministration of quinapril (40.1 versus 31.4 mg · h/liter;P= 0.04). The mean elimination clearance of cephalexin was significantly decreased by quinapril, from 0.81 to 0.64 liter/h/kg of body weight (P< 0.05), probably by competitive inhibition of cephalexin secretion at the tubular level. The mean absorption rate constant of cephalexin was significantly lowered by quinapril (from 0.249 to 0.177 h−1;P< 0.01), without modification of the extent of absorption (89%). This pharmacokinetic interaction could be explained by competitive inhibition of cephalexin active transport by quinapril at the intestinal level.

Data on the influence of calcium antagonists on glucose tolerance and insulin release in humans are conflicting. The present double-blind, double-dummy, controlled trial was designed to investigate the effect of a short-term (7 days) treatment with nitrendipine, 20 nig b.i.d.; nitrendipine, 20 nig once daily: or placebo on blood glucose and plasma insulin and C-peptide response to an intravenous glucose load in mildly or transiently hypertensive nondiabetic obese patients. No statistically significant differences were found in fasting glucose, insulin, and C-peptide, or in the glucose disappearance rate and in any of the parameters for insulin and C-peptide response after i.v. glucose, between the three groups of patients. However, a slight decrease in early insulin response to glucose was observed in the nifedipine and the nitrendipine groups. This study confirms that calcium antagonists have no clinically relevant effect on glucose homeostasis even if a slight alteration of insulin release after glucose load cannot be ruled out.