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Several unautomated anti-HEV diagnostic tests are presently available.We have evaluated the performance of the new automated VIDAS® ANTI-HEV IgM and IgG assays.We assessed the reproducibility and cross-reactivity of both VIDAS assays and the analytical sensitivity and linearity of the VIDAS IgG assay. We also tested the VIDAS and comparator assays Wantai IgG and IgM on immunocompetent and immunocompromised patients. Data were analysed according to the infectious profile, with samples from viremic phase (HEV RNA/IgM positive) and post-viremic phase (HEV RNA negative, IgM positive) infections, and uninfected patients (HEV RNA/IgM negative).Within-run reproducibility was10% and between-run reproducibility was12% for both assays. We found no cross-reactivity, except for the VIDAS IgG assay in some patients with HBV (1/10) or malaria (3/23) infections and for the VIDAS IgM assay in some HIV-infected patients (1/10). The VIDAS IgG assay was linear over 0.10-10.0 U/mL. Analytical sensitivity of the IgG assay was 0.71 IU/ml (probit analysis). The clinical sensitivity of the VIDAS IgM assay was 97.65% for viremic samples (83/85) and 59.15% (42/71) for post-viremic samples from immunocompetent patients. It was 78.95% (45/57) for acute phase samples and 77.78% (28/36) for post-viremic samples from immunocompromised patients. Specificity was excellent (99%) in both populations.The analytical and clinical performance of the new VIDAS® ANTI-HEV assays was excellent. These rapid, automated assays for detecting HEV antibodies will strengthen the arsenal for diagnosing HEV infections.

• Effects of two algal polysaccharides, laminarin and carrageenans, on defence responses and signalling in tobacco plants is presented. A possible role as defence elicitors is important in the context of the use of algal extracts as plant protectants. • The effect of the extracts was assessed after infiltration of tobacco leaves, and compared to the effect of a known elicitor of Phytophthora parasitica var. nicotianae(Ppn). • Of the two algal polysaccharides, only carrageenans efficiently induced signalling and defence gene expression in tobacco leaves, as observed with Ppn elicitor. λ-carrageenan, with its high sulphate content, proved the most active. Defence genes encoding sesquiterpene cylase, chitinase and proteinase inhibitor were induced locally, and the signalling pathways mediated by ethylene, jasmonic acid and salicylic acid, were triggered. Some effects lasted for at least a week. • λ-Carrageenan can elicit an array of plant defence responses, possibly through an effect of its high sulphate content. This helps clarify the mechanism of plant protection by algal extracts.

The objective of the present study was to establish the impact of monosex-female redclaw crayfish (Cherax quadricarinatus) culture in gravel-lined ponds, by using a stochastic approach to analyze production dynamics for the 40–60 g, 61–90 g and > 90 g commercial-size intervals. After growing female redclaw crayfish 17 weeks in 2500 m2 gravel-lined ponds stocked at 6 females m− 2, mean final weight was 80.53 ± 0.70 g, survival was 76.2 ± 1.7% and FCR was 0.82 ± 0.10. Overall, yields averaged 0.26 t ha− 1, 2.12 t ha− 1 and 0.99 t ha− 1, respectively, for the 40–60 g, 61–90 g and > 90 g size intervals. This resulted in a mean total biomass of 3.39 t ha− 1 and a commercial biomass of 3.3 t ha− 1. Values of the coefficient of variation of total commercial biomass indicated a maximum certainty in production after 10 weeks, when percentages of recruitment of the 40–60 g and 61–90 g size intervals were similar. The contribution of the > 90 g size interval was negligible, and the total composition of the commercial population was more homogeneous. The sensitivity analysis showed consistency of the simulation model. After 10 weeks, variability of the commercial biomass is particularly influenced by the rate at which mean individual weight (wt.) changes from its initial value to its final value (k). In contrast, after 17 weeks the variability of k was not relevant in determining the variance of commercial biomass, because the influence of k progressively diminishes as the final weight of crayfish is approached. Results from the Monte Carlo simulation indicated that, when increasing sample size from one pond to 100 ponds, variability in production forecasts was reduced 89.8%. The present study demonstrates the feasibility of monosex-female redclaw crayfish culture in gravel-lined ponds. It also shows that the stochastic approach used to analyze production dynamics for the 40–60 g, 61–90 g and > 90 g commercial-size intervals is an important tool to evaluate the impact of size classes on total production and commercial yields. According to our results, we recommend an initial stocking density of 6 organisms m− 2 for commercial monosex grow-out of females in gravel-lined ponds.

This work investigated the structural, biochemical, and molecular characteristics of grape skin cell wall during ripening, related to susceptibility to Botrytis cinerea. The comparative study between the two main grape cultivars in Champagne region, Pinot noir and Chardonnay, quantified: (1) the maturity and physical profile of grape skin, (2) the morphological characteristics, (3) soluble pectic polysaccharides located in grape skin cell walls, and (4) the gene expression of the two main degrading enzymes (VvPME1 and VvPG1) and PME activity. During the maturation period, the grape skins of the two cultivars appear different in their structure and composition. Chardonnay is characterized by higher relative humidity (RH) and level of VvPG1 expression, lower disease incidence and penetrometry values, and thicker cell walls than Pinot noir skins. Thus, the cell wall composition is sufficiently different between grape varieties from the same area to allow their discrimination and could be used to better manage the harvest date.

The nematode Panagrolaimus sp. was tested as live feed to replace Artemia nauplii during first larval stages of whiteleg shrimp Litopenaeus vannamei. In Trial 1, shrimp larvae were fed one of four diets from Zoea 2 to Postlarva 1 (PL1): (A) Artemia nauplii, control treatment; (NC) nematodes enriched in docosahexaenoic acid (DHA) provided by the dinoflagellate Crypthecodinium cohnii; (N) non-enriched nematodes; and (Algae) a mixture of microalgae supplemented in C. cohnii cells. In Trial 2, shrimp were fed (A), (NC) and a different treatment (NS) with nematodes enriched in polyunsaturated fatty acids (PUFAs) provided by the commercial product S.presso®, until Postlarva 6 (PL6). Mysis 1 larvae fed nematodes of the three dietary treatments were 300 μm longer (3.2 ± 0.3 mm) than control larvae. At PL1, control shrimp were 300 μm longer (4.5 ± 0.3 mm) than those fed DHA-enriched or PUFAs-enriched nematodes. No differences were observed in length and survival at PL6 between control larvae and those fed DHA-enriched nematodes (5.1 ± 0.5 mm; 33.1%–44.4%). Shrimp fed microalgae showed a delay in development at PL1. This work is the first demonstration of Panagrolaimus sp. suitability as a complete substitute for Artemia in rearing shrimp from Zoea 2 to PL6.

The aim of this report is to present IBIS (Interactive Brain Imaging System) NeuroNav, a new prototype neuronavigation system that has been developed in our research laboratory over the past decade that uses tracked intraoperative ultrasound to address surgical navigation issues related to brain shift. The unique feature of the system is its ability, when needed, to improve the initial patient-to-preoperative image alignment based on the intraoperative ultrasound data. Parts of IBIS Neuronav source code are now publicly available on-line.Four aspects of the system are characterized in this paper: the ultrasound probe calibration, the temporal calibration, the patient-to-image registration and the MRI-ultrasound registration. In order to characterize its real clinical precision and accuracy, the system was tested in a series of adult brain tumor cases.Three metrics were computed to evaluate the precision and accuracy of the ultrasound calibration. 1) Reproducibility: 1.77 mm and 1.65 mm for the bottom corners of the ultrasound image, 2) point reconstruction precision 0.62-0.90 mm: and 3) point reconstruction accuracy: 0.49-0.74 mm. The temporal calibration error was estimated to be 0.82 ms. The mean fiducial registration error (FRE) of the homologous-point-based patient-to-MRI registration for our clinical data is 4.9 ± 1.1 mm. After the skin landmark-based registration, the mean misalignment between the ultrasound and MR images in the tumor region is 6.1 ± 3.4 mm.The components and functionality of a new prototype system are described and its precision and accuracy evaluated. It was found to have an accuracy similar to other comparable systems in the literature.

Sulfated laminarin (PS3) has been shown previously to be an elicitor of plant defense reactions in tobacco and Arabidopsis and to induce protection against tobacco mosaic virus. Here, we have demonstrated the efficiency of PS3 in protecting a susceptible grapevine cultivar (Vitis vinifera cv. Marselan) against downy mildew (Plasmopara viticola) under glasshouse conditions. This induced resistance was associated with potentiated H2O2 production at the infection sites, upregulation of defense-related genes, callose and phenol depositions, and hypersensitive response-like cell death. Interestingly, similar responses were observed following P. viticola inoculation in a tolerant grapevine hybrid cultivar (Solaris). A pharmacological approach led us to conclude that both callose synthesis and jasmonic acid pathway contribute to PS3-induced resistance.

Juvenile Pacific whiteleg shrimp reared in either outdoor concrete tanks or indoor plastic tanks were exposed to a repeated stress induced by daily handling for 4 weeks. Metabolic responses (glucose, lactate, total protein, cholesterol, triglyceride, total lipid, hemocyanin, and carotenoid content) and immune responses (total hemocyte count, superoxide anion production, and superoxide dismutase activity) were compared with unstressed shrimp. Metabolic responses of stressed shrimp were different in concrete tanks than in plastic tanks. Stressed shrimp from concrete tanks had significantly lower concentrations of total proteins, triglycerides, and total lipids in hemolymph and a significantly lower concentration of carbohydrates in muscle. Stressed shrimp from plastic tanks showed higher concentrations of glucose in hemolymph and higher concentrations of total lipids, but lower concentrations of carbohydrates in the hepatopancreas. Immune responses did not present any significant differences between stressed and unstressed shrimp raised in either experimental system, suggesting that repeated stress does not depress immune response capacity, with the exception of lower levels of total protein in hemolymph. Lower amounts of disturbance occurring in outdoor unstressed shrimp, as well as natural food availability for outdoors tanks could partially explain differences in metabolic responses.

Kinetic study of adenosine concentrations and the expression of adenosine deaminase in mononuclear cells during hemodialysis. Background We previously showed that high intralymphocytic adenosine (Ado) concentrations are found in hemodialyzed patients due to the reduced activity of mononuclear cell adenosine deaminase (MCADA). These abnormalities contribute to the immune defect observed in HD patients. The kinetics of these abnormalities and the causes of the low MCADA activity, however, have not been investigated. Here, we addressed this question. Since interferon gamma (IFNγ) partially modulates MCADA, we also evaluated the effect of IFNγ on MCADA activity in vitro. Methods and Results The study included 12 patients (eight men and four women) who were observed from the first to the 36th hemodialysis (HD) session, and eight healthy subjects (controls). MCADA activity and Ado concentrations were normal before the first HD session. Ado concentrations progressively increased from the first (10.5 ± 3.1 pmol/10 7 cells) to the fourth session (26.7 ± 3 pmol/10 7 cells), before stabilizing at a high level. MCADA activity increased transiently until the second session (2.2 ± 0.5 IU/10 7 cells before HD vs. 2.8 ± 0.6 IU/10 7 cells), and then decreased and stabilized at a low level (1.0 ± 0.5 IU/10 7 cells). The amount of MCADA mRNA transiently increased until the third session (mRNA MCADA/mRNA β-actin: 0.6 ± 0.2 vs. 0.8 ± 0.2), and then decreased to 0.3 ± 0.1 at the 36th session. MCADA activity underwent a dose-dependent increase after IFNγ stimulation. Conclusion HD affects the transcription of the gene encoding MCADA after just three HD sessions, leading to decreased MCADA activity and increased plasma concentration of Ado.

Elicitors are molecules known to trigger plant defence responses against pathogens. In a search for new sources of eliciting compounds from marine algae, an extract was prepared from green algae, Ulva spp., and its elicitor activity was established on the model legume, Medicago truncatula . When infiltrated into plant tissues or sprayed onto the leaves, this extract induced the expression of the defencerelated marker gene PR10 without provoking necrosis. Spraying a solution at 500 m g mL - - 1 was sufficient to obtain maximum induction of PR10 after 2 d. Using a cDNA array enriched in genes potentially involved in plant defence, the expression of 152 genes was monitored after one or two consecutive treatments. A broad range of defence-related transcripts was found to be up-regulated, notably genes involved in the biosynthesis of phytoalexins, pathogenesisrelated proteins and cell wall proteins. In contrast, the expression of primary metabolism-related genes did not change significantly. Consistent with its effect on defence gene expression, it was found that prior treatment of M. truncatula with the Ulva extract protected the plants against subsequent infection by the pathogenic fungus Colletotrichum trifolii .

Pesticides and heavy metals were analyzed in sentinel Crassostrea gigas oysters placed in six aquaculture sites close to a contaminated agricultural region. Each site was sampled twice. Tests revealed the presence of organochlorine (OC) pesticides in the oysters at concentrations varying from 31.8 to 72.5 μg/kg for gamma-hexachlorocyclohexane (γ-HCH); from 1.2 to 3.1 μg/kg for dichlorodiphenyldichloroethylene (4,4-DDE); from 1.6 to 2.3 μg/kg for endosulfan I; and from 1.4 to 41.2 μg/kg for endosulfan II, as well as heavy metals in concentrations that exceeded Mexican tolerance levels (405.5 to 987.8 μg/g for zinc; 4.2 to 7.3 μg/g for cadmium; and 7.2 to 9.9 μg/g for lead). Significant levels of DNA damage in oyster hemocytes were also detected. There was a significant, positive correlation between genotoxic damage and concentration of nickel or the presence of endosulfan II. Cellular viability evaluated by cytotoxic analyses was found to be high at 80%. Marked inhibition in activity of acetylcholinesterase (AChE ) and induction of glutathione S-transferase (GST) activity was noted. Data demonstrated a significant relation between AChE activity inhibition and presence of endosulfan II, γ-HCH, copper, lead, and 4,4-DDE, as well as between AChE and GST activity at different sites.

Background/Aims: In hepatitis C virus-1b, it has been suggested that an amino acid stretch (aa 2209–2248) of the carboxy terminal half of the non-structural 5A (NS5A) region participates in the response to interferon treatment. We tested the hypothesis that absence of mutations in the NS5A (aa 2209–2248) sequence is required for interferon resistance. We also investigated the importance of different HCV-1b isolates in interferon response in France. Methods: We determined the NS5A sequences of 70 patients with chronic hepatitis C before IFN therapy and then compared them with HCV-J prototype sequence. The isolates were determined by NS5B sequencing, the “gold standard” method for genotyping and subtyping. Pre-therapeutic viral load was also measured. Results: No sustained virological response was observed in the patients without amino acid substitutions in the NS5A (aa 2209–2248) sequence, and in the patients with HCV-J isolates. Viral load was significantly higher in the patients with no amino acid substitutions in the NS5A (aa 2209–2248) sequence. Conclusions: In HCV-1b infected patients, an HCV-J strain with no amino acid substitution in the NS5A (aa 2209–2248) region indicates a poor prognosis for response to IFN therapy. The low interferon response rate in HCV-1b infection in Europe is probably not due to a difference between isolates.

Among grapevine trunk diseases, esca proper and apoplexy commonly represent a threat for viticulture worldwide. To retrieve further information about the mechanisms activated in apoplectic and esca proper-affected plants, a two-dimensional gel electrophoresis (2-DE) based analysis was conducted on green stems from 26-year-old standing vines. Symptomatic and asymptomatic stems from both apoplectic (A) and esca proper-affected (E) plants compared to control (without visual symptom since 10 years) stems were studied. Thirty-three differentially expressed proteins were identified by nanoLC-MS/MS and included into three groups conceptually defined as proteins involved in (i) metabolism and energy, (ii) stress tolerance, and (iii) defense response. For nine of them, expression of the relative mRNA's was also monitored by qRT-PCR. Proteome variations were specifically related to apoplexy and esca proper but were more similar in asymptomatic stems than in the symptomatic ones. Remarkable quantitative differences were noted for several proteins in symptomatic stems according to the expressed form, A and E. Results further indicate that similar responses are likely activated in asymptomatic stems but a various quantitative expression is triggered upon onset of apoplexy or esca proper symptoms while both kind of plants are infected by the same pathogenic fungi.

Esca is a destructive disease in grapevines (Vitis vinifera L.) caused by at least three fungi and characterised by two different external symptoms, the apoplectic and leaf stripe form. This latter form can be discerned as soon as symptoms become visible, but the preceding discrete signs during incubation are poorly or not understood. To further understand the development of the leaf stripe form, the period preceding and following the appearance of symptoms was investigated by studying physiological and molecular markers associated with photosynthetic mechanisms and stress response. No perturbation of any targeted metabolism was observed in asymptomatic leaves of asymptomatic canes from vines showing the leaf stripe form of esca. Conversely, drastic alterations of photosynthesis functions were registered in presymptomatic leaves, as revealed by the decrease of gas exchange and chlorophyll fluorescence, and the repression of photosynthesis-related genes. These alterations were amplified during symptom development. Expression of defence-related genes was affected and detected early in presymptomatic leaves and amplified during symptom expression. Our results suggest that grapevines may react precociously by reducing photosynthesis and triggering defence mechanisms in response to the leaf stripe form of esca.

International audience; In grapevine, the penetration and sporulation of Plasmopara viticola occur via stomata, suggesting functional relationships between guard cells and the pathogen. This assumption was supported by our first observation that grapevine (Vitis vinifera cv. Marselan) cuttings infected by P. viticola wilted more rapidly than healthy ones when submitted to water starvation. • Here, complementary approaches measuring stomatal conductance and infrared thermographic and microscopic observations were used to investigate stomatal opening/closure in response to infection. • In infected leaves, stomata remained open in darkness and during water stress, leading to increased transpiration. This deregulation was restricted to the colonized area, was not systemic and occurred before the appearance of symptoms. Cytological observations indicated that stomatal lock-open was not related to mechanical forces resulting from the presence of the pathogen in the substomatal cavity. In contrast to healthy leaves, stomatal closure in excised infected leaves could not be induced by a water deficit or abscisic acid (ABA)treatment. However, ABA induced stomatal closure in epidermal peels from infected leaves, indicating that guard cells remained functional. • These data indicate that the oomycete deregulates guard cell functioning, causing significant water losses. This effect could be attributed to a nonsystemic compound, produced by the oomycete or by the infected plant, which inhibits stomatal closure or induces stomatal opening; or a reduction of the back-pressure exerted by surrounding epidermal cells. Both hypotheses are under investigation.

Brachionus plicatilis are used as live prey for rearing winter flounder larvae at first feeding. This rotifer is grown between 20 and 25 °C (its optimal growth temperature) and then introduced into the 10 °C water in which larvae are reared. The rapid thermal difference between the two media is thought to reduce B. plicatilis quality and consequently affect larval rearing efficiency. In order to optimize larval rearing, a study was conducted to compare the effects of two different diets on larval growth performance and nutritional condition: (1) larvae fed B. plicatilis reared at 24 °C and (2) larvae fed B. plicatilis reared at 24 °C but acclimated overnight at 10 °C. Comparisons were undertaken using morphometric measurements, nucleic acid (RNA/DNA) ratios, total protein content, trypsin activity, and triacylglycerol/sterol ratios. Fatty acid composition of larvae was also studied with a focus on the levels and ratios of three essential fatty acids (docosahexaenoic acid or DHA, eicosapentaenoic acid or EPA, and arachidonic acid or AA). Unique information regarding trypsin activity and lipid components (phospholipid, triacylglycerol, and sterol) of winter flounder larvae is provided in this study. Trypsin activity was detected very early in larvae and was not affected by acclimation of prey. Phospholipid, triacylglycerol, and sterol composition showed no significant difference between the two diets tested and was characterized by high phospholipid content as well as low triacylglycerol and sterol contents. EPA, DHA, AA, DHA/EPA, and DHA/AA decreased from days 12 to 26. Interestingly, DHA content was significantly higher in larvae fed acclimated rotifers and AA content decreased significantly in 26-day-old larvae fed acclimated B. plicatilis . Overall results indicate that overnight acclimation of B. plicatilis at 10 °C is not important for optimizing the rearing of winter flounder larvae although it does influence the fatty acid composition.

The administration of norethindrone, a synthetic progestin, to female rats caused marked decreases in the cholesterol and protein contents of high-density lipoproteins (HDL), A 84% decrease in the total apolipoprotein (apo) E of HDL was associated with a 80% decrease in the proportions of apoE isoforms E1 and E2, whereas E3 and E4 were unchanged. This appears to be the first demonstration of hormonally-induced modification of the apoE phenotype.

Biological activities of estrogen molecules are altered by fluorination of ring A, and the resulting impairment to form catechols. 2-fluoroestradiol (2-F-E2) has been found to be devoid of carcinogenic action despite its high estrogenic potency; its metabolic effects are so far unknown. This study was designed to investigate the effects of 2-F-E2 on lipid metabolism, as compared to those of estradiol-17 beta(E2). Ovariectomized rats received E2 or 2-F-E2 by s.c. injection at a dose of 60 micrograms for three consecutive days. Parameters measured were weights of parametrial fat depots, fat cell volumes, levels of triacylglycerol and acylcholesterol in plasma, and enzymatic responses to the estrogens in isolated parametrial fat cells as evaluated in terms of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) activities. 2-F-E2 and E2 were found to produce comparable decreases in fat depots, cell volumes and plasma levels of acylcholesterol whereas plasma triacylglycerol was unchanged. Both estrogens decreased LPL, and increased HSL activities to the same extent. Thus, 2-F-E and E2 exhibited comparable effects on lipid metabolism. These effects appeared to depend mainly on the estrogenic potency of these molecules, and to be distinct from their carcinogenic action. Despite its high estrogenic potency, 2-F-E2 was found to be slightly less estrogenic than E2.

We investigated concomitantly the effects of ethinyl-estradiol (EE 2 ) at low dose (1.2 μg/animal for 10 days) and high dose (120 μg/animal for 3 days) on body weight, weight of fat stores, triglyceridemia and fat cell lipoprotein lipase and hormone-sensitive lipase activities in female rats. At low dose, EE 2 increased triglyceridemia and lipoprotein lipase activity, whilst high dose decreased both parameters. At low and high doses, and regardless of whether triglyceridemia and lipoprotein lipase activity were increased and decreased, EE 2 caused depletion in fat stores. Fat cells isolated from depleted fat tissue elicited marked increases in the response of hormone-sensitivelipase to epinephrine. Taken together, the data suggest that the potentiation of epinephrine-induced lipolysis in fat cells is likely to represent a major cause to estrogen-induced fat depletion.

The in vivo administration of ethinylestradiol to female rats causes dose-dependent decreases in tri-, di- and monoacylglycerol lipase activities in post-heparin heart effluents; monoacylglycerol lipase is less sensitive to estrogen than the other two.

We investigated the effects of ethinyl estradiol (EE2) on body weight, weights of fat depots, triglyceridemia and lipoprotein lipase (LPL) activity of fat cells isolated from the parametrial fat pads of female rats. LPL activity was assayed at the cell surface, using a suspension of intact fat cells as enzyme source. The cellular uptake of fatty acids liberated during hydrolysis was also evaluated. EE2 was administered daily for 10 days by s.c. injections of 0.06 0.6 6.0 and 60 μg of hormone per animal. EE2 at and above 0.6 jug/rat reduced body weight gain and weights of fat depots. Triglyceridemia increased at doses of EE2 up to 6 μg and showed a relative reduction at 60 μg. In parallel, LPL activity assayed both as cell-bound and heparin-released enzyme and expressed relative to cell DNA, responded to the hormone according to a biphasic pattern: EE2 increased LPL activity in the dose range 0.6-6.0 μg of EE2, whereas a decrease occurred at higher doses. Fat cells incorporated as acylglycerol 56.5 ± 6.2% (mean + SD) of the amount of fatty acid liberated enzymatically during incubation, and this percentage was essentially unchanged by EE2. EE2 at 60 μg/rat caused decreases in triglyceridemia and LPL activity and, as a consequence, decreases in fat depots. By contrast, EE2 at doses up to 6 μg created a paradoxical situation where concomitant increases in triglyceridemia and LPL activity, which should have favoured fat deposition, coexisted with fat depletion. Estrogen hormones at doses below toxicity increase the secretion of triglyceride-rich lipoproteins by liver. Whereas the increase in LPL activity oberved in this study at low doses of EE2 may reflect the LPL responses to liver-borne hypertriglyceridemia, the mechanism for the concomitant fat depletion is unclear. These data emphasize the complex effects of estrogen hormones on lipid metabolism.