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We have studied aspects of the regulatory interrelationship between the plasma membrane oxidoreductase (PMOR) system and the mitochondrial respiratory capacity of human Namalwa cells. Although the role of mitochondria in the maintenance of cellular redox and energetic states is well established, the PMOR system in comparison is a poorly characterized enzyme system whose functions, particularly in relation to cellular metabolism, have not been clearly elucidated. Therefore we compared the PMOR and mitochondrial respiratory activities of human Namalwa cells during the induction by ethidium bromide treatment of rho 0 cells, which lack a functional mitochondrial respiratory system. The plasma membrane NADH-ferricyanide reductase activity of the PMOR system was found to increase in a stepwise manner concomitant with a decline in cellular mitochondrial respiratory activity. Addition of p-chloromercuriphenylsulfonic acid to the culture medium, at a concentration totally inhibiting the plasma membrane NADH-ferricyanide reductase in vitro, leads to cell death of rho 0 but not of rho + cells. Thus, the up-regulation of a functional PMOR system is a necessary phenomenon in maintaining the viability of mammalian rho 0 cells.

Increasing use is being made of colorimetric assays to quantitate viable cells, e.g., the cellular reduction of the tetrazolium salt, MTT, to formazan by mitochondrial succinate dehydrogenase. We validated this assay for cell proliferation in mixed lymphocyte cultures as compared with 3H-thymidine uptake, and for inhibition of cell proliferation induced by interferon with results compared by direct cell counting. We also found that cells do not, as previously assumed, require functional mitochondria: there were no differences in formazan production by normal cells or respiratory defective cells in which mitochondria had been poisoned by the nucleic acid toxin, ethidium bromide. The high reproducibility of MTT metabolism by lymphoblasts and various cultured cell lines establishes the reliability and versatility of this method for quantitating cell numbers.

Using cultured lymphoblastoid Namalwa cells, we have demonstrated that humans cells can be grown for long periods in the absence of oxygen. Such anaerobic growth occurs at the same rate as that of aerobic cultures, but is characterized by a strict dependence on pyruvate. Cells in anaerobic culture undergo a severe loss of mitochondrial cytochromes, that is reversible on reaeration. Anaerobically grown cells show a two-fold increase in glucose consumption, consistent with anaerobic glycolysis providing the source of ATP for cellular maintenance and growth. The requirement for pyruvate is explained by the necessity for these cells to re-oxidise NADH derived from metabolic reactions. Detailed study of anaerobically grown human cells provides a new framework for investigating tissues depleted in mitochondrial functions, as occurs in mitochondrial diseases and the ageing process.

Introduction et but de l’etude Le travail de collaboration de notre CLAN avec l’Unite d’Exploitation de l’Information Medicale (UEIM) a permis de demontrer l’interet de coter la denutrition comme comorbidite associee (CMA) pour la valorisation de l’activite (Journees Francophones de Nutrition 2006). La poursuite de notre etude visait a : 1 – Mesurer l’impact financier de la cotation de la denutrition dans une unite medicale ou le risque de denutrition est eleve et ou la presence d’autres CMA pouvait annuler l’interet de la cotation de la denutrition 2 – Etudier l’influence de la denutrition sur la duree moyenne de sejour dans les pathologies avec CMA 3 – Etudier l’influence de la denutrition sur la duree moyenne de sejour dans les pathologies sans CMA (la denutrition n’entraine pas systematiquement une CMA). Materiel et methodes Etude de l’impact financier de la cotation « denutrition E43 a E46 » en onco-hematologie (janvier a mars 2007). Comparaison, dans toutes les unites du CHU, de janvier a mai 2007, des durees de sejour (test de Kruskal-Wallis). Resultats 1) En onco-hematologie, sur 350 sejours, 111 (32 %) ont ete cotes en denutrition et sur ces 111, 47 presentaient une valorisation potentielle liee a la denutrition (une CMA n’entraine pas systematiquement une valorisation). Sur ces 47 sejours, en un seul trimestre, 18 ont permis une valorisation de 68 500 grâce a la denutrition (sans autre CMA associee). 2) Sur l’ensemble du CHU, de janvier a mai 2007, on retrouve 5 343 sejours avec CMA, dont 419 CMA liees a la denutrition. La mediane de la duree de sejour etait de 15 j (moyenne 19,2 j) dans le groupe avec denutrition et de 9 j (moyenne 13,2 j) dans le groupe avec CMA autre que denutrition (p 3) Sur l’ensemble du CHU, de janvier a mai 2007, on retrouve 12339 sejours sans CMA, dont 212 avec denutrition. La mediane de la duree de sejour etait de 8 j (moyenne 13,8 j) dans le groupe avec denutrition et de 4 j (moyenne 6,3 j) dans le groupe sans denutrition (p Conclusions Dans les sejours avec CMA, la duree mediane de sejour est significativement plus allongee lorsque la CMA retenue est la denutrition. Il en est de meme lorsqu’il y a denutrition dans les sejours sans CMA declaree. Enfin, la denutrition declaree systematiquement entraine une valorisation, meme dans un service de soins a comorbidites nombreuses.

Dans les Hautes-Pyrenees, 29 especes de Clinocerini sont signalees, dont 24 ont ete decrites anterieurement. L'une des 29 especes, ainsi que 4 autres especes nouvelles des Pyrenees-Atlantiques, sont decrites ici. Les caracteres d'une espece mal connue sont precises.

A simple model of recombination at dangling bonds in a-Si:H is proposed to explain the steady-state photoconductivity and \ensuremath{\gamma}-exponent variations with the equilibrium Fermi-level position. The appropriate statistics for correlated defects and the Shockley-Read formalism are used to obtain a parametrical representation of photoconductivity versus optical generation rate. Oscillations of \ensuremath{\gamma} between 0.5 and 1 when ${E}_{F}$ is shifted in the central region of the gap depend mainly on the density of dangling bonds and the energy positions of the singly (${T}_{3}^{0}$) and doubly (${T}_{3}^{\mathrm{\ensuremath{-}}}$) occupied levels. Experimental results on lightly-boron-doped glow-discharge a-Si:H are in agreement with the model and give a location of the ${T}_{3}^{0}$ level at 0.95 eV from ${E}_{c}$, an effective correlation energy of 0.4 eV, and a ratio of charge-to-neutral-state capture cross sections of 50. Finally, the dangling-bond-state occupation probabilities are shown to be weakly modified by illumination even at high photon fluxes. Consequences for the interpretation of ESR experiments are also discussed.

CeRu2 is a superconductor at low temperatures and its hydride exhibits strong magnetic correlations on a macroscopic scale. Neutron diffraction experiments provide evidence for magnetic ordering, in agreement with the occurrence of a transition from Ce4+ to Ce3+ on hydriding.

Une nouvelle espece de Dipteres Thaumaleidae est decouverte dans les Pyrenees et vient s'ajouter aux six autres connues de cet ensemble montagneux ; elle est proche d'une espece du centre de l'Espagne.

Thin films of a-Sb 2 S 3 were prepared by thermal evaporation. Many experimental parameters usually related to electronic disorder were studied, such as the exponent of the photoconductivity and the optical absorption edge. The results suggest that the defects in this material induce a density of states with exponential band tails.

The structural and magnetic characteristics of RE 2 Fe 14 BH x hydrides with RE ≡ Y, Ce, Er have been studied as a function of x . Both Curie temperature and magnetization are increased on hydriding the ternary bondes. Neutron diffraction experiments performed on deuterated samples have permitted the location of the host sites and the measurement of the magnetic moments of iron and RE. Different anomalies reported in the structural and magnetic behaviour of Ce 2 Fe 14 BH x are related to the change of electronic state on cerium.

The theory of recombination at dangling bonds and band tails is developed. The statistics for correlated defects are included and the Shockley-Read formalism is extended to asymmetric exponential distributions of tail states. Parametrical representations of the photoconductivity and the charge densities are obtained. A comparison of the results explains the thermal quenching of the photoconductivity experimentally observed. At low temperatures, the photoconductivity is determined by the balance between the two band- tail charge densities. At higher temperatures, one band-tail density becomes negligible compared with the dangling-bond charge density and the photoconductivity is controlled by the latter. Finally, the variations in photoconductivity with the density-of-states parameters are discussed. The agreement between the model and experimental results on undoped hydrogenated amorphous silicon is excellent for temperature above 150K. The divergence observed below 150K can be interpreted with ca...

The Fermi level effects on photoconductivity σ ph are analysed experimentally on boron doped sputtered and glow discharge samples with well-characterized boron contents, optical properties and gap defects densities. The results on σ ph and its exponent γ in SP materials indicate that the recombination kinetics are controlled by the valence band tail states profile according to Rose's model whereas in GD materials these are controlled by the position of E F relative to one single defect placed at E i − 0.05 eV with positive correlation energy.

The spontaneous oxidation of plasma-deposited hydrogenated amorphous silicon (a-Si:H) was analysed using spectroscopic ellipsometry. The influence of the temperature was studied up to 300°C. a-Si:H was found to be remarkably resistant to surface oxidation. An extremely slow growth of the oxide film on dense material was observed at room temperature; the oxide layer obtained after prolonged exposure was found to be 6 A thick. When the material was porous, the internal surfaces of the void network located near the free surface slowly oxidized in air.

Des representants de 10 especes de Psychodinae ont ete recueillis au Liban ; 4 d'entre elles ont une vaste repartition en Europe et meme en dehors de ce continent ; 5 autres especes sont nouvelles et chacune d'entre elles est proche d'une espece de la partie occidentale de l'Europe.

The polarization state of an X-ray beam diffracted by a mosaic crystal is determined. The state of the incident beam being described by four Stokes parameters, the matrix method used allows the calculation of the Stokes parameters of a monochromatic X-ray beam and it leads to a general expression of the polarization factor which can be used for any polarization state of the incident beam.

Trois especes nouvelles de Dixa sont decrites. Trois especes citees sont mentionnees pour la premiere fois des Pyrenees et trois autres pour la premiere fois des Carpates.

Les Wiedemannia accompagnent presque partout les eaux a cours rapide. Leur absence est toujours significative, soit de pollution, soit d'une tres grande pauvrete de la faune dans son ensemble.Sept zones - indiquees par des Wiedemannia de differentes especes - peuvent etre distinguees, de l'amont vers l'aval, dans un meme cours d'eau. En homologuant les territoires d'une meme zone dans des rivieres differentes, la zonation fournie par les Wiedemannia tient compte des temperatures extremes au cours de l'annee et de l'abondance des animaux.Trois sous-especes de W. beckeri et quatre especes sont decrites.

L'auteur fait une revision des Dipteres de la sous-famille des Empididae Hemerodromiinae pour l'Autriche et montre que la plupart des especes figurent dans l'ensemble des Alpes.

Dans une precedente note ont ete etudies les premiers stades d'un Empidide d'Algerie, de la sous-famille des Atalantinae, Roederella ouedorum, dont les larves, rheophiles, detruisent les larves et surtout les nymphes de Simulium sp. Un autre Empidide d'Algerie, de la sous-famille des Hemerodromiinae, Hemerodromia seguyi, dont la larve, la nymphe et l'imago sont decrites ici, a un mode de vie tout a fait analogue; sa larve vit au sein des colonies de larves de Simulies; ces dernieres sont capturees et sucees par la larve predatrice. La nymphe d'Hemerodromia seguyi est nue et fixee sous des pierres immergees, dans des zones de courant faible. In a swift stream of the Aures mountains (Algeria), were collected, on April 1950, a large number of larvae of an Empidid fly of the subfamily Hemerodromiinae: Hemerodromia (Metachela) seguyi n. sp.; they live on immerged rocks, among larvae of Simulium sp., upon which they prey; when feeding, the Empidid larva buries its head in its prey and sucks up the flesh. Pupation takes place usually in crevices of immerged rocks at the water's edge, where the current is slow. The larva and pupa of H. seguyi have been compared respectively to those of Roederella ouedorum, an Empidid fly belonging to the subfamily Atalantinae. The main differences between the larvae are not furnished by the head structure, but by the number of abdominal prolegs, the disposition of hooks on them and the form of the prominence at the end of the body. Pupae of Hemerodromia are easy to distinguish from pupae of other Empidids, for they have eight pairs of long tracheal filaments; other taxonomic characters are the form of the plates of the head on ventral aspect and the disposition of spines on the abdomen.

17 especes de Psychodidae Psychodinae ont ete recoltes par M. A. Thomas dans les Pyrenees. Une espece est nouvelle pour la Science et huit pour la faune pyreneenne.

Les Thaumaleidae sont des Dipteres dont les larves sont etroite­ ment liees a l'habitat hygropetrique (A. THIENEMAN) ou petrimadicole (F. VAILLANT), aussi bien en Eurasie qu'en Afrique et en Amerique. Les imagos ne volent pas longtemps et restent au voisinage des rochers suintants sur les buissons et les arbres. Les differentes especes ne se distinguent que par les caracteres des pieces genitales, aussi bien pour les mâles que pour les femelles.

Quatre especes et une sous-espece nouvelle des Pyrenees sont decrites. Sept autres especes sont signalees pour la premiere fois de cet ensemble montagneux.

The properties of R/sub 2/Fe/sub 14/B-series high-performance permanent magnets are shown to have basic characteristics very sensitive to hydrogen absorption. The cell parameters, Curie temperature, magnetization, anisotropy constants, and coercivity vary nonlinearly with the hydrogen content. Moreover, it is shown how hydrogen absorption can be used as a tool to obtain a better understanding of the possible mechanisms that drive the spin reorientation phenomena. >

Our x-ray photoemission spectroscopy study of ${\mathrm{CeRu}}_{2}$${\mathrm{H}}_{\mathrm{\ensuremath{\approxeq}}4}$ shows the disappearance of a Ce 3d satellite peak which is generally at- tributed to an ${f}^{0}$ final state and a reduction of the ${f}^{2}$-final-state-related intensity. An interpretation in terms of an Anderson model leads to an increase in the f count ${n}_{f}$ from \ensuremath{\approxeq}0.8 to nearly unity and to a change in the 4f\char21{}conduction-band hybridization energy \ensuremath{\Delta} from 120 meV to 60\ifmmode\pm\else\textpm\fi{}20 meV. The observed binding-energy shifts of 0.7 eV (Ce 3d, 5p) and 0.4 eV (Ru 3d) are partly due to the lattice expansion as the 4f bonding contribution disappears. The valence-band spectrum shows weak hydrogen-induced emission at 5\char21{}8 eV. The observation of peaks at \ensuremath{\approxeq}1 eV and \ensuremath{\approxeq}2.6 eV in ${\mathrm{CeRu}}_{2}$ and ${\mathrm{CeRu}}_{2}$${\mathrm{H}}_{\mathrm{\ensuremath{\approxeq}}4}$, respectively, fits well into the ${f}^{1}$-${f}^{0}$ screening scheme.

A theoretical model has been developed for recombination at dangling bonds which explains the γ variations between 0.5 and 1 depending on the Fermi level position. The occupation probabilities of the T3+, T3° and T3- states under illumination have been calculated using the statistics of correlated levels. The γ exponent is derived through a parametric representation of the equations of detailed balance and charge conservation. A good agreement with experiment is obtained with a dangling bond density of 5×1015 cm-3, a placing of the T3° level at 0.95 eV below Ec, an effective correlation energy of 0.4 eV and a charged to neutral capture cross section ratio of 50.

When the authors had seen four cases of ovarian cysts in the newborn during the course of a few months they decided to describe this pathology. All four cases were discovered in utero during the course of ultrasound examination at gestationaL ages between 28 and 36 weeks. Pictures were obtained of round abdominal liquid areas measuring between 45 and 75 mm in diameter, which were separate from the bladder and the kidneys in female fetuses. One of the cysts showed two different ultrasound zones, of which one seemed to be a deposit of blood which was taken to be evidence of torsion of the ovary in utero. The diagnosis was confirmed after birth by clinical examination, straight X-ray of the abdomen, intravenous urography and ultrasound examination of the newborn. The pathological cause of these cysts is still unknown, but suggests that there was probably an abnormal stimulation by the mother's H.C.G. or abnormal enzyme activity of the theca interna. In each case delivery was vaginal. Although in each of these cases the cysts were benign they were treated surgically because all authors agree that there are risks of complications due to torsion or rupture and because one cannot be certain that they are benign.

Seventy cases of myomectomy performed over 5 years (1977 to 1982) in the department of GynecologyObstetrics of the St Antoine Hospital in Paris are analyzed. During the same period, 465 patients underwent hysterectomy for leiomyoma. A brief review shows that myomectomy is not the best surgical treatment of uterine leiomyoma because of its complications. Hemorrhagy, pelvic pain and infertility remain the principle modes of discovery of uterine leiomyoma in operated patients, whose median age is fairly low. Hysterosalpingography is still the main procedure for the investigation and diagnosis of leiomyoma. However, indications of echotomography have been extended with an increase in the frequency of diagnosis of leiomyoma due to a better semiology. Primary leiomyoma section followed by excision appears preferable to conventional enucleation, which is frequently hemorrhagic and blind. In determining the indications of myomectomy, certain factors must be borne in mind: age, parity, type and insertion of leiomyoma, gynecologic history and psychological status. Good postoperative results explain the recent favor of myomectomy as the conservative surgical treatment of leiomyoma; surgical abstention, however, remains the best decision in most cases.

The authors have estimated the maternal plasma volume ine 243 patients by undertaking 282 calculations. The samples were taken often a fairly long time before the delivery, the mean being 4.05 weeks and the maximum being 16 weeks. The results were compared between normal pregnancies and those with hypertension that had no effect on the mother or fetus. The increase in the plasma volume was however significantly far less when the hypertension was severe or when there was intra-uterine growth retardation, either by itself or in association with hypertension. There is a positive correlation between the plasma volume and the fetal weight and thus a good index of normal growth can be worked out. Measuring the plasma volume, therefore, can be used as an early screening technique for severe hypertension with high risk for the fetus.

In Europe, there are only 6 species of the genus Philopotamus Leach, and 4 of them occur in France; one, Ph. corsicanus McL., is endemic of Corsica. The other 3 seem to have different ecological requirements, for their territories overlap very little. Larvae of Ph. ludificatus McL. are extremely abundant in unpolluted torrents of the French Alps and, under almost every big stone over which water flows, several can be found in early spring; they seem to be more numerous in limestone mountains than in igneous ones. I never found a single specimen of Ph. montanus (DONOVAN) in the Alps, but this species is, in the Massif Central, even more abundant than Ph. ludificatus is in the Alps; larvae are found on all kinds of rocks, but are rather rare on limestone; indeed this may be due to low elevation. As for Ph. variegatus McL., it seems to be rather rare everywhere in France, though specimens were collected in different parts of this country.

Structure and magnetic characteristics of RE2Fe14B have been determined on powder and single crystal samples, both by X-ray and neutron diffraction. All the magnetic and structural parameters have been measured versus the absorbed hydrogen. Hydrogen acts indirectly on the magnetic structure via the magnetoelastic couplings, but also directly via the “screenning” effect of hydrogen filling interstices between RE and Fe. Results from various techniques as Mossbauer spectrocopy, μ+SR, magnetization measurements… obtained on pure and hydrided samples are reported.

The cerium intermetallic compounds CeRu 2 and Ce 2 Fe 14 B both readily absorb hydrogen at normal conditions of temperature and pressure. The two systems exhibit fundamental changes in their physical properties corresponding to the transformation from non-magnetic α-type cerium to magnetic γ-type cerium with a localized magnetic moment. Magnetic measurements, neutron diffraction experiments and X-ray photoelectron spectroscopy give evidence of such transitions.

The change in the local structure and electronic configuration in CeFe 2 and CeRu 2 after hydridation have been studied by EXAFS and XANES spectroscopies. Hydridation originate the amorphization of the Ce sublattice and the localization of the 4f electrons in Ce and 3d electrons in iron.