Storm-induced transfer of particulate trace metals to the deep-sea in the Gulf of Lion (NW Mediterranean Sea).

In order to calculate budgets of particulate matter and sediment-bound contaminants leaving the continental shelf of the Gulf of Lion (GoL), settling particles were collected in March 2011 during a major storm, using sediment traps. The collecting devices were deployed in the Cap de Creus submarine canyon, which represents the main export route. Particulate matter samples were analyzed to obtain mass fluxes and contents in organic carbon, Al, Cr, Co, Ni, Cu, Zn, Cd, Pb and La, Nd and Sm. The natural or anthropogenic origin of trace metals was assessed using enrichment factors (EFs). Results are that Zn, Cu and Pb appeared to be of anthropogenic origin, whereas Ni, Co and Cr appeared to be strictly natural. The anthropogenic contribution of all elements (except Cd) was refined by acid-leaching (HCl 1 N) techniques, confirming that Zn, Cu and Pb are the elements that are the most enriched. However, although those elements are highly labile (59-77%), they do not reflect severe enrichment (EFs <4). Most particles originate from the Rhone River. This has been confirmed by two different tracing procedures using rare earth elements ratios and concentrations of acid-leaching residual trace metals. Our results hence indicate that even in this western extremity of the GoL, storm events mainly export Rhone-derived particles via the Cap de Creus submarine canyons to the deep-sea environments. This export of material is significant as it represents about a third of the annual PTM input from the Rhone River.

Syngas biomethanation: In a transfer limited process, is CO inhibition an issue?

Syngas biomethanation is a promising technology in the process chain converting wastes to methane. However, gas-liquid mass transfer is a limiting factor of the biomethanation process. To reach high methane productivity, increasing the pressure is an interesting strategy to improve mass transfer. However, the CO content in the syngas raises concerns about a potential inhibition of the microorganisms. Therefore, the aim of the research was to assess the ability to work at high CO partial pressures. In this regard, a pressurized continuous stirred column with a working volume of 10L was implemented and a consortium adapted for syngas-biomethanation for 22 months was submitted to 100% CO and increasing pressure. No inhibition phenomenon was observed for logarithmic PCO as high as 1.8 bar (inlet pressure 5.0 bar), which was the first time that such a high CO partial pressure was tested in continuous mode. Mass transfer limitations allowed for the carboxydotrophic microorganisms to consume CO faster than it was transferred, allowing for the dissolved CO concentration to remain under inhibitory concentrations. These results question the habitual consensus that CO inhibition is a limiting factor of syngas biomethanation.

Syngas biomethanation: Study of process performances at high syngas flow rate in pressurized stirred column.

Syngas biomethanation is a promising technology for waste to energy conversion. However, it had not yet been tested at high syngas flow rates. The aim of this study was to assess the possibility for syngas biomethanation to reach high methane productivity at higher syngas inflow rate. A pressurized stirred column was implemented. The syngas inflow rate was gradually increased, and two different increase strategies were compared. The highest methane productivity achieved yet with syngas-biomethanation was obtained, with 23.2 LCH4/L/d, with high conversion efficiencies of 89% for H2 and 82% for CO. The mass transfer performances of the process were investigated, and the existence of a biological enhancement factor was observed. Considering an enhancement factor in bioprocesses is a pioneering concept that could change the way we design bioreactor to improve mass transfer. The high methane productivity obtained in this study paves the way for the process industrialization.

An optical supernova associated with the X-ray flash XRF 060218.

Long-duration gamma-ray bursts (GRBs) are associated with type Ic supernovae that are more luminous than average and that eject material at very high velocities. Less-luminous supernovae were not hitherto known to be associated with GRBs, and therefore GRB-supernovae were thought to be rare events. Whether X-ray flashes--analogues of GRBs, but with lower luminosities and fewer gamma-rays--can also be associated with supernovae, and whether they are intrinsically 'weak' events or typical GRBs viewed off the axis of the burst, is unclear. Here we report the optical discovery and follow-up observations of the type Ic supernova SN 2006aj associated with X-ray flash XRF 060218. Supernova 2006aj is intrinsically less luminous than the GRB-supernovae, but more luminous than many supernovae not accompanied by a GRB. The ejecta velocities derived from our spectra are intermediate between these two groups, which is consistent with the weakness of both the GRB output and the supernova radio flux. Our data, combined with radio and X-ray observations, suggest that XRF 060218 is an intrinsically weak and soft event, rather than a classical GRB observed off-axis. This extends the GRB-supernova connection to X-ray flashes and fainter supernovae, implying a common origin. Events such as XRF 060218 are probably more numerous than GRB-supernovae.

A restricted cubic spline approach to assess the association between high fat fish intake and red blood cell EPA + DHA content.

BACKGROUND AND AIMS: Fish, especially fatty fish, are the main contributor to eicosapentaenoic (EPA) and docosahexaenoic (DHA) intake. EPA and DHA concentrations in red blood cells (RBC) has been proposed as a cardiovascular risk factor, with <4% and >8% associated with the lowest and greatest protection, respectively. The relationship between high fat fish (HFF) intake and RBC EPA + DHA content has been little investigated on a wide range of fish intake, and may be non-linear. We aimed to study the shape of this relationship among high seafood consumers. METHODS AND RESULTS: Seafood consumption records and blood were collected from 384 French heavy seafood consumers and EPA and DHA were measured in RBC. A multivariate linear regression was performed using restricted cubic splines to consider potential non-linear associations. Thirty-six percent of subjects had an RBC EPA + DHA content lower than 4% and only 5% exceeded 8%. HFF consumption was significantly associated with RBC EPA + DHA content (P [overall association] = 0.021) adjusted for sex, tobacco status, study area, socioeconomic status, age, alcohol, other seafood, meat, and meat product intakes. This relationship was non-linear: for intakes higher than 200 g/wk, EPA + DHA content tended to stagnate. Tobacco status and fish contaminants were negatively associated with RBC EPA + DHA content. CONCLUSION: Because of the saturation for high intakes, and accounting for the concern with exposure to trace element contaminants, intake not exceeding 200 g should be considered.

The French OQALI survey on dairy products: comparison of nutrient contents and other nutrition information on labels among types of brands.

BACKGROUND: Depending on their spending power, consumers may choose foodstuffs from more or less expensive types of brands (national, retailer, economy-line retailer or discount brands). The present study, on dairy products, assesses the nutritional composition and the frequencies of labelled nutrition parameters, according to types of brands. METHODS: The 1646 most consumed dairy products were collected. Nutrient contents and other labelled nutrition parameters provided on the packaging (i.e. nutrition and health claims, nutrition guidelines such as guideline daily amounts, consumption advice and information on added vitamins and minerals) were captured in the French branded product composition database (OQALI). RESULTS: Significant differences between brands were found for energy, protein, fat, saturates, carbohydrate, sugars, dietary fibre, calcium and sodium, in four of six dairy groups studied, but not systematically. National brands and retailer brands provided more detailed nutrition labelling and more frequent nutrition claims than cheaper brands. More retailer brand products provided nutrition guidelines and consumption advice than the other branded products. National brand products more frequently contained added vitamins and minerals and more frequently bore health claims. CONCLUSIONS: Nutrient contents of the cheaper brands of dairy products did not vary systematically from more expensive ones. However, national brands and retailer brands products provided more nutrition information on labels than the cheaper ones. There should be more detailed studies comparing different types of brands regarding labelling practices for nutrient contents and other nutrition information about foodstuffs to help prepare public health recommendations, adapted to all consumers, regardless of their income.

Scriptaid and 5-aza-2'deoxycytidine enhanced expression of pluripotent genes and in vitro developmental competence in interspecies black-footed cat cloned embryos.

Somatic cell nuclear transfer offers the possibility of preserving endangered species including the black-footed cat, which is threatened with extinction. The effectiveness and efficiency of somatic cell nuclear transfer (SCNT) depends on a variety of factors, but 'inappropriate epigenetic reprogramming of the transplanted nucleus is the primary cause of the developmental failure of cloned embryos. Abnormal epigenetic events such as DNA methylation and histone modifications during SCNT perturb the expression of imprinted and pluripotent-related genes that, consequently, may result in foetal and neonatal abnormalities. We have demonstrated that pregnancies can be established after transfer of black-footed cat cloned embryos into domestic cat recipients, but none of the implanted embryos developed to term and the foetal failure has been associated to aberrant reprogramming in cloned embryos. There is growing evidence that modifying the epigenetic pattern of the chromatin template of both donor cells and reconstructed embryos with a combination of inhibitors of histone deacetylases and DNA methyltransferases results in enhanced gene reactivation and improved in vitro and in vivo developmental competence. Epigenetic modifications of the chromatin template of black-footed cat donor cells and reconstructed embryos with epigenetic-modifying compounds enhanced in vitro development, and regulated the expression of pluripotent genes, but these epigenetic modifications did not improve in vivo developmental competence.

Discontinuity induced angular distribution of photon plasmon coupling.

Metal-dielectric transitions are important structures that can display a host of optical characteristics including excitation of plasmons. Metal-dielectric discontinuities can furthermore support plasmon excitation without a severe condition on the incident angle of the exciting photons. Using a semi-infinite thin gold film, we study surface plasmon (SP) excitation and the associated electromagnetic near-field distribution by recording the resulting plasmon interference patterns. In particular, we measure interference periods involving SPs at the scanable metal/air interface and the buried metal/glass one. Supported by optical near-field simulations and experiments, we demonstrate that the metal/glass surface plasmon is observable over a wide range of incident angles encompassing values above and below the critical incident angle. As a result, it is shown that scanning near-field microscopy can provide quantitative evaluation of the real part of the buried surface plasmon wavevector.

Differential contribution of cytoplasmic Ca2+ and Ca2+ influx to gamete fusion and egg activation in maize.

In multicellular organisms, gamete fusion triggers a set of events, collectively known as egg activation, that leads to the development of a new individual. Every species that has been studied shows at least one rise in cytoplasmic Ca2+ concentration ([Ca2+]Cyt) after gamete fusion which is believed to be involved in activation. Yet the source and regulation of this Ca2+ signal and the way it is transduced inside the zygote are controversial. In higher plants, in vitro fertilization (IVF) has enabled the description of a rise in [Ca2+]Cyt (ref. 4) that is sufficient for activation, and of a Ca2+ influx that spreads as a wavefront from the fusion site The relationship between these two responses is unknown. Using a new combination of methods that simultaneously monitor the extracellular flux with a Ca2+-vibrating probe, and [Ca2+]Cyt by widefield imaging, we directly determined that the Ca2+ influx precedes the [Ca2+]Cyt elevation by 40-120 s. In addition, results from experiments using the Ca2+-channel inhibitor gadolinium (Gd3+) suggest that the Ca2+ influx may be necessary for sperm incorporation. We also present evidence for a putative sperm-dependent Gd3+-insensitive localized Ca2+ influx confined to the fusion point.

"Biomethanation of syngas by enriched mixed anaerobic consortium in pressurized agitated column".

In a circular economy approach, heterogeneous wastes can be upgraded to energy in the form of syngas via pyrogasification, and then to methane via biomethanation. Working at high pressure is a promising approach to intensify the process and to reduce gas-liquid transfer limitations. However, raising the pressure could lead to reaching the CO inhibition threshold of the microorganisms involved in syngas-biomethanation. To investigate the impact on pressure on the process, a 10L continuous stirred tank reactor working at 4 bars and 55 °C was implemented. Syngas (40% CO, 40% H2, 20% CO2) biomethanation was performed successfully and methane productivity as high as 6.8 mmolCH4/Lreactor/h with almost full conversion of CO (97%) and H2 (98%) was achieved. CO inhibition was investigated and carboxydotrophs appeared less resistant to high CO exposition than methanogens.

An in vitro system for adhesion and fusion of maize gametes.

The development of in vitro fertilization systems in flowering plants is important for understanding and controlling the mechanisms of fertilization. Here a method is described in which isolated maize gametes fuse. In a medium containing 5 mM calcium chloride, sperm and egg cells adhere for several minutes and then fuse within 10 seconds. The method is specific to male-female gamete pairs and results in 80 percent fusion, whereas fusions with other combinations of gametic and mesophyllic cells are less frequent. Eggs fertilized in vitro do not fuse with additional male gametes, which suggests that a block to polyspermy exists.

Birth of domestic cat kittens of predetermined sex after transfer of embryos produced by in vitro fertilization of oocytes with flow-sorted sperm.

Our goals were to: (1) determine if domestic cat sperm could be sorted to high purity by flow cytometry after overnight shipment of cooled samples; (2) evaluate the efficiency with which sorted sperm could be used to generate cat embryos in vitro; and (3) determine if live kittens of predetermined sex could be produced after transfer of embryos derived by IVF using sorted sperm. Semen samples (n=5) from one male were extended in electrolyte-free solution and shipped overnight at 4 degrees C to the sorting facility. Samples were adjusted to 75x10(6)sperm/mL and stained with Hoechst 33342. After 1h at 34.5 degrees C, samples were adjusted to 50x10(6)sperm/mL with 4% egg yolk TALP+0.002% food dye and sorted by high-speed flow cytometry. Later resort analysis confirmed purities of 94% and 83% for X- and Y-chromosome bearing sperm, respectively. Sorted sperm were centrifuged, re-suspended in TEST yolk buffer and shipped overnight to the IVF laboratory. After IVF of in vivo matured oocytes with X-chromosome bearing sperm, cleavage frequency was 62% (54/87). After IVF of IVM oocytes with control, X- or Y-chromosome bearing sperm, the incidence of cleavage was 42% (48/115), 33% (40/120), and 35% (52/150), respectively, and blastocyst development was 53% (21/40), 50% (11/22), and 55% (23/42), respectively (P>0.05). On Day 2, 45 embryos produced by IVF of in vivo matured oocytes with X-chromosome bearing sperm were transferred to the oviduct of four Day 1 recipients, three of which subsequently delivered litters of one, four, and seven female kittens, respectively. In conclusion, we confirmed that sperm sorting technology can be applied to domestic cats and established that kittens of predetermined sex can be produced.

[Allergic asthma due to sausage mould]. / Asthme allergique à la "fleur de saucisson"

INTRODUCTION: Chronic cough is a common reason for consultation in respiratory medicine. The three most frequent causes of chronic cough are asthma, postnasal drip syndrome or rhinosinusitis, and gastro-oesophageal reflux disease. CASE REPORT: We describe a case of chronic cough related to occupational asthma with sensitivity to dry sausage mould (Penicillium nalgiovensis) in a worker in a semi-industrial pork butchers. The diagnosis was based on the history of symptoms, positive skin prick-tests, spirometry, a normal pulmonary CT-scan, and a favourable outcome after avoidance of the allergen. It was notified as a case of occupational disease. CONCLUSION: A diagnosis of asthma should be considered in a worker exposed to dry sausage mould presenting with respiratory symptoms like chronic cough without evidence of hypersensitivity pneumonitis. Skin prick-tests and allergen avoidance are useful in the diagnosis.

Karyogamy after Electrofusion of Single Egg and Sperm Cell Protoplasts from Maize: Cytological Evidence and Time Course.

In maize, in vitro fusion of isolated male gametes with isolated egg cell protoplasts can be induced by electric pulses. Until now, karyogamy has not been demonstrated. In this study, we cytologically examined fusion products fixed at different times after electrofusion with phase contrast microscopy and transmission electron microscopy. We obtained a precise timetable from 23 samples studied during the first 3 hr. The sperm nucleus was integrated within the egg cell protoplast, migrated toward the egg cell nucleus, and fused with it within 1 hr, as demonstrated by ultrastructural observations, three-dimensional reconstructions of nuclei, and subsequent nuclear volume estimates. Fusion of nuclei occurred before zygotic mitosis, as is the case in vivo. These findings demonstrate karyogamy during in vitro fertilization of maize.

[Medical treatment in peripheral arterial disease: a professional practice study in 262 patients]. / Traitement médical de l'artériopathie oblitérante des membres inférieurs: étude de pratique professionnelle chez 262 patients.

PURPOSE: Antiplatelet agents (APA), statins and angiotensin converting enzyme inhibitors (ACEI) are effective to reduce the risk of cardio-vascular events in patients with peripheral arterial disease (PAD). Few data are available on the actual prescription of these drugs in outpatients and on the effect of hospital care on the level of prescription. METHODS: Retrospective study of patients hospitalized with a confirmed diagnosis of PAD over a one-year period. Comparison of medical treatments on admission and on discharge. RESULTS: 262 patients were included. Mean age was 73 +/- 11 years, and 29% of the patients were women. APA were present in 64% on admission and in 83% when discharged (P < 0.0001). A statin was present in 29% on admission and in 38% when discharged (P = 0.001). ACEI were present in 27% on admission and in 32% when discharged (P= 0.02). A vasodilator was present in 47% on admission and 52% when discharged (P = 0.1). 35% of the patients had isolated PAD. Compared to the patients with associated clinical coronary or cerebro-vascular disease, they were less frequently discharged on statins (respectively 26 and 45%, p = 0.003) and on ACEI (respectively 23 et 38%, P = 0.016) whereas APA were equally prescribed (respectively 82 and 84%, P= 0.7). CONCLUSION: APA were prescribed to a majority of outpatients and the level of prescription was further improved when patients were discharged from the hospital. Statins and ACEI were insufficiently prescribed. On the other hand, vasodilator therapy remained still largely prescribed, despite the lack of any strong effect on morbidity and survival.

Divalent ion-dependent swelling of tomato bushy stunt virus: a multi-approach study.

Time-resolved small-angle X-ray and neutron scattering (SAXS and SANS) in solution were used to study the swelling reaction of TBSV upon chelation of its constituent calcium at mildly basic pH. SAXS intensities comprise contribution from the protein capsid and the RNA moiety, while neutron scattering, recorded in 72% D2O, is essentially due to the protein capsid. Cryo-electron micrographs of compact and swollen virus were used to produce 3D reconstructions of the initial and final conformations of the virus at a resolution of 13 A and 19 A, respectively. While compact particles appear to be very homogeneous in size, solutions of swollen particles exhibit some size heterogeneity. A procedure has been developed to compute the SAXS pattern from the 3D reconstruction for comparison with experimental data. Cryo-electron microscopy thereby provides an invaluable starting (and ending) point for the analysis of the time-resolved swelling process using the scattering data.

Chromosomal aneuploidy in African Wildcat somatic cells and cloned embryos.

In the present study, we compared the incidence of aneuploidy in in vitro fertilized domestic cat embryos (DSH-IVF) with that of African Wildcat (AWC) cloned embryos reconstructed with AWC fibroblast donor cells from different passages (AWC-NT). Fibroblast cells were cultured to passages 1 (P1), 3 (P3), 4 (P4), and 9 (P9), after which cells at each passage were karyotyped and serum-starved before being frozen for nuclear transfer. AWC-NT embryos were produced by fusion of a single AWC somatic cell at P1, P3, P4, or P9 to enucleated domestic cat cytoplast derived from in vitro matured (IVU) oocytes. DSH-IVF embryos were produced after IVU oocytes were fertilized in vitro with domestic cat spermatozoa. To determine chromosome numbers, embryos (2-4-cell) or fibroblast cells were cultured in medium containing 0.28 microg/mL of Colcemid for 22-24 h or 15-24 h, respectively. Subsequently, embryos and cells were placed in hypotonic solution, fixed, and stained for analysis of chromosome spreads by bright field microscopy. Chromosomal abnormalities in AWC fibroblast cells increased progressively during culture in vitro: P1 (43%), P3 (46%), P4 (62%), and P9 (59%). In fibroblast cells, hypoploidy (94/202, 46%) was the major chromosomal abnormality, and it occurred more frequently than hyperploidy (14/202, 7%; p < 0.05). While the percentage of hyperploid cells remained stable during all passages, the proportion of hypoploidy in fibroblast cells increased significantly after P4. The overall incidence of chromosomal abnormalities in AWC-NT embryos at P1 (45%), P3 (60%), and P4 (50%) was similar to that of the fibroblast cells from which they were derived; however, the incidence was higher for embryos reconstructed with donor fibroblasts at P9 (89%). Hypoploidy was the most common chromosomal abnormality observed in either AWC-NT or DSH-IVF embryos. AWCNT embryos reconstructed with donor cells at early passages (P1, P3, and P4) had similar frequencies of chromosomal diploidy, as did DSH-IVF embryos. Accordingly, based on the present results, for NT we are currently using cat donor cells at early passages, when the percentage of cells with chromosomal abnormalities is low. It is recommended that the chromosomal stability of each cell line be analyzed before use as NT donor cells to reduce the incidence of chromosomal anomalies in reconstructed embryos and to possibly produce a subsequent increase in cloning efficiency.

Crystal structure of the Awd nucleotide diphosphate kinase from Drosophila.

BACKGROUND: Nucleotide diphosphate kinase (NDP kinase) is a phosphate transfer enzyme involved in cell regulation and in animal development. Drosophila NDP kinase is the product of the abnormal wing disc (awd) developmental gene, a point mutation in which can produce the killer of prune (K-pn) conditional lethal phenotype. The highly homologous mammalian genes control metastasis and a human NDP kinase acts as a transcription factor. RESULTS: The X-ray structure of the Awd protein prepared from Drosophila was solved at 2.4 A resolution by molecular replacement from the homologous Dictyostelium protein. Both are hexamers, and both have the same fold and the same active site. Subunit contacts differ as a result of sequence changes in the carboxy-terminal segment and in the loop that is the site of the K-pn mutation. CONCLUSIONS: Regulatory properties of animal NDP kinases depend on interactions with other macromolecules, such as DNA and the product of the Drosophila prune gene. The Awd structure suggests an allosteric mechanism of action of NDP kinase where DNA is the effector and the protein undergoes a major conformational change, possibly dissociating to dimers.

The crystal structure of HIV-1 Nef protein bound to the Fyn kinase SH3 domain suggests a role for this complex in altered T cell receptor signaling.

BACKGROUND: Human immunodeficiency virus (HIV) Nef protein accelerates virulent progression of acquired immunodeficiency syndrome (AIDS) by its interaction with specific cellular proteins involved in signal transduction and host cell activation. Nef has been shown to bind specifically to a subset of the Src family of kinases. The structures of free Nef and Nef bound to Src homology region 3 (SH3) domain are important for the elucidation of how the affinity and specificity for the Src kinase family SH3 domains are achieved, and also for the development of potential drugs and vaccines against AIDS. RESULTS: We have determined the crystal structures of the conserved core of HIV-1 Nef protein alone and in complex with the wild-type SH3 domain of the p59fyn protein tyrosine kinase (Fyn), at 3.0 A resolution. Comparison of the bound and unbound Nef structures revealed that a proline-rich motif (Pro-x-x-Pro), which is implicated in SH3 binding, is partially disordered in the absence of the binding partner; this motif only fully adopts a left-handed polyproline type II helix conformation upon complex formation with the Fyn SH3 domain. In addition, the structures show how an arginine residue (Arg77) of Nef interacts with Asp 100 of the so-called RT loop within the Fyn SH3 domain, and triggers a hydrogen-bond rearrangement which allows the loop to adapt to complement the Nef surface. The Arg96 residue of the Fyn SH3 domain is specifically accommodated in the same hydrophobic pocket of Nef as the isoleucine residue of a previously described Fyn SH3 (Arg96-->lle) mutant that binds to Nef with higher affinity than the wild type. CONCLUSIONS: The three-dimensional structures support evidence that the Nef-Fyn complex forms in vivo and may have a crucial role in the T cell perturbating action of Nef by altering T cell receptor signaling. The structures of bound and unbound Nef reveal that the multivalency of SH3 binding may be achieved by a ligand induced flexibility in the RT loop. The structures suggest possible targets for the design of inhibitors which specifically block Nef-SH3 interactions.

Characterization of canine pancreas kallikrein cDNA.

Using a combination of primer extension and RT-PCR, the cDNA encoding a canine tissue kallikrein expressed in the pancreas was cloned and sequenced. The cloned 0.85 kbp cDNA contained a complete open reading frame encoding a polypeptide of 261 amino acids. The calculated molecular mass of the processed, unglycosylated, 237 amino acid protein was 26,428 Da. Its mRNA was expressed at high levels in the pancreas, kidney and submaxillary gland. The sequence of the encoded protein was highly homologous with canine prostatic arginine esterase (66%) and human renal/pancreatic kallikrein (74%). Therefore, the cloned cDNA encoded a previously uncharacterized canine kallikrein enzyme which was named dog renal/pancreatic kallikrein or dK2 according to the new nomenclature for kallikrein gene family members. Because of its specific pattern of tissue expression and the presence of all the amino acid residues necessary for kininogenase activity, we suggest that dK2 is the canine true tissue kallikrein.