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Much of the Antarctic coast is covered by seasonal landfast sea ice (fast ice), which serves as an important habitat for ice algae. Fast‐ice algae provide a key early season food source for pelagic and benthic food webs, and contribute to biogeochemical cycling in Antarctic coastal ecosystems. Summertime fast ice is undergoing a decline, leading to more seasonal fast ice with unknown impacts on interconnected Earth system processes. Our understanding of the spatiotemporal variability of Antarctic fast ice, and its impact on polar ecosystems is currently limited. Evaluating the overall productivity of fast‐ice algae has historically been hampered by limitations in observations and models. By linking new fast‐ice extent maps with a one‐dimensional sea‐ice biogeochemical model, we provide the first estimate of the spatio‐seasonal variability of Antarctic fast‐ice algal gross primary production (GPP) and its annual primary production on a circum‐Antarctic scale. Experiments conducted for the 2005–2006 season provide a mean fast ice‐algal production estimate of 2.8 Tg C/y. This estimate represents about 12% of overall Southern Ocean sea‐ice algae production (estimated in a previous study), with the mean fast‐ice algal production per area being 3.3 times higher than that of pack ice. Our Antarctic fast‐ice GPP estimates are probably underestimated in the Ross Sea and Weddell Sea sectors because the sub‐ice platelet layer habitats and their high biomass are not considered. Antarctic landfast sea ice (fast ice) is sea ice fastened to the coastline of Antarctica and provides a prolific habitat for microalgae. These ice algae are ecologically important because their production takes place early in the season when water column primary production is low. By combining a new satellite data set and a biogeochemical sea‐ice algal growth model, this study provides the first estimate of circum‐Antarctic fast‐ice algal production: 2.8 million tonnes of carbon per year, which is about 12% of the total Antarctic sea‐ice algal production. The mean algal primary production per area in fast ice is 3.3 times higher than that of pack ice. First estimate of circum‐Antarctic landfast sea‐ice annual gross primary production, with a focus on the 2005–2006 seasonMean landfast sea‐ice algal primary production is 2.8 TgC/y, representing 12% (range 5%–19%) of total Southern Ocean ice algal productivityMean modeled landfast sea‐ice algal production per area is 3.3 times higher than that of pack ice First estimate of circum‐Antarctic landfast sea‐ice annual gross primary production, with a focus on the 2005–2006 season Mean landfast sea‐ice algal primary production is 2.8 TgC/y, representing 12% (range 5%–19%) of total Southern Ocean ice algal productivity Mean modeled landfast sea‐ice algal production per area is 3.3 times higher than that of pack ice

Plant epigenetic regulations are involved in transposable element silencing, developmental processes and responses to the environment1–7. They often involve modifications of DNA methylation, particularly through the DEMETER (DME) demethylase family and RNA-dependent DNA methylation (RdDM)8. Root nodules host rhizobia that can fix atmospheric nitrogen for the plant's benefit in nitrogen-poor soils. The development of indeterminate nodules, as in Medicago truncatula, involves successive waves of gene activation9–12, control of which raises interesting questions. Using laser capture microdissection (LCM) coupled to RNA-sequencing (SYMbiMICS data11), we previously identified 4,309 genes (termed NDD) activated in the nodule differentiation and nitrogen fixation zones, 36% of which belong to co-regulated genomic regions dubbed symbiotic islands13. We found MtDMEto be upregulated in the differentiation zone and required for nodule development, and we identified 474 differentially methylated regions hypomethylated in the nodule by analysing ~2% of the genome4. Here, we coupled LCM and whole-genome bisulfite sequencing for a comprehensive view of DNA methylation, integrated with gene expression at the tissue level. Furthermore, using CRISPR–Cas9 mutagenesis of MtDRM2, we showed the importance of RdDM for CHH hypermethylation and nodule development. We thus proposed a model of DNA methylation dynamics during nodule development.

La sinusotomie de type Draf III est une des chirurgies les plus complexes du sinus frontal. Elle permet de limiter les risques de resténose en réunissant les deux ostia et en réséquant le plancher sinusien. Sa réalisation nécessite de bonnes connaissances anatomiques et une expérience chirurgicale certaine pour éviter tout risque de brèche méningée et limiter les risques de resténose. Pour cela, le chirurgien peut s’aider des différents foramens, sillons osseux et artères situés à la partie antérieure de la lame criblée. Le but de cette note technique est d’en expliciter l’utilisation pour la réalisation en toute sécurité de la sinusotomie frontale de type Draf III par voie médiale.

The objectives of the randomized prospective study were to report short-term and long-term outcomes and complications associated with laparoscopic castration in a cohort of dogs; and to validate long-term suppression of testosterone. Two groups were formed: Laparoscopic (LC, n=17) and Conventional (CC, n=7) castration. LC was achieved using a two-port approach and a vessel sealing device to transect testicular blood supply and ductus deferens. For each group, postoperative pain was evaluated. Testosterone concentration was measured at day 1, 6 and 12 months postoperative. Testicular volume was assessed at day 1 and 5 and 6 months postoperative. No major intraoperative complication occurred. Postoperative testosterone concentration was decreased in all dogs and not different from CC group (P=0.09). Testicular volume evolution was marked by an enlargement 5 days postoperatively in 75% of dogs (P=0.007), followed by a significant reduction after 6 months (P=0.007). There was no significant difference in pain scores between both procedures (P=0.24). In conclusion, LC is a reliable technique to achieve testosterone suppression and neutering and deserves further studies including larger cohort and longer follow-up. It cannot be recommended over CC but it is an ideal procedure as adjunctive neutering during another laparoscopic procedure.

We use field observations from late spring and a one‐dimensional sea‐ice model to explore a high nutrient, high chlorophyll system in Antarctic land‐fast ice. Lack of variability in chlorophyll aconcentration and organic carbon content over the 17‐day sampling period suggests a balance between macronutrient sources and biological uptake. Nitrate, nitrite, phosphate, and ammonium were measured at concentrations well above salinity‐predicted levels, indicating nutrient accumulation fueled by remineralization processes. However, silicic acid (DSi) was depleted relative to seawater and was potentially limiting. One‐dimensional physical‐biogeochemical sea‐ice model simulations at the observation site achieve extremely high algal growth and DSi uptake with a DSi half‐saturation constant used for pelagic diatoms (KSi= 3.9 μM) and are not sufficiently improved by tuning the DSi:carbon ratio or DSi remineralization rate. In contrast, diatom biomass in the bottom ice, which makes up 70% of the observed chlorophyll, is simulated using KSian order of magnitude higher (50 μM), a value similar to that measured in a few Antarctic diatom cultures. Some sea‐ice diatoms may therefore experience limitation at relatively high ambient DSi concentrations compared to pelagic diatoms. Our study highlights the urgent need for observational data on sea‐ice algal affinity for DSi to further support this hypothesis. A lower algal growth rate increases model predictions of DSi in the upper sea ice to more accurate concentrations. The model currently does not account for the non‐diatom communities that dominate those layers, and thus, modeling diatom communities overpredicts DSi uptake in the upper ice. Microscopic, single‐celled algae growing inside Antarctic sea ice play a small, but important, role in the carbon cycle of polar oceans. These algae use photosynthesis to convert carbon dioxide to organic carbon and are an important food source for larger organisms. The growth of sea‐ice algae is partly controlled by their uptake of essential nutrients under favorable light conditions. Therefore, a better understanding of nutrients in sea ice can improve ecosystem models. We studied two weeks of measurements of coastal sea‐ice characteristics in late spring at a site in East Antarctica. There were high amounts of both algae and nutrients, indicating recycling processes that return nutrients to the sea ice, even as algae consume nutrients. Sticky biofilms may also prevent nutrients from being removed by seawater. We then tested a sea‐ice model to see if it matched our field measurements. We had to adjust how readily algal cells in the model take up silicon—a nutrient used to build diatoms' (the dominant algal group) walls—from their environment to obtain a close match. Previously used values were taken from experiments with non‐ice associated marine algae, so better estimates specific to sea‐ice algae are needed to accurately include sea‐ice processes in large‐scale models. We observed high chlorophyll aand macronutrient concentrations co‐occurring at the bottom of Antarctic land‐fast sea ice in late springRemineralization processes and adsorption within sea ice best explain the required sources of nitrate and nitrite, phosphate, and ammoniumBiogeochemical modeling suggests that sea‐ice diatoms have a lower affinity for silicic acid than pelagic diatoms

In the Southern Ocean, polynyas exhibit enhanced rates of primary productivity and represent large seasonal sinks for atmospheric CO2. Three contrasting east Antarctic polynyas were visited in late December to early January 2017: the Dalton, Mertz, and Ninnis polynyas. In the Mertz and Ninnis polynyas, phytoplankton biomass (average of 322 and 354 mg chlorophyll a(Chl a)/m2, respectively) and net community production (5.3 and 4.6 mol C/m2, respectively) were approximately 3 times those measured in the Dalton polynya (average of 122 mg Chl a/m2and 1.8 mol C/m2). Phytoplankton communities also differed between the polynyas. Diatoms were thriving in the Mertz and Ninnis polynyas but not in the Dalton polynya, where Phaeocystis antarcticadominated. These strong regional differences were explored using physiological, biological, and physical parameters. The most likely drivers of the observed higher productivity in the Mertz and Ninnis were the relatively shallow inflow of iron‐rich modified Circumpolar Deep Water onto the shelf as well as a very large sea ice meltwater contribution. The productivity contrast between the three polynyas could not be explained by (1) the input of glacial meltwater, (2) the presence of Ice Shelf Water, or (3) stratification of the mixed layer. Our results show that physical drivers regulate the productivity of polynyas, suggesting that the response of biological productivity and carbon export to future change will vary among polynyas. In summer 2016–2017, phytoplankton biomass and NCP in the Mertz and Ninnis polynyas were 3 times those measured in the Dalton polynyaIron‐rich Circumpolar Deep Water and sea ice meltwater best explained this productivity contrast.The productivity contrast between the three polynyas could not be explained by the meteoric water, the Ice Shelf Water, or stratification

La sédentarité est définie par une insuffisance d’activités mobilisatrices régulières dans les activités de la vie quotidienne. L’objectif de ce travail était de rassembler les données concernant le lien potentiel entre sédentarité et incontinence urinaire chez la femme.

Les sujets âgés sont souvent exposés aux médicaments anticholinergiques (ACH) et au risque de syndrome anticholinergique. Il a été retrouvé que cette exposition augmentait leur risque de troubles cognitifs, d’hospitalisation et de mortalité. Cependant, la mesure de la charge anticholinergique n’est pas standardisée dans les études et peu d’entre elles se sont intéressées à la population des sujets âgés en oncologie.

The vertical transport of surface water and carbon into ocean's interior, known as subduction, is one of the main mechanisms through which the ocean influences Earth's climate. New instrumental approaches have shown the occurrence of localized and intermittent subduction episodes associated with small‐scale ocean circulation features. These studies also revealed the importance of such events for the export of organic matter, the so‐called eddy‐pump. However, the transient and localized nature of episodic subduction hindered its large‐scale evaluation to date. In this work, we present an approach to detect subduction events at the scale of the Southern Ocean using measurements collected by biogeochemical autonomous floats (BGCArgo). We show how subduction events can be automatically identified as anomalies of spiciness and Apparent Oxygen Utilization (AOU) below the mixed layer. Using this methodology over more than 4,000 profiles, we detected 40 subduction events unevenly distributed across the Sothern Ocean. Events were more likely found in hot spots of eddy kinetic energy (EKE), downstream major bathymetric features. Moreover, the bio‐optical measurements provided by BGCArgo allowed measuring the amount of Particulate Organic Carbon (POC) being subducted and assessing the contribution of these events to the total downward carbon flux at 100 m (EP100). We estimated that the eddy‐pump represents less than 19% to the EP100 in the Southern Ocean, although we observed particularly strong events able to locally duplicate the EP100. This approach provides a novel perspective on where episodic subduction occurs that will be naturally improved as BGCArgo observations continue to increase. The vertical transport of surface organic carbon into the deep ocean is a fundamental question in oceanography. This transport of carbon supports ocean ecosystems and influences the global climate. Recently, several studies have observed that vertical transport can occur as short‐lived events. These events are the most efficient way to inject surface organic carbon into the ocean, yet they are extremely hard to observe. In this study, we used autonomous floats to capture them. The observations made by these floats during the last 3 years allowed us to map, for the first time, the spatial distribution of vertical transport events throughout the Southern Ocean. Interestingly, we found that these events were concentrated in regions where ocean currents interact with bathymetry. Moreover, our study provides an innovative approach to observe the episodic transport of carbon from autonomous floats. We use Argo floats equipped with biogeochemical sensors to detect subduction events in the Southern OceanWe found that events were concentrated in hot spots of high eddy activity, downstream major topographic featuresOur results suggest that the contribution of this mechanism to the biological carbon pump in the Southern Ocean might be lower than previously proposed

Sea ice is a dynamic biogeochemical reactor and a double interface actively interacting with both the atmosphere and the ocean. However, proper understanding of its annual impact on exchanges, and therefore potentially on the climate, notably suffer from the paucity of autumnal and winter data sets. Here we present the results of physical and biogeochemical investigations on winter Antarctic pack ice in the Weddell Sea (R. V. Polarstern AWECS cruise, June–August 2013) which are compared with those from two similar studies conducted in the area in 1986 and 1992. The winter 2013 was characterized by a warm sea ice cover due to the combined effects of deep snow and frequent warm cyclones events penetrating southward from the open Southern Ocean. These conditions were favorable to high ice permeability and cyclic events of brine movements within the sea ice cover (brine tubes), favoring relatively high chlorophyll‐a (Chl‐a) concentrations. We discuss the timing of this algal activity showing that arguments can be presented in favor of continued activity during the winter due to the specific physical conditions. Large‐scale sea ice model simulations also suggest a context of increasingly deep snow, warm ice, and large brine fractions across the three observational years, despite the fact that the model is forced with a snowfall climatology. This lends support to the claim that more severe Antarctic sea ice conditions, characterized by a longer ice season, thicker, and more concentrated ice are sufficient to increase the snow depth and, somehow counterintuitively, to warm the ice. Winter Weddell Sea pack ice (Antarctica) remains warm and permeable due to large snow depth and frequent occurrence of warm cyclonic eventsThese conditions trigger brine dynamics and associated sea ice biogeochemical processesOf the limited number of winter Weddell Sea pack ice studies (3), this one reveals higher snow depth, negative freeboard, and higher Chl‐a

Sea ice forms a barrier to the exchange of energy, gases, moisture and particles between the ocean and atmosphere around Antarctica. Ice temperature, salinity and the composition of ice crystals determine whether a particular slab of sea ice is habitable for microorganisms and permeable to exchanges between the ocean and atmosphere, allowing, for example, carbon dioxide (CO2) from the atmosphere to be absorbed or outgassed by the ocean. Spring sea ice can have high concentrations of algae and absorb atmospheric CO2. In the summer of 2016–2017 off East Antarctica, we found decayed and porous granular ice layers in the interior of the ice column, which showed high algal pigment concentrations. The maximum chlorophyll aobserved in the interior of the ice column was 67.7 μg/L in a 24% porous granular ice layer between 0.8 and 0.9 m depth in 1.7 m thick ice, compared to an overall mean sea‐ice chlorophyll a(± one standard deviation) of 13.5 ± 21.8 μg/L. We also found extensive surface melting, with instances of snow meltwater apparently percolating through the ice, as well as impermeable superimposed ice layers that had refrozen along with melt ponds on top of the ice. With future warming, the structures we describe here could occur earlier and/or become more persistent, meaning that sea ice would be more often characterized by patchy permeability and interior ice algal accumulations. The growth and melt of Antarctic sea ice is one of the largest seasonal events on Earth. The rapid changes visible at its surface correspond to changes hidden inside the sea ice. East Antarctic sea‐ice samples were collected in 2016–2017 from the icebreaker RSV Aurora Australisto investigate the internal structure of sea ice in summer. Capping the sea ice, impermeable layers inhibited vertical transfer of material through the ice, but ponds had also melted through these layers to allow exchange between the ocean and atmosphere. We also found high concentrations of ice algae deep inside the sea ice, which might be inaccessible to grazers but important for absorbing atmospheric carbon dioxide. With warming temperatures, the observed ice characteristics may become more common or persist longer in each summer with potential consequences for ecosystem processes. East Antarctic summer sea ice can be rotten, with melt ponds, but otherwise sealed by superimposed ice and mostly stratified brineDeep layers of decayed granular crystals allow infiltration of relatively nutrient‐rich seawater and sustain algal assemblagesEvidence for incorporation of old pack ice floes into landfast sea ice East Antarctic summer sea ice can be rotten, with melt ponds, but otherwise sealed by superimposed ice and mostly stratified brine Deep layers of decayed granular crystals allow infiltration of relatively nutrient‐rich seawater and sustain algal assemblages Evidence for incorporation of old pack ice floes into landfast sea ice

Les sujets âgés atteints d’une hémopathie maligne représentent une population à risque chez qui les activités de pharmacie clinique permettraient d’optimiser la prise en charge thérapeutique. Cependant, les ressources humaines disponibles en pharmacie clinique sont souvent limitées ce qui nécessite le développement de solutions permettant d’identifier les patients les plus à risque d’iatrogénie.

L’attitude thérapeutique dans la prise en charge des spondylolisthésis L5-S1 de haut grade reste controversée. La réduction du glissement, la correction de la cyphose lombosacrée ainsi que la nécessité d’un temps antérieur complémentaire sont les points de débat actuels dans la littérature. L’objectif de cette étude est d’exposer les résultats cliniques et radiologiques à long terme d’une technique chirurgicale de réduction et d’arthrodèse instrumentée par un temps postérieur unique.

AimsThe primary aim of this study was to analyse the position of the acetabular and femoral components in total hip arthroplasty undertaken using an anterior surgical approach. Patients and MethodsIn a prospective, single centre study, we used the EOS imaging system to analyse the position of components following THA performed via the anterior approach in 102 patients (103 hips) with a mean age of 64.7 years (sd12.6). Images were taken with patients in the standing position, allowing measurement of both anatomical and functional anteversion of the acetabular component. ResultsThe mean inclination of the acetabular component was 39° (standard deviation (sd)6), the mean anatomical anteversion was 30° (sd10), and the mean functional anteversion was 31° (sd8) five days after surgery. The mean anteversion of the femoral component was 20° (sd11). Anatomical and functional anteversion of the acetabular component differed by >  10° in 23 (22%) cases. Pelvic tilt was the only pre-operative predictive factor of this difference.ConclusionOur study showed that anteversion of the acetabular component following THA using the anterior approach was greater than the recommended target value, and that substantial differences were observed in some patients when measured using two different measurement planes. If these results are confirmed by further studies, and considering that the anterior approach is intended to limit the incidence of dislocation, a new correlation study for each reference plane (anatomical and functional) will be necessary to define a ‘safe zone’ for use with the anterior approach.Take home message: EOS imaging system is helpful in the pre-operative and post-operative radiological analysis of total hip arthroplasty.Cite this article: Bone Joint J2016;98-B:326–333.

Les brèches méningées du sinus frontal sont rares et leur prise en charge chirurgicale difficile. Jusqu’à récemment, elles nécessitaient la réalisation d’un abord chirurgical externe avec volet osseux de table externe. Depuis le développement de la chirurgie endoscopique, des techniques moins invasives telles que des abords endoscopiques exclusifs sont apparues et permettent aujourd’hui des suites opératoires plus simples. Néanmoins, la réalisation de ces techniques requiert une connaissance approfondie de l’anatomie du sinus frontal et de la prise en charge endoscopique des brèches méningées. Cette connaissance est essentielle pour assurer à la fois la fermeture de la brèche et préserver la perméabilité du sinus frontal.

Many articles have shown the usefulness of electrical resistivity tomography (ERT) where characterizing spatial electrical resistivity variations over time associated with water content variations. In a case study of artificial drainage processes in comparison to isolated measurements of the temporal variation in water content, ERT could be used to obtain additional qualitative spatial information (2D or 3D). Indeed, there have been no articles relating the advantages of using ERT to study tile drainage processes. The aim of this article is to explore the effectiveness of the ERT method for delineating soil moisture spatial patterns, following their temporal variations in the context of artificial drainage. First, in the numerical description, taking into account the current knowledge on artificial drainage processes, the authors evaluate the combination of surface and cross‐borehole ERT measurements and different array types. In a field application, the surface and cross‐borehole combination helps to obtain better information on the soil structure and to optimize electrical resistivity monitoring during tile drainage processes. In the second part of the article, the comparison between the ERT data sets and ancillary data from TDR sensors provides a useful critical evaluation of ERT for studying water transfer in waterlogged soil influenced by artificial drainage. The field results showed that ERT contributes additional 2D information on resistivity as related to the water content, which complements single TDR measurements.

Le carcinome rénal tubulokystique est une tumeur rare et généralement de bon pronostic. En revanche, la présence d’une composante peu différenciée, très rare, est grevée d’un mauvais pronostic avec un potentiel d’agressivité et métastatique marqué. Nous présentons le cas d’un patient chez qui le diagnostic de carcinome rénal tubulokystique avec composante peu différenciée a été retenu.

Abstract: Spectral estimation of data sequences with randomly missing samples is considered in this paper. A nonparametric missing-data method is proposed based on interpolation followed by a deconvolution procedure. Sample-and-hold interpolation is considered here. The method is based on the analytic expression of the autocorrelation function of the interpolated data as a linear function of the autocorrelation function of the data to be estimated. Bias and standard deviation of both autocorrelation function and power spectral density are detailed for simulated data based on Monte Carlo analysis. The method is also compared with a fuzzy slotting technique with local normalization and weighting algorithm. Based on the results of these simulations, it is concluded that the performance of the proposed method is better than those of the slotting technique. [Copyright &y& Elsevier]

This paper deals with the development of a new finger articulation prototype used as a joint for anthropomorphic robotic hand. We focus on modeling strategies applied to the finger prototype and its experimental identification. Self-sensing characteristic is achieved by an optimal design of highly back-driveable and efficient electromechanical actuators based on a DC motor, which requires an accurate modeling due to the absence of external sensors. The non-linear model of a finger joint can be reformulated as a Linear Parameter-Varying (LPV) model. On the contrary of classic method used for modeling, a quasi-LPV model is derived from Linear Time Invariant (LTI) interpolation, using a simulated annealing algorithm. Then, our proposed quasi-LPV model is validated from the Inverse Dynamic Model (IDM), and shows a good efficiency in predicting the non-linear behavior of the end effector.

This paper reviews the most significant qualification and reliability achievements obtained, over the last 6 years, by the scientific community for hybrid bonding-based interconnects (HB) also named Cu–Cu or Cu/SiO2bonding. First, the definition of words qualification, robustness and reliability are given to avoid misunderstanding about the published results. Second, the five potential threats (moisture ingress, thermomechanical stresses, electromigration, Cu diffusion, dielectric breakdown) are presented. Finally, the publications of six industrials or Research and Technology Organizations are summarized and discussed. Most of the published data are related to qualification results (pass or fail). Few studies published in-depth studies, mainly on electromigration (Black’s parameters extraction and failure analysis) and copper diffusion (electrical and analytical characterizations). To conclude, once the manufacturing issues (surface preparation, alignment…) have been solved, this technology is robust and reliable at pitches > 1 μm as it reacts, roughly, like a conventional back-end of line (BEoL) interconnect.

Abstract: A haptic system consists of an articulated mechanical structure with motors and position sensors, as well as embedded electronics allowing force feedback. It is driven by a haptic interface, which enables the user to interact with an image in a virtual reality application, through the sense of touch. Thus, it is a hybrid dynamic system, which contains subsystems with continuous dynamics and subsystems with discrete dynamics that interact with each other. This paper develops a hybrid dynamic system model of the system, which takes into account the different sampling periods of the desired regulation, and the interaction between continuous, switching and discrete subsystems. It is interesting when very short electrical transients coexist with very long mechanical ones. [Copyright &y& Elsevier]

A pixel calibration of an IRFPA camera was developed to detect very small temperature variations induced by quasi-static loading of materials. The thermographic data were then used to estimate heat sources accompanying the deformation of PMMA and PC polymers during cyclic tests. The calorimetric balance analysis led us to define several possible ways of introducing the thermoelastic coupling effects in viscothermoelastic models.

The application of statistical simulations to the estimation of transfer free energies of pharmacologically relevant organic molecules is reported. Large-scale molecular dynamics simulations have been carried out on a series of four solutes, viz. antipyrine, caffeine, ganciclovir, and α-d-glucose, at the water−dodecane interface as a model of a biological water−membrane interfacial system. Agreement with experimentally determined partition coefficients is remarkable, demonstrating that free energy calculations, when executed with appropriate protocols, have reached the maturity to predict thermodynamic quantities of interest to the pharmaceutical world. The computational effort that warrants accurate, converged free energies remains, however, in large measure, incompatible with the high-throughput exploration of large sets of pharmacologically active drugs sought by industrial settings. Compared to the cost-effective, fast estimation of simple partition coefficients, the present free energy calculations, nevertheless, offer a far more detailed information about the underlying energetics of the system when the solute is translocated across the water−dodecane interface, which can be valuable in the context of de novo drug design.

In 1982, Guillemin et alreported the isolation of the human (h) growth hormone (GH) releasing factor (GRF) from a pancreatic tumour in an acromegalic patient. Since then, work to develop potent GRF analogues has been widespread and the rat has been the main animal model used. The aim of the present study was to compare the efficacy, potency and specificity of two GRF analogues with those of the native GRF(1–29)NH2using pig (p) as the animal model. Two analogues, Al ([His1, D-Ala2, Ala8,9,15,17, D-Arg29] hGRF(1–29)NH2) and A2 ([D-Ala2, Ala8,9,15,17, D-Arg29] hGRF(1–29)NH2) were compared with the h or pGRF(1–29)NH2. Five studies were designed using 28–48 kg BW growing barrows. Results showed that the two GRF analogues were more potent than the native GRF molecule, were highly specific, were active for long periods of time and were able to induce changes in body composition similar to those reported with GH or other GRF analogues. Because of the similarity between swine and human species with respect to the amino acid sequence of GRF and to the physiology, secretion and effects of GH, it can be proposed that the pig could be used as a pre-clinical animal model to study and test new GRF molecules over short and long periods of time.

A plasmid gap repair assay was used to assess the role of three known nucleases, Exo1, Mre11 and Rad1, in the processing of DNA ends and resolution of recombination intermediates during double-strand gap repair. In this assay, alterations in end processing or branch migration are reflected by the frequency of co-conversion of a chromosomal marker 200 bp from the gap. Gap repair associated with crossing over results in integration at the homologous chromosomal locus, whereas the plasmid remains episomal for non-crossover repair events. In mre11 strains, the frequency of gap repair was reduced 3- to 10-fold and conversion tracts were shorter than in the wild-type strain, consistent with a role for this nuclease in processing double-strand breaks. However, conversion tracts were longer in a strain containing the nuclease deficient allele, mre11-H125N, suggesting increased end processing by redundant nucleases. The frequency of gap repair was reduced 2-fold in rad1 mutants and crossing over was reduced, consistent with a role for Rad1 in cleaving recombination intermediates. The frequency of gap repair was increased in exo1 mutants with a significant increase in crossing over. In exo1 mre11 double mutants gap repair was reduced to below the mre11 single mutant level.

Objective: (1) To assess agreement between laser plethysmography (LPG) and mercury strain-gauge plethysmography (MSGP) measurement of calf volume variation. (2) To assess agreement between LPG and water volumetry measurement of calf volume.Design: Pilot study to evaluate a method of measuring absolute lower leg volume and volume changes in volunteers; randomisation of the leg measured and of the order of measurement, evaluation of between-method correlation and limits of agreement.Setting: Hôpital Civil, Strasbourg.Participants: Seventeen healthy volunteers.Main outcome measures: Measurement of relative volume change by MSGP and LPG before and after venous occlusion by means of a thigh cuff inflated to 20 mmHg (zlV20) and 60 mmHg (/dV60); absolute volume of a 20 cm segment of lower limb measured by differential water plethysmography (two different volume water boots) and by LPG.Results: Comparison of LPG with MSGP led to fairly good correlation coefficients (r = 0.89 and r= 0.91 for δV20 and δV60, respectively) but also to an important dispersion of between-method differences (wide limits of agreement). There was a high degree of agreement between LPG and water volumetry: the correlation coefficient was 0.99 and limits of agreement were [− 6.7% 0.8%] but a significant bias was seen.Conclusions: Laser plethysmography is a new method for measurement of lower limb volume. When tested on inert material, very good accuracy and reproducibility were obtained. Comparison with water volumetry gave good agreement. Evaluation of reproducibility on healthy volunteers is required for complete validation of the device.

We developed a new fluorescent analog of cytosine, the 4-amino-1H-benzo[g]quinazoline-2-one, which constitute a probe sensitive to pH. The 2′-O-Me ribonucleoside derivative of this heterocycle was synthesized and exhibited a fluorescence emission centered at 456 nm, characterized by four major excitation maxima (250, 300, 320 and 370 nm) and a fluorescence quantum yield of Φ = 0.62 at pH 7.1. The fluorescence emission maximum shifted from 456 to 492 nm when pH was decreased from 7.1 to 2.1. The pK_a (4) was close to that of cytosine (4.17). When introduced in triplex forming oligonucleotides this new nucleoside can be used to reveal the protonation state of triplets in triple-stranded structures. Complex formation was detected by a significant quenching of fluorescence emission (∼88%) and the N-3 protonation of the quinazoline ring by a shift of the emission maximum from 485 to 465 nm. Using this probe we unambiguously showed that triplex formation of the pyrimidine motif does not require the protonation of all 4-amino-2-one pyrimidine rings.

AbstractTriple helical structures can be observed between double-stranded nucleic acids and a third strand through the formation of Hoogsteen hydrogen bonds. We report here the synthesis and the preliminary evaluation of oligonucleotides incorporating. 5[(N-2-aminoethyl)-3-aminopropynyl]-2′-deoxyuridine 1as well as its reduced analogue 2.Synthesis of two phosphoramidites 8and 9and the first melting temperature measurements are described.

Abstract The Internet undoubtedly has an important part to play in medical teaching, generally speaking, and particularly in anatomy. We therefore undertook to survey, list, explore and study the various sites written in French or English devoted to anatomy on the Internet in order to evaluate them. Sites were identified from their URL address, by search engine or by hypertext links found in already listed sites. Useless and non-relevant sites were excluded. Fifty-two sites were selected and evaluated as to their navigability, illustrations, text and general presentation. Addresses of theses sites are available on a web page (http://www.rockefeller.univ-lyon1.fr/Anatomie-Lyon-Nord; section liens, section Galerie Virtuelle). This directory could be a very useful working tool for the use of teachers and students. It will be regularly updated.

Natural beta-phosphodiester 16mer and 15mer antisense oligonucleotides targeted against the HIV-1 and HIV-2 TAR RNAs respectively were previously described as sequence-specific inhibitors of in vitro retroviral reverse transcription. In this work, we tested chemically modified oligonucleotide analogues: alpha-phosphodiester, phosphorothioate, methylphosphonate, peptide nucleic acid or PNA, 2'- o -methyl and (N3'-P5') phosphoramidate versions of the 16mer anti-TAR oligonucleotide. PNA, 2'- O -methyl and (N3'-P5') phosphoramidate oligomers showed a strong inhibitory effect compared with the unmodified 16mer, with reverse transcription inhibition (IC50) values in the nanomolar range. The inhibition was sequence-specific, as scrambled and mismatched control oligonucleotides were not able to inhibit cDNA synthesis. No direct binding of the 2'- O -methyl, PNA or (N3'-P5') phosphoramidate anti-TAR oligonucleotides to the HIV-1 reverse transcriptase was observed. The higher T m obtained with 2'- O -methyl, (N3'-P5') phosphoramidate and PNA molecules concerning the annealing with the stem-loop structure of the TAR RNA, in comparison with the beta-phosphodiester oligonucleotides, is correlated with their high inhibitory effect on reverse transcription.

AbstractThe design and the synthesis of a new potential crosslinking agent of DNA is reported. It is based on the alkylating properties of a natural toxin (botryodiplodin) and will be further linked to antisense oligonucleotides.

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Malaria pigment is generated during the growth of the intraerythrocytic parasite plasmodium. This compound is postulated as a product of haemoglobin degradation and consists of an unknown iron porphyrin compound and an apoprotein. We report here a new spectroscopic investigation on the porphyrin component of intact malaria pigment obtained from in vitrocultures of Plasmodium falciparumwithout any previous chemical or biochemical treatment of the sample. We demonstrate the use of resonance Raman microspectrometry, electron paramagnetic resonance spectrometry, and magnetic susceptibility measurements that show the iron porphyrin moiety of the malaria pigment to be a high-spin monomeric iron(III) protoporphyrin hydroxide.

Reaction of H2O2 with ferric leghemoglobin (metLb, the monomeric, oxygen-carrying, heme protein from root nodules of nitrogen-fixing plants) has been previously shown to generate an iron(IV)-oxo (ferryl) species and at least one protein radical. The latter has been suggested to be a tyrosine-derived phenoxyl radical present at Tyr-133 in the soybean protein and Tyr-138 in the lupin protein. To obtain further information on these protein radicals and their potential interaction with the physiologically important peribacteroid membrane (which surrounds the microsymbiont in vivo), EPR spin trapping studies have been carried out with soybean metLb. Evidence has been obtained for at least two additional protein-derived radicals in addition to the phenoxyl radical; these radicals are transient and reactive in nature. These species are carbon-centered, and at least one is a tertiary species (.CR1R2R3); these radicals may be side chain- or alpha-carbon-derived, their exact sites have not been determined. Some of these radicals are on the protein surface and may be key intermediates in the formation of protein dimers. These radicals have been shown to be capable of reacting with peribacteroid membrane fractions, with the consequent generation of lipid-derived radicals. The formation of such radicals may result in the depletion of membrane antioxidants and the initiation of lipid peroxidation. This transfer of damage from the heme center via the protein surface to neighboring membranes may be of considerable biological significance; the destruction of this membrane is one of the earliest observable events in root nodule senescence and is associated with the loss of nitrogen-fixing activity.

BIM-44002, a pure competitive antagonist of parathyroid hormone (PTH), has a high affinity for the PTH/PTHrP receptor in vitro,and can completely inhibit the actions of a PTH agonist in rats in vivo.Toxicology studies in rats and dogs showed BIM-44002 to be devoid of any adverse effects. Therefore we undertook an investigation to evaluate the potential utility of BIM-44002 in lowering elevated serum calcium in three patients with primary hyperparathyroidism. BIM-44002 was administered by continuous intravenous infusion at dosages of 100 μg/hour (370 nmol/hour) for 12 hours, followed by 200 μg/hour for 12 hours, followed by 400 μg/hour for 12 hours. Vital signs and serum ionized and total calcium were monitored hourly and for 3 hours after cessation of the infusion. Blood for PTH determinations was obtained at the same time points. Serum calcium and PTH did not change during and after the infusion of the antagonist. No subject experienced any adverse reactions to the infusion of the antagonist. We conclude that although the PTH antagonist BIM-44002 was effective both in vitroand in vivoin animals, and it was safe in humans, it was not able to lower serum calcium in patients with hyperparathyroidism. Possible reasons for lack of clinical efficacy are discussed.

The enantioselective hydrolysis of epoxyindene and dihydronaphtalene epoxides by the fungus Beauveria sulfurescens(ATCC 7159) is described. This allowed the preparation of both these epoxides, as well as of the corresponding diols, in good to excellent enantiomeric purity.

The biohydrolyses of various substituted styrene oxide derivatives using the fungi Aspergillus nigeror Beauveria sulfurescensare described. The results obtained show that this methodology allows the preparation of enantiomerically enriched epoxides and diols viaenantioselective and regioselective hydration. The comparative study of the results obtained suggests that these hydrolyses operate following different mechanisms and a model of the corresponding active sites is proposed.

Retroviral reverse transcriptase (RT) is involved in the selection of a specific tRNA primer which initiates proviral DNA minus-strand synthesis. Studies of the interactions between human immunodeficiency virus type 1 (HIV-1) RT and primer tRNALys3 have shown that the dihydrouridine (diHU), anticodon, and pseudouridine regions of tRNA are highly protected in the RT-tRNA complex. The CCA 3' end of tRNA is also in close contact with the enzyme during the cDNA initiation step. Using synthetic oligoribonucleotides corresponding to the anticodon and diHU regions, we have previously shown a low but significant inhibition of HIV-1 RT activity. We extend this observation and show that primer tRNA-derived oligodeoxynucleotides (ODNs) carrying a phosphorothioate (PS) modification are strong inhibitors of HIV-1 RT. The affinity of PS-ODNs for the enzyme was monitored by gel mobility shift electrophoresis. Experiments with HIV-1-infected human cells (MT-2 cells) were performed with the latter ODNs. A PS-ODN corresponding to the 3' end of tRNALys3 (acceptor stem [AS]) was able to inhibit HIV-1 replication. No effect of the other modified ODNs was observed in infected cells. The analysis of HIV-1 RNase H activity in a cell-free system strongly suggests that the inhibitory effect of the PS-AS may be mediated via both a sense and an antisense mechanism.

We targeted the mini-exon sequence, present at the 5' end of every mRNA of the protozoan parasite Leishmania amazonensis, by phosphorothioate oligonucleotides. A complementary 16-mer (16PS) was able to kill amastigotes--the intracellular stage of the parasite--in murine macrophages in culture. After 24 hr of incubation with 10 microM 16PS, about 30% infected macrophages were cured. The oligomer 16PS acted through antisense hybridization in a sequence-dependent way; no effect on parasites was observed with noncomplementary phosphorothioate oligonucleotides. The antisense oligonucleotide 16PS was a selective killer of the protozoans without any detrimental effect to the host macrophage. Using 16PS linked to a palmitate chain, which enabled it to complex with low density lipoproteins, improved the leishmanicidal efficiency on intracellular amastigotes, probably due to increased endocytosis. Phosphorothioate oligonucleotides complementary to the intron part of the mini-exon pre-RNA were also effective, suggesting that antisense oligomers could prevent trans-splicing in these parasites.

Gas liquid chromatography, chemical analyses, and infrared and13C-NMR spectroscopies indicated that phycocolloids extracted fromAgardhiella subulata had a dominant ι-carrageenan feature with less deviant ι-carrageenan and υ-carrageenan. The presence of methylated galactose and a small contamination by xylose were registered. Unattached plants were cultivated for 4 weeks in tanks receiving seawater enriched with 53.5 µM nitrate and 0 to 20 µM phosphate (Pi) week−1. The growth was phosphorus (P)-limited up to a tissue P content of 0.14 ± 0.03% dry weight. Maximal specific growth rate and carrageenan content were observed with enrichments of 6 µM Pi and 3 µM Pi, respectively. Hence carrageenan production was promoted in the range of 3–6 µM Pi. Further Pi enrichment was useless. This phenomenon, observed with P nutrition, is comparable to the ‘Neish effect’ in nitrogen nutrition studies.