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Resume Objectif Proposer une actualisation de la prise en charge diagnostique et therapeutique de la recidive biologique apres prostatectomie totale dans le cancer de la prostate. Methodes Une revue systematique (Medline, Pubmed) de la litterature a ete realisee en janvier 2018 a la recherche des elements permettant le diagnostic et le traitement de la recidive biologique apres PT. Resultats La recidive biologique apres prostatectomie se definit par une valeur du PSA ≥ 0,2 ng/mL sur deux dosages successifs a plus de 6 semaines d’une PT. L’IRM (recidive locale) et le tomographie par emission de positron (TEP) sont incontournables dans le diagnostic de la recidive biologique. Le TEP permet de diagnostiquer precocement la recidive locale, ganglionnaire et/ou a distance. La sensibilite de cet examen s’ameliore avec des traceurs plus performants pour des valeurs plus faibles de PSA. Le traitement de la recidive locale repose sur la radiotherapie de rattrapage. L’association radiotherapie–hormonotherapie est preconisee pour les formes a haut risque. Conclusion Cette actualisation de la prise en charge de la recidive biologique apres prostatectomie totale doit permettre d’ameliorer la prise en charge des patients en proposant les examens diagnostiques et le traitement adapte au type de recidive.

The main objective was to report the intra-, post-operative and functional outcomes of living-donor robotic-assisted kidney transplantation (RAKT), performed by a surgeon skilled in robotic surgery. The secondary objective was to compare the results of RAKT, based on the surgeon's experience.For this retrospective cohort study, we analyzed data from consecutive patients who underwent living-donor RAKT from July 2015 to March 2020 and compared the results of RAKT according to the surgeon's experience (group 1: 1-14th RAKT versus group 2: 15-29th RAKT).Twenty-nine living-donor RAKT were performed. The median age and BMI of the recipients were: 57.0 (44.0-66.0) years and 32.7 (23.5-39.6)kg/mLiving-donor robotic-assisted kidney transplantation, performed by a surgeon skilled robotic surgery, ensures good functional results in the medium term.3.

Studies have shown the existence of inter-individual differences in choice behavior, some people seeking for the best (maximizers) and others for a good enough option (satisficers). Here, we explored whether these inter-individual differences are influenced by aging and common personality traits (i.e., Big Five model). Young (n = 125; 19 years old) and elderly adults (n = 101; 86 years old) completed different scales assessing – among others – maximization and Big Five traits. Our results indicated a greater proportion of maximizers in elderly than in young adults. We also found a minor association between maximization and Big Five traits in both groups. In sum, aging influences choice behavior, but this cannot be explained by changes of common personality traits.

The use of foraminifers as bioindicators of pollution in coastal and paralic environments has undergone a very fast development. Among various criteria, morphological abnormalities are sometimes considered as pollution indicators. However, responses to pollutants have not always been distinguished from responses to natural environmental parameters. In particular, endopelic foraminifers often live in changing pH conditions that may induce test deformation. To study pH effects, cultures with pH ranging from normal marine down to ph 7 were prepared using hydrochloric acid to lower the pH. Ammonia beccarii was collected and introduced into these different cultures. Under neutral pH (7.0) conditions, pseudopodial emission was reduced or stopped. Then the test became opaque as a result of superficial alteration, which is the first stage of test decalcification. Decalcification progressively extended over the whole test, first destroying the last chambers, which are thinner. After 15 days, only interlocular walls were preserved, giving the test a star-shape characteristic of an advanced stage of decalcification. If a specimen was maintained in low pH conditions, the test was sometimes entirely destroyed and only the cytoplasm, covered with the Inner Organic Layer, remained. On the other hand, if a specimen with a partially dissolved test was placed in a solution with normal pH, it was able to rebuild its test. Recalcification was somewhat different from the original calcification and was accompanied, in most cases, by morphological abnormalities (e.g., abnormal expansions, irregular chamber sizes, wall with concave form). These observations show that temporary acidification of the environment, causing partial decalcification of the test, is able to induce morphological abnormalities of foraminiferal tests during recalcification. This acidification may be caused by anthropogenic impact or a natural cause. In both cases, deformation of foraminiferal tests yields information on environmental characteristics of the area.

We report on the petrology and chemistry of North West Africa 1068 (NWA 1068), a shergottite recently recovered in Morocco. This meteorite has a total known mass of about 577 g and comprises 23 fragments. The largest fragment is a greenish-brown rock devoid of fusion crust. It displays a porphyritic texture consisting of a fine-grained groundmass and olivine grains. Excluding the impact melt pockets and the minor carbonate veins produced by terrestrial weathering, modal analyses indicate the following mineral proportions: 52 vol% pyroxenes, 22% maskelynite, 21% olivine, 2% phosphates (merrillite and chlorapatite), 2% opaque oxides (mainly ilmenite and chromite) and sulfides, and 1% K-rich mesostasis. Olivines with various habits occur as clusters often associated with chromite, or single crystals ranging in size from 50 mum to 2 millimeters ("megacrysts"). These crystals originate probably from disrupted cumulates with strong affinities with peridotitic shergottites.

North West Africa (NWA) 480 is a new martian meteorite of 28 g found in the Moroccan Sahara in November 2000. It consists mainly of large gray pyroxene crystals (the largest grains are up to 5 mm in length) and plagioclase converted to maskelynite. Excluding the melt pocket areas, modal analyses indicate the following mineral proportions: 72 vol% pyroxenes extensively zoned, 25% maskelynite, 1% phosphates (merrillite and chlorapatite), 1% opaque oxides (ilmenite, ulvospinel and chromite) and sulfides, and 1% others such as silica and fayalite. The compositional trend of NWA 480 pyroxenes is similar to that of Queen Alexandra Range (QUE) 94201 but in NWA 480 the pyroxene cores are more Mg-rich (En(77)-En(65)). Maskelynites display a limited zoning (An(42-50)Ab(54-48)Or(2-4)). Our observations suggest that NWA 480 formed from a melt with a low nuclei density at a slow cooling rate. The texture was achieved via a single-stage cooling where pyroxenes grew continuously. A similar model was previously proposed for QUE 94201 by McSween et al. (1996). NWA 480 is an Al-poor ferroan basaltic rock and resembles Zagami or Shergotty for major elements and compatible trace element abundances. The bulk rock analysis for oxygen isotopes yields Delta(17)O = +0.42parts per thousand, a value in agreement at the high margin, with those measured on other shergottites (Clayton and Mayeda, 1996; Romanek et al., 1998; Franchi et al., 1999). Its CI-normalized rare earth element pattern is similar to those of peridotitic shergottites such as Allan Hills (ALH)A77005, suggesting that these shergottites shared a similar parent liquid, or at least the same mantle source.

North West Africa (NWA 817) is a single stone of 104 g found in the Sahara (Morocco) by meteorite hunters in November 2000. The meteorite is an unbrecciated, medium-grained olivine-bearing clinopyroxenite with a cumulate texture. It consists of zoned euhedral subcalcic augite (Wo(42)En(38-22)F(20-36)), olivine spanning a wide range of compositions (from Fa(56) in the core to Fa(86)) With rare magmatic inclusions and an intercumulus mesostasis made of Fe-bearing albitic plagioclase, Si-rich glass, Ti-magnetite with unusual skeletal growth morphologies containing ilmenite exsolutions, acicular pyroxene, olivine and cristobalite. Trace minerals are sulfide droplets and Cl-apatite. Mineral modes (in vol%) are augite 69%, olivine 10%, mesostasis 20% and Fe-Ti oxides 1%. Pervasive alteration produced a reddish clay mineral (hydrous ferrous silicate) in both olivine crystals and the mesostasis. The major element composition of NWA 817 is very similar to that of the other nakhlites: high FeO, MgO and CaO concentrations reflect the abundance of cumulus augite and olivine. Key element ratios such as FeO/MnO (=37), Na/Al (=0.40), K/La (= 449), Ga/Al (= 3.9 X 10(-4)) and oxygen isotopic composition (Delta(17)O = +0.37parts per thousand) are clear evidence for a Martian origin. The incompatible trace element pattern as in Nakhla displays a strong light rare earth element enrichment relative to chondrite (La-n/Yb-n = 4.89). However, when compared to the other nakhlites, NWA 817 has specific features: (1) a higher modal proportion of mesostasis; (2) quench textures of Ti-magnetite and Fe-rich clinopyroxene; (3) more Mg-rich olivine core compositions whereas the augite core composition is identical for all nakhlites; (4) a stronger Fe enrichment toward crystal rims of these cumulus minerals. The intercumulus minerals (Ti-magnetite with skeletal growth morphology, acicular chains of clinopyroxene and Fe3+-rich feldspar) indicate rapid crystallization in response to a high degree of undercooling at the end of the sample story. (C) 2002 Elsevier Science B.V. All rights reserved.

We have developed a pulsed magnet system with panoramic access for synchrotron x-ray diffraction in magnetic fields up to 31T and at low temperature down to 1.5 K. The apparatus consists of a split-pair magnet, a liquid nitrogen bath to cool the pulsed coil, and a helium cryostat allowing sample temperatures from 1.5 up to 250 K. Using a 1.15MJ mobile generator, magnetic field pulses of 60 ms length were generated in the magnet, with a rise time of 16.5 ms and a repetition rate of 2 pulses/hour at 31 T. The setup was validated for single crystal diffraction on the ESRF beamline ID06.

Multiple myeloma (MM) is a B-cell malignancy characterized by a monoclonal expansion of plasma cells within the bone marrow, the presence of a monoclonal serum immunoglobulin, and the activation of osteoclastic resorption leading to osteolytic lesions. An animal model mimicking human MM consists of grafting 5T2MM cells in the C57BL/KaLwRij mouse. We have inoculated 5T2MM cells intravenously into young recipient mice. The development of the disease was monitored 9 wk later by serum electrophoresis to detect the presence of a paraprotein. Mice were killed 16 wk after inoculation of the 5T2 cells. Osteolytic lesions were analyzed by 3 different methods: numeric radiography using a Faxitron machine, SEM, and X-ray microtomography that provides 3D information and reconstruction. The first 2 methods were used to quantify bonelesions and resorption. We observed the presence of numerous small resorption cavities in the long bones on the endosteal side. The most severe lesions were localized in the metaphy...

At Cape Banza (North Tanganyika Lake), fluids and aragonite chimneys have been collected many times since the discovery of this sublacustrine field in 1987. This sampling has been investigated here for the Sr isotopic compositions and the rare-earth element features of the carbonates and a few fluid samples. The 87Sr/86Sr ratios of the chimneys indicate that they have precipitated from a mixture of lake water (more than 95%) and hydrothermal fluids. No zoning in the chimneys was detected with our Sr data. For the rare-earth elements, the situation is more complex. The external walls of the chimneys are rare-earth-element-poor (La ≈ 500 ppb, Yb ≈ 200 ppb, La/Yb = 2 to 3.4). Their shale normalised rare-earth element patterns suggest that they are in equilibrium with the inferred carbonate-depositing fluids. The rare-earth element concentrations of the internal walls of the chimneys are significantly light rare earth elements (LREE)-enriched with La contents sometimes up to 5 ppm. We suggest that they contain more vent-fluid rare-earth elements than the external wall samples, possibly adsorbed on the surface of growing crystals or simply hosted by impurities. It was not possible to constrain the nature of these phases, but the variations of the compositions of the internal wall materials of the active chimneys with time, as well as data obtained on an inactive chimney indicate that this rare-earth element excess is mobile. Partition coefficients were calculated between the external wall aragonite and carbonate-depositing fluid. The results are strikingly similar to the values obtained by Sholkovitz and Shen (1995) on coral aragonite, and suggest that there is no significant biologic effect on the incorporation of rare-earth elements into coral aragonite and that the various carbonate complexes involved Me(CO3+) complexes are the main LREE carriers in seawater (Cantrell and Byrne, 1987) instead of Me(CO3)2− in Banza fluids) have the same behaviour during aragonite precipitation.

Many juvenile and adult double and multiple tests of benthic foraminifera were observed on specimens grown in laboratory cultures or collected in various natural environments. Our observations bring to light three possible causes for such abnormalities, each one referring to characteristic morphological features. Double tests may result: (1) from an anomaly in the development of a single juvenile, building two or three second chambers or two third chambers, each one possibly developing in an individual whorl; (2) from the early fusion of two juveniles, which both develop after their fusion; (3) from the attachment of a juvenile on a parental test after the schizogony followed by the young's development.

Morphological abnormalities of foraminiferal tests have been studied in cultures of Ammonia tepida and A. beccarii. Regular asexual reproduction cycles of A. tepida show the influence of high salinity on the morphology of juveniles and on the ontogenetic process. A low rate of abnormalities (about 1%) occurs under normal saline conditions (37‰). These are mainly “double tests” or a protuberance on the spiral side, or an abnormal arrangement of the first several chambers. A high rate of abnormalities among the juvenile forms (about 50%) occurs under hypersaline conditions (50‰). These abnormalities include an abnormal shape of the proloculus or of the first several chambers, a modification of the coiling plane of the first several chambers, the development of two whorls from one proloculus, or the fusion of two juveniles. Some adults exposed to hypersaline conditions before the end of their growth have also shown a strong response that is manifested either in abnormal-sized chambers, or in numerous chambers with a complex arrangement. In paralic and coastal environments characterized either by salinity fluctuations or by hypersalinity, morphological abnormalities are similar to those seen in cultures, and can be explain by the same processes. Other phenomena can cause abnormalities in the test. Asexual reproduction can lead to the construction of abnormal chambers on the umbilical side. Decalcification can result in the formation of small additional chambers or new chambers located between two septal walls of the decalcified initial chamber. Regeneration may occur after test damage; this feature is generally recognizable by the scars present on the test. To have utility for various environmental applications we recommend using the term “deformations” to describe abnormalities formed by modification of the test during the life of the foraminifer, and the term “malformations” only to describe abnormalities resulting from an anomaly in the ontogenetic development process. When the origin of the abnormality is not evident, the words “morphological abnormalities” or “abnormal tests” can be used.

Comparison between clasts of the Tatahouine diogenite, collected the day of the fall in 1931 and 63 years later in 1994, allows the evaluation of mineralogical and chemical effects of terrestrial residence on meteorites. Secondary minerals are found in the 1994 samples: iron stains and carbonate rosettes. Major and trace element abundances have been determined on fallen and found clasts. No significant differences have been observed for most elements with the exception of Rb, Sr, and (in a single case) the light rare earth elements (LREE). In this case, the REE pattern of a 1994 clast displays a weak positive Ce anomaly, probably linked to the presence of iron hydroxide. The contents of Rb and Sr are significantly higher in the 1994 samples than in the 1931 clasts and reflect the formation of calcite inside some of the clast fractures. These results demonstrate that weathering processes may change the chemistry of meteorites in a very short time.

The production of several successive generations of megalospheric schizonts, alternating with phases of sexual reproduction, was observed in laboratory cultures of Ammonia tepida . The isolation of megalospheric schizonts facilitated observations on the formation of reproductive cysts and the nearly total decalcification of the parental test during schizogony. These studies also follow the ontogenic development of the test in individuals produced by schizogony. Irregularities during development of the early stages lead to adults with characteristic malformations. This study brings new materials for a better understanding of the trimorphic cycle of Ammonia tepida.

The surface topography of a substratum has been shown to influence the growth and morphology of cells in culture. In this study, human osteoblast-like cells (Saos-2) were cultured on two types of xenogenic biomaterials obtained from bovine bone. Both biomaterials were similar in architectural organization and surface topography, but they differed in matrix components. The first one was characterized by preservation of the mineralized collagen matrix, and the second by complete deproteinization which only preserved the mineral phase. Cells cultured at the surface of both biomaterials were observed using scanning electron microscopy. The β1-integrin subunit, known to bind cell and collagen, is the major integrin of the osteoblast. It was localized using immunogold in transmission electron microscopy. At the surface of the collagen-containing matrix, cells exhibited an elongated shape and oriented axis parallel to the underlying collagen bundles. The β1-integrin subunit was localized at the outer surface of cells, in close association with collagen and at the contact points between cells and biomaterials. In contrast, at the surface of the single mineral matrix, cells were round shaped with random disposition. Gold particles were found around the cells with no specific relation to the biomaterial. These results strongly suggest that the chemical nature of the surface of a bone biomaterial directly influences adhesion process, shape, and spatial organization of cultured osteoblastic cells. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 40, 350–357, 1998.

Polymerization of orthopedic cements makes use of a peroxide initiator which is decomposed by an accelerator to provide free radicals. Free radicals which act on the monomer molecules are also known to induce cell lesions and cell death. We used an in vitro model of cement polymerization to study the effects of free radicals release on osteoblast-like cells. Initiation of methylmethacrylate was done with benzoyl peroxide and acceleration by N,N-dimethylaniline. Bulk polymerization was done in calibrated test tubes which were left aging until use. Polymers (aged from J1 to J31 days after completion of the polymerization process) were sawed to produce slices. Slices were rinsed in distilled water and free radical release was measured by spectrophotometric titration with p-iodonitrotetrazolium. Saos-2 osteoblast-like cells were cultured in parallel on the slices. Cells appeared to be round and were altered when grown on slices prepared freshly after polymerization. Cytomorphometric analysis of the cell shape surface area and form-factor polyethylene confirmed that they spread and flatten on slices prepared a long time after polymerization. Free radical release from polymethylmethacrylate cements is a long-lasting event that can induce bone cells alterations in their neighborhood. Two cytotoxic mechanisms were evidenced: (a) polymer slices released a stable toxic component which could be removed by extensive washing; (b) they released free radicals which were still detectable several days after the end of polymerization. The titration curve was a negative exponential. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 40, 124–131, 1998.

Xenogenic bone biomaterials have been proposed as an alternative to autografts or allografts in human bone restoring or in complement of prosthetic surgery. When appropriate treatments were applied, immunological, inflammatory, bacteriological or virological adverse responses can be prevented. However, these treatments may interact with type I collagen, the major component of the organic bone matrix. Type I collagen can bind osteoblasts via specific cell surface receptors, the integrins. In this work, two different xenogenic biomaterials were studied. Both biomaterials have a bovine bone origin. They displayed similar architectural organization with connected plates and rods and similar surface topography and roughness. They differed by the presence or not of collagen type I. The first one was characterized by preservation of the type I collagen matrix associated with spindle-shaped hydroxyapatite crystals and the second was solely composed by heat-modified apatite crystals. Osteoblast-like cells (Saos-2) were cultured on both biomaterials and examined in scanning and transmission electron microscopy after 7 and 14 days. Both biomaterials were cytocompatible as demonstrated by good ultrastructural cell preservation. (1) At the surface of the collagen containing biomaterial, cells were elongated in shape and oriented according to the trabecular architecture and to the superficial collagen network. After 14 days of culture, cells were confluent and the biomaterial surface was hidden by the cell sheet. The β1 integrin subunit was detected by immunogold in transmission electron microscopy in close relationship with the superficial collagen fibres of the biomaterial and with the outer cell surface. When cultures were carried out in presence of anti β1 integrin subunit, cells were packed and piled up with lack of specific orientation. (2) At the surface of the deproteinized biomaterial, cells were globular without specific disposition and often partially attached to the surface. After 14 days of culture, large areas of the biomaterial surface remained uncovered. Anti β1 subunits conjugated with gold particles were detected around the cells but with no specific association with the deproteinized biomaterial. These results strongly suggest that presence of type I collagen fibres in the matrix of a bone biomaterial is of major interest to determine cell attachment, spreading and orientation via interaction between type I collagen and β1 integrin subunit of osteoblasts.

Nutrition has a strong influence on the immune system of the elderly. Aging induces dysregulation of the immune system, mainly as a result of changes in cell-mediated immunity. Aging is associated with changes to the equilibrium of peripheral T and B lymphocyte subsets, such as decreases in the ratios of mature to immature, naive to memory, T helper 1 subset (TH1) to TH2, and CD5- to CD5+ cells. As a consequence, cell-mediated immune responses are weaker and neither cell-mediated nor humoral responses are as well adapted to the antigen stimulus. Undernutrition, common in aged populations, also induces lower immune responses, particularly in cell-mediated immunity. Protein-energy malnutrition is associated with decreased lymphocyte proliferation, reduced cytokine release, and lower antibody response to vaccines. Micronutrient deficits, namely of zinc, selenium, and vitamin B-6, all of which are prevalent in aged populations, have the same influence on immune responses. Because aging and malnutrition exert cumulative influences on immune responses, many elderly people have poor cell-mediated immune responses and are therefore at a high risk of infection. Nutritional therapy may improve immune responses of elderly patients with protein-energy malnutrition. Supplementation with high pharmacologic doses of a single nutrient (zinc or vitamin E) may be useful for improving immune responses of self-sufficient elderly people living at home. Therefore, nutritional deficiency must be treated in the elderly to reduce infectious risk and possibly slow the aging process.

Wear particles released from hip or knee prostheses are known to be involved in the fibrohistiocytic membrane interposed between bone and implant. During surgical treatment for pelvic carcinoma (5 cases) and for isolated pseudomalignant lymphadenopathy (4 cases) lymph nodes in 9 patients who had had lower limb articular replacement were harvested. Light microscopy and image analysis of the nodes showed florid endosinusal histiocytosis, predominant in the cortical area. Using Oil Red O staining and polarized light, metal particles and polyethylene particles were detected in the large histiocytes. Scanning electron microscopy with electron backscattering allowed us to localize metal particles and perform elemental microanalysis. Iron, cobalt, chromium, nickel, zirconium, and barium, known to be used in prosthetic and cementing materials, were identified as component of these particles. Large amounts of polyethylene particles appeared in all cases while metal particles were found to be abundant in only 2 cases. Thus, migration of polyethylene debris from the prosthetic site seems to be the major factor in development of the histiocytes induced in satellite lymph nodes.

An infrared camera has been used to check the power balance calculations in a series of JET divertor discharges. The discharges spanned the density range (ne)=(1-7)*1019 m-3, with the highest densities achieved by neutral beam heating and intensive gas puffing. For the discharges in which IR data were taken, the total power to the target, as deduced from the IR signal, was proportional to the expected divertor target power estimated from Pin-Prad-W, where Pin is the input power to the plasma, Prad the measured radiated power, and W the rate of change in the plasma stored energy. Close proportionality, pointing to good power balance, has been achieved in ohmic plasmas, as well as in L- and H-modes with either RF and/or NB heating up to 22 MW, of which up to 12 MW was monitored on the target as heat deposition by the IR system. Analysis of the data has shown no systematic trends of deteriorating power balance with increasing volume-averaged density or with heating power.

A new direct HPLC procedure for the simultaneous determination of sulbutiamine (Arcalion) and other thiamine disulfides in human plasma has been developed. The method involves an automated solidphase extraction on octadecylsilyl (C18) cartridges and chromatographic separation of the compounds on an RP Select B column with gradient elution using methanol and phosphate buffer. Detection was by fluorescence of the resulting thiochromes obtained from two on-line post-column reactors. Optimization of post-column reaction parameters has been achieved. This method has been proved to be highly selective for the determination of the thiamine disulfide derivatives and quantitation limits of 5 ng·ml−1 were obtained for each compound in human plasma. Linearity was in the range 5–200 ng·ml−1. Precision and accuracy were also demonstrated by within-day and between-day assays, and showed the good reliability of the method.

An instrument for X-ray emission spectroscopy (XES) based on perfect crystal Bragg optics was recently commissioned at beam line ID26 of the ESRF (European Synchrotron Radiation Facility). The spectrometer is used to record high-energy resolution fluorescence-detected X-ray absorption spectra with sub-lifetime resolution and to perform resonant and non-resonant XES. The hard X-ray probe is material bulk sensitive and allows demanding sample environments (in situ chemistry, high pressure, etc.). Spectrometers for XES are being installed or designed at almost all upcoming synchrotron radiation sources worldwide. The particularity of the ID26 spectrometer is to accommodate five analyser crystals with exact Rowland tracking in the vertical plane and with crystals radii between 0.5 and 2 m.The main upgrade of the new version of this large instrument (3 tonnes, overall size 2.5 m and height 3 m) is to allow the change of the scattering angle over the range 0–180°. This involves rotating the entire spectrometer around a vertical axis that passes through the sample. In order to optimize the vibration stability of the spectrometer's structure, we chose to support the structure in multiple points and not only on three (kinematic mount) like it is specified to do with air pads. According to this choice, we have developed special foot holders for air pads.The calculations during the design phase have shown that we can obtain a first modal frequency of the spectrometer's structure at more than 30 Hz. To confirm our predictive calculations, we have performed some vibration measurements.

An analytical model of the SOL/divertor magnetic geometry is applied to JET. Exponential decay lengths, λ, are related to differences in magnetic fluxes and are expressed in terms of λ at midplane. Consistent values of λ are usually obtained from Langmuir probes in the SOL or in the divertor, and with Lyman-α and Balmer-α profiles in the divertor. Scaling of λ is presented: it is only slightly affected by 〈ne〉, by X-point to target distance and by input power (other than the usual changes Ω⇒L⇒H); it increases strongly with BΦ, especially in H-mode.

The dependence of impurity production and retention on the divertor density, on the power flow into this region as well as on the X-point to target distance are investigated. Model predictions suggest a good impurity retention above a certain divertor (scrape-off) density threshold, which is dependent on heating power. In our experiments pre-programmed midplane or X-point gas puffs were used to scan the density, as well as to avoid the depletion of particles from the divertor and the scrape-off during H-modes. The gas puffs reduce T e and increase N e in particular at the outer strike zone. In general the Be as well as the C influx increases with density, which is understood from the T e ( T i ) dependence of the sputtering yields. The impurity retention shows the expected improvement with increasing scrape-off (divertor) density as well as with increasing X-point to target distance (connection length).

The 1991/92 JET experimental campaign assessed the performance of three different toroidally continuous X-point target plates. The main differences were in the tile material, beryllium and carbon, and the presence of exposed edges. These three configurations have been tested up to power levels in excess of 22 MW and with gas fuelling at the X-point and in the midplane. With the beryllium a radiating divertor was achieved by puffing deuterium into the X-point region, while rapid ELMs resulted from deuterium puffing on the carbon target. The investigation into the importance of small edges, up to 1.5 mm, yielded some interesting results. Although the surface temperature rise was substantially reduced by eliminating exposed tile edges, the onset of the carbon bloom was not delayed by a similar amount. In this paper a model is presented which can explain this and other features of the bloom.

Shigella flexneri causes bacillary dysentery, an invasive disease of colonic epithelial cells in humans. The capacity of bacteria, once they have entered into a cell and escaped the phagocytic vacuole, to spread intracellularly and directly to adjacent cells without further extracellular passage is a key factor in invasion of the epithelial layer. Movement of intracellular bacteria is dependent upon the polymerization of actin; concentration of the formed filaments to one end of the bacterium is associated with initiation of movement. This movement may lead to the formation of a protrusion at the cell surface through which the bacterium passes to an adjacent cell. Development of these protrusions in infected HeLa cells is described, with emphasis on two critical observations. First, initiation of movement is coupled with bacterial division since elongation of the bacterial body is associated with relocalization of the previously uniformly distributed layer of actin to one pole of the bacterium. Second, the actin-bundling protein plastin appears to bundle the actin filaments just posterior to the bacterium, producing an ongoing contraction of the cylindrical actin tail that may be associated with forward movement of the bacterium within the protrusion.

The three-dimensional structure of the axolotl (urodele amphibian) thymus was studied by combined scanning and transmission electron microscopy. The epithelial cell is the major component of the microenvironment forming the meshwork where thymocytes differentiate. Three different types of epithelial cells could be defined by their intracytoplasmic organelles and their localization in the subcapsular or deeper part of the organ. These epithelial cells participate in various types of lymphostromal interactions. Other stromal elements, such as interdigitating reticular cells, macrophages, eosinophil granulocytes and epithelial cysts were also defined. The absence of a true cortico-medullary differentiation in the axolotl thymus, the presence of different stromal elements and the physiological significance of these various microenvironments are discussed.

Cilofungin, a new biosemisynthetic analog of echinocandin B, inhibits the synthesis of beta-(1,3)-glucan resulting in severe modifications of the cell wall and cytoplasmic membrane of sensitive organisms. The morphological modifications to budding yeast cells, pseudomycelium, mycelium and germ tubes of Candida albicans were studied by scanning and transmission electron microscopy after 3 and 16 h exposure to cilofungin. Changes in yeast cell morphology were apparent after 3 h in 0.1 microgram ml-1 cilofungin but were more marked in 1 and 10 micrograms ml-1 cilofungin. Most of the yeasts failed to separate and formed aggregates. Cracks and discontinuities were present in the cell wall and the cell membrane became undulated and fractured. Inclusions into the periplasmalemma space were observed, along with a release of cellular components. An important inhibition of germ tube formation was noted and the structure of true mycelium and pseudomycelium was severely modified. The budding area of yeast cells was particularly susceptible to damage by cilofungin.

A new materials characterization system developed at the XMaS beamline, located at the European Synchrotron Radiation Facility in France, is presented. We show that this new capability allows to measure the atomic structural evolution (crystallography) of piezoelectric materials whilst simultaneously measuring the overall strain characteristics and electrical response to dynamically (ac) applied external stimuli.

The Tatahouine meteorite, in southern Tunisia, shows terrestrial contamination that developed during 63 years of exposure on Earth's surface. Samples collected on the day of the fall in 1931 contained fractures, with no secondary minerals, whereas samples collected in 1994 contain calcite aggregates (70 to 150 micrometers) and rod-shaped forms (100 to 600 nanometers in length and 70 to 80 nanometers in diameter) on the fractures. Carbon isotope analysis of the carbonates within the Tatahouine meteorite [δ 13 C = −2.0 per mil Pee Dee belemnite standard (PDB)] and the underlying ground (δ 13 C = −3.2 per mil PDB) confirm their terrestrial origin.

We provide microscopic evidence that motile rod-shaped forms of Ramlibacter tataouinensis TTB310 are formed from dividing cyst-like cells. Careful estimation of the size of the two morphotypes was conducted using optical and transmission electron microscopy (TEM). The cyst-like cell was shown to be a sphere with a diameter D c = 850 nm . The rod-shaped form was a round-ended cylinder with length L r = 2.91 μm and diameter D r = 239 nm . The membrane area of the two morphotypes was the same. However, the formation of rods from cysts involved loss of two-thirds of the cell volume. TEM showed that, prior to division and transition into rods, cysts contained condensed cytoplasmic material. These results suggest that the morphological transition occurs by pure reshaping of cells.

International audience; Northwest Africa 479 (NWA 479) is a lunar meteorite recovered in 2000 from Morocco. This unbrecciated low-Ti basalt is paired with NWA 032. The texture of NWA 032/479 indicates a simple crystallization history and a fast cooling, followed by an impact event. The occurrence of high-pressure polymorphs of olivine (ringwoodite and wadsleyite) in shock-melt veins indicates shock-pressures of at least 20 GPa. Lithium abundances and isotopic compositions were measured by ion microprobe in pyroxene, olivine crystals, and magmatic inclusions. The δ7Li values in the magmatic inclusions indicate that the NWA 479 parental melt was enriched in 7Li (δ7Li = +15‰). The behavior of Li depicted by the phenocrysts is complex and is not controlled by their major element compositions. Li abundances and δ7Li values range respectively from 3.2 to 11.8 μg/g and +2.4 to +15.1‰ in olivine and from 2.8 to 18.4 μg/g and −0.2 to + 16.1‰ in pyroxene phenocrysts. Neither hot desert weathering, closed-system fractional crystallization, involvement of a low-δ7Li reservoir, degassing of NWA 479 parental melt, nor shock metamorphism correctly explain the Li distribution in the phenocrysts. We propose that the wide range of δ7Li values displayed by the phenocrysts results from the large diffusivity differences between 6Li and 7Li. It is shown that this difference is able to produce large isotopic heterogeneities in a very short time.

(1994). Age‐related changes in the hamster's circadian system partially reversed by treatment with Sulbutiamine, a vit b‐1 related compound. Biological Rhythm Research: Vol. 25, No. 4, pp. 477-479.

A damping system to reduce storage ring quadrupole magnet vibrations, so-called 'damping link', has been implemented at the ESRF. The damping link is a damping device using viscoelastic material (VEM), installed between the girder and the floor. It was used to attenuate the resonant motion of the magnet girder assembly and to improve the electron beam stability and the X-ray beam stability. Vibration tests and finite element analysis were intensively used to identify the resonant motion of the magnet girder assembly, to optimise the design and to check the performance of the damping links. Efforts have been made in the installation of the latter in order to accommodate the environment in the storage ring tunnel. Vibration tests on the magnet girders before and after installation of damping links showed very satisfactory damping performance. Vibrations of the magnet girder assemblies have been effectively attenuated by a factor of about 5.8.

We present a study of the textural signature of terrestrial weathering and related biological activity in the Tatahouine meteorite. Scanning and transmission electron microscopy images obtained on the weathered samples of the Tatahouine meteorite and surrounding soil show two types of bacteria-like forms lying on mineral surfaces: (1) rod-shaped forms (RSF) about 70-80 nm wide and ranging from 100 nm to 600 nm in length; (2) ovoid forms (OVF) with diameters between 70 and 300 nm, They look like single cells surrounded by a cell wall. Only Na, K, C, O and N with traces of P and S are observed in the bulk of these objects. The chemical analyses and electron diffraction patterns confirm that the RSF and OVF cannot be magnetite or other iron oxides, iron hydroxides, silicates or carbonates. The rites of the RSF and OVF are below those commonly observed for bacteria but are very similar to some bacteria-like forms described in the Martian meteorite ALH84001. All the previous observations strongly suggest that they are bacteria or their remnants. This conclusion is further supported by microbiological experiments in which pleomorphic bacteria with morphology similar to the OVF and RSF objects are obtained from biological culture of the soil surrounding the meteorite pieces. The present results show that bacteriomorphs of diameter less' than 100 nm may in fact represent real bacteria or their remnants. (C) 2000 Elsevier Science B.V. All rights reserved.

Foraminifers are increasingly used as bioindicators of environments. Their community structure provides information on the general characteristics of the environment, especially in highly changing paralic environments (e.g., Hayward and Hollis, 1994), and some species are sensitive to specific environmental parameters. Test morphology may also be related to environmental characteristics and is sometimes used as a bioindicator. The size and the density of pores, e.g., have been considered as indicators of dissolved oxygen concentration (Sen Gupta and Machain-Castillo, 1993).

We recently reported that pregnancy affects age-related changes in the distribution of lymphoid and macrophage populations in the spleen of C57Bl/6 mice. In the present study, we examined the influence of pregnancies on the generation of various developmental B-cell subsets and granulocyte/macrophage lineage cells during murine ageing. Using flow cytometry, changes in lymphoid (mature and early B-cell precursors: B220high, B220low, surface immunoglobulin M (sIgM) mu chain +/-) and myeloid (monocyte/macrophage Mac-1/CD11b, granulocyte Gr-1/Ly-6G) compartments were monitored in the bone marrow of young (2 months) and 15- and 23-month-old mice including male, multiparous and virgin female mice. Pregnancies delayed the age-related decline in murine B lymphopoiesis and maintained B-cell reserve capacity during ageing. We also found an increased production of myeloid cells induced by pregnancies at middle (15 months) and advanced (23 months) ages. This comparative study provides new information on changes in marrow lymphopoiesis and myelopoiesis with age. Our data emphasizes that the onset, magnitude and kinetics of age-related changes in the haematopoietic marrow are parity dependent. These changes could influence the incidence of age-related diseases and may account for the greater longevity of females.

The influence of surface roughness and the presence of adhesion molecules in the culture medium were studied regarding cell adhesion, shape, and proliferation of osteoblast-like cells grown on two types of titanium disk. Type I disks were acid etched and type II disks were sandblasted and acid etched. Surface roughness was determined by contact profilometry and scanning electron microscopy. Chemical composition and oxide thickness of the superficial titanium layer were established with energy dispersive X-ray spectrometry, electron spectroscopy for chemical analysis and auger electron spectroscopy. Titanium release in the culture medium was assessed by inductively coupled plasma-optical emission spectrometry. Osteoblast-like cells (Saos-2) were cultured on both types of titanium disks (1) in standard conditions (DMEM culture medium supplemented with fetal calf serum), (FCS), (2) with the culture medium alone (DMEM alone), (3) in the presence of fibronectin or vitronectin (DMEM supplemented with fibronectin or vitronectin). Cultures were also performed in the presence of monoclonal anti-integrin (beta1, alphav) to test the cell adhesion molecules involved in the cell binding to the titanium surface. We found that sandblasting does not modify the chemical surface composition and that titanium represents only 5-6% (in the atom percentage) of surface elements. Release of titanium in the culture medium was found to increase from 24 to 72 hours. In the absence of FCS, fibronectin, or vitronectin, cells appeared scanty and packed in clusters. On the contrary, cells cultured in the presence of FCS, fibronectin, or vitronectin were flattened with large and thin cytoplasmic expansions. The addition of anti beta1 or alphav integrin subunit monoclonal antibody in the culture medium decreased adhesion and spreading of cells, particularly in the presence of fibronectin. Cell proliferation was significantly higher on culture plastic than on both types of disks, but was increased on rough but not on smooth surfaces. These results indicate that a high surface roughness and presence of fibronectin or vitronectin are critical elements for adhesion, spreading, and proliferation of cells on titanium surfaces.

The present study characterized the effects of the novel, selective, and potent 5-hydroxytryptamine1A (serotonin) (5-HT1A) receptor agonist, alnespirone [S-20499, (S)-N-4-[5-methoxychroman-3-yl)propylamino)butyl- 8-azaspiro-(4,5)-diacetamide, hydrochloride] on offensive and defensive resident-intruder aggression in wild-type rats and compared its actions with those of the prototypical full 5-HT1A agonist 8-hydroxy-2- dipropylaminotetralin (8-OH-DPAT), the partial 5-HT1A agonists ipsapirone and buspirone, and the mixed 5-HT1A/1B agonist eltoprazine. All five agonists exerted effective dose-dependent decreases of offensive aggressive behavior in resident rats; 8-OH-DPAT was the most potent (ID50 = 0.074 mg/kg), followed by eltoprazine (0.24), buspirone (0.72), ipsapirone (1.08), and alnespirone (1.24). However, in terms of selectivity of the antiaggressive effects as determined by the absence of decrements in social interest and general motor activity, alnespirone appeared to be superior. In the defensive aggression test, neither alnespirone nor any of the other four agonists changed defensive behaviors in the intruder rats. The involvement of 5-HT1A receptors in the antiaggressive actions of these drugs was confirmed by showing that the selective 5-HT1A receptor antagonist WAY-100635 (N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2- pyridinyl)cyclohexanecarboxamide trihydrochloride), which was inactive alone, fully prevented the antiaggressive effects of alnespirone, 8-OH-DPAT, and buspirone and partly reversed those of ipsapirone and eltoprazine. The data clearly indicate that alnespirone effectively suppresses offensive aggression with an advantageous profile of action compared with other full or partial 5-HT1A agonists. These selective antiaggressive actions of alnespirone are mediated by stimulating 5-HT1A receptors, presumably the somatodendritic autoreceptors at the raphe nuclei. Furthermore, the data provide evidence for a major involvement of these 5-HT1A receptors in the modulation of aggressive behavior by 8-OH-DPAT, ipsapirone, buspirone, and eltoprazine.

Healthy elderly (80±5 years) with different nutritional status were compared to young healthy adults (25±5 years) to quantify the relative influences of aging and nutrition on immune response. Aged persons, without alteration of their nutritional status, had lower CD3+, CD8+, and CD45RA+ as well as higher CD2+CD3−, CD2+CD4−CD8−, and CD45RO+ T cell subsets and IL-6 release than their younger counterparts. T cell proliferation and IL-2 production were comparable in the two healthiest groups. Aged subjects with low nutritional status expressed similar but more marked changes in immune response while nutritional status did not influence the immune response in young subjects. Furthermore, lower nutritional status was associated with lower CD4+ counts and lower T cell functions in aged persons. These results indicate that the influences of aging and undernutrition in humans are cumulative and suggest that some changes in immune response that have been attributed to aging may, in fact, be related to nutrition and not aging.

The surface topography of a substratum has been shown to influence the growth and morphology of cells in culture. In this study, human osteoblast-like cells (Saos-2) were cultured on two types of xenogenic biomaterials obtained from bovine bone. Both biomaterials were similar in architectural organization and surface topography, but they differed in matrix components. The first one was characterized by preservation of the mineralized collagen matrix, and the second by complete deproteinization which only preserved the mineral phase. Cells cultured at the surface of both biomaterials were observed using scanning electron microscopy. The beta 1-integrin subunit, known to bind cell and collagen, is the major integrin of the osteoblast. It was localized using immunogold in transmission electron microscopy. At the surface of the collagen-containing matrix, cells exhibited an elongated shape and oriented axis parallel to the underlying collagen bundles. The beta 1-integrin subunit was localized at the outer surface of cells, in close association with collagen and at the contact points between cells and biomaterials. In contrast, at the surface of the single mineral matrix, cells were round shaped with random disposition. Gold particles were found around the cells with no specific relation to the biomaterial. These results strongly suggest that the chemical nature of the surface of a bone biomaterial directly influences adhesion process, shape, and spatial organization of cultured osteoblastic cells.

Xenogenic bone biomaterials have been proposed as an alternative to autografts or allografts in human bone restoring or in complement of prosthetic surgery. When appropriate treatments were applied, immunological, inflammatory, bacteriological or virological adverse responses can be prevented. However, these treatments may interact with type I collagen, the major component of the organic bone matrix. Type I collagen can bind osteoblasts via specific cell surface receptors, the integrins. In this work, two different xenogenic biomaterials were studied. Both biomaterials have a bovine bone origin. They displayed similar architectural organization with connected plates and rods and similar surface topography and roughness. They differed by the presence or not of collagen type I. The first one was characterized by preservation of the type I collagen matrix associated with spindle-shaped hydroxypatite crystals and the second was solely composed by heat-modified apatite crystals. Osteoblast-like cells (Saos-2) were cultured on both biomaterials and examined in scanning and transmission electron microscopy after 7 and 14 days. Both biomaterials were cytocompatible as demonstrated by good ultrastructural cell preservation. (1) At the surface of the collagen containing biomaterial, cells were elongated in shape and oriented according to the trabecular architecture and to the superficial collagen network. After 14 days of culture, cells were confluent and the biomaterial surface was hidden by the cell sheet. The beta 1 integrin subunit was detected by immunogold in transmission electron microscopy in close relationship with the superficial collagen fibres of the biomaterial and with the outer cell surface. When cultures were carried out in presence of anti beta 1 integrin subunit, cells were packed and piled up with lack of specific orientation. (2) At the surface of the deproteinized biomaterial, cells were globular without specific disposition and often partially attached to the surface. After 14 days of culture, large areas of the biomaterial surface remained uncovered. Anti beta 1 subunits conjugated with gold particles were detected around the cells but with no specific association with the deproteinized biomaterial. These results strongly suggest that presence of type I collagen fibres in the matrix of a bone biomaterial is of major interest to determine cell attachment, spreading and orientation via interaction between type I collagen and beta 1 integrin subunit of osteoblasts.

Polymerization of orthopedic cements makes use of a peroxide initiator which is decomposed by an accelerator to provide free radicals. Free radicals which act on the monomer molecules are also known to induce cell lesions and cell death. We used an in vitro model of cement polymerization to study the effects of free radicals release on osteoblast-like cells. Initiation of methylmethacrylate was done with benzoyl peroxide and acceleration by N,N-dimethylaniline. Bulk polymerization was done in calibrated test tubes which were left aging until use. Polymers (aged from J1 to J31 days after completion of the polymerization process) were sawed to produce slices. Slices were rinsed in distilled water and free radical release was measured by spectrophotometric titration with p-iodonitrotetrazolium. Saos-2 osteoblast-like cells were cultured in parallel on the slices. Cells appeared to be round and were altered when grown on slices prepared freshly after polymerization. Cytomorphometric analysis of the cell shape (surface area and form-factor polyethylene confirmed that they spread and flatten on slices prepared a long time after polymerization. Free radical release from polymethylmethacrylate cements is a long-lasting event that can induce bone cells alterations in their neighborhood. Two cytotoxic mechanisms were evidenced: (a) polymer slices released a stable toxic component which could be removed by extensive washing; (b) they released free radicals which were still detectable several days after the end of polymerization. The titration curve was a negative exponential.

The proportion of aged individuals has rapidly increased in the second half of the twentieth century in both Westem and developing countries. One of the major consequences of this growing elderly population is the significant increase in health care expenses. For example, although persons over the age of 60 years represent only 17% of the French population, nearly half of the nation’s health care resources are dedicated to them, due to their increased susceptibility to infection and other diseases. This increase in the population of elderly people will continue for at least thirty more years (until 2025); health care expenses will also rise accordingly. Consequently, the health care systems of many countries are undergoing drastic revisions. Growing scientific and popular interest in aging process has led to increased finding for aging research, which focuses not only on age-related pathologies but also on research on the normal aging process. The aging process is influenced by several factors, of which genetic background, exposure to environmental factors such as nutritional habits, and exposure to antigens are the most important. Nutrition, in particular, has been recognized to influence age-related diseases (Lesourd 1990a, Feldman 1993), such as the relationship between lipid consumption and cardiovascular disease (Wei 1992) and the prevention of age-related bone fractures (Lesourd et al. 1992a). Both of these examples figure prominently in the increased spending on health care. Furthermore, the increased mortality associated with infection during periods of famine provides additional evidence of the influence of nutrition and nutritional status on defense mechanisms (Chandra 1992a). Despite increased health care expenditures, infection remains the fourth leading cause of death in the elderly (Chandra 1989). In particular, the elderly are more susceptible to viral infection than their younger counterparts, with lung infections in hospitalized elderly patients representing the most monoclonal prevalent infection. Furthermore, influenza is one of the main causes of mortality in elderly people (Sprenger et al. 1991, McBean et al. 1993), especially those who are undernourished and, therefore, unable to increase their antibody levels after influenza vaccination (Chandra et al. 1984a, Lesourd 1990b). In addition, undernutrition has been identified as a major contributing factor to morbidity and mortality in hospitalized aged patients (Sullivan et al. 1990, Sullivan and Walls 1995a), in recovering aged patients after hospital exit (Sullivan and Walls 1995b), as well as in free-living, apparently healthy elderly (Klonoff-Cohen et al. 1992, Corti et al. 1994). Undernutrition increases the risk of infection in the elderly, which is directly proportional to the degree of undernutrition (Sullivan and Walls 1995a). With recent developments in understanding the finction and regulation of the immune system in the last thirty years, the relationship between nutrition and immunology has become better understood (Scrimshaw et al. 1988, Chandra 1988, Bendich 1990, Chandra 1992qFeldman 1993, Chandra and Kumari 1994, Meydani et al. 1995). Although both nutrition and immunology play an important role in the aging process, it has only been recently that the influence of nutrition on the aging immune system has been investigated (Moulias et al. 1985a, Meydani et al. 1986, Chandra 1989, Lesourd 1990a, Lesourd 1990b, Chandra 1992a). The purpose of this review is to focus on the interrelation of immunity and nutrition in old age, concentrating on five key questions: (1) What are the main features of the aging immune response-is it characterized by a global decrease in immune response (Makinodan and Kay 1980) or a dysregulation of the immune system (Weksler 1995)? (2) What is the importance of undernutrition in aged individuals? (3) What is the importance of age-related nutritional deficiency on the immune response of aged individuals (Lesourd 1990a, Lesourd 1990b)? and (4) Are nutritional interventions usefil in preventing or modifying age-related changes in the immune system? And if so, ( 5 ) Are they of any clinical relevance? We focus essentially on “healthy” elderly, a very rapidly growing population in Western countries, for whom good health maintenance not only permits a high quality of life after retirement (a growing concern of people aged 60-80 years) but