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Compassionally reserved for inoperable patients in 2002, Transcatheter Aortic Valve Implantation has now a place almost equivalent to surgical valve replacement. The pioneering teams first succeeded in demonstrating a benefit on the mortality of extremely serious patients, while managing a learning curve that seemed unreachable without a strong partnership with cardiac surgeons. This win/win challenge enabled cardiologists to surpass the limits they did not dare to brave (management of large arterial approach, annular rupture and tamponade) and surgeons to appropriate the endovascular's culture. The technological contribution, the maturity of the teams and the expansion to less severe populations have reduced the perioperative mortality of TAVI to less than 3%. At this stage, it seemed interesting to take stock of forensic developments around this technique. After a review of the studies and the healthcare requirements, we reported and analyzed the claims received from one of the leaders of the medical insurance in France. From this feedback, attempts will be made to identify ways of improving the prevention and subsequent treatment of complications, which will undoubtedly limit the risk of subsequent complaints.

Introduction La granulomatose eosinophilique avec polyangeite (GEPA) est une vascularite necrosante des petits et moyens vaisseaux riche en eosinophiles associee dans environ 40 % des cas a la presence d’anticorps anti-cytoplasme des polynucleaires neutrophiles (ANCA). L’atteinte renale de la GEPA est moins severe et moins frequente que dans les autres vascularites a ANCA, estimee entre 15 et 25 %. Elle est peu decrite dans la litterature. Nous avons mene une etude observationnelle multicentrique de 63 patients presentant une atteinte renale prouvee histologiquement au cours de la GEPA. Patients et methodes Apres appel a observations, nous avons inclus les patients diagnostiques GEPA selon les criteres ACR 1990 et/ou les criteres modifies issus de l’etude MIRRA et ayant beneficies d’une ponction biopsie renale. Les caracteristiques cliniques, biologiques et histologiques ont ete recueillies au diagnostic et a la date des dernieres nouvelles. Resultats Soixante-trois patients (femmes 42,9 %, âge median au diagnostic de GEPA 60 ans) ont ete inclus. L’atteinte renale etait inaugurale chez 54 patients (86 %) et apparaissait au cours du suivi chez 9 patients (14 %) avec un âge median au diagnostic de l’atteinte renale de 63 ans (18–83). La duree mediane de suivi apres le diagnostic d’atteinte renale etait de 51 mois (1–296). Les ANCA etaient positifs chez 53 patients (84,1 %), dont 46 (86,6 %) etaient de type myeloperoxydase (MPO). Tous les patients avaient un asthme de revelation tardive. Quarante-huit patients (76,2 %) presentaient des signes generaux, 44 (69,8 %) une sinusite, 33 (52,4 %) des signes articulaires, 29 (46 %) une neuropathie peripherique, 25 (39,7 %) des signes cutanes, 23 (36,5 %) des polypes nasaux, 22 (34,9 %) une rhinite, 9 (14,3 %) une atteinte cardiaque specifique. Une hemorragie alveolaire etait rapportee chez 9 patients (18,4 %) sur 49 (donnee manquante chez 14 patients). Au diagnostic d’atteinte renale, il existait une insuffisance renale aigue chez 47 patients (74,6 %). La creatinine mediane etait a 180 μmol/L (75–1070). Il existait une proteinurie chez 60 patients (95,2 %) avec une mediane de 1 g/24 h (0,2–17,0) et une hematurie chez 53 patients (84,1 %). Cinq patients (7,9 %) ont necessite une dialyse d’emblee. Sur le plan histologique, on notait une glomerulonephrite extra-capillaire chez 50 patients (79,4 %), une nephrite interstitielle chez 39 patients (61,9 %), une glomerulonephrite extra-membraneuse chez 6 patients (9,5 %), la presence de granulomes chez 3 patients (4,8 %), une glomerulonephrite membrano-proliferative chez 2 patients (3,2 %), une angeite et une histologie compatible avec une maladie a IgG4 chez 1 patient (1,6 %) respectivement. Plusieurs patterns histologiques pouvaient etre associes. Sur le plan therapeutique, tous les patients ont recu une corticotherapie orale, precedee de bolus intraveineux chez 40 patients (63,5 %). Un traitement immunosuppresseur etait parfois associe en induction : cyclophosphamide chez 40 patients (63,5 %), rituximab chez 7 patients (11,1 %), echanges plasmatiques chez 6 patients (9,5 %). En traitement d’entretien, les donnees etaient disponibles chez 59 patients. Un traitement par azathioprine etait prescrit chez 28 patients (47,5 %), rituximab chez 9 patients (15,3 %), anti-calcineurine chez 5 patients (8,5 %), mycophenolate mofetil chez 4 patients (6,8 %), methotrexate et cyclophosphamide per os chez 2 patients (3,4 %) respectivement. A la date des dernieres nouvelles, 5 patients (8,1 %) etaient decedes : une hemorragie alveolaire, un cancer, un sepsis, et 2 de cause inconnue. Neuf patients (14,5 %) etaient en dialyse chronique, 2 (3,2 %) avaient beneficie d’une greffe renale. La maladie etait en remission chez 37 patients (60,7 %), refractaire chez 2 patients (3,3 %) et dependante au traitement chez 19 patients (31,1 %). La dose mediane de corticoides etait de 5 mg/j. Les donnees biologiques etaient disponibles pour 52 patients : la creatinine mediane etait a 115 μmol/L (53–222 μmol/L) avec une hematurie persistante chez 10/35 patients (28,6 %). Conclusion L’atteinte renale au cours de la GEPA est le plus souvent inaugurale chez des patients ayant des ANCA positifs de type MPO et un phenotype clinique vascularitique. Les anomalies du sediment urinaire sont associees a une insuffisance renale aigue en general moderee dans pres de trois quarts des cas. La glomerulonephrite aigue extra-capillaire est le pattern histologique le plus frequent, mais une nephrite interstitielle est presente dans plus de la moitie des cas et il existe des cas non exceptionnels de glomerulonephrite extra-membraneuse. L’evolution se fait souvent vers une insuffisance renale chronique moderee, mais le recours a une dialyse extracorporelle est parfois necessaire.

Recent column studies suggest that pesticide fate models could be used to estimate the fate of estrogens in soil. Estrogens are detected in livestock manure which is used as a nutrient source on agricultural land. This is the first study to examine estrogen mineralization in a wide range of agricultural soils at the regional-scale. Soil samples were collected from upper and lower landscape positions of 18 agricultural fields in an area spanning 49–60 °N longitude and 110–120 °W latitude and these samples were used to determine 17β-estradiol mineralization parameters in microcosm experiments. Maximum 17β-estradiol mineralization (Max) ranged from 5.8% to 19.2% and was, on average, significantly (P

Introduction Le pronostic de la maladie des anticorps anti-MBG a ete bouleverse par l’utilisation simultanee de corticoides, d’agents cytostatiques et d’echanges plasmatiques. Ce traitement entraine une diminution rapide, en moins de deux mois, du taux des anticorps anti-MBG qui disparaissent ensuite de la circulation. Malgre son origine auto-immune, l’utilisation du rituximab dans la maladie des anticorps anti-MBG est decrite dans de rares observations. Nous presentons cinq cas traites par la combinaison rituximab, echanges plasmatiques et steroides depuis novembre 2013. Observation La presentation clinique etait un syndrome pneumorenal pour deux patientes (F 18 et 63 ans), une atteinte renale isolee pour deux autres (H 73 ans et F 75 ans) et enfin une atteinte pulmonaire isolee (F 75 ans). Les DFG initiaux etaient respectivement a 4 et 8 mL/min en cas de syndrome pneumorenal, 5 et 14 mL/min (5 mL/min a j + 8) en cas de d’atteinte renale isolee. Trois biopsies renales ont ete realisees (refus dans un cas) retrouvant des lesions extracapillaires touchant entre 90 et 100 % des glomerules. Une patiente avec syndrome pneumorenal a ete ventilee et hemodialysee, et deux autres ont ete hemodialysees d’emblee. Les anticorps anti-MBG etaient detectes en IFI dans tous les cas. Les ANCA de specificite MPO etaient presents chez la patiente âgee de 63 ans avec atteinte pulmonaire et renale. L’induction par rituximab a suivi le schema 375 mg/m2/sem × 4 semaines, excepte pour un patient qui a recu trois administrations (H 73 ans hemodialyse d’emblee). Les echanges plasmatiques etaient poursuivis jusqu’a la negativation des anti-MBG : 17 seances en moyenne (9–23). Les anticorps anti-MBG se sont negatives en moyenne au bout de 22 jours (9–29). Les atteintes pulmonaires ont gueri ; les atteintes renales ont conduit les patient vers l’epuration extrarenale. Un a ete depuis transplante. Conclusion La negativation des anti-MBG est obtenue en associant le rituximab aux echanges plasmatiques et aux steroides, dans un delai superposable a celui attendu avec le cyclophosphamide. Le rituximab pourrait etre utile en cas d’intolerance a ce dernier.

Percutaneous suture closure devices have reduced the time needed for manual compression and hospital stays, but several meta-analysis emphasized a higher risk of vascular damages compared to manual compression. Two cases of infections on percutaneous suture closure devices were analyzed; which had medico-legal issues. Beyond the medical point of view, the patient's complaints, the way lawyers and medical experts have examined the cases were analyzed and resulted in physicians and hospitals being sentenced. Rather than stigmatizing those devices, we just want to invite cardiologists not to underestimate this serious risk. Before using those devices, physicians should balance the risk-benefit ratio, follow prevention guidelines, and most of all, be aware of any single signs of emerging infection to detect and treat them early, and thus reduce the severity of infections thanks to a targeted antibiotic treatment adapted to the antibiogram and an active role of vascular surgeons.

The crystal structures at 30 K of two iron(II) complexes, and their comparison with higher temperature crystal structures indicate that, outside of the spin transition range, the only intramolecular modification comes from dynamical aspects. The contraction of the packing is strong from 110 to 30 K and similar in both complexes. The high pressure (0.16 GPa, 0.40 GPa) crystal structures of another iron(II) complex of the same family show that strong changes are induced under pressure within the packing but that, to a first approximation, the effects of temperature (11 K) or pressure (0.40 GPa) on the intermolecular contacts are very similar even though one S···C intermolecular contact is significantly different. Moreover, slight differences in the cell parameter changes are noted. We also show that the deformation of the iron(II) coordination sphere does not depend on the applied constraint but on the spin state only.

The crystal structure of (TMTSF)2ClO4 has been determined at (7 K, 1 bar) and at (7 K, 5 kbar) with a high accuracy. For the latter, low temperature and pressure were applied simultaneously using a X-ray diffraction instrumentation designed in our laboratory, these results are the first for molecular compounds. The effects of lowering the temperature are not the same as those produced by increasing the pressure. At (7 K, 1 bar) the anion ordering which occurs in this compound, and which is characterised by the appearance of b * /2 superlattice reflections, is well observed. This anion ordering leads to the presence of two independent stacks of TMTSF cations which is the only case found in the Bechgaard salts family. The comparison of the low temperature crystal structures under atmospheric pressure and at 5 kbar shows that the centres of mass are nearly the same, independent of the pressure: the interchain interactions do not depend on the doubling of the unit cell. Under pressure, the ordering (0, 1/2, 0) does not occur at any temperature. These structural data are confirmed by the quantum chemical calculations which show that the difference in the site energy of the two independent cations is 100 meV.

The X-ray crystal structure of (BEDT-TTF)3Cl2·(H2O)2 [BEDT-TTF=bis(ethylenedithio)tetrathiafulvalene] has been determined at 190, 130, and 10 K. The broad metal–insulator transition (100–160 K) observed in the resistivity data at ambient pressure, and the pressure induced superconductivity (Tc=5 K at 1.2 GPa) can be associated with temperature-dependent motion of the molecules within the unit cell and charge redistribution among the three independent BEDT-TTF molecules. The motion can be considered as a dimerization of the BEDT-TTF along the a-axis. The thermal expansion tensor in the range 12 to 295 K is anisotropic and reveals no sharp anomaly. The system remains two dimensional at all temperatures, in agreement with the electrical conductivity measurements.

Electrocrystallization of CH2Cl2 solutions of Cp2Mo(dmit), dmit2- = 2-thioxo-1,3-dithiole-4,5-dithiolate, in the presence of n-Bu4NX (X- = PF 6 - , AsF 6 - , SbF 6 - ) affords the corresponding 1:1 cation radical salts [Cp2Mo(dmit) ][X-]. The three isostructural salts crystallize in the orthorhombic system, space group Cmcm. In the three salts, a second-order transition at a temperature T1, identified by EPR measurements and low-temperature X-ray Weissenberg photographs reveals also a splitting of some principal reflections and the twinned character of the crystals, whose room temperature structure may also be described in the monoclinic P21/m space group. The second order monoclinic triclinic transition is associated with the apparition of a superlattice characterized by the critical wave vector when expressed in the monoclinic system. A second transition at a lower temperature T2, of first order character, is observed only in the PF 6 - salt. This triclinic triclinic transition leads to a novel superlattice of wave vector while the superlattice is conserved down to 10 K in the AsF 6 - and SbF 6 - salts. Finally, a third transition to an antiferromagnetic ground state is observed for the three salts and investigated by static susceptibility measurements and Antiferromagnetic Resonance (AFMR) experiments. The detailed analysis of the AFMR rotation patterns confirms the twinned nature and the low temperature triclinic symmetry of the crystals as well as the peculiar behaviour of the PF 6 - salt, when compared with the two other members of these novel series.

The effect of the first-order phase transition occurring around 220K on the crystal and electronic structure of the molecular superconductor (BEDO-TTF)2ReO4·H2O has been studied. The crystal structure at 170K has been determined and it is found that the main structural change resulting from the phase transition is connected with a rotation of the ReO4− anions. This rotation leads to changes in the S…S and S…O intermolecular contacts within the BEDO-TTF donor layers, nevertheless the band structure is remained practically unchanged. Possible changes in the crystal structure which can occur at room temperature depending on the experimental conditions are considered. It seems very likely that the (BEDO-TTF)2ReO4·H2O crystal loses its water molecules in the vacuum and hence changes its crystal structure.

The physical properties of paramagnetic Mo(V) organometallic radical cation salts, , are investigated through the study of two series of solid solutions incorporating two kinds of anions ( or ). The combination of EPR and X-ray diffraction is used to specify the nature of the structural phase transitions which occur in the paramagnetic phase and to determine the corresponding ( T , x ) phase diagrams. Finally, antiferromagnetic resonance is studied to probe the low temperature antiferromagnetic ground state. In the last part of the paper, the observed complex phase diagram is analyzed by considering a compressible model with at least two independent modes of compression. We conclude that the larger compressibilities are associated with the smaller anions.

([2H8 ]BEDT–TTF)4Cl2 ·6D2O [BEDT–TTF=bis(ethylenedithio)tetrathiafulvalene] exhibits a transition from semimetal to semiconductor at T=160 K (Rosseinskyet al., J. Mater. Chem., 1993, 3, 801). This electronic transition is accompanied by a structural transition that is characterized by the reversible appearance of superstructure reflections corresponding to the doubling of the cell parameter b and a change in space group from Pcca to Pbcn. The crystal structures are very similar above and below T and the calculated intermolecular transfer integrals scarcely change. In contrast, from the difference in intramolecular bond lengths, it is clear that the two crystallographically independent BEDT–TTF molecules carry different charges at low temperature, suggesting that a degree of ionicity arising in the BEDT–TTF layer is responsible for the change in electrical behaviour.

Le sel (BEDT-TTF)3CuBr4 (BEDT-TTF: bis(ethylenedithio)-tetrathiofulvalene) presente une transition entre deux etats semi-conducteurs qui s'accompagne d'une perte de susceptibilite magnetique a 60 K. L'application d'une pression engendre l'augmentation de conductivite la plus importante observee dans les conducteurs organiques et induit une transition vers un etat metallique a 5 kbar. L'etude structurale en temperature (10 - 295 K) montre que la localisation de la charge sur l'un des deux cations cristallographiquement independants presente a temperature ambiante disparait a 10 K et prouve que l'anion CuBr 4 2 - reste de geometrie plan carre contrairement a ce qu'une distorsion de type Jahn-Teller suggeree par RPE pouvait laisser penser. L'etude structurale a haute pression (0-15 kbar) confirme que le caractere monocristallin des cristaux organiques peut disparaitre par application de pression. Les espaces intermoleculaires sont considerablement reduits a 10 kbar en accord avec l'evolution de la conductivite. Au regard de ces resultats, les proprietes physiques de ce sel paraissent devoir etre reexaminees.

The crystal structure of α′-(BEDT–TTF)2Ag(CN)2[BEDT–TTF = bis(ethylenedithio)tetrathiafulvalene], which exhibits a spin-Peierls (at 7 K) and a semiconductor-semiconductor transition, was determined above and below the latter phase transition at 8 kbar (295 K) or 260 K (1 bar) by single crystal X-ray diffraction. The structural transition has been studied both by increasing pressure at 298 K and by lowering temperature at ambient pressure. It is characterized by the doubling of the b parameter and it is accompanied by a charge transfer from molecule to molecule, resulting in nonequivalent BEDT–TTF molecules alternating along both a- and b-axes. The crystal has the same isothermal compressibility above and below the transition with a limiting bulk modulus (Kv–1) of ca. 190 kbar. The structural behaviour of this salt is similar to that of the isomorphous α′-(BEDT–TTF)2AuBr2, which also shows a spin-Peierls transition.

([2H8]BEDT-TTF)4Cl2·6D2O [BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene] has been obtained as long black needles by electrocrystallisation of [2H8]BEDT-TTF in CH2Cl2 in the presence of [(C2H5)4N]Cl·D2O. It crystallises in the orthorhombic space group Pcca, a= 32.575(2)A, b= 6.709(1)A, c= 14.854(2)A, V= 3246(1)A3 and Z= 2. The structure consists of twisted (dihedral angle of 29°) pairs of crystallographically equivalent BEDT-TTF cations forming stacks parallel to c with close intermolecular S ⋯ S contacts along b, resulting in layers. A layered network of chlorine and water molecules linked by weak hydrogen bonds alternates with the layers of organic donor molecules. The conductivity parallel to b is 40 S cm–1 at 300 K, almost constant with decreasing temperature to ca. 160 K. Below 150 K the conductivity shows a temperature-dependent activation energy, ranging from 14 meV at 140 K to 6 meV at 10 K. It increases linearly by a factor of 3 by applying a pressure up to 24 kbar; the transition temperature decreases from 160 to 20 K. The anisotropy of the microwave conductivity is 0.5:240:3.6 S cm–1. The spin and static susceptibilities measured, respectively, by electron paramagnetic resonance (EPR) and Faraday magnetometry are temperature independent between 70 and 300 K, and obey a Curie–Weiss law below 50 K with θ=–4 K. The calculated band structure and Fermi surface show twodimensional character of both electron and hole pockets, with the possibility of 2kF nesting.

[4′-(Dimethylamino)biphenyl-4-yl]dimesitylborane (BNB) and 4-[4′-(Dimethylamino)pnenylazo]phenyldimesityl-borane (BNA) have been investigated by X-ray diffraction; crystallographic data were used to calculate dipole moments in the ground state and the hyperpolarizability coefficient βo was measured by the EFISH technique for each derivative. The results show that the trivalent boron group is an efficient electron acceptor compared to other known acceptors such as the nitro group. Organoboron derivatives are promising candidates for nonlinear optical materials.

The synthesis and physical characterization of a complex of BEDT-TTF [bis(ethylenedithio)tetrathiafulvalenium] with Cu II Cl 4 2- are reported. The structure of (BEDT-TTF) 3 CuCl 4 .H 2 O (I) (crystal data: triclinic, space group P1, a=16.634 A, b=16.225 A, c=8.980 A, c=90.72 o , β=93.24 o , γ=96.76°, V=2402 A 3 , Z=2) consists of alternating layers of organic cations and inorganic anions.

[Fe(C 9 H 19 )(C 5 H 5 )](C 12 H 4 N 4 ) 2 cristallise dans P2 1 /m avec a = 7,914, b = 30,983 et c = 6,629 A, β = 102,38 °, Z = 2; affinement jusqu'a R = 0,042. La structure consiste en couches de TCNQ separees par le ferrocene. Les effets steriques des groupes methyl ne se manifestent pas seulement sur le metallocene, mais egalement sur l'empilement du TCNQ.

In this paper are presented two modifications of hydrated chlorides of bis(ethylenedithio) tetrathiafulvalene (BEDT-TTF)xCl2, yH2O with stoichiometries x=3, y=2(I) and x=4, y=6 (III). The room temperature crystal structure of (I) the 3/2 stoichiometry and (II) the 4/4 stoichiometry compounds were already known. (I) has been measured at low temperature (50K) to look for the structural changes associated with the variations of the physical properties near 110K. The latter has been correlated with the modification of the thermal expansion anisotropy in the stacking direction of BEDT-TTF cations, the [010] crystallographic direction. The new 4/6 salt (III) is the third hydrated BEDT-TTF chloride known up to date. It differs from the others by the space group. As for the precedent forms one can see a 2D arrangement of anionic and cationic sheets alternating along the [100] crystallographic direction, but there are two orientations for the BEDT-TTF planes and two kinds of overlapping modes of these molecules.

Conducting organometallic salts based on tetracyanoquinodimethane (TCNQ) and metallocenes of iron, (Cp)Fe(Ar), where the metal is complexed by two rings: cyclopentadienyl (Cp) and substituted benzen ring (Ar), have been synthesized with the following arene ligands: Ar = C 6 H 6 , C 6 H 5 Me, C 6 H 5 Cl, C 6 H 3 Me 3 , C 6 H 3 (tBu) 3 , C 6 Me 6 and C 6 Et 6 . The magnetic behaviour is characteristic of linear chains of S = 1 2 spins (the metallocene cations are diamagnetic). A steric effect, due to the substituents carried by the benzen ring, is observed, which induces changes in intrastack distances between TCNQ molecules and, therefore, in the antiferromagnetic exchange coupling: the larger the substituent size, the lower the AF exchange coupling constant J.

We report the compressibility tensor calculated from the pressure dependence ( The magnitudes of the principal compressibilities ki decrease very slightly and the bulk modulus strongly increases with increasing pressure. k2 is along the crystallographic b axis. Thus, the directions of the smallest(k3) and largest (k1) are in the ac plane; on the projection along the b axis, k3 is parallel to the long axis of the molecule and corresponds to the maximum density of atoms. The crystal structure of a twinned crystal has been refined to R = 0.095. Using the atomic coordinates, the transfer integrals have been calculated; the comparison of the high and ambient pressure band structures shows that the two-dimensional character of this compound is enhanced by pressure.

The physical properties of the new complex and mixed salt (TMA+)3(I − 3 ) (TCNQ−)2(TCNQo) characterized recently are presented. Crystallographic study at room temperature has shown a diffuse scattering which indicates the existence of a 1-D superlattice. From dynamic (EPR) and static magnetism investigations and the existence of a specific heat anomaly an electronic PEIERLS distorsion is postulated. However the semi conductive behaviour of this salt is evidenced by the d.c. conductivity and the thermoelectric power results. A comparison with similar situations in TTF-TCNQ and mainly in KCP is presented.

In this paper, we discuss an irreversible phase transition occuring in the TCNQ salt which diethylcyclohexylammonium cation : DECA (TCNQ)2, when heated above 350 K. The transition, which is of first order as evidenced by heat capacity measurements, is accompanied by very large discontinuities in properties such as magnetic susceptibility and d. c. electrical conductivity. The phase diagram [P = f(T)] has been determined, as well as the crystal structures of both phases. The observed structural transformation allows us to explain the temperature behaviour of the physical properties.

The crystal structure of the title compound, tris[3,4,3',4'-bis(ethylenedithio)-2,2',5,5'-tetrathiafulvalene] tetrabromocuprate(2−), (C 10 H 8 S 8 ) 3 [CuBr 4 ], is classified as the α phase and contains two independent BEDT-TTF [BEDT-TTF = 3,4,3',4'-bis(ethylenedithio)-2,2',5,5'-tetrathiafulvalene] molecules (A and B) stacked as ABBABB along the c axis. The dihedral angle between the A and B molecules is 5.3 (1)° and between the stacks is 67.1 (2)°. The shortest intermolecular distances observed between molecules in adjacent columns are S...S 3.485 (2) and S...C 3.428 (4) A, and between anions and cations Br...S 3.777 (1) A

BACKGROUND: Endothelin- (ET-1) is involved in the pathogenesis of several ischemic diseases. We investigated the hypotheses that ET-1 is involved in the pathogenesis of experimental critical hind limb ischemia and that ET-1 receptor antagonists have a protective effect. MATERIALS AND METHODS: Critical hind limb ischemia was achieved by exclusion of the femoral artery and embolization of collateral vessels in rats. The induction of endothelin system components by ischemia was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) (mRNAs) and immunoassay (peptides) in the plasma and ischemic muscles 5 hr (H5), 5 days (D5) and 14 days (D14) after ischemia. Two groups of rats received 100 mg/kg/day of either Bosentan, a mixed ET(A/B) receptor antagonist (n = 12), or LU 135252, a selective ET(A) receptor antagonist (n = 9), and a control group without treatment (n = 12) served as control. Muscle blood flow and ischemia were monitored in the ischemic limb by laser Doppler and phosphorylase activity, respectively. RESULTS: The procedure induced an 80% decrease in muscle blood flow and complete suppression of phosphorylase activity without necrosis. At day 14, the tissue blood flow remained reduced by 70% and phosphorylase activity was suppressed completely. There was up-regulation of preproendothelin-1, preproET-3, endothelin converting enzyme-1, and ET(A). ET(B) receptor mRNAs in ischemic muscle at day 5 and day 14 was accompanied by an increase in muscle concentration of ET-1 at day 5, without significant changes in plasma endothelin. Treatment with Bosentan and LU 135252 increased tissue blood flow and reduced muscle ischemia at day 14. CONCLUSIONS: Tissue production of ET- 1 is up-regulated in experimental critical hind limb ischemia. Inhibition of the endothelin system by a mixed ET(A/B) receptor antagonist may protect, at least in part, against muscle injury.

High pressure single crystal X-ray diffraction experiments have been performed in the range 0-13kbar on the ironˆ (II)complex Fe(Phen)2(NCS)2 which exhibits a spin transition at Tc =176K and ambient pressure or at room temperature and Pc =6kbar. Compressibility data show a change of derivative in the unit cell volume V around 5. 8kbar. A full X-ray structure determination was performed at a pressure of 10kbar: the molecular conformation is found to be characteristic of the low spin form, close to the one already observed at low temperature (T =135K) and ambient pressure.

Cristallisation dans Pī avec a=7,8665, b=7,8575, c=13,4458 A, α=95,67, β=101,36, γ=111,08°, z=2; affinement jusqu'a R=0,0489. Les cations organiques DMCTTF + s'empilent le long de l'axe a, selon un mode de type zigzag. Ils forment des colonnes conductrices de dimeres faiblement lies. Les anions AsF 6 - sont localises dans les cavites, laissees par les molecules organiques. Les atomes As sont situes sur le centre d'inversion de leur octaedre

Hitherto, formation of new blood vessels was usually classified into two well-known embryological phenomenons: vasculogenesis and angiogenesis. Vasculogenesis is described as a primary in situ differentiation of endothelial cells from mesodermal precursors, leading to the formation of primary capillary poleaxe. Angiogenesis was thought to be exclusively the result of vessels’ sprouting from pre-existing vessels. But recently, Asahara et al. have showed that circulating endothelial cell progenitors are also involved in the angiogenic process [1]. Concerning collateral vessel formation, a third concept, called “arteriogenesis” has been introduced by Schapper [2]. It consists of the remodeling of small capillaries into larger arterioles, with a muscular layer. Nevertheless, those three entities require: proliferation and migration with a spatial organisation of endothelial cells dissolution and regeneration of the vascular extracellular matrix, considered as vascular stake participation of mesenchymal perivascular cells (smooth muscle cells and pericytes) .

Jeune syndrome (asphyxiating thoracic dystrophy) is a rare inherited disease which is fatal in early childhood in 70% of cases. Severe renal involvement may occur and lead to chronic renal insufficiency in patients who survive respiratory failure. Therefore the opportunity to perform kidney transplantation is quite rare. We report a successful cadaver renal transplantation in a 10-year-old boy with Jeune syndrome type 2.

Summary form only given. The molecular charge-transfer salt (BEDT-TFF) /sub 3/Cl/sub 2/,2H/sub 2/O undergoes a metal-insulator transition at about 100K and becomes superconducting under pressure (10kbar) at 5K. The isobaric thermal expansions are calculated from the values of the lattice parameters (300 to 12K at ambient pressure). The electronic properties are deduced from the ambient pressure (295, 130 and 12K) crystal structures.

Summary form only given. The molecular charge transfer salt /spl alpha/-ET/sub 2/Ag(CN)/sub 2/ undergoes a structural phase transition, between two semi-conducting phases, whose critical temperature, near to 300K, depends on pressure. This transition is cristallographically characterised by the appearance of 1/2 b* superlattice reflections at high pressure or low temperature. The isobaric thermal expansions and the isothermal compressibilities are calculated from the values of the lattice parameters (330 to 85K at ambient pressure; ibar to 12.4 kbar at room temperature). The electronic properties are deduced from, the ambient pressure (295 and 120K) and room temperature (5.4, 8 and 1 1kbar) crystal structures.

The ordering of the anion in the molecular conductor salt (TMTSF) 2 NO 3 at low temperature depends on the rate of cooling and corresponds to the doubling of the a cell parameter. This order-disorder transition does not affect the crystal packing as the TMTSF chains in the ordered and in the disordered crystal structures at 12K can not be distinguished. This salt is strongly 1D at low temperature.

The anion ordering which occurs in (TMTSF) 2 ClO 4 at 24 K is characterized by the appearance of b * /2 superlattice reflections, without any important change in the basic crystal structure. The intensities of these superlattice reflections have been measured at 7 K (ambient pressure). At the same temperature, these reflections do not appear under pressure (5 kbar). Thus, in the latter case, the anions remain disordered.

The low temperature crystal packing of (TSeT) 2 Cl is similar to that obtained at room temperature, no structural transition occuring. Only small changes in the atomic parameters are observed. On the contrary, the high pressure and the high pressure-low temperature crystal structures show a change in the symmetry which leads to a difference in the network of the chloride anions and in their environment.

The magnetic molecular semiconductor (BEDT-TTF) 3 CuBr 4 exhibits a phase transition at 60K accompanied by an abrupt fall in magnetic susceptibility and also shows a transition to a metallic state at 5kbar. The temperature dependence of the crystal structure (10–298K) reveals a change in the charge distribution on the cation while the variation of the structure with the pressure (0–16kbar) shows that the intermolecular empty spaces are strongly reduced.

The temperature and pressure dependence of the electrical conductivity of the α'-(BEDT-TTF) 2 Ag(CN) 2 salt shows a transition between two semiconducting phases at a critical temperature depending on pressure. This transition is crystallographically characterized by the appearance of a superstructure corresponding to the doubling of the b parameter. We present and discuss here the parameters evolution at decreasing temperature and increasing pressure and the structural evolution under constraints.

The neutron (1. =1.1750A) high pressure (7 102MPa) and low temperature (1.7K) structure of (TMTSF)2PF6 (Di(2,3,6,7-tetramethyl-1,4,5,8-tetraselenafulvalenium hexafluorophosphate; 2(C10H12Se4)1/2+, PF6 −, Mr=1041.06) is reported. The lattice is triclinic P and cell parameters: The geometry of the Tmtsf stacks changes little under constraint exception made for a shortening in the interplanar spacing. For the titled compound at 7 102 MPa a temperature decrease from 300K to 4K is equivalent to the effect of an extra 2 102MPa applied pressure. However temperature (rather than pressure) is responsible for a small change in the transverse shift of adjacent Tmtsf molecules in a same column. Similarly pressure has little effect on the PF6 − anion disorder at a given temperature. If the low temperature TMTSF packing of (TMTSF)2PF6 (superconducting below ≃ 1.2K and above 9.5 102 MPa) is compared to that of (Tmtsf)2 C104 (superconducting below ≃1,2K at ambient pressure), the intrachain interactions are found...

s Service): alors que bis(trim6thyl6ne)-3,4;3',4' tr Spencer, Cava & Garito, 1976) et l'influence de la perte de symr la temperature de transition est 81 K. Un signal RPE de grande largeur laisse pr6voir des interactions tridimensionnelles fortes, plus fortes que celles pr6sentes dans les cristaux de T T F T C N Q et H M T T F T C N Q (hexam&hyl+net6trathiafulval6ne-t&racyanoquinodim6thane). 2812 TRIMETHYLENETETRATHIAFULVALENE-TETRACYANOQUINODIMETHANE Partie exp6rimentale