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ISBN 3-8055-3546-5

In order to define clinical patterns of light-chain amyloid (AL) polyneuropathy, we reviewed the data of 24 patients. At diagnosis, the mean duration of the symptoms was 21 months (range,...

Background Neurofibromatosis 1 (NF1) belongs to the autosomal dominant neurocutaneous disorders' group, which mainly includes NF1 and NF2, tuberous sclerosis, von Hippel-Lindau disease and Cerebral Cavernous Malformations (CCMs). NF1 has a major impact on the nervous system, eye, skin, bone or cardiovascular system. Cerebrovascular lesions have been reported in NF1 including aneurysm, pseudoaneurysm, arteriovenous malformations, vascular stenosis or occlusion and Moya moya syndrome. Objective To report a case of an NF1 patient with multiple CCMs. Observation A 47-year-old man with cafe-au-lait skin lesions, countless cutaneous neurofibromas, short stature and scoliosis was admitted for progressive spinal cord compression due to histologically proven neurofibroma. Systematic cerebral MRI screening including gradient echo sequences showed multiple asymptomatic CCMs. Screening of CCM1, CCM2 and CCM3 genes was negative while a deleterious frameshift mutation was identified in NF1 gene. Conclusion While single CCM can occur in NF1 patients following radiation exposure, they are only rarely reported in non-irradiated NF1 brain. Even if it could be a fortuitous association, plausible links and explanations exist. If cerebral MRI can be systematic in NF1 to detect asymptomatic gliomas, used protocols in neuroradiology do not usually include gradient echo sequences, the most sensitive test for CCM detection, leading possibly to failure to detect these vascular lesions. More reports having this combination and further investigations of NF1 families will certainly provide a better understanding of links between these 2 phakomatoses, as recently reported with “multiple meningiomas” phenotype associated with multiple CCMs in patients with CCM3 gene mutations or cafe-au-lait skin lesions in CCM1 mutation carriers.

Supposant connue la structure de la molecule de benzene, on a reconstitue la structure du cristal monoclinique (benzene III) par analyse des interactions moleculaires en dynamique classique a temperature ordinaire et diverses pressions, (2.5 1) dans la fonction exponentielle du potentiel de BUCKINGHAM). Ils generalisent et confirment les resultats deja obtenus sur le benzene orthorhombique (benzene I) pour diverses temperatures et pressions, et rappeles ici.

Crystal and molecular structures of hexachlorobenzene C6Cl6 were investigated by molecular-packing analysis with a computed dynamical model. This model includes thermal motions and molecular deformations. Several crystalline structures with monoclinic symmetry P21/c have been found by the calculation. Factors which influence the stability of these structures are investigated. The lowest-energy structure, labeled I, agrees with the experimental one. Calculated crystal and molecular parameters agree with data determined by x-ray diffraction at 296 K. While no temperature-induced phase transition has been found from 296 to 124 K at ambient pressure, a phase transformation has been evidenced numerically at 0.43 GPa and 296 K. The monoclinic pressure-induced phase, stable above 0.43 GPa, is labeled II.

Resume Propos Bien que la sclerose en plaques (SEP) et le syndrome primaire des antiphospholipides soient habituellement definis selon des criteres specifiques qui permettent de les distinguer, dans certains cas la transition entre les deux maladies a partir de donnees cliniques et d'imagerie cerebrale apparait difficile. Methodes Nous nous sommes donc propose d'etudier les taux d'anticorps anti-phospholipides (anticorps anticardiolipides, anti-beta2 glycoproteine 1 et antiphosphatidylethanolamine), d'anticorps antinucleaire, d'anticorps anti-ADN natif, d'anticorps anti-prothrombinase et du facteur rhumatoide chez 62 patients (sex-ratio F/M = 1,48; moyenne d'âge: 43,4 ± 23,6 ans) pour lesquels le diagnostic de SEP selon les criteres de Poser a ete etabli et 31 sujets temoins normaux (sex ratio F/M = 9,3 ; moyenne d'âge = 37 ±17 ans). Resultats La presence d'anticorps anti-phosholipides a ete trouvee a un taux significatif (IgG anticardiolipides > 20 UI, anti-beta2 glycoproteine 1 positive, anticorps antiphosphatidylethanolamine positive) chez seulement cinq patients (8%) suivis pour une SEP ; des anticorps anti-nucleaire eleves (l/320eme et l/1280emc) ont egalement ete mis en evidence chez deux autres d'entre eux. Conclusion Contrairement a certaines etudes recemment publiees, nos resultats ne retrouvent pas un lien significatif entre SEP et anticorps anti-phospholipides et vont contre les arguments d'un mecanisme etiopathogenique commun.

Coca-Erythroxylum coca Lamarck var. coca-remains one of the most common plants of the folk medicine of Bolivia used as a general stimulant. Aymara and Quechua natives prefer to chew the sweeter coca leaves from the Yungas (tropical mountain forests of the eastern slopes of the Andes) rather than those from the Chapare lowlands. The contents in cocaine and minor constituents of leaf samples cultivated in these regions does not rationalize this choice.

In order to study the influence of pancreatic enzyme secretion on the intestinal absorption of mediumchain fatty acids (MCFA), three growing pigs (mean body-weight 61 kg) with ligated and severed pancreatic ducts were fitted with a permanent fistula in the duodenum and with two catheters in the portal vein and carotid artery respectively. An electromagnetic flow probe was also set up around the portal vein. A mixture of octanoic and decanoic acids, esterified as medium-chain triacylglycerols, together with maltose dextrine and a nitrogenous fraction was continuously infused for 1 h into the duodenum. Samples of blood were withdrawn from the two vessels at regular intervals of time for 8 h and further analysed for their non-esterified octanoic and decanoic acid contents. The concentrations of non-esterified octanoic and decanoic acid in the portal blood increased slowly after the beginning of each infusion, reaching about 10 times higher values than the basal level. Only 26% of octanoic acid infused in the duodenum and 27% of decanoic acid were recovered in the portal flow throughout each experiment. The possible mechanisms underlying the appearance of MCFA in the portal blood in the absence of pancreatic enzyme secretions and the importance of duodenal absorption of MCT in such physiological conditions have been discussed.

The objectives of the study were to assess the 13C bicarbonate dilution technique using an automatic blood sampling system and to use this technique to estimate energy expenditure (EE) based on the CO2 production of 14 lactating Holstein cows on pasture or in a freestall barn. The effects of physical activity and eating behavior on EE were also assessed. Cows were exposed to each feeding system in a crossover design with two 14-d experimental periods, each consisting of an adaptation period and a 7-d data collection period. Cows either grazed on pasture or had ad libitum access, in the freestall barn, to grass cut daily from the same paddock. All cows were supplemented with a cereal-based concentrate. The EE of each cow was determined from 0700 to 1300 h on 1 d of each collection period. Blood samples for the 13C bicarbonate dilution technique were taken either manually in the barn or using an automatic blood sampling system on pasture. Eating pattern and physical activity were recorded from 0700 to 1300 h using a behavior recorder and an activity meter, respectively. Milk yield was recorded daily. Individual feed intake was estimated using the alkane double-indicator technique. Two preceding experiments confirmed that the sampling technique (manual or automatic) and the following storage of the blood samples (frozen directly after withdrawal or first cooled on ice and then frozen 6 h later) had no effect on 13CO2 enrichment in the extracted blood CO2 or on the subsequent calculation of CO2 production. During the 6-h measurement period, the EE of cows on pasture was higher than that of cows in the freestall barn. Daily feed intake and milk production were not affected by the feeding treatment. Grazing cows spent more time walking and less time standing and lying than did cows fed indoors. Time spent eating was greater and time spent ruminating was lower for cows on pasture compared with grass-fed cows in the barn. In conclusion, the 13C bicarbonate dilution technique, combined with an automatic blood sampling system, is a suitable method to determine the EE of lactating dairy cows on pasture. Positive correlations between EE and walking and eating time indicate that the higher energy requirements of dairy cows on pasture may be at least partly caused by a higher level of physical activity. However, before specific recommendations about additional energy supply can be given, it must be determined whether EE measured over 6 h can be extrapolated to 24 h. Furthermore, the apparent inconsistency between EE, feed intake, and milk production needs to be resolved.

International audience; We present a systematic theor. study of response properties of α-quartz SiO2 to an external static elec. field in the framework of the d. functional theory. The distortions of the electron d. and cryst. structure by the application of the field are investigated and compared to x-ray scattering intensity variations obtained by Guillot et al. when a macroscopic elec. field of 28.8 kV/cm is applied along the crystallog. a axis. Our calcns. show that the exptl. macroscopic field produces mainly at. displacements, with a negligible electronic contribution. The calcd. displacements along the a axis are in good agreement with the exptl. data obtained from structure factors while the perpendicular displacements are found to be smaller, as well as the rotations of the Si-O bonds in the two independent tetrahedra around the a axis. In this work, the direct gap, the high-frequency dielec. const. as well as the elastic and piezoelec. tensors are also computed in order to confirm the accuracy of our calcns.

Levodopa is the gold standard drug for the symptomatic control of Parkinson's disease (PD). However, long-term treatment with conventional formulations [levodopa and a dopa decarboxylase inhibitor (DDCI)], is associated with re-emergence of symptoms because of wearing-off and dyskinesia. Treatment with levodopa/DDCI and entacapone extends the half-life of levodopa, avoiding deep troughs in levodopa plasma levels and providing more continuous delivery of levodopa to the brain. In this open-label, retrospective, observational study we investigated the effects of levodopa/DDCI and entacapone therapy in 800 PD patients with motor fluctuations. Levodopa/DDCI and entacapone treatment was assessed as good/very good in improving motor fluctuations (64%) and activities of daily living (ADL; 62%). The therapeutic utility was considered to be good/very good in 70% of cases. Moreover, there was a reduction in levodopa dose in 20% of patients. Neurologists preferred levodopa/DDCI and entacapone compared with increasing levodopa dosage, dose-fractionation or addition of a dopamine agonist (63%, 29% and 23% of patients respectively). Reasons included achieving more continuous dopaminergic stimulation (40%), reducing motor fluctuations (54%) and improving ADL (41%). This analysis reveals the preference of neurologists for levodopa/DDCI and entacapone over conventional levodopa-modification strategies for the effective treatment of PD motor fluctuations in clinical practice.

A graftable LDV (Leu-Asp-Val) peptidomimetic molecule (B-c) has been prepared from 3-(5-amino-2-hydroxy)phenyl-propionic acid, as alpha(4)beta(1) (VLA-4) integrin ligand. For that purpose, the mechanism of 3-(4-azidophenyl)propionic acid rearrangement has been revisited. Activation of Durapore DVPP-hydrophilic membrane, by surface wet chemistry using triazine trifluoride, followed by covalent coupling of B-c produced a modified filter (0.8% of derivatisation from XPS analysis) with improved capacity of leukocyte retention.

It has been known for more than 30 years that the efficiency of the dopaminergic treatments can wear off. Currently, motor fluctuations and especially non-motor fluctuations (dysautonomic, cognitive/psychiatric or sensory/pain) remain often underdiagnosed in the first years of treatment. The patient self-questionnaire used in this study has been developed and validated in the United States. Its French version has been tested in daily practice in a study with 938 Parkinson's patients followed-up by movement disorders specialists. Use of this self-assessment patient card has resulted in the detection of fluctuations in 49% of patients, considered nonfluctuating by neurologists after a clinical assessment. The impact of these fluctuations unknown at first is significant, since these motor and/or non motor symptoms are considered troublesome or perturbing for daily life activities by 70% of fluctuating patients. The investigators have recognized the usefulness of this self-assessment in order to detect fluctuations in 81% of fluctuating patients, which lead them to modify the treatment in 76% of them.

Objectif La survenue d’une hypoglycemie profonde chez un patient doit faire rechercher, entre autre, une etiologie toxique. Un certain nombre de medicaments, insuline, hypoglycemiants oraux, antibiotiques, antalgiques peuvent etre responsables de cette perturbation metabolique. Nous relatons une observation d’intoxication medicamenteuse volontaire admise en hypoglycemie d’etiologie mal caracterisee. Observation Un patient de 56 ans, aux antecedents de paraplegie post-traumatique et d’intoxication medicamenteuse volontaire, est pris en charge par le Samu, qui constate un coma Glasgow 3 et une hypoxie (SpO 2 78 %). Deux boites vides d’Imovane ® sont retrouvees a cote de lui. Apres intubation, le patient est admis au service de reanimation. La glycemie au dextrometre revele une hypoglycemie a 0,25 g/L, confirmee par le laboratoire (1,4 mmol/L). Le traitement consiste en l’administration de 50 mL de glucose 30 % et du glucose 10 % (8 g/h pendant 19 h). Un remplissage vasculaire est necessaire (1,5 L) en raison d’une hypotension (88/50 mmHg). La paracetamolemie initiale etait de 17,7 mg/L. L’heure d’ingestion n’etant pas connue, un traitement par N -acetylcysteine est debute. L’evolution est favorable sans complication. Devant la divergence observee entre les effets attendus par rapport aux toxiques ingeres et l’existence d’une hypoglycemie, une autre cause toxique est evoquee. Le patient n’est pas diabetique, et il n’y a pas de personnes diabetiques dans son entourage. Les dosages d’insuline et de C -peptide sont normaux. Les dosages de metformine, de gliclazide, de glipizide, de glimepride et de glibenclamide par LC-MS/MS reviennent negatifs ( screening toxicologique et dosage de zopiclone non realises a l’admission). En reprenant le traitement medicamenteux a domicile, on retrouve la notion de prise chronique de tramadol. Le dosage du tramadol par LC-MS/MS apres extraction liquide-liquide met en evidence une concentration de 9,382 μg/mL (zone therapeutique 0,1 a 0,3 μg/mL), et vient confirmer notre hypothese. Discussion De plus en plus de publications font etat d’hypoglycemies induites par le tramadol a doses therapeutiques [1] . La survenue d’une hypoglycemie lors d’intoxications aigues est plus rarement signalee, souvent associee a l’ingestion de quantites importantes [2] . Deux mecanismes d’action sont evoques. Le tramadol a une action inhibitrice de la recapture de la serotonine qui provoque la liberation de β-endorphine en se fixant sur les recepteurs 5-HT7 et stimule ainsi l’utilisation du glucose au niveau du muscle. Mais c’est l’action du tramadol sur les recepteurs opiaces de type μ qui semble preponderante, comme pour le dextropropoxyphene, retire du marche en 2010. La concentration de tramadol retrouvee (9,382 μg/mL) est particulierement elevee : des concentrations letales sont signalees dans la litterature a partir de 2 μg/mL. La surveillance glycemique lors de coma d’origine toxique reste de mise. Conclusion Devant une hypoglycemie a priori toxique, il ne faut pas seulement evoquer la prise d’insuline ou d’antidiabetiques oraux, mais penser aussi a d’autres medicaments pouvant exercer un effet hypoglycemiant comme le tramadol, antalgique tres largement utilise.

International audience; The authors report the results of a comprehensive study on the structural, electronic, and optical properties of Ga2O3 in its ambient, monoclinic (β) and high-pressure, hexagonal (α) phases in the framework of all-electron d. functional theory. In both phases, the conduction band min. is at the zone center while the valance band max. is rather flat in the k space. The calcd. electron effective mass m*e/m0 comes out to be 0.342 and 0.276 for β-Ga2O3 and α-Ga2O3, resp. The dynamic dielec. function, reflectance, and energy-loss function for both phases are reported for a wide energy range of 0-50 eV. The subtle differences in electronic and optical properties can be attributed to the higher symmetry, coordination no. of Ga atoms, and packing d. in α-Ga2O3 relative to that in β-Ga2O3. [on SciFinder(R)]

cited By 45; International audience; The finite field approach has been implemented in the periodic ab initio CRYSTAL program and been used for calculating the dielectric constants of crystalline LiF and MgO (FCC structure) and BeO (wurtzite structure). To maintain the periodicity along the applied field direction, a "sawtooth" potential is used in conjunction with a supercell scheme. Supercells four to five times longer than the primitive cell in the direction of the applied field provide well-converged results. The influence of the computational parameters is discussed. An alternative scheme has also been implemented, for inner check, that consists of applying a static electric field to a slab of increasing thickness in the direction orthogonal to the surface; the dielectric response at the center of the slab is shown to converge rapidly to the bulk value evaluated with the sawtooth field. The method is accurate and permits the determination of nonlinear corrections to the dielectric constant. When used in conjunction with the local density approximation (LDA) scheme, it provides for the dielectric constant of the three above-mentioned compounds values close to those recently obtained with a time-dependent density functional theory approach.

International audience