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Sample records for stage l1 larvae

  1. Caenorhabditis elegans battling starvation stress: low levels of ethanol prolong lifespan in L1 larvae.

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    Paola V Castro

    Full Text Available The nematode Caenorhabditis elegans arrests development at the first larval stage if food is not present upon hatching. Larvae in this stage provide an excellent model for studying stress responses during development. We found that supplementing starved larvae with ethanol markedly extends their lifespan within this L1 diapause. The effects of ethanol-induced lifespan extension can be observed when the ethanol is added to the medium at any time between 0 and 10 days after hatching. The lowest ethanol concentration that extended lifespan was 1 mM (0.005%; higher concentrations to 68 mM (0.4% did not result in increased survival. In spite of their extended survival, larvae did not progress to the L2 stage. Supplementing starved cultures with n-propanol and n-butanol also extended lifespan, but methanol and isopropanol had no measurable effect. Mass spectrometry analysis of nematode fatty acids and amino acids revealed that L1 larvae can incorporate atoms from ethanol into both types of molecules. Based on these data, we suggest that ethanol supplementation may extend the lifespan of L1 larvae by either serving as a carbon and energy source and/or by inducing a stress response.

  2. Possible presence of common tyvelose-containing glycans in Trichinella L1 larvae and embryonated eggs of several nematodes

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    Dea-Ayuela M.A.

    2001-06-01

    Full Text Available A monoclonal antibody (mAb US4 recognising an epitope containing tyvelose within the T. spiralis L-1 muscle larvae (TSL-1 antigens was tested in western-blot against various antigenic preparations from different stages of the following nematodes: T. spiralis (L1,adult, T. muris (egg, L1, L3, adult, Ascaris suum (egg, adult, Toxocara canis (egg, adult, Anisakis simplex (L3 and Haemochus contortus (egg. Positive reaction was present in antigen preparations from L1 larvae of T. spiralis and T. muris and from embryonated eggs of T. muris, A. suum, T. canis and H. conlortus.

  3. Stage-dependent toxicity of bisphenol a on Rhinella arenarum (anura, bufonidae) embryos and larvae.

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    Wolkowicz, Ianina R Hutler; Herkovits, Jorge; Pérez Coll, Cristina S

    2014-02-01

    The acute and chronic toxicity of bisphenol A (BPA) was evaluated on the common South American toad Rhinella arenarum embryos and larvae by means of continuous and pulse exposure treatments. Embryos were treated continuously from early blastula (S.4) up to complete operculum (S.25), during early larval stages and by means of 24 h pulse exposures of BPA in concentrations ranging between 1.25 and 40 mg L(-1) , in order to evaluate the susceptibility to this compound in different developmental stages. For lethal effects, S.25 was the most sensitive and gastrula was the most resistant to BPA. The Teratogenic Index for neurula, the most sensitive embryonic stage for sublethal effects was 4.7. The main morphological alterations during early stages were: delayed or arrested development, reduced body size, persistent yolk plug, microcephaly, axial/tail flexures, edemas, blisters, waving fin, underdeveloped gills, mouth malformations, and cellular dissociation. BPA caused a remarkable narcotic effect from gill circulation stage (S.20) onwards in all the organisms exposed after 3 h of treatment with 10 mg L(-1) BPA. After recovering, the embryos exhibited scarce response to stimuli, erratic or circular swimming, and spasmodic contractions from 5 mg L(-1) onwards. Our results highlight the lethal and sublethal effectsof BPA on R. arenarum embryos and larvae, in the last case both at structural and functional levels. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

  4. Influence of Ephestia kuehniella stage larvae on the potency of Bacillus thuringiensis Cry1Aa delta-endotoxin.

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    Abdelmalek, Nouha; Sellami, Sameh; Kallassy-Awad, Mireille; Tounsi, Molka Feki; Mebarkia, Abdelkrim; Tounsi, Slim; Rouis, Souad

    2017-04-01

    The economically important crop pest Ephestia kuehniella was tested at two stages of larval development for susceptibility to Bacillus thuringiensis Cry1Aa toxin. Bioassays showed that toxicity decreased during the development of larvae stage. In fact, Cry1Aa toxins from BNS3-Cry - (pHT-cry1Aa) showed low toxicity against the first-instar larvae (L1) with a LC 50 value of about 421.02μg/g of diet and was not toxic against the fifth-instar (L5), comparing to the BLB1 toxins used as positive control which represent a LC 50 value of about 56.96 and 84.21μg/g of diet against L1 and L5 instars larvae, respectively. Effects of Cry1Aa toxins were reflected in histopathological observations by the weak destruction of midgut epithelium, slight hypertrophy of epithelial cells, and minor alteration of brush border membrane (BBM) detected mainly in L1 larvae stage comparing to the more extensive damage caused by BLB1 toxins. Interestingly, in vitro proteolysis of Cry1Aa toxins was found to correlate with the difference of toxicity during larval stage development. In fact, the weak proteinase activity detected inside the L1 midgut has led to the persistence of the Cry1Aa active forms (65 and 58kDa) during prolonged incubations, causing the alterations described previously. Three subfamilies of aminopeptidase (APN) receptors were detected in both larvae instars with different intensities and molecular weights (150kDa and 55kDa for APN1, and 90kDa for APN2 and APN4). Remarkably, binding assay using Cry1Aa toxin seems to have no direct correlation with larval stages toxicity differences, since same putative receptors were detected. Understanding the reasons for the clear differences in the effectiveness of Cry1Aa toxins during larval development stages of E. kuehniella is very important for the design of future improvement insecticidal approaches and for the accomplishment of resistance prevention strategies. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. [Morphology of III stage larvae of Angiostrongylus cantonensis in Pomacea canaliculata].

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    Zhang, Chao-Wei; Zhou, Xiao-Nong; Lv, Shan; Zhang, Yi; Liu, He-Xiang

    2008-06-30

    To observe the morphologic characteristics of III stage larvae of Angiostrongylus cantonensis from Pomacea canaliculata. P. canaliculata, the intermediate host snail of A. cantonensis, was infected with I stage larvae of A. cantonensis in laboratory. After 61 days, III stage larvae of A. cantonensis were harvested from snail's lungs and muscle of head-foot, followed by HE stain to observe morphological characteristics. The whole body of III stage larva was curling with obtuse head. Its pharyngeal canal extends from the buccal hole on the top of the head to the intestines at the pharyngeal intestine joint place, with apex cauda and clear anal tube. The tegument of the III stage larva was eosin-stained, with a transparent sheath outside of tegument. Some of the larvae cauda showed in circular cylinder, and some larvae presented ventral gland with two very short uterine which used to be the feature only showed in early IV stage larva. Morphologically characteristics of the III stage larvae is helpful to better understand the life-cycle and the control of A. cantonensis.

  6. Radiolabeling of infective third-stage larvae of Strongyloides stercoralis by feeding [75Se]selenomethionine-labeled Escherichia coli to first- and second-stage larvae

    International Nuclear Information System (INIS)

    Aikens, L.M.; Schad, G.A.

    1989-01-01

    A technique is described for radiolabeling Strongyloides stercoralis larvae with [ 75 Se]selenomethionine. Cultures of an auxotrophic methionine-dependent stain of Escherichia coli were grown in a medium containing Dulbecco's modified Eagle's medium supplemented with 5% nutrient broth, amino acids, and [ 75 Se]selenomethionine. When the 75 Se-labeled bacterial populations were in the stationary phase of growth, cultures were harvested and the bacteria dispersed on agar plates to serve as food for S. stercoralis larvae. Use of nondividing bacteria is important for successful labeling because the isotope is not diluted by cell division and death of larvae attributable to overgrowth by bacteria is prevented. First-stage S. stercoralis larvae were recovered from feces of infected dogs and reared in humid air at 30 C on agar plates seeded with bacteria. After 7 days, infective third-stage larvae were harvested. The mean specific activity of 6 different batches of larvae ranged from 75 to 330 counts per min/larva with 91.8 +/- 9.5% of the population labeled sufficiently to produce an autoradiographic focus during a practicable, 6-wk period of exposure. Labeled infective larvae penetrated the skin of 10-day-old puppies and migrated to the small intestine, where the developed to adulthood

  7. L1CAM in early-stage type I endometrial cancer: results of a large multicenter evaluation.

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    Zeimet, Alain G; Reimer, Daniel; Huszar, Monica; Winterhoff, Boris; Puistola, Ulla; Azim, Samira Abdel; Müller-Holzner, Elisabeth; Ben-Arie, Alon; van Kempen, Léon C; Petru, Edgar; Jahn, Stephan; Geels, Yvette P; Massuger, Leon F; Amant, Frédéric; Polterauer, Stephan; Lappi-Blanco, Elisa; Bulten, Johan; Meuter, Alexandra; Tanouye, Staci; Oppelt, Peter; Stroh-Weigert, Monika; Reinthaller, Alexander; Mariani, Andrea; Hackl, Werner; Netzer, Michael; Schirmer, Uwe; Vergote, Ignace; Altevogt, Peter; Marth, Christian; Fogel, Mina

    2013-08-07

    Despite the excellent prognosis of Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) stage I, type I endometrial cancers, a substantial number of patients experience recurrence and die from this disease. We analyzed the value of immunohistochemical L1CAM determination to predict clinical outcome. We conducted a retrospective multicenter cohort study to determine expression of L1CAM by immunohistochemistry in 1021 endometrial cancer specimens. The Kaplan-Meier method and Cox proportional hazard model were applied for survival and multivariable analyses. A machine-learning approach was used to validate variables for predicting recurrence and death. Of 1021 included cancers, 17.7% were rated L1CAM-positive. Of these L1CAM-positive cancers, 51.4% recurred during follow-up compared with 2.9% L1CAM-negative cancers. Patients bearing L1CAM-positive cancers had poorer disease-free and overall survival (two-sided Log-rank P relevance of these parameters was related strictly to L1CAM positivity. A classification and regression decision tree (CRT)identified L1CAM as the best variable for predicting recurrence (sensitivity = 0.74; specificity = 0.91) and death (sensitivity = 0.77; specificity = 0.89). To our knowledge, L1CAM has been shown to be the best-ever published prognostic factor in FIGO stage I, type I endometrial cancers and shows clear superiority over the standardly used multifactor risk score. L1CAM expression in type I cancers indicates the need for adjuvant treatment. This adhesion molecule might serve as a treatment target for the fully humanized anti-L1CAM antibody currently under development for clinical use.

  8. Infectivity and development of X-irradiated third-stage larvae of Angiostrongylus cantonensis in rats

    International Nuclear Information System (INIS)

    Fujiu, Yoshinori

    1989-01-01

    Angiostrongylus cantonensis third-stage larvae were exposed to less than 10Krad of X-radiation and then given orally to white rats to examine the effects of X-radiation on infectivity and development of the irradiated third-stage larvae and on fecundity of adults developing from the irradiated third-stage larvae. The deleterious effects of X-radiation were observed at relatively lower dosage in the above three parameters. A degree in susceptibility on X-radiation was shown to be radiation-dose-dependent. Comparing to the irradiation of larvae in vitro, the irradiation of larvae in snails caused less deleterious effects at the same dose of X-irradiation. Application of X-radiation to food hygiene was also discussed. (author)

  9. Differential utilization of ash phloem by emerald ash borer larvae: Ash species and larval stage effects

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    Yigen Chen; Michael D. Ulyshen; Therese M. Poland

    2012-01-01

    Two experiments were performed to determine the extent to which ash species (black, green and white) and larval developmental stage (second, third and fourth instar) affect the efficiency of phloem amino acid utilization by emerald ash borer (EAB) Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) larvae. EAB larvae generally utilized green ash...

  10. Identification of first-stage dorsal-spined lungworm larvae of Tunisian barbary red deer: First report of Varestrongylus sagittatus and Elaphostrongylus cervi in Africa.

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    Said, Yousra; Cabaret, Jacques; Harmache, Abdallah; Lahmar, Samia

    2018-03-23

    Barbary red deer (Cervus elaphus barbarus) is a protected rare subspecies of red deer. The study of its Protostrongylidae fauna based only on sporadic necropsy of naturally dead animals is difficult. Therefore diagnosis of lungworms rely mainly on the identification of the first stage larvae (L1). The L1 of the different species are not readily diagnosed on morphological basis since much variation is recorded within and among dorsal-spined larvae belonging to various species. The aim of this study was to identify the dorsal-spined lungworm larvae of the Barbary red deer. A discriminant function was established, using the measurements of L1 lungworms recorded from red deer in the literature, then applied to identify 220 dorsal-spined larvae extracted from 25 Tunisian Barbary red deer fresh fecal samples. Also the ITS2 region of rDNA of four pools of larvae (n = 25-60) were amplified, sequenced and analyzed. Using discriminant analysis of morphological traits, Elaphostrongylus cervi and Varestongylus sagittatus were identified. Molecular identification confirmed the presence of E. cervi which is the most prevalent species. This study represents the first identification of V. sagittatus and E. cervi in North Africa. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. L1CAM in Early-Stage Type I Endometrial Cancer: Results of a Large Multicenter Evaluation

    NARCIS (Netherlands)

    Zeimet, A.G.; Reimer, D.; Huszar, M.; Winterhoff, B.; Puistola, U.; Azim, S.A.; Muller-Holzner, E.; Ben-Arie, A.; Kempen, L.C.L.T. van; Petru, E.; Jahn, S.; Geels, Y.P.; Massuger, L.F.A.G.; Amant, F.; Polterauer, S.; Lappi-Blanco, E.; Bulten, J.; Meuter, A.; Tanouye, S.; Oppelt, P.; Stroh-Weigert, M.; Reinthaller, A.; Mariani, A.; Hackl, W.; Netzer, M.; Schirmer, U.; Vergote, I.; Altevogt, P.; Marth, C.; Fogel, M.

    2013-01-01

    BACKGROUND: Despite the excellent prognosis of Federation Internationale de Gynecologie et d'Obstetrique (FIGO) stage I, type I endometrial cancers, a substantial number of patients experience recurrence and die from this disease. We analyzed the value of immunohistochemical L1CAM determination to

  12. Encysted cyathostomin larvae in foals - progression of stages and the effect of seasonality.

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    Nielsen, Martin K; Lyons, Eugene T

    2017-03-15

    Cyathostomins (small strongyles) are ubiquitous in grazing horses and are known pathogens as cause of larval cyathostominosis. As part of their life cycle, cyathostomin larvae invade the mucosal walls of the large intestines and undergo encystment. Newly ingested third stage larvae are known to undergo arrested development and this can lead to an accumulation of encysted burdens over the course of a grazing season. It is believed that the host immune system plays a significant role in triggering this arrestment. Little is known about the development and progression of larval stages in foals that are not expected to mount a pronounced immune response to ingested cyathostomin larvae. This study evaluated counts of encysted larvae measured in 37 foals. The foals were born in 2013, 2014, and 2015 into a parasitology research herd kept without anthelmintic intervention and were humanely euthanatized between 50 and 293days of age as part of an ongoing parasite transmission study. A mucosal digestion technique was performed to enumerate encysted early third stage (EL3) and late third stage/fourth stage (LL3/L4) larvae in the cecum, ventral colon and dorsal colon. Counts were analyzed statistically to evaluate the influence of foal age, sex, and seasonality on the counts. Total counts as well as LL3/L4 counts were significantly higher during the grazing season (March-November). Three defined age groups (>100, 100-200, >200days) did not have statistically different counts. Male foals had significantly higher total counts compared to females, and this has not been reported before. The study found that 41% of the recovered larvae were EL3s, but no indication of arrested development of these was observed. This indicates that cyathostomin infection in foals progresses in a manner substantially different from mature horses. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Effects of starvation on moult cycle and hepatopancreas of Stage I lobster (Homarus americanus) larvae

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    Anger, K.; Storch, V.; Anger, V.; Capuzzo, J. M.

    1985-06-01

    Effects of feeding and starvation on the moult cycle and on the ultrastructure of hepatopancreas cells were studied in Stage I lobster larvae ( Homarus americanus Milne-Edwards). The relative significance of yolk and first food was quite different in larvae originating from two females. This difference was evident also in the amounts of stored lipid in the R-cells of the larval hepatopancreas. Most larvae from one hatch were, in principle, able to develop exclusively with yolk reserves (without food) to the second instar. The larvae from the second hatch showed lecithotrophic development only to the transition between late intermoult and early premoult (Stages C/D0 of Drachs's moult cycle) of the first larval instar. When initial starvation in this group lasted for 3 days or more, the point of no return (PNR) was exceeded. After the PNR, consumption of food was still possible, but development ceased in the transition C/D0 or in late premoult (D3 4). It is suggested that these stages of the moult cycle are critical points were cessation of development and increased mortality are particularly likely in early larval lobsters under nutritional stress. Examination of hepatopancreas R-cells suggested that the PNR is caused by an irreversible loss of the ability to restore lipid reserves depleted during initial starvation. Initial periods of starvation ending before the PNR prolonged mainly Stage D0 of the same instar (I). During this delay, structural changes in the R-cells caused by the preceding period of starvation were reversed: reduced lipid inclusions, swollen mitochondria, an increased number of residual bodies indicating autolysis, and a reduction of the microvillous processes. Continually starved larvae which showed lecithotrophic development throughout the first instar and were then re-fed after moulting successfully, had later a prolonged intermoult (Stage C) period in the second instar. This shows that, despite occasional lecithotrophy, food is an important

  14. Presence of Hypoderma lineatum stage I larvae in the esophagus of cattle slaughtered in Chihuahua, Chih., Mexico.

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    Quintero-Martínez, M T; Otero Negrete, J; Benítez, R; Méndez, M A; Juárez Vega, G; Cruz-Vázquez, C

    2007-05-15

    In order to detect the presence of Hypoderma lineatum stage I larvae within the esophagus of cattle slaughtered in Chihuahua, Chihuahua, Mexico, a total of five samplings were carried out between July and November 2000. In each instance, a random sample was taken from 10% of the animals slaughtered in a single work shift in each of the two slaughterhouses included in this study. The esophagus were cut longitudinally in order to carry out visual inspection and detect the presence of H. lineatum stage I larvae in the submucosa. The larvae were separated and counted. We identified the presence of H. lineatum stage I larvae in the esophagus for all sampling dates, nevertheless, within the last sampling only one esophagus had them. For all sampling dates the prevalence ranged between 11 and 33%; the latter corresponded to the sampling in October. A total of 287 esophagus was inspected of which 54 were positive with one or more larvae (19%); 233 larvae were obtained from these cases. The number of larvae recovered per sampling ranged from 46 to 74 between July and October, the highest number was found in September's sampling. The largest amount of stage I larvae per esophagus was 22 in the months of July and August. Larvae were always located in the submucosa of the esophagus and all were oriented longitudinally.

  15. Some aspects in early life stage of climbing perch, Anabas testudineus larvae

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    Ponpanom Promkaew

    2005-02-01

    volume 10 liters containing 1,000 larvae aged 1 days post-hatching (just before the mouth opened. They were fed with rotifer at a density of 10 ind/ml. Twenty larvae were collected at random from the aquarium at 2-hourly intervals, preserved in 10% buffered formalin, and then dissected to determine the presence of rotifer in the digestive tract. The digestive tracts were fixed at 32 hr of hatching at water temperatures of 27.0-30.5ºC, and measured477.63±47.80 mm in mouth height. The average number of rotifer in the digestive tract at the start of feeding was 1.50 individual/larva. A starvation experiment was carried out using a 15-liter glass aquarium (water volume 10 liters with three replications. Two hundred newly hatched larvae were kept without feeding. Larvae started to die at 216 hr and totally died within 348 hr after hatching at water temperature ranging between 27.0 and 30.5ºC. The feeding scheme experiments were done in a 15-liter glass aquarium (water volume 10 liters containing 500 of two-day old larvae (stage at first feeding. It was found that larval climbing perch aged 3- 10 days (average total length 3.02-4.97 mm consumed rotifer. The larvae of age 8-15 days (average total length 3.94-12.60 mm consumed Moina. The larvae of age 8-10 days (average total length 3.94-4.97 mmconsumed both rotifer and Moina. The larvae of age 11-day (average total length 5.51 mm consumed only Moina. The larvae of age 14-15 days (average total length 7.34-12.60 mm consumed both Moina and artificial feed. Larvae aged more than 16 days consumed only artificial feed. Determining the daily food uptake by the larvae and juveniles was done in a 15-liter glass aquarium (water volume 10 liters containing 100 larvae. The larvae consumed the living food organism i.e. rotifer or Moina depending on larval stage, with density of rotifer 100 individual/ml or with density of Moina 10 individual/ml. The amount of food intake was calculated based on changes of food density in the

  16. Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice

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    Minchul Seo

    2017-02-01

    Full Text Available Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor, the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90% upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

  17. Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice.

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    Seo, Minchul; Goo, Tae-Won; Chung, Mi Yeon; Baek, Minhee; Hwang, Jae-Sam; Kim, Mi-Ae; Yun, Eun-Young

    2017-02-28

    Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor , the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90%) upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP)-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

  18. A Robust High-Performance GPS L1 Receiver with Single-stage Quadrature Redio-Frequency Circuit

    Science.gov (United States)

    Liu, Jianghua; Xu, Weilin; Wan, Qinq; Liu, Tianci

    2018-03-01

    A low power current reuse single-stage quadrature raido-frequency part (SQRF) is proposed for GPS L1 receiver in 180nm CMOS process. The proposed circuit consists of LNA, Mixer, QVCO, is called the QLMV cell. A two blocks stacked topology is adopted in this design. The parallel QVCO and mixer placed on the top forms the upper stacked block, and the LNA placed on the bottom forms the other stacked block. The two blocks share the current and achieve low power performance. To improve the stability, a float current source is proposed. The float current isolated the local oscillation signal and the input RF signal, which bring the whole circuit robust high-performance. The result shows conversion gain is 34 dB, noise figure is three dB, the phase noise is -110 dBc/Hz at 1MHz and IIP3 is -20 dBm. The proposed circuit dissipated 1.7mW with 1 V supply voltage.

  19. Dynamics of gastropod infection by first-stage larvae of protostrongylid nematodes--a model.

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    Rezác, P; Kindlmann, P; Dostálková, I; Holasová, E

    1993-12-01

    For the description of the dynamics of snail infection by the 1st-stage larvae of protostrongylid nematodes, Skorping (1988) used the miracidia-snail model (Anderson, 1978). Here it is shown that, in contrast to miracidia, in protostrongylids the instantaneous rate of infection, alpha, is strongly dependent on the experimental design (factors like host size and size of the experimental arena). With respect to this, Anderson's model is modified by incorporation of the experimental design. The parameter alpha in its new sense as the rate of penetration (probability that the infective larva will penetrate into the host during a time unit) is shown to remain dependent, although much less so, on the experimental design. Only the inclusion of the assumed effect of mucus, which decreases the rate of penetration, yields a parameter alpha 0 (the initial rate of penetration), which is completely independent of the design of the experiment, is species-specific, and also gives the best fit to the empirical data. As the above-mentioned factors can strongly influence the value of the instantaneous rate of infection in the laboratory experiments, alpha 0 is more suitable as a measure of either the larval infectivity for the snail or snail susceptibility to infection by the protostrongylid larvae.

  20. Effect of Vaccination with Irradiated Third Stage Larvae of Haemonchus Contortus

    International Nuclear Information System (INIS)

    Beriajaya; Sukardji, P.

    2000-01-01

    The objective of this study was to determine the effect of vaccination with irradiated third stage larvae of Haemonchus contortus on immune responses in sheep. A number of 15 young male thin-tail sheep freed of worms were divided into 3 groups of 5. The first group was vaccinated with 50.000 irradiated third larvae of H. contortus . The second group was vaccinated as group 1 but without challenged. The third group was not vaccinated but challenged as group 1. Observations were carried out on egg counts, worn counts, total serum protein and antibody titer against H. contortus. The results showed there was no significant differences (P>0.05) on egg counts, worn counts and antibody titer, but a significant difference was seen on value of serum protein between vaccinated group and non vaccinated group. The results showed no protective immunity which is showed in worn counts of vaccinated and non vaccinated groups. Key word: Haemonchus contortus, irradiated larvae, sheep, vaccine

  1. Early stages of test formation in larva of Ascidia malaca (Tunicata, Ascidiacea): ultrastructural and cytochemical investigations.

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    Dolcemascolo, Giuseppe; Gianguzza, Mario

    2004-01-01

    The swimming larvae of ascidians are entirely covered by a hyalin coat called tunic, or test. This covering consists of two cuticular layers, C1 and C2, which surround an inner compartment composed of an amorphous hyalin matrix with numerous fibrils dispersed inside. Data from the literature agree on the key role played by the cells of the larval ectodermic layer in the synthesis and secretion of larval test components. In the present article are reported ultrastructural and cytochemical investigations made during test formation in the swimming larva of Ascidia malaca. Besides confirming the role played by ectodermic cells during the early stages of test formation, the investigations highlight the way in which the fibrillar component of the test is synthetized and secreted. At the ultrastructural level it has been evidenced that the C1 and C2 cuticular layers originate from the tight packing of fibrils. Based on the data reported in the present study, it is hypothesized that while a relevant part of the fibrils, once secreted, remains dispersed inside the matrix of the inner compartment of the test, quite likely in order to increase its consistency, packing of the remaining fibrils leads to the formation of the C1 and C2 cuticular layers. Packing of the fibrils in C1 and C2 could be favoured by their chemically adhesive nature. This hypothesis is strongly supported by the herewith reported results of the cytochemical investigations carried out on the test of the swimming larva of A. malaca. The cytochemical PA-TCH-SP reaction has in fact evidenced that both fibril types, i.e. those dispersed inside the inner compartment and those packed in the C1 and C2 cuticular layers, are constituted by glycoproteins and/or proteoglycans substances whose adhesive properties are well documented in the literature.

  2. New morphological data on the first-stage larvae of two Procamallanus species (Nematoda: Camallanidae) based on SEM studies.

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    Masová, Sárka; Barus, Vlastimil; Moravec, Frantisek

    2011-11-01

    First-stage larvae of camallanid nematodes Procamallanus (Procamallanus) laeviconchus (Wedl, 1862) and Procamallanus (Procamallanus) sp. from naturally infected Distichodus niloticus (Hasselquist) and Clarias gariepinus (Burchell), respectively, from Lake Turkana, Kenya (new geographical records) are described, being for the first time studied by scanning electron microscopy. Larvae of both species are characterised by the presence of a dorsal cephalic tooth, four submedian cephalic papillae and a pair of amphids, and by the elongate tail with several terminal digit-like processes. The latter formations probably serve for the attachment of larvae to the substrate in water when the larvae attract copepod intermediate hosts by their movements; these structures, especially their numbers, may be of taxonomic importance in camallanid nematodes.

  3. Diet and prey selection in late-stage larvae of five species of fish in a ...

    African Journals Online (AJOL)

    pelagic prey. All larvae selected P. hessei as a prey item. Myxus capensis and R. holubi also selected this copepod and showed the largest diversity in diet. Keywords: copepod eggs, insect larvae, larval fish assemblage, predation, seasonality

  4. ASSESSMENT OF IVERMECTIN THERAPEUTIC EFFICACY ON THIRD-STAGE LARVAE OF Lagochilascaris minor IN MICE EXPERIMENTALLY INFECTED

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Lopes BARBOSA

    1998-05-01

    Full Text Available In this study we evaluated the potential action of ivermectin on third-stage larvae, both at migratory and encysted phases, in mouse tissues after experimental infection with Lagochilascaris minor. Study groups I and II consisted of 120 mice that were orally administered 1,000 parasite eggs. In order to assess ivermectin action upon migratory larvae, group I (60 mice was equally split in three subgroups, namely I-A, I-B, and I-C. On the 7th day after inoculation (DAI, each animal from the subgroup I-A was treated with 200 µg/Kg ivermectin while subgroup I-B was given 1,000 µg/Kg, both groups received a single subcutaneous dose. To assess the drug action on encysted larvae, group II was equally split in three subgroups, namely II-A, II-B, II-C. On the 45th DAI each animal was treated with ivermectin at 200 µg/Kg (subgroup II-A and 1,000 µg/Kg (group II-B with a single subcutaneous dose. Untreated animals of subgroups I-C and II-C were used as controls. On the 60th DAI all animals were submitted to larva search. At a dose of 1,000 µg/Kg the drug had 99.5% effectiveness on third-stage migratory larvae (subgroup I-B. Ivermectin efficacy was lower than 5% on third-stage encysted larvae for both doses as well as for migratory larvae treated with 200µg/Kg.Avaliação da eficácia terapêutica da Ivermectina sobre larvas de terceiro estádio de Lagochilascaris minor em camundongos infectados experimentalmente Avaliou-se a ação da ivermectina sobre larvas de 3o estádio, tanto em fase de migração, quanto larvas encistadas em tecidos de camundongos infectados experimentalmente com Lagochilascaris minor. Foram utilizados 120 camundongos (grupos I e II, sendo que cada animal foi inoculado, por via oral, com 1.000 ovos do parasito. Para verificar a ação da ivermectina sobre larvas em migração, o grupo I (60 animais foi dividido igualmente em três subgrupos: I-A, I-B e I-C. No 7o dia após a inoculação (DAI, cada animal foi tratado com

  5. Morphology and diagnosis of some fourth-stage larvae of cyathostomines (Nematoda: Strongyloidea) in donkeys Equus asinus L. from Ethiopia.

    Science.gov (United States)

    Kharchenko, Vitaliy; Kuzmina, Tetyana; Trawford, Andrew; Getachew, Mulugeta; Feseha, Gebreab

    2009-01-01

    Fourth-stage larvae of four species of the Cyathostominae Nicoll, 1927 parasitic in donkeys Equus asinus L. from Ethiopia were identified mainly using moulting specimens. They are Cylicocyclus asini Matthee, Krecek & Gibbons, 2001, C. auriculatus (Looss, 1900) Chaves, 1930, Cyathostomum tetracanthum (Mehlis, 1831) Molin, 1861 (sensu Looss, 1900) and Cylindropharynx brevicauda Leiper, 1911. The larva of Cylicocyclus asini is similar to those of C. nassatus (Looss, 1900) Chaves, 1930 and C. leptostomum Kotlán, 1920, but differs from the former by the shape of the dorsal tooth in the oesophageal funnel, which is notably smaller than in C. asini but similar to that of C. leptostomum. However, the larva of C. asini differs from that of C. leptostomum in the size of the buccal capsule, which is notably larger than in C. leptostomum but similar to that of C. nassatus. The larva of C. auriculatus is very similar to that of C. insigne (Boulenger, 1917) Chaves, 1930. The larva of Cyathostomum tetracanthum is similar to those of Cylicostephanus bidentatus (Ihle, 1925) Lichtenfels, 1975, C. goldi (Boulenger, 1917) Lichtenfels, 1975 and Cyathostomum catinatum Looss, 1900. The larva of Cylindropharynx brevicauda is similar to that of Petrovinema skrjabini (Ershov, 1930) Ershov, 1943 but smaller in size. Including the four cyathostomine species identified in the present study, 36 species belonging to 13 genera have so far been described and identified of a total of 64 recognised and confirmed species of equine strongyles.

  6. Small larvae in large rivers: observations on downstream movement of European grayling Thymallus thymallus during early life stages.

    Science.gov (United States)

    Van Leeuwen, C H A; Dokk, T; Haugen, T O; Kiffney, P M; Museth, J

    2017-06-01

    Behaviour of early life stages of the salmonid European grayling Thymallus thymallus was investigated by assessing the timing of larval downstream movement from spawning areas, the depth at which larvae moved and the distribution of juvenile fish during summer in two large connected river systems in Norway. Trapping of larvae moving downstream and electrofishing surveys revealed that T. thymallus larvae emerging from the spawning gravel moved downstream predominantly during the night, despite light levels sufficient for orientation in the high-latitude study area. Larvae moved in the water mostly at the bottom layer close to the substratum, while drifting debris was caught in all layers of the water column. Few young-of-the-year still resided close to the spawning areas in autumn, suggesting large-scale movement (several km). Together, these observations show that there may be a deliberate, active component to downstream movement of T. thymallus during early life stages. This research signifies the importance of longitudinal connectivity for T. thymallus in Nordic large river systems. Human alterations of flow regimes and the construction of reservoirs for hydropower may not only affect the movement of adult fish, but may already interfere with active movement behaviour of fish during early life stages. © 2017 The Fisheries Society of the British Isles.

  7. Theobromine inhibits differentiation of 3T3-L1 cells during the early stage of adipogenesis via AMPK and MAPK signaling pathways.

    Science.gov (United States)

    Jang, Yeon Jeong; Koo, Hyun Jung; Sohn, Eun-Hwa; Kang, Se Chan; Rhee, Dong-Kwon; Pyo, Suhkneung

    2015-07-01

    Obesity is characterized by hypertrophy and/or by the differentiation or adipogenesis of pre-existing adipocytes. In this study, we investigated the inhibitory effects of theobromine, a type of alkaloid in cocoa, on adipocyte differentiation of 3T3-L1 preadipocytes and its mechanisms of action. Theobromine inhibited the accumulation of lipid droplets, the expression of PPARγ and C/EBPα, and the mRNA expression of aP2 and leptin. The inhibition of adipogenic differentiation by theobromine occurred primarily in the early stages of differentiation. In addition, theobromine arrested the cell cycle at the G0/G1 phase and regulated the expressions of CDK2, p27, and p21. Theobromine treatment increased AMPK phosphorylation and knockdown of AMPKα1/α2 prevented the ability of theobromine to inhibit PPARγ expression in the differentiating 3T3-L1 cells. Theobromine reduced the phosphorylation of ERK and JNK. Moreover, the secretion and the mRNA level of TNF-α and IL-6 were inhibited by theobromine treatment. These data suggest that theobromine inhibits adipocyte differentiation during the early stages of adipogenesis by regulating the expression of PPARγ and C/EBPα through the AMPK and ERK/JNK signaling pathways in 3T3-L1 preadipocytes.

  8. EVALUATION OF THE THERAPEUTIC EFFICACY OF LEVAMISOLE HYDROCHLORIDE ON THIRD-STAGE LARVAE OF Lagochilascaris minor IN EXPERIMENTALLY INFECTED MICE

    Directory of Open Access Journals (Sweden)

    Dulcinéa Maria Barbosa CAMPOS

    2016-01-01

    Full Text Available Lagochilascariosis, a disease caused by Lagochilascaris minor, affects the neck, sinuses, tonsils, lungs, the sacral region, dental alveoli, eyeballs and the central nervous system of humans. A cycle of autoinfection may occur in human host tissues characterized by the presence of eggs, larvae and adult worms. This peculiarity of the cycle hinders therapy, since there are no drugs that exhibit ovicidal, larvicidal and vermicidal activity. Given these facts, we studied the action of levamisole hydrochloride on third-stage larvae in the migration phase (G1 and on encysted larvae (G3 of L. minor. To this end, 87 inbred mice of the C57BL/6 strain were divided into test groups comprising 67 animals (G1-37; G3-30 and a control group (G2-10; G4-10 with 20 animals. Each animal was inoculated orally with 2,000 infective eggs of the parasite. The animals of the test groups were treated individually with a single oral dose of levamisole hydrochloride at a concentration of 0.075 mg. The drug was administered either 30 minutes prior to the parasite inoculation (G1 animals or 120 days after the inoculation (G3 animals. The mice in the control groups were not treated with the drug. After the time required for the migration and the encysting of L. minor larvae, all the animals were euthanized and their tissues examined. The data were analyzed using the Student's unpaired t-test and the Levene test. The groups showed no statistically significant difference. Levamisole hydrochloride was ineffective on third-stage larvae of L. minor. These findings explain the massive expulsion of live adult worms, as well as the use of long treatment schemes, owing to the persistence of larvae and eggs in human parasitic lesions.

  9. Globo H expression is associated with driver mutations and PD-L1 expressions in stage I non-small cell lung cancer.

    Science.gov (United States)

    Yang, Ching-Yao; Lin, Mong-Wei; Chang, Yih-Leong; Wu, Chen-Tu

    2017-12-12

    Globo H is a tumor-associated carbohydrate antigen exclusively expressed in cancer cells rather than normal tissue. Globo H has been found on many cancers of epithelial origins, and become an attractive target for cancer vaccine. We aimed to study the expression of Globo H in non-small cell lung cancer (NSCLC) patients, and correlated its expression with common driver mutations, clinical outcomes, and status of immune checkpoint, programmed death-ligand 1 (PD-L1). The study enrolled 228 patients with surgically resected stage I NSCLC, including 139 patients with adenocarcinoma (ADC) and 89 patients with squamous cell carcinoma (SqCC). Using immunohistochemistry, tumors with moderate to strong membranous staining in ⩾ 1% tumor cells per section were scored as positive Globo H expression. Driver mutations including EGFR, KRAS, BRAF were detected by direct sequencing, while ALK, PI3KCA, FGFR1 and PD-L1 expression was detected by immunohistochemical (IHC) staining. Positive Globo H expression was detected in 88 of the 228 (38.6%) patients. These included 51 of 139 (36.7%) patients with ADC and 37 of 89 (41.6%) patients with SqCC. Positive Globo H expression was significantly associated with EGFR mutation and PD-L1 expression in the ADC group, and PI3KCA overexpression in the SqCC group. The survival analysis showed that Globo H expression was not an independent prognostic factor in stage I NSCLC. Globo H expression was correlated with specific driver mutations in ADC and SqCC NSCLC tumors, as well as PD-L1 status. Immunotherapy targeting Globo H may have potential application in lung cancer treatment.

  10. Age matters: Developmental stage of Danio rerio larvae influences photomotor response thresholds to diazinion or diphenhydramine

    Energy Technology Data Exchange (ETDEWEB)

    Kristofco, Lauren A. [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States); Cruz, Luis Colon [Department of Anatomy and Neurobiology, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan (Puerto Rico); Haddad, Samuel P. [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States); Behra, Martine L. [Department of Anatomy and Neurobiology, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan (Puerto Rico); Chambliss, C. Kevin [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States); Department of Chemistry, Baylor University, Waco, TX (United States); Brooks, Bryan W., E-mail: Bryan_Brooks@baylor.edu [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States)

    2016-01-15

    Highlights: • Fish behavior impairments by biological active contaminants are limited yet necessary. • Aquatic toxicology assays with 0–4 dpf larval zebrafish are increasingly important. • Larval zebrafish locomotion varied with age and daylight during typical workday hours. • Photomotor behavior to diazinion and diphenhydramine differed by larval zebrafish age. • Behavioral responses of 7–10 dpf zebrafish were markedly more sensitive than 0–4 dpf. - Abstract: Because basic toxicological data is unavailable for the majority of industrial compounds, High Throughput Screening (HTS) assays using the embryonic and larval zebrafish provide promising approaches to define bioactivity profiles and identify potential adverse outcome pathways for previously understudied chemicals. Unfortunately, standardized approaches, including HTS experimental designs, for examining fish behavioral responses to contaminants are rarely available. In the present study, we examined movement behavior of larval zebrafish over 7 days (4–10 days post fertilization or dpf) during typical daylight workday hours to determine whether intrinsic activity differed with age and time of day. We then employed an early life stage approach using the Fish Embryo Test (FET) at multiple developmental ages to evaluate whether photomotor response (PMR) behavior differed with zebrafish age following exposure to diazinon (DZN), a well-studied orthophosphate insecticide, and diphenhydramine (DPH), an antihistamine that also targets serotonin reuptake transporters and the acetylcholine receptor. 72 h studies were conducted at 1–4, 4–7 and 7–10 dpf, followed by behavioral observations using a ViewPoint system at 4, 7 and 10 dpf. Distance traveled and swimming speeds were quantified; nominal treatment levels were analytically verified by isotope-dilution LC–MSMS. Larval zebrafish locomotion displayed significantly different (p < 0.05) activity profiles over the course of typical daylight and

  11. Gregariousness does not vary with geography, developmental stage, or group relatedness in feeding redheaded pine sawfly larvae.

    Science.gov (United States)

    Terbot, John W; Gaynor, Ryan L; Linnen, Catherine R

    2017-06-01

    Aggregations are widespread across the animal kingdom, yet the underlying proximate and ultimate causes are still largely unknown. An ideal system to investigate this simple, social behavior is the pine sawfly genus Neodiprion , which is experimentally tractable and exhibits interspecific variation in larval gregariousness. To assess intraspecific variation in this trait, we characterized aggregative tendency within a single widespread species, the redheaded pine sawfly ( N. lecontei ). To do so, we developed a quantitative assay in which we measured interindividual distances over a 90-min video. This assay revealed minimal behavioral differences: (1) between early-feeding and late-feeding larval instars, (2) among larvae derived from different latitudes, and (3) between groups composed of kin and those composed of nonkin. Together, these results suggest that, during the larval feeding period, the benefits individuals derive from aggregating outweigh the costs and that this cost-to-benefit ratio does not vary dramatically across space (geography) or ontogeny (developmental stage). In contrast to the feeding larvae, our assay revealed a striking reduction in gregariousness following the final larval molt in N. lecontei . We also found some intriguing interspecific variation: While N. lecontei and N. maurus feeding larvae exhibit significant aggregative tendencies, feeding N. compar larvae do not aggregate at all. These results set the stage for future work investigating the proximate and ultimate mechanisms underlying developmental and interspecific variation in larval gregariousness across Neodiprion .

  12. Variation in the diel vertical distributions of larvae and transforming stages of oceanic fishes across the tropical and equatorial Atlantic

    Science.gov (United States)

    Olivar, M. Pilar; Contreras, Tabit; Hulley, P. Alexander; Emelianov, Mikhail; López-Pérez, Cristina; Tuset, Víctor; Castellón, Arturo

    2018-01-01

    The vertical distributions of early developmental stages of oceanic fishes were investigated across the tropical and equatorial Atlantic, from oligotrophic waters close to the Brazilian coast to more productive waters close to the Mauritanian Upwelling Region. Stratification of the water column was observed throughout the study region. Fishes were caught with a MOCNESS-1 net with mouth area of 1 m2 at 11 stations. Each station was sampled both during the day and at night within a single 24-h period. The investigation covered both larvae and transforming stages from the surface to 800 m depth. Distribution patterns were analysed, and weighted mean depths for the larvae and transforming stages of each species were calculated for day and night conditions. Forty-seven different species were found. The highest number of species occurred in the three stations south of Cape Verde Islands, characterized by a mixture of South Atlantic Central Water (SACW) and Eastern North Atlantic Central Water (ENACW). There was a marked drop in species richness in the three stations closer to the African upwelling, dominated by ENACW. The highest abundances occurred in the families Myctophidae, Sternoptychidae, Gonostomatidae and Phosichthyidae. Day and night vertical distributions of larvae and transforming stages showed contrasting patterns, both in the depths of the main concentration layers in the water column, and in the diel migration patterns (where these were observed). Larvae generally showed a preference for the upper mixed layer (ca. 0-50 m) and upper thermocline (ca. 50-100 m), except for sternoptychids, which were also abundant in the lower thermocline layer (100-200 m) and even extended into the mesopelagic zone (down to 500 m). Transforming stages showed a more widespread distribution, with main concentrations in the mesopelagic zone (200-800 m). Larvae showed peak concentrations in the more illuminated and zooplankton-rich upper mixed layers during the day and a wider

  13. Changes in physicochemical properties of chitin at developmental stages (larvae, pupa and adult) of Vespa crabro (wasp).

    Science.gov (United States)

    Kaya, Murat; Sofi, Karwan; Sargin, Idris; Mujtaba, Muhammad

    2016-07-10

    It is already known that chitin in a single organism can exhibit huge differences depending on the functions it serves in different body parts, but the alterations in the characteristics of chitin in course of developmental stages of an organism still remain unknown. This study presents findings on how chitin matrix is changing physicochemically through discrete morphological stages - larva, pupa and adult - of an insect (Vespa crabro). Chitin content of the organisms were found to increase gradually as the organism grew; 2.1, 6.2 and 10.3%, with a dramatic increase in chitin deposition (nearly 3 folds) during the instar from larva to pupa. Enzymatic digestion test demonstrated that chitin isolates were close to pure. Chitin isolates were also subjected to thermal pyrolysis and no variations were observed in the thermal stability of the samples. However, it was observed that surface characteristics of chitin changed greatly as the insect grew. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. New morphological data on the first-stage larvae of two Procamallanus species (Nematoda: Camallanidae) based on SEM studies

    OpenAIRE

    Mašová Šárka; Baruš Vlastimil; Moravec František

    2011-01-01

    First-stage larvae of camallanid nematodes Procamallanus (Procamallanus) laeviconchus (Wedl, 1862) and Procamallanus (Procamallanus) sp. from naturally infected Distichodus niloticus (Hasselquist) and Clarias gariepinus (Burchell), respectively, from Lake Turkana, Kenya (new geographical records) are described, being for the first time studied by scanning electron microscopy V článku jsou popsána první stádia larev of kamlanidních hlístic Procamallanus (Procamallanus) laeviconchus (Wedl, 1...

  15. Prevalence and intensity of third stage Gnathostoma spinigerum larvae in swamp eels sold in three large markets in Bangkok, Thailand.

    Science.gov (United States)

    Saksirisampant, Wilai; Nuchprayoon, Surang; Wiwanitkit, Viroj; Kraivichian, Kanyarat; Suwansaksri, Jamsai

    2002-01-01

    Gnathostoma spinigerum is a common human tissue parasite in Thailand. The swamp eel is the major intermediate or paratenic host for this parasite. The high prevalence of the infective third stage larvae (L3) of this parasite in the rainy season has been noted in previous studies. During June 1999 (rainy season), we performed a cross-sectional survey of the prevalence and the intensity of G. spinigerum L3s in the livers of swamp eels that were obtained from three large Bangkok markets (Klong Toey, Pran Nok, and Tevej). Of a total of 785 livers, G. spinigerum L3s were found in 97: an infection rate of 12%. The prevalence rates in Klong Toey, Pran Nok, and Tevej markets were 13%, 10% and 14% respectively. There was no significant difference in the proportion of infected eels between the markets (p > 0.05). The intensity of L3 burden in the livers ranged from 1-17 larvae, with an average of 2.60 +/- 0.24 larvae (mean +/- SE). In this study a high prevalence of G. spinigerum L3s was found; there was no significant difference in the intensity of larvae in swamp eels between markets. These findings emphasize the importance of public health education: people need to be aware of the dangers of consuming raw or undercooked food.

  16. Effect of Thai 'koi-hoi' food flavoring on the viability and infectivity of the third-stage larvae of Angiostrongylus cantonensis (Nematoda: Angiostrongylidae).

    Science.gov (United States)

    Eamsobhana, Praphathip; Yoolek, Adisak; Yong, Hoi-Sen

    2010-03-01

    The effect of the food flavoring of 'koi-hoi', a popular Thai snail dish, on the viability and infectivity of Angiostrongylus (=Parastrongylus) cantonensis third-stage larvae was assessed in a mouse model. Groups of 50 each of actively moving, non-motile coiled, and extended larvae were obtained from experimentally infected snail meat, after one-hour exposure to standard 'koi-hoi' flavoring. These larvae and groups of 50 unexposed moving larvae (control) were individually fed to each group of three experimental BALB/c mice. The effect on Angiostrongylus worm burden was measured after 3 weeks of infection. Infectivity of the motile larvae after exposure to 'koi-hoi' food flavoring was 38 + or - 5.29%. This was highly significantly lower than the infectivity (62 + or - 7.21%) of the control (unexposed) third-stage larvae (chi(2) = 17.28, P food flavoring, no adult worm was recovered from the extended larvae, indicating that they were no longer alive and unable to cause infection. A small proportion (3.33 + or - 2.31%) of the coiled larvae developed into young adult worms, indicating that mobility alone is not a definitive indicator of viability. The present study confirms that the food flavoring components of 'koi-hoi' dish adversely affect the viability and infectivity of A. cantonensis larvae. Exposure of the third-stage larvae to 'koi-hoi' food flavoring resulted in decreased viability and eventually death. Prolonged treatment with food flavoring to inactivate/immobilize and then kill the infective, third-stage larvae of A. cantonensis in snail meat prior to consumption may be one of the possible economical means of reducing human infection. Copyright 2009 Elsevier B.V. All rights reserved.

  17. Some aspects in early life stage of Siamese gourami, Trichogaster pectoralis (Regan Larvae

    Directory of Open Access Journals (Sweden)

    Ponpanom Promkaew

    2005-05-01

    Full Text Available The sexual maturity of female Siamese gourami, Trichogaster pectoralis was studied by determining fecundity and gonadosomatic index (GSI. It was found that the size at sexual maturity of female Siamese gourami was 18.07±1.10 cm (mean±SD in average total length and 94.20±13.39 g in average body weight. The fecundity was 26,261±5,215.81 ova/fish and gonadosomatic index (GSI was 10.9±2.1%.Newly hatched larvae of Siamese gourami were produced by induced spawning using chemical injection (Suprefact and Motilium. The sexually mature fishes were cultured in fiber-glass tank (water volume 300 liters with the ratio of male and female brooders 1:1. The fertilization rate, hatching out and hatching rate experiments were carried out using a 15-liter aquarium (water volume 10 liters containing 1,000 eggs. It was found that the eggs were floating and rounded. The fertilized eggs had a diameter of 908.25±39.13 μm. The average fertilization rate was 91.12%, hatching out was 22 hr 10 min and average hatching rate was 83.03% at a water temperature of 27.0-30.5ºC. Sampling of the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10% buffered formalin for later analysis to determine the time of final yolk absorption. Observation using a microscope revealed that newly hatched larvae were 2.73±0.02 mm in total length and had yolk sacs of 153.76±2.49 μm3 in volume. The yolk sacs were completely absorbed within 110 hr after hatching at a water temperature of 27.0-30.5ºC. Up until full mouth development (start of feeding, 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size of mouth opening. All the larvae had open mouths about 60 hr after hatching (3.56±0.04 mm TL, with the mouths measuring 443.64±24.26 μm in height.The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters containing 1,000 larvae aged 1.5 days

  18. 1H NMR metabolic profiling of cod (Gadus morhua larvae: potential effects of temperature and diet composition during early developmental stages

    Directory of Open Access Journals (Sweden)

    Matilde Skogen Chauton

    2015-12-01

    Full Text Available Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as temperature and nutrition affects cod larvae development. Data on larvae growth and development were used together with nuclear magnetic resonance. The NMR data indicated that the temperature influenced the metabolome of the larvae; differences were related to osmolytes such as betaine/TMAO, the amino acid taurine, and creatine and lactate which reflect muscle activity. The larvae were fed Artemia from stage 2, and this was probably reflected in a high taurine content of older larvae. Larvae fed with copepods in the nutrition experiment also displayed a high taurine content, together with higher creatine and betaine/TMAO content. Data on the cod larvae metabolome should be coupled to data on gene expression, in order to identify events which are regulated on the genetic level versus regulation resulting from temperature or nutrition during development, to fully understand how the environment affects larval development.

  19. 1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages.

    Science.gov (United States)

    Chauton, Matilde Skogen; Galloway, Trina Falck; Kjørsvik, Elin; Størseth, Trond Røvik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, Ørjan; Rønnestad, Ivar; Hamre, Kristin

    2015-11-06

    Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as temperature and nutrition affects cod larvae development. Data on larvae growth and development were used together with nuclear magnetic resonance. The NMR data indicated that the temperature influenced the metabolome of the larvae; differences were related to osmolytes such as betaine/TMAO, the amino acid taurine, and creatine and lactate which reflect muscle activity. The larvae were fed Artemia from stage 2, and this was probably reflected in a high taurine content of older larvae. Larvae fed with copepods in the nutrition experiment also displayed a high taurine content, together with higher creatine and betaine/TMAO content. Data on the cod larvae metabolome should be coupled to data on gene expression, in order to identify events which are regulated on the genetic level versus regulation resulting from temperature or nutrition during development, to fully understand how the environment affects larval development. © 2015. Published by The Company of Biologists Ltd.

  20. Predictive value of PD-L1 based on mRNA level in the treatment of stage IV melanoma with ipilimumab.

    Science.gov (United States)

    Brüggemann, C; Kirchberger, M C; Goldinger, S M; Weide, B; Konrad, A; Erdmann, M; Schadendorf, D; Croner, R S; Krähenbühl, L; Kähler, K C; Hafner, C; Leisgang, W; Kiesewetter, F; Dummer, R; Schuler, G; Stürzl, M; Heinzerling, L

    2017-10-01

    PD-L1 is established as a predictive marker for therapy of non-small cell lung cancer with pembrolizumab. Furthermore, PD-L1 positive melanoma has shown more favorable outcomes when treated with anti-PD1 antibodies and dacarbazine compared to PD-L1 negative melanoma. However, the role of PD-L1 expression with regard to response to checkpoint inhibition with anti-CTLA-4 is not clear, yet. In addition, the lack of standardization in the immunohistochemical assessment of PD-L1 makes the comparison of results difficult. In this study, we investigated the PD-L1 gene expression with a new fully automated technique via RT-PCR and correlated the findings with the response to the anti-CTLA-4 antibody ipilimumab. Within a retrospective multi-center trial, PD-L1 gene expression was evaluated in 78 melanoma patients in a total of 111 pre-treatment tumor samples from 6 skin cancer centers and analyzed with regard to response to ipilimumab. For meaningful statistical analysis, the cohort was enriched for responders with 30 responders and 48 non-responders. Gene expression was assessed by quantitative RT-PCR after extracting mRNA from formalin-fixed paraffin embedded tumor tissue and correlated with results from immunohistochemical (IHC) stainings. The evaluation of PD-L1 expression based on mRNA level is feasible. Correlation between PD-L1 expression as assessed by IHC and RT-PCR showed varying levels of concordance depending on the antibody employed. RT-PCR should be further investigated to measure PD-L1 expression, since it is a semi-quantitative method with observer-independent evaluation. With this approach, there was no statistical significant difference in the PD-L1 expression between responders and non-responders to the therapy with ipilimumab. The evaluation of PD-L1 expression based on mRNA level is feasible. Correlation between PD-L1 expression as assessed by IHC and RT-PCR showed varying levels of concordance depending on the antibody employed. RT-PCR should be

  1. Population-specific genotype x genotype x environment interactions in bacterial disease of early life stages of Pacific oyster larvae.

    Science.gov (United States)

    Wendling, Carolin C; Fabritzek, Armin G; Wegner, K Mathias

    2017-04-01

    The consequences of emerging marine diseases on the evolutionary trajectories of affected host populations in the marine realm are largely unexplored. Evolution in response to natural selection depends on the genetic variation of the traits under selection and the interaction of these traits with the environment (GxE). However, in the case of diseases, pathogen genotypes add another dimension to this interaction. Therefore, the study of disease resistance needs to be extended to the interaction of host genotype, pathogen genotype and environment (GxGxE). In this study, we used a full-sib breeding design crossing two genetically differentiated populations of the Pacific oyster Crassostrea gigas (Thunberg, 1793), to determine the influence of host genotype, pathogen genotype and temperature on disease resistance. Based on a controlled infection experiment on two early life stages, that is, D-larvae and Pediveliger larvae at elevated and ambient water temperatures, we estimated disease resistance to allopatric and sympatric Vibrio sp . by measuring survival and growth within and between genetically differentiated oyster populations. In both populations, survival was higher upon infection with sympatric Vibrio sp ., indicating that disease resistance has a genetic basis and is dependent on host genotype. In addition, we observed a significant GxGxE effect in D-larvae, where contrary to expectations, disease resistance was higher at warm than at cold temperatures. Using thermal reaction norms, we could further show that disease resistance is an environment dependent trait with high plasticity, which indicates the potential for a fast acclimatization to changing environmental conditions. These population-specific reaction norms disappeared in hybrid crosses between both populations which demonstrates that admixture between genetically differentiated populations can influence GxGxE interactions on larger scales.

  2. Association of insect life stages using DNA sequences : the larvae of Philodytes umbrinus (Motschulsky) (Coleoptera : Dytiscidae)

    NARCIS (Netherlands)

    Miller, KB; Alarie, Y; Wolfe, GW; Whiting, MF

    2005-01-01

    Insect life stages are known imperfectly in many cases, and classifications are based often on only one or a few semaphoronts of a species. This is unfortunate as information in alternative life stages often is useful for scientific study. Although recent examples of DNA in taxonomy have emphasized

  3. Limnoperna fortunei Dunker, 1857 larvae in different environments of a Neotropical floodplain: relationships of abiotic variables and phytoplankton with different stages of development

    Directory of Open Access Journals (Sweden)

    J. Ernandes-Silva

    Full Text Available Abstract Limnoperna fortunei Dunker, 1857 is an Asian invasive freshwater bivalve. Although there need to contain their spread, studies about the biology of the larvae are scarce. We correlated the larval stages of L. fortunei with biotic factors such as phytoplankton and main abiotic variables in lotic environments of the Upper Paraná River floodplain. The four samples were taken quarterly during the year 2012. The Principal component analysis (PCA showed only spatial differences, as did a Canonical Correspondence Analysis (CCA. High densities of larvae were recorded in all samples the Paraná River and Baía River only in December, especially those in their initial stage. In the biovolume of Class of algae, Bacillarophyceae showed the highest value, but Chlorophycea who was strongly correlated with the density of D-stage larvae. The large variety of phytoplankton, especially microplankton Chlorophyceae, high values of PO4, NH4 and temperature were positively correlated with high densities of D-stage larvae. We conclude that high temperature, and food availability, indicated by phytoplankton community, favored the reproduction of L. fortunei and enhance the ability of specie dispersion due to the increase in the emission of propagules. Therefore, studies that address the biology of golden mussel larvae should be performed in order to prevent its spread.

  4. Lack of effects of quebracho and sainfoin hay on incoming third-stage larvae of Haemonchus contortus in goats.

    Science.gov (United States)

    Paolini, V; Prevot, F; Dorchies, Ph; Hoste, H

    2005-09-01

    The effects of tannins on adult populations of Haemonchus contortus, Trichostrongylus colubriformis and Teladorsagia circumcincta in goats are characterised mainly by a decrease in egg excretion without any significant changes in worm number. In contrast, the impact of tannins on T. colubriformis or T. circumcincta third-stage larvae (L3) is associated with a significant reduction in worm establishment. The objective of the present study was to examine the effects of quebracho extract tannins on H. contortus L3. The consequences of consumption of sainfoin hay were also examined. Twenty-one naïve kids were divided into three experimental groups. Group Q received quebracho extract and group S received sainfoin hay from days D3 to D5. Group C remained as an infected control group. All kids received 1500 L3 H. contortus on D0, D1 and D2. On D18, post-infection, the kids were slaughtered and the worm populations compared in the different groups. Compared to the control values, the worm counts decreased, respectively, by 33% and 38% in groups Q and S but the differences were not significant. No differences were found in pathophysiological measurements between the three groups. The results confirm differences in tannin effect according to nematode species but not parasitic stage.

  5. Effects of Temperature and Water Soluble Fraction of Palm Biodiesel and Diesel Fuel on Hatchability and Survival of First Stage Larvae of Macrobrachium rosenbergii

    Directory of Open Access Journals (Sweden)

    Puncharas Gorcharoenwat

    2015-01-01

    Full Text Available Effects of temperature and water soluble fraction (WSF of biodiesel and diesel on hatchability and survival of early stage Macrobrachium rosenbergii were investigated at the temperature of 25, 28, 31 and 34oC. The purpose of this study was to determine toxic effects of biodiesel and diesel on incubation period, hatchability, and survival of the first larval stage. The results showed a significant difference of incubation period among temperatures. The highest temperature (34°C resulted in the shortest incubation period (15 days while the lowest temperature (25°C gave the longest incubation period (19 days. One hundred percent of hatchability was found at temperature 28 and 31°C in the control group. The lowest hatchability occurred at 100% of WSF of palm biodiesel. The hatchability and survival of eggs through the first stage larvae in control and WSF of biodiesel decreased in higher temperature. However, in 50% WSF of diesel, the highest temperature (34°C increased the hatchability and survival whereas 100% WSF of diesel, no larval survival could be found. In comparison between WSF of biodiesel and diesel on newly hatched larvae, the diesel was more toxic to the larvae than that of the biodiesel. Regarding temperature and WSF of biodiesel and diesel effects on the first larval stage of M. rosenbergii, clearly diesel was more harmful to the larvae than biodiesel.

  6. Estimation of predation by the larvae of Toxorhynchites splendens on the aquatic stages of Aedes aegypti.

    Science.gov (United States)

    Dominic Amalraj, D; Das, P K

    1998-03-01

    Predation by instars of Toxorhynchites splendens on aquatic stages of Aedes aegypti was studied by estimating functional response parameters such as attack rate (a') and handling time (Th) in the laboratory. The predator displayed typical type-II functional response, similar to that of most insect predators when presented with increasing densities of any given size class of prey. Second instar predator attacked prey significantly at higher rate than the other instars. Small prey were attacked at higher rate than the predation on larger prey. Except second instar predator, other instars showed significant reduction in a' with increase in Th. Foraging surface area did not influence the predation rate. Predation was high at high water temperature and this was more prominent in the second instar predator. However, prey handling time was independent of the water temperature. Modeling of the predation of mixed age populations of prey and the predator through this short-term functional response experiment is discussed.

  7. Experimental infection of Radix natalensis and Culiseta longiareolata larvae with Plagiorchiid xiphidiocercariae in Egypt.

    Science.gov (United States)

    Dar, Yasser Disoky; El-Husseny, Iman Mohamad

    2013-12-01

    To clarify the life cycle of a plagiorchiid species which uses Radix natalensis as a first intermediate host for its larval development in Egypt, this study was carried out to investigate subsequent invertebrates where xiphidiocercariae of this digenean might encyst. Laboratory-bred R. natalensis and Culiseta longiareolata larvae (mosquito) were experimentally exposed to xiphidiocercariae under laboratory conditions. At 24h post-exposure, 70% of exposed juvenile R. natalensis were found harboring encysted cercariae in their tissues. In addition, C. longiareolata larvae of each developmental stage were infected with these xiphidiocercariae. Compared to unexposed mosquito larvae, a significantly higher mortality rate in first- and second-stage (L1 & L2) larvae was noted. Prevalence of infection was also significantly higher in these L1 & L2 (90% & 88%, respectively) than in third- and fourth-stage larvae. Mosquitoes emerging from exposed L1 & L2 were significantly less numerous when compared to corresponding control groups. Significant disturbance in male and female sex ratio was noted in L1- & L2-developing mosquitoes; it was equal in L1-emerging adults and slightly male biased for those coming from L2.

  8. Differential immune response of rainbow trout (Oncorhynchus mykiss) at early developmental stages (larvae and fry) against the bacterial pathogen Yersinia ruckeri

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Raida, Martin Kristian; Kania, Per Walter

    2012-01-01

    . We exposed 17 and 87 days post hatch larvae and fry (152 and 1118 degree days post hatch; avg. wt. 70 and 770 mg, respectively) to the bacterial pathogen, Yersinia ruckeri for 4 h by bath challenge. Samples were taken at 4, 24, 72 and 96 h post exposure for qPCR and immunohistochemical analyses......) and iNOS was found in infected fry when compared to the uninfected control. IgT molecules and mannose binding lectins in gills of both infected and uninfected fry were detected by immunohistochemistry. The study indicated that early life stages (yolk-sac larvae), merely up-regulate a few genes...... against broad range of pathogens. However, the increased susceptibility of older fry suggests that Y. ruckeri may utilize some of the immune elements to enter the naive fish. The up-regulation of iNOS and IL-22 in the infected larvae implicates an important role of these molecules in immune response...

  9. Larvae and a new species of Ancyronyx Erichson, 1847 (Insecta, Coleoptera, Elmidae from Palawan, Philippines, using DNA sequences for the assignment of the developmental stages

    Directory of Open Access Journals (Sweden)

    Hendrik Freitag

    2011-10-01

    Full Text Available Ancyronyx montanus sp. n. is described based on adults and larvae, matched using their cox1 DNA sequence data. Larvae of six additional species of Ancyronyx Erichson, 1847 were also described here for the first time, aided by cox1 or cob data: A. helgeschneideri Freitag & Jäch, 2007, A. minerva Freitag & Jäch, 2007, A. patrolus Freitag & Jäch, 2007, A. procerus Jäch, 1994, A. punkti Freitag & Jäch, 2007, A. pseudopatrolus Freitag & Jäch, 2007. Ancyronyx procerus is newly recorded from the Philippines by a larval specimen from Busuanga island. The new species and larval stages are described in detail and illustrated by digital and SEM images. A key to the Ancyronyx larvae of Palawan and an updated checklist of Philippine Ancyronyx is provided.

  10. Larvae and a new species of Ancyronyx Erichson, 1847 (Insecta, Coleoptera, Elmidae) from Palawan, Philippines, using DNA sequences for the assignment of the developmental stages.

    Science.gov (United States)

    Freitag, Hendrik; Balke, Michael

    2011-01-01

    Ancyronyx montanussp. n. is described based on adults and larvae, matched using their cox1 DNA sequence data. Larvae of six additional species of Ancyronyx Erichson, 1847 were also described here for the first time, aided by cox1 or cob data: Ancyronyx helgeschneideri Freitag & Jäch, 2007, Ancyronyx minerva Freitag & Jäch, 2007, Ancyronyx patrolus Freitag & Jäch, 2007, Ancyronyx procerus Jäch, 1994, Ancyronyx punkti Freitag & Jäch, 2007, Ancyronyx pseudopatrolus Freitag & Jäch, 2007. Ancyronyx procerus is newly recorded from the Philippines by a larval specimen from Busuanga island. The new species and larval stages are described in detail and illustrated by digital and SEM images. A key to the Ancyronyx larvae of Palawan and an updated checklist of Philippine Ancyronyx is provided.

  11. Determinación de las características morfológicas de larvas L1, L2 y L3 en parásitos gastrointestinales del equino en la región de los Lagos, Chile

    Directory of Open Access Journals (Sweden)

    Germán Alonso Prada Sanmiguel

    2008-06-01

    Full Text Available El presente estudio se llevó a cabo en la Región de los Lagos, Chile. La finalidad de la investigación fue determinar el tiempo de aparición y las características morfológicas de las larvas L1, L2 y L3 de grandes y pequeños estrongilos del equino, para lo cual se utilizaron 10 animales pertenecientes al predio Isla Teja de la Universidad Austral de Chile. A estos animales se les tomó una muestra de materia fecal y mediante la técnica de MacMaster se determinó el número de huevos por gramo de materia fecal, seleccionando las cuatro muestras con los conteos más altos, las cuales fueron sembradas con temperatura y humedad controlada, para ser submuestreadas cada 24 horas por un lapso de 21 días, estas submuestras se analizaron mediante la observación directa y la técnica de Baermann anotando todos los cambios tanto macro como microscópicamente. Fue posible diferenciar entre larvas L1, L2 y L3 de grandes y pequeños estróngilos, las larvas L1 de pequeños estróngilos aparecieron desde el día 2, las L2 desde el día 3 y las L3 desde el día 7.

  12. Adipocyte differentiation of 3T3-L1 preadipocytes is dependent on lipoxygenase activity during the initial stages of the differentiation process

    DEFF Research Database (Denmark)

    Madsen, Lise; Petersen, Rasmus K; Sørensen, Morten B

    2003-01-01

    (nordihydroguaiaretic acid) and the 12/15-LOX selective inhibitor baicalein. Baicalein-mediated inhibition of adipocyte differentiation was rescued by administration of rosiglitazone. Treatment with baicalein during the first 4 days of the differentiation process prevented adipocyte differentiation; supplementation...... with rosiglitazone during the same period was sufficient to rescue adipogenesis. Accordingly, we demonstrate that adipogenic conversion of 3T3-L1 cells requires PPARgamma ligands only during the first 4 days of the differentiation process. We show that the baicalein-sensitive synthesis of endogenous PPARgamma ligand...

  13. Acanthocheilonema viteae: Vaccination of jirds with irradiation-attenuated stage-3 larvae and with exported larval antigens

    International Nuclear Information System (INIS)

    Lucius, R.; Textor, G.; Kern, A.; Kirsten, C.

    1991-01-01

    Jirds (Meriones unguiculatus) were immunized with irradiated (35 krad) stage-3 larvae (L3) of Acanthocheilonema viteae. The induced resistance against homologous challenge infection and the antibody response of the animals were studied. Immunization with 3, 2, or 1 dose of 50 irradiated L3 induced approximately 90% resistance. Immunization with a single dose of only 5 irradiated L3 resulted in 60.8% protection while immunization with a single dose of 25 L3 induced 94.1% protection. The protection induced with 3 doses of 50 irradiated L3 did not decrease significantly during a period of 6 months. Sera of a proportion, but not all resistant jirds, contained antibodies against the surface of vector derived L3 as defined by IFAT. No surface antigens of microfilariae or adult worms were recognized by the sera. Vaccinated animals had antibody responses against antigens in the inner organs of L3 and in the cuticle and reproductive organs of adult worms as shown by IFAT. Immunoblotting with SDS-PAGE-separated L3 antigens and L3-CSN revealed that all sera contained antibodies against two exported antigens of 205 and 68 kDa, and against a nonexported antigen of 18 kDa. The 205-kDa antigen easily degraded into fragments of 165, 140, 125, and 105 kDa which were recognized by resistant jird sera. Various antigens of adult worms, but relatively few antigens of microfilariae, were also recognized. To test the relevance of exported antigens of L3 to resistance, jirds were immunized with L3-CSN together with a mild adjuvant. This immunization induced 67.7% resistance against challenge infection and sera of the immunized animals recognized the 205- and 68-kDa antigens of L3

  14. Genomic-bioinformatic analysis of transcripts enriched in the third-stage larva of the parasitic nematode Ascaris suum.

    Directory of Open Access Journals (Sweden)

    Cui-Qin Huang

    2008-06-01

    Full Text Available Differential transcription in Ascaris suum was investigated using a genomic-bioinformatic approach. A cDNA archive enriched for molecules in the infective third-stage larva (L3 of A. suum was constructed by suppressive-subtractive hybridization (SSH, and a subset of cDNAs from 3075 clones subjected to microarray analysis using cDNA probes derived from RNA from different developmental stages of A. suum. The cDNAs (n = 498 shown by microarray analysis to be enriched in the L3 were sequenced and subjected to bioinformatic analyses using a semi-automated pipeline (ESTExplorer. Using gene ontology (GO, 235 of these molecules were assigned to 'biological process' (n = 68, 'cellular component' (n = 50, or 'molecular function' (n = 117. Of the 91 clusters assembled, 56 molecules (61.5% had homologues/orthologues in the free-living nematodes Caenorhabditis elegans and C. briggsae and/or other organisms, whereas 35 (38.5% had no significant similarity to any sequences available in current gene databases. Transcripts encoding protein kinases, protein phosphatases (and their precursors, and enolases were abundantly represented in the L3 of A. suum, as were molecules involved in cellular processes, such as ubiquitination and proteasome function, gene transcription, protein-protein interactions, and function. In silico analyses inferred the C. elegans orthologues/homologues (n = 50 to be involved in apoptosis and insulin signaling (2%, ATP synthesis (2%, carbon metabolism (6%, fatty acid biosynthesis (2%, gap junction (2%, glucose metabolism (6%, or porphyrin metabolism (2%, although 34 (68% of them could not be mapped to a specific metabolic pathway. Small numbers of these 50 molecules were predicted to be secreted (10%, anchored (2%, and/or transmembrane (12% proteins. Functionally, 17 (34% of them were predicted to be associated with (non-wild-type RNAi phenotypes in C. elegans, the majority being embryonic lethality (Emb (13 types; 58.8%, larval arrest

  15. Key to marine arthropod larvae

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2012-03-01

    Full Text Available The scope of this key is restricted to the larvae of marine arthropods. The key is based solely on their morphology, patterns of body segmentation, numbers of appendages, and mode of locomotion. An effort has been made to treat all traditionally named larval forms, both planktonic and benthic. It is intended that this key be useful for a researcher working with archived museum specimens and therefore, does not include habitat information as a identifying trait, even though this information is usually available in the archived records. Within the phylum Arthropoda there are two sub-phyla and eleven classes having larval stages in the marineenvironment. Where feasible the original names of the various larval types have been used. Because this nomenclature is less commonly used today compared to the past, the more recent taxonomic affinities are included in parentheses after the original larval name. The key includes the following thirty-four larvae: Branchhiopoda nauplii; Cephalocarida nauplii; Mystacocarida nauplii; trilobite larva; protonymphon; hexapod larvae; Remipedia nauplii; nauplius - Y larvae; Cirripedia nauplii; Ascothoracida nauplii; Ostracoda nauplii; Euphausiacea nauplii; Penaeidea nauplii; Cyclopoida nauplii; Calanoida nauplii; Harpacticoida nauplii;Polyarthra nauplii; cypris larva; eryonecius larva; cypris-Y larva; elapthocaris larvae; mysis larvae; lucifer zoea; acetes zoea; acanthosoma larva; phyllosoma; antizoea larva; anomuran zoea; brachyuran zoea; calyptopis larvae; furcilia larva; crytopia larva; puerulus larva; alima larva.

  16. Activity of Ocimum basilicum, Ocimum canum, and Cymbopogon citratus essential oils against Plasmodium falciparum and mature-stage larvae of Anopheles funestus s.s.

    Science.gov (United States)

    Akono Ntonga, Patrick; Baldovini, Nicolas; Mouray, Elisabeth; Mambu, Lengo; Belong, Philippe; Grellier, Philippe

    2014-01-01

    The biological activities of essential oils from three plants grown in Cameroon: Ocimum basilicum, Ocimum canum, and Cymbopogon citratus were tested against Plasmodium falciparum and mature-stage larvae of Anopheles funestus. Gas chromatography and gas chromatography - mass spectrometry analyses showed that the main compounds are geranial, 1,8-cineole and linalool in C. citratus, O. canum and O. basilicum, respectively. Larvicidal tests carried out according to the protocol recommended by the World Health Organization showed that the essential oil of leaves of C. citratus is the most active against larvae of An. funestus (LC50 values = 35.5 ppm and 34.6 ppm, respectively, for larval stages III and IV after 6 h of exposure). Besides, the in vitro anti-plasmodial activity evaluated by the radioisotopic method showed that the C. citratus oil is the most active against P. falciparum, with an IC50 value of 4.2 ± 0.5 μg/mL compared with O. canum (20.6 ± 3.4 μg/mL) and O. basilicum (21 ± 4.6 μg/mL). These essential oils can be recommended for the development of natural biocides for fighting the larvae of malaria vectors and for the isolation of natural products with anti-malarial activity. © P. Akono Ntonga et al., published by EDP Sciences, 2014.

  17. Microfluidic platform for electrophysiological recordings from host-stage hookworm and Ascaris suum larvae: A new tool for anthelmintic research.

    Science.gov (United States)

    Weeks, Janis C; Roberts, William M; Robinson, Kristin J; Keaney, Melissa; Vermeire, Jon J; Urban, Joseph F; Lockery, Shawn R; Hawdon, John M

    2016-12-01

    The screening of candidate compounds and natural products for anthelmintic activity is important for discovering new drugs against human and animal parasites. We previously validated in Caenorhabditis elegans a microfluidic device ('chip') that records non-invasively the tiny electrophysiological signals generated by rhythmic contraction (pumping) of the worm's pharynx. These electropharyngeograms (EPGs) are recorded simultaneously from multiple worms per chip, providing a medium-throughput readout of muscular and neural activity that is especially useful for compounds targeting neurotransmitter receptors and ion channels. Microfluidic technologies have transformed C. elegans research and the goal of the current study was to validate hookworm and Ascaris suum host-stage larvae in the microfluidic EPG platform. Ancylostoma ceylanicum and A. caninum infective L3s (iL3s) that had been activated in vitro generally produced erratic EPG activity under the conditions tested. In contrast, A. ceylanicum L4s recovered from hamsters exhibited robust, sustained EPG activity, consisting of three waveforms: (1) conventional pumps as seen in other nematodes; (2) rapid voltage deflections, associated with irregular contractions of the esophagus and openings of the esophogeal-intestinal valve (termed a 'flutter'); and (3) hybrid waveforms, which we classified as pumps. For data analysis, pumps and flutters were combined and termed EPG 'events.' EPG waveform identification and analysis were performed semi-automatically using custom-designed software. The neuromodulator serotonin (5-hydroxytryptamine; 5HT) increased EPG event frequency in A. ceylanicum L4s at an optimal concentration of 0.5 mM. The anthelmintic drug ivermectin (IVM) inhibited EPG activity in a concentration-dependent manner. EPGs from A. suum L3s recovered from pig lungs exhibited robust pharyngeal pumping in 1 mM 5HT, which was inhibited by IVM. These experiments validate the use of A. ceylanicum L4s and A

  18. Microfluidic platform for electrophysiological recordings from host-stage hookworm and Ascaris suum larvae: A new tool for anthelmintic research

    Directory of Open Access Journals (Sweden)

    Janis C. Weeks

    2016-12-01

    Full Text Available The screening of candidate compounds and natural products for anthelmintic activity is important for discovering new drugs against human and animal parasites. We previously validated in Caenorhabditis elegans a microfluidic device (‘chip’ that records non-invasively the tiny electrophysiological signals generated by rhythmic contraction (pumping of the worm's pharynx. These electropharyngeograms (EPGs are recorded simultaneously from multiple worms per chip, providing a medium-throughput readout of muscular and neural activity that is especially useful for compounds targeting neurotransmitter receptors and ion channels. Microfluidic technologies have transformed C. elegans research and the goal of the current study was to validate hookworm and Ascaris suum host-stage larvae in the microfluidic EPG platform. Ancylostoma ceylanicum and A. caninum infective L3s (iL3s that had been activated in vitro generally produced erratic EPG activity under the conditions tested. In contrast, A. ceylanicum L4s recovered from hamsters exhibited robust, sustained EPG activity, consisting of three waveforms: (1 conventional pumps as seen in other nematodes; (2 rapid voltage deflections, associated with irregular contractions of the esophagus and openings of the esophogeal-intestinal valve (termed a ‘flutter’; and (3 hybrid waveforms, which we classified as pumps. For data analysis, pumps and flutters were combined and termed EPG ‘events.’ EPG waveform identification and analysis were performed semi-automatically using custom-designed software. The neuromodulator serotonin (5-hydroxytryptamine; 5HT increased EPG event frequency in A. ceylanicum L4s at an optimal concentration of 0.5 mM. The anthelmintic drug ivermectin (IVM inhibited EPG activity in a concentration-dependent manner. EPGs from A. suum L3s recovered from pig lungs exhibited robust pharyngeal pumping in 1 mM 5HT, which was inhibited by IVM. These experiments validate the use of A

  19. Ancyronyx Erichson, 1847 (Coleoptera, Elmidae) from Mindoro, Philippines, with description of the larvae and two new species using DNA sequences for the assignment of the developmental stages.

    Science.gov (United States)

    Freitag, Hendrik

    2013-01-01

    Ancyronyx buhid sp. n. and Ancyronyx tamaraw sp. n. are described based on adults and larvae, matched using their cox1 or cob DNA sequence data. Additional records of Ancyronyx schillhammeri Jäch, 1994 and Ancyronyx minerva Freitag & Jäch, 2007 from Mindoro are listed. The previously unknown larva of Ancyronyx schillhammeri is also described here, aided by cox1 data. The new species and larval stages are described in detail and illustrated by SEM and stacked microscopic images. Keys to the adult and larval Ancyronyx species of Mindoro and an updated checklist of Philippine Ancyronyx species are provided. The usefulness as bioindicators, the phylogenetic relationships and biogeographic aspects affecting the distribution patterns are briefly discussed.

  20. Ancyronyx Erichson, 1847 (Coleoptera, Elmidae from Mindoro, Philippines, with description of the larvae and two new species using DNA sequences for the assignment of the developmental stages

    Directory of Open Access Journals (Sweden)

    Hendrik Freitag

    2013-08-01

    Full Text Available Ancyronyx buhid sp. n. and A. tamaraw sp. n. are described based on adults and larvae, matched using their cox1 or cob DNA sequence data. Additional records of A. schillhammeri Jäch, 1994 and A. minerva Freitag & Jäch, 2007 from Mindoro are listed. The previously unknown larva of A. schillhammeri is also described here, aided by cox1 data. The new species and larval stages are described in detail and illustrated by SEM and stacked microscopic images. Keys to the adult and larval Ancyronyx species of Mindoro and an up­dated checklist of Philippine Ancyronyx species are provided. The usefulness as bioindicators, the phylogenetic relationships and biogeographic aspects affecting the distribution patterns are briefly discussed.

  1. Technology in L1

    DEFF Research Database (Denmark)

    Elf, Nikolaj Frydensbjerg; Hanghøj, Thorkild; Skaar, Håvard

    2015-01-01

    -of-school literacy practices. A final finding is the emphasis on teacher uncertainty regarding how and why to integrate technology within existing paradigms of the subject. This calls for further research on how technology may be justified in L1 practice, including various forms of teacher education.......In recent decades, several Scandinavian research projects have had an explicit focus on how technology intervenes in L1 (or so-called Mother Tongue Education) practices in Swedish, Norwegian and Danish educational contexts, and how this may impact on understanding of the subject. There is currently...... no systematic overview of the documented possibilities and challenges related to the use of technology in L1. At the same time, there is terminological confusion in use of ‘technology’ and related concepts in L1. Finally, there is a general lack of critical reflection on the relation between technological...

  2. ATG16L1

    DEFF Research Database (Denmark)

    Salem, Mohammad; Ammitzboell, Mette; Nys, Kris

    2015-01-01

    (autophagy-related 16-like 1 [S. cerevisiae]), a key component in the autophagic response to invading pathogens, have been associated with an increased risk of developing Crohn disease. The most common and well-studied genetic variant of ATG16L1 (rs2241880; leading to a T300A conversion) exhibits a strong...... association with risk for developing Crohn disease. The rs2241880 variant plays a crucial role in pathogen clearance, resulting in imbalanced cytokine production, and is linked to other biological processes, such as the endoplasmic reticulum stress/unfolded protein response. In this review, we focus......Genetic variations in the autophagic pathway influence genetic predispositions to Crohn disease. Autophagy, the major lysosomal pathway for degrading and recycling cytoplasmic material, constitutes an important homeostatic cellular process. Of interest, single-nucleotide polymorphisms in ATG16L1...

  3. Proteinases in excretory-secretory products of Toxocara canis second-stage larvae: zymography and modeling insights.

    Science.gov (United States)

    González-Páez, Gonzalo Ernesto; Alba-Hurtado, Fernando; García-Tovar, Carlos Gerardo; Argüello-García, Raúl

    2014-01-01

    Components released in excretory-secretory products of Toxocara canis larvae (TES) include phosphatidylethanolamine-binding proteins (TES26), mucins (TES120, MUC2-5), and C-type lectins (TES32, TES70) and their biochemical, immunological, and diagnostic properties have been extensively studied albeit proteinase activities towards physiological substrates are almost unknown. Proteolytic activities in TES samples were first analyzed by gel electrophoresis with gelatin as substrate. Major activities of ~400, 120, and 32 kDa in TES were relatively similar over a broad pH range (5.5-9.0) and all these were of the serine-type as leupeptin abolished gelatinolysis. Further, the ~400 kDa component degraded all physiological substrates tested (laminin, fibronectin, albumin, and goat IgG) and the 120 kDa component degraded albumin and goat IgG while proteinases of lower MW (45, 32, and 26 kDa) only degraded laminin and fibronectin, preferentially at alkaline pH (9.0). By protein modeling approaches using the known sequences of TES components, only TES26 and MUC4 displayed folding patterns significantly related to reference serine proteinases. These data suggest that most of serine proteinase activities secreted in vitro by infective larvae of T. canis have intriguing nature but otherwise help the parasite to affect multiple components of somatic organs and bodily fluids within the infected host.

  4. In vitro effects of three woody plant and sainfoin extracts on 3rd-stage larvae and adult worms of three gastrointestinal nematodes.

    Science.gov (United States)

    Paolini, V; Fouraste, I; Hoste, H

    2004-07-01

    Most studies on the effects of tanniferous plants on nematodes have examined forages but have neglected the woody plants. Therefore, in vitro effects of extracts from 3 woody plants (Rubus fructicosus, Quercus robur, Corylus avellana) have been tested on trichostrongyles and compared to sainfoin, a legume forage. Because some in vivo results indicated that the effects of tannins differed depending on the parasitic species and/or stages, the effects were measured on 3rd-stage larvae (L3) and adult worms of Teladorsagia circumcincta, Haemonchlus contortus and Trichostrongylus colubriformis. The effects of plant extracts varied according to the plant sources, the parasite species and stages. For the woody plants, significant inhibitory effects were obtained on both stages of abomasal species. Results for T. colubriformis were more variable. Effects of sainfoin extracts were significant on T. colubriformis and H. contortus L3, and on abomasal adult worms. In order to assess the implications of tannins, polyethylene glycol (PEG), an inhibitor of tannins, was added to hazel tree, oak and sainfoin extracts. Without PEG, significant inhibitory effects on L3 and adult worms were confirmed. After addition of PEG, the larval migration and motility of adult worms were restored in most cases. These results confirm variations in effects depending on factors related to plants or parasites and suggest that tannins are partly responsible for the effects.

  5. Fungi predatory activity on embryonated Toxocara canis eggs inoculated in domestic chickens (Gallus gallus domesticus) and destruction of second stage larvae.

    Science.gov (United States)

    Hiura, Emy; Del Carmen Garcia Lopes, Aline; da Paz, Jeanne Saraiva; Gava, Maylla Garschagen; Flecher, Mayra Cunha; Colares, Manuela; de Freitas Soares, Filippe Elias; da Fonseca, Leandro Abreu; Lacerda, Tracy; de Araújo, Jackson Victor; Braga, Fabio Ribeiro

    2015-09-01

    The objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2.

  6. Ultrastructural changes in the third-stage, infective larvae of ruminant nematodes treated with sainfoin (Onobrychis viciifolia) extract.

    Science.gov (United States)

    Brunet, S; Fourquaux, I; Hoste, H

    2011-12-01

    Plants rich in condensed tannins are an alternative to chemical anthelmintics to control gastrointestinal nematodes (GINs) in ruminants. Previous functional studies have shown that sainfoin extracts affect the two forms of infective larvae (L3), ensheathed and exsheathed. However, the mechanisms of action remain unknown. The aim of this study was thus to compare ultrastructural changes in ensheathed and exsheathed L3 of two GIN species after in vitro contact with sainfoin extracts using transmission electron microscopy. The main changes identified were an alteration of the hypodermis, the presence of numerous vesicles in the cytoplasm and degeneration and/or death of muscular and intestinal cells. The changes suggested similar and nonspecies-specific lesions in the two nematode species. Comparison of the modifications found in the ensheathed vs. exsheathed L3s revealed different locations of the main cellular changes depending on the larval form. It is hypothesized that these spatial differences in lesions are mainly influenced by the presence of the sheath which favors contact between the active compounds and either the cuticle or the digestive tract. Overall, our observations suggest that the functional changes observed in the biology of GIN L3s after contact with sainfoin extracts are mediated through a direct mode of action, i.e. different interactions between the bioactive plant metabolites and the nematode structure depending on the route of contact. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. The impact of environmental heterogeneity and life stage on the hindgut microbiota of Holotrichia parallela larvae (Coleoptera: Scarabaeidae.

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    Shengwei Huang

    Full Text Available Gut microbiota has diverse ecological and evolutionary effects on its hosts. However, the ways in which it responds to environmental heterogeneity and host physiology remain poorly understood. To this end, we surveyed intestinal microbiota of Holotrichia parallela larvae at different instars and from different geographic regions. Bacterial 16S rRNA gene clone libraries were constructed and clones were subsequently screened by DGGE and sequenced. Firmicutes and Proteobacteria were the major phyla, and bacteria belonging to Ruminococcaceae, Lachnospiraceae, Enterobacteriaceae, Desulfovibrionaceae and Rhodocyclaceae families were commonly found in all natural populations. However, bacterial diversity (Chao1 and Shannon indices and community structure varied across host populations, and the observed variation can be explained by soil pH, organic carbon and total nitrogen, and the climate factors (e.g., mean annual temperature of the locations where the populations were sampled. Furthermore, increases in the species richness and diversity of gut microbiota were observed during larval growth. Bacteroidetes comprised the dominant group in the first instar; however, Firmicutes composed the majority of the hindgut microbiota during the second and third instars. Our results suggest that the gut's bacterial community changes in response to environmental heterogeneity and host's physiology, possibly to meet the host's ecological needs or physiological demands.

  8. Spontaneous T-cell responses against the immune check point programmed-death-ligand 1 (PD-L1) in patients with chronic myeloproliferative neoplasms correlate with disease stage and clinical response

    DEFF Research Database (Denmark)

    Holmström, Morten Orebo; Riley, Caroline Hasselbalch; Skov, Vibe

    2018-01-01

    The Chronic Myeloproliferative Neoplasms (MPN) are cancers characterized by hyperinflammation and immune deregulation. Concurrently, the expression of the immune check point programmed death ligand 1 (PD-L1) is induced by inflammation. In this study we report on the occurrence of spontaneous T cell...... responses against a PD-L1 derived epitope in patients with MPN. We show that 71% of patients display a significant immune response against PD-L1, and patients with advanced MPN have significantly fewer and weaker PD-L1 specific immune responses compared to patients with non-advanced MPN. The PD-L1 specific...... T cell responses are CD4+ T cell responses, and by gene expression analysis we show that expression of PD-L1 is enhanced in patients with MPN. This could imply that the tumor specific immune response in MPN could be enhanced by vaccination with PD-L1 derived epitopes by boosting the anti...

  9. A complete three-dimensional reconstruction of the myoanatomy of Loricifera: comparative morphology of an adult and a Higgins larva stage.

    Science.gov (United States)

    Neves, Ricardo C; Bailly, Xavier; Leasi, Francesca; Reichert, Heinrich; Sørensen, Martin V; Kristensen, Reinhardt M

    2013-04-15

    Loricifera is a group of small, marine animals, with undetermined phylogenetic relationships within Ecdysozoa (molting protostome animals). Despite their well-known external morphology, data on the internal anatomy of loriciferans are still incomplete. Aiming to increase the knowledge of this enigmatic phylum, we reconstruct for the first time the three-dimensional myoanatomy of loriciferans. Adult Nanaloricus sp. and the Higgins larva of Armorloricus elegans were investigated with cytochemical labeling techniques and CLSM. We discuss our findings with reference to other loriciferan species and recently established phylogenies. The somatic musculature of both adult and larval stages is very complex and includes several muscles arranged in three orientations: circular, transverse and longitudinal. In adult Nanaloricus sp., the introvert is characterized by a net-like muscular arrangement, which is composed of five thin circular fibers crossed by several (up to 30) thin longitudinal fibers with bifurcated anterior ends. Two sets of muscles surround the pre-pharyngeal armature: 6 buccal tube retractors arranged 3 × 2 in a conical shaped structure, and 8 mouth cone retractors. Additionally, a thick, circular muscle marks the neck region and a putative anal sphincter is the posteriormost myoanatomical feature. In the Higgins larva of A. elegans, two circular muscles are distinguished anteriorly in the introvert: a dorsal semicircular fiber and a thin ring muscle. The posteriormost region of the body is characterized by an anal sphincter and a triangular muscle. Based on the currently available knowledge, the myoanatomical bodyplan of adult loriciferans includes: (i) 8 mouth cone retractors, (ii) a pharynx bulb composed of transversal fibers arranged radially, (iii) circular muscles of the head and neck, (iv) internal muscles of the spinoscalids, (v) longitudinal muscles spanning all body regions, and (vi) transverse (circular) muscles in the abdomen. Concerning the

  10. Comparative Evaluation of the Gut Microbiota Associated with the Below- and Above-Ground Life Stages (Larvae and Beetles) of the Forest Cockchafer, Melolontha hippocastani

    Science.gov (United States)

    Arias-Cordero, Erika; Ping, Liyan; Reichwald, Kathrin; Delb, Horst; Platzer, Mathias; Boland, Wilhelm

    2012-01-01

    A comparison of the diversity of bacterial communities in the larval midgut and adult gut of the European forest cockchafer (Melolontha hippocastani) was carried out using approaches that were both dependent on and independent of cultivation. Clone libraries of the 16S rRNA gene revealed 150 operational taxonomic units (OTUs) that belong to 11 taxonomical classes and two other groups that could be classified only to the phylum level. The most abundant classes were β, δ and γ-proteobacteria, Clostridia, Bacilli, Erysipelotrichi and Sphingobacteria. Although the insect’s gut is emptied in the prepupal stage and the beetle undergoes a long diapause period, a subset of eight taxonomic classes from the aforementioned eleven were found to be common in the guts of diapausing adults and the larval midguts (L2, L3). Moreover, several bacterial phylotypes belonging to these common bacterial classes were found to be shared by the larval midgut and the adult gut. Despite this, the adult gut bacterial community represented a subset of that found in the larvae midgut. Consequently, the midgut of the larval instars contains a more diverse bacterial community compared to the adult gut. On the other hand, after the bacteria present in the larvae were cultivated, eight bacterial species were isolated. Moreover, we found evidence of the active role of some of the bacterial species isolated in food digestion, namely, the presence of amylase and xylanolytic properties. Finally, fluorescence in situ hybridization allowed us to confirm the presence of selected species in the insect gut and through this, their ecological niche as well as the metagenomic results. The results presented here elucidated the heterogeneity of aerobic and facultative bacteria in the gut of a holometabolous insect species having two different feeding habits. PMID:23251574

  11. Comparative evaluation of the gut microbiota associated with the below- and above-ground life stages (larvae and beetles of the forest cockchafer, Melolontha hippocastani.

    Directory of Open Access Journals (Sweden)

    Erika Arias-Cordero

    Full Text Available A comparison of the diversity of bacterial communities in the larval midgut and adult gut of the European forest cockchafer (Melolontha hippocastani was carried out using approaches that were both dependent on and independent of cultivation. Clone libraries of the 16S rRNA gene revealed 150 operational taxonomic units (OTUs that belong to 11 taxonomical classes and two other groups that could be classified only to the phylum level. The most abundant classes were β, δ and γ-proteobacteria, Clostridia, Bacilli, Erysipelotrichi and Sphingobacteria. Although the insect's gut is emptied in the prepupal stage and the beetle undergoes a long diapause period, a subset of eight taxonomic classes from the aforementioned eleven were found to be common in the guts of diapausing adults and the larval midguts (L2, L3. Moreover, several bacterial phylotypes belonging to these common bacterial classes were found to be shared by the larval midgut and the adult gut. Despite this, the adult gut bacterial community represented a subset of that found in the larvae midgut. Consequently, the midgut of the larval instars contains a more diverse bacterial community compared to the adult gut. On the other hand, after the bacteria present in the larvae were cultivated, eight bacterial species were isolated. Moreover, we found evidence of the active role of some of the bacterial species isolated in food digestion, namely, the presence of amylase and xylanolytic properties. Finally, fluorescence in situ hybridization allowed us to confirm the presence of selected species in the insect gut and through this, their ecological niche as well as the metagenomic results. The results presented here elucidated the heterogeneity of aerobic and facultative bacteria in the gut of a holometabolous insect species having two different feeding habits.

  12. Increase of the Bacillus thuringiensis secreted toxicity against lepidopteron larvae by homologous expression of the vip3LB gene during sporulation stage.

    Science.gov (United States)

    Sellami, Sameh; Jamoussi, Kaïs; Dabbeche, Emna; Jaoua, Samir

    2011-09-01

    The Vegetative insecticidal Vip3A proteins display a wide range of insecticidal spectrum against several agricultural insect pests. The fact that the expression of vip3 genes occurs only during the vegetative growth phase of Bacillus thuringiensis is a limiting factor in term of production level. Therefore, extending the synthesis of the Vip proteins to the sporulation phase is a good alternative to reach high levels of toxin synthesis. In this study, we have demonstrated that the maximal production of the secreted Vip3LB (also called Vip3Aa16) during the growth of the wild-type strain B. thuringiensis BUPM 95 is reached at the end of the vegetative growth phase, and that the protein remains relatively stable in the culture supernatant during the late sporulation stages. The vip3LB gene was cloned and expressed under the control of the sporulation dependant promoters BtI and BtII in B. thuringiensis BUPM 106 (Vip3(-)) and BUPM 95 (Vip3(+)) strains. The examination of the culture supernatants during the sporulation phase evidenced the synthesis of Vip3LB and its toxicity against the second-instars larvae of the Lepidopteron insect Spodoptera littoralis for the recombinant BUPM 106. Moreover, there was an increase of the Vip3LB synthesis level and an enhancement of the oral toxicity for the recombinant BUPM 95 resulting from the expression of the vip3LB gene during both the vegetative and sporulation phases and the relative stability of the Vip3LB protein.

  13. A note on the correlation between rainfall and the prevalence of Gnathostoma spp. infective stage larvae in swamp eels in Thailand

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    Wiwanitkit V.

    2004-12-01

    Full Text Available Gnathostoma spinigerum is the major causative agent of human gnathostomiasis, a parasitic zoonosis with a great variety of clinical manifestations. Generally, humans are infected by consumption of third-stage larvae (L3 of G. spinigerum in infected hosts in the form of partially cooked or uncooked food. Surveys of the contamination of Gnathostoma spp. L3 in swamp eels are useful for prevention and control of diseases and have been continuously performed in Thailand. The author performed a retrospective study on 33 previous cross-sectional surveys with geographical data and the prevalence of Gnathostoma spp. L3 that covered 12 provinces in Thailand. The relation between rainfall (derived from the geographical data and the prevalence of Gnathostoma spp. L3 in swamp eels (derived from the overall infection rate of Gnathostoma spp. L3 was investigated. The least- square equation plot rainfall (y versus prevalence (x is y = 9.68x + 1,035.1 2 (r = 0.83; p < 0.01. A significant correlation was discerned between rainfall and the prevalence of eel infection but not for the season of the survey. Similar to the previous study, the prevalence of eel infection may depend on rainfall rather than season. However, this study focused on only 33 cross-sectional surveys in Thailand; further similar study in other countries to assess the correlation between rainfall and the prevalence of infection is required to substantiate this conclusion.

  14. Thai koi-hoi snail dish and angiostrongyliasis due to Angiostrongylus cantonensis: Effects of food flavoring and alcoholic drink on the third-stage larvae in infected snail meat.

    Science.gov (United States)

    Eamsobhana, Praphathip; Yoolek, Adisak; Punthuprapasa, Paibulaya; Yong, Hoi-Sen

    2009-04-01

    Human infection with the rat lungworm Angiostrongylus cantonensis (Parastrongylus cantonensis) in Thailand, especially in the northeastern region, is associated with the habit of eating koi-hoi, which contains raw snail meat. Infection results from the snails being carriers of the larval parasite. The present study was conducted to assess the effect of food flavorings in koi-hoi, alcohol, and exposure time of the two variable on the infective larvae of A. cantonensis. Infected Biomphalaria glabrata snails were used for koi-hoi preparation. Raw snail meat was mixed with koi-hoi flavoring and left at room temperature for various time periods ranging from 5 to 60 minutes. At a predetermined time, two pieces of snail meat were removed at random and examined for viability (as determined by motility) of the parasitic third-stage larvae. At the same time, two random pieces of snail meat were removed and treated with 10 mL of a local 40% alcoholic drink for 30 minutes before examination of larval viability. Exposure of infected snail meat for 10 minutes or more to koi-hoi food flavoring resulted in significantly more nonmotile (dying or dead) larvae. Addition of the local alcoholic drink after exposure to the flavoring exerted an additional killing effect on the larvae. Despite long exposure time, both the koi-hoi flavoring and addition of alcoholic drink were not completely effective in killing the infective larvae in the snail meat. Thorough cooking of the food intended for human consumption should still be practiced.

  15. Elevated temperatures and long drought periods have a negative impact on survival and fitness of strongylid third stage larvae.

    Science.gov (United States)

    Knapp-Lawitzke, Friederike; von Samson-Himmelstjerna, Georg; Demeler, Janina

    2016-04-01

    In grazing cattle, infections with gastrointestinal nematodes pose some of the most important health threats and subclinical infections result in considerable production losses. While there is little doubt that climate change will affect grazing ruminants directly, mean temperature increases of ∼ 3°C and longer drought stress periods in summer may also influence the free-living stages of parasitic nematodes. Hostile climatic conditions reduce the number of L3s on pasture and therefore the refugium, which is expected to result in a higher selection pressure, accelerating development of resistance against anthelmintic drugs. The aim of the current experiments was to investigate the effects of drought stress and different temperature/humidity ranges over time on the survival and fitness of Cooperia oncophora L3s and their distribution in grass and soil under controlled conditions using a climate chamber. Grass containers inoculated with L3s were analysed after 1-6weeks using descriptive statistics as well as linear models. A large proportion of L3s was recovered from soil where fitness was also better preserved than on grass. Numbers and fitness of recovered L3s declined with duration in the climate chamber under both temperature profiles. However, the results of the linear models confirmed that higher temperatures (20-33°C versus 17-22.6°C) significantly impaired survival, distribution and fitness of L3s. Application of drought stress, known as another important factor, had a surprisingly smaller impact than its duration or higher temperatures. The climate chamber enabled exclusion of confounding factors and therefore accurate interpretation of the investigated climatic aspects. The obtained results highlight the relative importance of those factors, and will help to design better models for the population dynamics of L3s on pasture in the future. Additionally, the outcomes of these investigations may offer explanations regarding interdependencies of development

  16. Third-stage Gnathostoma spinigerum larva excretory secretory antigens modulate function of Fc gamma receptor I-mediated monocytes in peripheral blood mononuclear cell culture.

    Science.gov (United States)

    Benjathummarak, Surachet; Kumsiri, Ratchanok; Nuamtanong, Supaporn; Kalambaheti, Thareerat; Waikagul, Jitra; Viseshakul, Nareerat; Maneerat, Yaowapa

    2016-01-01

    Third (infective)-stage Gnathostoma spinigerum larvae (L3) mainly cause human gnathostomiasis. G. spinigerum L3 migrate throughout the subcutaneous tissues, vital organs, and central nervous system and can cause various pathogenesis including sudden death. Interestingly, G. spinigerum L3 can survive and evade host cellular immunity for months or years. The effects of G. spinigerum excretory-secretory (ES) products involved in larval migration and immune-evasive strategies are unknown. Monocytes are innate immune cells that act as phagocytic and antigen-presenting cells and also play roles against helminthic infections via a complex interplay between other immune cells. Fc gamma receptor I (FcγRI) is a high-affinity receptor that is particularly expressed on monocytes, macrophages, and dendritic cells. The cross-linking of FcγRI and antigen-antibody complex initiates signal transduction cascades in phagocytosis, cytokine production, and antibody-dependent cell-mediated cytotoxicity (ADCC). This study investigated whether ES antigen (ESA) from G. spinigerum L3 affects monocyte functions. Cultures of normal peripheral blood mononuclear cells (PBMC) separated from healthy buffy coats were used as a human immune cell model. ESA was prepared from G. spinigerum L3 culture. Using Real-Time quantitative reverse transcription-polymerase chain reaction (qRT-PCR), the effect of ESA to down-regulate FcγRI mRNA expression in monocytes during 90 min of observation was not well delineated. Flow cytometry analysis revealed a significant phenotypic-decreased FcγRI expression on the monocyte surface at 12 hours (h) of cultivation with the ESA (p = 0.033). Significantly reduced monocyte-mediated phagocytosis capacity was consistently observed after 12 h of ESA pretreatment (p = 0.001). Our results suggest that G. spinigerum ESA modulates monocyte function via depletion of FcγRI expression. This study provides preliminary information for future in-depth studies to

  17. Transfer of L1 Visual Word Recognition Strategies during Early Stages of L2 Learning: Evidence from Hebrew Learners Whose First Language Is Either Semitic or Indo-European

    Science.gov (United States)

    Norman, Tal; Degani, Tamar; Peleg, Orna

    2016-01-01

    The present study examined visual word recognition processes in Hebrew (a Semitic language) among beginning learners whose first language (L1) was either Semitic (Arabic) or Indo-European (e.g. English). To examine if learners, like native Hebrew speakers, exhibit morphological sensitivity to root and word-pattern morphemes, learners made an…

  18. The early phyllosoma stages of spiny lobster Panulirus echinatus Smith, 1869 (Decapoda: Palinuridae reared in the laboratory

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    FA. Abrunhosa

    Full Text Available The early stages of the Panulirus echinatus were hatched and reared in the laboratory. Ovigerous females were captured in their habitat and carefully transported to the laboratory. Larvae were transferred in a recirculation water tank at a density of 10 larvae.L-1. The larvae were fed on Artemia and gonads of mussel Brachydonts sp. Microalgae Dunaliella viridis was added at a concentration of 150 x 10(4 cell.mL-1. Larvae and exuviae of each zoeal stage were preserved in an alcohol 70% + glycerin (1:1 solution. The phyllosomas moulted eight times; the intermoulting period of each instar averaged about 7 to 10 days. The main morphological changes of each appendage were described in detail, illustrated and compared with previous reports.

  19. Age of Haemonchus contortus third stage infective larvae is a factor influencing the in vitro assessment of anthelmintic properties of tannin containing plant extracts.

    Science.gov (United States)

    Castañeda-Ramírez, G S; Mathieu, C; Vilarem, G; Hoste, H; Mendoza-de-Gives, P; González-Pech, P G; Torres-Acosta, J F J; Sandoval-Castro, C A

    2017-08-30

    The larval exsheathment inhibition assay (LEIA) of infective larvae (L 3 ) is an in vitro method used to evaluate the anthelmintic (AH) activity of tannin-containing plant extracts against different species of gastrointestinal nematodes, including Haemonchus contortus. Some conditions remain to be defined in order to standardize the LEIA, i.e. the optimal age of larvae produced from donor animals to use in the assays. Therefore, this study aimed at identifying the effect of age and age-related vitality of H. contortus infective larvae produced under tropical conditions, on the in vitro AH activity measured with the LEIA. The same acetone:water (70:30) extract from Acacia pennatula leaves was used to perform respective LEIA tests with H. contortus L 3 of different ages (1-7 weeks). Each week, the L 3 were tested against different concentrations of extract (1200, 600, 400, 200, 100, 40μg/mL of extract) plus a PBS control. Bioassays were performed with a benzimidazole (Bz) resistant H. contortus (Paraíso) strain. In order to identify changes in L 3 vitality on different weeks (1-7), two assays testing larval motility were included only with PBS: the larval migration assay (LMA) and the larval motility observation assay (LMOA). Mean effective concentrations causing 50% and 90% exsheathment inhibition (EC 50 , EC 90 ) were obtained for every week using respective Probit analyses. On the first week, the larvae had lowest EC 50 and EC 90 (39.4 and 65.6μg/mL) compared to older larvae (P0.05), while older larvae tended to show higher EC 50 and EC 90 (Page of larvae (r≥-0.83; P age. More stable efficacy results were found between two to five weeks of age. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Aspectos biológicos da fase adulta de Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae oriunda de larvas alimentadas com Planococcus citri (Risso, 1813 (Hemiptera: Pseudococcidae Biological aspects of the adult stage of Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae originating from the larvae fed Planococcus citri (Risso, 1813 (Hemiptera: Pseudococcidae

    Directory of Open Access Journals (Sweden)

    Gerane Celly Dias Bezerra

    2006-08-01

    Full Text Available Objetivou-se estudar alguns aspectos biológicos da fase adulta de Chrysoperla externa (Hagen quando as larvas desse predador foram alimentadas com ninfas e fêmeas adultas de Planococcus citri (Risso. O experimento foi conduzido em câmara climatizada regulada a 25 ± 1 ºC, 70 ± 10% de UR e fotofase de 12 horas. Os adultos de C. externa cujas larvas foram alimentadas com ninfas nos três ínstares e fêmeas adultas da cochonilha, foram separados por sexo e 25 casais foram individualizados em gaiolas determinando-se a razão sexual, período de pré-oviposição, capacidade de oviposição diária e total durante 40 dias consecutivos, longevidade, período embrionário e viabilidade de ovos. Constatou-se que as ninfas nos três ínstares e fêmeas adultas fornecidas como alimento, não afetaram a razão sexual, período de pré-oviposição, período embrionário e longevidade dos adultos de C. externa. A produção diária e total de ovos por C. externa foi afetada pelo tipo de alimento fornecido ao predador durante a fase de larva, observando-se uma maior produção quando os casais foram alimentados na fase de larva com fêmeas adultas da cochonilha. Analisando-se a produção de ovos, observou-se uma maior concentração de oviposição nos primeiros dez dias do período reprodutivo, decrescendo nas avaliações seguintes. Foram obtidas porcentagens maiores de ovos viáveis e menores de inviáveis e inférteis, porém, não diferiram em função do alimento fornecido ao predador na fase de larva.It was aimed to study some biological aspects in the adult stage of Chrysoperla externa (Hagen when the larvae of predator were fed both nymphs and adult females of Planococcus citri (Risso. The experiment was conducted in climate chamber at 25 ± 1°C, 70 ± 10% of RH and 12-h photophase. The adults of C. externa whose larvae were fed nymphs at the three instars and adult females of mealybug were separated by sex and 25 couples were individualized

  1. Parasitism between Anisakis simplex (Nematoda: Anisakidae) third-stage larvae and the spotted mackerel Scomber australasicus with regard to the application of stock identification.

    Science.gov (United States)

    Chou, Yi-Ying; Wang, Chun-Shun; Chen, Hui-Guan; Chen, Hui-Yu; Chen, Shiu-Nan; Shih, Hsiu-Hui

    2011-05-11

    The nematode fauna of 369 spotted mackerel of the species Scomber australasicus, collected off the northeastern Taiwanese coast of the northwestern Pacific, was investigated monthly from April 2004 to March 2005. The following nematode species were recorded: Anisakis simplex complex, Hysterothylacium aduncum, Porrocaecum decipiens and Raphidascaris trichiuri. The seasonal variation in the infection with A. simplex third stage larva (L3) was studied throughout the 12 months. The prevalence of A. simplex L3 recorded for total fish samples was 93.6%, varying between 86.7 and 100%. There was an increase in the abundance of this nematode in spring, with the peak occurring in April. To reveal whether intrinsic factors of the spotted mackerel host contributed to infection with this nematode, fish were grouped according to their body weight, age and gonad development (reported as gonadoosomatic index, GSI), respectively, and infection parameters (i.e., prevalence, abundance and intensity) were analyzed. Results showed that abundance was significantly higher in both larger (>450 g) and older (>3 years old) fish. The gonad development of the host fish was not correlated with the intensity of the larval infection in both female and male fish. Two distinct Anisakis species were identified by PCR-RFLP, namely A. pegreffii and a recombinant genotype of A. pegreffii and A. simplex sensu stricto. These species occurred with frequencies of 97% and 3%, respectively. The usefulness of using parasites as biomarkers for spotted mackerel stock identification around Taiwanese waters was confirmed herein. A second group of 58 spotted mackerel were obtained from the coastal waters off southwestern Taiwan. In addition to the two species, A. pegreffii and the recombinant one, which were found with frequencies of 63% and 9%, respectively, an additional Anisakis species A. typica was identified with a frequency of 28% from these fish. Two spotted mackerel stocks could thus be identified based

  2. Predatory potential of Chrysoperla carnea and Cryptolaemus montrouzieri larvae on different stages of the mealybug, Phenacoccus solenopsis: a threat to cotton in South Asia.

    Science.gov (United States)

    Khan, Hafiz Azhar Ali; Sayyed, Ali H; Akram, Waseem; Raza, Sabtain; Ali, Muhammad

    2012-01-01

    The outbreaks of mealybug, Phenacoccus solenopsis Tinsley (Homoptera: Pseudococcidae), have created problems to cotton crops in South Asia in the recent years. To control this menace, predatory potential of Chrysoperla carnea and Cryptolaemus montrouzieri larvae were investigated under laboratory conditions (27 ± 5° C and 65 ± 5% RH). The experiments were conducted in no choice (only first, second, or third instar larvae of mealybug were offered at a time) and choice (first, second, and third instar larvae were offered simultaneously) feeding tests. Both predators had high consumption rates, with C. montrouzeiri being the most voracious feeder. In the no choice feeding tests, third instar larvae of C. montrouzeiri devoured the highest mean number of first instar P. solenopsis (439.38) In the choice feeding tests, a similar number of first instar nymphs (410) were consumed. In both feeding tests, C. carnea devoured relatively fewer numbers of P. solenopsis than C. montrouzeiri. Manly's preference index suggested that the both predators preferred first instar nymphs of P. solenopsis over second or third instar nymphs. Furthermore, studies on developmental rate and fecundity revealed that first instar nymphs of P. solenopsis significantly reduced development time but increased the fecundity of both predators.

  3. Experimental skin lesions from larvae of the bot fly Dermatobia hominis.

    Science.gov (United States)

    Pereira, M C; Leite, V H; Leite, A C

    2001-03-01

    Skin biopsies from larvae of Rattus norvegicus, experimentally infested with Dermatobia hominis (Linnaeus Jr) (Diptera: Cuterebridae), were processed for histopathological studies. Two days after infestation, the first-stage larvae (L1) were located deep in the dermis, surrounded by an inflamed area infiltrated predominantly by neutrophils. On the fourth day a thin necrotic layer could be seen close to the larvae, surrounded by large numbers of neutrophils, lymphocytes, macrophages with a few eosinophils and mast cells. A small warble was formed after the fourth day, increasing in size until the seventh day, when the L1 moulted to the second-stage larva (L2). The inflammatory process continued with increasing numbers of neutrophils, macrophages, lymphocytes, eosinophils and mast cells invading the area, as well as the proliferation of fibroblasts and endothelial cells and the appearance of a few localized haemorrhages. After 18-20 days, the L2 moulted to the third-stage larva (L3), when a few plasma cells could be seen in the inflamed area. At 25-30 days there was a reduction in the necrotic layer, as well as in the number of neutrophils and lymphocytes, although large amounts of eosinophils, plasma cells, and collagen fibres were seen. The L3 usually left the host after 30 days. Two days later, the larval cavity was reduced, mast cells infiltrated the region and collagen fibre production were increased. After 7 days, an intense infiltration of plasma cells and scattered necrotic areas could be seen. A scar formed after 10 days. This study showed the laboratory rat to be a suitable model for studies of D. hominis infestation.

  4. 1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages

    OpenAIRE

    Chauton, Matilde Skogen; Galloway, Trina Falck; Kj?rsvik, Elin; St?rseth, Trond R?vik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, ?rjan; R?nnestad, Ivar; Hamre, Kristin

    2015-01-01

    Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as tempera...

  5. [Dynamics of nitrogen-containing compounds in the hemolymph of 2d- and 3d-stage larvae of the reindeer warblefly (Hypodermatidae)].

    Science.gov (United States)

    Borozdina, N I

    1979-01-01

    The content of the total protein, residual and amine nitrogen, urea and ammoniac depends on the physiological state of the warble fly larvae of the reindeer. Metabolism of nitrogen-containing compounds carries out most intensively in the growing organism and during the moulting period. The moulting period is characterized by the fall in the total protein, residual and amine nitrogen and increase of the ammonias and urea.

  6. Microarray-Based Analysis of Differential Gene Expression between Infective and Noninfective Larvae of Strongyloides stercoralis

    Science.gov (United States)

    Ramanathan, Roshan; Varma, Sudhir; Ribeiro, José M. C.; Myers, Timothy G.; Nolan, Thomas J.; Abraham, David; Lok, James B.; Nutman, Thomas B.

    2011-01-01

    Background Differences between noninfective first-stage (L1) and infective third-stage (L3i) larvae of parasitic nematode Strongyloides stercoralis at the molecular level are relatively uncharacterized. DNA microarrays were developed and utilized for this purpose. Methods and Findings Oligonucleotide hybridization probes for the array were designed to bind 3,571 putative mRNA transcripts predicted by analysis of 11,335 expressed sequence tags (ESTs) obtained as part of the Nematode EST project. RNA obtained from S. stercoralis L3i and L1 was co-hybridized to each array after labeling the individual samples with different fluorescent tags. Bioinformatic predictions of gene function were developed using a novel cDNA Annotation System software. We identified 935 differentially expressed genes (469 L3i-biased; 466 L1-biased) having two-fold expression differences or greater and microarray signals with a p valuemicroarray tool for the examination of S. stercoralis biology has been developed and provides new and valuable insights regarding differences between infective and noninfective S. stercoralis larvae. Potential therapeutic and vaccine targets were identified for further study. PMID:21572524

  7. Metabolic rate regulates L1 longevity in C. elegans.

    Directory of Open Access Journals (Sweden)

    Inhwan Lee

    Full Text Available Animals have to cope with starvation. The molecular mechanisms by which animals survive long-term starvation, however, are not clearly understood. When they hatch without food, C. elegans arrests development at the first larval stage (L1 and survives more than two weeks. Here we show that the survival span of arrested L1s, which we call L1 longevity, is a starvation response regulated by metabolic rate during starvation. A high rate of metabolism shortens the L1 survival span, whereas a low rate of metabolism lengthens it. The longer worms are starved, the slower they grow once they are fed, suggesting that L1 arrest has metabolic costs. Furthermore, mutants of genes that regulate metabolism show altered L1 longevity. Among them, we found that AMP-dependent protein kinase (AMPK, as a key energy sensor, regulates L1 longevity by regulating this metabolic arrest. Our results suggest that L1 longevity is determined by metabolic rate and that AMPK as a master regulator of metabolism controls this arrest so that the animals survive long-term starvation.

  8. Biolarvacidal activity of methanol extract of Kipahit leaves (Tithonia diversifolia against larvae of Chrysomya bezziana fly

    Directory of Open Access Journals (Sweden)

    Wardhana AH

    2014-03-01

    Full Text Available Myiasis or “belatungan” is the infestation of live human and vertebrate animal tissue with dipterous larvae, Chrysomya bezziana. In general, synthetic insecticides were applied to control the disease. However, it causes negative impact on animal product, so that it is required to find an alternative treatment using herbal medicine. The aim of this study was to access activity of methanol extract of Kipahit leaves (Tithonia diversifolia against various stages of C. bezziana larvae (L1, L2 and L3. Five treatments were applied with five replications, i.e. control/water (P0, 0,5%, 1%, 2% of the extract for PI, PII and PIII, respectively. Another treatment was 0,05% Asuntol for positive control (PIV. Each treatment was added with1% DMSO and twenty larvae were examined for each replication. Bioassay of L1 and L2 was addressed to investigate effect of intestinal toxicity by mixing the extract with Meat-Blood Mixture (MBM and Larval Rearing Media (LRM for L1 and L2, respectively. Bioassay of L3 was to investigate effect of contact toxicity through soaking the larvae into the extract solution for 10 seconds followed by incubating in vermiculite at 36oC. All living larvae after being treated by various concentration of the extract were reared to pupae and allowed to emerge as imago. Number of living larvae and pupae, pupae weight and number of imago were observed. All data were analysed using ANOVA followed by Dunnett test at 95% confidential limit. For L2, larval mortality were counted and probit analysed using POLO-PC software, therefore the lethal concentration (LC50 and LC95 and lethal time (LT50 and LT95 were defined. Results demonstrated that 1% of the extract was the most effective concentration which was able to kill the larvae and decrease the pupae weight. It also caused to fail pupation and imago emergence. The further study might be pursued to investigate in vivo assay of the extract in infested livestock.

  9. Mucous Secretion and Cilia Beating Defend Developing Coral Larvae from Suspended Sediments.

    Directory of Open Access Journals (Sweden)

    Gerard F Ricardo

    Full Text Available Suspended sediments produced from dredging activities, or added to the sediment budget via river runoff, are a concern for marine resource managers. Understanding the impact of suspended sediments on critical life history stages of keystone species like corals is fundamental to effective management of coastlines and reefs. Coral embryos (Acropora tenuis and A. millepora and larvae (A. tenuis, A. millepora and Pocillopora acuta were subjected to a range of suspended sediment concentrations of different sediment types (siliciclastic and carbonate to assess concentration-response relationships on ecologically relevant endpoints, including survivorship and ability to metamorphose. Embryos were subjected to short (12 h suspended sediment exposures from ages of 3-12 hours old or a long (30 h exposure at 6 hours old. Neither the survivorship nor metamorphosis function of embryos were significantly affected by realistic sediment exposures to ~1000 mg L-1. However, some embryos exhibited a previously undescribed response to dynamically suspended sediments, which saw 10% of the embryos form negatively buoyant cocoons at siliciclastic suspended sediment concentrations ≥35 mg L-1. Scanning electron and optical microscopy confirmed the presence of a coating on these embryos, possibly mucus with incorporated sediment particles. Cocoon formation was common in embryos but not in larvae, and occurred more often after exposure to siliciclastic rather than carbonate sediments. Once transferred into sediment-free seawater, functional ~36-h-old embryos began emerging from the cocoons, coinciding with cilia development. Ciliated (> 36-h-old larvae exposed to suspended sediments for 60 h were also observed to secrete mucus and were similarly unaffected by suspended sediment concentrations to ~800 mg L-1. This study provides evidence that mucous secretion and cilia beating effectively protect coral embryos and larvae from suspended sediment and that these mechanisms

  10. PD-L1-specific T cells

    DEFF Research Database (Denmark)

    Ahmad, Shamaila Munir; Borch, Troels Holz; Hansen, Morten

    2016-01-01

    -specific T cells that recognize both PD-L1-expressing immune cells and malignant cells. Thus, PD-L1-specific T cells have the ability to modulate adaptive immune reactions by reacting to regulatory cells. Thus, utilization of PD-L1-derived T cell epitopes may represent an attractive vaccination strategy...... for targeting the tumor microenvironment and for boosting the clinical effects of additional anticancer immunotherapy. This review summarizes present information about PD-L1 as a T cell antigen, depicts the initial findings about the function of PD-L1-specific T cells in the adjustment of immune responses...

  11. The prognostic value of cancer stem-like cell markers SOX2 and CD133 in stage III colon cancer is modified by expression of the immune-related markers FoxP3, PD-L1 and CD3.

    Science.gov (United States)

    Miller, T J; McCoy, M J; Hemmings, C; Bulsara, M K; Iacopetta, B; Platell, C F

    2017-12-01

    Cancer stem-like cells are highly tumourigenic cells that can repopulate entire tumours after apparent successful treatment. Recent evidence suggests they interact with other cells in the tumour microenvironment, including immune cell subsets, to enhance their survival. The aim of this study was to determine whether the expression of immune cell markers in primary colon cancer impacts the prognostic significance of cancer stem-like cell marker expression. Immunohistochemistry was used to assess the expression of putative stem cell markers (ALDH1, CD44v6, CD133, Lgr5, SOX2) and immune cell related markers (CD3, CD8, FoxP3, PD-L1) in 104 patients with stage III colon cancer. Associations of marker expression with overall and cancer-specific survival were determined using Kaplan-Meier analysis. High SOX2 expression in the central tumour area was found to be an independent factor for poor cancer-specific survival [hazard ratio (HR) 6.19; 95% confidence interval (CI) 2.24-17.14; p=0.001]. When immune-related factors were taken into account, patients categorised as SOX2 low /FoxP3 high had good outcome (HR 0.164; 95%CI 0.066-0.406; p<0.0001) whereas patients categorised as SOX2 high /PD-L1 low had poor outcome (HR 8.992; 95%CI 3.397-23.803; p<0.0001). The prognostic value of the SOX2 cancer stem-like cell marker in colon cancer is modified by expression of immune-cell related factors FoxP3 and PD-L1. Copyright © 2017 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.

  12. Larvae for layers

    DEFF Research Database (Denmark)

    Bjerrum, Lotte; Fischer, Christian Holst; Nordentoft, Steen

    2013-01-01

    Companies and researchers are in close collaboration developing a container- based system for cultivating fly larvae at organic poultry farms. In a one week process, manure will be converted to compost and the live larvae will be harvested and used for feeding laying hens. The larvae are expected...

  13. A Phosphorylcholine-Containing Glycolipid-like Antigen Present on the Surface of Infective Stage Larvae of Ascaris spp. Is a Major Antibody Target in Infected Pigs and Humans

    Science.gov (United States)

    Masure, Dries; Wang, Tao; Nejsum, Peter; Hokke, Cornelis H.; Geldhof, Peter

    2016-01-01

    Background The pig parasite Ascaris suum plays and important role in veterinary medicine and represents a suitable model for A. lumbricoides, which infects over 800 million people. In pigs, continued exposure to Ascaris induces immunity at the level of the gut, protecting the host against migrating larvae. The objective of this study was to identify and characterize parasite antigens targeted by this local immune response that may be crucial for parasite invasion and establishment and to evaluate their protective and diagnostic potential. Methodology/Principal Findings Pigs were immunized by trickle infection for 30 weeks, challenged with 2,000 eggs at week 32 and euthanized two weeks after challenge. At necropsy, there was a 100% reduction in worms recovered from the intestine and a 97.2% reduction in liver white spots in comparison with challenged non-immune control animals. Antibodies purified from the intestinal mucus or from the supernatant of cultured antibody secreting cells from mesenteric lymph nodes of immune pigs were used to probe L3 extracts to identify antibody targets. This resulted in the recognition of a 12kDa antigen (As12) that is actively shed from infective Ascaris L3. As12 was characterized as a phosphorylcholine-containing glycolipid-like antigen that is highly resistant to different enzymatic and chemical treatments. Vaccinating pigs with an As12 fraction did not induce protective immunity to challenge infection. However, serological analysis using sera or plasma from experimentally infected pigs or naturally infected humans demonstrated that the As12 ELISA was able to detect long-term exposure to Ascaris with a high diagnostic sensitivity (98.4% and 92%, respectively) and specificity (95.5% and 90.0%) in pigs and humans, respectively. Conclusions/Significance These findings show the presence of a highly stage specific, glycolipid-like component (As12) that is actively secreted by infectious Ascaris larvae and which acts as a major antibody

  14. A Phosphorylcholine-Containing Glycolipid-like Antigen Present on the Surface of Infective Stage Larvae of Ascaris spp. Is a Major Antibody Target in Infected Pigs and Humans.

    Science.gov (United States)

    Vlaminck, Johnny; Masure, Dries; Wang, Tao; Nejsum, Peter; Hokke, Cornelis H; Geldhof, Peter

    2016-12-01

    The pig parasite Ascaris suum plays and important role in veterinary medicine and represents a suitable model for A. lumbricoides, which infects over 800 million people. In pigs, continued exposure to Ascaris induces immunity at the level of the gut, protecting the host against migrating larvae. The objective of this study was to identify and characterize parasite antigens targeted by this local immune response that may be crucial for parasite invasion and establishment and to evaluate their protective and diagnostic potential. Pigs were immunized by trickle infection for 30 weeks, challenged with 2,000 eggs at week 32 and euthanized two weeks after challenge. At necropsy, there was a 100% reduction in worms recovered from the intestine and a 97.2% reduction in liver white spots in comparison with challenged non-immune control animals. Antibodies purified from the intestinal mucus or from the supernatant of cultured antibody secreting cells from mesenteric lymph nodes of immune pigs were used to probe L3 extracts to identify antibody targets. This resulted in the recognition of a 12kDa antigen (As12) that is actively shed from infective Ascaris L3. As12 was characterized as a phosphorylcholine-containing glycolipid-like antigen that is highly resistant to different enzymatic and chemical treatments. Vaccinating pigs with an As12 fraction did not induce protective immunity to challenge infection. However, serological analysis using sera or plasma from experimentally infected pigs or naturally infected humans demonstrated that the As12 ELISA was able to detect long-term exposure to Ascaris with a high diagnostic sensitivity (98.4% and 92%, respectively) and specificity (95.5% and 90.0%) in pigs and humans, respectively. These findings show the presence of a highly stage specific, glycolipid-like component (As12) that is actively secreted by infectious Ascaris larvae and which acts as a major antibody target in infected humans and pigs.

  15. A Phosphorylcholine-Containing Glycolipid-like Antigen Present on the Surface of Infective Stage Larvae of Ascaris spp. Is a Major Antibody Target in Infected Pigs and Humans.

    Directory of Open Access Journals (Sweden)

    Johnny Vlaminck

    2016-12-01

    Full Text Available The pig parasite Ascaris suum plays and important role in veterinary medicine and represents a suitable model for A. lumbricoides, which infects over 800 million people. In pigs, continued exposure to Ascaris induces immunity at the level of the gut, protecting the host against migrating larvae. The objective of this study was to identify and characterize parasite antigens targeted by this local immune response that may be crucial for parasite invasion and establishment and to evaluate their protective and diagnostic potential.Pigs were immunized by trickle infection for 30 weeks, challenged with 2,000 eggs at week 32 and euthanized two weeks after challenge. At necropsy, there was a 100% reduction in worms recovered from the intestine and a 97.2% reduction in liver white spots in comparison with challenged non-immune control animals. Antibodies purified from the intestinal mucus or from the supernatant of cultured antibody secreting cells from mesenteric lymph nodes of immune pigs were used to probe L3 extracts to identify antibody targets. This resulted in the recognition of a 12kDa antigen (As12 that is actively shed from infective Ascaris L3. As12 was characterized as a phosphorylcholine-containing glycolipid-like antigen that is highly resistant to different enzymatic and chemical treatments. Vaccinating pigs with an As12 fraction did not induce protective immunity to challenge infection. However, serological analysis using sera or plasma from experimentally infected pigs or naturally infected humans demonstrated that the As12 ELISA was able to detect long-term exposure to Ascaris with a high diagnostic sensitivity (98.4% and 92%, respectively and specificity (95.5% and 90.0% in pigs and humans, respectively.These findings show the presence of a highly stage specific, glycolipid-like component (As12 that is actively secreted by infectious Ascaris larvae and which acts as a major antibody target in infected humans and pigs.

  16. The First Paenibacillus larvae Bacteriophage Endolysin (PlyPl23 with High Potential to Control American Foulbrood.

    Directory of Open Access Journals (Sweden)

    Ana Oliveira

    Full Text Available Endolysins, which are peptidoglycan-degrading enzymes expressed during the terminal stage of the reproduction cycle of bacteriophages, have great potential to control Gram-positive pathogens. This work describes the characterization of a novel endolysin (PlyPl23 encoded on the genome of Paenibacillus larvae phage phiIBB_Pl23 with high potential to control American foulbrood. This bacterial disease, caused by P. larvae, is widespread in North America and Europe and causes important economic losses in apiculture. The restriction to antibiotic residues in honey imposed by the EU legislation hinders its therapeutic use to combat American foulbrood and enforces the development of alternative antimicrobial methods. The new endolysin described herein has an N-acetylmuramoyl-L-alanine amidase catalytic domain and exhibits a broad-spectrum activity against common P. larvae genotypes. Moreover, the enzyme displays high antimicrobial activity in a range of pH that matches environmental conditions (pH between 5.0 and 7.0, showing its feasible application in the field. At pH 7.0, a concentration of 0.2 μM of enzyme was enough to lyse 104 CFU.mL-1 of P. larvae in no more than 2 h. The presence of sucrose and of the substances present in the larvae gut content did not affect the enzyme activity. Interestingly, an increase of activity was observed when PlyPl23 was previously incubated in royal jelly. Furthermore, in vivo safety evaluation assays demonstrated that this enzyme is not toxic to the bee larvae. The present work describes for the first time an endolysin encoded in a P. larvae phage that presents high potential to integrate a commercial product to control the problematic American foulbrood.

  17. The First Paenibacillus larvae Bacteriophage Endolysin (PlyPl23) with High Potential to Control American Foulbrood.

    Science.gov (United States)

    Oliveira, Ana; Leite, Marta; Kluskens, Leon D; Santos, Sílvio B; Melo, Luís D R; Azeredo, Joana

    2015-01-01

    Endolysins, which are peptidoglycan-degrading enzymes expressed during the terminal stage of the reproduction cycle of bacteriophages, have great potential to control Gram-positive pathogens. This work describes the characterization of a novel endolysin (PlyPl23) encoded on the genome of Paenibacillus larvae phage phiIBB_Pl23 with high potential to control American foulbrood. This bacterial disease, caused by P. larvae, is widespread in North America and Europe and causes important economic losses in apiculture. The restriction to antibiotic residues in honey imposed by the EU legislation hinders its therapeutic use to combat American foulbrood and enforces the development of alternative antimicrobial methods. The new endolysin described herein has an N-acetylmuramoyl-L-alanine amidase catalytic domain and exhibits a broad-spectrum activity against common P. larvae genotypes. Moreover, the enzyme displays high antimicrobial activity in a range of pH that matches environmental conditions (pH between 5.0 and 7.0), showing its feasible application in the field. At pH 7.0, a concentration of 0.2 μM of enzyme was enough to lyse 104 CFU.mL-1 of P. larvae in no more than 2 h. The presence of sucrose and of the substances present in the larvae gut content did not affect the enzyme activity. Interestingly, an increase of activity was observed when PlyPl23 was previously incubated in royal jelly. Furthermore, in vivo safety evaluation assays demonstrated that this enzyme is not toxic to the bee larvae. The present work describes for the first time an endolysin encoded in a P. larvae phage that presents high potential to integrate a commercial product to control the problematic American foulbrood.

  18. Toxicity of cadmium for silver catfish Rhamdia quelen (Heptapteridae) embryos and larvae at different alkalinities.

    Science.gov (United States)

    Benaduce, Ana Paula S; Kochhann, Daiani; Flores, Erico M M; Dressler, Valderi L; Baldisserotto, Bernardo

    2008-02-01

    The present study evaluated the effect of waterborne Cd in eggs and larvae of silver catfish, Rhamdia quelen, at two alkalinity levels (63 and 92 mg . L(-1) CaCO(3)): 0.5 (control), 4.5, 8, and 18 microg . L(-1) Cd. The fertilization rate was similar in all treatments, but the number of eggs with irregular surface was significantly higher in those exposed to 18 microg . L(-1) Cd and 63 mg . L(-1) CaCO(3). Three days after hatching survival of larvae exposed to 4.5 and 8 microg . L(-1) Cd and 63 mg . L(-1) CaCO(3) was significantly lower than that of control larvae, and 21 days after hatching survival decreased with the increase in waterborne Cd levels and total cadmium accumulation in the larvae. These significant differences and relationships were not observed in larvae maintained at 92 mg . L(-1) CaCO(3). Furthermore, in the lower alkalinity, a higher incidence of barbels and spinal column deformities was observed in the highest waterborne Cd concentration. At the end of the experimental period, 21 days after hatching, larval survival rate, length, weight, head height, membranous layer thickness, and biomass decreased with the increase in waterborne Cd levels in the lower alkalinity. However, these relationships were not observed in larvae maintained at 92 mg . L(-1) CaCO(3). The percentage specific growth rate was lower in larvae exposed to the highest waterborne Cd concentration at 63 mg . L(-1) CaCO(3). These results suggest that alkalinity of 92 mg . L(-1) CaCO(3) reduces waterborne Cd toxicity in silver catfish larvae.

  19. Proteolytic activity in the adult and larval stages of the human roundworm parasite Angiostrongylus costaricensis

    Directory of Open Access Journals (Sweden)

    Karina Mastropasqua Rebello

    2012-09-01

    Full Text Available Angiostrongylus costaricensis is a nematode that causes abdominal angiostrongyliasis, a widespread human parasitism in Latin America. This study aimed to characterize the protease profiles of different developmental stages of this helminth. First-stage larvae (L1 were obtained from the faeces of infected Sigmodon hispidus rodents and third-stage larvae (L3 were collected from mollusks Biomphalaria glabrata previously infected with L1. Adult worms were recovered from rodent mesenteric arteries. Protein extraction was performed after repeated freeze-thaw cycles followed by maceration of the nematodes in 40 mM Tris base. Proteolysis of gelatin was observed by zymography and found only in the larval stages. In L3, the gelatinolytic activity was effectively inhibited by orthophenanthroline, indicating the involvement of metalloproteases. The mechanistic class of the gelatinases from L1 could not be precisely determined using traditional class-specific inhibitors. Adult worm extracts were able to hydrolyze haemoglobin in solution, although no activity was observed by zymography. This haemoglobinolytic activity was ascribed to aspartic proteases following its effective inhibition by pepstatin, which also inhibited the haemoglobinolytic activity of L1 and L3 extracts. The characterization of protease expression throughout the A. costaricensis life cycle may reveal key factors influencing the process of parasitic infection and thus foster our understanding of the disease pathogenesis.

  20. Voice and Narrative in L1 Writing

    DEFF Research Database (Denmark)

    Krogh, Ellen; Piekut, Anke

    2015-01-01

    This paper investigates issues of voice and narrative in L1 writing. Three branches of research are initial-ly discussed: research on narratives as resources for identity work, research on writer identity and voice as an essential aspect of identity, and research on Bildung in L1 writing...... in lower secondary L1, she found that her previous writing strategies were not rewarded in upper secondary school. In the second empiri-cal study, two upper-secondary exam papers are investigated, with a focus on their approaches to exam genres and their use of narrative resources to address issues....... Subsequently, two empirical investigations of L1 writing in a Danish upper secondary school are presented. The first study is based on longitudinal interview data and analyses one student’s experience as an L1 writer in the transition from lower secondary to upper secondary school. A high-achieving student...

  1. Early developmental stages of Ascaris lumbricoides featured by high-resolution mass spectrometry.

    Science.gov (United States)

    Melo, Carlos Fernando Odir Rodrigues; Esteves, Cibele Zanardi; de Oliveira, Rosimeire Nunes; Guerreiro, Tatiane Melina; de Oliveira, Diogo Noin; Lima, Estela de Oliveira; Miné, Júlio César; Allegretti, Silmara Marques; Catharino, Rodrigo Ramos

    2016-11-01

    Ascaris lumbricoides is responsible for a highly disseminated helminth parasitic disease, ascariosis, a relevant parasitosis that responds for great financial burden on the public health system of developing countries. In this work, metabolic fingerprinting using high-resolution mass spectrometry (HRMS) was employed to identify marker molecules from A. lumbricoides in different development stages. We have identified nine biomarkers, such as pheromones and steroidal prohormones in early stages, among other molecules in late development stages, making up four molecules for fertilized eggs, four marker molecules for first larvae (L1) and one marker molecule for third larvae (L3). Therefore, our findings indicate that this approach is suitable for biochemical characterization of A. lumbricoides development stages. Moreover, the straightforward analytical method employed, with almost no sample preparation from a complex matrix (feces) using high-resolution mass spectrometry, suggests that it is possible to seek for an easier and faster way to study animal molding processes.

  2. Image-based automatic recognition of larvae

    Science.gov (United States)

    Sang, Ru; Yu, Guiying; Fan, Weijun; Guo, Tiantai

    2010-08-01

    As the main objects, imagoes have been researched in quarantine pest recognition in these days. However, pests in their larval stage are latent, and the larvae spread abroad much easily with the circulation of agricultural and forest products. It is presented in this paper that, as the new research objects, larvae are recognized by means of machine vision, image processing and pattern recognition. More visional information is reserved and the recognition rate is improved as color image segmentation is applied to images of larvae. Along with the characteristics of affine invariance, perspective invariance and brightness invariance, scale invariant feature transform (SIFT) is adopted for the feature extraction. The neural network algorithm is utilized for pattern recognition, and the automatic identification of larvae images is successfully achieved with satisfactory results.

  3. Use of Probiotic Bacillus spp. in Rotifer (Brachionus plicatilis) and Artemia (Artemia urmiana) Enrichment: Effects on Growth and Survival of Pacific White Shrimp, Litopenaeus vannamei, Larvae.

    Science.gov (United States)

    Jamali, Hadi; Imani, Ahmad; Abdollahi, Daruosh; Roozbehfar, Reza; Isari, Amin

    2015-06-01

    This study was to evaluate the effect of a preparation of Bacillus probiotic (Bacillus licheniformis and B. subtilis, 1:1) on growth and survival rate of Pacific white shrimp, Litopenaeus vannamei larvae. The larvae were fed on Artemia urmiana nauplii and Brachionus plicatilis enriched with the probiotic preparation at 1 × 10(6) CFU mL(-1) rate. The experimental setup was completely randomized design comprised of six treatments, namely solo Artemia nauplii (A) or rotifer (R), Artemia nauplii and rotifer without any enrichment (A + R), Artemia nauplii enrichment with probiotic bacilli (Bacillus licheniformis and B. subtilis) (A + B), rotifer enrichment with probiotic bacilli (R + B) and enriched Artemia nauplii and rotifer (A + R + B). All treatments were performed in triplicate. Chemical parameters of rearing water viz. pH, salinity and temperature were 7.5-8, 30-31 ppt and 31-32 °C, respectively. Photoperiod was 16L:8D. Shrimp larvae were fed Artemia nauplii and rotifers at 5-20 and 10-40 individuals per shrimp larvae four times a day, respectively. Growth and survival rate of larvae were determined at MII, MIII, PL1, PL4, PL7 and PL10 stages. Larvae in A + R + B treatment showed the highest total length (10.89 ± 0.51 mm), weight (674 ± 73 μg) and survival rate (65% ± 3.5). Lowest total length, weight and survival rate (7.96 ± 0.63 mm, 493 ± 52 μg and 24.5 ± 2.4%, respectively) were recorded in treatment B larvae. We concluded that Bacillus probiotic can improve growth and survival rate of Pacific white shrimp larvae without conceivably undesirable effects.

  4. PODAAC-CYGNS-L1X20

    Data.gov (United States)

    National Aeronautics and Space Administration — This Level 1 (L1) dataset contains the Version 2.0 geo-located Delay Doppler Maps (DDMs) calibrated into Power Received (Watts) and Bistatic Radar Cross Section...

  5. Phobos L1 Operational Tether Experiment (PHLOTE)

    Data.gov (United States)

    National Aeronautics and Space Administration — A sensor package that “floats” just above the surface of Phobos, suspended by a tether from a small spacecraft operating at the Mars/Phobos Lagrange 1 (L1) Point...

  6. Predatory activity of Rhantus sikkimensis and larvae of Toxorhynchites splendens on mosquito larvae in Darjeeling, India.

    Science.gov (United States)

    Aditya, Gautam; Ash, Anirban; Saha, Goutam K

    2006-06-01

    Predation potential of the dytiscid beetle, Rhantus sikkimensis Regimbart 1899 and the larvae of Toxorhynchites splendens Wiedemann 1819 occurring along with the larval stages of the mosquitoes in the annual lentic water bodies of Darjeeling was evaluated using the larvae of Culex quinquefasciatus Say 1823 as preys, in the laboratory under simulated natural conditions. Field collected R. sikkimensis and larvae of Tx. splendens were offered IV instar larvae of Cx. quinquefasciatus to observe the rate of predation, at varying prey and predator densities. Based on the data obtained on the predation for a period of three consecutive days, two indices of predation, predatory impact (PI) and clearance rate (CR) values were estimated, and compared between the predator species. The rate of predation of IV instar Cx. quinquefasciatus larvae by R. sikkimensis ranged between 21.56 and 86.89 larvae per day, depending on the prey and predator densities. The PI value remained between 18.67 and 35.33 larvae/day depending on prey densities, while the CR ranged between 2.21 and 2.23 larvae litres/day/predator. Compared to these, the Tx. splendens larvae consumed the prey larvae at the rate of 0.67 to 34.22 larvae per day, depending on the prey and predator densities. The PI value ranged between 7.67 and 11.33 larvae/day, and the CR value ranged between 1.41 and 1.76 larvae litres/day/predator. The rate of predation, CR values and PI values of R. sikkimensis and Tx. splendens varied significantly. Both the predators R. sikkimensis and larvae of Tx. splendens can consume a good number of mosquito larvae, though the rate of consumption between the two predators vary owing to the difference in the life history traits and features. It can be assumed that these predators play an important role in larval population regulation of mosquitoes and thereby impart an effect on species composition and interactions in the aquatic insect communities of Darjeeling Hills, India.

  7. Momentum Strategies with L1 Filter

    OpenAIRE

    Dao, Tung-Lam

    2014-01-01

    In this article, we discuss various implementation of L1 filtering in order to detect some properties of noisy signals. This filter consists of using a L1 penalty condition in order to obtain the filtered signal composed by a set of straight trends or steps. This penalty condition, which determines the number of breaks, is implemented in a constrained least square problem and is represented by a regularization parameter ? which is estimated by a cross-validation procedure. Financial time seri...

  8. Growth performance and survival rate of Macrobrachium rosenbergii (De Man, 1979) larvae using different doses of probiotics.

    Science.gov (United States)

    Habib, Ahasan; Das, Nani Gopal; Hossain, M Belal

    2014-07-01

    The efficiency of probiotics (Ecomarine) in rearing of Macrobrachium rosenbergii larvae was evaluated in a commercial prawn hatchery for five weeks. Stage-1 (zero age) larvae (of length: 2 mm; weight: 0.12 mg) were stocked at the rate of 100 L(-1). The experiment determined the growth rate, survival rate of the larvae for the both treatment and control groups. Final average weight were found 8.39 ± 3.28E-04 and 8.18 ± 2.86E-04 mg and length were found 9.08 ± 0.649 and 9.02 ± 0.081 mm for treatment and control group respectively. Comparatively higher growth performance was observed in treatment than control. Post Larvae (PL) was first observed 20th days of culture in treatment tanks whereas PL in control tanks was found 24th days of culture. Survival rate was found 58 and 46% in treatment and control group respectively. There was significant (p < 0.05) survival rate between two experiment groups. This study revealed that probiotics could be better in quality seed production of M. rosenbergii while significant changes were not noticed in the physic-chemical parameters i.e., water temperature, salinity, DO, pH, nitrate-NO2, hardness and alkalinity observed in both the treatments.

  9. L1 arrest, daf-16/FoxO and nonautonomous control of post-embryonic development.

    Science.gov (United States)

    Kaplan, Rebecca E W; Baugh, L Ryan

    2016-01-01

    Post-embryonic development is governed by nutrient availability. L1 arrest, dauer formation and aging illustrate how starvation, anticipation of starvation and caloric restriction have profound influence on C. elegans development, respectively. Insulin-like signaling through the Forkhead box O transcription factor daf-16/FoxO regulates each of these processes. We recently reported that ins-4, ins-6 and daf-28 promote L1 development from the intestine and chemosensory neurons, similar to their role in dauer development. daf-16 functions cell-nonautonomously in regulation of L1 arrest, dauer development and aging. Discrepancies in daf-16 sites of action have been reported in each context, but the consensus implicates epidermis, intestine and nervous system. We suggest technical limitations of the experimental approach responsible for discrepant results. Steroid hormone signaling through daf-12/NHR is known to function downstream of daf-16 in control of dauer development, but signaling pathways mediating cell-nonautonomous effects of daf-16 in aging and L1 arrest had not been identified. We recently showed that daf-16 promotes L1 arrest by inhibiting daf-12/NHR and dbl-1/TGF-β Sma/Mab signaling, two pathways that promote L1 development in fed larvae. We will review these results on L1 arrest and speculate on why there are so many signals and signaling centers regulating post-embryonic development.

  10. Vitellin- and hemoglobin-digesting enzymes in Rhipicephalus (Boophilus) microplus larvae and females.

    Science.gov (United States)

    Estrela, Andréia Bergamo; Seixas, Adriana; Teixeira, Vivian de Oliveira Nunes; Pinto, Antônio Frederico Michel; Termignoni, Carlos

    2010-12-01

    The aim of the present study was to address the involvement of Rhipicephalus microplus larval cysteine endopeptidase (RmLCE) in protein digestion in R. microplus larvae and adult females. In this work, an improved purification protocol for native RmLCE was developed. Partial amino acid sequence of the purified enzyme indicates that it is the same enzyme as Boophilus microplus cathepsin-L1 (BmCL1). When vitellin (Vt) degradation by egg and larval enzymes was analyzed, stage-specific differences for RmLCE activity in comparison to vitellin-degrading cysteine endopeptidase (VTDCE) were observed. RmLCE is also able to degrade host hemoglobin (Hb). In agreement, an acidic cysteine endopeptidase activity was detected in larval gut. It was shown that cysteine and aspartic endopeptidases are involved in Vt and Hb digestion in R. microplus larvae and females. Interestingly, we observed that the aspartic endopeptidase Boophilus yolk cathepsin (BYC) is associated with a cysteine endopeptidase activity, in larvae. Synergic hemoglobin digestion by BYC and RmLCE was observed and indicates the presence of an Hb-degrading enzymatic cascade involving these enzymes. Our results suggest that RmLCE/BmCL1 has a continued role in vitellin and hemoglobin digestion during tick development. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Common European harmful algal blooms affect the viability and innate immune responses of Mytilus edulis larvae.

    Science.gov (United States)

    De Rijcke, M; Vandegehuchte, M B; Vanden Bussche, J; Nevejan, N; Vanhaecke, L; De Schamphelaere, K A C; Janssen, C R

    2015-11-01

    Like marine diseases, harmful algal blooms (HABs) are globally increasing in frequency, severity and geographical scale. As a result, bivalves will have to face the combined threat of toxic algae and marine pathogens more frequently in the (near) future. These stressors combined may further affect the recruitment of ecologically and economically important bivalve species as HABs can affect the growth, viability and development of their larvae. To date, little is known on the specific effects of HABs on the innate immune system of bivalve larvae. This study therefore investigates whether two common harmful algae can influence the larval viability, development and immunological resilience of the blue mussel Mytilus edulis. Embryos of this model organism were exposed (48 h) to five densities of Pseudo-nitzschia multiseries or Prorocentrum lima cells. In addition, the effect of six concentrations of their respective toxins: domoic acid (DA) and okadaic acid (OA) were assessed. OA was found to significantly reduce larval protein phosphatase activity (p lima (150 cells ml(-1)) and DA (dosed five times higher than typical environmental conditions i.e. 623.2 μg l(-1)) increased the phenoloxidase (PO) innate immune activity of the mussel larvae. These results suggest that the innate immune response of even the earliest life stages of bivalves is susceptible to the presence of HABs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Incidental Acquisition of Grammatical Features during Reading in L1 and L2

    Science.gov (United States)

    Bordag, Denisa; Kirschenbaum, Amit; Opitz, Andreas; Rogahn, Maria; Tschirner, Erwin

    2016-01-01

    The present study explores the initial stages of incidental acquisition of two grammatical properties of verbs (subcategorization and [ir]regularity) during reading in first language (L1) and second language (L2) German using an adjusted self-paced reading paradigm. The results indicate that L1 speakers are superior to L2 speakers in the…

  13. L1 influence in the L2 acquisition of isiXhosa verb placement by ...

    African Journals Online (AJOL)

    This paper reports on an investigation into the possibility of first language (L1) transfer in the initial stages of the second language (L2) acquisition of isiXhosa by adolescent L1 speakers of Afrikaans and English, respectively. Four hypotheses about the initial state of L2 acquisition are (i) the Full Transfer hypothesis ...

  14. Coral larvae move toward reef sounds.

    Directory of Open Access Journals (Sweden)

    Mark J A Vermeij

    Full Text Available Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm that influence settlement success are difficult to observe in situ and are therefore largely unknown. Here, we show that coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency.

  15. Validation of ATLAS L1 Topological Triggers

    CERN Document Server

    Praderio, Marco

    2017-01-01

    The Topological trigger (L1Topo) is a new component of the ATLAS L1 (Level-1) trigger. Its purpose is that of reducing the otherwise too high rate of data collection from the LHC by rejecting those events considered “uninteresting” (meaning that they have already been studied). This event rate reduction is achieved by applying topological requirements to the physical objects present in each event. It is very important to make sure that this trigger does not reject any “interesting” event. Therefore we need to verify its correct functioning. The goal of this summer student project is to study the response of two L1Topo algorithms (concerning ∆R and invariant mass). To do so I will compare the trigger decisions produced by the L1Topo hardware with the ones produced by the “official” L1Topo simulation. This way I will be able to identify events that could be incorrectly rejected. Simultaneously I will produce an emulation of these triggers that will help me understand the cause of disagreements bet...

  16. Nutrition and related ontogenetic aspects in larvae of the African catfish, Clarias gariepinus

    NARCIS (Netherlands)

    Verreth, J.

    1994-01-01


    The absence of adequate techniques for rearing fish larvae constitutes a bottleneck for sustainable aquacultural growth. Important constraints are the tiny size of the larvae, the dependance on live food organisms and the developmental stage of the fish larvae. The development

  17. Dirichlet expression for L(1, χ )

    Indian Academy of Sciences (India)

    We show that this expression with obvious modification is valid for the general primitive Dirichlet character χ. Keywords. Hurwitz zeta function; Dirichlet character; Dirichlet L-series; primitive character. 1. Introduction. In Dirichlet's famous work dealing with class number formula, the value of L(1,χ) is expressed in terms of finite ...

  18. Small Molecule Agonists of Cell Adhesion Molecule L1 Mimic L1 Functions In Vivo.

    Science.gov (United States)

    Kataria, Hardeep; Lutz, David; Chaudhary, Harshita; Schachner, Melitta; Loers, Gabriele

    2016-09-01

    Lack of permissive mechanisms and abundance of inhibitory molecules in the lesioned central nervous system of adult mammals contribute to the failure of functional recovery after injury, leading to severe disabilities in motor functions and pain. Peripheral nerve injury impairs motor, sensory, and autonomic functions, particularly in cases where nerve gaps are large and chronic nerve injury ensues. Previous studies have indicated that the neural cell adhesion molecule L1 constitutes a viable target to promote regeneration after acute injury. We screened libraries of known drugs for small molecule agonists of L1 and evaluated the effect of hit compounds in cell-based assays in vitro and in mice after femoral nerve and spinal cord injuries in vivo. We identified eight small molecule L1 agonists and showed in cell-based assays that they stimulate neuronal survival, neuronal migration, and neurite outgrowth and enhance Schwann cell proliferation and migration and myelination of neurons in an L1-dependent manner. In a femoral nerve injury mouse model, enhanced functional regeneration and remyelination after application of the L1 agonists were observed. In a spinal cord injury mouse model, L1 agonists improved recovery of motor functions, being paralleled by enhanced remyelination, neuronal survival, and monoaminergic innervation, reduced astrogliosis, and activation of microglia. Together, these findings suggest that application of small organic compounds that bind to L1 and stimulate the beneficial homophilic L1 functions may prove to be a valuable addition to treatments of nervous system injuries.

  19. Inclusion of copepod Acartia tonsa nauplii in the feeding of Centropomus undecimalis larvae increases stress resistance

    Directory of Open Access Journals (Sweden)

    Wanessa de Melo-Costa

    2015-09-01

    Full Text Available This research represents the first result of studies of the common snook Centropomus undecimalis larvae from broodstock matured in captivity in Brazil. The aim of this study was to evaluate if the inclusion of Acartia tonsa nauplii improves stress resistance of common snook larvae. The larvae were fed with: rotifers Brachionus plicatilis (10 to 15 mL-1; A. tonsa nauplii (0.25 to 0.5 mL-1 and rotifers (5 to 7.5 mL-1, and A. tonsa nauplii (0.12 to 0.25 mL-1. The average percentage of survival of the treatments was 11.9%. At 20 days of age, larvae were subjected to thermal stress. Subsequently, the stress resistance was evaluated. Common snook larvae fed B. plicatilis+A. tonsa reached a higher weight and length (7.5 ± 0.00 mg and 9.1 ± 0.23 mm, respectively and resisted more heat stress (87.4% than larvae fed other foods, indicating that the feed mixture is satisfactory as a starter diet for larvae of common snook. However, more research is needed to confirm these results.

  20. Comparison of constitutive and thiabendazole-induced expression of five cytochrome P450 genes in fourth-stage larvae of Haemonchus contortus isolates with different drug susceptibility identifies one gene with high constitutive expression in a multi-resistant isolate.

    Science.gov (United States)

    Yilmaz, Esra; Ramünke, Sabrina; Demeler, Janina; Krücken, Jürgen

    2017-12-01

    Benzimidazoles (BZs) remain amongst the most widely used anthelmintic drug classes against gastro-intestinal nematode infections, although their efficacy is increasingly compromised by resistance. The primary underlying mechanisms for BZ resistance are single-nucleotide polymorphisms (SNPs) in the isotype 1 β-tubulin gene causing the substitutions F167Y, E198A or F200Y. However, resistance is believed to be multi-genic and previous studies have shown that isolates carrying 90-100% F200Y can vary considerably in their resistance level in the egg hatch assay (EHA). Cytochrome P450 monooxygenases (CYPs) are associated with drug resistance in mammals and arthropods and have been considered as mediators of anthelmintic resistance. In Caenorhabditis elegans, several members of the CYP34/35 and CYP31 families are BZ and/or xenobiotic inducible and thiabendazole (TBZ) is metabolised by CYP35D1. Here, expression of all 5 CYPs closely related to the C. elegans CYP34/35 and CYP31 families was investigated in fourth-stage larvae of two susceptible and three BZ-resistant Haemonchus contortus isolates following in vitro exposure to TBZ for 3 and 6 h using real-time RT-PCR. The resistance status of all isolates was determined using EHAs and quantification of resistance-associated β-tubulin SNPs using pyrosequencing. While none of the CYPs was TBZ inducible, constitutive expression of CYP34/35 family member HCOI100383400 was significantly 2.4-3.7-fold higher in the multi-drug resistant WR isolate with the strongest BZ resistance phenotype compared to susceptible and intermediate-level BZ-resistant isolates. Although this increase is only moderate, HCOI100383400 might still be involved in high-level BZ resistance by further decreasing susceptibility in isolates already carrying 100% of a β-tubulin SNP causing BZ resistance. Lower transcript levels were observed for all CYPs in the intermediately resistant IRE isolate in comparison to the susceptible HcH isolate, which, except

  1. Dirichlet expression for L(1, χ )

    Indian Academy of Sciences (India)

    log sin πa d. , if d > 0. Here L(s,χ) is the Dirichlet's L-series associated with the real primitive charac- ter (d/a), where (d/a) is Kronecker's symbol. The question arises as to whether the corresponding expression for L(1,χ) holds for any general primitive Dirichlet character χ(mod q), where q ≥ 2 is an integer. We shall show ...

  2. On weak compactness in L_1 spaces

    Czech Academy of Sciences Publication Activity Database

    Fabian, Marián; Montesinos, V.; Zizler, Václav

    2009-01-01

    Roč. 39, č. 6 (2009), s. 1885-1893 ISSN 0035-7596 R&D Projects: GA AV ČR(CZ) IAA100190610; GA AV ČR IAA100190502; GA AV ČR IAA1019103 Institutional research plan: CEZ:AV0Z10190503 Keywords : weak compactness * subspace of L_1 * superreflexive space Subject RIV: BA - General Mathematics Impact factor: 0.260, year: 2009

  3. Baylisascaris Larva Migrans

    Science.gov (United States)

    Kazacos, Kevin R.; Abbott, Rachel C.; van Riper, Charles

    2016-05-26

    SummaryBaylisascaris procyonis, the common raccoon roundworm, is the most commonly recognized cause of clinical larva migrans (LM) in animals, a condition in which an immature parasitic worm or larva migrates in a host animal’s tissues, causing obvious disease. Infection with B. procyonis is best known as a cause of fatal or severe neurologic disease that results when the larvae invade the brain, the spinal cord, or both; this condition is known as neural larva migrans (NLM). Baylisascariasis is a zoonotic disease, that is, one that is transmissible from animals to humans. In humans, B. procyonis can cause damaging visceral (VLM), ocular (OLM), and neural larva migrans. Due to the ubiquity of infected raccoons around humans, there is considerable human exposure and risk of infection with this parasite. The remarkable disease-producing capability of B. procyonis in animals and humans is one of the most significant aspects of the biology of ascarids (large roundworms) to come to light in recent years. Infection with B. procyonis has important health implications for a wide variety of free-ranging and captive wildlife, zoo animals, domestic animals, as well as human beings, on both an individual and population level. This report, eighth in the series of U.S. Geological Survey Circulars on zoonotic diseases, will help us to better understand the routes of Baylisascaris procyonis infections and how best to adequately monitor this zoonotic disease.

  4. The influence of dietary concentrations of arachidonic acid and eicosapentaenoic acid at various stages of larval ontogeny on eye migration, pigmentation and prostaglandin content of common sole larvae ( Solea solea L.)

    DEFF Research Database (Denmark)

    Lund, Ivar; Steenfeldt, Svend Jørgen; Banta, G.

    2008-01-01

    metamorphosis. Initiation of metamorphosis (i.e. start of eye migration) was related to the size of larvae and not related to ARA or EPA content. Dietary EPA or DHA did not retard the advance of eye migration. More than 90 % of highly malpigmented juveniles, (i.e. "albinos") had a permanent aberrant eye...

  5. Evaluation of the Toxic Effect from Eupatorium Microphyllum L.F. (Asteraceae Extracts on Aedes Aegypti Larvae (Diptera: Culicidae in Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Álvaro Rozo

    2008-07-01

    Full Text Available In the present work the toxic activity ofextracts of Eupatorium microphyllum L.F. wasevaluated on 4th instar larvae of the mosquitoAedes aegypti (Linneaus, under laboratoryconditions. Aqueous extracts were utilized inconcentrations of 500 mg L-1, 1,500 mg L-1 and2,500 mg L-1 and acetone in concentrations of10 mg L-1, 20 mg L-1, 30 mg L-1, 40 mg L-1and50 mg L-1. The bioassays were carried out fortriplicate each one with 20 larvae, exposedfor 24 hours to 150 mL of solution. In all thebioassays were employed control groups. Inthe evaluation of the acetone extracts, a negativecontrol was employed to avoid that themortality of the larvae to occur on account ofthe solvent. The Aqueous extracts showed lowmoderate action in the mortality of larvae, lessthan 20%. On the contrary, the action of theacetone extracts was observed to 10 and 20 mgL-1with 15% of mortality, while to 30 and 40mg L-1 were registered 22 to 38% of mortality.However, to 50 mg L-1 the mortality wasof 95.4% with highly significant statisticalresults. The concentrations of the acetone extractsshowed to be the most efficient for thecontrol of the mosquitoes selected. Both typesof extracts showed toxic effect in larvae of A.aegypti, nevertheless, greater effect in theacetone extracts was observed relating to theaqueous extracts of E. microphyllum, whichconstitutes a viable alternative in the search ofnew larvicides from composed natural.

  6. Three cases with L1 syndrome and two novel mutations in the L1CAM gene.

    Science.gov (United States)

    Marín, Rosario; Ley-Martos, Miriam; Gutiérrez, Gema; Rodríguez-Sánchez, Felicidad; Arroyo, Diego; Mora-López, Francisco

    2015-11-01

    Mutations in the L1CAM gene have been identified in the following various X-linked neurological disorders: congenital hydrocephalus; mental retardation, aphasia, shuffling gait, and adducted thumbs (MASA) syndrome; spastic paraplegia; and agenesis of the corpus callosum. These conditions are currently considered different phenotypes of a single entity known as L1 syndrome. We present three families with L1 syndrome. Sequencing of the L1CAM gene allowed the identification of the following mutations involved: a known splicing mutation (c.3531-12G>A) and two novel ones: a missense mutation (c.1754A>C; p.Asp585Ala) and a nonsense mutation (c.3478C>T; p.Gln1160Stop). The number of affected males and carrier females identified in a relatively small population suggests that L1 syndrome may be under-diagnosed. L1 syndrome should be considered in the differential diagnosis of intellectual disability or mental retardation in children, especially when other signs such as hydrocephalus or adducted thumbs are present.

  7. Feeding behaviour of snake head fish, Channa striatus larvae

    Directory of Open Access Journals (Sweden)

    Thumronk Amornsakun1*

    2011-12-01

    Full Text Available Feeding scheme experiments were done in a 15-liter glass aquarium (water volume 10 liters containing 500 of two-dayold larvae (stage at first feeding. It was found that larval snake head fish aged 3-11 days (average total length 6.08-10.86 mmconsumed Moina. Larvae aged 12-15 days (average total length 10.79-14.61 mm consumed both Moina and commercialpellet (40 % crude protein. Larvae aged more than 16 days consumed only commercial pellet.Determining the daily food uptake by the larvae and juveniles was done in a 15-liter glass aquarium (water volume 10liters containing 1,000 larvae. The larvae consumed Moina ,provide of a density of Moina 10 individual/ml. The amount offood intake was calculated based on changes of food density in the aquarium with and without fish larvae at 2-hour intervals.It was found that larvae aged 3-15 days consumed Moina. The average uptake of Moina in digestive tract per day of larvaeage 3, 6, 9, 12 and 15 days old was 28.7, 115.70, 162.27, 195.30 and 227.30 individual/larva, respectively at water temperaturesranging between 25 and 28°C.A starvation experiment was carried out using a 15-liter glass aquarium (water volume 10 liters with three replications.Two hundred newly hatched larvae were kept without feeding. Larvae started to die at 216 hr and totally died within 326 hrafter hatching at water temperature ranging between 28.0 and 30.5°C.

  8. Análise da dieta das larvas de 4º estádio de Cricotopus sp. (Diptera: Chironomidae, em diferentes substratos artificiais e fases hídricas, no trecho superior do rio Paraná = Diet analysis of Cricotopus sp. larvae (Diptera: Chironomidae, fourth stage, in different artificial substrates and hydrological phases, in the upper Paraná river

    Directory of Open Access Journals (Sweden)

    Adriana Felix dos Anjos

    2009-10-01

    Full Text Available No Brasil, estudos sobre hábitos alimentares das larvas de Chironomidae ainda são escassos e estas informações são importantes para entender a estrutura trófica e a organização dos ecossistemas aquáticos. Neste estudo, teve-se como objetivo identificar osprincipais itens alimentares ingeridos por Cricotopus sp. e comparar as possíveis diferenças na dieta das larvas em diferentes substratos artificiais e fases hídricas. Foram utilizados quatro tipos de substratos artificiais: madeira em forma de X (MADX, placas de nitacetal em forma de X (NITX, PVC em forma de tubo (PVCT e metal galvanizado em forma de tubo (METT, cada um com três réplicas. As coletas foram realizadas quinzenalmente, entre os meses de agosto de 2004 e dezembro de 2005. A dieta de Cricotopus sp. foi constituída por detritos, algas e hifas de fungos. Detrito foi o principal item alimentar, com valores superiores a 50% do total consumido. Os resultados indicaram que Cricotopus sp. é uma espécie coletora e, independentemente do substrato, as larvas alimentam-se dos recursos disponíveis no ambiente. Entretanto, mudanças no regime hidrológico do rio Paraná podem influenciar a disponibilidade de alimento, principalmente algumas diatomaceas como Melosira sp., consumidas em maior quantidade apenas na fase de águas baixas.In Brazil, studies on the diet of Chironomidae larvae are still scarce and these data are important to understand the trophic structure and organization of aquatic ecosystems. In this study, we identified the main food items consumed by Cricotopus sp. and compared possible differences in the larval diet at different artificial substrates and hydrological phases. We used four types of artificial substrates: X-shaped wood (MADX; X-shaped nitacetal plates (NITX; tube-shaped PVC (PVCT and tube-shaped galvanizedmetal (METT, each with three replicates. Samplings were undertaken fortnightly, between August 2004 and December 2005. Cricotopus sp. diet was

  9. Interpretation of Secondary Predicates by L1 and L2 Acquisition of Japanese

    OpenAIRE

    Suzuki, Sayaka

    2004-01-01

    This study reports the experimental data dealing with differences of the acquisition sequence of Japanese secondary depictive predicates and affectedness of Japanese verbs between Japanese speaking young children (L1 acquisition) and Mandarin Chinese speaking adults learning Japanese (L2 acquisition). The results support Schwartz and Sprouse’s (1996) and Eubank’s (1996) hypothesis that L2 grammar is derived from learners’ L1 grammar at an early stage of L2 acquisition.

  10. Protein Metabolism in Lecithotrophic Larvae (Gastropoda: Haliotis rufescens).

    Science.gov (United States)

    Vavra, J; Manahan, D T

    1999-04-01

    Rates of protein depletion, synthesis, and turnover were measured in larvae of the abalone Haliotis rufescens as an approach to understanding macromolecular metabolism during lecithotrophic development. Protein content decreased linearly during development to metamorphic competence, with 34% of the initial protein in eggs depleted during the 8-day larval life span. Fractional rates of protein synthesis (percentage of total body-protein synthesized per day) decreased during development, from 40% (1-day-old trochophore larva) to 14% (7-day-old veliger larva). Separation of proteins by one-dimensional gel electrophoresis showed that protein pools in larvae are dominated by two high-molecular-weight protein classes (88 and 121 kDa). When the proteins of 1- and 3-day-old larvae were labeled with a mixture of 35S-methionine and cysteine, the pattern on two-dimensional gels showed that the turnover process (protein synthesis and degradation) involved hundreds of different proteins. The energy gained from loss of protein could account for 20% of the protein turnover rates for trochophore larvae and 79% of the lower turnover costs for late-stage veligers. Lecithotrophic larvae of H. rufescens maintained high biosynthetic activities, with up to 40% of their whole-body protein being turned over each day. Such dynamic processes during development of nonfeeding larvae would contribute significantly to maintenance metabolism.

  11. Seasonality of larvae of Brachyura and Anomura (Crustacea Decapoda in the Beagle Channel, Argentina

    Directory of Open Access Journals (Sweden)

    Gustavo A. Lovrich

    1999-12-01

    Full Text Available This is the first study in the Beagle Channel that reports the larval seasonal distribution, abundance and duration of the larval stages of Anomura and Brachyura, on the basis of a fortnightly sampling programme. An identification key to the specific level of zoeal stages is included. Between September 1987 and March 1989, 304 plankton samples were taken by means of oblique hauls from the bottom to the sea-surface. Eighty-five percent of the samples were taken shallower than 60 m depth. Decapod larvae occurred only in spring and summer. All but two taxa showed a single cohort of larvae which emerge at the beginning of the spring. A second cohort of Munida spp. and Halicarcinus planatus also occurred during summer. The most abundant taxa were Munida spp. (312 larvae ? 10 m-3, Peltarion spinosulum (288 larvae ? 10 m-3,, H. planatus (143 larvae ? 10 m-3, and Pagurus spp. (79 larvae ? 10 m-3, which represented 97% of the total larvae collected. Larvae of Pinnotheridae, Eurypodius latreillii, Libidoclaea granaria, and Paralomis granulosa were about an order of magnitude less abundant. Relative abundances of larvae correspond to relative abundances of the respective benthic stages. The absence of certain larval stages or of certain species (Acanthocyclus albatrossis and Lithodes santolla probably indicates their differential distribution within the Beagle Channel. Particularly, lithodid larvae may have benthic or epibenthic habits.

  12. Contribution of L1 in EFL Teaching

    Directory of Open Access Journals (Sweden)

    Wahjuningsih Usadiati

    2009-01-01

    Full Text Available This study is conducted in a classroom action research to improve the students’ achievement in writing English sentences in Present Perfect Tense in Structure 1 lessons. The subject consisted of 20 Semester II students who took Structure I lessons in English Education Department of Palangka Raya University, Central Kalimantan, Indonesia. The data were taken from the results of pre test and post test after the action was done. The results show that in cycle 1, in which the explanations were fully in English, only 40% of the students got a good achievement; 5-7 out of 20 test items were correct. After cycle 2 was done using L1 interchangeably with English in the explanations, the students’ achievement of writing English sentences in Present Perfect Tense increased to 75%, in which 15-18 out 20 test items were correct.

  13. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Aladawi, M.A. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic)]. E-mail: Scientific@aec.org.sy; Albarodi, H. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Hammoudeh, A. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Shamma, M. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic); Sharabi, N. [Syrian Atomic Energy Commission, Radiation Technology Department, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2006-01-15

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented.

  14. Accelerated larvae development of Ascaris lumbricoides eggs with ultraviolet radiation

    Science.gov (United States)

    Aladawi, M. A.; Albarodi, H.; Hammoudeh, A.; Shamma, M.; Sharabi, N.

    2006-01-01

    In order to investigate the effect of UV radiation on the development of Ascaris lumbricoides larvae, eggs were exposed to increasing UV doses. Filtered wastewater from the secondary effluent taken from the Damascus wastewater treatment plant (DWTP) was used as irradiation and incubation medium. The progressive and accelerated embryonation stages were microscopically observed and the percentages of completely developed larvae were determined weekly. Results indicated that the UV radiation accelerated the development of larvae with increasing UV dose. Preliminary information about the relationship between the UV radiation dose and rate of embryonation is also presented.

  15. Efeito da composição iônica da água do mar artificial no desenvolvimento de larvas de Macrobrachium rosenbergii - DOI: 10.4025/actascibiolsci.v20i0.4484 Effect of artificial seawater ionic composition on the development of Macrobrachium rosenbergii (De Man, 1879 [Crustacea, Decapoda] at the larval stage II - DOI: 10.4025/actascibiolsci.v20i0.4484

    Directory of Open Access Journals (Sweden)

    Margarete Mallasen

    1998-07-01

    Full Text Available Avaliou-se a importância da presença na água dos íons Ca2+, K+, HCO3-, Br-, Sr2+, Mn2+, HPO42-, Li+, MoO42-, S2O32-, Al3+, Rb+, Zn2+, Co2+ e Cu2+ para o desenvolvimento do Macrobrachium rosenbergii no estágio larval II. Aplicou-se um teste de inanição, que consistiu na estocagem das larvas em béqueres contendo 15ml de água salobra (12‰, de diferentes composições iônicas. A cada 8 horas contou-se o número de larvas vivas e calculou-se o tempo médio de vida em todos os tratamentos. Os elementos Al3+, Rb+, Zn2+, Co2+, Cu2+, Sr2+, Mn2+, HPO42-, Li+, MoO42- e S2O32- não influenciaram o tempo de vida das larvas. O K+ e o Ca2+ foram os íons mais importantes para o desenvolvimento das larvas, seguidos pelo Br- e pelo HCO3-, respectivamente, a presença desses íons no meio é indispensável e as larvas devem apresentar mecanismos eficientes de absorção desses elementos.The importance of the ions Ca2+, K+, HCO3-, Br-, Sr2+, Mn2+, HPO42-, Li+, MoO42-, S2O32-, Al3+, Rb+, Zn2+, Co2+ and Cu2+ in water on the development of Macrobrachium rosenbergii at the larval stage II was evaluated. A starvation test was applied. It consisted in keeping larvae of M. rosenbergii in beakers containing 15ml of brackish water (12‰ with different ionic compositions. In order to estimate average life time, larvae which survived the treatment were counted every eight hours. Elements Al3+, Rb+, Zn2+, Co2+,Cu2+, Sr2+, Mn2+, HPO42-, Li+, MoO4M2- and S2O32 were not effective on the larvae life time, whereas K and Ca2+ were the most important ions for larvae development, followed by Br- and HCO3-, respectively. These ions are indispensable in water and larvae must have an efficient mechanism to absorb them.

  16. Analysis list: Tcf7l1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Tcf7l1 Embryonic fibroblast + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Tcf7...l1.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Tcf7l1.5.tsv http://dbarchive.biosci...encedbc.jp/kyushu-u/mm9/target/Tcf7l1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Tcf7l1.Embr

  17. Permeation and toxicity of ethylene glycol and methanol in larvae of Anopheles gambiae.

    Science.gov (United States)

    Liu, Xiang-Hong; Pan, Hongjun; Mazur, Peter

    2003-07-01

    In this study, we applied proton NMR to measure the permeation of two cryoprotective agents (CPAs), ethylene glycol (EG) and methanol, into 1st instar Anopheles larvae. Calibration with standard solutions of EG or methanol (0-10 mol l(-1)) confirmed the reliability of the NMR measurements for determining the concentration of these solutes. To assess permeation, larvae were immersed in 1.5 mol l(-1) EG or 1.5 mol l(-1) methanol for different periods of time at 22 degrees C. The concentration of both CPAs in the larvae was then measured as a function of exposure time using (1)H-NMR spectroscopy. Results show that after a 6 h exposure to 1.5 mol l(-1) EG, the larval concentration of EG reaches a maximum value of 1.44 mol l(-1), which is 96% of the theoretical maximum. By contrast, after just 1 h exposure to 1.5 mol l(-1) methanol, the larval methanol concentration reaches its maximum, which, however, is only 75% of the theoretical maximum. Toxicity data show that larval survival remains 91% and 95% after 4 h and 1 h exposure to 1.5 mol l(-1) EG and 1.5 mol l(-1) methanol, respectively, at which time the larval concentration of EG and methanol has risen to 1.21 mol l (-1) and 1.13 mol l(-1), respectively. These results suggest that CPAs such as EG and methanol do permeate Anopheles larvae to up to 81% and 75% of equilibrium, respectively, before the exposure becomes toxic.

  18. Evolution of foraging behavior in Drosophilid larvae

    Science.gov (United States)

    Rivera-Alba, Marta; Kabra, Mayank; Branson, Kristin; Mirth, Christen

    2015-03-01

    Drosophilids, like other insects, go through a larval phase before metamorphosing into adults. Larvae increase their body weight by several orders of magnitude in a few days. We therefore hypothesized that foraging behavior is under strong evolutionary pressure to best fit the larval environment. To test our hypothesis we used a multidisciplinary approach to analyze foraging behavior across species and larval stages. First, we recorded several videos of larvae foraging for each of 47 Drosophilid species. Then, using a supervised machine learning approach, we automatically annotated the video collection for the foraging sub-behaviors, including crawling, turning, head casting or burrowing. We also computed over 100 features to describe the posture and dynamics of each animal in each video frame. From these data, we fit models to the behavior of each species. The models each had the same parametric form, but differed in the exact parameters. By simulating larva behavior in virtual arenas we can infer which properties of the environments are better for each species. Comparisons between these inferred environments and the actual environments where these animals live will give us a deeper understanding about the evolution of foraging behavior in Drosophilid larvae.

  19. Increase of cells expressing PD-L1 in bovine leukemia virus infection and enhancement of anti-viral immune responses in vitro via PD-L1 blockade

    Directory of Open Access Journals (Sweden)

    Ikebuchi Ryoyo

    2011-09-01

    Full Text Available Abstract The inhibitory receptor programmed death-1 (PD-1 and its ligand, programmed death-ligand 1 (PD-L1 are involved in immune evasion mechanisms for several pathogens causing chronic infections. Blockade of the PD-1/PD-L1 pathway restores anti-virus immune responses, with concomitant reduction in viral load. In a previous report, we showed that, in bovine leukemia virus (BLV infection, the expression of bovine PD-1 is closely associated with disease progression. However, the functions of bovine PD-L1 are still unknown. To investigate the role of PD-L1 in BLV infection, we identified the bovine PD-L1 gene, and examined PD-L1 expression in BLV-infected cattle in comparison with uninfected cattle. The deduced amino acid sequence of bovine PD-L1 shows high homology to the human and mouse PD-L1. The proportion of PD-L1 positive cells, especially among B cells, was upregulated in cattle with the late stage of the disease compared to cattle at the aleukemic infection stage or uninfected cattle. The proportion of PD-L1 positive cells correlated positively with prediction markers for the progression of the disease such as leukocyte number, virus load and virus titer whilst on the contrary, it inversely correlated with the degree of interferon-gamma expression. Blockade of the PD-1/PD-L1 pathway in vitro by PD-L1-specific antibody upregulated the production of interleukin-2 and interferon-gamma, and correspondingly, downregulated the BLV provirus load and the proportion of BLV-gp51 expressing cells. These data suggest that PD-L1 induces immunoinhibition in disease progressed cattle during chronic BLV infection. Therefore, PD-L1 would be a potential target for developing immunotherapies against BLV infection.

  20. Feeding rates of the jellyfish Aurelia aurita on fish larvae

    DEFF Research Database (Denmark)

    Titelman, J.; Hansson, L.J.

    2006-01-01

    We quantified feeding rates of field caught Aurelia aurita feeding on yolk sac cod (Gadus morhua) larvae in a series of incubation experiments. A short-time (similar to 1 h) functional response experiment with a wide range of prey concentrations (0.5-16 prey l(-1)supercript stop, initial concentr......We quantified feeding rates of field caught Aurelia aurita feeding on yolk sac cod (Gadus morhua) larvae in a series of incubation experiments. A short-time (similar to 1 h) functional response experiment with a wide range of prey concentrations (0.5-16 prey l(-1)supercript stop, initial...... of prey captured by A. aurita during 2.5 h of feeding at extremely high prey concentration (> 200 prey l(-1)). Clearance rate in darkness scaled with jellyfish diameter to a power of similar to 1.7 for jellyfish 3.9-9.5 cm in diameter. The jellyfish did not alter their umbrella pulse frequency in response...... to presence of fish larvae. There were no significant differences between A. aurita feeding rates in light and darkness for yolk sac prey ages 0-7 days (at 7.5 degrees C). Although prey vision and escape abilities of fish may develop rapidly during early larval ontogeny, these factors apparently have little...

  1. The Role of Somatic L1 Retrotransposition in Human Cancers

    OpenAIRE

    Scott, Emma C.; Devine, Scott E.

    2017-01-01

    The human LINE-1 (or L1) element is a non-LTR retrotransposon that is mobilized through an RNA intermediate by an L1-encoded reverse transcriptase and other L1-encoded proteins. L1 elements remain actively mobile today and continue to mutagenize human genomes. Importantly, when new insertions disrupt gene function, they can cause diseases. Historically, L1s were thought to be active in the germline but silenced in adult somatic tissues. However, recent studies now show that L1 is active in at...

  2. Lagrangian Observations and Modeling of Marine Larvae

    Science.gov (United States)

    Paris, Claire B.; Irisson, Jean-Olivier

    2017-04-01

    Just within the past two decades, studies on the early-life history stages of marine organisms have led to new paradigms in population dynamics. Unlike passive plant seeds that are transported by the wind or by animals, marine larvae have motor and sensory capabilities. As a result, marine larvae have a tremendous capacity to actively influence their dispersal. This is continuously revealed as we develop new techniques to observe larvae in their natural environment and begin to understand their ability to detect cues throughout ontogeny, process the information, and use it to ride ocean currents and navigate their way back home, or to a place like home. We present innovative in situ and numerical modeling approaches developed to understand the underlying mechanisms of larval transport in the ocean. We describe a novel concept of a Lagrangian platform, the Drifting In Situ Chamber (DISC), designed to observe and quantify complex larval behaviors and their interactions with the pelagic environment. We give a brief history of larval ecology research with the DISC, showing that swimming is directional in most species, guided by cues as diverse as the position of the sun or the underwater soundscape, and even that (unlike humans!) larvae orient better and swim faster when moving as a group. The observed Lagrangian behavior of individual larvae are directly implemented in the Connectivity Modeling System (CMS), an open source Lagrangian tracking application. Simulations help demonstrate the impact that larval behavior has compared to passive Lagrangian trajectories. These methodologies are already the base of exciting findings and are promising tools for documenting and simulating the behavior of other small pelagic organisms, forecasting their migration in a changing ocean.

  3. The Role of Somatic L1 Retrotransposition in Human Cancers.

    Science.gov (United States)

    Scott, Emma C; Devine, Scott E

    2017-05-31

    The human LINE-1 (or L1) element is a non-LTR retrotransposon that is mobilized through an RNA intermediate by an L1-encoded reverse transcriptase and other L1-encoded proteins. L1 elements remain actively mobile today and continue to mutagenize human genomes. Importantly, when new insertions disrupt gene function, they can cause diseases. Historically, L1s were thought to be active in the germline but silenced in adult somatic tissues. However, recent studies now show that L1 is active in at least some somatic tissues, including epithelial cancers. In this review, we provide an overview of these recent developments, and examine evidence that somatic L1 retrotransposition can initiate and drive tumorigenesis in humans. Recent studies have: (i) cataloged somatic L1 activity in many epithelial tumor types; (ii) identified specific full-length L1 source elements that give rise to somatic L1 insertions; and (iii) determined that L1 promoter hypomethylation likely plays an early role in the derepression of L1s in somatic tissues. A central challenge moving forward is to determine the extent to which L1 driver mutations can promote tumor initiation, evolution, and metastasis in humans.

  4. The Role of Somatic L1 Retrotransposition in Human Cancers

    Directory of Open Access Journals (Sweden)

    Emma C. Scott

    2017-05-01

    Full Text Available The human LINE-1 (or L1 element is a non-LTR retrotransposon that is mobilized through an RNA intermediate by an L1-encoded reverse transcriptase and other L1-encoded proteins. L1 elements remain actively mobile today and continue to mutagenize human genomes. Importantly, when new insertions disrupt gene function, they can cause diseases. Historically, L1s were thought to be active in the germline but silenced in adult somatic tissues. However, recent studies now show that L1 is active in at least some somatic tissues, including epithelial cancers. In this review, we provide an overview of these recent developments, and examine evidence that somatic L1 retrotransposition can initiate and drive tumorigenesis in humans. Recent studies have: (i cataloged somatic L1 activity in many epithelial tumor types; (ii identified specific full-length L1 source elements that give rise to somatic L1 insertions; and (iii determined that L1 promoter hypomethylation likely plays an early role in the derepression of L1s in somatic tissues. A central challenge moving forward is to determine the extent to which L1 driver mutations can promote tumor initiation, evolution, and metastasis in humans.

  5. Tadpoles of three common anuran species from Thailand do not prey on mosquito larvae.

    Science.gov (United States)

    Weterings, Robbie

    2015-12-01

    Tadpoles are often considered to be predators of mosquito larvae and are therefore beneficial for the control of certain disease vectors. Nevertheless, only a few species have actually been recorded to prey on mosquito larvae. The mosquito larvae predation rates of tadpoles of three common Thai anuran species (Bufo melanostictus, Kaloula pulchra and Hylarana raniceps) were experimentally tested. Tadpoles in varying developmental stages were used to assess a size/age effect on the predation rate. In addition, different instars of Culex quinquefasciatus were used in order to assess a prey size effect on the predation rates. All three species failed to show any evidence of mosquito larvae predation. Neither small nor large tadpoles fed on mosquito larvae. Prey size also did not affect predation. Although tadpoles do not feed on mosquito larvae, there may be other direct or indirect inter-specific interactions that adversely impact the development of larvae in shared habitats with tadpoles. © 2015 The Society for Vector Ecology.

  6. Berbagai Cara Pengendalian Larva Nyamuk

    Directory of Open Access Journals (Sweden)

    Nungki Hapsari Suryaningtyas

    2017-02-01

    Full Text Available Tindakan pencegahan dengan memberantas sarang nyamuk dan membunuh larva serta nyamuk dewasa terus digalakkan. Stadium pradewasa atau larva dapat dikontrol secara biologi maupun kimiawi.1 Berikut adalah beberapa cara pengendalian larva nyamuk.Pengendalian secara biologi Beberapa organisme yang efektif untuk mengendalikan larva secara biologi diantaranya adalah Ikan (larvavivorous fish,Aplocheilus panchax (ikan kepala timah, Ctenops vittatus (ikan cupang,Oreochromis (Tilapia mossambicus (ikan nila dan Cyprinus carpio (ikan tombro, larva nyamuk dari genus Toxorhynchites, Capung (Dragonflies/Labellula . Kelompok Udang (Cyclopoid copepods Jenis Copepoda yang tersebar sebagai plankton dan bentos ini bersifat predator yang efektif untuk mengendalikan stadium pradewasa nyamuk instar satu dan instar dua. Pada suatu penelitian di Polynesia Perancis terbukti bahwa M. aspericornis pengaruhnya tidak konsisten terhadap larva Ae. aegypti yang ditemukan berada di tangki air, drum dan sumur yang tertutup. Keadaan tersebut tampaknya bergantung pada tersedianya mikrofauna di tempat perkembangbiakannya yang dibutuhkan untuk pertumbuhan Copepoda tersebut

  7. Effects of copper on the physiological responses of the commercial crab Lithodes santolla (Decapoda: Anomura larvae

    Directory of Open Access Journals (Sweden)

    Oscar Antonio Amin

    2010-06-01

    Full Text Available Effects of copper toxicity on zoea I of Lithodes santolla (Decapoda: Anomura were analysed. The 96-h LC50 was estimated, resulting in 298.5 µg L-1. Groups of larvae were exposed to sublethal concentrations (40, 80 and 160 µg L-1 for 96 h. Oxygen consumption, ammonia excretion, O:N atomic ratio, lipid peroxidation (LPO and body water content were measured. Oxygen consumption of treated groups (mean 46.92 ± 8.03 µg-atom O2 h-1 mg-1 did not differ significantly with control. Ammonia excretion decreased by 60% at higher Cu concentration (1.61 ± 0.65 µg-atom N-NH3 h-1 mg-1, leading to a 117% increase in the O:N ratio. LPO values during the exposure time were higher in all treatments than in the controls. The water content was significantly higher in treatments than in controls. The highest concentration assayed, which represents about 50% of 96-h LC50, had evident effects on the parameters analysed. The values of copper in water reported for the coastal zone of Ushuaia bay exceed the value established by the United States Environmental Protection Agency (USEPA for ambient water quality criteria. Therefore, the results obtained in the present study are a contribution to the study of potential effects of copper as a common stressor in the first larval stage of this commercial species of the Beagle Channel.

  8. Caracterização dos tipos celulares presentes na hemolinfa de larvas e ninfas de Rhipicephalus sanguineus (Latreille (Ixodoidea, Ixodidae em diferentes estados nutricionais Characterization of the celular types present in the Haemolymph of larvae and nimphs of Rhipicephalus sanguineus (Latreille (Ixodoidea, Ixodidae in different nutritional stages

    Directory of Open Access Journals (Sweden)

    Maria Elisa Carneiro

    1996-01-01

    Full Text Available With the purpose of characterize morphologically the hemocytes of larvae and nymphs of Rhipicephalus sanguineus on different nutritional phases, it was obtained samples of haemolymph were obtained by sectioning the forelegs and collecting the drop there formed. After dried, the samples were fixed by methanol and stained by Giemsa. Microscopical observation resulted in the characterization of five basic cellular types: prohemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids. Moreover, undefined cell types, whose morphological patterns didn't have correlation with the characteristics cited for hemocytes, were found in low frequency. The change in the relative composition of the haemolimph was characterized by decrease of the number of granulocytes and greater variabilily of the cell types present in the hemolymph as the tick evolved. This fact may be linked to the alterations that these cells suffer along the development of the tick.

  9. Occurrence of Paraprionospio sp. (form A) larvae (polychaeta: spionidae) in hypoxic water of an enclosed bay

    Science.gov (United States)

    Yokoyama, Hisashi

    1995-01-01

    Spatial and temporal distribution of larvae of Paraprionospio sp. (form A), an indicator of organic pollution in Japanese coastal waters, was investigated from May 1982 to November 1982 in Kumihama Bay, an area where oxygen-deficient water develops from late spring through autumn. This species has a less opportunistic life history represented by a seasonal peak in recruitment (September-October 1982). Simultaneously with the deoxygenation in May, larvae appeared in the bottom layer and were subsequently found through November almost exclusively in water layers with oxygen levels below 1 mg l -1. Larvae displayed no changes in vertical distribution in a 24-h study conducted in August 1980. These observations indicate that larvae have the ability to tolerate anoxic or hypoxic water throughout their entire development. It is hypothesized that the adaptation of larvae to hypoxic water may explain the high abundances of Paraprionospio sp. (form A) in organically polluted sediments.

  10. A Phosphorylcholine-Containing Glycolipid-like Antigen Present on the Surface of Infective Stage Larvae of Ascaris spp. Is a Major Antibody Target in Infected Pigs and Humans

    DEFF Research Database (Denmark)

    Vlaminck, Johnny; Masure, Dries; Wang, Tao

    2016-01-01

    Background The pig parasite Ascaris suum plays and important role in veterinary medicine and represents a suitable model for A. lumbricoides, which infects over 800 million people. In pigs, continued exposure to Ascaris induces immunity at the level of the gut, protecting the host against migrating...... larvae. The objective of this study was to identify and characterize parasite antigens targeted by this local immune response that may be crucial for parasite invasion and establishment and to evaluate their protective and diagnostic potential. Methodology/Principal Findings Pigs were immunized...... by trickle infection for 30 weeks, challenged with 2,000 eggs at week 32 and euthanized two weeks after challenge. At necropsy, there was a 100% reduction in worms recovered from the intestine and a 97.2% reduction in liver white spots in comparison with challenged non-immune control animals. Antibodies...

  11. Effects of L2 Exposure on L1 Grammar

    NARCIS (Netherlands)

    Pinto, M.

    2014-01-01

    This study explores the effects of prolonged L2 exposure on L1 grammar, and seeks to understand the extent to which mental representations of the L1 are modified under influence of the L2. The constructions under examination are overt and null subjects in Italian L1, Dutch L2 and how these forms are

  12. Avaliação da tolerância de larvas do pacamã Lophiosilurus alexandri Steindachner, 1877 (Pisces:Siluriformes a diferentes salinidades - DOI: 10.4025/actascibiolsci.v30i4.791 Evaluation of the tolerance of “pacamã” Lophiosilurus alexandri Steindachner, 1877 (Pisces:Siluriformes larvae to different salinities - DOI: 10.4025/actascibiolsci.v30i4.791

    Directory of Open Access Journals (Sweden)

    Ronald Kennedy Luz

    2008-11-01

    Full Text Available O objetivo deste trabalho foi avaliar a tolerância de larvas de pacamã Lophiosilurus alexandri ao teste agudo de salinidade da água em diferentes idades. Os testes foram realizados em larvas recém-eclodidas, com oito e 12 dias pós-eclosão. As larvas foram aclimatadas às condições experimentais por 24h, sendo estocadas em 18 tanques plásticos de 1 L na densidade de 15 larvas L-1. Após esse período, as larvas foram transferidas para as salinidades: água doce, 2, 4, 6, 8 e 10 g de sal L-1 e observadas durante 96h. Larvas recém- eclodidas apresentaram mortalidade total em 6, 8 e 10 g de sal L-1 e 100% de sobrevivência para água doce, 2 e 4 g de sal L-1; porém, com redução dos valores de peso e comprimento mediante as duas salinidades. Larvas com oito dias pós-eclosão apresentaram CL(I50-96hde 8,9 g de sal L-1. Para o peso, verificou-se redução gradativa a partir da salinidade de 2 g de sal L-1, mas sem diferenças para o comprimento das larvas entre os tratamentos. Para as larvas com 12 dias pós-eclosão, não se registraram diferenças no comprimento e peso e a sobrevivência foi menor a 8 e 10 g de sal L-1. Larvas com oito e 12 dias pós-eclosão tiveram alterações no comportamento natatório em salinidades superiores a 6 g de sal L-1. Larvas de pacamã apresentaram maior tolerância às diferentes salinidades da água com o desenvolvimento ontogenético.The aim of this study was to analyze the salinity tolerance of “pacamã” Lophiosilurus alexandri larvae at different ages. The test was conducted in post-hatching-larvae and larvae with 8 and 12 days old post-hatching. Larvae were acclimatized to experimental conditions for 24h, kept in 18 plastic tanks with 1 L at a density of 15 larvae L-1. After this period, larvae were subjected to the salinities: freshwater, 2, 4, 6, 8 and 10 g salt L-1, and observed over a period of 96h. Post-hatching larvae exhibited complete mortality in 6, 8 and 10 g salt L-1. Survival was

  13. Tracheopulmonary Myiasis Caused by a Mature Third-Instar Cuterebra Larva: Case Report and Review

    OpenAIRE

    Cornet, Muriel; Florent, Martine; Lefebvre, Aurélie; Wertheimer, Christophe; Perez-Eid, Claudine; Bangs, Michael J.; Bouvet, Anne

    2003-01-01

    Myiasis is the infestation of vertebrate tissues with fly larvae (Diptera). Most human cases in North America are subcutaneous forms due to Dermatobia hominis imported from Central and South America. Human cases of myiasis acquired in North America are rare and are primarily subdermal or ophthalmologic forms of infestation caused by early stages of Cuterebra larvae. We report an unusual case of tracheopulmonary myiasis, resulting from the in situ development of a mature cuterebrine larva asso...

  14. Impact of L1 Use in L2 English Writing Classes | Yigzaw | Ethiopian ...

    African Journals Online (AJOL)

    This experimental study endeavored to assess the impact of L1 use in pre-writing (ideagenerating) stage on L2 writing. The participants of the study were grade 11 students in Belay Zeleke Preparatory School, Bichena. A comparison between the participants' (control and experimental groups) pre-and post-writing test' ...

  15. Immune response of rainbow trout (Oncorhynchus mykiss) larvae to Yersinia ruckeri

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Kania, Per Walter; Raida, Martin Kristian

    Innate immune factors play a crucial role in survival of young fish especially during early stages of life where adaptive immunity is not fully developed. In the present study, we investigated the immune response of rainbow trout larvae (Onchorhynchus mykiss) at an early stage of development. We...... of immune factors at the transcriptional level. It may be speculated that at this stage of life, larvae may combat invading pathogens by using armour consisting of different immune factors without regulating their expression....

  16. Efficacy of moxidectin long-acting injectable formulation (1 mg/kg bodyweight) against first instar larvae of Oestrus ovis in naturally infected sheep.

    Science.gov (United States)

    Martínez-Valladares, M; Valcárcel, F; Álvarez-Sánchez, M A; Cordero-Pérez, C; Fernández-Pato, N; Frontera, E; Meana, A; Rojo-Vázquez, F A

    2013-03-31

    The objective of the current study was to evaluate the efficacy of a single treatment with a long-acting injectable formulation of moxidectin (MOX) at 1.0 mg/kg bodyweight (b.w.) against natural infection by nasal bots (Oestrus ovis) in sheep with special attention to first instar larvae (L1). Firstly, a local farm with clinical history of oestrosis was chosen to conduct the assay. A total of 49 sheep were pre-selected at the end of the summer according to the presence of evident clinical signs of infection and confirmed later by means of an indirect ELISA against excretory-secretory products from L1 to detect IgG antibodies. After that, 24 sheep were chosen to carry out the study on the basis of positive serology and age since the oldest ones were selected. The day 0 of the assay, the treatment group was administered with the MOX formulation by subcutaneous injection at the base of the left ear and the control group was administered with a saline solution in the same way. All sheep were slaughtered on day 28 post-treatment (pt). At the necropsy, the head of all sheep were cut off and split into two sagital sections and all larvae from nasal passages, septum, middle meatus, conchae and sinuses were recovered. After the necropsy, a significant number of L1 was only found in the control group and therefore the efficacy of the MOX formulation was only calculated against this stage. As a result, the formulation was 90.2% effective against L1 for sheep slaughtered at day 28 pt. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Temporal and Spatial Distribution Patterns of Echinoderm Larvae in La Parguera, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Stacey M Williams

    2010-10-01

    Full Text Available This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64μm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval bundances, oblique tows were taken with 64 and 202μm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber and Asteroidea larvae (sea star accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (~24 day old D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64mm mesh net was more efficient for collection of echinoderm larvae than the 202mm mesh net. Rev. Biol. Trop. 58 (Suppl. 3: 81-88. Epub 2010 October 01.

  18. Temporal and spatial distribution patterns of echinoderm larvae in La Parguera, Puerto Rico.

    Science.gov (United States)

    Williams, Stacey M; Jorge, García-Sais

    2010-10-01

    This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64 microm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval abundances, oblique tows were taken with 64 and 202 microm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin) exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star) ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber) and Asteroidea larvae (sea star) accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old) of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (approximately 24 day old) D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64 microm mesh net was more efficient for collection of echinoderm larvae than the 202 microm mesh net.

  19. Overview: Pyraloidea larvae (Insecta: Lepidoptera)

    Science.gov (United States)

    The larvae of pyraloid or snout moths are pests to many crops and stored products and rank as among the most destructive pests to graminaceous crops such as corn, sugarcane, and rice. On the other hand, some larvae have been investigated and used for the biological control of noxious terrestrial a...

  20. The vulnerability of gender on determiners in L1, 2L1 and L2 acquisition

    Directory of Open Access Journals (Sweden)

    Elisabeth van der Linden

    2009-01-01

    Full Text Available The acquisition of gender has been reported to be problematic for some groups of learners acquiring Germanic or Romance languages. It has been shown that L1 learners do better in gender acquisition than others, like bilingual children, child L2 learners and adult L2 learners. The reason for these differences is however not always clear. In this paper, we study the acquisition of gender on determiners by different groups of learners. We concentrate on the acquisition of French, Italian, Spanish and Dutch. The picture from a literature survey shows that contradictory results have been found. We suggest that the ‘vulnerability’ of this particular domain of grammar has to do with interacting factors in the acquisition. Among them are the specific characteristics of the language or languages involved, like the semantic and morphophonological characteristics of the nouns in each language, but also the quantity and quality of input, and the cross-linguistic influence exercised by one language on the other in a 2L1 or L2 setting. Instruction also seems to play a role.

  1. Cutaneous larva migrans

    Directory of Open Access Journals (Sweden)

    Aleksandra Wieczorek

    2016-09-01

    Full Text Available Introduction . Cutaneous larva migrans (CLM is a tropical zoonosis, caused by parasites, usually Ancylostoma braziliense. Humans are an accidental host. Polish patients with CLM are usually tourists visiting tropical and subtropical countries. The first symptoms do not always appear as creeping eruptions, which complicates the diagnosis. Objective. To present the case of a man with CLM after returning from Thailand to Poland and associated diagnostic difficulties. Case report. We present a case of a 28-year-old man who returned to Poland from Thailand. The first symptoms appeared as disseminated pruritic papules. No improvement after treatment with corticosteroids and antihistamines was observed. The diagnosis was established after the appearance of serpentine erythemas and improvement after albendazole therapy. Conclusions. In the case of returnees from exotic countries suffering from raised, pruritic rashes, and no improvement after treatment with corticosteroids and antihistamines, parasitic etiology should be considered.

  2. Immunity through early development of coral larvae.

    Science.gov (United States)

    Palmer, C V; Graham, E; Baird, A H

    2012-10-01

    As a determinant of survival, immunity is likely to be significant in enabling coral larvae to disperse and successfully recruit, however, whether reef-building coral larvae have immune defenses is unknown. We investigated the potential presence and variation in immunity in the lecithotrophic larvae of Acropora tenuis through larval development. Enzymes indicative of tyrosinase and laccase-type melanin-synthesis were quantified, and the concentration of three coral fluorescent proteins was measured over six developmental stages; egg, embryo, motile planula, planula post-exposure to crustose coralline algae (CCA; settlement cue), settled, settled post-exposure to Symbiodinium (endosymbiont). Both types of melanin-synthesis pathways and the three fluorescent proteins were present in A. tenuis throughout development. Laccase-type activity and red fluorescence increased following exposure of planula to CCA, whereas tyrosinase-type activity and cyan fluorescence increased following settlement. No change was detected in the measured parameters following exposure to Symbiodinium. This study is the first to document coral larval immune responses and suggests the melanin-synthesis pathways have disparate roles-the laccase-type potentially non-immunological and the tyrosinase-type in cytotoxic defense. Our results indicate that corals have the potential to resist infection from the earliest life history phase. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Psychotropic drugs in mixture alter swimming behaviour of Japanese medaka (Oryzias latipes) larvae above environmental concentrations.

    Science.gov (United States)

    Chiffre, Axelle; Clérandeau, Christelle; Dwoinikoff, Charline; Le Bihanic, Florane; Budzinski, Hélène; Geret, Florence; Cachot, Jérôme

    2016-03-01

    Psychiatric pharmaceuticals, such as anxiolytics, sedatives, hypnotics and antidepressors, are among the most prescribed active substances in the world. The occurrence of these compounds in the environment, as well as the adverse effects they can have on non-target organisms, justifies the growing concern about these emerging environmental pollutants. This study aims to analyse the effects of six psychotropic drugs, valproate, cyamemazine, citalopram, sertraline, fluoxetine and oxazepam, on the survival and locomotion of Japanese medaka Oryzias latipes larvae. Newly hatched Japanese medaka were exposed to individual compounds for 72 h, at concentrations ranging from 10 μg L(-1) to 10 mg L(-1). Lethal concentrations 50 % (LC50) were estimated at 840, 841 and 9,136 μg L(-1) for fluoxetine, sertraline and citalopram, respectively, while other compounds did not induce any significant increase in mortality. Analysis of the swimming behaviour of larvae, including total distance moved, mobility and location, provided an estimated lowest observed effect concentration (LOEC) of 10 μg L(-1) for citalopram and oxazepam, 12.2 μg L(-1) for cyamemazine, 100 μg L(-1) for fluoxetine, 1,000 μg L(-1) for sertraline and >10,000 μg L(-1) for valproate. Realistic environmental mixture of the six psychotropic compounds induced disruption of larval locomotor behaviour at concentrations about 10- to 100-fold greater than environmental concentrations.

  4. Ubiquitin C-Terminal Hydrolase L1 in Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Jennifer Hurst-Kennedy

    2012-01-01

    Full Text Available Ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1, aka PGP9.5 is an abundant, neuronal deubiquitinating enzyme that has also been suggested to possess E3 ubiquitin-protein ligase activity and/or stabilize ubiquitin monomers in vivo. Recent evidence implicates dysregulation of UCH-L1 in the pathogenesis and progression of human cancers. Although typically only expressed in neurons, high levels of UCH-L1 have been found in many nonneuronal tumors, including breast, colorectal, and pancreatic carcinomas. UCH-L1 has also been implicated in the regulation of metastasis and cell growth during the progression of nonsmall cell lung carcinoma, colorectal cancer, and lymphoma. Together these studies suggest UCH-L1 has a potent oncogenic role and drives tumor development. Conversely, others have observed promoter methylation-mediated silencing of UCH-L1 in certain tumor subtypes, suggesting a potential tumor suppressor role for UCH-L1. In this paper, we provide an overview of the evidence supporting the involvement of UCH-L1 in tumor development and discuss the potential mechanisms of action of UCH-L1 in oncogenesis.

  5. First report of antennular attachment organs in a barnacle nauplius larva

    DEFF Research Database (Denmark)

    Watanabe, H.; Høeg, Jens Thorvald; Chan, B.K.K.

    2008-01-01

    Larvae released from Newmaniverruca albatrossiana were cultured in the laboratory until the cypris stage. The brood size of individuals was low, about 60 larvae per brood. The exact number of instars was not determined. Early instars had the morphology normally seen in lecithotrophic nauplii...

  6. Description of the Larva of a New Species of the Genus Afronurus ...

    African Journals Online (AJOL)

    A new species of Afronurus, A. opa sp. n., (Ephemeroptera: Heptageniidae), from Opa River catchment basin, Nigeria is described from the larval stage. The diagnostic morphological characters of the larva are illustrated and discussed. Keywords: Afronurus opa sp. n. larva, Heptageniidae, Ephemeroptera, Nigeria. Tropical ...

  7. Drosophila FoxL1 non-autonomously coordinates organ placement during embryonic development.

    Science.gov (United States)

    Hanlon, Caitlin D; Andrew, Deborah J

    2016-11-15

    Determining how organs attain precise positioning within an organism is a crucial facet of developmental biology. The Fox family winged-helix transcription factors are known to play key roles in development of multiple organs. Drosophila FoxL1 (aka Fd64A) is dynamically expressed in embryos but its function is completely uncharacterized. FoxL1 is expressed in a single group of body wall - muscles in the 2nd and 3rd thoracic segments, in homologous abdominal muscles at earlier stages, and in the hindgut mesoderm from early through late embryogenesis. We show that FoxL1 expression in T2 and T3 is in VIS5, which is not a single muscle spanning the entire thorax, as previously published, but is, instead, three individual muscles, each spanning a single thoracic segment. We generate mutations in foxL1 and show that, surprisingly, none of the tissues that express FoxL1 are affected by its loss. Instead, loss of foxL1 results in defects in salivary gland positioning and morphology, as well as defects in the migration of hemocytes, germ cells and Malpighian tubules. We also show that FoxL1-dependent expression of secreted Sema2a in T3 VIS5 is required for normal salivary gland positioning. Altogether, these findings suggest that Drosophila FoxL1 functions like its mammalian counterpart in non-autonomously orchestrating the behaviors of surrounding tissues. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Regulation of Life Cycle Checkpoints and Developmental Activation of Infective Larvae in Strongyloides stercoralis by Dafachronic Acid.

    Directory of Open Access Journals (Sweden)

    Mennatallah M Y Albarqi

    2016-01-01

    Full Text Available The complex life cycle of the parasitic nematode Strongyloides stercoralis leads to either developmental arrest of infectious third-stage larvae (iL3 or growth to reproductive adults. In the free-living nematode Caenorhabditis elegans, analogous determination between dauer arrest and reproductive growth is governed by dafachronic acids (DAs, a class of steroid hormones that are ligands for the nuclear hormone receptor DAF-12. Biosynthesis of DAs requires the cytochrome P450 (CYP DAF-9. We tested the hypothesis that DAs also regulate S. stercoralis development via DAF-12 signaling at three points. First, we found that 1 μM Δ7-DA stimulated 100% of post-parasitic first-stage larvae (L1s to develop to free-living adults instead of iL3 at 37°C, while 69.4±12.0% (SD of post-parasitic L1s developed to iL3 in controls. Second, we found that 1 μM Δ7-DA prevented post-free-living iL3 arrest and stimulated 85.2±16.9% of larvae to develop to free-living rhabditiform third- and fourth-stages, compared to 0% in the control. This induction required 24-48 hours of Δ7-DA exposure. Third, we found that the CYP inhibitor ketoconazole prevented iL3 feeding in host-like conditions, with only 5.6±2.9% of iL3 feeding in 40 μM ketoconazole, compared to 98.8±0.4% in the positive control. This inhibition was partially rescued by Δ7-DA, with 71.2±16.4% of iL3 feeding in 400 nM Δ7-DA and 35 μM ketoconazole, providing the first evidence of endogenous DA production in S. stercoralis. We then characterized the 26 CYP-encoding genes in S. stercoralis and identified a homolog with sequence and developmental regulation similar to DAF-9. Overall, these data demonstrate that DAF-12 signaling regulates S. stercoralis development, showing that in the post-parasitic generation, loss of DAF-12 signaling favors iL3 arrest, while increased DAF-12 signaling favors reproductive development; that in the post-free-living generation, absence of DAF-12 signaling is crucial for

  9. Oviposition Behavior in Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in Response to the Presence of Heterospecific and Conspecific Larvae.

    Science.gov (United States)

    Gonzalez, Paula V; González Audino, Paola A; Masuh, Héctor M

    2016-03-01

    In mosquitoes, location of suitable sites for oviposition requires a set of visual, tactile, and olfactory cues that influences females before laying their eggs. The ability of gravid females to distinguish among potential oviposition sites that will or will not support the growth, development, and survival of their progeny is critical. Aedes aegypti (L.) and Aedes albopictus (Skuse) share ecological niches, being highly competitive in larval stage. We studied the oviposition behavior of both species in the presence of larvae of one or the other species (heterospecific or conspecific larvae). The number of eggs laid by gravid females on oviposition sites (water with different or the same species of Aedes larvae) were compared. The presence and density of heterospecific or conspecific larvae had a positive or negative effect on the ovipositional responses, measured as an oviposition activity index. For both species, the oviposition was not affected by heterospecific larvae with densities between 10 and 100 larvae in water, but a strong attractant behavior was observed for a density of 500 larvae in water. For Ae. albopictus in the presence of larvae of the same species (conspecific oviposition), we observed an attractant effect for larvae density of 10 but not for 100 or 500 larvae in water. Instead, for Ae. aegypti, we observed attraction only for 100 larvae, not for 10 or 500 larvae. Results presented here provide an additional insight about oviposition behavior responses of gravid females in the presence of conspecific and heterospecific larvae in breeding sites.

  10. Biorheological action of Ascaris lumbricoides larvae on human erythrocytes.

    Science.gov (United States)

    de León, Patricia Ponce; Del Balzo, Gonzalo; Riquelme, Bibiana

    2013-03-01

    Previous studies have shown that A. lumbricoides extracts capture sialic acid (SA) from human red blood cells (RBC). The aim of this work was to study hemorheological alterations in vitro caused by parasite larvae. The biorheological action of three larva concentrates of first and second larval stage on group O erythrocytes was analyzed by incubating the erythrocyte packed together with an equal volume of larvae (treated RBC) and PBS (control RBC). Distribution and parameters of aggregation (digital image analysis), aggregation kinetics (erythroaggregameter), and viscoelasticity (erythrodeformeter) were measured. The digital image analysis showed that all the larvae diminished the isolated cells percentage and increased the size of the formed aggregates. The aggregate formation velocity was lower in the treated than in the control. The deformability index (ID) values of treated RBC did not present variations with respect to those of the control, but a decrease in the erythrocyte elastic modulus (μ(m)) and membrane surface viscosity (η(m)) values was observed, indicating that the larvae not only induced a diminution in the membrane surface viscosity of RBC but also altered the dynamic viscoelasticity of the membrane. Experiments carried out in vitro support the conclusion that the contact between larvae and RBC produces hemorheological alterations.

  11. Quantification of vestibular-induced eye movements in zebrafish larvae

    Directory of Open Access Journals (Sweden)

    Mo Weike

    2010-09-01

    Full Text Available Abstract Background Vestibular reflexes coordinate movements or sensory input with changes in body or head position. Vestibular-evoked responses that involve the extraocular muscles include the vestibulo-ocular reflex (VOR, a compensatory eye movement to stabilize retinal images. Although an angular VOR attributable to semicircular canal stimulation was reported to be absent in free-swimming zebrafish larvae, recent studies reveal that vestibular-induced eye movements can be evoked in zebrafish larvae by both static tilts and dynamic rotations that tilt the head with respect to gravity. Results We have determined herein the basis of sensitivity of the larval eye movements with respect to vestibular stimulus, developmental stage, and sensory receptors of the inner ear. For our experiments, video recordings of larvae rotated sinusoidally at 0.25 Hz were analyzed to quantitate eye movements under infrared illumination. We observed a robust response that appeared as early as 72 hours post fertilization (hpf, which increased in amplitude over time. Unlike rotation about an earth horizontal axis, rotation about an earth vertical axis at 0.25 Hz did not evoke eye movements. Moreover, vestibular-induced responses were absent in mutant cdh23 larvae and larvae lacking anterior otoliths. Conclusions Our results provide evidence for a functional vestibulo-oculomotor circuit in 72 hpf zebrafish larvae that relies upon sensory input from anterior/utricular otolith organs.

  12. Long-wavelength photosensitivity in coral planula larvae.

    Science.gov (United States)

    Mason, Benjamin M; Cohen, Jonathan H

    2012-04-01

    Light influences the swimming behavior and settlement of the planktonic planula larvae of coral, but little is known regarding the photosensory biology of coral at this or any life-history stage. Here we used changes in the electrical activity of coral planula tissue upon light flashes to investigate the photosensitivity of the larvae. Recordings were made from five species: two whose larvae are brooded and contain algal symbionts (Porites astreoides and Agaricia agaricites), and three whose larvae are spawned and lack algal symbionts (Acropora cervicornis, Acropora palmata,and Montastrea faveolata). Photosensitivity originated from the coral larva rather than from, or in addition to, its algal symbionts as species with and without symbionts displayed similar tissue-level electrical responses to light. All species exhibited as much (or more) sensitivity to red stimuli as to blue/green stimuli, which is consistent with a role for long-wavelength visible light in the preference for substrata observed during settlement and in facilitating vertical positioning of larvae in the water column.

  13. Acute toxicity of five pesticides to Apis mellifera larvae reared in vitro.

    Science.gov (United States)

    Dai, Pingli; Jack, Cameron J; Mortensen, Ashley N; Ellis, James D

    2017-11-01

    The reported high loss rates of managed honey bee colonies have been attributed to diverse stressors including pesticides. Honey bee larvae can be exposed to pesticides in contaminated nectar, pollen and wax. Due to the difficulties of rearing larvae in vitro, research focusing on adult bee exposure to pesticides is more common than that on larva exposure to pesticides. Herein, we aimed to assess the acute toxicity of five insecticides to honey bee larvae using an improved in vitro rearing method. LC 50 and LD 50 were calculated for larvae at 72 h following a single diet exposure administered when the larvae were 84 ± 12 h old. Solvent control larval mortalities were less than 15% at 72 h. The LC 50 values (mg L -1 ) for each tested pesticide were as follows: amitraz, 494.27; chlorpyrifos, 15.39; coumaphos, 90.01; fluvalinate, 27.69; and imidacloprid, 138.84. The LD 50 values in µg per larva were 14.83 (amitraz), 0.46 (chlorpyrifos), 2.70 (coumaphos), 0.83 (fluvalinate) and 4.17 (imidacloprid). The toxicity of the test pesticides to honey bee larvae from most to least toxic was chlorpyrifos > fluvalinate > coumaphos = imidacloprid > amitraz. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Sensitivity of larvae, pupae, and adults of the driedfruit beetle (Coleoptera: Nitidulidae) to gamma radiation

    International Nuclear Information System (INIS)

    Johnson, J.A.

    1987-01-01

    Raisins infested with three different ages of larvae of dried fruit beetle, Carpophilus hemipterus (L.), were treated with gamma radiation doses of 130-798 Gy. Pupae and unmated adults were also treated at 338 and 486 Gy. All doses to larvae prevented adult development. Only the oldest treated larvae were able to develop to the wandering stage (late third instar) before dying. Complete larval mortality occurred sooner at higher doses. Most younger larvae died within the raisins. Mortality of irradiated pupae at both doses was 90%, and adults emerging from treated pupae died within 48 h. Irradiated adults produced no progeny and died within 1 wk after treatment

  15. Robust L1-norm two-dimensional linear discriminant analysis.

    Science.gov (United States)

    Li, Chun-Na; Shao, Yuan-Hai; Deng, Nai-Yang

    2015-05-01

    In this paper, we propose an L1-norm two-dimensional linear discriminant analysis (L1-2DLDA) with robust performance. Different from the conventional two-dimensional linear discriminant analysis with L2-norm (L2-2DLDA), where the optimization problem is transferred to a generalized eigenvalue problem, the optimization problem in our L1-2DLDA is solved by a simple justifiable iterative technique, and its convergence is guaranteed. Compared with L2-2DLDA, our L1-2DLDA is more robust to outliers and noises since the L1-norm is used. This is supported by our preliminary experiments on toy example and face datasets, which show the improvement of our L1-2DLDA over L2-2DLDA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Direct anthelmintic effects of a purified chicory extract against free-living stages of Cooperia oncophora: preliminary results

    DEFF Research Database (Denmark)

    Pena-Espinoza, Miguel Angel; Williams, A.; Enemark, Heidi L.

    2013-01-01

    concentrations ranging from 5 to 0.12 mg dry matter (DM)/mL. Two Jersey calves (4 months old) mono-infected with C. oncophora were used for collection of nematode eggs. Isolated eggs were used in an egg hatch assay (EHA) with 6 concentrations of the chicory extract (tested in duplicates, final DMSO concentration......Direct anthelmintic effects of a purified extract from chicory (Cichorium intybus L.) were assessed on eggs and first-stage larvae (L1) of C. oncophora. Chicory leaves (cv. Spadona) were collected from an organic dairy farm in Denmark. Dried leaf tissue was extracted in a Soxhlet apparatus...

  17. On L1-convergence of Walsh-Fourier series

    Directory of Open Access Journals (Sweden)

    C. W. Onneweer

    1978-01-01

    Full Text Available Let G denote the dyadic group, which has as its dual group the Walsh(-Paley functions. In this paper we formulate a condition for functions in L1(G which implies that their Walsh-Fourier series converges in L1(G-norm. As a corollary we obtain a Dini-Lipschitz-type theorem for L1(G convergence and we prove that the assumption on the L1(G modulus of continuity in this theorem cannot be weakened. Similar results also hold for functions on the circle group T and their (trigonometric Fourier series.

  18. Defensive enrolment in mantis shrimp larvae (Malacostraca: Stomatopoda)

    NARCIS (Netherlands)

    Haug, C.; Haug, J.T.

    2014-01-01

    We describe a possible new defensive behaviour of larval stages of mantis shrimps (Stomatopoda). Mantis shrimp larvae are rarely observed in nature, thus the study is based on postures of museum material and functional morphological aspects. Specimens described here are tightly enrolled, their pleon

  19. Hydrodynamics of burst swimming fish larvae; a conceptual model approach

    NARCIS (Netherlands)

    Verhagen, J.H.G.

    2004-01-01

    Burst swimming of fish larvae is analysed from a hydrodynamic point of view. A picture of the expected flow pattern is presented based on information in literature on unsteady-flow patterns around obstacles in the intermediate Reynolds number region. It is shown that the acceleration stage of burst

  20. Food web changes under ocean acidification promote herring larvae survival.

    Science.gov (United States)

    Sswat, Michael; Stiasny, Martina H; Taucher, Jan; Algueró-Muñiz, Maria; Bach, Lennart T; Jutfelt, Fredrik; Riebesell, Ulf; Clemmesen, Catriona

    2018-05-01

    Ocean acidification-the decrease in seawater pH due to rising CO 2 concentrations-has been shown to lower survival in early life stages of fish and, as a consequence, the recruitment of populations including commercially important species. To date, ocean-acidification studies with fish larvae have focused on the direct physiological impacts of elevated CO 2 , but largely ignored the potential effects of ocean acidification on food web interactions. In an in situ mesocosm study on Atlantic herring (Clupea harengus) larvae as top predators in a pelagic food web, we account for indirect CO 2 effects on larval survival mediated by changes in food availability. The community was exposed to projected end-of-the-century CO 2 conditions (~760 µatm pCO 2 ) over a period of 113 days. In contrast with laboratory studies that reported a decrease in fish survival, the survival of the herring larvae in situ was significantly enhanced by 19 ± 2%. Analysis of the plankton community dynamics suggested that the herring larvae benefitted from a CO 2 -stimulated increase in primary production. Such indirect effects may counteract the possible direct negative effects of ocean acidification on the survival of fish early life stages. These findings emphasize the need to assess the food web effects of ocean acidification on fish larvae before we can predict even the sign of change in fish recruitment in a high-CO 2 ocean.

  1. Acute ecotoxicology of natural oil and gas condensate to coral reef larvae

    Science.gov (United States)

    Negri, Andrew P.; Brinkman, Diane L.; Flores, Florita; Botté, Emmanuelle S.; Jones, Ross J.; Webster, Nicole S.

    2016-02-01

    Risks posed by oil spills to coral reefs are difficult to evaluate, partially due to the absence of studies that adequately assess toxicity to relevant coral reef species. Here we experimentally tested the acute toxicity of condensate, representing a fraction of light crude oil, to coral (Acropora tenuis) and sponge (Rhopaloeides odorabile) larvae. The metamorphosis of coral larvae was inhibited at total petroleum aromatic hydrocarbon (TPAH) concentrations of water accommodated fractions (WAF) as low as 103 μg l-1, similar to concentrations detected in seawater following large spills. The sensitivity of coral larvae increased by 40% when co-exposed to UV light that they might encounter in shallow reefal systems. Condensate WAF was more toxic to coral larvae than predicted by summing the toxicity of its main components (benzene, toluene, p-xylene and napthalene). In contrast, the sensitivity of sponge larvae to condensate WAF (>10,000 μg l-1 TPAH) was far less than coral in the presence and absence of UV, but similar to that of other marine invertebrates. While these results highlight the relative sensitivity of coral larvae to oil, further research is needed to better understand and predict the impacts and risks posed by hydrocarbons to tropical reef systems.

  2. Phage therapy as an approach to prevent Vibrio anguillarum infections in fish larvae production.

    Directory of Open Access Journals (Sweden)

    Yolanda J Silva

    Full Text Available Fish larvae in aquaculture have high mortality rates due to pathogenic bacteria, especially the Vibrio species, and ineffective prophylactic strategies. Vaccination is not feasible in larvae and antibiotics have reduced efficacy against multidrug resistant bacteria. A novel approach to controlling Vibrio infections in aquaculture is needed. The potential of phage therapy to combat vibriosis in fish larvae production has not yet been examined. We describe the isolation and characterization of two bacteriophages capable of infecting pathogenic Vibrio and their application to prevent bacterial infection in fish larvae. Two groups of zebrafish larvae were infected with V. anguillarum (∼106 CFU mL-1 and one was later treated with a phage lysate (∼108 PFU mL-1. A third group was only added with phages. A fourth group received neither bacteria nor phages (fish control. Larvae mortality, after 72 h, in the infected and treated group was similar to normal levels and significantly lower than that of the infected but not treated group, indicating that phage treatment was effective. Thus, directly supplying phages to the culture water could be an effective and inexpensive approach toward reducing the negative impact of vibriosis in larviculture.

  3. Phage therapy as an approach to prevent Vibrio anguillarum infections in fish larvae production.

    Science.gov (United States)

    Silva, Yolanda J; Costa, Liliana; Pereira, Carla; Mateus, Cristiana; Cunha, Angela; Calado, Ricardo; Gomes, Newton C M; Pardo, Miguel A; Hernandez, Igor; Almeida, Adelaide

    2014-01-01

    Fish larvae in aquaculture have high mortality rates due to pathogenic bacteria, especially the Vibrio species, and ineffective prophylactic strategies. Vaccination is not feasible in larvae and antibiotics have reduced efficacy against multidrug resistant bacteria. A novel approach to controlling Vibrio infections in aquaculture is needed. The potential of phage therapy to combat vibriosis in fish larvae production has not yet been examined. We describe the isolation and characterization of two bacteriophages capable of infecting pathogenic Vibrio and their application to prevent bacterial infection in fish larvae. Two groups of zebrafish larvae were infected with V. anguillarum (∼106 CFU mL-1) and one was later treated with a phage lysate (∼108 PFU mL-1). A third group was only added with phages. A fourth group received neither bacteria nor phages (fish control). Larvae mortality, after 72 h, in the infected and treated group was similar to normal levels and significantly lower than that of the infected but not treated group, indicating that phage treatment was effective. Thus, directly supplying phages to the culture water could be an effective and inexpensive approach toward reducing the negative impact of vibriosis in larviculture.

  4. Acute ecotoxicology of natural oil and gas condensate to coral reef larvae.

    Science.gov (United States)

    Negri, Andrew P; Brinkman, Diane L; Flores, Florita; Botté, Emmanuelle S; Jones, Ross J; Webster, Nicole S

    2016-02-19

    Risks posed by oil spills to coral reefs are difficult to evaluate, partially due to the absence of studies that adequately assess toxicity to relevant coral reef species. Here we experimentally tested the acute toxicity of condensate, representing a fraction of light crude oil, to coral (Acropora tenuis) and sponge (Rhopaloeides odorabile) larvae. The metamorphosis of coral larvae was inhibited at total petroleum aromatic hydrocarbon (TPAH) concentrations of water accommodated fractions (WAF) as low as 103 μg l(-1), similar to concentrations detected in seawater following large spills. The sensitivity of coral larvae increased by 40% when co-exposed to UV light that they might encounter in shallow reefal systems. Condensate WAF was more toxic to coral larvae than predicted by summing the toxicity of its main components (benzene, toluene, p-xylene and napthalene). In contrast, the sensitivity of sponge larvae to condensate WAF (>10,000 μg l(-1) TPAH) was far less than coral in the presence and absence of UV, but similar to that of other marine invertebrates. While these results highlight the relative sensitivity of coral larvae to oil, further research is needed to better understand and predict the impacts and risks posed by hydrocarbons to tropical reef systems.

  5. Lethal concentration (CL50 of un-ionized ammonia for pejerrey larvae in acute exposure

    Directory of Open Access Journals (Sweden)

    Piedras Sérgio Renato Noguez

    2006-01-01

    Full Text Available Ammonia results from decomposition of effluents organic matter, e.g. feed wastes and fish faeces. Its un-ionized form can be toxic because diffuses easily through fish respiratory membranes, damaging gill epithelium and impairing gas exchanges. The objective of this work was determining the 96-hour CL50 of un-ionized ammonia for newly hatched pejerrey Odontesthes bonariensis larvae. Trials were set up completely randomized design, with three different concentration of un-ionized ammonia (0.57, 0.94, and 1.45 mg L-1 NH3-N and a control treatment (n = 3. Experimental units were 20-L, aerated aquaria stocked with 20 larvae (average weight 3.9 mg. Pejerrey larvae exposed to un-ionized ammonia during 96 hours present 50% mortality at 0.71 mg L-1 NH3-N.

  6. Amino Acid Absorption by Tiger Grouper Fish (Epinephelus fuscoguttatus Larvae. (Absorbsi Asam Amino oleh Larva Ikan Kerapu Macan (Epinephelus fuscoguttatus

    Directory of Open Access Journals (Sweden)

    Ambariyanto Ambariyanto

    2013-12-01

    cultivation i.e. high mortality rate at larva stage. Many different efforts have been done to overcome this problem mainly by using drugs and antibiotics, which have caused another problem i.e. bacteria resitance. One aspect that has not been widely investigated is by increasing its growth rate so that the larvae will have the ability to avoid mortality, such as by utilising dissolved organic matter (DOM which naturally occur in the environment. This research investigates the question whether Kerapu fish larvae have the ability to absorb DOM (in this case disolved free amino acids; DAA as well as the preference and the rate of absorbsion. There were 16 species of DAA used in this experiment which consist of three classes i.e. neutral, basic, and acidic. Two days old larvae were used in the experimant. The results showed that Kerapu larvae absorbed all classes of amino acids, although not all amino acids given being absorbed but only glutamine, histidine, lysin, serine, triptophan, metionine and iso leusine. While the most absorbed amino acids was lysine. One interesting results showed that the larvae secrete several amino acids i.e. glysine, alanine, tyrosine, valine, phenil alanine and leusine. The absorbsion and secretion of amino acids were possibly related to its metabolic processes within the larvae in relation to growth processes. Keywords: dissolved free amino acids, DAA, larvae, Kerapu, Epinephelus fuscoguttatus

  7. Embedded aspect in L2 acquisition: Evidence from L1 Russian learners of Greek

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    Sviatlana Karpava

    2013-06-01

    Full Text Available This work investigates first language (L1 influence on the second language (L2 acquisition of aspect, comparing participants with homogeneous L1 background (Russian in Mainland Greece (L2 Standard Modern Greek and Cyprus (L2 Cypriot Greek, where verb complementation takes a finite form instead of an infinitival as is possible in Russian. Focus of the experimental study lies on embedded environments, which require only perfective aspect in Greek but allow either perfective or imperfective in Russian. The findings support the Full Transfer/Full Access Hypothesis, according to which aspect is part of Universal Grammar and L2 learners can reach native-like attainment due to access to it, while at the initial stage of L2 acquisition transfer from L1 into L2 takes place.

  8. Morphogenesis of Strongyloides stercoralis infective larvae requires the DAF-16 ortholog FKTF-1.

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    Michelle L Castelletto

    2009-04-01

    Full Text Available Based on metabolic and morphological similarities between infective third-stage larvae of parasitic nematodes and dauer larvae of Caenorhabditis elegans, it is hypothesized that similar genetic mechanisms control the development of these forms. In the parasite Strongyloides stercoralis, FKTF-1 is an ortholog of DAF-16, a forkhead transcription factor that regulates dauer larval development in C. elegans. Using transgenesis, we investigated the role of FKTF-1 in S. stercoralis' infective larval development. In first-stage larvae, GFP-tagged recombinant FKTF-1b localizes to the pharynx and hypodermis, tissues remodeled in infective larvae. Activating and inactivating mutations at predicted AKT phosphorylation sites on FKTF-1b give constitutive cytoplasmic and nuclear localization of the protein, respectively, indicating that its post-translational regulation is similar to other FOXO-class transcription factors. Mutant constructs designed to interfere with endogenous FKTF-1b function altered the intestinal and pharyngeal development of the larvae and resulted in some transgenic larvae failing to arrest in the infective stage. Our findings indicate that FKTF-1b is required for proper morphogenesis of S. stercoralis infective larvae and support the overall hypothesis of similar regulation of dauer development in C. elegans and the formation of infective larvae in parasitic nematodes.

  9. Monoclonal antibody against recombinant Fasciola gigantica cathepsin L1H could detect juvenile and adult cathepsin Ls of Fasciola gigantica.

    Science.gov (United States)

    Wongwairot, Sirima; Kueakhai, Pornanan; Changklungmoa, Narin; Jaikua, Wipaphorn; Sansri, Veerawat; Meemon, Krai; Songkoomkrong, Sineenart; Riengrojpitak, Suda; Sobhon, Prasert

    2015-01-01

    Cathepsin Ls (CatLs), the major cysteine protease secreted by Fasciola spp., are important for parasite digestion and tissue invasion. Fasciola gigantica cathepsin L1H (FgCatL1H) is the isotype expressed in the early stages for migration and invasion. In the present study, a monoclonal antibody (MoAb) against recombinant F. gigantica cathepsin L1H (rFgCatL1H) was produced by hybridoma technique using spleen cells from BALB/c mice immunized with recombinant proFgCatL1H (rproFgCatL1H). This MoAb is an immunoglobulin (Ig)G1 with κ light chain isotype. The MoAb reacted specifically with rproFgCatL1H, the native FgCatL1H at a molecular weight (MW) 38 to 48 kDa in the extract of whole body (WB) of metacercariae and newly excysted juvenile (NEJ) and cross-reacted with rFgCatL1 and native FgCatLs at MW 25 to 28 kDa in WB of 2- and 4-week-old juveniles, adult, and adult excretory-secretory (ES) fractions by immunoblotting and indirect ELISA. It did not cross-react with antigens in WB fractions from other parasites, including Gigantocotyle explanatum, Paramphistomum cervi, Gastrothylax crumenifer, Eurytrema pancreaticum, Setaria labiato-papillosa, and Fischoederius cobboldi. By immunolocalization, MoAb against rFgCatL1H reacted with the native protein in the gut of metacercariae and NEJ and also cross-reacted with CatL1 in 2- and 4-week-old juveniles and adult F. gigantica. Therefore, FgCatL1H and its MoAb may be used for immunodiagnosis of both early and late fasciolosis in ruminants and humans.

  10. Scanning electron microscope observations of brine shrimp larvae from space shuttle experiments

    Science.gov (United States)

    DeBell, L.; Paulsen, A.; Spooner, B.

    1992-01-01

    Brine shrimp are encysted as gastrula stage embryos, and may remain dehydrated and encysted for years without compromising their viability. This aspect of brine shrimp biology is desirable for studying development of animals during space shuttle flight, as cysts placed aboard a spacecraft may be rehydrated at the convenience of an astronaut, guaranteeing that subsequent brine shrimp development occurs only on orbit and not on the pad during launch delays. Brine shrimp cysts placed in 5 ml syringes were rehydrated with salt water and hatched during a 9 day space shuttle mission. Subsequent larvae developed to the 8th larval stage in the sealed syringes. We studied the morphogenesis of the brine shrimp larvae and found the larvae from the space shuttle experiments similar in rate of growth and extent of development, to larvae grown in sealed syringes on the ground. Extensive differentiation and development of embryos and larvae can occur in a microgravity environment.

  11. Some results about operators on L 1 | Riel | Quaestiones ...

    African Journals Online (AJOL)

    µ). Among these, we show that if T is a bounded linear operator on L1(µ) which acts as a Hilbert-Schmidt operator on L2(µ), then T : L11(µ) L1(µ) is representable. Mathematics Subject Classification (2010): 46G10, 47B10, 47B38. Key words: ...

  12. Attitudes held by Setswana L1-speaking university students toward ...

    African Journals Online (AJOL)

    Respondents believed that their L1 had limitations in wider society; and that it had prestige, albeit a covert one. Generally, they held favourable attitudes toward their L1. Further comprehensive research needs to be done to explore these new variables, as well as to explore their statistical significance in language attitude ...

  13. On the Link Between L1-PCA and ICA.

    Science.gov (United States)

    Martin-Clemente, Ruben; Zarzoso, Vicente

    2017-03-01

    Principal component analysis (PCA) based on L1-norm maximization is an emerging technique that has drawn growing interest in the signal processing and machine learning research communities, especially due to its robustness to outliers. The present work proves that L1-norm PCA can perform independent component analysis (ICA) under the whitening assumption. However, when the source probability distributions fulfil certain conditions, the L1-norm criterion needs to be minimized rather than maximized, which can be accomplished by simple modifications on existing optimal algorithms for L1-PCA. If the sources have symmetric distributions, we show in addition that L1-PCA is linked to kurtosis optimization. A number of numerical experiments illustrate the theoretical results and analyze the comparative performance of different algorithms for ICA via L1-PCA. Although our analysis is asymptotic in the sample size, this equivalence opens interesting new perspectives for performing ICA using optimal algorithms for L1-PCA with guaranteed global convergence while inheriting the increased robustness to outliers of the L1-norm criterion.

  14. L 1 Generalized Procrustes 2D Shape Alignment

    DEFF Research Database (Denmark)

    Larsen, Rasmus

    2008-01-01

    to the precision needed. Using 3 coordinate systems rotated 30 degrees we get a 12 sided regular polygon, with which we achieve deviations from Euclidean distances less than 2 % over all directions. This new formulation allows for minimization in the L1-norm using LP. We demonstrate that the use of the L1-norm...

  15. Color variability and body size of larvae of two Epomis species (Coleoptera: Carabidae in Israel

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    Gil Wizen

    2011-07-01

    Full Text Available Species identification using the characteristics of developmental stages is challenging. However, for insect taxonomy the coloration of larval stages can be an informative feature. The use of live specimens is recommended for this because the color fades in preserved specimens. In this study we examine the possibility of using variation in coloration and color pattern of larvae in order to distinguish between two ground beetles species Epomis dejeani Dejean, 1831 and E. circumscriptus Duftschmid, 1812. We present an atlas and describe the coloration and body size of the three larval stages of the above species based on live specimens. The first instar larvae of the two Epomis species can be easily distinguished based on their color. From the second instar on, the variability in coloration and color patterns increases, creating an overlap in these attributes between larvae of the two species. Except for minor differences in color of the antennae and the base of the mandibles, larvae of the two species are indistinguishable at the second and third larval stages. To the best of our knowledge this is the first attempt to use variation in coloration and color pattern in live larvae in order to identify coleopterans. The color atlas of the larvae enables simple separation of the two Epomis species without requiring sophisticated magnifying devices, although it is less straightforward at the second and third larval stages. We found similar body lengths between the two species for all developmental stages, except for third instar larvae prior to pupation. In the two species the difference in larval body length before pupation positively correlated with that of the adult beetles. More than 70% of the adults' length can be explained by the length of the late third-instar larva; i.e. the large larvae develop into large adults. The larger specimens are the females.

  16. Culturing larvae of marine invertebrates.

    Science.gov (United States)

    Strathmann, Richard R

    2014-01-01

    Larvae of marine invertebrates cultured in the laboratory experience conditions that they do not encounter in nature, but development and survival to metamorphic competence can be obtained in such cultures. This protocol emphasizes simple methods suitable for a wide variety of larvae. Culturing larvae requires seawater of adequate quality and temperature within the tolerated range. Beyond that, feeding larvae require appropriate food, but a few kinds of algae and animals are sufficient as food for diverse larvae. Nontoxic materials include glass, many plastics, hot-melt glue, and some solvents, once evaporated. Cleaners that do not leave toxic residues after rinsing include dilute hydrochloric or acetic acid, sodium hypochlorite (commercial bleach), and ethanol. Materials that can leave toxic residues, such as formaldehyde, glutaraldehyde, detergents, and hand lotions, should be avoided, especially with batch cultures that lack continuously renewed water. Reverse filtration can be used to change water gently at varying frequencies, depending on temperature and the kinds of food that are provided. Bacterial growth can be limited by antibiotics, but antibiotics are often unnecessary. Survival and growth are increased by low concentrations of larvae and stirring of large or dense cultures. One method of stirring large numbers of containers is a rack of motor-driven paddles. Most of the methods and materials are inexpensive and portable. If necessary, a room within a few hours of the sea could be temporarily equipped for larval culture.

  17. Growth and survival of silver catfish larvae, Rhamdia quelen (Heptapteridae, at different calcium and magnesium concentrations

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    Lenise Vargas Flores da Silva

    Full Text Available Since the relative ratios of Ca2+ and Mg2+ can vary greatly from one water body to another, and lime used for the increase of water hardness or pH can have different ratios of Ca2+ and Mg2+ in its composition, the objective of this study was to analyze the growth and survival of silver catfish, Rhamdia quelen, larvae at different calcium and magnesium concentrations. After fertilization, eggs were randomly divided into 4 treatments (three replicates per treatment with different concentrations of Ca2+ and Mg2+ at hardness values of 70 mg.L-1 CaCO3 (mg.L-1 : 5.2 Ca2+ and 14.12 Mg2+; 13.11 Ca2+ and 7.11 Mg2+; 20.26 Ca2+ and 2.86 Mg2+; 24.95 Ca2+ and 0.95 Mg2+ and 150 mg.L-1 CaCO3 (mg.L-1 : 5.2 Ca2+ and 32.70 Mg2+; 28.63 Ca2+ and 16.44 Mg2+; 44.68 Ca2+and 6.44 Mg2+; 62.78 Ca2+ and 0.95 Mg2+. There was also another group exposed to water hardness of 20 mg.L-1 CaCO3 (Ca2+ 5.2 mg.L-1 and Mg2+ 0.95 mg.L-1 at both experiments. The post-hatch larvae were transferred to continuously aerated 40 L polyethylene aquaria (400 larvae/tank containing the same water as used for incubation. Samples of larvae were collected on days 0, 7, 14, and 21, and the length, weight, and specific growth rate were determined for each collection. Survival and biomass were calculated on day 21. At water hardness of 70 mg.L-1 CaCO3, the best survival and growth of silver catfish larvae was observed at water with 20.26 mg.L-1 Ca2+ and 2.89 mg.L-1 Mg2+, with similar results to the group exposed to water hardness of 20 mg.L-1 CaCO3. However, compared to the group exposed to water hardness of 20 mg.L-1 CaCO3, survival and growth were lower at 150 mg.L-1 CaCO3. Therefore, a hardness range of 20 to 70 mg.L-1 CaCO3 is recommended for silver catfish larviculture, but with 20.26 mg.L-1 Ca2+ and 2.89 mg.L-1 Mg2+ at 70 mg.L-1 CaCO3. Water hardness of 150 mg.L-1 CaCO3 is not recommended for this species.

  18. New Dancing Couple: PD-L1 and MicroRNA.

    Science.gov (United States)

    Grenda, A; Krawczyk, P

    2017-09-01

    Lung cancer (LC) is the most common cause of cancer death in the world. A great challenge in treating NSCLC is the discovery of advanced, molecular tools to diagnose the disease in early stages as well as the development of immunotherapy. MicroRNAs are regulatory molecules (~20 nt in length) with the ability to regulate the expression of genes. The recently described PD-1 and PD-L1 molecules have great importance for potential use in immunotherapy of many cancers. These molecules are associated with immune checkpoints and provide an opportunity for the treatment of advanced NSCLC patients with synthetic monoclonal antibodies. PD-L1 expression is strictly associated with microRNA function in lung cancer cells. The group of microRNAs related to PD-L1 includes, among others, miR-200, miR-197 or miRNA-34. Expression of these molecules may be useful in lung cancer diagnosis, qualification to anti-PD-1 or anti-PD-L1 antibody therapy and could be a potential therapeutic target. However, studies on PD-L1-related microRNAs are necessary to develop advanced targeted molecular therapies. © 2017 The Foundation for the Scandinavian Journal of Immunology.

  19. Acanthocephala Larvae parasitizing Ameiva ameiva ameiva (Linnaeus, 1758) (Squamata: Teiidae).

    Science.gov (United States)

    Macedo, Lilian Cristina; Melo, Francisco Tiago de Vasconcelos; Ávila-Pires, Teresa Cristina Sauer; Giese, Elane Guerreiro; Santos, Jeannie Nascimento Dos

    2016-03-11

    Knowledge concerning the taxonomy and biology of species of Acanthocephala, helminth parasites of the helminth species of the phylum Acanthocephala, parasites of lizards in Brazilian Amazonia, is still insufficient, but reports of Acanthocephala in reptiles are becoming increasingly common in the literature. Cystacanth-stage Acanthocephalan larvae have been found in the visceral peritoneum during necropsy of Ameiva ameiva ameivalizards from the "Osvaldo Rodrigues da Cunha" Herpetology Collection of the Emílio Goeldi Museum, Belém, Pará, Brazil. The aim of this study was to present the morphological study of the Acanthocephala larvae found in A. ameiva ameiva lizard.

  20. Do L1 Reading Achievement and L1 Print Exposure Contribute to the Prediction of L2 Proficiency?

    Science.gov (United States)

    Sparks, Richard L.; Patton, Jon; Ganschow, Leonore; Humbach, Nancy

    2012-01-01

    The study examined whether individual differences in high school first language (L1) reading achievement and print exposure would account for unique variance in second language (L2) written (word decoding, spelling, writing, reading comprehension) and oral (listening/speaking) proficiency after adjusting for the effects of early L1 literacy and…

  1. Predatory efficiency of the sewage drain inhabiting larvae of Toxorhynchites splendens Wiedemann on Culex quinquefasciatus Say and Armigeres subalbatus (Coquillett) larvae.

    Science.gov (United States)

    Aditya, Gautam; Bhattacharyya, Sankar; Kundu, Niloy; Kar, Pradip Kumar; Saha, Goutam Kumar

    2007-09-01

    The rate of predation by stage IV instar Toxorhynchites splendens larvae on the equivalent instar stage larvae of Culex quinquefasciatus and Armigeres subalbatus, co-occurring in sewage drains, were noted for a period of three consecutive days in the laboratory using different prey densities and combinations. The rate of predation varied by age of the predator, density of prey, and prey type. The number of Ar. subalbatus larvae consumed by a single Tx. splendens larva ranged between 0.50 +/- 0.71 and 16.40 +/- 2.01; while for Cx. quinquefasciatus larvae, the number consumed ranged from 0.20 +/- 0.42 to 20.40 +/- 1.43 per day. The pupation rates of the prey species varied in respect to control, with a minimum of 0.20 +/- 0.42 pupa/day to a maximum of 12.20 +/- 2.30 pupa/day in the presence of Tx. splendens. The values for the controls were 1.00 +/- 0.87 and 14.44 +/- 2.83 pupa/day, respectively. Irrespective of prey densities and combinations, a single Tx. splendens fourth instar larvae was found to consume on average 10.07 larvae on the first day 16.57 larvae on the second day and 4.38 larvae on the third day, killing a total of 17.70 to 45.10 larvae, in three days. In the presence of Tx. splendens, the cumulative pupation, irrespective of prey, remained between 12.20 and 45.10, and differed significantly from control where the values were between 13.90 and 54.70. The results indicate that Tx. splendens can significantly reduce immature numbers and lower the rate of pupation of Cx. quinquefasciatus and Ar. subalbatus. Tx. splendens may be a potential biological resource in the control of mosquitoes inhabiting sewage drains.

  2. L1CAM expression associates with poor outcome in endometrioid, but not in clear cell ovarian carcinoma.

    Science.gov (United States)

    Soovares, Piret; Pasanen, Annukka; Bützow, Ralf; Lassus, Heini

    2017-09-01

    Our aim was to study the expression of L1CAM in endometrioid and clear cell ovarian carcinomas and to evaluate its correlation with clinical parameters and patient prognosis. Tissue microarray -based immunohistochemical analysis of L1CAM expression was performed in 249 endometrioid and 140 clear cell ovarian carcinomas. Concurrent endometrial carcinoma was found in 57 of these patients. L1CAM expression was found in 15% of endometrioid and 23% of clear cell ovarian carcinomas. L1CAM expression was strongly associated with poor disease-specific overall survival and poor disease-free survival in endometrioid (povarian carcinomas. Significant association of L1CAM expression with poor overall survival was observed in grade 1-2 carcinomas (povarian carcinomas, L1CAM expression was associated with aggressive tumor characteristics, such as higher grade and stage, and incomplete response to primary therapy. However, L1CAM expression was not an independent prognostic factor for overall or disease-free survival. Of the 57 patients with concurrent endometrial carcinoma L1CAM positivity was found in 4 cases both in the ovarian and endometrial tumors, and in 3 cases only in the endometrial tumor. All these seven patients with L1CAM positive tumors had poor outcome. L1CAM expression could serve as a biomarker for predicting clinical outcome and response to therapy in patients with endometrioid ovarian carcinoma, but not in clear cell carcinomas. L1CAM positivity also predicts poor outcome in patients with concurrent endometrioid ovarian and endometrial carcinomas. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Experimental culture of the river prawn Macrobrachium americanum larvae (Bate, 1868, with emphasis on feeding and stocking density effect on survival

    Directory of Open Access Journals (Sweden)

    Stig Yamasaki-Granados

    2013-09-01

    Full Text Available The cauque river prawn Macrobrachium americanum occurs along the Pacific coast of America. This prawn can grow to a large size, making it an interesting option for aquaculture production. Currently, supplies of juveniles are limited because hatchery and laboratory-reared larvae are difficult to raise. This study assesses larval survival for different combinations of stocking density and feeding from larvae cultivated in green water. From these combinations, larvae fed with Artemia nauplii and maintained at a density of 50 larvae L-1 had the highest survival.

  4. Production and characterization of a monoclonal antibody against recombinant cathepsin L1 of Fasciola gigantica.

    Science.gov (United States)

    Anuracpreeda, Panat; Srirakam, Thippawan; Pandonlan, Sudarat; Changklungmoa, Narin; Chotwiwatthanakun, Charoonroj; Tinikul, Yotsawan; Poljaroen, Jaruwan; Meemon, Krai; Sobhon, Prasert

    2014-08-01

    Monoclonal antibodies (MoAbs) against a recombinant cathepsin L1 of Fasciola gigantica (rFgCatL1) were produced in vitro by fusion of BALB/c mice spleen cells immunized with rFgCatL1 and mouse myeloma cells. Reactivity and specificity of these MoAbs were evaluated by indirect ELISA and immunoblotting techniques. Seven MoAb clones were selected from the stable hybridoma clones, namely 1E10, 1F5, 3D11, 4B10, 4D3, 4E3 and 5E7. Clones 1E10, 1F5 and 3D11 were IgM, whereas clones 4B10, 4D3, 4E3 and 5E7 were IgG1. All MoAbs had kappa light chain isotypes. All MoAbs reacted with rCatL1 at molecular weight (MW) 30kDa and with the native CatL1 at MW 27kDa in whole body (WB) extracts of metacercariae (Met), newly excysted juveniles (NEJ), 1, 3, 5-week-old juveniles (Ju), adult WB and adult excretory-secretory (ES) fractions, but not with adult tegumental antigens (TA). All of these MoAbs showed no cross-reactions with antigens of other parasites commonly found in ruminants and human, including Paramphistomum cervi, Eurytrema pancreaticum, Gigantocotyle explanatum, Schistosoma spindale, Schistosoma mansoni, Moniezia benedeni, Avitellina centripunctata, Trichuris sp., Haemonchus placei and Setaria labiato-papillosa. Localization of CatL1 in each developmental stages of F. gigantica by immunoperoxidase technique, using these MoAbs as probes, indicated that CatL1 was present at high concentration in the caecal epithelium and caecal lumen of metacercariae, NEJ, 1, 3, 5-week-old juveniles and adult fluke. This finding indicated that CatL1 is a copiously expressed parasite protein that is released into the ES, thus CatL1 and its MoAb could be a good candidate for immunodiagnosis of fasciolosis in ruminant and human. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Cold hardiness and supercooling capacity in the overwintering larvae of the codling moth, Cydia pomonella.

    Science.gov (United States)

    Khani, Abbas; Moharramipour, Saeid

    2010-01-01

    The codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), a worldwide apple pest, is classified as a freeze-intolerant organism and one of the most cold-tolerant pests. The objectives of this study were to examine the supercooling point of overwintering and non-diapausing larvae of C. pomonella as an index of its cold hardiness, and to assess larval mortality following 24 h exposure to extreme low temperatures ranging from -5 to -25 degrees C. The mean (+/-SE) supercooling point for feeding larvae (third through fifth instars) was -12.4 +/- 1.1 degrees C. The mean supercooling point for cocooned, non-diapausing larvae (i.e., non-feeding stages) decreased as the days that the arvae were cocooned increased and changed between -15.1 +/- 1.2 degrees C for one to two day cocooned arvae and -19.2 +/- 1.8 degrees C for less than five day cocooned larvae. The mean (+/-SE) supercooling point for other non-feeding stages containing pupae and overwintering larvae were -19.9 +/- 1.0 degrees C and -20.2 +/- 0.2 degrees C, respectively. Mean supercooling points of C. pomonella larvae were significantly lower during the winter months than the summer months, and sex had no effect on the supercooling point of C. pomonella larvae. The mortality of larvae increased significantly after individuals were exposed to temperatures below the mean supercooling point of the population. The supercooling point was a good predictor of cold hardiness.

  6. Dimethyl Sulfide is a Chemical Attractant for Reef Fish Larvae.

    Science.gov (United States)

    Foretich, Matthew A; Paris, Claire B; Grosell, Martin; Stieglitz, John D; Benetti, Daniel D

    2017-05-31

    Transport of coral reef fish larvae is driven by advection in ocean currents and larval swimming. However, for swimming to be advantageous, larvae must use external stimuli as guides. One potential stimulus is "odor" emanating from settlement sites (e.g., coral reefs), signaling the upstream location of desirable settlement habitat. However, specific chemicals used by fish larvae have not been identified. Dimethyl sulfide (DMS) is produced in large quantities at coral reefs and may be important in larval orientation. In this study, a choice-chamber (shuttle box) was used to assess preference of 28 pre-settlement stage larvae from reef fish species for seawater with DMS. Swimming behavior was examined by video-tracking of larval swimming patterns in control and DMS seawater. We found common responses to DMS across reef fish taxa - a preference for water with DMS and change in swimming behavior - reflecting a switch to "exploratory behavior". An open water species displayed no response to DMS. Affinity for and swimming response to DMS would allow a fish larva to locate its source and enhance its ability to find settlement habitat. Moreover, it may help them locate prey accumulating in fronts, eddies, and thin layers, where DMS is also produced.

  7. Microplastic ingestion in fish larvae in the western English Channel.

    Science.gov (United States)

    Steer, Madeleine; Cole, Matthew; Thompson, Richard C; Lindeque, Penelope K

    2017-07-01

    Microplastics have been documented in marine environments worldwide, where they pose a potential risk to biota. Environmental interactions between microplastics and lower trophic organisms are poorly understood. Coastal shelf seas are rich in productivity but also experience high levels of microplastic pollution. In these habitats, fish have an important ecological and economic role. In their early life stages, planktonic fish larvae are vulnerable to pollution, environmental stress and predation. Here we assess the occurrence of microplastic ingestion in wild fish larvae. Fish larvae and water samples were taken across three sites (10, 19 and 35 km from shore) in the western English Channel from April to June 2016. We identified 2.9% of fish larvae (n = 347) had ingested microplastics, of which 66% were blue fibres; ingested microfibers closely resembled those identified within water samples. With distance from the coast, larval fish density increased significantly (P microplastic concentrations (P microplastics and the incidence of ingestion in fish larvae. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The use of morphological and histological features as nutritional condition indices of Pagrus pagrus larvae

    Directory of Open Access Journals (Sweden)

    Marina Vera Diaz

    Full Text Available Morphometrical and histological techniques were employed to characterize Pagrus pagrus larvae nutritional condition. Larvae were reared in laboratory under controlled conditions with the main objective of testing whether these methodologies allowed finding differences between larvae from different feeding treatments. Once yolk was consumed (three days after hatching larvae were assigned to a feeding treatment: starved during the whole experiment; delayed feeding, starved during three days; fed during the entire experiment. Algae (Nannochloropsis oculata and rotifers (Brachionus plicatilis were provided to larvae for feed treatments. Larvae were fixed daily; for morphometrical purposes in 5% formaldehyde solution, and in Bouin for histological sections. Results herein obtained showed that both methodologies are sensitive enough to distinguish larvae characterized by different nutritional condition states obtained from the feeding treatments. Consequently, these methodologies could be employed in wild red porgy larvae in order to asses their nutritional condition. These techniques could also be employed to check larval quality obtained with aquaculture purposes to estimate the effects of changes in rearing protocols or kind of food supply and thus, to guaranty a higher survival of early developmental stages of reared larvae.

  9. Effects of clay turbidity and density of pikeperch (Sander lucioperca) larvae on predation by perch (Perca fluviatilis).

    Science.gov (United States)

    Pekcan-Hekim, Zeynep; Lappalainen, Jyrki

    2006-07-01

    Increased turbidity reduces visibility in the water column, which can negatively affect vision-oriented fish and their ability to detect prey. Young fish could consequently benefit from high turbidity levels that can provide a protective cover, reducing predation pressure. Perch (Perca fluviatilis) are commonly found in littoral zones of temperate lakes and coastal areas of the Baltic Sea. Pikeperch (Sander lucioperca) spawn in these areas, so perch is a potential predator for pikeperch larvae. We conducted laboratory experiments to test the predation of perch on pikeperch larvae at different turbidity levels (5-85 nephelometric turbidity units), densities of pikeperch larvae (2-21 individuals l(-1)) and volumes of water (10-45 l). The logistic regression showed that the probability of larvae eaten depended significantly on turbidity and volume of water in the bags, while density of larvae was not significant. However, because container size is known to affect predation, the data was divided into two groups based on water volume (10-20 and 25-45 l) to reduce the effects of container size. In either group, probability of predation did not significantly depend on volume, whereas turbidity was significant in both groups, while density was significant in larger water volumes. Thus, high turbidity impaired perch predation and protected pikeperch larvae from perch predation. Because density of larvae was also a significant factor affecting predation of perch, the dispersal of pikeperch larvae from spawning areas should also increase the survival of larvae.

  10. Desiccation resistance of Chironomid larvae

    Directory of Open Access Journals (Sweden)

    Jan Frouz

    2015-07-01

    Full Text Available Resistance to desiccation in larvae of eight species of aquatic, semiaquatic and terrestrial chironomids (Pseudodiamesa branickii, Macropelopia sp., Prodiamesa olivacea, Micropsectra sp., Chironomus riparius, Chironomus dorsalis, Metriocnemus martini and Camptocladius stercorarius was studied. The larvae were desiccated in exicator at constant conditions (15 °C, 80% RH and changes in moisture and body water content was recorded. The LD-50 for loss of body water was calculated. The lowest resistance to loss of body water was found in larvae from subfamilies Tanypodinae and Diamesinae Macropelopia sp. and P. branickii. They survived loss of 49.7 and 56.6% of original water content (presented values are LD-50. On the other hand the highest resistance to water loss was found in C. dorsalis. M. martini and C. stercorarius. The larvae of these species may survive loss of 67.4, 76.6 and 84.2% of original water content. Nevertheless the survival time under experimental conditions depends more closely on larval size than on lethal level of water loss. The smaller larvae desiccated faster and perished sooner than large ones despite they tolerate higher loss of body water.

  11. Lidar In-Space Technology Experiment (LITE) L1

    Data.gov (United States)

    National Aeronautics and Space Administration — LITE_L1 data are LIDAR Vertical profile data along the orbital flight path of STS-64.Lidar In-Space Technology Experiment (LITE) used a three-wavelength (355 nm, 532...

  12. IceBridge Atmospheric Chemistry L1B Data

    Data.gov (United States)

    National Aeronautics and Space Administration — The IceBridge Atmospheric Chemistry L1B Data set (ICHEM1B) contains measurements acquired over Antarctica using the AVOCET differential Non-Dispersive Infrared...

  13. Research into communication between L1DDC and FELIX

    CERN Document Server

    Keser, Marceline

    2016-01-01

    This report describes the summer student project of Marceline Keser, performed with the team for the New Small Wheel electronics upgrade of ATLAS. The main goal of the project is to create communication between the FELIX and L1DDC, in order to create a bidirectional data transmission. During this project, research has been done and has resulted in a GBT link between the L1DDC and FELIX.

  14. Bregman Distance to L1 Regularized Logistic Regression

    OpenAIRE

    Gupta, Mithun Das; Huang, Thomas S.

    2010-01-01

    In this work we investigate the relationship between Bregman distances and regularized Logistic Regression model. We present a detailed study of Bregman Distance minimization, a family of generalized entropy measures associated with convex functions. We convert the L1-regularized logistic regression into this more general framework and propose a primal-dual method based algorithm for learning the parameters. We pose L1-regularized logistic regression into Bregman distance minimization and the...

  15. Learners’ L1 Use in a Task-based Classroom

    DEFF Research Database (Denmark)

    Bao, Rui; Du, Xiangyun

    2015-01-01

    In the past two decades, strong theoretical and pedagogical arguments have been made advocating for task-based activities in the language-learning context. However, many teachers have been reluctant to in- corporate task-based activities into their teaching practices due to concerns about learners......, but with only a very small amount oc- curring for off-task talk across tasks. L1 use mainly occurred in learners’ efforts to mediate completion of the tasks. The findings highlight the role of L1 in foreign language learning and suggest that L1 use is associated with a number of factors, such as task types......’ extensive L1 use and off-task talk. Informed by sociocultural theory, this study explored the extent to which L1s and their func- tions were used when performing tasks. The subjects were beginner-level lower-secondary school learners of Chinese. The data shows that learners have a high amount of L1 use...

  16. The Pleiotropic Role of L1CAM in Tumor Vasculature

    Directory of Open Access Journals (Sweden)

    Francesca Angiolini

    2017-01-01

    Full Text Available Angiogenesis, the formation of new vessels, is a key step in the development, invasion, and dissemination of solid tumors and, therefore, represents a viable target in the context of antitumor therapy. Indeed, antiangiogenic approaches have given promising results in preclinical models and entered the clinical practice. However, in patients, the results obtained so far with antiangiogenic drugs have not completely fulfilled expectations, especially because their effect has been transient with tumors developing resistance and evasion mechanisms. A better understanding of the mechanisms that underlie tumor vascularization and the functional regulation of cancer vessels is a prerequisite for the development of novel and alternative antiangiogenic treatments. The L1 cell adhesion molecule (L1CAM, a cell surface glycoprotein previously implicated in the development and plasticity of the nervous system, is aberrantly expressed in the vasculature of various cancer types. L1CAM plays multiple pro-angiogenic roles in the endothelial cells of tumor-associated vessels, thus emerging as a potential therapeutic target. In addition, L1CAM prevents the maturation of cancer vasculature and its inhibition promotes vessel normalization, a process that is thought to improve the therapeutic response of tumors to cytotoxic drugs. We here provide an overview on tumor angiogenesis and antiangiogenic therapies and summarize the current knowledge on the biological role of L1CAM in cancer vasculature. Finally, we highlight the clinical implications of targeting L1CAM as a novel antiangiogenic and vessel-normalizing approach.

  17. Hepatic arginase activity in intra- and extrauterine larvae of the ovoviviparous salamander. Salamandra salamandra (L.) (Amphibia, Urodela).

    Science.gov (United States)

    Schindelmeiser, J; Schindelmeiser, I; Greven, H

    1983-01-01

    The hepatic arginase activity of Salamandra salamandra was determined at three different stages of intra- and extrauterine larval development and at fully metamorphosed juveniles. The highest enzymatic activity was found in intrauterine larvae in November, the lowest in intrauterine larvae in June of the following year. These data can be correlated with the ureotelism of intrauterine larvae previously described and are discussed with respect to the metabolism of larval and juvenile fire salamanders.

  18. Reduction of Escherichia coli, Salmonella Enteritidis and Campylobacter jejuni in poultry manure by rearing of Musca domestica fly larvae

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Fischer, C.; Bjerrum, L.

    2017-01-01

    A major barrier for using animal waste as substrate for production of insects for feed or food is the concern for safety of the end products. In this study we investigated how rearing of fly larvae of Musca domestica in poultry manure influenced the counts of three pathogenic test strains...... of the larvae stage. This study provides data for evaluation of feed safety of fly larvae reared on animal waste. Furthermore suggests a potential use for reduction of these pathogens in manure....

  19. Retrospective Molecular Epidemiology Study of PD-L1 Expression in Patients withEGFR-Mutant Non-small Cell Lung Cancer.

    Science.gov (United States)

    Cho, Jong Ho; Zhou, Wei; Choi, Yoon-La; Sun, Jong-Mu; Choi, Hyejoo; Kim, Tae-Eun; Dolled-Filhart, Marisa; Emancipator, Kenneth; Rutkowski, Mary Anne; Kim, Jhingook

    2018-01-01

    Data are limited on programmed death ligand 1 (PD-L1) expression in epidermal growth factor receptor ( EGFR )-mutant non-small cell lung cancer (NSCLC). We retrospectively evaluated the relationship between PD-L1 expression and recurrence-free survival (RFS) and overall survival in 319 patients with EGFR -mutant NSCLC who were treated at Samsung Medical Center from 2006 to 2014. Membranous PD-L1 expression on tumor cells was measured using the PD-L1 IHC 22C3 pharmDx antibody and reported as tumor proportion score (TPS). Kaplan-Meier methods, log-rank test, and Cox proportional hazards models were used for survival analysis. All patients had ≥1 EGFR mutation-54% in exon 19 and 39% in exon 21. Overall, 51% of patients had PD-L1-positive tumors. The prevalence of PD-L1 positivity was higher among patients with stages II-IV versus stage I disease (64% vs. 44%) and among patients with other EGFR mutations (75%) than with L858R mutation (39%) or exon 19 deletion (52%). PD-L1 positivity was associated with shorter RFS, with an adjusted hazard ratio of 1.52 (95% confidence interval [CI], 0.81 to 2.84; median, 18 months) for the PD-L1 TPS ≥ 50% group, 1.51 (95% CI, 1.02 to 2.21; median, 31 months) for the PD-L1 TPS 1%-49% group, and 1.51 (95% CI, 1.05 to 2.18) for the combined PD-L1-positive groups (TPS ≥ 1%) compared with the PD-L1-negative group (median, 35 months). PD-L1 expression is associated with disease stage and type of EGFR mutation. PD-L1 positivity might be associated with worse RFS among patients with surgically treated EGFR -mutant NSCLC.

  20. Abundancia y distribución de larvas de Strombus gigas (Mesogastropoda: Strombidae durante el período reproductivo de la especie en el Caribe Mexicano Abundance and distribution of Strombus gigas (Mesogastropoda: Strombidae larvae during their reproductive period in the Mexican Caribbean

    Directory of Open Access Journals (Sweden)

    José Francisco Chávez Villegas

    2012-03-01

    C, salinity (ppm and dissolved oxygen (mg L-1 were recorded for each site. A mean larval density of 0.34±0.87 (larvae 10 m-3 was registered between locations, with a peak in August and September (0.82±1.00 and 0.76±1.68 larvae 10m-3, respectively. The larval density was 60% correlated with salinity (r=0.6063, p0.05. A 100% of the captured larvae correspond to stage I, showing local reproductive activity, that might indicate the sampled sites in the MC are a source of larvae to S. gigas. Rev. Biol. Trop. 60 (Suppl. 1: 89-97. Epub 2012 March 01.

  1. Aluminium chloride-induced toxicity in zebrafish larvae.

    Science.gov (United States)

    Monaco, A; Grimaldi, M C; Ferrandino, I

    2017-05-01

    Embryos at shield stage and larvae at protruding mouth stage were exposed to different concentrations of aluminium chloride (AlCl 3 ) for 72 h with the purpose to analyse their phenotype and lethality. After 24, 48 and 72 h of treatment, higher toxicity of the metal was observed on larvae with minimal lethal concentration of 0.25, 0.20 and 0.08 mm, respectively, while for embryos the corresponding values were 40, 25 and 16 mm. We observed pericardial oedema and alteration of heart rate in 50% of larvae after 48 h of exposure to 100 μm. In larvae exposed to the same concentration, there was also a neurological injury at the level of glial cells, with the number of glial fibrillary acidic protein-positive cells being significantly reduced. This study confirms the toxic nature of this metal and shows that aluminium could also interestingly represent a cardiotoxin in addition to its neurotoxic ability. © 2016 John Wiley & Sons Ltd.

  2. Characterization of the excretory/secretory products of Dermatobia hominis larvae, the human bot fly.

    Science.gov (United States)

    Brant, M P R; Guimarães, S; Souza-Neto, J A; Ribolla, P E M; Oliveira-Sequeira, T C G

    2010-03-25

    Proteolytic activity in excretory/secretory products (ESP) of first- (L1), second- (L2) and third-instar (L3) larvae of Dermatobia hominis was analyzed through gelatin-gel and colorimetric enzyme assays with the chromogenic substrates azocasein and BApNA. The functional characterization of proteases was based on inhibition assays including synthetic inhibitors. ESP were obtained from new-hatched larvae reared in the laboratory and from second- and third-instar larvae removed from naturally infested cattle. Gelatin-gel analysis evidenced few bands of proteolysis, predominantly of high apparent molecular masses, in ESP of L1, whereas in the gel of L2 and L3 ESP there was a wide range of proteolytic activity most of them not resolved in a single species. Azocasein assays revealed a progressive increase of protease activity from first- to third-instar larvae. Protease inhibitor assays revealed a predominance of metalloproteases in L1 ESP that could be related to a skin penetration process and to a diversion of host immune response. The predominance of serine proteases in L2 and L3 and the great tryptic activity presented by L3 ESP were attributed to an increasing trophic activity by the growing larvae, since the viability of adult flies strictly depends on larval abilities to assimilate nutrients from the host. Taking together, these results suggest that Dematobia larvae secrete/excrete different proteases that may be related to diverse functions during host penetration and infestation, which reinforces the relevance of the study of such proteolytic enzymes.

  3. PD-L1 Status in Refractory Lymphomas.

    Directory of Open Access Journals (Sweden)

    Semir Vranic

    Full Text Available Targeted immunotherapy based on PD-1/PD-L1 suppression has revolutionized the treatment of various solid tumors. A remarkable improvement has also been observed in the treatment of patients with refractory/relapsing classical Hodgkin lymphoma (cHL. We investigated PD-L1 status in a variety of treatment resistant lymphomas. Tumor samples from 78 patients with therapy resistant lymphomas were immunohistochemically (IHC investigated for the expression of PD-L1 using two antibody clones (SP142 and SP263, Ventana. Thirteen PD-L1+ cases were further analyzed for gene copy number variations (CNV by NGS and for PD-L1/JAK2/PD-L2 co-amplification using fluorescent in-situ hybridization assay (FISH. PD-L1 positivity (≥5% positive cancer cells, IHC was present in 32/77 (42% and 33/71 cases (46% using SP142 and SP263 antibodies, respectively. Concordance between the two anti-PD-L1 clones was high with only three (4% discrepant cases. The strongest and consistent (10/11 cases expression was observed in cHL and primary mediastinal B-cell lymphomas (3/3. Diffuse large B-cell lymphomas (DLBCL were frequently positive (13/26 irrespective of subtype. Follicular (1/8, peripheral T-cell (3/11 and mantle cell (1/8 lymphomas were rarely positive, while small lymphocytic lymphoma/CLL and marginal zone lymphomas were consistently negative (3/3. Co-amplification/CNVs of PD-L1/JAK2/PD-L2 were observed in 3 cases of DLBCL and cHL, respectively. Of note, all three cHL-amplified cases were positive by FISH, but not by NGS. Since only a fraction of the IHC positive lymphoma cases were positive by FISH and NGS assays, other mechanisms are involved in PD-L1 upregulation, especially in DLBCL. FISH assay may be more suitable than NGS assay for determination of PD-L1 alterations in cHL.

  4. Resistance to OsHV-1 infection in Crassostrea gigas larvae

    Directory of Open Access Journals (Sweden)

    Lionel eDégremont

    2016-02-01

    Full Text Available The ostreid herpesvirus (OsHV-1 is one of the major diseases that affect the Pacific oyster Crassostrea gigas. Selective breeding programs were recently shown to improve resistance easily to OsHV-1 infections in spat, juvenile and adult oysters. Nevertheless, this resistance has never been investigated in larvae, whereas this developmental stage has crucial importance for the production of commercial hatcheries, as well as explaining the abundance of spatfall. A first trial tested several viral suspensions at several concentrations using contaminated water with OsHV-1 in four-day-old and ten-day-old larvae that were produced from an unselected broodstock. In follow up on the results, one viral suspension at a final concentration of 10+6 OsHV-1 DNA copies per L was used to assess resistance to OsHV-1 infection in C. gigas larvae that were produced from selected and unselected broodstock. A second trial evaluated OsHV-1 resistance in larvae from both broodstocks in trials 2a, 2b and 2c with 4, 10 and 16-day-old larvae for 7 days, which corresponded to post D larvae, umbo larvae and eyed larvae, respectively. The mortality of unchallenged larvae for both stocks were low (<15% at day 7 in trials 2a and 2b, whereas it ranged from 48 to 56% in trial 2c. More interestingly, selected larvae had significantly lower mortality than unselected larvae when exposed to OsHV-1 in all of the trials. Thus, the mortality was 11% and 49% for the selected larvae at day 7 post-exposure in trials 2a and 2c, respectively, in comparison with 84% and 97% for the unselected larvae. Although this difference in mortality was observed at day 5 in trial 2b, it was reduced at day 7, to 86% and 98% for the selected and unselected larvae, respectively. For the first time in the literature, the difference in mortality or the delayed onset of mortality between selected and unselected larvae have indicated a genetic resistance to OsHV-1 infection at the larval stage. Such finding

  5. Preliminary Results On the Efficacy of Macroalgal Extracts Against Larvae of Aedes albopictus.

    Science.gov (United States)

    Minicante, Simona Armeli; Carlin, Sara; Stocco, Marica; Sfriso, Adriano; Capelli, Gioia; Montarsi, Fabrizio

    2017-12-01

    Activity of ethanolic extracts of the algae Ulva rigida, Asparagopsis taxiformis, Dictyota dichotoma, and Cystoseira barbata, collected along Italian coasts, was tested against larvae of the Asian tiger mosquito ( Aedes albopictus), a vector of pathogens for animals and humans. Tests were carried out using 10 specimens of 3rd-stage larvae per test, following the World Health Organization standard protocol with minor modifications. Among algal extracts, only D. dichotoma was active against the larvae of Ae. albopictus. Ethanolic extracts of that species showed LC 90 (the concentration that kills 90% of larvae) and LC 50 (the concentration that kills 50% of larvae) values at 44.32 and 85.92 mg/liter, respectively. Based on the data obtained, D. dichotoma biometabolic extracts could be potential candidates as larvicide compounds to control Ae. albopictus, encouraging the use of macroalgae as natural resources in integrated vector management strategies.

  6. Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

    Directory of Open Access Journals (Sweden)

    Sacchi L.

    2001-06-01

    Full Text Available The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear, T. spiralis (horses and humans, T. pseudospiralis (a laboratory mouse and T. papuae (a laboratory mouse were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

  7. Efficiency of eugenol as anesthetic for the early life stages of Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Paula A.P. Ribeiro

    2015-03-01

    Full Text Available In aquaculture, activities with anesthetic compounds are usually used in order to ensure the welfare of farmed fish, allowing handling out of water with decreased trauma by stress. Presently, there is no information about anesthetic action of eugenol in early life stages of Nile tilapia (Oreochromis niloticus. The objective of this study was to evaluate different concentrations of eugenol for larvae and juveniles of Nile tilapia. Sixty animals were used for each group of weight, group I = 0.02 g; group II = 0.08 g; group III = 0.22 g; group IV = 2.62 g; and group V = 11.64 g. The eugenol concentrations tested were 50, 75, 100, 125, 150 and 175 mg L-1. No mortality was reported during the tests with eugenol. Tilapia larvae with 0.02 g and juveniles around 11.64 g can be anesthetized with eugenol concentrations between 150 and 175 mg L-1, since they determine the shortest sedation time (23 and 72 seconds, for the group of lowest and highest weights, respectively.

  8. icacy test of hexane extract of Annona squamosa L seeds for Chrysomya bezziana larvae growth in vitro

    Directory of Open Access Journals (Sweden)

    April H Wardhana

    2004-12-01

    Full Text Available Chrysomya bezziana is primer agent causing myiasis in livestock and human throughout Africa to Asia. At present, treatment of myiasis using chemical synthetic insecticide causing environment and livestock production contaminations. The aim of this study was to evaluate the effect of hexane extract of Annona squamosa L seed to kill C. bezziana as botanical insecticide. Three level and method preparation of larvae (L1, L2 and L3 were carried out. Meat blood mixture (MBM and larval rearing media (LRM were mixed with hexane extract of A. squamosa L seed and tested to 625 and 750 larvae (L1and L2 respectively, while for L3 625 larvae were soaked in the solution containing the hexane extract. This last preparation was carried out to observe the effect of toxic contact. Each larvae treatment was divided into 5 levels such as negative control using distillation water (PO, given 0.25% hexane extract (P I; 0.50% (P II; 0.75% (P III and positive control was given with 0.10% Asuntol®. This assay was to know digest toxic effect of hexane extract of A. squamosa L seed for those larvae. Number of 625 instar III larvae (L3 was soaked in the solution containing the hexane extract of A. squamosa L seed for 10 second, placed into vermicullite and incubated on 36oC. This assay was to know contact toxic effect of them. All of larvae were allowed to become pupae. Parameters oberserve were number of larvae death, pupae weight and number of pupae become into fly. The data was analyzed using Anova (5% and Z test (5% then smallest significant difference test (BNT 5%. The results showed that 0.50% of hexane extract of A. squamosa L seed was able to decrease pupae weight for L1 and L2 and to cause fail pupae become fly (P0.05.

  9. [Biotechnological aspects in "loco" larvae].

    Science.gov (United States)

    Inestrosa, N C; Labarca, R; Perelman, A; Campos, E O; Araneda, R; González, M; Brandan, E; Sánchez, J P; González-Plaza, R

    1990-10-01

    The biology of planktotrophic larvae of Concholepas concholepas is the main bottleneck towards developing biotechnologies to rear this muricid. Data concerning planktonic larvae development, diets and environmental signals triggering larval settlement and recruitment is scarce. We have begun the study of the molecular and cell biology of embryos, larvae and recruits having as a final goal, the development of appropriate biotechnologies to rear this gastropod. First, an inverse ratio between BuChE and AChE enzyme activities was established. This ratio may be a precise developmental marker for this species. Second, for the first time a phosphoinositide related regulatory pathway is reported in a muricid, opening a new approach to the biotechnological management of larvae. Third, the relation between sulfate in sea water and larval motility was studied. Concentrations below 125 microM sulfate decreases larval motility. The sulfate is incorporated in proteoglycans which participate in different developmental phenomena. Lastly, a genomic Concholepas concholepas DNA sequence, similar to that of a human growth hormone probe was detected. This is very interesting since growth factors are key molecules during development, growth and are involved in food conversion rates in fish and also, in a variety of marine invertebrates.

  10. Reorientation and Swimming Stability in Sea Urchin Larvae

    Science.gov (United States)

    Wheeler, J.; Chan, K. Y. K.; Anderson, E.; Helfrich, K. R.; Mullineaux, L. S.; Sengupta, A.; Stocker, R.

    2016-02-01

    Many benthic marine invertebrates have two-phase life histories, relying on planktonic larval stages for dispersal and exchange of individuals between adult populations. The dispersal of planktonic larvae is determined by two factors: passive advection by the ambient flow and active motility. By modifying dispersal and ultimately settlement, larval motility influences where and when individuals recruit into benthic communities. Despite its ecological relevance, our understanding of larval motility and behavior in the plankton remains limited, especially regarding the interactions of larval motility and ambient turbulence. As most larvae are smaller than the Kolmogorov scale, they experience ocean turbulence in part as a time-changing viscous torque produced by local fluid shear. This torque causes larval reorientation, impacting swimming direction and potentially dispersal at the macroscale. It is therefore paramount to understand the mechanisms of larval reorientation and the stability of larvae against reorientation. Here we report on the larval reorientation behavior of the sea urchins Arbacia punctulata and Heliocidaris crassispina. Both species have life histories characterized by ontogenetic changes to internal density structure and morphology, which we hypothesized to impact stability. To test this hypothesis, we performed "flip chamber" experiments, in which larvae swim freely in a small chamber that is intermittently inverted, mimicking the overturning experienced by larvae in turbulence. We investigated the role of larval age, body size, species, morphology (number of arms), and motility (live versus dead) on the reorientation dynamics. Our work contributes to a more mechanistic understanding of the role of hydrodynamics in the motility and transport of planktonic larvae.

  11. The morphology of the immature stages of two rare Lixus species (Coleoptera, Curculionidae, Lixinae) and notes on their biology

    OpenAIRE

    Trnka,Filip; Stejskal,Robert; Skuhrovec,Jiří

    2016-01-01

    Abstract The mature larvae and pupae of Lixus (Ortholixus) bituberculatus Smreczy?ski, 1968 and Lixus (Dilixellus) neglectus Fremuth, 1983 ( Curculionidae : Lixinae : Lixini ) are described and compared with known larvae of 21 other Lixus and 2 Hypolixus taxa. The mature larva and pupa of Lixus bituberculatus are the first immature stages described representing the subgenus Ortholixus . The larva of Lixus neglectus , in the subgenus Dilixellus , is distinguished from the known larvae of four ...

  12. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    Science.gov (United States)

    Procópio, Thamara Figueiredo; Fernandes, Kenner Morais; Pontual, Emmanuel Viana; Ximenes, Rafael Matos; de Oliveira, Aline Rafaella Cardoso; Souza, Carolina de Santana; Melo, Ana Maria Mendonça de Albuquerque; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes; Martins, Gustavo Ferreira; Napoleão, Thiago Henrique

    2015-01-01

    In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution

  13. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    Directory of Open Access Journals (Sweden)

    Thamara Figueiredo Procópio

    Full Text Available In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4, as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae and 1.03% (fed larvae. Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae, 61.7% of individuals emerged as adults. The extract (1.0% promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates

  14. Experiment prediction for Loft Nonnuclear Experiment L1-4

    International Nuclear Information System (INIS)

    White, J.R.; Berta, V.T.; Holmstrom, H.L.O.

    1977-04-01

    A computer analysis, using the WHAM and RELAP4 computer codes, was performed to predict the LOFT system thermal-hydraulic response for Experiment L1-4 of the nonnuclear (isothermal) test series. Experiment L1-4 will simulate a 200 percent double-ended offset shear in the cold leg of a four-loop large pressurized water reactor. A core simulator will be used to provide a reactor vessel pressure drop representative of the LOFT nuclear core. Experiment L1-4 will be initiated with a nominal isothermal primary coolant temperature of 282.2 0 C, a pressurizer pressure of 15.51 MPa, and a primary coolant flow of 270.9 kg/s. In general, the predictions of saturated blowdown for Experiment Ll-4 are consistent with the expected system behavior, and predicted trends agree with results from Semiscale Test S-01-4A, which simulated the Ll-4 experiment conditions

  15. The effects of waterborne uranium on the hatching success, development, and survival of early life stages of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Bourrachot, Stephanie; Simon, Olivier; Gilbin, Rodolphe

    2008-01-01

    In this study, we investigated the effects of the radioactive metal uranium (U) on the embryonic development, hatching success, growth rate, and survival of juvenile zebrafish (Danio rerio). We studied the effects of depleted uranium (20-500 μg L -1 of DU), inducing mainly chemical toxicity due to its low specific activity, and the combined effects of chemical and radiological toxicity by using a higher specific activity uranium isotope (20 and 100 μg L -1 of 233 U). Results showed that early life stages are significantly affected by uranium exposure through both chemical and combined (chemical and radiological) toxicity. Experiments showed significant effects of U on hatching success starting at the concentration of 250 μg L -1 of DU, causing a 42% delay in median hatching times relative to control. Furthermore, a reduction of growth (decrease in body length and weight) was observed followed by a high mortality of pro-larvae stage (up to 100% at DU concentrations of 250 μg L -1 upon a 15 day exposure). Bioaccumulation measurements highlighted that U was mainly localised in the chorion but penetrated in the embryo inside eggs at a higher concentration. The effects differed depending on the isotopic composition of the uranium: sublethal defects in the tail detachment process were more pronounced for 233 U than DU exposure, while the presence of 233 U specifically affected embryo development and led to higher mortality rates of the prolarvae. The results from this study showed that the early life stages of zebrafish seems to be more sensitive to uranium contamination than more mature stages, and underline the importance of including pro-larval stages into toxicity tests in order to improve the relevancy for environmental risk assessments

  16. Clinicopathologic implications of the miR-197/PD-L1 axis in oral squamous cell carcinoma.

    Science.gov (United States)

    Ahn, Hyein; Yang, Jeong Mi; Kim, Hyojin; Chung, Jin-Haeng; Ahn, Soon-Hyun; Jeong, Woo-Jin; Paik, Jin Ho

    2017-09-12

    Immune escape of a tumor from tumor-infiltrating lymphocytes (TILs) is induced by PD-L1, which is suppressed by miR-197. We investigated the clinicopathologic implications of the miR-197/PD-L1 axis and its effects on TILs and the clinicopathologic features of oral squamous cell carcinoma (OSCC). We used RT-PCR and immunohistochemistry in 68 OSCC patients to analyze the correlations between tumoral expression of miR-197 and PD-L1 and the degree of tumoral invasion by TILs (CD3+, CD4+, CD8+, PD-1+, FoxP3+, and CD20+ lymphocytes). PD-L1 levels correlated inversely with miR-197 but correlated positively with TILs. The aggressive features of OSCC, including high stage, angiolymphatic invasion, perineural invasion, and death, were associated with TIL depletion. High T stage (T4) tumors also had low PD-L1 but had high miR-197 expression. In a univariate survival analysis of the full cohort, high miR-197 was associated with poor overall survival, whereas high PD-L1 expression (2+) associated with good overall survival. In a multivariate analysis stratified based on miR-197 (median), high PD-L1 expression (2+) was an independent favorable prognostic factor for overall survival ( P = 0.040) in the miR-197 high subgroup but not the miR-197 low subgroup. These findings may have clinicopathologic implications for the miR-197/PD-L1 axis and TILs in OSCC.

  17. L1 Generalized Procrustes 2D Shape Alignment

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Eiriksson, Hrafnkell

    2002-01-01

    enabling the use of wellknown and thoroughly tested standard numerical software. This is achieved by using the city block distance between points in the plane. However, the city block distance is dependent on the orientation of the coordinate system. By simultaneously minimising the city block distances...... achieve deviations from Euclidean distances less than 2 \\$\\backslash\\$% over all directions. This new formulation allows for minimization in the \\$L\\_1\\$-norm using LP. We demonstrate that the use of the \\$L\\_1\\$-norm results in resistance towards object as well as landmark outliers. Examples...

  18. Density, Viability Conidia And Symptoms of Metarhizium anisopliae infection on Oryctes rhinoceros larvae

    Science.gov (United States)

    Indriyanti, D. R.; Putri, R. I. P.; Widiyaningrum, P.; Herlina, L.

    2017-04-01

    M. anisopliae is parasitic fungus on insect pests; it is used as a biocontrol agent. M. anisopliae can be propagated on maize or rice substrate. M. anisopliae is currently sold in the form of kaolin powder formulations. Before it is used to check the density, viability and pathogenicity of M. anisopliae. However the problem is the kaolin powder very soft, so it difficult to distinguish between kaolin and conidia. This article gives information on how to calculate conidia density, viability and symptoms of M. anisopliae infection on Oryctes rhinoceros larvae. The study was conducted in the laboratory to determine the density and viability. The pathogenicity testing was done using pots. The Pot is containing soil substrate mixed with M. Anispoliae and ten tails O. Rhinoceros larvae per pot. The results showed that the density of M. anisopliae conidia was 1.81 x 108 conidia mL-1 and the viability was 94% within 24 hours. The larval mortality began to emerge in the 1st week, and all larvae died at the sixth week. The symptom of M. anisopliae infection on Oryctes rhinoceros larvae, there was a black spot on the larval integument. The larvae movements become slow and poor appetite; it will die within 3-7 days. The larvae die hard, and the white hyphae grow on the body surface that turns green.

  19. Snail Larvae From Turbulent Inlets and the Wavy Continental Shelf Use Different Physical Behavioral Cues

    Science.gov (United States)

    Fuchs, H. L.; Gerbi, G. P.

    2016-02-01

    Dispersing larvae experience hydrodynamic signals from turbulence and waves; these signals vary geographically in their intensity and may cue behaviors enhancing transport to suitable habitats. Turbulence dominates the production of spatial velocity gradients (strain or vorticity), whereas waves often dominate the production of accelerations. Spatial patterns in these two signal types create a potential mechanism for larvae to distinguish or navigate among habitats. We quantified flow-induced behaviors in late-stage larvae of congeneric snails from turbulent coastal inlets (Ilyanassa obsoleta) and from the wavy continental shelf (Ilyanassa trivittata). Larvae were exposed to turbulence and to simpler flows dominated by strain, vorticity, or wave-generated acceleration. Fluid flow and individual larvae were observed simultaneously using infrared, particle-image velocimetry. In turbulence, larvae of both species sank or swam downward more frequently at higher dissipation rates, but the average vertical velocities of I. obsoleta became more negative (downward) than those of I. trivittata. In simpler flows, larvae of I. obsoleta reacted more strongly to vorticity-induced rotation relative to gravity, whereas only I. trivittata exhibited a strong reaction to wave-generated accelerations. Both species reacted to vorticity or acceleration in the absence of large strain rates, indicating that larvae likely sense flow using the statocysts. Although statocysts can sense two signal types, these closely related species responded differently to those signals, suggesting that behavior is attuned to the physical signals that dominate their respective adult habitats.

  20. Genes Expressed Differentially in Hessian Fly Larvae Feeding in Resistant and Susceptible Plants

    Directory of Open Access Journals (Sweden)

    Ming-Shun Chen

    2016-08-01

    Full Text Available The Hessian fly, Mayetiola destructor, is a destructive pest of wheat worldwide and mainly controlled by deploying resistant cultivars. In this study, we investigated the genes that were expressed differentially between larvae in resistant plants and those in susceptible plants through RNA sequencing on the Illumina platform. Informative genes were 11,832, 14,861, 15,708, and 15,071 for the comparisons between larvae in resistant versus susceptible plants for 0.5, 1, 3, and 5 days, respectively, after larvae had reached the feeding site. The transcript abundance corresponding to 5401, 6902, 8457, and 5202 of the informative genes exhibited significant differences (p ≤ 0.05 in the respective paired comparisons. Overall, genes involved in nutrient metabolism, RNA and protein synthesis exhibited lower transcript abundance in larvae from resistant plants, indicating that resistant plants inhibited nutrient metabolism and protein production in larvae. Interestingly, the numbers of cytochrome P450 genes with higher transcript abundance in larvae from resistant plants were comparable to, or higher than those with lower transcript abundance, indicating that toxic chemicals from resistant plants may have played important roles in Hessian fly larval death. Our study also identified several families of genes encoding secreted salivary gland proteins (SSGPs that were expressed at early stage of 1st instar larvae and with more genes with higher transcript abundance in larvae from resistant plants. Those SSGPs are candidate effectors with important roles in plant manipulation.

  1. Robotic Asteroid Prospector (RAP) Staged from L-1: Start of the Deep Space Economy

    Data.gov (United States)

    National Aeronautics and Space Administration — Robotic Asteroid Prospector (RAP) project will examine and evaluate the feasibility of asteroid mining in terms of means, methods, and systems.The objectives of the...

  2. on the eggs and L1 and L2 larval stages

    African Journals Online (AJOL)

    user2

    2012-10-16

    Oct 16, 2012 ... Comparisons of different mortality rates were made using the. Chi-square test and the results regarded as significant at P< 0.05. RESULTS. Egg hatch assay. The effects of CWE, HWE and EtE extracts on the fresh eggs of H. bakeri are given in Figure 1. The mean inhibition rates were 0% for both distilled ...

  3. A new mutant, White larva, of the mosquito Toxorhynchites splendens: genetics and cannibalism.

    Science.gov (United States)

    Horio, M; Tsukamoto, M; Miyagi, I

    1990-09-01

    A strain of a new body-color mutant, white larva (wl), was established from a field-collected wild-type strain of Toxorhynchites splendens. The mutant can be distinguished from the wild type in both the larval and pupal stages, but not in the adult. Crossing experiments confirmed its mode of inheritance to be a single recessive system. This is the first visible mutant found in Tx. splendens. Larvae of the wl phenotype seem to be recognized as prey by other individuals in mass larvae rearing.

  4. Egg Predation Risk Trigger Adult Hoverfly (Diptera: Syrphidae to Avoid Laying Eggs in Patches Attended by Ladybird Larvae (Coleoptera: Coccinellidae

    Directory of Open Access Journals (Sweden)

    Nugroho Susetya Putra

    2005-12-01

    Full Text Available Oviposition preference of a predatory hoverfly, Episyrphus balteatus on the presence of its potential predators, the ladybird larvae which are inflicted serious impacts on its eggs was examined in a non-choice test. Our results revealed that the biggest and the most aggressive species of ladybird, Harmonia axyridis caused the worst impact on hoverfly eggs by attacking and feeding on. The species and developmental stages of ladybird were attributed to the level of predation risk. We correlated the oviposition site selection by hoverfly females to the egg predation risk level inflicted by ladybird larvae. Hoverfly females laid the least number of eggs on the patches attended by the strongest competitor, the larva of H. axyridis, and tended to lay the highest number of eggs on colonies attended by the weakest competitor, the larva of Scymnus posticalis. In addition, the impact of the fourth instar larva of ladybirds was stronger than of the first instar larva.

  5. Conceptualising the Potential Role of L1 in CLIL

    Science.gov (United States)

    Lin, Angel M. Y.

    2015-01-01

    Content and language integrated learning (CLIL) is a rapidly growing area of both research and practice in all parts of the world, especially in Europe and Asia. As a young discipline, CLIL has a good potential of distinguishing itself from monolingual L2 immersion education models by becoming more flexible and balanced about the role of L1 in…

  6. PD-L1 blockade: rejuvenating T cells in CLL

    NARCIS (Netherlands)

    Kater, Arnon P.; van der Windt, Gerritje J. W.

    2015-01-01

    In this issue of Blood, there are 2 articles by McClanahan et al describing T-cell defects in murine chronic lymphocytic leukemia (CLL) in the context of aging which show that therapeutic targeting of programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) signaling prevents immune

  7. L1-convergence of complex double Fourier series

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    L1-convergence of complex double Fourier series. KULWINDER KAUR, S S BHATIA and BABU RAM. ∗. School of Mathematics and Computer Applications, Thapar Institute of Engineering and Technology, Post Box No. 32, Patiala 147 004, India. ∗. Department of Mathematics, Maharshi Dayanand University, Rohtak, India.

  8. A Characterization of Banach Spaces Containing l1

    Science.gov (United States)

    Rosenthal, Haskell P.

    1974-01-01

    It is proved that a Banach space contains a subspace isomorphic to l1 if (and only if) it has a bounded sequence with no weak-Cauchy subsequence. The proof yields that a sequence of subsets of a given set has a subsequence that is either convergent or Boolean independent. PMID:16592162

  9. Using L1 in Teaching English to Advanced Students

    Directory of Open Access Journals (Sweden)

    Khalid Al Hariri

    2015-11-01

    Full Text Available Using L1 in the English classroom has long been considered as an unforgivable wrongdoing. Many English teachers who use L1 in the classroom feel guilty about it and in many cases do not admit it. Recent researchers started to question the validity of this claim suggesting contexts and situations in which using L1 can be very helpful in ELT and refuting, on the other hand, the claims upon which the idea of using L2 solely were built.  My paper will examine the attitudes of advanced English language learners toward using L1 in the class of English where the students and the teacher speak the same first language and will also examine the attitudes of a group of EFL and ESL teachers toward the same practice. The same questionnaire given to the students will be redesigned and given to a number of teachers so that the study will look at the viewpoints from both perspectives.

  10. Raising Learners' Awareness through L1-L2 Teacher Collaboration

    Science.gov (United States)

    Gunning, Pamela; White, Joanna; Busque, Christine

    2016-01-01

    There is considerable interest in teacher collaboration across mother tongue and second language curricula. However, cross-curricular collaboration in reading strategy instruction has seldom been investigated. We report a two-year study involving collaboration between the French first language (L1) and English second language (L2) teachers in an…

  11. Effects of water-borne copper on the survival, antioxidant status, metallothionein-I mRNA expression and physiological responses of the Chinese mitten crab, Eriocheir sinensis (Decapoda: Brachyura larvae

    Directory of Open Access Journals (Sweden)

    Shengming Sun

    2014-03-01

    Full Text Available The lethal concentration of water-borne copper in Chinese mitten crab Eriocheir sinensis larvae was tested by exposing the animals to 0, 0.1, 0.2, 0.3, 0.5 and 0.8 mg Cu L-1 at 20°C for 96 h. The 96-h median lethal concentration (LC50 and its corresponding 95% confident interval was estimated on zoea 1 larvae and megalopa larvae, respectively. Acute dissolved copper toxicity was higher for zoea 1 larvae (0.16 mg L-1 than for megalopa larvae (0.21 mg L-1. The antioxidant status, metallothionein-I mRNA expression and physiological response of the crab to copper toxicity was further investigated by exposing the megalopa larvae to 0, 0.08 and 0.16 mg Cu L-1 for 96 h. The superoxide dismutase activity, catalase activity, glutathione S-transferase (GST activity and lipid peroxidation content of megalopa larvae increased concomitantly with the exposure time and copper concentration. MT-I mRNA expression levels were positively correlated with both the concentration and duration of copper exposure. The oxygen consumption and respiratory quotient of megalopa larvae in response to 0.16 mg L-1 copper were significantly higher than those in the control group after 96 h of exposure (P < 0.05. The results of this study highlight the potential effects of copper as a common stressor in E. sinensis larvae. MT-I and GST appear to be suitable biomarkers of environmental copper exposure stress in E. sinensis larvae

  12. Biodegradation of alkaline lignin by Bacillus ligniniphilus L1

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Daochen; Zhang, Peipei; Xie, Changxiao; Zhang, Weimin; Sun, Jianzhong; Qian, Wei-Jun; Yang, Bin

    2017-02-21

    Background: Lignin is the most abundant aromatic biopolymer in the biosphere and it comprises up to 30% of plant biomass. Although lignin is the most recalcitrant component of the plant cell wall, still there are microorganisms able to decompose it or degrade it. Fungi are recognized as the most widely used microbes for lignin degradation. However, bacteria have also been known to be able to utilize lignin as a carbon or energy source. Bacillus ligniniphilus L1 was selected in this study due to its capability to utilize alkaline lignin as a single carbon or energy source and its excellent ability to survive in extreme environments. Results: To investigate the aromatic metabolites of strain L1 decomposing alkaline lignin, GC-MS analyze was performed and fifteen single phenol ring aromatic compounds were identified. The dominant absorption peak included phenylacetic acid, 4-hydroxy-benzoicacid, and vanillic acid with the highest proportion of metabolites resulting in 42%. Comparison proteomic analysis were carried out for further study showed that approximately 1447 kinds of proteins were produced, 141 of which were at least 2-fold up-regulated with alkaline lignin as the single carbon source. The up-regulated proteins contents different categories in the biological functions of protein including lignin degradation, ABC transport system, environmental response factors, protein synthesis and assembly, etc. Conclusions: GC-MS analysis showed that alkaline lignin degradation of strain L1 produced 15 kinds of aromatic compounds. Comparison proteomic data and metabolic analysis showed that to ensure the degradation of lignin and growth of strain L1, multiple aspects of cells metabolism including transporter, environmental response factors, and protein synthesis were enhanced. Based on genome and proteomic analysis, at least four kinds of lignin degradation pathway might be present in strain L1, including a Gentisate pathway, the benzoic acid pathway and the

  13. Immune response of rainbow trout (Oncorhynchus mykiss) larvae to Yersinia ruckeri

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Kania, Per Walter; Raida, Martin Kristian

    Innate immune factors play a crucial role in survival of young fish especially during early stages of life where adaptive immunity is not fully developed. In the present study, we investigated the immune response of rainbow trout larvae (Onchorhynchus mykiss) at an early stage of development. We...

  14. Effect of gamma radiation on the Mediterranean flour moth, Ephestia Kuehniella, mature larvae and acceptability of irradiated larvae by Bracon hebetor female

    International Nuclear Information System (INIS)

    Mansour, M.

    2012-01-01

    Mediterranean flour moth, Ephestia kuehniella, mature 5 t h instar larvae were exposed to gamma radiation dosages ranging from 50-350 Gy at 50 Gy increment and the effects of gamma radiation on pupation, adult emergence and sex ratio were investigated. In addition, effects of irradiation on the rate of development to pupae and adults and the acceptance of irradiated larvae by B. hebetor females were examined. Results showed that the radio-sensitivity of E. kuehniella larvae increased with increasing dose. Pupation was significantly affected at 100 Gy dose, and completely prevented at 350 Gy dose. Adult emergence was only slightly different from pupation; emergence was significantly affected at 100 Gy dose and completely prevented at 300 Gy dose. Irradiation also negatively affected the rate of development of larvae to pupae and adults. While more than 98% of control larvae pupated within 10 days of treatment, this ratio decreased to about 79% in larvae exposed to 50 Gy and less than 4% in larvae exposed to 100 Gy dose. The rate of development to the adult stage was also similarly affected. While 97% of control insects emerged as adults in the 1st 20 days of treatment, this ratio decreased to about 53, 2 and zero percent in larvae exposed to 50, 100 and 150 Gy dose respectively. In addition, irradiation significantly affected male: female ratio; sex ratio was skewed in favor of males, and at 250 Gy dose all emerged moths were males. Furthermore, irradiation had no adverse effect on the degree of acceptance of mature larvae to parasitization; irradiated insects were as acceptable to B. hebetor females as unirradiated ones. (author)

  15. Isolamento de esporos de Paenibacillus larvae subsp. larvae no Brasil Detectionof Paenibacillus larvae subsp. larvae spores in Brazil

    Directory of Open Access Journals (Sweden)

    Dulce Maria Tocchetto Schuch

    2003-03-01

    Full Text Available Este trabalho objetivou detectar presença de esporos de Paenibacillus larvae subsp. larvae em produtos de um entreposto do interior do Estado do Rio Grande do Sul, a identificação de possíveis fontes de contaminação e a avaliação da possibilidade da transferência de esporos para colméias de apiários adjacentes a partir de produtos importados contaminados. Foram analisados mel e pólen importados disponíveis no entreposto, favo do ninho (crias, pólen e mel colhido de uma colméia sadia, mel estocado em um dos apiários e abelhas adultas. Os resultados foram positivosem relação ao mel e pólen importados, a três grupos de abelhas adultas e ao mel do favo.The objective of this work was to detect the presence of Paenibacillus larvae subsp. larvae spores in products from a warehouse located in Rio Grande do Sul State, Brazil, the identification of possible contamination sources, and the assessment of spores transference possibility from contaminated imported products from the warehouse to apiaries located in the surrounding area. Samples of imported pollen and bulk honey stocked in the warehouse, and honeycomb (brood, honey and pollen from a healthy hive, honey from one apiary and adult bees were analyzed. Imported honey and pollen, and three groups of adult bees and the honey collected from the honeycomb resulted positive.

  16. Temperature responses in larvae of Macoma balthica from a northerly and southerly population of the European distribution range

    NARCIS (Netherlands)

    Drent, J

    2002-01-01

    Planktonic marine invertebrate embryos and larvae experience high mortality rates. Processes during these early vulnerable stages of development are an important determinant of the dynamics of marine invertebrate populations. In order to evaluate possible specific local adaptations of the bivalve

  17. Delivery of marine larvae to shore requires multiple sequential transport mechanisms.

    Science.gov (United States)

    Pfaff, Maya C; Branch, George M; Fisher, Jennifer L; Hoffmann, Vera; Ellis, Allan G; Largier, John L

    2015-05-01

    Most sedentary marine animals disperse from their place of origin during their initial life stages as larvae. The delivery of planktonic larvae back to coastal adult habitats after weeks or months of offshore development is commonly thought to be stochastic, resulting in large recruitment fluctuations and making predictive understanding of population dynamics difficult. Time series of invertebrate settlement on intertidal shores have been used to infer how various oceanographic processes deliver planktonic larvae ashore. However, the possibility that successful settlement may involve a series of different transport mechanisms, which are sequentially utilized by late-stage larvae, has received little attention. To address this, we monitored both the delivery of mussel and barnacle larvae to inner-shelf moorings positioned 200-1400 m from the shore, and larval settlement in the intertidal adult habitat, at two contrasting sites: a headland forming an upwelling center and a downstream bay. Model selection was employed to determine the most likely scenario(s) of larval onshore transport from four a priori transport mechanisms individually and in combination: (1) upwelling or relaxation/downwelling, (2) tidal motions, (3) diurnal sea breezes, and (4) surface waves. Mussel larvae were delivered to the inner shelf during upwelling in the bay, but during downwelling at the headland, and were further transported to the shore by surface waves at both locales. In contrast, the delivery of barnacle larvae to the inner shelf occurred during relaxation/downwelling events at both sites, and intertidal settlement coincided with spring tides, suggesting a role for internal tides in their onshore transport. Thus, sequential mechanisms appear to be utilized by larvae to get to the shore, involving interactions of regional-scale upwelling/downwelling processes and local-scale tidal and surface-wave processes, which differ among taxa and among sites with different topography. A

  18. [Studies on susceptibility of Pomacea canaliculata of different developmental stages to infection with Angiostrongylus cantonensis].

    Science.gov (United States)

    Liu, He-xiang; Zhang, Yi; Zhou, Xiao-nong; Lv, Shan; Zhu, Dan; Lin, Jin-xiang; Li, Li-sha; Li, You-song; Yin, Wei-gang

    2005-10-30

    OBJECTIVE To study the susceptibility of Pomacea canaliculata of different developmental stages to Angiostrongylus cantonensis infection. P. canaliculata snails breeding at laboratory were divided into four rank (I-IV) according to the weight, and infected with the first stage larvae of A. cantonensis from Fujian Province. Their mortality, infection rate, worm burden, and the size, development and distribution of larvae in snails were examined. Snails at different developmental stages were readily infected with A. cantonensis. The infection rate was between 76% and 100%, with no significant difference among the groups (P>0.05). Snails at earlier developmental stage showed higher mortality. The heaviest worm burden and the largest number of snails harboring more than 100 larvae were found in snails of rank III. In general the larvae in snails showed a synchronous development in the groups. Sizes of the third stage larvae in snails of various ranks were homogeneous. The period before the third stage larva emergence and the time for a peak percentage of the larvae exhibited no significant difference among the four ranks. The larvae widely distributed in various parts of snails, with more in the lung and foot, and larvae from snails of different ranks could all infect rats successfully. P. canaliculata of the four ranks can all be infected by the first stage larvae of A. cantonensis. Rank III snails may be better for studying the relationship between P. canaliculata and A. cantonensis. The potential role of young snails in angiostrongyliasis transmission should be recognized.

  19. Cryopreservation of veliger larvae of trumpet shell, Charonia sauliae: an essential preparation to artificial propagation

    Science.gov (United States)

    Kang, Kyoung Ho; Zhang, Zhifeng; Bao, Zhenmin; Shao, Mingyu

    2009-09-01

    Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocol for the cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds of cryoprotectants (ethylene glycol, 1, 2-propanediol, dimethyl sulfoxide and glycerol) were employed at three concentrations (1.0, 1.5 and 2.0 molL-1) respectively and survival rates of larvae were determined after a storage of 1h. The larvae frozen with these four cryoprotectants after 1 h storage were cultured, and then survival rates were determined at 24, 72 and 120 h after thawing. Dimethyl sulfoxide at a concentration of 1.5 molL-1 showed the best protective effect in all experiments ( p0.05).

  20. L1 Transfer in Post-Verbal Preposition: An Inter-level Comparison

    Directory of Open Access Journals (Sweden)

    Samira Mollaei

    2013-10-01

    Full Text Available The study intended to investigate the well-known issue of L1 transfer in L2acquisition. The primary aim of this research was to compare the extent to which L1 transfer may take place in different developmental stages in L2 learning procedure. Persian learners of English have been observed to misuse a number of the prepositions with some of the verbs. Having scrutinized more than a hundred pieces of students’ writing assignments, the authors came up with a pattern of errors in this area. It was observed that the majority of these errors could be attributed to Persian: the learners’ choice of preposition mirror the corresponding case in their L1, Persian. Moreover, the pattern of mistakes was put to test to check whether these mistakes increase or decrease according to the level of proficiency of the learners. To this end, two groups of students, one in elementary and the other in intermediate level, were tested on their use of proper prepositions with different verbs and the results of these tests were compared to see whether any significant difference exists between the two groups of students. The results showed no significant difference between the students of the two proficiency levels.

  1. LOFT advanced densitometer L1-4 test

    International Nuclear Information System (INIS)

    Wood, D.B.

    1978-01-01

    The report covers the PC-2, C-beam chordal average density measurement made on the loss-of-fluid test (LOFT) primary coolant system hot leg during the L1-4 nonnuclear loss-of-coolant accident (LOCA) test conducted May 3, 1977. The P-2, C-beam, or LOFT advanced densitometer, used was of the pulse height analysis/energy discrimination, or nuclear hardened type to be used for LOFT nuclear tests. The L1-4 test verified the applicability of pulse height analysis/energy discrimination techniques of the nuclear hardened gamma densitometer. Test results show that the reactor coolant fluid chordal average density can be calculated from gamma radiation source signal measured count rate data

  2. Radiosensitivity of spores of Paenibacillus larvae ssp. larvae in honey

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Wanderley Mendes de [Ministerio da Agricultura, Pecuaria e Abastecimento, Rio de Janeiro, RJ (Brazil). Servico de Inspecao de Produtos de Origem Animal]. E-mail: sipa-rj@agricultura.gov.br; Vital, Helio de Carvalho [Centro Tecnologico do Exercito CTEx, Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear]. E-mail: vital@ctex.eb.br; Schuch, Dulce Maria Tocchetto [Ministerio da Agricultura, Pecuaria e Abastecimento, Porto Alegre, RS (Brazil)]. E-mail: micro-lara-rs@agricultura.gov.br

    2007-07-01

    Irradiation, usually used in combination with other conventional methods of conservation, has been proven to be an efficient tool to ensure the safety of many types of foods by destroying pathogenic microorganisms and extending their shelf-lives. This work has investigated the efficacy of gamma irradiation to inactivate spores of the bacterium Paenibacillus larvae that causes the 'American foulbrood', a highly contagious disease still exotic in Brazil that kills bees and contaminates honey, preventing its commercialization and causing great economical losses. In this study, 60 g samples of two types of honey inoculated with 3.5x10{sup 3} spores/mL of that bacterium were irradiated with doses of 0, 5, 7.5, 10, 12.5 and 15 kGy and counted. The analyses indicated a mean reduction of 97.5{+-}0.7% in the number of viable spores exposed to 5 kGy. The application of doses of 7.5 kGy or higher yielded no viable spores above the detection threshold (10/mL). In addition the value of D{sub 10} (3.1{+-}0.3 kGy) was estimated and the logarithm of the population of viable spores of Paenibacillus larvae subsp. larvae was determined as linear and quadratic polynomial functions of the radiation dose. The results indicated that the dose of 10 kGy could be insufficient to assure complete sterilization of honey in some cases while suggesting that 25 kGy would perform such task adequately. (author)

  3. Induced metamorphosis in crustacean y-larvae: towards a solution to a 100-year-old riddle

    DEFF Research Database (Denmark)

    Glenner, Henrik; Høeg, Jens T; Grygier, Mark J

    2008-01-01

    BACKGROUND: The y-larva, a crustacean larval type first identified more than 100 years ago, has been found in marine plankton samples collected in the arctic, temperate and tropical regions of all oceans. The great species diversity found among y-larvae (we have identified more than 40 species......-larvae into a novel, highly reduced juvenile stage by applying the crustacean molting hormone 20-HE. The new stage is slug-like, unsegmented and lacks both limbs and almost all other traits normally characterizing arthropods, but it is capable of vigorous peristaltic motions. CONCLUSION: From our observations on live...

  4. Feeding behavior and capture success of turbot Psetta maxima larvae during the transition from upright to tilted swimming position

    DEFF Research Database (Denmark)

    Bruno, Eleonora; Mahjoub, Mohamed Sofiane; Hansen, Benni Winding

    2017-01-01

    larvae. In order to ascertain changes in feeding during metamorphosis of flatfish, we here compared feeding behavior when larvae of turbot Psetta maxima were either swimming upright or tilted. Using video recordings, we compared the attack rate and prey capture success between flexion (12-13 days-post-hatch......, stage 4b-4c) swimming predominantly in upright position and post-flexion (16-17 days-post-hatch, stage 5a-5b) larvae in tilted swimming mode. Both larval groups were fed on copepod nauplii and copepodites. Our results showed a capture success of

  5. Conditions for l =1 Pomeranchuk instability in a Fermi liquid

    Science.gov (United States)

    Wu, Yi-Ming; Klein, Avraham; Chubukov, Andrey V.

    2018-04-01

    We perform a microscopic analysis of how the constraints imposed by conservation laws affect q =0 Pomeranchuk instabilities in a Fermi liquid. The conventional view is that these instabilities are determined by the static interaction between low-energy quasiparticles near the Fermi surface, in the limit of vanishing momentum transfer q . The condition for a Pomeranchuk instability is set by Flc (s )=-1 , where Flc (s ) (a Landau parameter) is a properly normalized partial component of the antisymmetrized static interaction F (k ,k +q ;p ,p -q ) in a charge (c) or spin (s) subchannel with angular momentum l . However, it is known that conservation laws for total spin and charge prevent Pomeranchuk instabilities for l =1 spin- and charge-current order parameters. Our study aims to understand whether this holds only for these special forms of l =1 order parameters or is a more generic result. To this end we perform a diagrammatic analysis of spin and charge susceptibilities for charge and spin density order parameters, as well as perturbative calculations to second order in the Hubbard U . We argue that for l =1 spin-current and charge-current order parameters, certain vertex functions, which are determined by high-energy fermions, vanish at Fl=1 c (s )=-1 , preventing a Pomeranchuk instability from taking place. For an order parameter with a generic l =1 form factor, the vertex function is not expressed in terms of Fl=1 c (s ), and a Pomeranchuk instability may occur when F1c (s )=-1 . We argue that for other values of l , a Pomeranchuk instability may occur at Flc (s )=-1 for an order parameter with any form factor.

  6. Trophic ecology of Atlantic bluefin tuna Thunnus thynnus larvae.

    Science.gov (United States)

    Catalán, I A; Tejedor, A; Alemany, F; Reglero, P

    2011-05-01

    Feeding intensity, diet composition, selectivity, energy ingestion and dietary niche breadth of larval Atlantic bluefin tuna Thunnus thynnus were studied on the eastern (Mediterranean) spawning grounds of the species. Larval T. thynnus were collected in the Balearic Archipelago (north-west Mediterranean Sea) during 2004 and 2005 using surveys specific for larval scombrids. Larvae between 2·6 and 8·7 mm standard length (L(S) ) are diurnal feeders, and 94% of the guts collected during daylight hours were full. The mean ±s.d. number of prey per gut was 7·1 ± 5·7, with mean ±s.d. ranging from 3·0 ± 1·6 in the smallest T. thynnus larvae to 11·1 ± 5·8 in 5·0-6·0 mm L(S) larvae. Up to 21 prey were found in a single larval gut (5·0-6·0 mm L(S) ) at the end of the day. Larvae progressively selected larger prey and exhibited increased carbon content concurrent with preflexion development of feeding and locomotory structures. Larvae of 5·0-6·0 mm L(S) exhibited positive selection of cladocerans over other prey (Chesson's index), whereas copepod nauplii dominated the diets of earlier stages. The dietary niche breadth measured increased initially but decreased at c. 5·5 mm L(S) . Appendicularians were found in the diet of larger larval sizes, but no piscivory was observed. Results are discussed in light of the sparse existing data for larval T. thynnus and other larval tuna species. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles. No claim to original US government works.

  7. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Science.gov (United States)

    Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

    2015-01-01

    Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by

  8. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Directory of Open Access Journals (Sweden)

    George G Waldbusser

    Full Text Available Ocean acidification (OA is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4 with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material

  9. Feeding ω-3 PUFA enriched rotifers to Galaxias maculatus (Jenyns, 1842 larvae reared at different salinity conditions: effects on growth parameters, survival and fatty acids profile

    Directory of Open Access Journals (Sweden)

    Patricio Dantagnan

    2013-07-01

    Full Text Available Despite the well known importance of ω-3 polyunsaturated fatty acids (PUFA in marine and freshwater fish larvae, there are few studies on how essential fatty acid requirements and composition on whole body can be altered by changes in water salinity. The present study aimed to determine the effect of salinity on ω-3 PUFA requirements, larval growth survival and fatty acid composition of Galaxias maculatus larvae cultured at two different salinities (0 and 15 g L-1 for 20 days while fed rotifers containing two different levels of ω-3 PUFA (1.87 and 3.16%. The results denoted a marked difference in ω-3 PUFA requirements and in the pattern of fatty acid deposition in the whole body of larvae reared at different salinities, depending of ω-3 PUFA in diets. Thus, to improve growth and survival larvae of G. maculatus reared at 0 g L-1 require higher levels of ω-3 PUFA, principally 18:3 ω-3. Larvae reared at salinities of 15 g L-1 require low levels of ω-3 PUFA for optimal survival, especially 18:3 ω-3. Eicosapentaenoic acid and docosahexaenoic acid content in the whole body of larvae was also affected by water salinity.

  10. Citrus Seed Oils Efficacy against Larvae of Aedes aegypti.

    Science.gov (United States)

    Bilal, Hazrat; Akram, Waseem; Hassan, Soaib Ali; Din, Sadrud

    2017-09-01

    Dengue fever is a serious public health issue in Pakistan for many years. Globally plants have been reported to contain compounds with insecticidal properties. These properties have been demonstrated more recently on the larval stages of mosquitoes. Therefore, Citrus cultivar seeds were evaluated for larvicidal potential against the primary dengue vector Aedes aegypti . Extraction of oil was done by a steam distillation method and oils were evaluated according to WHO guidelines for larvicides 2005 for evaluation of insecticidal properties of citrus seed extracts against mosquito larvae. Among the Citrus cultivar seed oil, rough lemon ( Citrus jambhiri ) had the lowest LC 50 value (200.79ppm), while musambi ( C. sinensis var musambi ) had the highest LC 50 value (457.30ppm) after 24 h of exposure. Citrus cultivars have some larvicidal potential but C. jambhiri had the greatest potential against A. aegypti larvae. Further small-scale field trials using the extracts of C. jambhiri will be conducted to determine operational feasibility.

  11. Extreme morphologies of mantis shrimp larvae

    DEFF Research Database (Denmark)

    Haug, Carolin; Ahyong, Shane T.; Wiethase, Joris H.

    2016-01-01

    diversity of stomatopod larvae, which is largely unstudied. We describe here four previously unknown larval types with extreme morphologies. All specimens were found in the collections of the Zoological Museum, University of Copenhagen and were collected during the Danish Dana Expedition round the world...... was possible. Further investigations of these larvae are crucial to understand their life habits and ecological impact, especially as stomatopod and other crustacean larvae might have a much more important position in the marine ecosystems than their corresponding adults....

  12. Brief Exposure to Turbulence Permanently Alters Development of Sand Dollar Larvae

    Science.gov (United States)

    Ferner, M. C.; Hodin, J.; Ng, G.; Lowe, C. J.; Gaylord, B.

    2016-02-01

    Fluid motion underlies interactions between animals and their environment through effects on locomotion, food capture, respiration, information transfer, and other processes. Recent studies of marine invertebrates indicate that metamorphosis and settlement can be altered when swimming larvae experience a change in turbulence intensity, possibly increasing the likelihood that larvae will settle in appropriate habitat. For example, brief exposure to levels of turbulence characteristic of wave-swept coasts causes echinoderm larvae to quickly transition from a non-responsive "pre-competent" stage into a "competent" stage, thereby allowing the larvae to respond to local cues and settle. However, responding to one's entry into the nearshore environment isn't enough, as many such species live as adults in a narrower range of highly specific benthic habitat that is even more rarely encountered. Here we provide an account for this apparent mismatch between larval responses to broadly distributed cues and their need for more specialized settlement locations: turbulence exposure seems to cause larval sand dollars (Dendraster excentricus) to permanently shift from pre-competence to competence. This observation suggests a scenario where turbulence can activate a temporally extensive search image in larvae over a broad habitat range, a seemingly adaptive feature for larvae entering dynamic coastal environments.

  13. PREFERENSI PENEMPELAN, PERTUMBUHAN, DAN SINTASAN LARVA TERIPANG PASIR, Holothuria scabra PADA SUBSTRAT LAMUN YANG BERBEDA

    Directory of Open Access Journals (Sweden)

    Lisa Fajar Indriana

    2017-01-01

    Sandfish Holothuria scabra is marine commodities with a high economic value. Overfishing of natural stocks has compelled an interest to begin aquaculture practice. Settlement is a critical phase for the planktonic larvae as they will transform to benthic form in the presence of substrate. This study aims to evaluate the settlement preferences, growth, and survival rate of H. scabra larvae settled on different seagrass leaves. The research was conducted using the Completely randomized design with four different species of seagrass leaves and five replications. The treatments consist of Enhalus acoroides (L-1, Syringodium isoetifolium (L-2, Cymodocea serrulata (L-3, and Cymodocea rotundata (L-4. Initial number of larvae was 1,000 individuals and the substrate was set with same widthof 12 cm x 17 cm for each unit. Results of the experiment indicated that settlement preference and survival rate of H. scabra larvae was significantly affected by seagrass used as substrate while no significantly differences was observed for growth of larvae. E. acoroides showed the best result with 0.26 ind. cm-2 settelement preference and 10.66% survival rate, so that suitable to be used as settlement substrate in H. scabra hatchery.

  14. Development and functional morphology of the mouthparts and foregut in larvae and post-larvae of Macrobrachium jelskii (Decapoda: Palaemonidae).

    Science.gov (United States)

    Rocha, Cristina Pantoja; Souza, Adelson Silva de; Maciel, Murilo; Maciel, Cristiana R; Abrunhosa, Fernando Araújo

    2016-05-01

    The morphology of the mouthparts and foregut of the larvae and post-larvae of Macrobrachium jelskii was investigated to determine their functional roles in feeding, in order to understand the larval feeding behaviour and the changes that occur during its development. The mouthparts and foregut of the zoea I and II are morphologically similar, rudimentary and non-functional in feeding. Only in the final larval stage, zoea III, do the external mouthparts and foregut become structurally more complex and thus likely to play a potential role in feeding. Two behavioral trials (point of no return, point of reserve saturation) evaluated the resistance to starvation in zoea I, II, and III. The results indicate that they have sufficient nutritional reserves to permit them to complete metamorphosis without feeding. Overall, our results suggest that the zoea I and II of Macrobrachium jelskii engage in obligate lecithotrophy and zoea III in facultative lecithotrophy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Topiramate effects lipolysis in 3T3-L1 adipocytes.

    Science.gov (United States)

    Martins, Gabriela Poltronieri Campagnaro; Souza, Camila Oliveira; Marques, Scherolin; Luciano, Thais Fernandes; DA Silva Pieri, Bruno Luiz; Rosa, José César; DA Silva, Adelino Sanchez Ramos; Pauli, José Rodrigo; Cintra, Dennys Esper; Ropelle, Eduardo Rochete; Rodrigues, Bruno; DE Lira, Fabio Santos; DE Souza, Claudio Teodoro

    2015-11-01

    Studies have shown that topiramate (TPM)-induced weight loss can be dependent on the central nervous system (CNS). However, the direct action of TPM on adipose tissue has not been tested previously. Thus, the present study aimed to examine whether TPM modulates lipolysis in 3T3-L1. The 3T3-L1 cells were incubated in 50 µM TPM for 30 min. The β-adrenergic stimulator, isoproterenol, was used as a positive control. The release of lactate dehydrogenase, non-esterified fatty acid, glycerol and incorporation of 14 C-palmitate to lipid were analyzed. The phosphorylation of protein kinase A (PKA), hormone-sensitive lipase (HSL), adipocyte triglyceride lipase (ATGL) and perilipin A, as well as the protein levels of comparative genetic identification 58 (CGI-58) were assessed. The levels of glycerol and non-esterified fatty acid increased markedly when the cells were treated with TPM. The TPM effects were similar to the isoproterenol positive control. Additionally, TPM reduced lipogenesis. These results were observed without any change in cell viability. Finally, the phosphorylation of PKA, HSL, ATGL and perilipin A, as well as the protein levels of CGI-58 were increased compared to the control cells. These results were similar to those observed in the cells treated with isoproterenol. The present results show that TPM increased the phosphorylation of pivotal lipolytic enzymes, which induced lipolysis in 3T3-L1 adipocytes, suggesting that this drug may act directly in the adipose tissue independent from its effect on the CNS.

  16. Ecotoxicity of Lake Druksiai waters assessed by biotesting with rainbow trout spawn and larvae

    International Nuclear Information System (INIS)

    Kazlauskiene, N.; Cepuliene, Z.

    1998-01-01

    The toxicity of Lake Druksiai was assessed by testing with spawn and larvae of rainbow trout (Oncorhynchus mykiss). We sampled Ignalina NPP waste waters of various biotopes of the lake. Larvae of trout were found to be more sensitive to wastewaters than spawn. The hatching stage was one of the most sensitive stages in ontogenesis. Our data showed that the wastewater of Ignalina NPP was the most toxic, however waters of some biotopes of the lake were also toxic. That suggested that toxicants discharged into cooling reservoirs with NPP wastewater might affect test-organisms, disturbing their development and growth. The observed effects were irreversible and caused death. (author)

  17. Effects of the probiotic, Bacillus subtilis E20, on the survival, development, stress tolerance, and immune status of white shrimp, Litopenaeus vannamei larvae.

    Science.gov (United States)

    Liu, Kuan-Fu; Chiu, Chiu-Hsia; Shiu, Ya-Li; Cheng, Winton; Liu, Chun-Hung

    2010-01-01

    In this study, the probiotic, Bacillus subtilis E20, isolated from the human health food, natto, was used for white shrimp, Litopenaeus vannamei, larvae breeding to improve the larval survival rate and development by adding probiotic to the rearing water at (control), 10(8), and 10(9) cfu L(-1) salt water once every 3 days during the 14 days of breeding experiment. Thereafter, stress tolerance and immune status of postlarvae were evaluated. Shrimp larval development was significantly accelerated after adding the probiotic to the larval rearing water at a level of 10(9) cfu L(-1). The survival rate of larvae was significantly higher in the treatment with 10(9) cfu L(-1) compared to the control and the treatment with 10(8) cfu L(-1) after all larvae had metamorphosed to postlarvae. Adding the probiotic to the shrimp larvae rearing water produced a weak inhibition of bacterial growth by an analysis of the total bacterial count and presumptive Vibrio count. For stress tests, no postlarvae died when they were reared in water in which the temperature was decreased from 30 to 2 degrees C at a rate of 0.1 degrees C min(-1). Postlarvae had significantly lower cumulate mortality in the treatments with 10(8) and 10(9) cfu L(-1) compared to the control when they were suddenly exposed to fresh water and 60 per thousand salt water. A significant decrease in the cumulative mortality of postlarvae treated with the probiotic at a level of 10(9) cfu L(-1) was recorded after the sudden transfer to 300 mg L(-1) nitrite-N compared to the control and treatment with 10(8) cfu L(-1). The analysis of immune-related gene expressions showed that the gene expression of prophenoloxidase I, prophenoloxidase II, and lysozyme of larvae were significantly increased after being reared in probiotic-containing water at the levels of 10(8) and 10(9) cfu L(-1). However, no significant difference in serine proteinase or glutathione peroxidase gene expressions was recorded in this study. It is therefore

  18. L1 track finding for a time multiplexed trigger

    Energy Technology Data Exchange (ETDEWEB)

    Cieri, D., E-mail: davide.cieri@bristol.ac.uk [University of Bristol, Bristol (United Kingdom); Rutherford Appleton Laboratory, Didcot (United Kingdom); Brooke, J.; Grimes, M. [University of Bristol, Bristol (United Kingdom); Newbold, D. [University of Bristol, Bristol (United Kingdom); Rutherford Appleton Laboratory, Didcot (United Kingdom); Harder, K.; Shepherd-Themistocleous, C.; Tomalin, I. [Rutherford Appleton Laboratory, Didcot (United Kingdom); Vichoudis, P. [CERN, Geneva (Switzerland); Reid, I. [Brunel University, London (United Kingdom); Iles, G.; Hall, G.; James, T.; Pesaresi, M.; Rose, A.; Tapper, A.; Uchida, K. [Imperial College, London (United Kingdom)

    2016-07-11

    At the HL-LHC, proton bunches will cross each other every 25 ns, producing an average of 140 pp-collisions per bunch crossing. To operate in such an environment, the CMS experiment will need a L1 hardware trigger able to identify interesting events within a latency of 12.5 μs. The future L1 trigger will make use also of data coming from the silicon tracker to control the trigger rate. The architecture that will be used in future to process tracker data is still under discussion. One interesting proposal makes use of the Time Multiplexed Trigger concept, already implemented in the CMS calorimeter trigger for the Phase I trigger upgrade. The proposed track finding algorithm is based on the Hough Transform method. The algorithm has been tested using simulated pp-collision data. Results show a very good tracking efficiency. The algorithm will be demonstrated in hardware in the coming months using the MP7, which is a μTCA board with a powerful FPGA capable of handling data rates approaching 1 Tb/s.

  19. Cannabidiol promotes browning in 3T3-L1 adipocytes.

    Science.gov (United States)

    Parray, Hilal Ahmad; Yun, Jong Won

    2016-05-01

    Recruitment of the brown-like phenotype in white adipocytes (browning) and activation of existing brown adipocytes are currently being investigated as a means to combat obesity. Thus, a wide variety of dietary agents that contribute to browning of white adipocytes have been identified. The present study was designed to investigate the effects of cannabidiol (CBD), a major nonpsychotropic phytocannabinoid of Cannabis sativa, on induction of browning in 3T3-L1 adipocytes. CBD enhanced expression of a core set of brown fat-specific marker genes (Ucp1, Cited1, Tmem26, Prdm16, Cidea, Tbx1, Fgf21, and Pgc-1α) and proteins (UCP1, PRDM16, and PGC-1α). Increased expression of UCP1 and other brown fat-specific markers contributed to the browning of 3T3-L1 adipocytes possibly via activation of PPARγ and PI3K. In addition, CBD increased protein expression levels of CPT1, ACSL, SIRT1, and PLIN while down-regulating JNK2, SREBP1, and LPL. These data suggest possible roles for CBD in browning of white adipocytes, augmentation of lipolysis, thermogenesis, and reduction of lipogenesis. In conclusion, the current data suggest that CBD plays dual modulatory roles in the form of inducing the brown-like phenotype as well as promoting lipid metabolism. Thus, CBD may be explored as a potentially promising therapeutic agent for the prevention of obesity.

  20. L1 Adaptive Control for a Vertical Rotor Orientation System

    Directory of Open Access Journals (Sweden)

    Sijia Liu

    2016-08-01

    Full Text Available Bottom-fixed vertical rotating devices are widely used in industrial and civilian fields. The free upside of the rotor will cause vibration and lead to noise and damage during operation. Meanwhile, parameter uncertainties, nonlinearities and external disturbances will further deteriorate the performance of the rotor. Therefore, in this paper, we present a rotor orientation control system based on an active magnetic bearing with L 1 adaptive control to restrain the influence of the nonlinearity and uncertainty and reduce the vibration amplitude of the vertical rotor. The boundedness and stability of the adaptive system are analyzed via a theoretical derivation. The impact of the adaptive gain is discussed through simulation. An experimental rig based on dSPACE is designed to test the validity of the rotor orientation system. The experimental results show that the relative vibration amplitude of the rotor using the L 1 adaptive controller will be reduced to ∼50% of that in the initial state, which is a 10% greater reduction than can be achieved with the nonadaptive controller. The control approach in this paper is of some significance to solve the orientation control problem in a low-speed vertical rotor with uncertainties and nonlinearities.

  1. Acquisition of Japanese contracted sounds in L1 phonology

    Science.gov (United States)

    Tsurutani, Chiharu

    2002-05-01

    Japanese possesses a group of palatalized consonants, known to Japanese scholars as the contracted sounds, [CjV]. English learners of Japanese appear to treat them initially as consonant + glide clusters, where there is an equivalent [Cj] cluster in English, or otherwise tend to insert an epenthetic vowel [CVjV]. The acquisition of the Japanese contracted sounds by first language (L1) learners has not been widely studied compared with the consonant clusters in English with which they bear a close phonetic resemblance but have quite a different phonological status. This is a study to investigate the L1 acquisition process of the Japanese contracted sounds (a) in order to observe how the palatalization gesture is acquired in Japanese and (b) to investigate differences in the sound acquisition processes of first and second language (L2) learners: Japanese children compared with English learners. To do this, the productions of Japanese children ranging in age from 2.5 to 3.5 years were transcribed and the pattern of misproduction was observed.

  2. L1 Track Finding for a Time Multiplexed Trigger

    CERN Document Server

    AUTHOR|(CDS)2090481; Grimes, M.; Newbold, D.; Harder, K.; Shepherd-Themistocleous, C.; Tomalin, I.; Vichoudis, P.; Reid, I.; Iles, G.; Hall, G.; James, T.; Pesaresi, M.; Rose, A.; Tapper, A.; Uchida, K.

    2016-01-01

    At the HL-LHC, proton bunches will cross each other every 25 ns, producing an average of 140 p p-collisions per bunch crossing. To operate in such an environment, the CMS experiment will need a L1 hardware trigger able to identify interesting events within a latency of 12.5 us. The future L1 trigger will make use also of data coming from the silicon tracker to control the trigger rate. The architecture that will be used in future to process tracker data is still under discussion. One interesting proposal makes use of the Time Multiplexed Trigger concept, already implemented in the CMS calorimeter trigger for the Phase I trigger upgrade. The proposed track finding algorithm is based on the Hough Transform method. The algorithm has been tested using simulated pp-collision data. Results show a very good tracking efficiency. The algorithm will be demonstrated in hardware in the coming months using the MP7, which is a uTCA board with a powerful FPGA capable of handling data rates approaching 1 Tb/s.

  3. Bayesian model of categorical effects in L1 and L2 speech perception

    Science.gov (United States)

    Kronrod, Yakov

    In this dissertation I present a model that captures categorical effects in both first language (L1) and second language (L2) speech perception. In L1 perception, categorical effects range between extremely strong for consonants to nearly continuous perception of vowels. I treat the problem of speech perception as a statistical inference problem and by quantifying categoricity I obtain a unified model of both strong and weak categorical effects. In this optimal inference mechanism, the listener uses their knowledge of categories and the acoustics of the signal to infer the intended productions of the speaker. The model splits up speech variability into meaningful category variance and perceptual noise variance. The ratio of these two variances, which I call Tau, directly correlates with the degree of categorical effects for a given phoneme or continuum. By fitting the model to behavioral data from different phonemes, I show how a single parametric quantitative variation can lead to the different degrees of categorical effects seen in perception experiments with different phonemes. In L2 perception, L1 categories have been shown to exert an effect on how L2 sounds are identified and how well the listener is able to discriminate them. Various models have been developed to relate the state of L1 categories with both the initial and eventual ability to process the L2. These models largely lacked a formalized metric to measure perceptual distance, a means of making a-priori predictions of behavior for a new contrast, and a way of describing non-discrete gradient effects. In the second part of my dissertation, I apply the same computational model that I used to unify L1 categorical effects to examining L2 perception. I show that we can use the model to make the same type of predictions as other SLA models, but also provide a quantitative framework while formalizing all measures of similarity and bias. Further, I show how using this model to consider L2 learners at

  4. Aquatic respiration as a potential survival mechanism of Brephidium pseudofea (Lepidoptera: Lycaenidae) larvae to intertidal environments.

    Science.gov (United States)

    Warren, V; Daniels, J C; Hahn, D A

    2011-10-01

    The eastern pygmy blue, Brephidium pseudofea (Morrison) (Lepidoptera: Lycaenidae: Polyommatinae), inhabits intertidal environments that are periodically flooded. The immature stages are subject to salt or brackish water inundation during this time and therefore must endure many stressors, including respiratory limitation and salt exposure. Our goal was to investigate possible mechanisms used by the larval stages of B. pseudofea to endure periodic tidal inundation by using physiological and morphological analyses in comparison with several species of terrestrial lepidopteran larvae. A review of tidal charts showed that the immature stages of B. pseudofea would be prone to complete inundation two to five times per month during the summer months (May to August) and partial submersion for up to 20 d per month during the rest of the year. Larvae of several terrestrial lepidopteran species studied consumed oxygen under water for a limited period, but B. pseudofea demonstrated substantially higher oxygen consumption. Light microscopy of B. pseudofea larvae revealed small air pockets in and around the spiracles when submerged in tap water; these air pockets disappeared when exposed to detergent solution. The resulting air pockets may function as a diffusion layer for oxygen to be absorbed from the surrounding water or may act in conjunction with trans-cuticular gas exchange to meet the larva's respiratory needs. Morphological examination by scanning electron microscopy showed that B. psudofea larvae have distinctively small, clavate setae that appear insufficient to effectively support a functional plastron.

  5. Oxidative Stress and Digestive Enzyme Activity of Flatfish Larvae in a Changing Ocean

    Science.gov (United States)

    Pimentel, Marta S.; Faleiro, Filipa; Diniz, Mário; Machado, Jorge; Pousão-Ferreira, Pedro; Peck, Myron A.; Pörtner, Hans O.; Rosa, Rui

    2015-01-01

    Until now, it is not known how the antioxidant and digestive enzymatic machinery of fish early life stages will change with the combined effects of future ocean acidification and warming. Here we show that high pCO2 (~1600 μatm) significantly decreased metabolic rates (up to 27.4 %) of flatfish larvae, Solea senegalensis, at both present (18 °C) and warmer temperatures (+4 °C). Moreover, both warming and hypercapnia increased the heat shock response and the activity of antioxidant enzymes, namely catalase (CAT) and glutathione S-transferase (GST), mainly in post-metamorphic larvae (30 dph). The lack of changes in the activity of CAT and GST of pre-metamorphic larvae (10 dph) seems to indicate that earlier stages lack a fully-developed antioxidant defense system. Nevertheless, the heat shock and antioxidant responses of post-metamorphic larvae were not enough to avoid the peroxidative damage, which was greatly increased under future environmental conditions. Digestive enzymatic activity of S. senegalensis larvae was also affected by future predictions. Hypercapnic conditions led to a decrease in the activity of digestive enzymes, both pancreatic (up to 26.1 % for trypsin and 74.5 % for amylase) and intestinal enzymes (up to 36.1 % for alkaline phosphatase) in post-metamorphic larvae. Moreover, the impact of ocean acidification and warming on some of these physiological and biochemical variables (namely, lower OCR and higher HSP and MDA levels) were translated into larvae performance, being significantly correlated with decreased larval growth and survival or increased incidence of skeletal deformities. The increased vulnerability of flatfish early life stages under future ocean conditions is expected to potentially determine recruitment and population dynamics in marine ecosystems. PMID:26221723

  6. Oxidative Stress and Digestive Enzyme Activity of Flatfish Larvae in a Changing Ocean.

    Directory of Open Access Journals (Sweden)

    Marta S Pimentel

    Full Text Available Until now, it is not known how the antioxidant and digestive enzymatic machinery of fish early life stages will change with the combined effects of future ocean acidification and warming. Here we show that high pCO2 (~1600 μatm significantly decreased metabolic rates (up to 27.4 % of flatfish larvae, Solea senegalensis, at both present (18 °C and warmer temperatures (+4 °C. Moreover, both warming and hypercapnia increased the heat shock response and the activity of antioxidant enzymes, namely catalase (CAT and glutathione S-transferase (GST, mainly in post-metamorphic larvae (30 dph. The lack of changes in the activity of CAT and GST of pre-metamorphic larvae (10 dph seems to indicate that earlier stages lack a fully-developed antioxidant defense system. Nevertheless, the heat shock and antioxidant responses of post-metamorphic larvae were not enough to avoid the peroxidative damage, which was greatly increased under future environmental conditions. Digestive enzymatic activity of S. senegalensis larvae was also affected by future predictions. Hypercapnic conditions led to a decrease in the activity of digestive enzymes, both pancreatic (up to 26.1 % for trypsin and 74.5 % for amylase and intestinal enzymes (up to 36.1 % for alkaline phosphatase in post-metamorphic larvae. Moreover, the impact of ocean acidification and warming on some of these physiological and biochemical variables (namely, lower OCR and higher HSP and MDA levels were translated into larvae performance, being significantly correlated with decreased larval growth and survival or increased incidence of skeletal deformities. The increased vulnerability of flatfish early life stages under future ocean conditions is expected to potentially determine recruitment and population dynamics in marine ecosystems.

  7. Coral larvae move toward reef sounds

    NARCIS (Netherlands)

    Vermeij, M.J.A.; Marhaver, K.L.; Huijbers, C.M.; Nagelkerken, I.; Simpson, S.D.

    2010-01-01

    Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm) that influence settlement success are difficult to

  8. Planning to speak in L1 and L2.

    Science.gov (United States)

    Konopka, Agnieszka E; Meyer, Antje; Forest, Tess A

    2018-05-01

    The leading theories of sentence planning - Hierarchical Incrementality and Linear Incrementality - differ in their assumptions about the coordination of processes that map preverbal information onto language. Previous studies showed that, in native (L1) speakers, this coordination can vary with the ease of executing the message-level and sentence-level processes necessary to plan and produce an utterance. We report the first series of experiments to systematically examine how linguistic experience influences sentence planning in native (L1) speakers (i.e., speakers with life-long experience using the target language) and non-native (L2) speakers (i.e., speakers with less experience using the target language). In all experiments, speakers spontaneously generated one-sentence descriptions of simple events in Dutch (L1) and English (L2). Analyses of eye-movements across early and late time windows (pre- and post-400 ms) compared the extent of early message-level encoding and the onset of linguistic encoding. In Experiment 1, speakers were more likely to engage in extensive message-level encoding and to delay sentence-level encoding when using their L2. Experiments 2-4 selectively facilitated encoding of the preverbal message, encoding of the agent character (i.e., the first content word in active sentences), and encoding of the sentence verb (i.e., the second content word in active sentences) respectively. Experiment 2 showed that there is no delay in the onset of L2 linguistic encoding when speakers are familiar with the events. Experiments 3 and 4 showed that the delay in the onset of L2 linguistic encoding is not due to speakers delaying encoding of the agent, but due to a preference to encode information needed to select a suitable verb early in the formulation process. Overall, speakers prefer to temporally separate message-level from sentence-level encoding and to prioritize encoding of relational information when planning L2 sentences, consistent with

  9. Temporal and Spatial Distribution Patterns of Echinoderm Larvae in La Parguera, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Stacey M Williams

    2010-10-01

    Full Text Available This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64μm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval bundances, oblique tows were taken with 64 and 202μm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber and Asteroidea larvae (sea star accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (~24 day old D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64mm mesh net was more efficient for collection of echinoderm larvae than the 202mm mesh net. Rev. Biol. Trop. 58 (Suppl. 3: 81-88. Epub 2010 October 01.Este estudio describe patrones de abundancia temporal y espacial de larvas de

  10. Macroevolutionary interplay between planktic larvae and benthic predators

    Science.gov (United States)

    Peterson, Kevin J.

    2005-12-01

    Many marine invertebrates have a complex life cycle in which the egg develops into an intermediate planktic larval form rather than developing directly to the benthic juvenile stage. Because of the evolutionary and ecological complexity of pelagic-benthic life cycles, the reasons behind the origin of larvae and their subsequent maintenance over geological time are not well understood. Using both a molecular clock and the fossil record, I show that the initial exploitation of the predator-free pelagic realm by lecithotrophic larvae was achieved independently multiple times by the end of the Early Cambrian, and that the convergent evolution of planktotrophy from lecithotrophic ancestors evolved between the latest Cambrian and Middle Ordovician at least four, and possibly as many as eight, times. Both the exploitation of the pelagic realm by nonfeeding larvae and the acquisition of planktotrophy correlate in time with novel modes of benthic predation, including the dramatic rise in the number and type of epifaunal suspension feeders in the Early Ordovician.

  11. Identification of Ruffe larvae (Gymnocephalus cernuus) in the ...

    Science.gov (United States)

    Non-native Ruffe (Gymnocephalus cernua; family Percidae) were first detected in the Laurentian Great Lakes in 1986, and are not included in the Great Lakes larval fish key which was published several years prior to their discovery. In addition, subsequent scientific literature has inconsistently described Ruffe larvae. As a result, identification of larval Ruffe remains challenging. We used traditional morphology paired with DNA technology to develop diagnostics for Ruffe larvae collected in the lower St. Louis River, and compared them to similar species. Ruffe < 6 mm total length have myomere counts and a phenotype that more closely resemble centrarchids like Black Crappie, Bluegill and Pumpkinseed rather than percids. However, morphometrics and pigment patterns can be used to distinguish Ruffe from similar centrarchids at this size. As Ruffe larvae develop, they increasingly resemble other percids such as Yellow Perch, but can be distinguished using myomere counts and morphological features. The findings presented here clarify conflicting descriptions in the scientific literature, and provide additional data to support more confident morphological identification of larval Ruffe. The impact of invasive Ruffe (Gymnocephalus cernuus) on the ecology of Great Lakes systems is currently being studied. Reproduction and early life history data, however, may be hampered by a general lack of information regarding their early life stage morphological description.

  12. Nutritional Transition Period in Early Larvae Clarias Gariepinus

    International Nuclear Information System (INIS)

    Ing, N.S.; Chew, H.H.

    2015-01-01

    The nutritional transition period of Clarias gariepinus were described based on the early development from hatching to 120 hours after hatching (hAH) reared at 27.5 - 28.6 degree Celsius. Newly hatched larvae had a large greenish yolk sac volume (0.99 ± 0.31 mm 3 ) located below a straight undeveloped digestive tract, mouth not opened, eyes unpigmented and the larvae lie on the bottom of rearing tank. During endogenous feeding period, the larval feeding system has developed rapidly with development oesophagus. Yolk sac were not completely depleted at the onset of exogenous feeding (36 hAH, 0.19 ± 0.11 mm 3 ), and a period of mixed nutrition was observed up to 68 hAH when yolk was completely exhausted. Yolk sac volume was significantly different by time at hatching, 6, 12 and 18 to 36 hAH (ANOVA, P<0.05). At 36 hAH, the larvae commenced feeding once morphologically developed with opened anus, functional jaw and intestine, and demonstrated horizontally swimming. The rudimentary chemoreceptors like olfactory organs and taste buds that were found on the barbels and oral cavity assisted in food detection and commenced feeding without vision. Due to the cannibalistic behaviour at early stage, feed are suggested to be provided during 36 hAH and avoided delay feeding in the larval rearing. (author)

  13. Quantitative Profiling Identifies Potential Regulatory Proteins Involved in Development from Dauer Stage to L4 Stage in Caenorhabditis elegans.

    Science.gov (United States)

    Kim, Sunhee; Lee, Hyoung-Joo; Hahm, Jeong-Hoon; Jeong, Seul-Ki; Park, Don-Ha; Hancock, William S; Paik, Young-Ki

    2016-02-05

    When Caenorhabditis elegans encounters unfavorable growth conditions, it enters the dauer stage, an alternative L3 developmental period. A dauer larva resumes larval development to the normal L4 stage by uncharacterized postdauer reprogramming (PDR) when growth conditions become more favorable. During this transition period, certain heterochronic genes involved in controlling the proper sequence of developmental events are known to act, with their mutations suppressing the Muv (multivulva) phenotype in C. elegans. To identify the specific proteins in which the Muv phenotype is highly suppressed, quantitative proteomic analysis with iTRAQ labeling of samples obtained from worms at L1 + 30 h (for continuous development [CD]) and dauer recovery +3 h (for postdauer development [PD]) was carried out to detect changes in protein abundance in the CD and PD states of both N2 and lin-28(n719). Of the 1661 unique proteins identified with a proteomic approach identifies and quantitates the regulatory proteins potentially involved in PDR in C. elegans, which safeguards the overall lifecycle in response to environmental changes.

  14. Greedy vs. L1 Convex Optimization in Sparse Coding

    DEFF Research Database (Denmark)

    Ren, Huamin; Pan, Hong; Olsen, Søren Ingvor

    Sparse representation has been applied successfully in many image analysis applications, including abnormal event detection, in which a baseline is to learn a dictionary from the training data and detect anomalies from its sparse codes. During this procedure, sparse codes which can be achieved...... and action recognition, a comparative study of codes in abnormal event detection is less studied and hence no conclusion is gained on the effect of codes in detecting abnormalities. We constrict our comparison in two types of the above L0-norm solutions: greedy algorithms and convex L1-norm solutions....... Considering the property of abnormal event detection, i.e., only normal videos are used as training data due to practical reasons, effective codes in classification application may not perform well in abnormality detection. Therefore, we compare the sparse codes and comprehensively evaluate their performance...

  15. TV-L1 optical flow for vector valued images

    DEFF Research Database (Denmark)

    Rakêt, Lars Lau; Roholm, Lars; Nielsen, Mads

    2011-01-01

    . The resulting algorithms have the same degree of parallelism as the case of one-dimensional images, and we have produced an efficient GPU implementation, that can take vector valued images with vectors of any dimension. Finally we demonstrate how these algorithms generally produce better flows than the original...... with the total variation (TV) regular- ization that smoothes the flow, but preserve strong discontinuities such as edges. Specifically the approach of Zach et al. [1] has provided a very clean and efficient algorithm for calculating TV-L1 optical flows between grayscale images. In this paper we propose...... a generalized algorithm that works on vector valued images, by means of a generalized projection step. We give examples of calculations of flows for a number of multi- dimensional constancy assumptions, e.g. gradient and RGB, and show how the developed methodology expands to any kind of vector valued images...

  16. The Antigenic Structure Characterization of Oestrus Ovis Larvae

    Directory of Open Access Journals (Sweden)

    Daniela Moţ

    2012-05-01

    Full Text Available With the aim of proteic components definition from Oestrus ovis larvae, endowed with antigenic properties, able to induce immune responses in vivo and to react in vitro with induced molecular effectors were been performed: electrophoresis in poliacrilamid gel, western blot technique preceded by immunotransfer, immunoassay test. Total soluble larval antigens of O. ovis were been prepared through ultrasonic disintegration, from all three larval stages. Western blot technique allowed and emphasized the specific antigens with a superior sensitivity in comparison with SDS-PAGE electrophoresis. After antigenic characteristics demonstration of investigated larval antigens were been performed the immunoassay test to emphasized the antibodies dozes for O. ovis infestation diagnosis.

  17. Whole-body gene expression pattern registration in Platynereis larvae.

    Science.gov (United States)

    Asadulina, Albina; Panzera, Aurora; Verasztó, Csaba; Liebig, Christian; Jékely, Gáspár

    2012-12-03

    Digital anatomical atlases are increasingly used in order to depict different gene expression patterns and neuronal morphologies within a standardized reference template. In evo-devo, a discipline in which the comparison of gene expression patterns is a widely used approach, such standardized anatomical atlases would allow a more rigorous assessment of the conservation of and changes in gene expression patterns during micro- and macroevolutionary time scales. Due to its small size and invariant early development, the annelid Platynereis dumerilii is particularly well suited for such studies. Recently a reference template with registered gene expression patterns has been generated for the anterior part (episphere) of the Platynereis trochophore larva and used for the detailed study of neuronal development. Here we introduce and evaluate a method for whole-body gene expression pattern registration for Platynereis trochophore and nectochaete larvae based on whole-mount in situ hybridization, confocal microscopy, and image registration. We achieved high-resolution whole-body scanning using the mounting medium 2,2'-thiodiethanol (TDE), which allows the matching of the refractive index of the sample to that of glass and immersion oil thereby reducing spherical aberration and improving depth penetration. This approach allowed us to scan entire whole-mount larvae stained with nitroblue tetrazolium/5-bromo-4-chloro-3-indolyl phosphate (NBT/BCIP) in situ hybridization and counterstained fluorescently with an acetylated-tubulin antibody and the nuclear stain 4'6-diamidino-2-phenylindole (DAPI). Due to the submicron isotropic voxel size whole-mount larvae could be scanned in any orientation. Based on the whole-body scans, we generated four different reference templates by the iterative registration and averaging of 40 individual image stacks using either the acetylated-tubulin or the nuclear-stain signal for each developmental stage. We then registered to these templates the

  18. Whole-body gene expression pattern registration in Platynereis larvae

    Directory of Open Access Journals (Sweden)

    Asadulina Albina

    2012-12-01

    stage. We then registered to these templates the expression patterns of cell-type specific genes. In order to evaluate the gene expression pattern registration, we analyzed the absolute deviation of cell-center positions. Both the acetylated-tubulin- and the nuclear-stain-based templates allowed near-cellular-resolution gene expression registration. Nuclear-stain-based templates often performed significantly better than acetylated-tubulin-based templates. We provide detailed guidelines and scripts for the use and further expansion of the Platynereis gene expression atlas. Conclusions We established whole-body reference templates for the generation of gene expression atlases for Platynereis trochophore and nectochaete larvae. We anticipate that nuclear-staining-based image registration will be applicable for whole-body alignment of the embryonic and larval stages of other organisms in a similar size range.

  19. Correlations of age and growth rate with microbiota composition in Atlantic cod (Gadus morhua) larvae.

    Science.gov (United States)

    Trinh, Ly T T; Bakke, Ingrid; Vadstein, Olav

    2017-08-17

    Little information is available on the link between host development (growth rate and ontogeny) and the composition of the microbiota in fish larvae. This study was carried out to examine potential correlations of microbiota composition with age and growth rate of Atlantic cod larvae. Small and large cod larvae of the same age, representing slow and fast growing individuals, were sampled 10 times during a period of 42 days post hatching (dph), and the composition of the larval microbiota was investigated using a PCR/DGGE (Denaturing Gradient Gel Electrophoresis) strategy. We found significant differences in the intestinal microbiota of small and large larvae of the same age for 4 of the 10 age stages studied. We further found that the variation in the composition of the larval microbiota was more strongly correlated to age than to growth rate for larvae up to 28 dph, whereas for the older larvae growth rate and age was equally correlated to the composition of the microbiota. These results indicate that larval development may structure the microbiota through a change in selection pressure due to host-microbe and microbe-microbe interactions, and that the composition of the microbiota may influence larval development through improved energy gain.

  20. On chip cryo-anesthesia of Drosophila larvae for high resolution in vivo imaging applications.

    Science.gov (United States)

    Chaudhury, Amrita Ray; Insolera, Ryan; Hwang, Ran-Der; Fridell, Yih-Woei; Collins, Catherine; Chronis, Nikos

    2017-06-27

    We present a microfluidic chip for immobilizing Drosophila melanogaster larvae for high resolution in vivo imaging. The chip creates a low-temperature micro-environment that anaesthetizes and immobilizes the larva in under 3 minutes. We characterized the temperature distribution within the chip and analyzed the resulting larval body movement using high resolution fluorescence imaging. Our results indicate that the proposed method minimizes submicron movements of internal organs and tissue without affecting the larva physiology. It can be used to continuously immobilize larvae for short periods of time (minutes) or for longer periods (several hours) if used intermittently. The same chip can be used to accommodate and immobilize arvae across all developmental stages (1st instar to late 3rd instar), and loading larvae onto the chip does not require any specialized skills. To demonstrate the usability of the chip, we observed mitochondrial trafficking in neurons from the cell bodies to the axon terminals along with mitochondrial fusion and neuro-synaptic growth through time in intact larvae. Besides studying sub-cellular processes and cellular development, we envision the use of on chip cryo-anesthesia in a wide variety of biological in vivo imaging applications, including observing organ development of the salivary glands, fat bodies and body-wall muscles.

  1. AKTIVITAS INSEKTISIDA BAGIAN TUMBUHAN CALOPHYLLUM SOULTTRI BURM.F. (CLU IACEAE TERHADAP LARVA LEPIDOPTERA

    Directory of Open Access Journals (Sweden)

    Edy Syahputra

    2014-08-01

    Full Text Available The objective of this test was evaluate the insecticidal activity of ectract of some parts of Calophyllum soulattri (Clusiaceae against larvae of three species of Lepidoptera, i. e Crocidolomia pavonana, Plutella xylostela, and Pieris sp.. Extraction of plant materials was done by infusion method using ethanol. The bioassays were conducted by leaf-feeding method. Second-instar larvae were fed extract-treated broccoli leaves of 48 hours, then they were presented with untreated leaves until the surviving larvae larvae reached the fourth-instar stage. The number of dead larvae was recorded daily an larval mortality date were analyzed by probit method. The result showed the gummy bark exudates and bark extract of old and young C. soulattri plants were highly active against C. pavonana. The abrk extact of old C. soulattri plant was also effective against P. xilostella and Pieris sp. The gummy exudates possessed strong insecticidal activity against C. pavonana larvae with LC50 of 0.04% and prolonged the developmental time from second to fourth instar of C. soulattri 2.03-7.25 days compared with control. The bark excudate gave positive respon to alkaloid flavonoid, and tannin test. Futher studies are needed to identify insecticidal compound in those active extracts.

  2. [Observations on the larvae of the tropical marine crab Petrolisthes armatus in the Gulf of Nicoya, Costa Rica].

    Science.gov (United States)

    Díaz-Ferguson, Edgardo; Arroyo, Daisy; Morales, Alvaro; Vargas, José A

    2008-09-01

    During October and November 1998 (rainy season), and December, February and March 1999 (dry season), larvae distribution of Petrolisthes armatus and associated decapods were sampled in three different sites at the Punta Morales peninsula, Gulf of Nicoya, Costa Rica. A total of 6014 decapod larvae were collected, and 73 belonged to the genus Petrolisthes spp. No significant total larval density differences were found between seasons (p > 0.05); but there was a greater density of P. armatus and other decapod larvae (p > 0.05) during the dry season. In addition, no significant variations on temperature and oxygen concentration were observed. P. armatus larval abundance was higher during low tide, in contrast with other decapod larvae. Significant differences among sites were found for other decapod larvae, but not for P. armatus. The only parameter that varied significantly between seasons was salinity and results demonstrate that this factor regulates temporal concentration of larvae. Moreover, flow-tide oscillations were the most important spatial factor in larval dynamics. We propose this mechanism: P. armatus liberates larvae during high tide; these larvae leave the coastal area during low tide and return to the rocky intertidal ecosystem during high tide, when they are ready to settle as megalopa (pre-juvenile stage). Parallel laboratory observations showed higher survival rates at lower salinities (15 ups against 35 ups) and that the duration of the period from zoea I to megalopa was, in average, 19 days.

  3. Cross-modal working memory binding and L1-L2 word learning.

    Science.gov (United States)

    Wang, Shinmin; Allen, Richard J; Fang, Shin-Yi; Li, Ping

    2017-11-01

    The ability to create temporary binding representations of information from different sources in working memory has recently been found to relate to the development of monolingual word recognition in children. The current study explored this possible relationship in an adult word-learning context. We assessed whether the relationship between cross-modal working memory binding and lexical development would be observed in the learning of associations between unfamiliar spoken words and their semantic referents, and whether it would vary across experimental conditions in first- and second-language word learning. A group of English monolinguals were recruited to learn 24 spoken disyllable Mandarin Chinese words in association with either familiar or novel objects as semantic referents. They also took a working memory task in which their ability to temporarily bind auditory-verbal and visual information was measured. Participants' performance on this task was uniquely linked to their learning and retention of words for both novel objects and for familiar objects. This suggests that, at least for spoken language, cross-modal working memory binding might play a similar role in second language-like (i.e., learning new words for familiar objects) and in more native-like situations (i.e., learning new words for novel objects). Our findings provide new evidence for the role of cross-modal working memory binding in L1 word learning and further indicate that early stages of picture-based word learning in L2 might rely on similar cognitive processes as in L1.

  4. SWATCH: common control SW for the uTCA-based upgraded CMS L1 Trigger

    Science.gov (United States)

    Brooke, Jim; Bunkowski, Karol; Cali, Ivan; Ghabrous Larrea, Carlos; Lazaridis, Christos; Thea, Alessandro

    2015-12-01

    The CMS L1 Trigger electronics are composed of a large number of different cards based on the VMEBus standard. The majority of the system is being replaced to adapt the trigger to the higher collision rates the LHC will deliver after the LS1, the first phase on the CMS upgrade program. As a consequence, the software that controls, monitors and tests the hardware will need to be re-written. The upgraded trigger will consist of a set of general purpose boards of similar technology that follow the TCA specification, thus resulting in a more homogeneous system. A great effort has been made to identify the common firmware blocks and components shared across different cards, regardless of the role they play within the trigger data path. A similar line of work has been followed in order to identify all possible common functionalities in the control software, as well as in the database where the hardware initialisation and configuration data are stored. This will not only increase the homogeneity on the software and database sides, but it will also reduce the manpower needed to accommodate the online SW to the changes on hardware. Due to the fact that the upgrade will take place in different stages, it has been taken into consideration that these new components had to be integrated in the current SW framework. This paper presents the design of the control SW and configuration database for the upgraded L1 Trigger.

  5. SWATCH: common control SW for the uTCA-based upgraded CMS L1 Trigger

    International Nuclear Information System (INIS)

    Brooke, Jim; Bunkowski, Karol; Cali, Ivan; Larrea, Carlos Ghabrous; Lazaridis, Christos; Thea, Alessandro

    2015-01-01

    The CMS L1 Trigger electronics are composed of a large number of different cards based on the VMEBus standard. The majority of the system is being replaced to adapt the trigger to the higher collision rates the LHC will deliver after the LS1, the first phase on the CMS upgrade program. As a consequence, the software that controls, monitors and tests the hardware will need to be re-written. The upgraded trigger will consist of a set of general purpose boards of similar technology that follow the TCA specification, thus resulting in a more homogeneous system. A great effort has been made to identify the common firmware blocks and components shared across different cards, regardless of the role they play within the trigger data path. A similar line of work has been followed in order to identify all possible common functionalities in the control software, as well as in the database where the hardware initialisation and configuration data are stored. This will not only increase the homogeneity on the software and database sides, but it will also reduce the manpower needed to accommodate the online SW to the changes on hardware. Due to the fact that the upgrade will take place in different stages, it has been taken into consideration that these new components had to be integrated in the current SW framework. This paper presents the design of the control SW and configuration database for the upgraded L1 Trigger. (paper)

  6. Validation of Code ASTEC with LIVE-L1 Experimental Results

    International Nuclear Information System (INIS)

    Bachrata, Andrea

    2008-01-01

    The severe accidents with core melting are considered at the design stage of project at Generation 3+ of Nuclear Power Plants (NPP). Moreover, there is an effort to apply the severe accident management to the operated NPP. The one of main goals of severe accidents mitigation is corium localization and stabilization. The two strategies that fulfil this requirement are: the in-vessel retention (e.g. AP-600, AP- 1000) and the ex-vessel retention (e.g. EPR). To study the scenario of in-vessel retention, a large experimental program and the integrated codes have been developed. The LIVE-L1 experimental facility studied the formation of melt pools and the melt accumulation in the lower head using different cooling conditions. Nowadays, a new European computer code ASTEC is being developed jointly in France and Germany. One of the important steps in ASTEC development in the area of in-vessel retention of corium is its validation with LIVE-L1 experimental results. Details of the experiment are reported. Results of the ASTEC (module DIVA) application to the analysis of the test are presented. (author)

  7. Transcriptome profiling of individual larvae of two different developmental modes in the poecilogonous polychaete Streblospio benedicti (Spionidae).

    Science.gov (United States)

    Marsh, Adam G; Fielman, Kevin T

    2005-05-15

    Understanding the range of biochemical and physiological phenotypes in a cohort of embryos or larvae is crucial to understanding the lifespan, dispersal potential, and recruitment success of the early life history stages of a species. In this study, a novel kinetic assay has been employed to profile the transcriptome pool complexity in individual larvae of both planktotrophic and lecithotrophic developmental modes in the poecilogonous polycheate Streblospio benedicti. Using a nano-scale synthesis strategy, the mRNA pool in a single embryo or larva can be amplified into cDNA for quantitative characterization in a high-throughput, kinetic reannealing assay in a 96-well, microtiterplate format. This assay generates transcript-pool complexity estimates at 1 degrees C temperature increments for each sample producing 3,360 quantitative measurements per 96-well plate. Measuring transcriptome complexity on 8 individual planktotrophic and 8 individual lecithotrophic larvae (with 4 duplicate assays for each individual) reveals a more complex gene expression profile in planktotrophic larvae and a lower level of interindividual variation in expression patterns in lecithotrophic larvae. Although differences in these gene expression patterns are more likely due to physiological differences between feeding and non-feeding larval types in these late-stage individuals, this is one of the first assessments of inter-individual variation in gene expression patterns in marine invertebrate larvae and indicates a large potential for developmental variability. Copyright 2005 Wiley-Liss, Inc

  8. Larvae of the pycnogonids Ammothea gigantea Gordon, 1932 and Achelia cuneatis Child, 1999 described from archived specimens

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2012-12-01

    Full Text Available The larvae of two species of Pycnogonida are described from archived collections. Achelia cuneatis Child, 1999 is an example of a typical protonymphon larva in having three pairs of three segmented appendages, cheliphores, palps and ovigerous appendages. Ammothea gigantea Gordon, 1932 is an example of a lecithotrophic protonymphon larva, having the three pair of appendages plus buds of the first walking legs. Ammothea gigantea is the third species known to have this larval type. The Achelia cuneatis protonymphon larvae is oval, 150 um long and characterized by a relatively long spinneret spine arising at the distal end of the first segment of each cheliphore. Spines also arise from the distal end of the first segment of the second and third limbs. This typical protonymphon larva of Achelia cuneatis has few yolk granules. The lecithotrophic protonymphon of Ammothea gigantea lacks a spinneret spine on the cheliphore; the larva is oval in shape, but much larger than Achelia cuneatis with a length of 700 um. Its second limb is much larger than the third limb on the first post-embryonic stage, and the third limb is further reduced to a spine-like structure on the second post-embryonic stage. This lecithotrophic protonymphon larva has a large number of yolk granules.

  9. Clash of kingdoms or why Drosophila larvae positively respond to fungal competitors

    Directory of Open Access Journals (Sweden)

    Rohlfs Marko

    2005-01-01

    Full Text Available Abstract Background Competition with filamentous fungi has been demonstrated to be an important cause of mortality for the vast group of insects that depend on ephemeral resources (e.g. fruit, dung, carrion. Recent data suggest that the well-known aggregation of Drosophila larvae across decaying fruit yields a competitive advantage over mould, by which the larvae achieve a higher survival probability in larger groups compared with smaller ones. Feeding and locomotor behaviour of larger larval groups is assumed to cause disruption of fungal hyphae, leading to suppression of fungal growth, which in turn improves the chances of larval survival to the adult stage. Given the relationship between larval density, mould suppression and larval survival, the present study has tested whether fungal-infected food patches elicit communal foraging behaviour on mould-infected sites by which larvae might hamper mould growth more efficiently. Results Based on laboratory experiments in which Drosophila larvae were offered the choice between fungal-infected and uninfected food patches, larvae significantly aggregated on patches containing young fungal colonies. Grouping behaviour was also visible when larvae were offered only fungal-infected or only uninfected patches; however, larval aggregation was less strong under these conditions than in a heterogeneous environment (infected and uninfected patches. Conclusion Because filamentous fungi can be deadly competitors for insect larvae on ephemeral resources, social attraction of Drosophila larvae to fungal-infected sites leading to suppression of mould growth may reflect an adaptive behavioural response that increases insect larval fitness and can thus be discussed as an anti-competitor behaviour. These observations support the hypothesis that adverse environmental conditions operate in favour of social behaviour. In a search for the underlying mechanisms of communal behaviour in Drosophila, this study highlights

  10. Expression of PD-L1 on canine tumor cells and enhancement of IFN-γ production from tumor-infiltrating cells by PD-L1 blockade.

    Directory of Open Access Journals (Sweden)

    Naoya Maekawa

    Full Text Available Programmed death 1 (PD-1, an immunoinhibitory receptor, and programmed death ligand 1 (PD-L1, its ligand, together induce the "exhausted" status in antigen-specific lymphocytes and are thus involved in the immune evasion of tumor cells. In this study, canine PD-1 and PD-L1 were molecularly characterized, and their potential as therapeutic targets for canine tumors was discussed. The canine PD-1 and PD-L1 genes were conserved among canine breeds. Based on the sequence information obtained, the recombinant canine PD-1 and PD-L1 proteins were constructed; they were confirmed to bind each other. Antibovine PD-L1 monoclonal antibody effectively blocked the binding of recombinant PD-1 with PD-L1-expressing cells in a dose-dependent manner. Canine melanoma, mastocytoma, renal cell carcinoma, and other types of tumors examined expressed PD-L1, whereas some did not. Interestingly, anti-PD-L1 antibody treatment enhanced IFN-γ production from tumor-infiltrating cells. These results showed that the canine PD-1/PD-L1 pathway is also associated with T-cell exhaustion in canine tumors and that its blockade with antibody could be a new therapeutic strategy for canine tumors. Further investigations are needed to confirm the ability of anti-PD-L1 antibody to reactivate canine antitumor immunity in vivo, and its therapeutic potential has to be further discussed.

  11. Neurocognitive Development and Predictors of L1 and L2 Literacy Skills in Dyslexia: A Longitudinal Study of Children 5-11 Years Old.

    Science.gov (United States)

    Helland, Turid; Morken, Frøydis

    2016-02-01

    The aim of this study was to find valid neurocognitive precursors of literacy development in first language (L1, Norwegian) and second language (L2, English) in a group of children during their Pre-literacy, Emergent Literacy and Literacy stages, by comparing children with dyslexia and a typical group. Children who were 5 years old at project start were followed until the age of 11, when dyslexia was identified and data could be analysed in retrospect. The children's neurocognitive pattern changed both by literacy stage and domain. Visuo-spatial recall and RAN appeared as early precursors of L1 literacy, while phonological awareness appeared as early precursor of L2 English. Verbal long term memory was associated with both L1 and L2 skills in the Literacy stage. Significant group differences seen in the Pre-literacy and Emergent literacy stages decreased in the Literacy stage. The developmental variations by stage and domain may explain some of the inconsistencies seen in dyslexia research. Early identification and training are essential to avoid academic failure, and our data show that visuo-spatial memory and RAN could be suitable early markers in transparent orthographies like Norwegian. Phonological awareness was here seen as an early precursor of L2 English, but not of L1 Norwegian. © 2015 The Authors. Dyslexia published by John Wiley & Sons Ltd.

  12. Neurocognitive Development and Predictors of L1 and L2 Literacy Skills in Dyslexia: A Longitudinal Study of Children 5–11 Years Old

    Science.gov (United States)

    Morken, Frøydis

    2015-01-01

    The aim of this study was to find valid neurocognitive precursors of literacy development in first language (L1, Norwegian) and second language (L2, English) in a group of children during their Pre‐literacy, Emergent Literacy and Literacy stages, by comparing children with dyslexia and a typical group. Children who were 5 years old at project start were followed until the age of 11, when dyslexia was identified and data could be analysed in retrospect. The children's neurocognitive pattern changed both by literacy stage and domain. Visuo‐spatial recall and RAN appeared as early precursors of L1 literacy, while phonological awareness appeared as early precursor of L2 English. Verbal long term memory was associated with both L1 and L2 skills in the Literacy stage. Significant group differences seen in the Pre‐literacy and Emergent literacy stages decreased in the Literacy stage. The developmental variations by stage and domain may explain some of the inconsistencies seen in dyslexia research. Early identification and training are essential to avoid academic failure, and our data show that visuo‐spatial memory and RAN could be suitable early markers in transparent orthographies like Norwegian. Phonological awareness was here seen as an early precursor of L2 English, but not of L1 Norwegian. © 2015 The Authors. Dyslexia published by John Wiley & Sons Ltd. PMID:26511662

  13. Dynamic morphology of fish larvae, structural implications of friction forces in swimming, feeding and ventilation

    NARCIS (Netherlands)

    Osse, J.W.M.; Boogaart, van den J.G.M.

    1999-01-01

    Dynamic morphology is the study of the ontogenetic transformations of functional systems in growing organisms. This paper describes these processes in fish larvae as they grow into the juvenile stage. Details of form changes and growth at the level of the organism and its organs are given. Some

  14. Acute toxicity of chlorpyrifos to embryo and larvae of banded gourami Trichogaster fasciata

    NARCIS (Netherlands)

    Sumon, Kizar Ahmed; Saha, Sampa; Brink, van den Paul J.; Peeters, Edwin T.H.M.; Bosma, Roel H.; Rashid, Harunur

    2017-01-01

    This study elucidated the acute toxicity of chlorpyrifos on the early life stages of banded gourami (Trichogaster fasciata). To determine the acute effects of chlorpyrifos on their survival and development, we exposedthe embryos and two-day-old larvae to six concentrations (0, 0.01, 0.10, 1.0, 10

  15. Immunomodulatory effects of excretory/secretory compounds from Contracaecum osculatum larvae in a zebrafish inflammation model

    DEFF Research Database (Denmark)

    Mehrdana, Foojan; Kania, Per Walter; Nazemi, Sasan

    2017-01-01

    Excretory/secretory (ES) compounds isolated from third-stage larvae of the anisakid nematode Contracaecum osculatum parasitizing liver of Baltic cod were investigated for effects on immune gene expression in a zebrafish LPS-induced inflammation model. ES products containing a series of proteins, ...

  16. A freak twin trilobite larva of the Indian horseshoe crab Tachypleus gigas (Muller)

    Digital Repository Service at National Institute of Oceanography (India)

    Mishra, J.K.; Chatterji, A.; Parulekar, A.H.

    Early embryonic stages of a horseshoe crab Tachypleus gigas were studied using micrographs of live embryo. A freak egg showing two trilobite larvae bridged with each other was noticed on 38th day after fertilization. Morphology of this egg has been...

  17. Aras kerusakan ekonomi (AKE larva Ostrinia furnacalis (Lepidoptera: Crambidae pada tiga fase pertumbuhan tanaman jagung

    Directory of Open Access Journals (Sweden)

    Subiadi Subiadi

    2015-09-01

    Full Text Available The Asian corn borer, Ostrinia furnacalis (Guenée is an important economic pest of corn and is widely distributed in the Asia-Pacific region, including Indonesia. The objective of this research is to investigate the effect of infestation levels of O. furnacalis larvae per plant on corn grain yield reductions, and to determine economic injury levels (EIL of O. furnacalis larvae at three growth stages (V10, R1, and R2 of corn. The experiment was designed in a split-plot randomized complete block with blocks replicated three times. Differences in grain weight between the uninfested and highest infestation levels (six larvae per plant V10, R1, and R2 were 59.81; 58.76; and 49.20 g/plant, respectively. For each additional infestation by one larvae per plant at V10, R1, dan R2, there is reduction in grain weight of 4.94%, 4.56% and 3.76% respectively. The calculation of EILs was based on the proportion of yield loss per larvae per plant on three corn growth stages with the assumption that pesticide control reduced 67% of O. furnacalis population. The lowest EIL was 0.31 larvae per plant at V10 when the cost of control reaching Rp.125,000 per ha and crop value of Rp.12,000,000 per ha. The highest EIL of 1.24 larvae per plant was found at R2 with the cost of control of Rp.250,000 per ha and crop value of Rp.8,000,000 per ha.

  18. Plastic deformation mechanisms in a crept L1{sub 2} hardened Co-base superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Pyczak, F., E-mail: florian.pyczak@hzg.de [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Bauer, A.; Göken, M.; Neumeier, S. [Department of Materials Science and Engineering, Institute I, University Erlangen-Nürnberg, 91058 Erlangen (Germany); Lorenz, U.; Oehring, M.; Schell, N.; Schreyer, A.; Stark, A. [Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Symanzik, F. [Helmut-Schmidt-University, 22008 Hamburg (Germany)

    2013-06-01

    Plastic deformation mechanisms in a crept L1{sub 2} hardened Co-base superalloy are investigated by transmission electron microscopy. The deformation happens mainly in the cobalt solid solution matrix by slip of ordinary a/2〈101〉{111} dislocations and rafting of the γ′ precipitates perpendicular to the external compressive stress axis is observed. Dislocation structures are early stages of the development of γ/γ′ interfacial dislocation networks. Furthermore, γ′ precipitates are sheared by partial dislocations generating stacking faults which sometimes extend over matrix channels and neighbouring γ′ precipitates. Due to the positive lattice mismatch at creep temperature the dislocation activity in matrix channels perpendicular to the compressive external stress axis is less pronounced compared to parallel channels.

  19. Liberating literacies: L1-students resources for stance-taking in the literature classroom

    DEFF Research Database (Denmark)

    Kabel, Kristine; Brok, Lene Storgaard

    2015-01-01

    Keywords: Reflection literacy, students’ meaning-making resources, literature education, lower secondary school, qualitative case studies Making aspects of privileged ways of participating visible is central to supporting students’ literacy development within different disciplines. However......, educational linguistics and literacy studies on students’ meaning-making resources in lower secondary school indicate that some significant resources within L1 at this stage of schooling are often part of an invisible curriculum (Christie, 2012; Folkeryd, 2007; Macken-Horarik,1996,2006; Penne, 2006......) and their resources for negotiation and collaboration (Year 5). The purpose of both studies is to develop a metalanguage adequate to characterize interpersonal aspects of students’ actual meaning-making resources, a metalanguage that can support discussions of privileged ways of participating and of co-constructing L...

  20. Apolipoprotein L1 Gene Effects on Kidney Transplantation.

    Science.gov (United States)

    Freedman, Barry I; Locke, Jayme E; Reeves-Daniel, Amber M; Julian, Bruce A

    2017-11-01

    The pathogenesis of many common etiologies of nephropathy has been informed by recent molecular genetic breakthroughs. It now is apparent that the ethnic disparity in the risk for nondiabetic chronic kidney disease between African Americans and European Americans is explained largely by variation in the apolipoprotein L1 gene (APOL1). The presence of two APOL1 renal risk variants markedly increases an individual's risk for kidney disease. In transplantation, kidneys from deceased African Americans with two APOL1 renal risk variants have shorter survival intervals after engraftment, regardless of the ethnicity of the recipient. Precision medicine will transform the clinical practice of nephrology and kidney transplantation, and play an important role in the allocation of kidneys from deceased and living kidney donors with recent African ancestry. This article reviews existing data on APOL1 in deceased-donor and living-donor kidney transplantation. It considers the impact of including APOL1 genotyping in decisions on the allocation and discard of deceased-donor kidneys, as well as the selection of living donors. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. On Recursive Modification in Child L1 French

    Directory of Open Access Journals (Sweden)

    Yves Roberge

    2018-03-01

    Full Text Available This paper investigates nominal recursive modification (RM in the L1 acquisition of French. Although recursion is considered the fundamental property of human languages, recursive self-embedding is found to be difficult for children in a variety of languages and constructions. Despite these challenges, the acquisition of RM proves to be resilient; acquirable even under severely degraded input conditions. From a minimalist perspective on the operations of narrow syntax, recursive embedding is essentially the application of a sequence of Merge operations (Chomsky 1995; Trotzke and Zwart 2014; therefore, given the universality of Merge, we do not expect to find cross-linguistic differences in how difficult recursion is. But if the challenging nature of recursion stems from factors which might differ from language to language, we expect different outcomes cross-linguistically. We compare new data from French to existing English data (Pérez-Leroux et al. 2012 in order to examine to what extent language-specific properties of RM structures determine the acquisition path. While children’s production differs significantly from their adult’s counterparts, we find no differences between French-speaking and English-speaking children. Our findings suggest that the challenging nature of recursion does not stem from the grammar itself and that what shapes the acquisition path is the interaction between universal properties of language and considerations not specific to language, namely computational efficiency.

  2. Occurrence of entomopathogenic fungi and parasitic nematodes on Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae collected in Central Chiapas, Mexico

    Science.gov (United States)

    Fall armyworm larvae (FAW), Spodoptera frugiperda (J. E. Smith) were collected from whorl-stage cornfields, between the V2 and V4 stages, in 22 localities of Central, Chiapas, México, called "La Frailesca" during late June 2009 to determine the occurrence of native entomopathogens and parasitic nema...

  3. Exfoliation of the epidermal cells and defecation by amphibian larvae in response to coelomic fluid and lysenin from the earthworm Eisenia foetida.

    Science.gov (United States)

    Kobayashi, Hideshi; Suzuki, Hirohumi; Ohta, Naoshi

    2006-08-01

    Coelomic fluid (CF) and lysenin from the earthworm Eisenia foetida induced heavy epidermal exfoliation in the larvae of Bufo japonicus formosus at developmental stages from hatching (stage 22) to operculum completion (stage 34). In experiments with Xenopus laevis, we observed that exfoliated cells were not stained by trypan blue. Thus, it appeared that these cells were still alive. It is likely, therefore, that both CF and lysenin might disrupt the adhesion between epidermal cells of larvae prior to stage 34. Since it is known that lysenin exerts its toxic effects through its specific binding to sphingomyelin (SM), SM might be involved in such adhesion. This hypothesis was supported by the observations that CF and lysenin which had been incubated with SM-liposomes lost their exfoliative activity. In larvae after stage 34, the mechanism of adhesion between epidermal cells seemed to change and the adhesion was no longer disrupted by CF and lysenin. In larvae at around stage 34, a collagen layer started to form beneath the basement membrane of the epidermis. Furthermore, larvae at around this stage started to eat solid food. The developing collagen layer and food intake might be related indirectly to the chemical change in epidermal adhesion. The induction of exfoliation by CF and lysenin was also observed in other amphibian species. In Bufo larvae, defecation was induced both by CF and by lysenin but this effect was independent of exfoliation.

  4. Development of phonological awareness in English-Mandarin bilinguals: a comparison of English-L1 and Mandarin-L1 kindergarten children.

    Science.gov (United States)

    Yeong, Stephanie H M; Rickard Liow, Susan J

    2012-06-01

    Phoneme awareness is critical for literacy acquisition in English, but relatively little is known about the early development of phonological awareness in ESL (English as a second language) bilinguals when their two languages have different phonological structures. Using parallel tasks in English and Mandarin, we tracked the development of L1 (first language) and L2 (second language) syllable and phoneme awareness longitudinally in English-L1 and Mandarin-L1 prereaders (n=70, 4- and 5-year-olds) across three 6-month intervals. In English, the English-L1 children's performance was better in phoneme awareness at all three time points, but the Mandarin-L1 children's syllable awareness was equivalent to the English-L1 children's syllable awareness by Time 3. In Mandarin, the English-L1 children's phoneme awareness, but not their syllable awareness, was also significantly better than that of the Mandarin-L1 children at all three time points. Cross-lagged correlations revealed that only the English-L1 children applied their L1 syllable and phoneme awareness to their L2 (Mandarin) processing by Time 2 and that the Mandarin-L1 children seemed to require exposure to English (L2) before they developed phoneme awareness in either language. The data provide further evidence that phonological awareness is a language-general ability but that cross-language application depends on the similarity between the phonological structures of a child's L1 and L2. Implications for classroom teaching are briefly discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Efficient self-assembly of human papillomavirus type 16 L1 and L1-L2 into virus-like particles.

    Science.gov (United States)

    Kirnbauer, R; Taub, J; Greenstone, H; Roden, R; Dürst, M; Gissmann, L; Lowy, D R; Schiller, J T

    1993-12-01

    The L1 genes of two human papillomavirus type 16 (HPV16) isolates derived from condylomata acuminata were used to express the L1 major capsid protein in insect cells via recombinant baculoviruses. Both L1 major capsid proteins self-assembled into virus-like particles (VLP) with high efficiency and could be purified in preparative amounts on density gradients. The yield of VLP was 3 orders of magnitude higher than what has been obtained previously, using L1 derived from the prototype HPV16. DNA sequence comparison identified a single nonconserved amino acid change to be responsible for the inefficient self-assembly of the prototype L1. VLP were also obtained by expressing L1 of HPV6, HPV11, and cottontail rabbit papillomavirus, indicating that L1 from a variety of papillomaviruses has the intrinsic capacity to self-assemble into VLP. Coexpression of HPV16 L1 plus L2 by using a baculovirus double-expression vector also resulted in efficient self-assembly of VLP, and the average particle yield increased about fourfold in comparison to when L1 only was expressed. Coimmunoprecipitation of L1 and L2 and cosedimentation of the two proteins in a sucrose gradient demonstrated that L2 was incorporated into the particles. The ability to generate preparative amounts of HPV16 L1 and L1-L2 VLP may have implications for the development of a serological assay to detect anti-HPV16 virion immune responses to conformational epitopes and for immunoprophylaxis against HPV16 infection.

  6. Adaptive L1/2 Shooting Regularization Method for Survival Analysis Using Gene Expression Data

    Directory of Open Access Journals (Sweden)

    Xiao-Ying Liu

    2013-01-01

    Full Text Available A new adaptive L1/2 shooting regularization method for variable selection based on the Cox’s proportional hazards mode being proposed. This adaptive L1/2 shooting algorithm can be easily obtained by the optimization of a reweighed iterative series of L1 penalties and a shooting strategy of L1/2 penalty. Simulation results based on high dimensional artificial data show that the adaptive L1/2 shooting regularization method can be more accurate for variable selection than Lasso and adaptive Lasso methods. The results from real gene expression dataset (DLBCL also indicate that the L1/2 regularization method performs competitively.

  7. [Experimental observation of toxic effect of Bacillus thuringiensis var. israelensis against Aedes, Culex and Anopheles larvae].

    Science.gov (United States)

    Li, Ju-Lin; Zhu, Guo-Ding; Zhou, Hua-Yun; Tang, Jian-Xia; Cao, Jun

    2014-02-01

    To evaluate the toxic effect of Bacillus thuringiensis var. israelensis (Bti) wettable powder against Aedes, Culex and Anopheles larvae. The biological assay was applied to test the lethal concentration of 50% (LC50) of Bti wettable powder against Aedes, Culex and Anopheles larvae. The LC50(s) of Bti wettable powder against Aedes albopictus, Culex pipiens pallens and Anopheles sinensis larvae were 0.104, 0.160 microg/ml and 0.324 microg/ml, respectively; its biological potencies against them were 0.125, 0.192 IU/ml and 0.389 IU/ml, respectively. The LC50(s) of continuous contact of Bti wettable powder with An. sinensis stage III larvae for 1, 2 d and 3 d were 0.324, 0.092 microg/ml and 0.032 microg/ml, respectively, and its biological potencies were 0.389, 0.110 IU/ml and 0.038 IU/ml, respectively. The LC50(s) of the bacteria against An. sinensis stage I , II, III, IV were 0.024, 0.137, 0.324 microg/ml and 0.450 microg/ml, respectively, and the biological potencies were 0.029, 0.164, 0.389 IU/ml and 0.540 IU/ml, respectively. Bti wettable powder has a good toxicity to Aedes, Culex and Anopheles larvae, especially for the latter two. It is better to apply the bacteria at the early stage of mosquito larvae.

  8. Predation efficiency of Anopheles gambiae larvae by aquatic predators in western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Nyindo Mramba

    2011-07-01

    Full Text Available Abstract Background The current status of insecticide resistance in mosquitoes and the effects of insecticides on non-target insect species have raised the need for alternative control methods for malaria vectors. Predation has been suggested as one of the important regulation mechanisms for malaria vectors in long-lasting aquatic habitats, but the predation efficiency of the potential predators is largely unknown in the highlands of western Kenya. In the current study, we examined the predation efficiency of five predators on Anopheles gambiae s.s larvae in 24 hour and semi- field evaluations. Methods Predators were collected from natural habitats and starved for 12 hours prior to starting experiments. Preliminary experiments were conducted to ascertain the larval stage most predated by each predator species. When each larval instar was subjected to predation, third instar larvae were predated at the highest rate. Third instar larvae of An. gambiae were introduced into artificial habitats with and without refugia at various larval densities. The numbers of surviving larvae were counted after 24 hours in 24. In semi-field experiments, the larvae were counted daily until they were all either consumed or had developed to the pupal stage. Polymerase chain reaction was used to confirm the presence of An. gambiae DNA in predator guts. Results Experiments found that habitat type (P P P P An. gambiae DNA was found in at least three out of ten midguts for all predator species. Gambusia affins was the most efficient, being three times more efficient than tadpoles. Conclusion These experiments provide insight into the efficiency of specific natural predators against mosquito larvae. These naturally occurring predators may be useful in biocontrol strategies for aquatic stage An. gambiae mosquitoes. Further investigations should be done in complex natural habitats for these predators.

  9. Differential involvement of Atg16L1 in Crohn disease and canonical autophagy: analysis of the organization of the Atg16L1 complex in fibroblasts.

    Science.gov (United States)

    Fujita, Naonobu; Saitoh, Tatsuya; Kageyama, Shun; Akira, Shizuo; Noda, Takeshi; Yoshimori, Tamotsu

    2009-11-20

    A single nucleotide polymorphism in Atg16L1, an autophagy-related gene (ATG), is a risk factor for Crohn disease, a major form of chronic inflammatory bowel disease. However, it is still unknown how the Atg16L1 variant contributes to disease development. The Atg16L1 protein possesses a C-terminal WD repeat domain whose function is entirely unknown, and the Crohn disease-associated mutation (T300A) is within this domain. To elucidate the function of the WD repeat domain, we established an experimental system in which a WD repeat domain mutant of Atg16L1 is stably expressed in Atg16L1-deficient mouse embryonic fibroblasts. Using the system, we show that the Atg16L1 complex forms a dimeric complex and that the total Atg16L1 protein level is strictly maintained, possibly by the ubiquitin proteasome system. Furthermore, we show that an Atg16L1 WD repeat domain deletion and the T300A mutant have little impact on canonical autophagy and autophagy against Salmonella enterica serovar Typhimurium. Therefore, we propose that Atg16L1 T300A is differentially involved in Crohn disease and canonical autophagy.

  10. Efficient self-assembly of human papillomavirus type 16 L1 and L1-L2 into virus-like particles.

    OpenAIRE

    Kirnbauer, R; Taub, J; Greenstone, H; Roden, R; Dürst, M; Gissmann, L; Lowy, D R; Schiller, J T

    1993-01-01

    The L1 genes of two human papillomavirus type 16 (HPV16) isolates derived from condylomata acuminata were used to express the L1 major capsid protein in insect cells via recombinant baculoviruses. Both L1 major capsid proteins self-assembled into virus-like particles (VLP) with high efficiency and could be purified in preparative amounts on density gradients. The yield of VLP was 3 orders of magnitude higher than what has been obtained previously, using L1 derived from the prototype HPV16. DN...

  11. The Macroevolutionary Interplay Between Planktic Larvae and Benthic Predators

    Science.gov (United States)

    Peterson, K. J.

    2004-12-01

    Many marine invertebrates have a complex life cycle whereby the egg, rather than developing directly to the juvenile stage, develops instead into a intermediate larval form which may spend weeks to months feeding in the plankton before it becomes competent to undergo metamorphosis into the benthic juvenile. Because the selective advantages provided to the animal by having a planktotrophic larval stage are largely unknown, the reasons behind their origin and subsequent maintenance over geological time are not well understood. Using both a molecular clock and the fossil record, I show that four primitively non-feeding larval forms evolved sometime between the late Ediacaran and Early Cambrian, and feeding larvae appear to have evolved from non-feeding ancestors sometime between the Late Cambrian and Middle Ordovician in at least five, if not eight, of eight different clades analyzed. Thus, the initial exploitation of the predator-free pelagos by larvae was achieved independently multiple times by the end of the Early Cambrian, most likely driven by benthic predation pressures upon developing eggs and embryos. Then, because the evolution of larval planktotrophy from lecithotrophic ancestors correlates with the dramatic rise in the generic number of benthic suspension feeders in the Early Ordovician, it seems likely that benthic suspension feeding selected for fecundity, and thus indirectly for planktotrophy, in multiple lineages of marine invertebrates by the end of the Middle Ordovician.

  12. Activity of R(+ limonene against Anisakis larvae

    Directory of Open Access Journals (Sweden)

    Filippo Giarratana

    2015-12-01

    Full Text Available The aim of this work is to evaluate the activity of R(+ limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showing a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+ limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status.

  13. Activity of R(+) Limonene Against Anisakis Larvae

    Science.gov (United States)

    Muscolino, Daniele; Panebianco, Felice; Patania, Andrea; Benianti, Chiara; Ziino, Graziella; Giuffrida, Alessandro

    2015-01-01

    The aim of this work is to evaluate the activity of R(+) limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showed a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+) limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status. PMID:27800423

  14. Activity of R(+) limonene against Anisakis larvae

    OpenAIRE

    Filippo Giarratana; Daniele Muscolino; Felice Panebianco; Andrea Patania; Chiara Benianti; Graziella Ziino; Alessandro Giuffrida

    2015-01-01

    The aim of this work is to evaluate the activity of R(+) limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showing a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+) limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status.

  15. Association between PD-L1 expression combined with tumor-infiltrating lymphocytes and the prognosis of patients with advanced hypopharyngeal squamous cell carcinoma.

    Science.gov (United States)

    Ono, Takeharu; Azuma, Koichi; Kawahara, Akihiko; Sasada, Tetsuro; Hattori, Satoshi; Sato, Fumihiko; Shin, Buichiro; Chitose, Shun-Ich; Akiba, Jun; Hirohito, Umeno

    2017-11-03

    Limited information is available regarding the immune-related prognostic factors of patients with advanced hypopharyngeal squamous cell carcinoma (HPSCC). The expression of programmed cell death-ligand 1 (PD-L1) in tumor cells contributes to a mechanism that allows cancer cells to escape immune surveillance. We investigated whether PD-L1 or human leukocyte antigen (HLA) class I expression in tumor cells and the tumor-infiltrating lymphocyte (TIL) density were associated with the tumor response to neoadjuvant chemotherapy (NAC) and survival in patients with advanced HPSCC. We retrospectively reviewed 83 consecutive patients with stage III or IV HPSCC who received NAC. We evaluated PD-L1 and HLA class I expression and TIL density using immunohistochemistry. Univariate and multivariate analyses demonstrated that CD8 + TIL density was an independent and significant predictive factor for the response to NAC, progression-free survival (PFS) and overall survival (OS), whereas PD-L1 or HLA class I expression did not significantly correlate. The subgroup analysis revealed that a higher CD8 + TIL density without detectable PD-L1 expression tended to be associated with longer patient survival. These results suggest that PD-L1 expression levels combined with CD8 + TIL density may serve as a predictive biomarker for patients with stage III or IV HPSCC receiving NAC.

  16. Mananoligossacarídeo em dietas para larvas de tilápia Mannanoligosaccharides in diets for tilapia larvae

    Directory of Open Access Journals (Sweden)

    Kátia Kalko Schwarz

    2011-12-01

    Full Text Available Este experimento foi realizado para avaliar níveis crescentes de mananoligossacarídeo (MOS na dieta de larvas de tilápias-do-nilo (linhagem Supreme® na fase de reversão sexual durante 30 dias. Larvas de tilápia-do-nilo (n=1500, P=0,01 g ± 0,001 g foram distribuídas aleatoriamente em 30 tanques de 100 litros. Os peixes foram distribuídos em delineamento inteiramente casualizado, composto por seis tratamentos e cinco repetições. A dieta controle (isenta de MOS foi elaborada para conter aproximadamente 35% de proteína bruta e 3.100 kcal de ED/kg. As demais foram suplementadas com 0; 0,15; 0,30; 0,45; 0,60 e 0,75% de MOS em substituição ao milho da dieta controle. Com o aumento nos níveis de MOS nas dietas, foi observado aumento linear sobre o comprimento do intestino, a altura das vilosidades intestinais e a densidade dos vilos. Não houve diferença na composição corporal, no ganho em peso, no peso final, no comprimento final, no fator de condição, na taxa de sobrevivência e no número de células caliciformes do intestino das larvas. Os níveis de MOS tiveram efeito quadrático sobre a conversão alimentar, cujos melhores resultados foram obtidos com 0,34% de MOS. A utilização de MOS no nível de 0,34% em dietas para larvas de tilápia-do-nilo melhora a conversão alimentar e promove aumento do comprimento do intestino, da altura das vilosidades e da densidade de vilos intestinal.This experiment was conducted to evaluate increasing levels of mannanoligosaccharides (MOS in the diet of Nile tilapia larvae (Supreme® at the sex reversal stage for 30 days. Nile tilapia larvae (n = 1500, p = 0.01 ± 0.001 g, were randomly distributed in 30 tanks of 100 liters each, for 30 days. The fish were distributed in a randomized design with six treatments and five replicates. The control diet (no MOS was elaborated to contain approximately 35% of crude protein and 3,100 kcal DE/kg. Mannanoligosaccharides were included in the other diets

  17. Fluorescent Beads Are a Versatile Tool for Staging Caenorhabditis elegans in Different Life Histories

    Directory of Open Access Journals (Sweden)

    Liberta Nika

    2016-07-01

    Full Text Available Precise staging of Caenorhabditis elegans is essential for developmental studies in different environmental conditions. In favorable conditions, larvae develop continuously through four larval stages separated by molting periods. Distinguishing molting from intermolt larvae has been achieved using transgenes with molting reporters, therefore requiring strain constructions, or careful observation of individuals for pharyngeal pumping or behavioral quiescence. In unfavorable conditions, larvae can enter the stress-resistant and developmentally arrested dauer larva stage. Identifying dauer larvae has been based on their ability to withstand detergent selection, precluding identification of recovering animals or of mutants with defects in dauer morphogenesis. Here, we describe a simple method to distinguish molting larvae or dauer larvae from intermolt larvae that bypasses the limitations of current methods. Fluorescent latex beads are mixed with the bacterial food source and ingested by intermolt larvae and adults. Molting and dauer larvae do not feed, and therefore lack beads in their digestive tract. The presence of beads can be determined using a dissecting microscope at magnifications as low as 100 ×, or by using a wormsorter for high-throughput experiments. We find that continuously developing bead-lacking larvae display hallmarks of molting, including expression of the mlt-10::gfp molting marker and a lack of pharyngeal pumping. Furthermore, wild-type and mutant dauer larvae produced by any of three common methods are accurately identified by a lack of beads. Importantly, this method is effective in SDS-sensitive mutant backgrounds and can identify recovering dauer larvae, a stage for which there is no other method of positive selection.

  18. Estimation of food limitation of bivalve larvae in coastal waters of north-western Europe

    DEFF Research Database (Denmark)

    Bos, O.G.; Hendriks, I.E.; Strasser, M.

    2006-01-01

    Marine invertebrate recruitment may be affected by food limitation during the pelagic larval life stages. In the present study, field data on abundance of bivalve larvae along with their prey (small phytoplankton) were examined to see whether they were consistent with predictions made...... assimilation rate averaged 7-26% of the maximum assimilation rate. Under the assumptions made for the present study, it is suggested that growth of larvae in north-west European waters is often food-limited. (c) 2005 Elsevier B.V. All rights reserved...

  19. Distribution and abundance of Syacium ovale larvae (Pleuronectiformes: Paralichthyidae in the Gulf of California

    Directory of Open Access Journals (Sweden)

    Gerardo Aceves-Medina

    2003-06-01

    Full Text Available The spawning season of the tonguefish Syacium ovale (Günter 1864 was determined by an analysis of the distribution of preflexion stage larvae in the Gulf of California. The larvae were collected during eight oceanographic surveys between 1984 and 1987. The spawning of this species starts in early summer and ends at the beginning of fall, with the highest reproductive activity in mid summer. The central and southern regions of the Gulf are the most important reproductive area. Spawning is associated with high sea surface temperatures and low plankton biomass, both of which are characteristics of the tropical current that invades the study area during summer.

  20. Garlic essential oil increases rates of eggs fertilization and hatching of Rhamdia quelen larvae in an artificial incubation system

    Directory of Open Access Journals (Sweden)

    Nilton Garcia Marengoni

    Full Text Available ABSTRACT: The objective of this study was to evaluate the effects of garlic (Allium sativum essential oil on the rates of eggs fertilization and hatching and on the normal development of larvae of artificially incubated silver catfish (Rhamdia quelen. The experiment was carried out using a completely randomized experimental design with four treatments and five replicates. The treatments consisted of introducing garlic essential oil into the incubators, which used a closed system of water recirculation, at concentrations of 0, 1, 3, and 5mg L-1. Rates of eggs fertilization and larval hatching were determined at 10 and 24h after the beginning of eggs hydration. Morphology of larvae was assessed with the aid of a stereo microscope to determine the rate of normal development. The concentration of 5mg L-1 promoted better rates of eggs fertilization and larval hatching. Concentrations of garlic essential oil had a linear effect on eggs fertilization rates and larval hatching. Garlic oil did not influence the morphology of the larvae (P>0.05. It is recommended to use 5mg L-1 of garlic essential oil to promote better rates of eggs fertilization and larval hatching of artificially incubated silver catfish.

  1. Determination of methyl methanesulfonate pretreatment effect in Drosophila melanogaster larvaes upon repair mechanisms in somatic cells

    International Nuclear Information System (INIS)

    Hernandez Paz, M.

    1992-01-01

    To make evident the existence of SOS repair mecanism in somatic cells, larvaes of drosophila melanogaster with MWH markers for females and FLR markers for males were used. This larvaes received a pretreatment with MMS at concentrations of 0.0007% and 0.0014% during 24 hours and latter a treatment with gamma rays at different dosis. SMART program was used to make stastistical evaluations. Small spots were observed which can have two origins. First could be damage in the last part of third stage in which cells are in last divisions and second could be the damage to larvaes in early stages in shich pretreatment with MMS cause lesions which prevent the reproduction of the cells. Also big spots were observed which presence is due to recombination. It was detected than the bigger the concentration of MMS and radiation dose, the bigger the induced damage. In some groups such observation was impossible may be to technical problems as relative humidity, out of phase in the growth of larvaes giving place that treatment were given in three stages. For this reasons it was impossible to discriminate if drosophila melanogaster is wheter or not capable to induce a repair mechanism (Author)

  2. Do L2 Writing Courses Affect the Improvement of L1 Writing Skills via Skills Transfer from L2 to L1?

    Science.gov (United States)

    Gonca, Altmisdort

    2016-01-01

    This study investigates the relationship of second language (L2) writing skills proficiency with the first language (L1) writing skills, in light of the language transfer. The study aims to analyze the positive effects of L2 writing proficiency on L1 writing proficiency. Forty native Turkish-speaking university students participated in the study.…

  3. Quantifying the Quality Difference between L1 and L2 Essays: A Rating Procedure with Bilingual Raters and L1 and L2 Benchmark Essays

    Science.gov (United States)

    Tillema, Marion; van den Bergh, Huub; Rijlaarsdam, Gert; Sanders, Ted

    2013-01-01

    It is the consensus that, as a result of the extra constraints placed on working memory, texts written in a second language (L2) are usually of lower quality than texts written in the first language (L1) by the same writer. However, no method is currently available for quantifying the quality difference between L1 and L2 texts. In the present…

  4. L1 Korean and L1 Mandarin L2 English Learners' Acquisition of the Count/Mass Distinction in English

    Science.gov (United States)

    Choi, Sea Hee; Ionin, Tania; Zhu, Yeqiu

    2018-01-01

    This study investigates the second language (L2) acquisition of the English count/mass distinction by speakers of Korean and Mandarin Chinese, with a focus on the semantics of atomicity. It is hypothesized that L1-Korean and L1-Mandarin L2-English learners are influenced by atomicity in the use of the count/mass morphosyntax in English. This…

  5. Nuclear phosphoproteome analysis of 3T3-L1 preadipocyte differentiation reveals system-wide phosphorylation of transcriptional regulators

    DEFF Research Database (Denmark)

    Rabiee, Atefeh; Schwämmle, Veit; Sidoli, Simone

    2017-01-01

    of which were assigned as regulators of gene expression. Among 288 identified transcriptional regulators, 49 were regulated within four hours of adipogenic stimulation including several known and many novel potential adipogenic regulators. A kinase-substrate database for 3T3-L1 preadipocytes established...... stages (4 hours) of preadipocyte differentiation. We identified a total of 4072 proteins including 2434 phosphorylated proteins, a majority of which were assigned as regulators of gene expression. Our results demonstrate that adipogenic stimuli increase the nuclear abundance and/or the phosphorylation...... for 3T3-L1 preadipocytes by investigating the relationship between protein kinases and protein phosphorylation sites identified in our dataset. A majority of the putative protein kinases belong to the cyclin-dependent kinase (CDK) family and the mitogen activated protein kinase (MAPK) family including P...

  6. Metacognitive Online Reading Strategy Use: Readers' Perceptions in L1 and L2

    Science.gov (United States)

    Taki, Saeed

    2016-01-01

    This study aimed to explore whether first-language (L1) readers of different language backgrounds would employ similar metacognitive online reading strategies and whether reading online in a second language (L2) could be influenced by L1 reading strategies. To this end, 52 Canadian college students as English L1 readers and 38 Iranian university…

  7. Extensive transduction of nonrepetitive DNA mediated by L1 retrotransposition in cancer genomes

    NARCIS (Netherlands)

    Tubio, Jose M. C.; Li, Yilong; Ju, Young Seok; Martincorena, Inigo; Cooke, Susanna L.; Tojo, Marta; Gundem, Gunes; Pipinikas, Christodoulos P.; Zamora, Jorge; Raine, Keiran; Menzies, Andrew; Roman-Garcia, Pablo; Fullam, Anthony; Gerstung, Moritz; Shlien, Adam; Tarpey, Patrick S.; Papaemmanuil, Elli; Knappskog, Stian; van Loo, Peter; Ramakrishna, Manasa; Davies, Helen R.; Marshall, John; Wedge, David C.; Teague, Jon W.; Butler, Adam P.; Nik-Zainal, Serena; Alexandrov, Ludmil; Behjati, Sam; Yates, Lucy R.; Bolli, Niccolo; Mudie, Laura; Hardy, Claire; Martin, Sancha; McLaren, Stuart; O'Meara, Sarah; Anderson, Elizabeth; Maddison, Mark; Gamble, Stephen; Foster, Christopher; Warren, Anne Y.; Whitaker, Hayley; Brewer, Daniel; Eeles, Rosalind; Cooper, Colin; Neal, David; Lynch, Andy G.; Visakorpi, Tapio; Isaacs, William B.; van't Veer, Laura; Caldas, Carlos; Desmedt, Christine; Sotiriou, Christos; Aparicio, Sam; Foekens, John A.; Eyfjörd, Jórunn Erla; Lakhani, Sunil R.; Thomas, Gilles; Myklebost, Ola; Span, Paul N.; Børresen-Dale, Anne-Lise; Richardson, Andrea L.; van de Vijver, Marc; Vincent-Salomon, Anne; van den Eynden, Gert G.; Flanagan, Adrienne M.; Futreal, P. Andrew; Janes, Sam M.; Bova, G. Steven; Stratton, Michael R.; McDermott, Ultan; Campbell, Peter J.; Provenzano, Elena; Purdie, Colin; Pinder, Sarah; MacGrogan, Gaetan; Larsimont, Denis; Grabau, Dorthe; Sauer, Torill; Garred, Øystein; Ehinger, Anna; van Deurzen, C. H. M.; Salgado, Roberto; Brock, Jane E.; Giri, Dilip D.; Arnould, Laurent; Jacquemier, Jocelyne; Treilleux, Isabelle; Chin, Suet-Feung; Fatima, Aquila; Thompson, Alastair M.; Stenhouse, Alasdair; Foekens, John; Martens, John; Sieuwerts, Anieta; Brinkman, Arjen; Stunnenberg, Henk; Sweep, Fred; Broeks, Annegein; Langerod, Anita; Aparicio, Samuel; Simpson, Peter; van 't Veer, Laura; Hilmarsdottir, Holmfridur; Jonasson, Jon G.; Lee, Ming Ta Michael; Wong, Bernice Huimin; Tan, Benita Kiat Tee; Hooijer, Gerrit K. J.; Wedge, David; Kremeyer, Barbara; Butler, Adam; Lynch, Andrew; Edwards, Sandra; Camacho, Niedzica; Massie, Charlie; Kote-Jarai, Zsofia; Dennis, Nening; Merson, Sue; Kay, Jonathan; Corbishley, Cathy; Thomas, Sarah; Nik-Zainai, Serena; Matthews, Lucy; Clark, Jeremy; Hurst, Rachel; Mithen, Richard; Cooke, Susanna; Jones, David; Stebbings, Lucy; Hinton, Jon; Teague, Jon; Joseph, Olivia; Goody, Victoria; Robinson, Ben; Greenman, Christopher; Berney, Dan; Hazell, Steven; Livni, Naomi; Fisher, Cyril; Ogden, Christopher; Kumar, Pardeep; Thompson, Alan; Woodhouse, Christopher; Nicol, David; Mayer, Erik; Dudderidge, Tim; Shah, Nimish; Gnanapragasam, Vincent; Campbell, Peter; Futreal, Andrew; Easton, Douglas; Stratton, Michael

    2014-01-01

    Long interspersed nuclear element-1 (L1) retrotransposons are mobile repetitive elements that are abundant in the human genome. L1 elements propagate through RNA intermediates. In the germ line, neighboring, nonrepetitive sequences are occasionally mobilized by the L1 machinery, a process called 3'

  8. The Influence of Schema and Cultural Difference on L1 and L2 Reading

    Science.gov (United States)

    Yang, Shi-sheng

    2010-01-01

    Reading in L1 shares numerous basic elements with reading in L2, and the processes also differ greatly. Intriguing questions involve whether there are two parallel cognitive processes at work, or whether there are processing strategies that accommodate both L1 and L2. This paper examines how reading in L1 is different from and similar to reading…

  9. L1 Glosses: Effects on EFL Learners' Reading Comprehension and Vocabulary Retention

    Science.gov (United States)

    Cheng, Ying-Hsueh; Good, Robert L.

    2009-01-01

    The present study examines the effects of 3 kinds of glosses--first-language (L1) Chinese glosses plus second-language (L2) English example sentences, L1 in-text glosses, and L1 marginal glosses--in comparison with a no-gloss condition in reading an English passage, to explore whether providing glosses can facilitate reading comprehension and…

  10. Survival, growth and reproduction of cryopreserved larvae from a marine invertebrate, the Pacific oyster (Crassostrea gigas.

    Directory of Open Access Journals (Sweden)

    Marc Suquet

    Full Text Available This study is the first demonstration of successful post-thawing development to reproduction stage of diploid cryopreserved larvae in an aquatic invertebrate. Survival, growth and reproductive performances were studied in juvenile and adult Pacific oysters grown from cryopreserved embryos. Cryopreservation was performed at three early stages: trochophore (13±2 hours post fertilization: hpf, early D-larvae (24±2 hpf and late D-larvae (43±2 hpf. From the beginning (88 days at the end of the ongrowing phase (195 days, no mortality was recorded and mean body weights did not differ between the thawed oysters and the control. At the end of the growing-out phase (982 days, survival of the oysters cryopreserved at 13±2 hpf and at 43±2 hpf was significantly higher (P<0.001 than those of the control (non cryopreserved larvae. Only the batches cryopreserved at 24±2 hpf showed lower survival than the control. Reproductive integrity of the mature oysters, formely cryopreserved at 13±2 hpf and 24±2 hpf, was estimated by the sperm movement and the larval development of their offspring in 13 crosses gamete pools (five males and five females in each pool. In all but two crosses out of 13 tested (P<0.001, development rates of the offspring were not significantly different between frozen and unfrozen parents. In all, the growth and reproductive performances of oysters formerly cryopreserved at larval stages are close to those of controls. Furthermore, these performances did not differ between the three initial larval stages of cryopreservation. The utility of larvae cryopreservation is discussed and compared with the cryopreservation of gametes as a technique for selection programs and shellfish cryobanking.

  11. Responses of bay anchovy (Anchoa mitchilli) larvae under lethal and sublethal scenarios of crude oil exposure.

    Science.gov (United States)

    Duffy, Tara A; Childress, William; Portier, Ralph; Chesney, Edward J

    2016-12-01

    Bay anchovy (Anchoa mitchilli) is an ecologically important zooplanktivorous fish inhabiting estuaries of the Gulf of Mexico and eastern North America from Maine to Florida. Because they have a protracted spawning season (spring through fall) and are abundant at all life stages in coastal estuaries, their eggs and larvae likely encountered oil that reached the coast during the Deepwater Horizon oil spill. We compared responses to oil exposure at different life stages and at lethal and sublethal conditions using acute, 24h exposures. In a series of experiments, bay anchovy larvae were exposed to high energy water accommodated fractions (HEWAF) and chemically-enhanced WAF (CEWAF) at two stages of larval development (5 and 21 days post hatch, dph). HEWAF oil exposures induced significantly greater life stage dependent sensitivity at 5 dph than at 21 dph but chemically dispersed (CEWAF) exposure mortality was more variable and LC 50s were not significantly different between 5 and 21dph larvae. Acute exposure to two low-level concentrations of CEWAF did not result in significant mortality over 24h, but resulted in a 25-77% reduction in larval survival and a 12-34% reduction in weight specific growth after six days of post-exposure growth following the initial 24h exposure. These results show that younger (5 dph) bay anchovy larvae are more vulnerable to acute oil exposure than older (21 dph) larvae, and that acute responses do not accurately reflect potential population level mortality and impacts to growth and development. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Tracheopulmonary myiasis caused by a mature third-instar Cuterebra larva: case report and review.

    Science.gov (United States)

    Cornet, Muriel; Florent, Martine; Lefebvre, Aurélie; Wertheimer, Christophe; Perez-Eid, Claudine; Bangs, Michael J; Bouvet, Anne

    2003-12-01

    Myiasis is the infestation of vertebrate tissues with fly larvae (Diptera). Most human cases in North America are subcutaneous forms due to Dermatobia hominis imported from Central and South America. Human cases of myiasis acquired in North America are rare and are primarily subdermal or ophthalmologic forms of infestation caused by early stages of Cuterebra larvae. We report an unusual case of tracheopulmonary myiasis, resulting from the in situ development of a mature cuterebrine larva associated with high eosinophilia. Only two other cases of tracheopulmonary cuterebrid myiasis have been reported in humans, and they are reviewed herein. Cuterebra myiasis (cuterebrosis) remains a rare and aberrant cause of tracheopulmonary disease and is a newly described cause of eosinophilia in humans.

  13. [Light and electron microscopic studies of oropharyngeal epithelium in Salamandra salamandra (L.) (Urodela: Salamandridae) larvae].

    Science.gov (United States)

    Clemen, G

    1984-01-01

    The oropharyngeal-epithelium of intrauterine and free swimming larvae of Salamandra salamandra has been investigated by electron microscopy. With the exception of the toothed areas, where it is multi-layered, the epithelium of intrauterine larvae consists of two cell layers, pavement and basal cells. In older larvae, however, the entire epithelium is multi-layered. The outermost layer contains nonciliated pavement cells, goblet cells and sporadically mitochondria-rich cells. Both, goblet cells and pavement cells synthesize mainly acid mucosubstances, which are localized in big confluent secretory granules in the former and in small granules immediately beneath the apical plasmalemm in the latter. In the second layer different developmental stages of goblet cells and pavement cells can be identified.

  14. Tracheopulmonary Myiasis Caused by a Mature Third-Instar Cuterebra Larva: Case Report and Review

    Science.gov (United States)

    Cornet, Muriel; Florent, Martine; Lefebvre, Aurélie; Wertheimer, Christophe; Perez-Eid, Claudine; Bangs, Michael J.; Bouvet, Anne

    2003-01-01

    Myiasis is the infestation of vertebrate tissues with fly larvae (Diptera). Most human cases in North America are subcutaneous forms due to Dermatobia hominis imported from Central and South America. Human cases of myiasis acquired in North America are rare and are primarily subdermal or ophthalmologic forms of infestation caused by early stages of Cuterebra larvae. We report an unusual case of tracheopulmonary myiasis, resulting from the in situ development of a mature cuterebrine larva associated with high eosinophilia. Only two other cases of tracheopulmonary cuterebrid myiasis have been reported in humans, and they are reviewed herein. Cuterebra myiasis (cuterebrosis) remains a rare and aberrant cause of tracheopulmonary disease and is a newly described cause of eosinophilia in humans. PMID:14662989

  15. Prolonged pre-incubation increases the susceptibility of Galleria mellonella larvae to bacterial and fungal infection.

    Science.gov (United States)

    Browne, Niall; Surlis, Carla; Maher, Amie; Gallagher, Clair; Carolan, James C; Clynes, Martin; Kavanagh, Kevin

    2015-01-01

    Galleria mellonella larvae are widely used for assessing the virulence of microbial pathogens and for measuring the in vivo activity of antimicrobial agents and produce results comparable to those that can be obtained using mammals. The aim of the work described here was to ascertain the effect of pre-incubation at 15°C for 1, 3, 6 or 10 weeks on the susceptibility of larvae to infection with Candida albicans and Staphylococcus aureus. Larvae infected with C. albicans after 1 week pre-incubation at 15°C showed 73.3 ± 3.3% survival at 24 hours post-infection while those infected after 10 weeks pre-incubation showed 30 ± 3.3% survival (P system but the duration of the pre-incubation stage significantly affects their susceptibility to microbial pathogens possibly as a result of altered metabolism.

  16. The innate immune and systemic response in honey bees to a bacterial pathogen, Paenibacillus larvae

    Directory of Open Access Journals (Sweden)

    Foster Leonard J

    2009-08-01

    Full Text Available Abstract Background There is a major paradox in our understanding of honey bee immunity: the high population density in a bee colony implies a high rate of disease transmission among individuals, yet bees are predicted to express only two-thirds as many immunity genes as solitary insects, e.g., mosquito or fruit fly. This suggests that the immune response in bees is subdued in favor of social immunity, yet some specific immune factors are up-regulated in response to infection. To explore the response to infection more broadly, we employ mass spectrometry-based proteomics in a quantitative analysis of honey bee larvae infected with the bacterium Paenibacillus larvae. Newly-eclosed bee larvae, in the second stage of their life cycle, are susceptible to this infection, but become progressively more resistant with age. We used this host-pathogen system to probe not only the role of the immune system in responding to a highly evolved infection, but also what other mechanisms might be employed in response to infection. Results Using quantitative proteomics, we compared the hemolymph (insect blood of five-day old healthy and infected honey bee larvae and found a strong up-regulation of some metabolic enzymes and chaperones, while royal jelly (food and energy storage proteins were down-regulated. We also observed increased levels of the immune factors prophenoloxidase (proPO, lysozyme and the antimicrobial peptide hymenoptaecin. Furthermore, mass spectrometry evidence suggests that healthy larvae have significant levels of catalytically inactive proPO in the hemolymph that is proteolytically activated upon infection. Phenoloxidase (PO enzyme activity was undetectable in one or two-day-old larvae and increased dramatically thereafter, paralleling very closely the age-related ability of larvae to resist infection. Conclusion We propose a model for the host response to infection where energy stores and metabolic enzymes are regulated in concert with direct

  17. Energy density of zooplankton and fish larvae in the southern Catalan Sea (NW Mediterranean)

    Science.gov (United States)

    Barroeta, Ziortza; Olivar, M. Pilar; Palomera, Isabel

    2017-06-01

    In marine communities, energy of small planktonic organisms is transferred to their predators through feeding. The energy accumulated as organic substances by the different plankton organisms (Energetic Density content, ED) has been analysed in high latitudes and tropical areas, but not in the Mediterranean Sea. In this study, we approach this type of investigation for Mediterranean plankton through measures of total calorimetric content using an oxygen bomb calorimeter. We examined the spatiotemporal variation in the ED of microplankton (50-200 μm) and mesozooplankton (200-2000 μm), and two plankton-consumers, sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) larvae. The study was carried out during the winter and summer of 2013 off the Ebro River Delta (NW Mediterranean Sea). Both plankton fractions showed a more coastal distribution and higher biomasses during winter, the period of sardine larvae occurrences, in front of a wider cross-shelf distribution and lower biomasses in summer, when anchovy appeared. ED values increased with the size of each plankton component, i.e., microzooplankton < mesozooplankton < fish larvae. A tendency for higher plankton ED in the winter period was observed, although being only significant for coastal zone, associated to the more productive waters there. Sardine and anchovy larvae showed an increasing trend in the amount of energy during development, with significantly lower ED between early larvae (6-10 mm standard length) and late postflexion stages (16-20 mm standard length). Small larvae of both species departed from a similarly low ED content, but in the next two size classes sardine larvae showed higher ED values than anchovy, being significantly higher in the 16-20 mm size class. Information on larval feeding patterns and larval growth rates for each species were used to discuss differences in energy allocation strategies.

  18. Proteomic and metabolomic analysis reveals rapid and extensive nicotine detoxification ability in honey bee larvae.

    Science.gov (United States)

    du Rand, Esther E; Human, Hannelie; Smit, Salome; Beukes, Mervyn; Apostolides, Zeno; Nicolson, Susan W; Pirk, Christian W W

    2017-03-01

    Despite potential links between pesticides and bee declines, toxicology information on honey bee larvae (Apis mellifera) is scarce and detoxification mechanisms in this development stage are virtually unknown. Larvae are exposed to natural and synthetic toxins present in pollen and nectar through consumption of brood food. Due to the characteristic intensive brood care displayed by honey bees, which includes progressive feeding throughout larval development, it is generally assumed that larvae rely on adults to detoxify for them and exhibit a diminished detoxification ability. We found the opposite. We examined the proteomic and metabolomic responses of in vitro reared larvae fed nicotine (an alkaloid found in nectar and pollen) to understand how larvae cope on a metabolic level with dietary toxins. Larvae were able to effectively detoxify nicotine through an inducible detoxification mechanism. A coordinated stress response complemented the detoxification processes, and we detected significant enrichment of proteins functioning in energy and carbohydrate metabolism, as well as in development pathways, suggesting that nicotine may promote larval growth. Further exploration of the metabolic fate of nicotine using targeted mass spectrometry analysis demonstrated that, as in adult bees, formation of 4-hydroxy-4-(3-pyridyl) butanoic acid, the result of 2'C-oxidation of nicotine, is quantitatively the most significant pathway of nicotine metabolism. We provide conclusive evidence that larvae are capable of effectively catabolising a dietary toxin, suggesting that increased larval sensitivity to specific toxins is not due to diminished detoxification abilities. These findings broaden the current understanding of detoxification biochemistry at different organizational levels in the colony, bringing us closer to understanding the capacity of the colony as a superorganism to tolerate and resist toxic compounds, including pesticides, in the environment. Copyright © 2017

  19. Toxicity of cypermethrin and deltamethrin insecticides on embryos and larvae of Physalaemus gracilis (Anura: Leptodactylidae).

    Science.gov (United States)

    Macagnan, Natani; Rutkoski, Camila F; Kolcenti, Cassiane; Vanzetto, Guilherme V; Macagnan, Luan P; Sturza, Paola F; Hartmann, Paulo A; Hartmann, Marilia T

    2017-09-01

    It is important to establish the toxicity pesticides against non-target species, especially those pesticides used in commercial formulations. Pyrethroid insecticides are widely used in agriculture despite their toxicity to aquatic animals. In this study, we determine the toxicity of commercial formulation of two pyrethroid insecticides, cypermethrin and deltamethrin, in two life stages of Physalaemus gracilis, a frog that breeds in agricultural ecosystems and has potential contact with pyrethroid pesticides. The acute toxicity test (96 h) was carried out with embryos of stage 17:18 and larvae of stages 24:25. Embryos were more resistant to both pesticides than larvae. In embryo mobility assays, we found that both pesticides caused spasmodic contractions, suggestive of neurological effects. In acute toxicity assays, we found that P. gracilis is more resistant to these insecticides than other studied species.

  20. Expression of immune-related genes in embryos and larvae of sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Yang, Aifu; Zhou, Zunchun; Dong, Ying; Jiang, Bei; Wang, Xiaoyu; Chen, Zhong; Guan, Xiaoyan; Wang, Bai; Sun, Dapeng

    2010-11-01

    The echinoderm immunity system has been extensively investigated in adults in several classes such as echinoid and holothuroidea. However, the defense mechanism in embryos and larvae remains largely unexplored. To profile the immune-related genes expression in embryos and larvae and to monitor the stimulation of the innate immune response by lipopolysaccharides (LPS) challenge, we investigated the expression patterns of nine immune-related genes in embryos and larvae of sea cucumber (Apostichopus japonicus) at eleven developmental stages using quantitative real-time PCR (qRT-PCR). The expression of six encoding proteins including heat shock protein70 (Hsp70), Hsp90, Hsp gp96, thymosin-beta, ferritin and DD104 protein was detected at all eleven development stages according to mRNA expression data. However, the expression of mannan-binding C-type lectin (MBCL) was detected at early auricularia to juvenile stages, while lysozyme and serine proteinase inhibitor (SPI) were detected only at juvenile stage. Out of these nine genes, three (MBCL, lysozyme and SPI) were found to be up-regulated in mRNA expression upon LPS challenge, whereas the other six showed no significant change. Our study presents a first preliminary view into the expression patterns of immune-related genes at different developmental stages of sea cucumber, which increases the available information on echinoderm immunity. Copyright 2010 Elsevier Ltd. All rights reserved.

  1. siRNA transfection in larvae of the barnacle Amphibalanus amphitrite

    KAUST Repository

    Zhang, G.

    2015-06-25

    RNA interference (RNAi) provides an efficient and specific technique for functional genomic studies. Yet, no successful application of RNAi has been reported in barnacles. In this study, siRNA against p38 MAPK was synthesized and then transfected into A. amphitrite larvae at either the nauplius or cyprid stage, or at both stages. Effects of siRNA transfection on the p38 MAPK level were hardly detectable in the cyprids when they were transfected at the nauplius stage. In contrast, larvae that were transfected at the cyprid stage showed lower levels of p38 MAPK than the blank and reagent controls. However, significantly decreased levels of phosphorylated p38 MAPK (pp38 MAPK) and reduced settlement rates were observed only in ‘double transfections’, in which larvae were exposed to siRNA solution at both the nauplius and cyprid stages. A relatively longer transfection time and more larval cells directly exposed to siRNA might explain the higher efficiency of double transfection experiments.

  2. Vestigial ophiopluteal structures in the lecithotrophic larvae of Ophionereis schayeri (Ophiuroidea).

    Science.gov (United States)

    Selvakumaraswamy, P; Byrne, M

    2000-06-01

    Evolution of echinoderm development from a feeding to a non-feeding mode can be examined by studying non-feeding larvae with structures that appear to be vestiges derived from a feeding ancestral state. The lecithotrophic larvae of the Australian brittle star Ophionereis schayeri possess such features, and the early development of this species was documented by light and scanning electron microscopy. The embryos undergo irregular cleavage, resulting in the formation of different sized blastomeres, with subsequent development through a wrinkled blastula stage. The lecithotrophic larva of O. schayeri possesses several vestigial ophiopluteal structures, including a continuous ciliated band, a larval gut, and a larval skeleton. The ciliated band is a reduced expression of the continuous ciliated band typical of ophioplutei. The larval gut is a transiently complete system, but an esophageal plug and rapid closure of the blastopore renders it nonfunctional. The larval skeleton, though reduced, consists of four rods corresponding to the body, posterolateral, anterolateral, and postoral rods characteristic of an ophiopluteus. Due to a heterochrony in larval skeletogenesis, the postoral rods develop early and simultaneously with the other rods. Compared with the larvae of other lecithotrophic ophiuroids, the larva of O. schayeri is one of the most reduced ophiopluteal forms reported to date.

  3. A magnetic compass that might help coral reef fish larvae return to their natal reef.

    Science.gov (United States)

    Bottesch, Michael; Gerlach, Gabriele; Halbach, Maurits; Bally, Andreas; Kingsford, Michael J; Mouritsen, Henrik

    2016-12-19

    Many coral reef fish larvae spend days to months in the open ocean before settlement on coral reefs [1]. Early in development, larvae have limited swimming capabilities and will therefore be greatly affected by currents. This can potentially result in dispersal distances of tens of kilometers [2]. Nevertheless, up to 60 % of surviving larvae have been shown to return to their natal reefs [2]. To home, the larvae must develop strong swimming capabilities and appropriate orientation mechanisms. Most late-stage larval reef fish can, after being passively drifted for days to weeks, swim strongly [3], and Ostorhinchus doederleini larvae have been shown to use chemotaxis to identify their natal reef once in its vicinity [2] and a sun compass for longer distance orientation [4] during the day. But how do they orient at night? Here, we show that newly settled fish caught at One Tree Island (OTI) at the Capricorn Bunker Reef Group (Great Barrier Reef) can use geomagnetic compass information to keep a south-east heading. This behavior might help them return to their natal reef in the absence of any celestial cues at night. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Distribution and abundance of fish larvae in the northern Ionian Sea (Eastern Mediterranean)

    Science.gov (United States)

    Granata, Antonia; Cubeta, Annaluce; Minutoli, Roberta; Bergamasco, Alessandro; Guglielmo, Letterio

    2011-09-01

    The purpose of this paper was to study the spatial distribution, abundance and composition of fish larvae in the northern Ionian Sea. Samples were collected to the 600 m depth with an electronic multinet BIONESS during the "INTERREG Italia-Grecia" oceanographic cruise carried out in March 2000 off the Apulian Italian coast. A total of 46 species of teleost early stages were collected, belonging to 38 genera and 22 families. Over 52% of the larvae identified were mesopelagic species, almost 27% were demersal and about 21% pelagic. A total of 307 myctophids, 69 clupeids and 61 gadid post-larvae dominated the community. Benthosema glaciale (mean 6.1 mm SL) was the most abundant species (21.6%), the most frequent in the samples (28.8%), and dominant in the whole study area (mean 1.4 ind/100 m3). Particular attention was given to the horizontal and vertical distribution and abundance of the three dominant post-larval species: Benthosema glaciale, Sprattus sprattus sprattus and Notoscopelus elongatus. The Pearson coefficient ( R = 0.734) showed a high correlation between total zooplankton and fish larval assemblages in terms of spatial distribution abundance values. Regarding the vertical distribution of fish larvae, Sorensen's index ( S = 0.69) showed that fish larvae and total zooplankton abundance peaks co-occurred along the water column.

  5. Stereoselectivity in bioaccumulation and excretion of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae.

    Science.gov (United States)

    Lv, Xiaotian; Liu, Chen; Li, Yaobin; Gao, Yongxin; Wang, Huili; Li, Jianzhong; Guo, Baoyuan

    2014-09-01

    Stereoselectivity in bioaccumulation and excretion of stereoisomers of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae through dietary exposure was investigated. Liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method that use a ChiralcelOD-3R[cellulosetris-Tris-(3, 5-dichlorophenyl-carbamate)] chromatography column was applied to carry out chiral separation of the stereoisomers. Wheat bran was spiked with racemic epoxiconazole at two dose levels of 20mg/kg and 2mg/kg (dry weight) to feed T. molitor larvae. The results showed that both the doses of epoxiconazole were taken up by Tenebrio molitor larvae rapidly at the initial stages. There was a significant trend of stereoselective bioaccumulation in the larvae with a preferential accumulation of (-)-epoxiconazole in the 20mg/kg dose. The stereoselectivity in bioaccumulation in the 2mg/kg dosage was not obvious compared to the 20mg/kg group. Results of excretion indicated an active excretion is an important pathway for the larvae to eliminate epoxiconazole which was a passive transport process with non stereoselectivity. The faster elimination might be the reason for the low accumulation of epoxiconazole, as measured by bioaccumulation factor (BAF). Copyright © 2014 Elsevier Inc. All rights reserved.

  6. INHIBITION OF FATTY ACID DESATURASES IN Drosophila melanogaster LARVAE BLOCKS FEEDING AND DEVELOPMENTAL PROGRESSION.

    Science.gov (United States)

    Wang, Yiwen; da Cruz, Tina Correia; Pulfemuller, Alicia; Grégoire, Stéphane; Ferveur, Jean-François; Moussian, Bernard

    2016-05-01

    Fatty acid desaturases are metabolic setscrews. To study their systemic impact on growth in Drosophila melanogaster, we inhibited fatty acid desaturases using the inhibitor CAY10566. As expected, the amount of desaturated lipids is reduced in larvae fed with CAY10566. These animals cease feeding soon after hatching, and their growth is strongly attenuated. A starvation program is not launched, but the expression of distinct metabolic genes is activated, possibly to mobilize storage material. Without attaining the normal size, inhibitor-fed larvae molt to the next stage indicating that the steroid hormone ecdysone triggers molting correctly. Nevertheless, after molting, expression of ecdysone-dependent regulators is not induced. While control larvae molt a second time, these larvae fail to do so and die after few days of straying. These effects are similar to those observed in experiments using larvae deficient for the fatty acid desaturase1 gene. Based on these data, we propose that the ratio of saturated to unsaturated fatty acids adjusts a sensor system that directs feeding behavior. We also hypothesize that loss of fatty acid desaturase activity leads to a block of the genetic program of development progression indirectly by switching on a metabolic compensation program. © 2016 Wiley Periodicals, Inc.

  7. L^1 stability of conservation laws for a traffic flow model

    Directory of Open Access Journals (Sweden)

    Tong Li

    2001-02-01

    Full Text Available We establish the $L^1$ well-posedness theory for a system of nonlinear hyperbolic conservation laws with relaxation arising in traffic flows. In particular, we obtain the continuous dependence of the solution on its initial data in $L^1$ topology. We construct a functional for two solutions which is equivalent to the $L^1$ distance between the solutions. We prove that the functional decreases in time which yields the $L^1$ well-posedness of the Cauchy problem. We thus obtain the $L^1$-convergence to and the uniqueness of the zero relaxation limit.

  8. N-terminal truncated UCH-L1 prevents Parkinson's disease associated damage.

    Directory of Open Access Journals (Sweden)

    Hee-Jung Kim

    Full Text Available Ubiquitin C-terminal hydrolase-L1 (UCH-L1 has been proposed as one of the Parkinson's disease (PD related genes, but the possible molecular connection between UCH-L1 and PD is not well understood. In this study, we discovered an N-terminal 11 amino acid truncated variant UCH-L1 that we called NT-UCH-L1, in mouse brain tissue as well as in NCI-H157 lung cancer and SH-SY5Y neuroblastoma cell lines. In vivo experiments and hydrogen-deuterium exchange (HDX with tandem mass spectrometry (MS studies showed that NT-UCH-L1 is readily aggregated and degraded, and has more flexible structure than UCH-L1. Post-translational modifications including monoubiquitination and disulfide crosslinking regulate the stability and cellular localization of NT-UCH-L1, as confirmed by mutational and proteomic studies. Stable expression of NT-UCH-L1 decreases cellular ROS levels and protects cells from H2O2, rotenone and CCCP-induced cell death. NT-UCH-L1-expressing transgenic mice are less susceptible to degeneration of nigrostriatal dopaminergic neurons seen in the MPTP mouse model of PD, in comparison to control animals. These results suggest that NT-UCH-L1 may have the potential to prevent neural damage in diseases like PD.

  9. Absence of PD-L1 on tumor cells is associated with reduced MHC I expression and PD-L1 expression increases in recurrent serous ovarian cancer.

    Science.gov (United States)

    Aust, Stefanie; Felix, Sophie; Auer, Katharina; Bachmayr-Heyda, Anna; Kenner, Lukas; Dekan, Sabine; Meier, Samuel M; Gerner, Christopher; Grimm, Christoph; Pils, Dietmar

    2017-03-07

    Immune-evasion and immune checkpoints are promising new therapeutic targets for several cancer entities. In ovarian cancer, the clinical role of programmed cell death receptor ligand 1 (PD-L1) expression as mechanism to escape immune recognition has not been clarified yet. We analyzed PD-L1 expression of primary ovarian and peritoneal tumor tissues together with several other parameters (whole transcriptomes of isolated tumor cells, local and systemic immune cells, systemic cytokines and metabolites) and compared PD-L1 expression between primary tumor and tumor recurrences. All expressed major histocompatibility complex (MHC) I genes were negatively correlated to PD-L1 abundances on tumor tissues, indicating two mutually exclusive immune-evasion mechanisms in ovarian cancer: either down-regulation of T-cell mediated immunity by PD-L1 expression or silencing of self-antigen presentation by down-regulation of the MHC I complex. In our cohort and in most of published evidences in ovarian cancer, low PD-L1 expression is associated with unfavorable outcome. Differences in immune cell populations, cytokines, and metabolites strengthen this picture and suggest the existence of concurrent pathways for progression of this disease. Furthermore, recurrences showed significantly increased PD-L1 expression compared to the primary tumors, supporting trials of checkpoint inhibition in the recurrent setting.

  10. Musculoskeletal anatomy and feeding performance of pre-feeding engyodontic larvae of the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Bouilliart, M.; Tomkiewicz, Jonna; Lauesen, P.

    2015-01-01

    Being part of the elopomorph group of fishes, Anguillidae species show a leptocephalus larval stage. However, due to largely unknown spawning locations and habitats of their earliest life stages, as well as their transparency, these Anguilla larvae are rarely encountered in nature. Therefore......, information regarding the early life history of these larvae, including their exogenous feeding strategy and feeding performance, is rather scarce. To better understand the structural basis and functional performance of larval feeding in captivity, the functional morphology of the cranial musculoskeletal...... system in pre- and first-feeding engyodontic leptocephali of the European eel (Anguilla anguilla) was studied. A 3D reconstruction of the feeding apparatus (head of the leptocephali

  11. l=1 helical axis heliotron device in Kyoto university

    International Nuclear Information System (INIS)

    Nagasaki, K.; Sano, F.; Mizuuchi, T.; Hanatani, K.; Okada, H.; Obiki, T.

    1999-01-01

    Helical systems are an attractive candidate for magnetic fusion reactor. Recently, there has been great progress in theoretical research of three dimensional magnetic field structures, resulting in several kinds of confinement optimization being proposed for toroidal magnetic confinement system. For example, some sophisticated ideas have appeared on stage such as quasi-helical symmetry and quasi-isodynamic system. To find experimentally which way is the best Optimisation, a new helical axis heliotron device, so called 'Heliotron J', is under construction in the Institute of Advanced Energy, Kyoto University, Japan. In this conference, the basic concept and the present status will be presented. In the conventional plane axis helical system, it was difficult to have both good particle confinement and good MHD stability simultaneously. The goal of Heliotron J project is to clarify their compatibility in the spatial axis toroidal device. The best way for Optimising the helical magnetic field configuration will be explored by investigating the plasma response to the change in the field components. The main subjects for plasma experiment are: demonstration of the existence of good magnetic flux surfaces, reduction of neoclassical transport in collisionless regime, MHD Stabilisation in high β plasma, controllability of bootstrap current, good confinement of high energy particles

  12. Citrus Seed Oils Efficacy against Larvae of Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Hazrat Bilal

    2017-10-01

    Full Text Available Background: Dengue fever is a serious public health issue in Pakistan for many years. Globally plants have been reported to contain compounds with insecticidal properties. These properties have been demonstrated more recently on the larval stages of mosquitoes. Therefore, Citrus cultivar seeds were evaluated for larvicidal potential against the primary dengue vector Aedes aegypti.Methods: Extraction of oil was done by a steam distillation method and oils were evaluated according to WHO guidelines for larvicides 2005 for evaluation of insecticidal properties of citrus seed extracts against mosquito larvae.Result: Among the Citrus cultivar seed oil, rough lemon (Citrus jambhiri had the lowest LC50 value (200.79ppm, while musambi (C. sinensis var musambi had the highest LC50 value (457.30ppm after 24 h of exposure.Conclusion: Citrus cultivars have some larvicidal potential but C. jambhiri had the greatest potential against A. ae­gypti larvae. Further small-scale field trials using the extracts of C. jambhiri will be conducted to determine opera­tional feasibility.

  13. Crystal clear: visualizing the intervention mechanism of the PD-1/PD-L1 interaction by two cancer therapeutic monoclonal antibodies

    Directory of Open Access Journals (Sweden)

    Shuguang Tan

    2016-11-01

    Full Text Available Abstract Antibody-based PD-1/PD-L1 blockade therapies have taken center stage in immunotherapies for cancer, with multiple clinical successes. PD-1 signaling plays pivotal roles in tumor-driven T-cell dysfunction. In contrast to prior approaches to generate or boost tumor-specific T-cell responses, antibody-based PD-1/PD-L1 blockade targets tumor-induced T-cell defects and restores pre-existing T-cell function to modulate antitumor immunity. In this review, the fundamental knowledge on the expression regulations and inhibitory functions of PD-1 and the present understanding of antibody-based PD-1/PD-L1 blockade therapies are briefly summarized. We then focus on the recent breakthrough work concerning the structural basis of the PD-1/PD-Ls interaction and how therapeutic antibodies, pembrolizumab targeting PD-1 and avelumab targeting PD-L1, compete with the binding of PD-1/PD-L1 to interrupt the PD-1/PD-L1 interaction. We believe that this structural information will benefit the design and improvement of therapeutic antibodies targeting PD-1 signaling.

  14. Resistance of developing honeybee larvae during chronic exposure to dietary nicotine.

    Science.gov (United States)

    Human, H; Archer, C R; du Rand, E E; Pirk, C W W; Nicolson, S W

    2014-10-01

    The effects of pesticides on honeybee larvae are less understood than for adult bees, even though larvae are chronically exposed to pesticide residues that accumulate in comb and food stores in the hive. We investigated how exposure to a plant alkaloid, nicotine, affects survival, growth and body composition of honeybee larvae. Larvae of Apis mellifera scutellata were reared in vitro and fed throughout development on standard diets with nicotine included at concentrations from 0 to 1000μg/100g diet. Overall mortality across all nicotine treatments was low, averaging 9.8% at the prepupal stage and 18.1% at the white-eyed pupal stage, but survival was significantly reduced by nicotine. The mass of prepupae and white-eyed pupae was not affected by nicotine. In terms of body composition, nicotine affected water content but did not influence either protein or lipid stores of white-eyed pupae. We attribute the absence of consistent negative effects of dietary nicotine to detoxification mechanisms in developing honeybees, which enable them to resist both natural and synthetic xenobiotics. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Acute toxicity of copper, zinc, and ammonia to larvae (Glochidia) of a native freshwater mussel Echyridella menziesii in New Zealand.

    Science.gov (United States)

    Clearwater, Susan J; Thompson, Karen J; Hickey, Christopher W

    2014-02-01

    Adult New Zealand freshwater mussel Echyridella menziesii were collected from three locations in the North Island of New Zealand. In a series of tests that followed standard test guidance, glochidia were exposed to either dissolved copper (Cu), zinc (Zn), or total ammonia nitrogen (TAN) for 6, 24, or 48 h (20 °C, pH 7.8, water hardness 30 mg L(-1) as CaCO3, dissolved organic carbon [DOC] 2.0-2.9 mg L(-1)). Of the three contaminants and tests that met control survival criteria, mussel larvae (glochidia) were most sensitive to Cu exposure (48-h EC50 = 1.7-3.4 μg L(-1), 48-h no observed effect concentrations (NOEC) of 1.3-2.6 μg L(-1)). The Zn 48-h EC50 concentrations were 229-337 μg L(-1) and the 48-h NOEC values were 128-240 μg L(-1). Compared with other native New Zealand species, glochidia were also relatively sensitive to TAN exposure (48-h EC50 12-15 mg TAN L(-1) [pH 7.8], 48-h NOEC 8-10 mg TAN L(-1)). Comparison of our data with those of previous studies on North American freshwater mussels indicates that (1) E. menziesii are among those aquatic species most sensitive to acute Cu or TAN exposure; and (2) E. menziesii juveniles would not be adequately protected by current ANZECC water quality guidelines for TAN or Cu. Inclusion of North American juvenile mussel data in a revision of the current ANZECC water-quality guideline (95th percentile) for chronic ammonia exposure results in a decrease from 0.9 mg to 0.2 mg TAN L(-1) (pH 8).

  16. Marine Invertebrate Larvae Associated with Symbiodinium: A Mutualism from the Start?

    KAUST Repository

    Mies, Miguel

    2017-05-30

    Symbiodinium are dinoflagellate photosynthetic algae that associate with a diverse array of marine invertebrates, and these relationships are comprehensively documented for adult animal hosts. Conversely, comparatively little is known about the associations during larval development of animal hosts, although four different metazoan phyla (Porifera, Cnidaria, Acoelomorpha, and Mollusca) produce larvae associated with Symbiodinium. These phyla represent considerable diversities in larval forms, manner of symbiont acquisition, and requirements on the presence of symbionts for successful metamorphosis. Importantly, the different requirements are conveyed by specific symbiont types that are selected by the host animal larvae. Nevertheless, it remains to be determined whether these associations during larval stages already represent mutualistic interactions, as evident from the relationship of Symbiodinium with their adult animal hosts. For instance, molecular studies suggest that the host larval transcriptome is nearly unaltered after symbiont acquisition. Even so, a symbiosis-specific gene has been identified in Symbiodinium that is expressed in larval host stages, and similar genes are currently being described for host organisms. However, some reports suggest that the metabolic exchange between host larvae and Symbiodinium may not cover the energetic requirements of the host. Here, we review current studies to summarize what is known about the association between metazoan larvae and Symbiodinium. In particular, our aim was to gather in how far the mutualistic relationship present between adult animals hosts and Symbiodinium is already laid out at the time of symbiont acquisition by host larvae. We conclude that the mutualistic relationship between animal hosts and algal symbionts in many cases is not set up during larval development. Furthermore, symbiont identity may influence whether a mutualism can be established during host larval stages.

  17. PD-L1 expression by neurons nearby tumors indicates better prognosis in glioblastoma patients

    DEFF Research Database (Denmark)

    Liu, Yawei; Carlsson, Robert; Ambjørn, Malene

    2013-01-01

    the functional consequences of neuronal Ifnb gene deletion on PD-L1 signaling and function. Ifnb-/- neurons lacked PD-L1 and were defective in inducing glioma cell death; this effect was reversed on PD-L1 gene transfection. Ifnb-/- mice with intracerebral isografts survived poorly. Similar to the observations...... and associated the findings with clinical outcome. Remarkably, we found that upregulation of PD-L1 by neurons in tumor-adjacent brain tissue (TABT) associated positively with GBM patient survival, whereas lack of neuronal PD-L1 expression was associated with high PD-L1 in tumors and unfavorable prognosis....... To understand the molecular mechanism of PD-L1 signaling in neurons, we investigated PD-L1 function in cerebellar and cortical neurons and its impact on gliomas. We discovered that neuronal PD-L1-induced caspase-dependent apoptosis of glioma cells. Because interferon (IFN)-β induces PD-L1 expression, we studied...

  18. Following the infection process of vibriosis in Manila clam (Ruditapes philippinarum) larvae through GFP-tagged pathogenic Vibrio species.

    Science.gov (United States)

    Dubert, Javier; Nelson, David R; Spinard, Edward J; Kessner, Linda; Gomez-Chiarri, Marta; da Costa, Fiz; Prado, Susana; Barja, Juan L

    2016-01-01

    Vibriosis represents the main bottleneck for the larval production process in shellfish aquaculture. While the signs of this disease in bivalve larvae are well known, the infection process by pathogenic Vibrio spp. during episodes of vibriosis has not been elucidated. To investigate the infection process in bivalves, the pathogens of larvae as V. tubiashii subsp. europaensis, V. neptunius and V. bivalvicida were tagged with green fluorescent protein (GFP). Larvae of Manila clam (Ruditapes philippinarum) were inoculated with the GFP-labeled pathogens in different infection assays and monitored by microscopy. Manila clam larvae infected by distinct GFP-tagged Vibrio spp. in different challenges showed the same progression in the infection process, defining three infection stages. GFP-tagged Vibrio spp. were filtered by the larvae through the vellum and entered in the digestive system through the esophagus and stomach and colonized the digestive gland and particularly the intestine, where they proliferated during the first 2h of contact (Stage I), suggesting a chemotactic response. Then, GFP-tagged Vibrio spp. expanded rapidly to the surrounding organs in the body cavity from the dorsal to ventral region (Stage II; 6-8h), colonizing the larvae completely at the peak of infection (Stage III) (14-24h). Results demonstrated for the first time that the vibriosis is asymptomatic in Manila clam larvae during the early infection stages. Thus, the early colonization and the rapid proliferation of Vibrio pathogens within the body cavity supported the sudden and fatal effect of the vibriosis, since the larvae exhibited the first signs of disease when the infection process is advanced. As a first step in the elucidation of the potential mechanisms of bacterial pathogenesis in bivalve larvae the enzymatic activities of the extracellular products released from the wild type V. neptunius, V. tubiashii subsp. europaensis and V. bivalvicida were determined and their cytotoxicity was

  19. First record of larvae of Hysterothylacium (Nematoda: Anisakidae) with zoonotic potential in the pirarucu Arapaima gigas (Osteichthyes: Arapaimidae) from South America.

    Science.gov (United States)

    Andrade-Porto, S M; Cárdenas, M Q; Martins, M L; Oliveira, J K Q; Pereira, J N; Araújo, C S O; Malta, J C O

    2015-11-01

    Third-stage larvae (L3) of Hysterothylacium sp. were collected by the first time in juveniles of pirarucu Arapaima gigas farmed in the Rio Preto da Eva, Amazonas state. Ninety-eight (98) out of 100 examined fish showed to be parasitized. Five hundred and ninety larvae of Hysterothylacium sp. were collected from the intestines, stomach and pyloric caeca. The mean intensity of parasite indexes was 6.02 (±5.75) ranging from 1 to 40 larvae per host and the mean abundance was 5.9 (±5.76). The A. gigas is the new host record for larvae of Hysterothylacium sp. in Brazil, and this is the first record of larvae of Hysterothylacium (Nematoda: Anisakidae) with zoonotic potential in the pirarucu from South America.

  20. Osmoregulation in larvae and juveniles of two recently separated Macrobrachium species: Expression patterns of ion transporter genes.

    Science.gov (United States)

    Boudour-Boucheker, Nesrine; Boulo, Viviane; Charmantier-Daures, Mireille; Anger, Klaus; Charmantier, Guy; Lorin-Nebel, Catherine

    2016-05-01

    In this comparative study, osmoregulatory mechanisms were analyzed in two closely related species of palaemonid shrimp from Brazil, Macrobrachium pantanalense and Macrobrachium amazonicum. A previous investigation showed that all postembryonic stages of M. pantanalense from inland waters of the Pantanal are able to hyper-osmoregulate in fresh water, while this species was not able to hypo-osmoregulate at high salinities. In M. amazonicum originating from the Amazon estuary, in contrast, all stages are able to hypo-osmoregulate, but only first-stage larvae, late juveniles and adults are able to hyper-osmoregulate in fresh water. The underlying molecular mechanisms of these physiological differences have not been known. We therefore investigated the expression patterns of three ion transporters (NKA α-subunit, VHA B-subunit and NHE3) following differential salinity acclimation in different ontogenetic stages (stage-V larvae, juveniles) of both species. Larval NKAα expression was at both salinities significantly higher in M. pantanalense than in M. amazonicum, whereas no difference was noted in juveniles. VHA was also more expressed in larvae of M. pantanalense than in those of M. amazonicum. When NHE3 expression is compared between the larvae of the two species, further salinity-related differences were observed, with generally higher expression in the inland species. Overall, a high expression of ion pumps in M. pantanalense suggests an evolutionary key role of these transporters in freshwater invasion. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Effect of Musa spp. extract on eggs and larvae of gastrointestinal nematodes from infected sheep

    Directory of Open Access Journals (Sweden)

    Natalie Neuwirt

    2015-12-01

    Full Text Available Helminthes are listed as one of the main problems facing the development of goat and sheep production. Haemonchus contortus is the specie that causes greatest negative impact in ranching. Resistance to anti-parasitic drugs and demand for residue-free animal-derived food products has elevated the importance of herbal treatments. The aim of this study was to develop an extract of Musa spp. and assess by in vitro testing, the anthelmintic effect on eggs and larvae in the gastrointestinal nematodes in sheep. Stool samples from sheep naturally infected were used to obtain eggs and larvae and was then followed by a test of hatchability and a larval migration inhibition test. In vitro tests on the inhibition of larval hatchability at concentrations of 160 and 180 mg mL-1 of larval extracts and inhibition of migration at concentrations of 800 and 1000 mg mL-1 were observed. The results indicate that the use of banana leaf has an anthelmintic effect and that in vivo studies on the applicability of this technology to the field should be made to further understanding and bring more information to what has already been revealed in this study.

  2. Localization of neuropeptide gene expression in larvae of an echinoderm, the starfish Asterias rubens

    Directory of Open Access Journals (Sweden)

    Tatiana D Mayorova

    2016-12-01

    Full Text Available Neuropeptides are an ancient class of neuronal signaling molecules that regulate a variety of physiological and behavioral processes in animals. The life cycle of many animals includes a larval stage(s that precedes metamorphic transition to a reproductively active adult stage but, with the exception of Drosophila melanogaster and other insects, research on neuropeptide signaling has hitherto largely focused on adult animals. However, recent advances in genome/transcriptome sequencing have facilitated investigation of neuropeptide expression/function in the larvae of protostomian (e.g. the annelid Platynereis dumerilii and deuterostomian (e.g. the urochordate Ciona intestinalis invertebrates. Accordingly, here we report the first multi-gene investigation of larval neuropeptide precursor expression in a species belonging to the phylum Echinodermata - the starfish Asterias rubens. Whole-mount mRNA in situ hybridization was used to visualize in bipinnaria and brachiolaria stage larvae the expression of eight neuropeptide precursors: L-type SALMFamide (S1, F-type SALMFamide (S2, vasopressin/oxytocin-type, NGFFYamide, thyrotropin-releasing hormone-type, gonadotropin-releasing hormone-type, calcitonin-type and corticotropin-releasing hormone-type. Expression of only three of the precursors (S1, S2, NGFFYamide was observed in bipinnaria larvae but by the brachiolaria stage expression of all eight precursors was detected. An evolutionarily conserved feature of larval nervous systems is the apical organ and in starfish larvae this comprises the bilaterally symmetrical lateral ganglia, but only the S1 and S2 precursors were found to be expressed in these ganglia. A prominent feature of brachiolaria larvae is the attachment complex, comprising the brachia and adhesive disk, which mediates larval attachment to a substratum prior to metamorphosis. Interestingly, all of the neuropeptide precursors examined here are expressed in the attachment complex, with

  3. Localization of Neuropeptide Gene Expression in Larvae of an Echinoderm, the Starfish Asterias rubens.

    Science.gov (United States)

    Mayorova, Tatiana D; Tian, Shi; Cai, Weigang; Semmens, Dean C; Odekunle, Esther A; Zandawala, Meet; Badi, Yusef; Rowe, Matthew L; Egertová, Michaela; Elphick, Maurice R

    2016-01-01

    Neuropeptides are an ancient class of neuronal signaling molecules that regulate a variety of physiological and behavioral processes in animals. The life cycle of many animals includes a larval stage(s) that precedes metamorphic transition to a reproductively active adult stage but, with the exception of Drosophila melanogaster and other insects, research on neuropeptide signaling has hitherto largely focused on adult animals. However, recent advances in genome/transcriptome sequencing have facilitated investigation of neuropeptide expression/function in the larvae of protostomian (e.g., the annelid Platynereis dumerilii ) and deuterostomian (e.g., the urochordate Ciona intestinalis ) invertebrates. Accordingly, here we report the first multi-gene investigation of larval neuropeptide precursor expression in a species belonging to the phylum Echinodermata-the starfish Asterias rubens . Whole-mount mRNA in situ hybridization was used to visualize in bipinnaria and brachiolaria stage larvae the expression of eight neuropeptide precursors: L-type SALMFamide (S1), F-type SALMFamide (S2), vasopressin/oxytocin-type, NGFFYamide, thyrotropin-releasing hormone-type, gonadotropin-releasing hormone-type, calcitonin-type and corticotropin-releasing hormone-type. Expression of only three of the precursors (S1, S2, NGFFYamide) was observed in bipinnaria larvae but by the brachiolaria stage expression of all eight precursors was detected. An evolutionarily conserved feature of larval nervous systems is the apical organ and in starfish larvae this comprises the bilaterally symmetrical lateral ganglia, but only the S1 and S2 precursors were found to be expressed in these ganglia. A prominent feature of brachiolaria larvae is the attachment complex, comprising the brachia and adhesive disk, which mediates larval attachment to a substratum prior to metamorphosis. Interestingly, all of the neuropeptide precursors examined here are expressed in the attachment complex, with distinctive

  4. PEMELIHARAAN LARVA KEPITING BAKAU, Scylla olivacea DENGAN PENAMBAHAN BIOFLOK

    Directory of Open Access Journals (Sweden)

    Gunarto Gunarto

    2014-06-01

    Full Text Available Abstrak lengkap dapat dilihat pada Full PDF   Tujuan penelitian ini adalah untuk mengetahui efek penambahan bioflok pada pemeliharaan larva kepiting bakau Scylla olivacea terutaman pada sintasan dan perkembangan larva hingga mencapai stadia krablet.

  5. Nutritional condition and vertical distribution of Baltic cod larvae

    DEFF Research Database (Denmark)

    Grønkjær, P.; Clemmesen, C.; St. John, Michael

    1997-01-01

    Newly hatched Baltic cod Gadus morhua larvae are typically found at depths >60 m. This is a region of low light and prey availability, hence generating the hypothesis that larvae have to migrate from hatching depth to the surface layer to avoid starvation and improve their nutritional condition....... To lest this hypothesis, Baltic cod larvae were sampled during the spawning seasons of 1994 and 1995 with depth-resolving multiple opening/closing nets. Each larva was aged by otolith readings and its RNA/DNA ratio was determined as a measure of nutritional condition. The RNA/DNA ratios of these larvae...... caught larvae had RNA/DNA ratios between the mean values found for starving and fed laboratory larvae. Only larvae aged 8-11 days had higher mean RNA/DNA ratios above 45 m than below (t-test, P...

  6. CalCOFI Larvae Counts, Scientific Names HB to HI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  7. CalCOFI Larvae Counts, Scientific Names CP to DE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  8. CalCOFI Larvae Counts, Scientific Names OM to OX

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  9. CalCOFI Larvae Counts, Scientific Names SB to SC

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  10. Decapod larvae from the nearshore waters of Karwar

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.; Paulinose, V.T.

    Abundance of decapod larvae at three stations in Binge Bay, Karwar has been reported based on surface collections taken during the period October 1975 to September 1976. The larvae were very common in the Bay and the postmonsoon months sustained...

  11. CalCOFI Larvae Counts, Scientific Names DH to EC

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Fish larvae counts and standardized counts for larvae captured in CalCOFI icthyoplankton nets (primarily vertical [Calvet or Pairovet], oblique [bongo or ring nets],...

  12. Suppressing bullfrog larvae with carbon dioxide

    Science.gov (United States)

    Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert,; ,

    2014-01-01

    Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

  13. Low salinity tolerance 0/ eggs and larvae.

    African Journals Online (AJOL)

    the larvae permitting C. krauss; to spread into areas where it is unable to breed successfully. ACKNOWLEDGEMENTS. The author acknowledges the financial assistance of the Department of Nature Conserva- tion of the Cape Province of South Africa, and the South African National Committee for. Oceanographic Research ...

  14. Dietary xenoestrogens differentially impair 3T3-L1 preadipocyte differentiation and persistently affect leptin synthesis.

    Science.gov (United States)

    Phrakonkham, Pascal; Viengchareun, Say; Belloir, Christine; Lombès, Marc; Artur, Yves; Canivenc-Lavier, Marie-Chantal

    2008-05-01

    Recent observations have highlighted adipogenesis alterations under exposure to several xenoestrogens at critical stages, and pointed at their possible involvement in the pathogenesis of obesity. However, it remains unclear whether these effects are mediated by classical estrogen receptor (ER) binding and subsequent transcriptional modulation. The aim of this study was to determine the (anti-)adipogenic impact of apigenin, bisphenol A, genistein and 17beta-estradiol at the onset of adipose cell maturation, and to correlate it to their estrogenic potential. In steroid-free conditions, 3T3-L1 preadipocytes were induced to differentiate in the presence of xenoestrogens for 2 days. DNA and triglyceride levels, leptin secretion and expression of Pref-1, C/EBPbeta, PPARgamma2, FAS, leptin and ERs were measured on days 0, 3 and 8 of differentiation. Genistein potently blocked mitotic clonal expansion and all markers of maturation. Bisphenol A and estradiol did not modify triglyceride accumulation but increased the expression of differentiation genes. Apigenin caused a weak but reversible delay in adipogenesis although it unexpectedly enhanced leptin synthesis. However, the expression of steroid hormone receptors was not associated with these differential effects. In conclusion, we could not put a clear estrogen-dependent mechanism forward, but early exposure to xenoestrogens persistently disrupted adipocyte gene expression and leptin synthesis.

  15. Effects of Methylmercury exposure in 3T3-L1 Adipocytes

    Directory of Open Access Journals (Sweden)

    Theresa Vertigan

    2017-02-01

    Full Text Available Mercury-containing compounds are environmental pollutants that have become increasingly consequential in the Arctic regions of North America due to processes of climate change increasing their release and availability at northern latitudes. Currently, the form of mercury known to be most detrimental to human health is methylmercury, CH3Hg+, which is found in the environment and accumulates in the tissues of piscivores, including those consumed by Alaska Natives through subsistence gathering. Much is known about the neurotoxicity of methylmercury after exposure to high concentrations, but little is known about toxicity to other tissues and cell types, particularly for long-term exposure and the lower concentrations that would occur through fish consumption. Effects of methylmercury exposure on 3T3-L1 adipocytes in culture were assessed using assays for cytotoxicity and an ELISA assay for vascular endothelial growth factor (VEGF, a signaling molecule shown to be important for maintaining metabolic status in adipose tissue. Results showed that exposure to methylmercury leads to significant toxicity in adipocytes at exposures of 100 ng/mL during later stages of differentiation, but lower methylmercury concentrations produced little to no toxicity. Results also showed that VEGF secretion is elevated in adipocytes exposed to methylmercury after the process of differentiating into mature, fat-storing cells. These results provide a basis for further exploration into metabolic consequences of methylmercury exposure on specific cell types and cell models.

  16. L1Track a fast Level 1 track trigger for the ATLAS High Luminosity Upgrade

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00050967

    2016-01-01

    With the planned high-luminosity upgrade of the LHC (HL-LHC), the ATLAS detector will see its collision rate increase by approximately a factor of 5 with respect to the current LHC operation. The earliest hardware based ATLAS trigger stage ("Level 1") will have to provide an higher rejection factor in a more difficult environment: a new improved Level 1 trigger architecture is under study, which includes the possibility of extracting with low latency and hight accuracy tracking information on time for the decision taking process. The expected trigger rates at HL-LHC and the available latency are the key ingredients that will drive the new design. The Level 1 track trigger (L1Track) design requires substantial modification of the ATLAS silicon detector readout philosophy: a precursor of the potential merging of detector and trigger architectures in the future silicon detectors at particle colliders. We will discuss potential approaches that are being actively considered to fulfil the demanding HL-LHC constrain...

  17. How Does L1 and L2 Exposure Impact L1 Performance in Bilingual Children? Evidence from Polish-English Migrants to the United Kingdom

    Science.gov (United States)

    Haman, Ewa; Wodniecka, Zofia; Marecka, Marta; Szewczyk, Jakub; Białecka-Pikul, Marta; Otwinowska, Agnieszka; Mieszkowska, Karolina; Łuniewska, Magdalena; Kołak, Joanna; Miękisz, Aneta; Kacprzak, Agnieszka; Banasik, Natalia; Foryś-Nogala, Małgorzata

    2017-01-01

    Most studies on bilingual language development focus on children’s second language (L2). Here, we investigated first language (L1) development of Polish-English early migrant bilinguals in four domains: vocabulary, grammar, phonological processing, and discourse. We first compared Polish language skills between bilinguals and their Polish non-migrant monolingual peers, and then investigated the influence of the cumulative exposure to L1 and L2 on bilinguals’ performance. We then examined whether high exposure to L1 could possibly minimize the gap between monolinguals and bilinguals. We analyzed data from 233 typically developing children (88 bilingual and 145 monolingual) aged 4;0 to 7;5 (years;months) on six language measures in Polish: receptive vocabulary, productive vocabulary, receptive grammar, productive grammar (sentence repetition), phonological processing (non-word repetition), and discourse abilities (narration). Information about language exposure was obtained via parental questionnaires. For each language task, we analyzed the data from the subsample of bilinguals who had completed all the tasks in question and from monolinguals matched one-on-one to the bilingual group on age, SES (measured by years of mother’s education), gender, non-verbal IQ, and short-term memory. The bilingual children scored lower than monolinguals in all language domains, except discourse. The group differences were more pronounced on the productive tasks (vocabulary, grammar, and phonological processing) and moderate on the receptive tasks (vocabulary and grammar). L1 exposure correlated positively with the vocabulary size and phonological processing. Grammar scores were not related to the levels of L1 exposure, but were predicted by general cognitive abilities. L2 exposure negatively influenced productive grammar in L1, suggesting possible L2 transfer effects on L1 grammatical performance. Children’s narrative skills benefitted from exposure to two languages: both L1

  18. UCH-L1 induces podocyte hypertrophy in membranous nephropathy by protein accumulation.

    Science.gov (United States)

    Lohmann, Frithjof; Sachs, Marlies; Meyer, Tobias N; Sievert, Henning; Lindenmeyer, Maja T; Wiech, Thorsten; Cohen, Clemens D; Balabanov, Stefan; Stahl, R A K; Meyer-Schwesinger, Catherine

    2014-07-01

    Podocytes are terminally differentiated cells of the glomerular filtration barrier that react with hypertrophy in the course of injury such as in membranous nephropathy (MGN). The neuronal deubiquitinase ubiquitin C-terminal hydrolase L1 (UCH-L1) is expressed and activated in podocytes of human and rodent MGN. UCH-L1 regulates the mono-ubiquitin pool and induces accumulation of poly-ubiquitinated proteins in affected podocytes. Here, we investigated the role of UCH-L1 in podocyte hypertrophy and in the homeostasis of the hypertrophy associated "model protein" p27(Kip1). A better understanding of the basic mechanisms leading to podocyte hypertrophy is crucial for the development of specific therapies in MGN. In human and rat MGN, hypertrophic podocytes exhibited a simultaneous up-regulation of UCH-L1 and of cytoplasmic p27(Kip1) content. Functionally, inhibition of UCH-L1 activity and knockdown or inhibition of UCH-L1 attenuated podocyte hypertrophy by decreasing the total protein content in isolated glomeruli and in cultured podocytes. In contrast, UCH-L1 levels and activity increased podocyte hypertrophy and total protein content in culture, specifically of cytoplasmic p27(Kip1). UCH-L1 enhanced cytoplasmic p27(Kip1) levels by nuclear export and decreased poly-ubiquitination and proteasomal degradation of p27(Kip1). In parallel, UCH-L1 increased podocyte turnover, migration and cytoskeletal rearrangement, which are associated with known oncogenic functions of cytoplasmic p27(Kip1) in cancer. We propose that UCH-L1 induces podocyte hypertrophy in MGN by increasing the total protein content through altered degradation and accumulation of proteins such as p27(Kip1) in the cytoplasm of podocytes. Modification of both UCH-L1 activity and levels could be a new therapeutic avenue to podocyte hypertrophy in MGN. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Purification and Characterization of Recombinant Vaccinia L1R Protein from Escherichia coli

    Science.gov (United States)

    2016-08-01

    Vaccinia surface protein, L1R, is critical for viral entry into host cells, and because of its close similarity to its smallpox counterpart, it is a...Chromatography Antigen 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON...Escherichia coli. 1.3 VACV L1R Protein VACV L1R is a conserved component of the viral envelope that plays a major role in viral entry at the host

  20. The Effects of L2 Reading Skills on L1 Reading Skills through Transfer

    Science.gov (United States)

    Altmisdort, Gonca

    2016-01-01

    This study investigated whether transfer from L2 to L1 in reading occurs, and if so, which reading sub-skills are transferred into L1 reading. The aim is to identify the role of second language reading skills in L1 reading skills by means of transfer. In addition, the positive effects of the second language transfer to the first language in the…

  1. Performance of Anastrepha obliqua (Diptera, Tephritidae larvae fed on artificial diets Desempenho das larvas de Anastrepha obliqua (Diptera, Tephritidae alimentadas com dietas artificiais

    Directory of Open Access Journals (Sweden)

    Tânia M. L. Fontellas-Brandalha

    2010-06-01

    Full Text Available Moscas das frutas do gênero Anastrepha Schiner, 1868 são conhecidas por sua importância econômica devido aos danos que elas causam nos frutos comerciais. As exigências nutricionais dos estágios imaturo e adulto são diferentes e as larvas não se desenvolvem bem utilizando a mesma dieta do adulto. Embora as necessidades nutricionais básicas dos insetos sejam bem conhecidas, existe ainda o problema de elaborar dietas de criação adequadas para espécies com necessidades específicas. O objetivo deste trabalho foi verificar o efeito de diferentes tipos e quantidades de carboidratos na dieta sobre a performance larval de Anastrepha obliqua (Macquart, 1835. Larvas foram criadas individualmente em tubos de ensaio contendo uma das dietas artificiais a serem testadas onde elas foram mantidas até a pupação. A composição básica das dietas testadas incluia 2,5 g de agar, 3,25 g de levedo de cerveja e quantidades variadas de sacarose e farinha de trigo. A adequação do meio artificial para A. obliqua foi testada pela avaliação da sobrevivência larval e pupal (% e o tempo de desenvolvimento larval, pupal e de larva-adulto. A dieta contendo farinha de trigo (2 g e sacarose (2 g e a dieta somente com sacarose (5,5 g foram as que apresentaram melhor performance larval. Todas as dietas testadas apresentaram resultados similares ou superiores às dietas utilizadas em outros trabalhos. A importância da presença da farinha de trigo e seu valor nutricional para as larvas são discutidos.Fruit flies of the genus Anastrepha Schiner, 1868 are well-known for having economical importance since they damage commercially cultivated fruits. Nutritional demands during the immature and adult stages are different, so the larvae do not develop well using the same diet as the adults. Although the insect basic nutritional needs are well-known, there is also the challenge to elaborate rearing diets adequate to species with specific needs. The aim of this study

  2. MiR-200c-5p suppresses proliferation and metastasis of human hepatocellular carcinoma (HCC) via suppressing MAD2L1.

    Science.gov (United States)

    Li, Yuanhang; Bai, Weijun; Zhang, Jianjun

    2017-08-01

    To explore the biological functions of miR-200c-5p/MAD2L1 axis on the proliferation and metastasis of human hepatocellular carcinoma (HCC) cells. The expression levels of miR-200c-5p and MAD2L1 in HCC tissues, adjacent tissues as well as HCC cell lines were detected by RT-qPCR or Western blot. The interaction between miR-200c-5p and MAD2L1 was verified by dual luciferase reporter gene system. Transfection was performed to manipulate the expression of miR-200c-5p and MAD2L1 in HCCLM3 cells. Colony formation, MTT, wound healing and Transwell assays were applied to measure the cell proliferation, migration and invasion of HCC, besides, flow cytometry analysis was also conducted to evaluate HCC cell cycle and apoptosis. Low expression of miR-200c-5p and remarkable overexpression of MAD2L1 was uncovered in HCC tissues and cells compared with the normal. The aberrant expression of miR-200c-5p and MAD2L1 was correlated with tumor stage, adjacent organ invasion and prognosis. Direct target relationship between miR-200c-5p and MAD2L1 was confirmed by dual luciferase reporting assay. Up-regulation of miR-200c-5p downregulated MAD2L1 and suppressed the proliferation, migration, invasion and induced apoptosis and cell cycle arrest of HCC cells. Moreover, MAD2L1 promoted HCC cell viabilities and co-transfection of MAD2L1 restored the anti-tumor effects of miR-200c-5p overexpression. Replenishing of miR-200c-5p inhibited the proliferation, migration and invasion of HCC cells by suppressing MAD2L1. MiR-200c-5p can serve as a prognostic indicator and a promising therapeutic target for HCC patients. Copyright © 2017. Published by Elsevier Masson SAS.

  3. ISOLASI BACILLUS THURINGIENSIS DARI LARVA DAN PENGUJIAN PATOGENISITASNYA TERHADAP LARVA NYAMUK VEKTOR

    Directory of Open Access Journals (Sweden)

    Blondine Ch. P.

    2012-09-01

    Full Text Available A study to evaluate pathogenic organisms as cause of mosquito larvae death was conducted at Wonokerto and Pabelan villages, Salatiga Luar Kota subdistrict, Semarang regency in Central Java from May 1991 through December 1991. Bacterial isolation from dead larvae showed that 31 B. thuringicnsis isolates were obtained from 31 larvae samples collected from 2 location e.g Wonokerto village (3 samples, Pabelan village (28 samples. Nineteen isolates (61,3% showed a pathogenicity of more than 50% to third toward instar larvae of Aedes aegypti and Culex quinquefasciatus respectively 24 hours after exposure. This study shows the possible use of B. thuringiensis for biologic control of mosquitoes which can act as vectors for human diseases.

  4. A comparison of honeybee (Apis mellifera) queen, worker and drone larvae by RNA-Seq.

    Science.gov (United States)

    He, Xu-Jiang; Jiang, Wu-Jun; Zhou, Mi; Barron, Andrew B; Zeng, Zhi-Jiang

    2017-11-06

    Honeybees (Apis mellifera) have haplodiploid sex determination: males develop from unfertilized eggs and females develop from fertilized ones. The differences in larval food also determine the development of females. Here we compared the total somatic gene expression profiles of 2-day and 4-day-old drone, queen and worker larvae by RNA-Seq. The results from a co-expression network analysis on all expressed genes showed that 2-day-old drone and worker larvae were closer in gene expression profiles than 2-day-old queen larvae. This indicated that for young larvae (2-day-old) environmental factors such as larval diet have a greater effect on gene expression profiles than ploidy or sex determination. Drones had the most distinct gene expression profiles at the 4-day larval stage, suggesting that haploidy, or sex dramatically affects the gene expression of honeybee larvae. Drone larvae showed fewer differences in gene expression profiles at the 2-day and 4-day time points than the worker and queen larval comparisons (598 against 1190 and 1181), suggesting a different pattern of gene expression regulation during the larval development of haploid males compared to diploid females. This study indicates that early in development the queen caste has the most distinct gene expression profile, perhaps reflecting the very rapid growth and morphological specialization of this caste compared to workers and drones. Later in development the haploid male drones have the most distinct gene expression profile, perhaps reflecting the influence of ploidy or sex determination on gene expression. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  5. Laboratory evolution of the entomopathogenic fungus Beauveria bassiana against Anopheles stephensi larvae (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Rahele Veys-Behbahani

    2014-09-01

    Full Text Available Objective: To examine Beauveria bassiana (B. bassiana fungus bioassay against the larval stages of Anopheles stephensi in Iran. Methods: The fungal suspension by the concentrations of 1伊1 09, 5伊1 08, 1 08, 5伊1 07 and 1伊 107 conidia per milliliter have been prepared in different volumes (2, 4 and 6 mL and each concentration were added to containers containing 25 Anopheles larva instars 1 and 2. The mortality of the dead larvae with abnormal symptoms was recorded as a result of the fungal infection after 24, 48 and 72 h. Results: Comparison between the mean mortality rate of Anopheles stephensi larva at different concentrations of B. bassiana strain Iran 429C at 2, 4 and 6 mL showed that there was no significant relation of the mean mortality rate of larvae at concentrations of 1伊109 and 5伊108, and after 48 h resulted in 100% mortality rate of the larvae populations. In addition, there is no significant differences in the amounts of lethal times (LT (LT50 and LT90 as LT90 values calculated at a concentration of 5伊108 and in volumes 2, 4 and 6 mL were 1.46, 1.36 and 1.08 d, respectively. Conclusions: B. bassiana strain Iran 429C in 2 mL of 5伊108 concentration or the concentration of a 1伊109 mL per 100 mL of water is recommended as the optimal concentration for the control of Anopheles larvae. The development of suitable formulations of entomopathogenic fungi may be a promising prospect in the mosquito control programs.

  6. L1 AND L2 GLOSSES: THEIR EFFECTS ON INCIDENTAL VOCABULARY LEARNING

    OpenAIRE

    Makoto Yoshii

    2006-01-01

    This study examined the effectiveness of L1 and L2 glosses on incidental vocabulary learning in a multimedia environment. The investigation included the effects of additional pictorial cues in L1 and L2 glosses, and how these additions affect vocabulary learning. The analyses of a mixed design repeated measures 2 (L1, L2) X 2 (picture, no picture) X 2 (immediate test, delayed test) analysis of variance (ANOVA) indicated no significant differences between L1 and L2 glosses for definition-suppl...

  7. Combining Amplification Typing of L1 Active Subfamilies (ATLAS) with High-Throughput Sequencing.

    Science.gov (United States)

    Rahbari, Raheleh; Badge, Richard M

    2016-01-01

    With the advent of new generations of high-throughput sequencing technologies, the catalog of human genome variants created by retrotransposon activity is expanding rapidly. However, despite these advances in describing L1 diversity and the fact that L1 must retrotranspose in the germline or prior to germline partitioning to be evolutionarily successful, direct assessment of de novo L1 retrotransposition in the germline or early embryogenesis has not been achieved for endogenous L1 elements. A direct study of de novo L1 retrotransposition into susceptible loci within sperm DNA (Freeman et al., Hum Mutat 32(8):978-988, 2011) suggested that the rate of L1 retrotransposition in the germline is much lower than previously estimated (ATLAS L1 display technique (Badge et al., Am J Hum Genet 72(4):823-838, 2003) to investigate de novo L1 retrotransposition in human genomes. In this chapter, we describe how we combined a high-coverage ATLAS variant with high-throughput sequencing, achieving 11-25× sequence depth per single amplicon, to study L1 retrotransposition in whole genome amplified (WGA) DNAs.

  8. Univariate Cubic L1 Interpolating Splines: Spline Functional, Window Size and Analysis-based Algorithm

    Directory of Open Access Journals (Sweden)

    Shu-Cherng Fang

    2010-08-01

    Full Text Available We compare univariate L1 interpolating splines calculated on 5-point windows, on 7-point windows and on global data sets using four different spline functionals, namely, ones based on the second derivative, the first derivative, the function value and the antiderivative. Computational results indicate that second-derivative-based 5-point-window L1 splines preserve shape as well as or better than the other types of L1 splines. To calculate second-derivative-based 5-point-window L1 splines, we introduce an analysis-based, parallelizable algorithm. This algorithm is orders of magnitude faster than the previously widely used primal affine algorithm.

  9. L1 increases adhesion-mediated proliferation and chemoresistance of retinoblastoma.

    Science.gov (United States)

    Jo, Dong Hyun; Lee, Kyungmin; Kim, Jin Hyoung; Jun, Hyoung Oh; Kim, Younghoon; Cho, Young-Lai; Yu, Young Suk; Min, Jeong-Ki; Kim, Jeong Hun

    2017-02-28

    Retinoblastoma is the most common intraocular cancer in children, affecting 1/20,000 live births. Currently, children with retinoblastoma were treated with chemotherapy using drugs such as carboplatin, vincristine, and etoposide. Unfortunately, if conventional treatment fails, the affected eyes should be removed to prevent extension into adjacent tissues and metastasis. This study is to investigate the roles of L1 in adhesion-mediated proliferation and chemoresistance of retinoblastoma. L1 was differentially expressed in 30 retinoblastoma tissues and 2 retinoblastoma cell lines. Furthermore, the proportions of L1-positive cells in retinoblastoma tumors were negatively linked with the number of Flexner-Wintersteiner rosettes, a characteristic of differentiated retinoblastoma tumors, in each tumor sample. Following in vitro experiments using L1-deleted and -overexpressing cells showed that L1 increased adhesion-mediated proliferation of retinoblastoma cells via regulation of cell cycle-associated proteins with modulation of Akt, extracellular signal-regulated kinase, and p38 pathways. In addition, L1 increased resistance against carboplatin, vincristine, and esoposide through up-regulation of apoptosis- and multidrug resistance-related genes. In vivo tumor formation and chemoresistance were also positively linked with the levels of L1 in an orthotopic transplantation model in mice. In this manner, L1 increases adhesion-mediated proliferation and chemoresistance of retinoblastoma. Targeted therapy to L1 might be effective in the treatment of retinoblastoma tumors, especially which rapidly proliferate and demonstrate resistance to conventional chemotherapeutic drugs.

  10. Hepatic NPC1L1 overexpression ameliorates glucose metabolism in diabetic mice via suppression of gluconeogenesis.

    Science.gov (United States)

    Kurano, Makoto; Hara, Masumi; Satoh, Hiroaki; Tsukamoto, Kazuhisa

    2015-05-01

    Inhibition of intestinal NPC1L1 by ezetimibe has been demonstrated to improve glucose metabolism in rodent models; however, the role of hepatic NPC1L1 in glucose metabolism has not been elucidated. In this study, we analyzed the effects of hepatic NPC1L1 on glucose metabolism. We overexpressed NPC1L1 in the livers of lean wild type mice, diet-induced obesity mice and db/db mice with adenoviral gene transfer. We found that in all three mouse models, hepatic NPC1L1 overexpression lowered fasting blood glucose levels as well as blood glucose levels on ad libitum; in db/db mice, hepatic NPC1L1 overexpression improved blood glucose levels to almost the same as those found in lean wild type mice. A pyruvate tolerance test revealed that gluconeogenesis was suppressed by hepatic NPC1L1 overexpression. Further analyses revealed that hepatic NPC1L1 overexpression decreased the expression of FoxO1, resulting in the reduced expression of G6Pase and PEPCK, key enzymes in gluconeogenesis. These results indicate that hepatic NPC1L1 might have distinct properties of suppressing gluconeogenesis via inhibition of FoxO1 pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. PD-L1 gene polymorphisms and low serum level of PD-L1 protein are associated to type 1 diabetes in Chile.

    Science.gov (United States)

    Pizarro, Carolina; García-Díaz, Diego F; Codner, Ethel; Salas-Pérez, Francisca; Carrasco, Elena; Pérez-Bravo, Francisco

    2014-11-01

    Type 1 diabetes (T1D) has a complex etiology in which genetic and environmental factors are involved, whose interactions have not yet been completely clarified. In this context, the role in PD-1 pathway and its ligands 1 and 2 (PD-L1 and PD-L2) have been proposed as candidates in several autoimmune diseases. The aim of this work was to determine the allele and haplotype frequency of six gene polymorphisms of PD-ligands (PD-L1 and PD-L2) in Chilean T1D patients and their effect on serum levels of PD-L1 and autoantibody profile (GAD65 and IA2). This study cohort comprised 205 T1D patients and 205 normal children. We performed genotypic analysis of PD-L1 and PD-L2 genes by TaqMan method. Determination of anti-GAD65 and anti-IA-2 autoantibodies was performed by ELISA. The PD-L1 serum levels were measured. The allelic distribution of PD-L1 variants (rs2297137 and rs4143815) showed differences between T1D patients and controls (p = 0.035 and p = 0.022, respectively). No differences were detected among the PD-L2 polymorphisms, and only the rs16923189 showed genetic variation. T1D patients showed decreased serum levels of PD-L1 compared to controls: 1.42 [0.23-7.45] ng/mL versus 3.35 [0.49-5.89] ng/mL (p diabetics patients. Moreover, the age of onset of the disease determine differences between serum ligand levels in diabetics, being lower in younger. These results points to a possible establishment of PDL-1 as a genetic and biochemical marker for T1D onset, at least in Chilean population. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Feeding frequency and caste differentiation in Bombus terrestris larvae

    NARCIS (Netherlands)

    Ribeiro, M.F.; Velthuis, H.H.W.; Duchateau, Marie José; Tweel, I. van der

    1998-01-01

    The frequency with which bumble bee larvae are fed during their development was studied using video-recordings. The behaviour of the workers while feeding worker, male and queen larvae of Bombus terrestris was recorded. At the beginning of development, female larvae of both castes were fed at a

  13. Odour avoidance learning in the larva of Drosophila melanogaster

    Indian Academy of Sciences (India)

    Prakash

    with electric shock in normal and mutant larvae and Tully et al. reported the passage of olfactory ... Drosophila larvae can be trained to avoid odours associated with electric shock. We describe here, an improved method of ..... Pairing odour with shock drives the larvae to the opposite zone. Preference learning index PLI.

  14. Lethal infection thresholds of Paenibacillus larvae for honeybee drone and worker larvae (Apis mellifera).

    Science.gov (United States)

    Behrens, Dieter; Forsgren, Eva; Fries, Ingemar; Moritz, Robin F A

    2010-10-01

    We compared the mortality of honeybee (Apis mellifera) drone and worker larvae from a single queen under controlled in vitro conditions following infection with Paenibacillus larvae, a bacterium causing the brood disease American Foulbrood (AFB). We also determined absolute P. larvae cell numbers and lethal titres in deceased individuals of both sexes up to 8 days post infection using quantitative real-time PCR (qPCR). Our results show that in drones the onset of infection induced mortality is delayed by 1 day, the cumulative mortality is reduced by 10% and P. larvae cell numbers are higher than in worker larvae. Since differences in bacterial cell titres between sexes can be explained by differences in body size, larval size appears to be a key parameter for a lethal threshold in AFB tolerance. Both means and variances for lethal thresholds are similar for drone and worker larvae suggesting that drone resistance phenotypes resemble those of related workers. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

  15. Respon Imun Spesifik Larva Ikan Mas (Cyprinus carpio melalui Imunitas Maternal yang Diberi Vaksin Inaktif Whole Cell Aeromonas salmonicida

    Directory of Open Access Journals (Sweden)

    Syohibahttul Islamiyah BAHAR

    2017-02-01

    Full Text Available Aeromonas salmonicida are specific bacteria that can cause infections and death to the cultivation of carp (Cyprinus carpio during larval stage. Death in carp can be prevented by a vaccine, but the vaccine can only be given on the seed over the age of 3 weeks. Maternal vaccination needs to be done to improve the immune system of the larvae by means of inactivated whole cell vaccine A. salmonicida on broodstock ready to spawn. Aims to determine the effectiveness of vaccines on breeders carp to the parent antibody titer test and larvae, as well Survival Rate (SR and the Relative Percent Survival (RPS larvae. This research was conducted with a completely randomized design, 4 treatments A (control; B (0.3 ml/kg; C (0.4 ml/kg; D (0.5 ml/kg and 3 repetitions. The results show that the antibody titer of 0.3 ml dose capable of providing agglutination reaction to pitting 7th (64x dilution in broodstock, and vaccine doses 0,4ml on broodstock able to give agglutination reaction to the larvae until all 6 wells (32x dilution. A dose of 0.4 ml/kg resulted the highest SR and RPS with 96.11% and 81.25% respectively. Clinical symptoms of redness in control larvae was spread throughout the body whereas on the vaccine treatment was only in certain body parts. Keywords: A. salmonicida, vaccines, maternal immunity, larva, specific immune respon

  16. Lipid metabolism-related gene expression pattern of Atlantic bluefin tuna (Thunnus thynnus L.) larvae fed on live prey.

    Science.gov (United States)

    Betancor, Mónica B; Ortega, Aurelio; de la Gándara, Fernando; Tocher, Douglas R; Mourente, Gabriel

    2017-04-01

    The present study is the first to evaluate lipid metabolism in first-feeding Atlantic bluefin tuna (ABT; Thunnus thynnus L.) larvae fed different live prey including enriched rotifers Brachionus plicatilis and Acartia sp. copepod nauplii from 2 days after hatch. Understanding the molecular basis of lipid metabolism and regulation in ABT will provide insights to optimize diet formulations for this high-value species new to aquaculture. To this end, we investigated the effect of dietary lipid on whole larvae lipid class and fatty acid compositions and the expression of key genes involved in lipid metabolism in first feeding ABT larvae fed different live prey. Additionally, the expression of lipid metabolism genes in tissues of adult broodstock ABT was evaluated. Growth and survival data indicated that copepods were the best live prey for first feeding ABT and that differences in growth performance and lipid metabolism observed between larvae from different year classes could be a consequence of broodstock nutrition. In addition, expression patterns of lipid metabolic genes observed in ABT larvae in the trials could reflect differences in lipid class and fatty acid compositions of the live prey. The lipid nutritional requirements, including essential fatty acid requirements of larval ABT during the early feeding stages, are unknown, and the present study represents a first step in addressing these highly relevant issues. However, further studies are required to determine nutritional requirements and understand lipid metabolism during development of ABT larvae and to apply the knowledge to the commercial culture of this iconic species.

  17. Histopathology of experimental myiasis in mice as a result of infestation and experimental implantation of Dermatobia hominis larvae.

    Science.gov (United States)

    Leite, A C R; Nascimento, M F A; Leite, L H R; Leite, V H R

    2011-05-01

    A laboratory model of myiasis as a result of Dermatobia hominis (L.) larvae was developed using mice as hosts. Mice in three groups were each infested with one newly hatched larva and skin biopsies processed for histopathology at 4, 12, and 20 d postinfestation (dpi). Mice in three other groups were each subjected to implantation of one larva collected from an infested (donor) mouse at 4, 12, and 20 dpi. Skin lesions of these receptor mice were then assessed at 10, 14, and 6 d postimplantation (dpimp), respectively. The inflammatory process in infested mice at 4 dpi was discrete, consisting of a thin necrotic layer around the larva, edema, many neutrophils, few eosinophils, mast cells, and proliferation of fibroblasts. At 12 dpi, there was a thicker necrotic layer, edema, many neutrophils and eosinophils, few mast cells, neoformation of capillaries, proliferation of the endothelium and fibroblasts, and early stages of fibrosis. These histopathological characteristics together with fibrosis were observed over a large area of the lesion at 20 dpi. Mice submitted to larval implantations demonstrated similar skin histopathology to that seen in the infested rodents, 10 dpimp corresponding to 12 dpi and 6 or 14 dpimp to 20 dpi. In all mice, the progressive acute inflammatory process followed a sequence linked to factors such as size of larvae and presence of secretory-excretory products. Both infested mice and those implanted experimentally with D. hominis larvae were shown to be suitable models for the study of the parasite-host relationship in this important zoonotic myiasis.

  18. [A comparative study of three methods in detecting Angiostrongylus cantonensis larvae in lung tissue of Pomacea canaliculata].

    Science.gov (United States)

    Liu, He-Xiang; Zhang, Yi; Lv, Shan; Zhu, Dan; Ang, Xian-Hong; Hu, Ling; Zhou, Xiao-Nong

    2007-02-28

    To compare the efficiency of three methods, lung-microscopy, tissue homogenate and enzyme digestion in the detection of Angiostrongylus cantonensis larvae from the lungs of snails. 60 Pomacea canalicular infected by the first-stage larvae of A. cantonensis were divided into 2 groups and the lung of each snail from the two groups was separated from the soft body. All the lungs were examined under microscope and larval nodes were counted. Each lung from one group was ground and that from the other was artificially digested by enzyme, the number of larvae in each lung was recorded. The efficiency of three methods was compared. Enzyme digestion was also used to estimate number of larvae in lung and in other body parts. By using enzyme digestion as the standard method, the detection rate of lung-microscopy, tissue homogenate and enzyme digestion was 96.7%, 93.4% and 100% respectively (chi2=2.069, P>0.05), while the lung-microscopy was significantly faster (Z=4.782, P<0.01). The number of larvae in snail lung was positively correlated with that in other part (r=0.847, P<0.01). The lung-microscopy in larvae detection is similarly efficient to the other two methods but faster, which is therefore more suitable for snail screening in the field.

  19. Seletividade de inseticidas utilizados em cultura cafeeira para larvas de Cryptolaemus montrouzieri Mulsant Selectivity of insecticides used in the coffee crop to larvae of Cryptolaemus montrouzieri Mulsant

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Dias Rocha

    2011-06-01

    Full Text Available Assim como a maioria dos cultivos, em cafeeiro, a associação de inimigos naturais com produtos fitossanitários seletivos é uma importante estratégia no manejo integrado de pragas (MIP. Dessa forma, este estudo objetivou avaliar a seletividade de agrotóxicos utilizados na cultura cafeeira sobre larvas de Cryptolaemus montrouzieri Mulsant, 1853 (Coleoptera: Coccinellidae, em laboratório. Os bioensaios foram realizados em condições controladas (25±2°C, UR de 70±10% e fotofase de 12 horas. Cada bioensaio consistiu em seis tratamentos e dez repetições, sendo cada parcela composta por duas larvas. Para as comparações das médias dos tratamentos, empregou-se um esquema fatorial inteiramente ao acaso de produtos x número de instares para os diferentes instares subsequentes à aplicação. Os inseticidas utilizados e suas respectivas dosagens de aplicação, em g de i.a. L-1 foram: tiametoxam (0,5, imidacloprido (0,7, óleo mineral (13,3, endossulfam (2,63 e dimetoato (0,48. A testemunha foi composta apenas por água destilada. A aplicação dos produtos foi realizada por meio de torre de Potter. Avaliaram-se a sobrevivência dos espécimes após serem contaminados com os produtos e os efeitos dos compostos sobre os parâmetros reprodutivos do predador. Tiametoxam (0,5, imidacloprido (0,7 e endossulfam (2,63 foram os mais prejudiciais, tendo sido observados, para os dois primeiros, 100% de mortalidade de larvas de primeiro e de segundo instares um dia após a aplicação e significativa redução na sobrevivência das larvas de terceiro e quarto instares. Dimetoato (0,48 foi nocivo para larvas de primeiro instar e levemente nocivo para larvas de quarto instar. Em função da seletividade apresentada pelo óleo mineral (13,3, este pode ser recomendado em compatibilização com o predador C. montrouzieri em programas de MIP na cultura cafeeira, sem prejuízo ao desempenho do inimigo natural.As well as most of the crops, in coffee crop, the

  20. Stage design

    International Nuclear Information System (INIS)

    Shacter, J.

    1975-01-01

    A method is described of cycling gases through a plurality of diffusion stages comprising the steps of admitting the diffused gases from a first diffusion stage into an axial compressor, simultaneously admitting the undiffused gases from a second diffusion stage into an intermediate pressure zone of said compressor corresponding in pressure to the pressure of said undiffused gases, and then admitting the resulting compressed mixture of diffused and undiffused gases into a third diffusion stage

  1. Comparison of human papillomavirus type 16 L1 chimeric virus-like particles versus L1/L2 chimeric virus-like particles in tumor prevention.

    Science.gov (United States)

    Wakabayashi, Mark T; Da Silva, Diane M; Potkul, Ronald K; Kast, W Martin

    2002-01-01

    Chimeric human papillomavirus (HPV) virus-like particles (cVLPs) with the HPV16 E7 antigen fused to either the major capsid protein, L1, or the minor capsid protein, L2, have been used independently to protect against the formation of HPV-induced tumors in animal models. However, the advantages and disadvantages of both types of particles with respect to production and vaccine efficacy have never been analyzed. Therefore, in this study, we compared cVLPs with the HPV16 E7 antigen fused to L1 versus cVLPs with E7 fused to L2 with respect to their ability to protect mice from tumor challenge. The first 57 amino acids of E7 were used to overcome the size limitation and limited VLP production imposed by inserting polypeptides into L1 cVLPs. C57BL/6 mice were immunized with the above cVLPs at various doses. Tumor challenge was then performed with HPV16 E7-positive TC-1 cells. HPV16 L1-E7((1-57)) was superior to HPV16 L1/L2-E7((1-57)) in eliciting tumor protection at equivalent doses, although both types of particles were able to protect mice. Both cVLPs induced a specific cytotoxic T lymphocyte (CTL) response to the H2-D(b)-restricted E7 peptide (E7(49-57)) as determined by an ELISPOT assay and tetramer staining; however, immunization with the L1-E7((1-57)) cVLPs resulted in twofold higher CTL precursor frequencies. Our results demonstrate that cVLPs with the antigen fused to L1 are a more efficient vaccine with respect to tumor prevention than cVLPs with the antigen fused to L2. At the same time, however, L1 cVLPs are limited by the size of the antigen that can be incorporated and in the amount of cVLP that can be obtained from cultures when compared to L1/L2 cVLPs. This balances out their superior ability to induce protective immunity. Copyright 2002 S. Karger AG, Basel

  2. A systems biology approach to the characterization of stress response in Dermacentor reticulatus tick unfed larvae.

    Directory of Open Access Journals (Sweden)

    Margarita Villar

    Full Text Available BACKGROUND: Dermacentor reticulatus (Fabricius, 1794 is distributed in Europe and Asia where it infests and transmits disease-causing pathogens to humans, pets and other domestic and wild animals. However, despite its role as a vector of emerging or re-emerging diseases, very little information is available on the genome, transcriptome and proteome of D. reticulatus. Tick larvae are the first developmental stage to infest hosts, acquire infection and transmit pathogens that are transovarially transmitted and are exposed to extremely stressing conditions. In this study, we used a systems biology approach to get an insight into the mechanisms active in D. reticulatus unfed larvae, with special emphasis on stress response. PRINCIPAL FINDINGS: The results support the use of paired end RNA sequencing and proteomics informed by transcriptomics (PIT for the analysis of transcriptomics and proteomics data, particularly for organisms such as D. reticulatus with little sequence information available. The results showed that metabolic and cellular processes involved in protein synthesis were the most active in D. reticulatus unfed larvae, suggesting that ticks are very active during this life stage. The stress response was activated in D. reticulatus unfed larvae and a Rickettsia sp. similar to R. raoultii was identified in these ticks. SIGNIFICANCE: The activation of stress responses in D. reticulatus unfed larvae likely counteracts the negative effect of temperature and other stress conditions such as Rickettsia infection and favors tick adaptation to environmental conditions to increase tick survival. These results show mechanisms that have evolved in D. reticulatus ticks to survive under stress conditions and suggest that these mechanisms are conserved across hard tick species. Targeting some of these proteins by vaccination may increase tick susceptibility to natural stress conditions, which in turn reduce tick survival and reproduction, thus reducing

  3. Perkembangan dan Kandungan Nutrisi Larva Hermetia illucens (Linnaeus (Diptera: Stratiomyidae pada Bungkil Kelapa Sawit

    Directory of Open Access Journals (Sweden)

    RACHMAWATI RACHMAWATI

    2015-09-01

    Full Text Available Hermetia illucens, is used as a reducing agent of palm kernel meal (PKM, as well as one of alternative protein sources for aquaculture purposes. Information about biology of H. illucens is absolutely required in mass production. The objectives of these researches were to study the development of H. illucens including the effect of supplementary food to the adult, and nutrient content of the immature stage. The sample of 20 larvae from each 3 replicates were measured and weighed on 0-19th day (larva and 24th day (pupa from egg hatching. H. illucens adults were fed by water and honey 5% (v/v. Eggs were collected and counted. Nutrient content of immature stage: 5, 10, 15, 20 days old (larvae, and 25 days old (prepupae reared on PKM were analyzed proximately. Dry matter was determined by weight loss on drying at 105 oC during overnight. Crude protein was determined by Kjeldahl procedure (N x 6.25, crude fat by soxhlet (ether extract, crude ash by determining the residue after heating at 550 oC for 4–5 h. Data were analyzed descriptively by average from triplicate. The development of H. illucens was shorter than those in previous studies as the differences of abiotical factor. PKM was a suitable medium for development. It was better, however, to fed the adult with honey since it could enhance the fecundity. The young larva certainly contained the best quality of nutrition. To meet the quantity of mass production, however, the use of the elder larva (bigger was suggested.

  4. Black flies (Diptera : Simuliidae attracted to humans and water buffalos and natural infections with filarial larvae, probably Onchocerca sp., in northern Thailand

    Directory of Open Access Journals (Sweden)

    Takaoka H.

    2003-03-01

    Full Text Available Several Simulium species were investigated as to their biting habits and natural infections with filarial larvae at Ban Pan Fan, Chiang Mai Province, in northern Thailand. Female adults flies landing on or flighting around a human and a water buffalo were collected during the daytime from 06.00 to 19.00 hours on 22 June 2001. As a result, 217 S. nodosum, 86 S. asakoae and two S. nigrogilvum were obtained from a human attractant, and 416 S. nodosum, 25 S. nakhonense, 16 S. asakoae, four 5. fenestratum and two S. nigrogilvum, from a water buffalo. The blood-feeding was confirmed only for S. nodosum and S. nigrogilvum on humans, and for S. nodosum and S. nakhonense on water buffalos. Dissections of these simuliids showed that S. nodosum was naturally infected with developing filarial larvae. Two types of microfilariae were distinguished but only one type of infective larvae. These larvae resembled Onchocerca suzukii, a parasite from a wild Japanese bovid, suggesting that an unknown Onchocerca species from ruminants was transmitted in Thailand. Infection rates with all stages of larvae and third-stage larvae were 2.3 % (14/608 and 1 .0 % (6/608, respectively. This is the first report of natural infections of black flies with Onchocerca larvae in Southeast Asia, and the involved black fly species is shown to be not only anthropophilic but also zoophilic in this region.

  5. The lethal giant larvae Gene in Tribolium castaneum: Molecular Properties and Roles in Larval and Pupal Development as Revealed by RNA Interference

    Directory of Open Access Journals (Sweden)

    Da Xiao

    2014-04-01

    Full Text Available We identified and characterized the TcLgl gene putatively encoding lethal giant larvae (Lgl protein from the red flour beetle (Tribolium castaneum. Analyses of developmental stage and tissue-specific expression patterns revealed that TcLgl was constitutively expressed. To examine the role of TcLgl in insect development, RNA interference was performed in early (1-day larvae, late (20-day larvae, and early (1-day pupae. The early larvae injected with double-stranded RNA of TcLgl (dsTcLgl at 100, 200, and 400 ng/larva failed to pupate, and 100% mortality was achieved within 20 days after the injection or before the pupation. The late larvae injected with dsTcLgl at these doses reduced the pupation rates to only 50.3%, 36.0%, and 18.2%, respectively. The un-pupated larvae gradually died after one week, and visually unaffected pupae failed to emerge into adults and died during the pupal stage. Similarly, when early pupae were injected with dsTcLgl at these doses, the normal eclosion rates were reduced to only 22.5%, 18.0%, and 11.2%, respectively, on day 7 after the injection, and all the adults with abnormal eclosion died in two days after the eclosion. These results indicate that TcLgl plays an essential role in insect development, especially during their metamorphosis.

  6. The Effects of Temperature and Innate Immunity on Transmission of Campylobacter jejuni (Campylobacterales: Campylobacteraceae) Between Life Stages of Musca domestica (Diptera: Muscidae)

    DEFF Research Database (Denmark)

    Bahrndorff, Simon; Gill, C.; Lowenberger, C.

    2014-01-01

    jejuni (Jones) could be transferred between life stages of M. domestica (larvae-pupae-adults) and determined bacterial counts of C. jejuni at different time points after bacterial exposure. C. jejuni was transmitted from infected larvae to pupae, but not to the adult stage. Infected larvae maintained....../g), and these numbers dropped to 4.8 +/- 0.1 SE log(10) (CFU/g) 24 h after pupation. The decline in C. jejuni numbers during pupal development coincided with increased expression of antimicrobial peptides, including cecropin, diptericin, attacin, and defensin, in the larva-pupa transition stage and a later second peak...

  7. The Expression and Biological Significance of PD-L1 on Lung Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Cheng CHEN

    2009-08-01

    Full Text Available Background and objective Tumor-associated PD-L1 expression was recently shown to promote T-cell apoptosis and proposed as a potential mechanism of immune evasion by tumors. On the basis of the ability of tumor-associated PD-L1 to mediate activated T-cell death, it is likely that manipulation of the PD-L1 pathway at defined time points during the development of the T-cell antitumor immune response can enhance the efficacy of T-cell-based immunotherapy. Here, the levels of expression of PD-L1 on lung cancer cell lines and its role in interaction of CTL and target cells was investigated. Methods Human PBMC derived DCs were loaded with apoptotic tumor cells and stimulated by CD40 mAb (5C11. Tumor specific CTL was generated in vitro by autologous T cells co-cultured with mature DCs. Expression of PD-L1 on lung cancer cell lines H1299 and A549 were analyzed by FCM. JAM assay was used to detect the cytolytic activity of CTL with or without blocking PD-L1 by PD-L1 mAb respectively. The concentrations of IFN-γ in supernatants from distinct groups were analyzed by ELISA. Results Tumor cells-loaded mature DCs could induce the generation of the tumor specific CTL. Expression of PD-L1 was low on A549 cell, but high on H1299 cell. Blockade of PD-L1 on A549 could not improve cytolytic effect of CTL on target cells and IFN-γ production, but fragmentation of H1299 cells and IFN-γ production were significantly enhanced by the combination of PD-L1 mAb and CTL. Conclusion Expression of PD-L1 on lung cancer cell line can decrease the cytolytic effect of CTL on target cells.

  8. PRELIMINARY ESTIMATION ON POINTING ACCURACY OF JAPANESE QUASI-ZENITH SATELLITE-1 (MICHIBIKI L1-SAIF

    Directory of Open Access Journals (Sweden)

    M. Tokunaga

    2012-07-01

    Full Text Available Japanese Quasi-Zenith Satellite-1 (QZS1 named MICHIBIKI was launched in September, 2010. This paper shows a preliminary estimation of positioning accuracy of the QZS1. The mission of QZS1 is to raise the positioning accuracy of GPS. The QZS1 has 3 positioning signals named LEX, L1-SAIF and L1-CA. LEX and L1-SAIF are auxiliary signals based RTK and differential measurement using revised information derived from the electronic reference points managed by the Geographic Survey Institute of Japan respectively. QZS1 L1-SAIF signal is expected the accuracy less than 1 m. In order to estimate the positioning accuracy of QZS1 L1-SAIF, the positioning accuracy of QZS1 were compared with the accuracy of GPS single measurement. As the results, for an example, GPS accuracy is 3.17 m in latitude and 3.90 m in longitude, and L1-SAIF accuracy is 1.68 m and 1.80 m respectively. This result indicates L1-SAIF provides high accuracy than GPS. But others result showed, GPS accuracy is 1.57 m in latitude and 1.26 m in longitude and L1-SAIF accuracy is 4.03 m and 0.92 m respectively. Conclusions are; (1 L1-SAIF signal were obtain submeter accuracy. (2 Almost L1-SAIF signal were obtained high accuracy better than GPS. (3 In worst case, L1-SAIF signal were obtained worse accuracy than GPS. The reason is assumed the influence of the East Japan tremendous earthquake. As the electronic reference points were moved by the earthquake, the reinforcement value derived from the electronic reference points might be incorrect.

  9. The Specificity and Flexibility of L1 Reverse Transcription Priming at Imperfect T-Tracts

    Science.gov (United States)

    Viollet, Sébastien; Mir, Ashfaq Ali; Gabus, Caroline; Darlix, Jean-Luc; Cristofari, Gaël

    2013-01-01

    L1 retrotransposons have a prominent role in reshaping mammalian genomes. To replicate, the L1 ribonucleoprotein particle (RNP) first uses its endonuclease (EN) to nick the genomic DNA. The newly generated DNA end is subsequently used as a primer to initiate reverse transcription within the L1 RNA poly(A) tail, a process known as target-primed reverse transcription (TPRT). Prior studies demonstrated that most L1 insertions occur into sequences related to the L1 EN consensus sequence (degenerate 5′-TTTT/A-3′ sites) and frequently preceded by imperfect T-tracts. However, it is currently unclear whether—and to which degree—the liberated 3′-hydroxyl extremity on the genomic DNA needs to be accessible and complementary to the poly(A) tail of the L1 RNA for efficient priming of reverse transcription. Here, we employed a direct assay for the initiation of L1 reverse transcription to define the molecular rules that guide this process. First, efficient priming is detected with as few as 4 matching nucleotides at the primer 3′ end. Second, L1 RNP can tolerate terminal mismatches if they are compensated within the 10 last bases of the primer by an increased number of matching nucleotides. All terminal mismatches are not equally detrimental to DNA extension, a C being extended at higher levels than an A or a G. Third, efficient priming in the context of duplex DNA requires a 3′ overhang. This suggests the possible existence of additional DNA processing steps, which generate a single-stranded 3′ end to allow L1 reverse transcription. Based on these data we propose that the specificity of L1 reverse transcription initiation contributes, together with the specificity of the initial EN cleavage, to the distribution of new L1 insertions within the human genome. PMID:23675310

  10. GPR37L1 modulates seizure susceptibility: Evidence from mouse studies and analyses of a human GPR37L1 variant.

    Science.gov (United States)

    Giddens, Michelle M; Wong, Jennifer C; Schroeder, Jason P; Farrow, Emily G; Smith, Brilee M; Owino, Sharon; Soden, Sarah E; Meyer, Rebecca C; Saunders, Carol; LePichon, J B; Weinshenker, David; Escayg, Andrew; Hall, Randy A

    2017-10-01

    Progressive myoclonus epilepsies (PMEs) are disorders characterized by myoclonic and generalized seizures with progressive neurological deterioration. While several genetic causes for PMEs have been identified, the underlying causes remain unknown for a substantial portion of cases. Here we describe several affected individuals from a large, consanguineous family presenting with a novel PME in which symptoms begin in adolescence and result in death by early adulthood. Whole exome analyses revealed that affected individuals have a homozygous variant in GPR37L1 (c.1047G>T [Lys349Asn]), an orphan G protein-coupled receptor (GPCR) expressed predominantly in the brain. In vitro studies demonstrated that the K349N substitution in Gpr37L1 did not grossly alter receptor expression, surface trafficking or constitutive signaling in transfected cells. However, in vivo studies revealed that a complete loss of Gpr37L1 function in mice results in increased seizure susceptibility. Mice lacking the related receptor Gpr37 also exhibited an increase in seizure susceptibility, while genetic deletion of both receptors resulted in an even more dramatic increase in vulnerability to seizures. These findings provide evidence linking GPR37L1 and GPR37 to seizure etiology and demonstrate an association between a GPR37L1 variant and a novel progressive myoclonus epilepsy. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Análise da dieta das larvas de 4º estádio de Cricotopus sp. (Diptera: Chironomidae, em diferentes substratos artificiais e fases hídricas, no trecho superior do rio Paraná - DOI: 10.4025/actascibiolsci.v31i4.3522 Diet analysis of Cricotopus sp. larvae (Diptera: Chironomidae, fourth stage, in different artificial substrates and hydrological phases, in the upper Paraná river - DOI: 10.4025/actascibiolsci.v31i4.3522

    Directory of Open Access Journals (Sweden)

    Alice Michiyo Takeda

    2009-08-01

    Full Text Available No Brasil, estudos sobre hábitos alimentares das larvas de Chironomidae ainda são escassos e estas informações são importantes para entender a estrutura trófica e a organização dos ecossistemas aquáticos. Neste estudo, teve-se como objetivo identificar os principais itens alimentares ingeridos por Cricotopus sp. e comparar as possíveis diferenças na dieta das larvas em diferentes substratos artificiais e fases hídricas. Foram utilizados quatro tipos de substratos artificiais: madeira em forma de X (MADX, placas de nitacetal em forma de X (NITX, PVC em forma de tubo (PVCT e metal galvanizado em forma de tubo (METT, cada um com três réplicas. As coletas foram realizadas quinzenalmente, entre os meses de agosto de 2004 e dezembro de 2005. A dieta de Cricotopus sp. foi constituída por detritos, algas e hifas de fungos. Detrito foi o principal item alimentar, com valores superiores a 50% do total consumido. Os resultados indicaram que Cricotopus sp. é uma espécie coletora e, independentemente do substrato, as larvas alimentam-se dos recursos disponíveis no ambiente. Entretanto, mudanças no regime hidrológico do rio Paraná podem influenciar a disponibilidade de alimento, principalmente algumas diatomaceas como Melosira sp., consumidas em maior quantidade apenas na fase de águas baixasIn Brazil, studies on the diet of Chironomidae larvae are still scarce and these data are important to understand the trophic structure and organization of aquatic ecosystems. In this study, we identified the main food items consumed by Cricotopus sp. and compared possible differences in the larval diet at different artificial substrates and hydrological phases. We used four types of artificial substrates: X-shaped wood (MADX; X-shaped nitacetal plates (NITX; tube-shaped PVC (PVCT and tube-shaped galvanized metal (METT, each with three replicates. Samplings were undertaken fortnightly, between August 2004 and December 2005. Cricotopus sp. diet was

  12. Neuromuscular development in Novocrania anomala: evidence for the presence of serotonin and a spiralian-like apical organ in lecithotrophic brachiopod larvae

    DEFF Research Database (Denmark)

    Altenburger, Andreas; Wanninger, Andreas Wilhelm Georg

    2010-01-01

    in the craniiform (inarticulate) brachiopod Novocrania anomala. Larvae of this species are lecithotrophic and have a bilobed body with three pairs of dorsal setal bundles that emerge from the posterior lobe. Fully developed larvae exhibit a network of setae pouch muscles as well as medioventral longitudinal...... stages. In the juveniles, the nervous system stained by a-tubulin is characterized by two ventral neurite bundles with three commissures. Our data are the first direct proof for the presence of an immunoreactive neurotransmitter in lecithotrophic brachiopod larvae and demonstrate the existence of flask...

  13. Mortality of Plutella xylostella larvae treated with Aspidosperma pyrifolium ethanol extracts Mortalidade de larvas de Plutella xylostella tratadas com extratos etanólicos de Aspidosperma pyrifolium

    Directory of Open Access Journals (Sweden)

    Roseane Cristina Prédes Trindade

    2008-12-01

    Full Text Available The objective of this work was to assess the effects of Aspidosperma pyrifolium ethanol extracts on cabbage moth (Plutella xylostella larvae. The ethanol extracts of the stem bark, fruits and roots of A. pyrifolium were obtained by classical phytochemical methods, and the resulting subfractions were tested on P. xylostella, using 4 and 5 mg L-1. The crude ethanol extract of the stem bark was more lethal. The alkaloid-rich aqueous subfraction derived from the stem bark extract caused 100% larval mortality at 4 mg L-1. Insecticidal activity was associated with the presence of the monoterpenoid indole alkaloids aspidofractinine, 15-demethoxypyrifoline, and N-formylaspidofractinine. These alkaloids presented excellent insecticidal properties against P. xylostella.O objetivo deste trabalho foi avaliar os efeitos dos extratos etanólicos de Aspidosperma pyrifolium sobre lagartas da traça-das-crucíferas (Plutella xylostella. Os extratos etanólicos da casca do caule, do fruto e da raiz de A. pyrifolium foram obtidos pelos métodos fitoquímicos clássicos, e as subfrações resultantes foram testadas contra P. xylostella, nas dosagens 4 e 5 mg L-1. O extrato bruto etanólico da casca do caule foi mais letal. A subfração aquosa rica em alcalóides, derivada do extrato da casca do caule, causou 100% de mortalidade larval a 4 mg L-1. A atividade inseticida foi associada à presença dos alcalóides monoterpenóides indólicos aspidofractinina, 15-demetoxipirifolina e N-formilaspidofractinin. Estes alcalóides apresentaram excelente propriedade inseticida contra P. xylostella.

  14. Efficacy of acaricides against larvae of Rhipicephalus sanguineus (Latreille, 1806 (Acari: Ixodidae and Rhipicephalus (Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae

    Directory of Open Access Journals (Sweden)

    Luciano Melo de Souza

    2017-02-01

    Full Text Available Parasitism by mites has always been of concern with regard to losses in animal production and to the transmission of etiologic agents of important diseases as well, and about 95% of the developing forms of ticks in the non-parasitic phase are in the environment. In view of the importance of controlling larval stages of ticks in the environment, this study evaluated the efficacy of acaricides in vitro against larvae of Rhipicephalus (B. microplus and R. sanguineus. Accordingly, we tested: 15% cypermethrin (T1; 25% deltamethrin (T2; combination of cypermethrin 5% + 45% dichlorvos + 25% piperonyl butoxide (T3; combination of 15% cypermethrin + 25% chlorpyrifos + 1% citronella (T4; and 12.5% amitraz (T5. In each treatment, there were nine replicates with 20 larvae each. The larvae were observed for motility at: 1, 5, 10, 20 and 30 minutes post-treatment (MPT; 1, 2, 6, 12 and 24 hours post-treatment (HPT; and 5 days post-treatment. Tests in R. (B. microplus and R. sanguineus larvae with 25% deltamethrin served as a positive control and demonstrated 100% loss of motility at 2 HPT for both tick species. R. (B. microplus larvae were most sensitive to treatments containing 15% cypermethrin or 5% cypermethrin combined with dichlorvos and piperonyl butoxide. Larvae of R. sanguineus were most sensitive to treatment with 12.5% amitraz. However, despite the differences in acaricidal effect during the observation time, 100% efficacy was obtained for all treatments against larvae of R. sanguineus and R. (B. microplus at 12 HPT, demonstrating that appropriate doses of commercial acaricides can be effective in environmental control strategies against tick larvae.

  15. Testing pollen of single and stacked insect-resistant Bt-maize on in vitro reared honey bee larvae.

    Directory of Open Access Journals (Sweden)

    Harmen P Hendriksma

    Full Text Available The ecologically and economic important honey bee (Apis mellifera is a key non-target arthropod species in environmental risk assessment (ERA of genetically modified (GM crops. Honey bee larvae are directly exposed to transgenic products by the consumption of GM pollen. But most ERA studies only consider responses of adult bees, although Bt-proteins primarily affect the larval phases of target organisms. We adopted an in vitro larvae rearing system, to assess lethal and sublethal effects of Bt-pollen consumption in a standardized eco-toxicological bioassay. The effects of pollen from two Bt-maize cultivars, one expressing a single and the other a total of three Bt-proteins, on the survival and prepupae weight of honey bee larvae were analyzed. The control treatments included pollen from three non-transgenic maize varieties and of Heliconia rostrata. Three days old larvae were fed the realistic exposure dose of 2 mg pollen within the semi-artificial diet. The larvae were monitored over 120 h, until the prepupal stage, where larvae terminate feeding and growing. Neither single nor stacked Bt-maize pollen showed an adverse effect on larval survival and the prepupal weight. In contrast, feeding of H. rostrata pollen caused significant toxic effects. The results of this study indicate that pollen of the tested Bt-varieties does not harm the development of in vitro reared A. mellifera larvae. To sustain the ecosystem service of pollination, Bt-impact on A. mellifera should always be a crucial part of regulatory biosafety assessments. We suggest that our approach of feeding GM pollen on in vitro reared honey bee larvae is well suited of becoming a standard bioassay in regulatory risk assessments schemes of GM crops.

  16. Testing pollen of single and stacked insect-resistant Bt-maize on in vitro reared honey bee larvae.

    Science.gov (United States)

    Hendriksma, Harmen P; Härtel, Stephan; Steffan-Dewenter, Ingolf

    2011-01-01

    The ecologically and economic important honey bee (Apis mellifera) is a key non-target arthropod species in environmental risk assessment (ERA) of genetically modified (GM) crops. Honey bee larvae are directly exposed to transgenic products by the consumption of GM pollen. But most ERA studies only consider responses of adult bees, although Bt-proteins primarily affect the larval phases of target organisms. We adopted an in vitro larvae rearing system, to assess lethal and sublethal effects of Bt-pollen consumption in a standardized eco-toxicological bioassay. The effects of pollen from two Bt-maize cultivars, one expressing a single and the other a total of three Bt-proteins, on the survival and prepupae weight of honey bee larvae were analyzed. The control treatments included pollen from three non-transgenic maize varieties and of Heliconia rostrata. Three days old larvae were fed the realistic exposure dose of 2 mg pollen within the semi-artificial diet. The larvae were monitored over 120 h, until the prepupal stage, where larvae terminate feeding and growing. Neither single nor stacked Bt-maize pollen showed an adverse effect on larval survival and the prepupal weight. In contrast, feeding of H. rostrata pollen caused significant toxic effects. The results of this study indicate that pollen of the tested Bt-varieties does not harm the development of in vitro reared A. mellifera larvae. To sustain the ecosystem service of pollination, Bt-impact on A. mellifera should always be a crucial part of regulatory biosafety assessments. We suggest that our approach of feeding GM pollen on in vitro reared honey bee larvae is well suited of becoming a standard bioassay in regulatory risk assessments schemes of GM crops.

  17. Effects of warming rate, acclimation temperature and ontogeny on the critical thermal maximum of temperate marine fish larvae.

    Science.gov (United States)

    Moyano, Marta; Candebat, Caroline; Ruhbaum, Yannick; Álvarez-Fernández, Santiago; Claireaux, Guy; Zambonino-Infante, José-Luis; Peck, Myron A

    2017-01-01

    Most of the thermal tolerance studies on fish have been performed on juveniles and adults, whereas limited information is available for larvae, a stage which may have a particularly narrow range in tolerable temperatures. Moreover, previous studies on thermal limits for marine and freshwater fish larvae (53 studies reviewed here) applied a wide range of methodologies (e.g. the static or dynamic method, different exposure times), making it challenging to compare across taxa. We measured the Critical Thermal Maximum (CTmax) of Atlantic herring (Clupea harengus) and European seabass (Dicentrarchus labrax) larvae using the dynamic method (ramping assay) and assessed the effect of warming rate (0.5 to 9°C h-1) and acclimation temperature. The larvae of herring had a lower CTmax (lowest and highest values among 222 individual larvae, 13.1-27.0°C) than seabass (lowest and highest values among 90 individual larvae, 24.2-34.3°C). At faster rates of warming, larval CTmax significantly increased in herring, whereas no effect was observed in seabass. Higher acclimation temperatures led to higher CTmax in herring larvae (2.7 ± 0.9°C increase) with increases more pronounced at lower warming rates. Pre-trials testing the effects of warming rate are recommended. Our results for these two temperate marine fishes suggest using a warming rate of 3-6°C h-1: CTmax is highest in trials of relatively short duration, as has been suggested for larger fish. Additionally, time-dependent thermal tolerance was observed in herring larvae, where a difference of up to 8°C was observed in the upper thermal limit between a 0.5- or 24-h exposure to temperatures >18°C. The present study constitutes a first step towards a standard protocol for measuring thermal tolerance in larval fish.

  18. Nutritional Value of Pupae Versus Larvae of Tenebrio molitor (Coleoptera: Tenebrionidae) as Food for Rearing Podisus maculiventris (Heteroptera: Pentatomidae).

    Science.gov (United States)

    Morales-Ramos, Juan A; Rojas, M Guadalupe; Shelby, Kent S; Coudron, Thomas A

    2016-04-01

    Life-table analysis yielded demographic parameter values that indicate that Tenebrio molitor (L.) pupae are potentially more suitable factitious prey to mass-produce the predator Podisus maculiventris (Say) and are more suitable prey than the larvae. P. maculiventris developed faster (23.2 vs. 25.5 d), weighed more (females 80.9 vs. 66.6 mg and males 64.7 vs. 53.7 mg), and had a higher survival rate (0.88 vs. 0.7), fecundity, and reproductive output (87.1 vs. 22.8 eggs/female) when reared on pupae compared with larvae of T. molitor. The total protein content and soluble protein content were significantly higher in pupae (60.2 and 23%, respectively) than larvae (53.1 and 14.4%, respectively). Lipid content was significantly lower in pupae (32.1%) than larvae (35.9%), and larvae had more polyunsaturated fatty acids (83.6 vs. 56.6 mg/g) and less oleic (0.1 mg/g) and steric (6.1 mg/g) acids than pupae (37.3 and 12.3 mg/g, respectively). The total sugar content was not significantly different between pupae and larvae. However, larvae had significantly more fructose than pupae, but pupae had more galactose, glucosamine, glucose, mannose, and trehalose than larvae. Differences in nutritional composition and its impact on predator demographic parameters are potential factors that make the pupal stage a better food source.

  19. Resistance test at early larval stage of blue swimming crab, Portunus pelagicus

    Directory of Open Access Journals (Sweden)

    Mhd Ikhwanuddin

    2016-02-01

    Full Text Available The early larval stage is the crucial phase in the larviculture of blue swimming crab, Portunus pelagicus. The combination of stress resistance tests have been done to determine the maximum period of starvation and dissolved oxygen, the preferable range of temperature, salinity, pH and ammonia for P. pelagicus larvae survival at early larval stages. Larvae were exposed to various treatments as mentioned above to examine larvae competency against the stressor. In starvation test, at 12 hours, more than 50 percent of larvae were observed dead. While in the dissolved oxygen test, no larvae survived more than 6 hours without aeration treatment. The optimum temperature for larvae was 30C due to high survival rate (43.18% was found in the end of experiment. There were no larvae survival at salinity level 0 ppt, 10 ppt and 50 ppt respectively. The highest larvae survival was found at 30 ppt treatment (60.51%. The suitable pH for larval rearing condition was ranged from 8.0-8.2 (survival rate were 48.60% and 70.47%, respectively owing to larval survival rate in others treatments were very low. In the last experiment, lower concentration of ammonia treatments (0.02, 0.2 ppm showed higher survival rate (58.54% and 23.90% whereas the larvae in 2 ppm and 20 ppm treatments died with 24 hours and 6 hours after spike.

  20. A key to larvae of species belonging to the genus Diamesa from Alps and Apennines (Italy

    Directory of Open Access Journals (Sweden)

    Bruno Rossaro

    2015-07-01

    Full Text Available A key to species belonging to the genus Diamesa Meigen, 1835 (Diptera, Chironomidae from the Alps and Apennines (Italy is presented using characters observable in the fourth-instar larva. The larvae are separated on the basis of qualitative and quantitative characters. At present fifteen species from the Italian Alps are described in all three life stages, but only twelve species groups can be separated as larvae. The separation is based on the length and thickness of anal setae, antennal ratio, head capsule color and few other characters of the labrum and mentum. The shape of mental and mandibular teeth is still a valid taxonomic character, but unfortunately these characters can be rarely used because teeth are often excessively worn in samples collected in the field. Quantitative characters show variability within each species, differing according to the duration of larval development and must be used with caution. The species groups which can be separated in the larval stage are: the dampfi group, which includes D. dampfi and D. permacra, the latitarsis group including D. modesta and D. latitarsis, the zernyi group including D. zernyi and D. vaillanti. The species within each of these groups at present cannot be separated. D. starmachi, D. steinboecki, D. goetghebueri, D. bertrami, D. aberrata, D. incallida, D. cinerella, D. tonsa and D. insignipes can be separated from all the other known species in larval stage.

  1. Morphology of stomatopod larvae from National Parks: Sistema Arrecifal Veracruzano and Arrecife Puerto Morelos, Mexico

    Directory of Open Access Journals (Sweden)

    Sergio Cházaro-Olvera

    2018-03-01

    Full Text Available ABSTRACT The present study provides information on the morphology of stomatopod larvae found in two different reef systems which are also considered national parks: the Sistema Arrecifal Veracruzano (SAVNP and Arrecife Puerto Morelos (APMNP. Zooplankton samples were collected at 26 stations of the SAVNP and four stations of the APMNP. Stomatopod larvae were identified and classified by their larval stage. We found representatives of three stomatopod superfamilies: the superfamily Gonodactyloidea Giesbrecht, 1910 was represented by Neogonodactylus oerstedii (Hansen, 1895, Neogonodactylus wennerae Manning and Heard, 1997, and Pseudosquillidae genus and species indeterminate; the superfamily Lysiosquilloidea Giesbrecht, 1910 was represented by Lysiosquilloidea genus and species indeterminate, Lysiosquilla sp., Lysiosquilla scabricauda (Lamarck, 1818 and Nannosquilla adkisoni Camp and Manning, 1982; the superfamily Squilloidea was represented by larvae of Alima neptuni (Linnaeus, 1768, Squilla spp., and Squilla empusa Say, 1818. We were able to identify and describe four stages of larval development for representatives of these superfamilies. This is the first study describing several stages of larval development of different species of the stomatopods from the Gulf of Mexico and Caribbean Sea.

  2. Larvae of Contracaecum sp. (Nematoda: Anisakidae) in the threatened freshwater fish Sandelia capensis (Anabantidae) in South Africa

    Czech Academy of Sciences Publication Activity Database

    Moravec, František; van Rensburg, C.J.; Van As, L. L.

    2016-01-01

    Roč. 120, č. 3 (2016), s. 251-254 ISSN 0177-5103 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : parasitic nematode * third-stage larva * paratenic host * endangered fish species * Africa Subject RIV: EG - Zoology Impact factor: 1.549, year: 2016

  3. Functional response of Chrysoperla carnea (Neuroptera: Chrysopidae) to Helicoverpa armigera (Lepidoptera: Noctuidae): effect of prey and predator stages

    DEFF Research Database (Denmark)

    Hassanpour, Mehdi; Mohaghegh, Jafar; Iranipour, Shahzad

    2011-01-01

    Understanding predator–prey interactions has a pivotal role in biological control programs. This study evaluated the functional response of three larval instars of the green lacewing, Chrysoperla carnea (Stephens), preying upon eggs and first instar larvae of the cotton bollworm, Helicoverpa...... armigera Hübner. The first and second instar larvae of C. carnea exhibited type II functional responses against both prey stages. However, the third instar larvae of C. carnea showed a type II functional response to the first instar larvae of H. armigera, but a type III functional response to the eggs....... For the first instar larvae of C. carnea, the attack rate on H. armigera eggs was significantly higher than that on the larvae, whereas the attack rate of the second instar C. carnea on H. armigera larvae was significantly higher than that on the eggs. For the third instar larvae of C. carnea, the attack rate...

  4. Larva of Palaemnema brasiliensis Machado (Odonata: Platystictidae), from Amazonas, Brazil.

    Science.gov (United States)

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-02-09

    The larva of Palaemnema brasiliensis Machado, 2009 is described and illustrated based on last-instar larvae and exuviae of reared larvae collected in a blackwater stream in Barcelos and Presidente Figueiredo municipalities, Amazonas state, Brazil. The larva of P. brasiliensis can be distinguished from the two South American species of the genus with described larvae (P. clementia Selys and P. mutans Calvert), mainly by presence of a single obtuse cusp on the labial palp, the presence and configuration of setae in the caudal lamellae, and the proportional length of terminal filaments of the caudal lamellae. The family is recorded here for the first time in Brazilian state of Amazonas.

  5. Ingestion of bacteria by cod (Gadus morhua L.) larvae. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983

    OpenAIRE

    Olafsen, Jan A.

    1984-01-01

    The uptake of Rhodamine-labelled bacteria by cod larvae was demonstrated using a fluorescent microscopy technique, which allowed a quick estimate of bacterial uptake and gut clearance. Live or heat-killed bacteria, isolated from cod-eggs, were rapidly ingested by larvae at yolk-sac and older stages. A substantial uptake could be seen after 15 min exposure, and eventually the bacteria became densely packed in the digestive tract. Some morphological details in the develo...

  6. The Implications of Cognitive Models in L1 and L2 Writing.

    Science.gov (United States)

    Railey, Kevin; And Others

    A study investigated one dimension of metacognition--the knowledge of cognition--in first language (L1) and second language (L2) writing. Subjects were 20 students (10 L1 and 10 L2) in a first level college writing course. A questionnaire elicited subjects' definitions of good writing, their notions of the constituent features of the writing…

  7. L2 Word Recognition: Influence of L1 Orthography on Multi-Syllabic Word Recognition

    Science.gov (United States)

    Hamada, Megumi

    2017-01-01

    L2 reading research suggests that L1 orthographic experience influences L2 word recognition. Nevertheless, the findings on multi-syllabic words in English are still limited despite the fact that a vast majority of words are multi-syllabic. The study investigated whether L1 orthography influences the recognition of multi-syllabic words, focusing on…

  8. Modeling the development of L1 and EFL writing proficiency of secondary school students

    NARCIS (Netherlands)

    Schoonen, R.; van Gelderen, A.; Stoel, R.D.; Hulstijn, J.; de Glopper, K.

    2011-01-01

    This longitudinal study investigates the development of writing proficiency in English as a foreign language (EFL), in contrast to the development of first language (L1) writing proficiency in Dutch L1, in a sample of almost 400 secondary school students in the Netherlands. Students performed

  9. Modeling the Development of L1 and EFL Writing Proficiency of Secondary School Students

    NARCIS (Netherlands)

    Schoonen, Rob; van Gelderen, Amos; Stoel, Reinoud D.; Hulstijn, Jan; de Glopper, Cornelis

    This longitudinal study investigates the development of writing proficiency in English as a foreign language (EFL), in contrast to the development of first language (L1) writing proficiency in Dutch L1, in a sample of almost 400 secondary school students in the Netherlands. Students performed

  10. L1 Explicit Instruction Can Improve L2 Online and Offline Performance

    Science.gov (United States)

    McManus, Kevin; Marsden, Emma

    2017-01-01

    This study investigated the effectiveness of providing L1 explicit information (EI) with practice for making more accurate and faster interpretations of L2 French "Imparfait" (IMP). Two treatments were investigated: (a) "L2-only," providing EI about the L2 with L2 interpretation practice, and (b) "L2+L1," providing…

  11. [Regulatory Mechanisms of PD-L1 Expression and Its Role in Immune Evasion].

    Science.gov (United States)

    Kataoka, Keisuke

    2017-11-01

    Immune checkpoint blockade therapy using anti-PD-1 or anti-PD-L1 antibodies can unleash anti-tumor immunity and induce durable remission in a variety ofhuman cancers. However, the regulatory mechanisms of PD-L1 expression mediating immune evasion ofcancer cells have not been fully elucidated, including the genetic alterations causing PD-L1 overexpression. Recently, we have reported a novel genetic mechanism ofimmune evasion associated with structural variations(SVs)disrupting the 3'-untranslated region(UTR)ofthe PD-L1 gene in various malignancies, such as aggressive lymphomas and gastrointestinal cancers. Despite a heterogenous nature ofthese SVs, they are closely associated with a marked upregulation of PD-L1 expression, which augments tumor growth and escape from anti-tumor immunity. Here we present an overview of the regulatory mechanisms of PD-L1 expression in cancer cells, highlighting the genetic mechanisms of PD-L1 constitutive activation, with specific focus on PD-L1 3'-UTR disruption.

  12. Multilingual Acquisition of Vowels in L1 Polish, L2 Danish and L3 English

    Science.gov (United States)

    Sypianska, Jolanta

    2016-01-01

    The aim of this paper is to determine whether all languages in the linguistic repertoire of a multilingual speaker manifest cross-linguistic influence (CLI) and establish the directions of CLI on the basis of chosen vowels from the linguistic repertoire of two groups: the Bilingual group (L1 Polish/L2 Danish) and the Multilingual group (L1

  13. Ternary Weighted Function and Beurling Ternary Banach Algebra l1ω(S

    Directory of Open Access Journals (Sweden)

    Mehdi Dehghanian

    2011-01-01

    Full Text Available Let S be a ternary semigroup. In this paper, we introduce our notation and prove some elementary properties of a ternary weight function ω on S. Also, we make ternary weighted algebra l1ω(S and show that l1ω(S is a ternary Banach algebra.

  14. L1-L2 Transfer in the Narrative Styles of Chinese EFL Learners' Written Personal Narratives

    Science.gov (United States)

    Su, I-Ru; Chou, Yi-Chun

    2016-01-01

    Most of the research on second language (L2) narratives has focused on whether or how L2 learners carry their L1 narrative styles into L2 narration; few studies have explored whether L2 learners' knowledge of the L2 also in turn affects their L1 narrative performance. The present study attempted to probe the issue of cultural transfer in narrative…

  15. L1 Differences and L2 Similarities: Teaching Verb Tenses in English

    Science.gov (United States)

    Collins, Laura

    2007-01-01

    In making decisions regarding the focus for grammar teaching, ESL instructors may take into consideration errors that appear to result from the influence of their students' first language(s) (L1). There is also evidence from language acquisition research suggesting that for some grammatical features, learners of different L1 backgrounds may face…

  16. Rate of Acquiring and Processing L2 Color Words in Relation to L1 Phonological Awareness

    Science.gov (United States)

    Hu, Chieh-Fang

    2008-01-01

    This study examined the effect of first language (L1) phonological awareness on the rate of learning new second language (L2) color terms and the rate of processing old color terms. Two groups of 37 children participated; they differed on L1 phonological awareness measured at Grade 3. At Grade 5, over multiple trials, the children learned new L2…

  17. Developmental Sequences in L1 (Normal and Impaired) and L2 Acquisition of Swedish Syntax.

    Science.gov (United States)

    Hakansson, Gisela; Nettelbladt, Ulrika

    1993-01-01

    Examined syntactic development in acquisition of Swedish as a first language in normal (L1) and specifically language-impaired (SLI) children, and acquisition of Swedish as a second language (L2). Similarity between SLI learners and L2 learners is evidence against the hypothesis that there is a fundamental L1-L2 difference. Some data are appended.…

  18. Heterologous production of human papillomavirus type-16 L1 protein by a lactic acid bacterium

    Directory of Open Access Journals (Sweden)

    Bermúdez-Humarán Luis G

    2009-08-01

    Full Text Available Abstract Background The expression of vaccine antigens in lactic acid bacteria (LAB is a safe and cost-effective alternative to traditional expression systems. In this study, we investigated i the expression of Human papillomavirus type 16 (HPV-16 L1 major capsid protein in the model LAB Lactococcus lactis and ii the ability of the resulting recombinant strain to produce either capsomer-or virus-like particles (VLPs. Results and conclusion HPV-16 L1 gene was cloned into two vectors, pCYT and pSEC, designed for controlled intra- or extracellular heterologous expression in L. lactis, respectively. The capacity of L. lactis harboring either pCYT:L1 or pSEC:L1 plasmid to accumulate L1 in the cytoplasm and supernatant samples was confirmed by Western blot assays. Electron microscopy analysis suggests that, L1 protein produced by recombinant lactococci can self-assemble into structures morphologically similar to VLPs intracellularly. The presence of conformational epitopes on the L. lactis-derived VLPs was confirmed by ELISA using an anti-HPV16 L1 capsid antigen antibody. Our results support the feasibility of using recombinant food-grade LAB, such as L. lactis, for the production of L1-based VLPs and open the possibility for the development of a new safe mucosal vector for HPV-16 prophylactic vaccination.

  19. X-linked hydrocephalus : A novel missense mutation in the L1CAM gene

    NARCIS (Netherlands)

    Sztriha, L; Vos, YJ; Verlind, E; Johansen, J; Berg, B

    2002-01-01

    X-linked hydrocephalus is associated with mutations in the L1 neuronal cell adhesion molecule gene. L1 protein plays a key role in neurite outgrowth, axonal guidance, and pathfinding during the development of the nervous system. A male is described with X-linked hydrocephalus who had multiple small

  20. Modeling of the structure of ribosomal protein L1 from the archaeon Haloarcula marismortui

    Science.gov (United States)

    Nevskaya, N. A.; Kljashtorny, V. G.; Vakhrusheva, A. V.; Garber, M. B.; Nikonov, S. V.

    2017-07-01

    The halophilic archaeon Haloarcula marismortui proliferates in the Dead Sea at extremely high salt concentrations (higher than 3 M). This is the only archaeon, for which the crystal structure of the ribosomal 50S subunit was determined. However, the structure of the functionally important side protuberance containing the abnormally negatively charged protein L1 (HmaL1) was not visualized. Attempts to crystallize HmaL1 in the isolated state or as its complex with RNA using normal salt concentrations (≤500 mM) failed. A theoretical model of HmaL1 was built based on the structural data for homologs of the protein L1 from other organisms, and this model was refined by molecular dynamics methods. Analysis of this model showed that the protein HmaL1 can undergo aggregation due to the presence of a cluster of positive charges unique for proteins L1. This cluster is located at the RNA-protein interface, which interferes with the crystallization of HmaL1 and the binding of the latter to RNA.

  1. Code-Switching: L1-Coded Mediation in a Kindergarten Foreign Language Classroom

    Science.gov (United States)

    Lin, Zheng

    2012-01-01

    This paper is based on a qualitative inquiry that investigated the role of teachers' mediation in three different modes of coding in a kindergarten foreign language classroom in China (i.e. L2-coded intralinguistic mediation, L1-coded cross-lingual mediation, and L2-and-L1-mixed mediation). Through an exploratory examination of the varying effects…

  2. Complete Genome Sequence of Bacillus velezensis L-1, Which Has Antagonistic Activity against Pear Diseases

    OpenAIRE

    Sun, Pingping; Cui, Jianchao; Jia, Xiaohui; Wang, Wenhui

    2017-01-01

    ABSTRACT Bacillus velezensis L-1 is an effective biocontrol agent against pear diseases. Here, we report the complete genome sequence of B. velezensis L-1 in which clusters related to the biosynthesis of secondary metabolites were predicted. This genome provides insights into the possible biocontrol mechanisms and furthers application of this specific bacterium.

  3. Complete Genome Sequence of Bacillus velezensis L-1, Which Has Antagonistic Activity against Pear Diseases.

    Science.gov (United States)

    Sun, Pingping; Cui, Jianchao; Jia, Xiaohui; Wang, Wenhui

    2017-11-30

    Bacillus velezensis L-1 is an effective biocontrol agent against pear diseases. Here, we report the complete genome sequence of B. velezensis L-1 in which clusters related to the biosynthesis of secondary metabolites were predicted. This genome provides insights into the possible biocontrol mechanisms and furthers application of this specific bacterium. Copyright © 2017 Sun et al.

  4. Structural basis of a novel PD-L1 nanobody for immune checkpoint blockade.

    Science.gov (United States)

    Zhang, Fei; Wei, Hudie; Wang, Xiaoxiao; Bai, Yu; Wang, Pilin; Wu, Jiawei; Jiang, Xiaoyong; Wang, Yugang; Cai, Haiyan; Xu, Ting; Zhou, Aiwu

    2017-01-01

    The use of antibodies to target immune checkpoints, particularly PD-1/PD-L1, has made a profound impact in the field of cancer immunotherapy. Here, we identified KN035, an anti-PD-L1 nanobody that can strongly induce T-cell responses and inhibit tumor growth. The crystal structures of KN035 complexed with PD-L1 and free PD-L1, solved here at 1.7 and 2.7 Å resolution, respectively, show that KN035 competes with PD-1 (programmed death protein 1) for the same flat surface on PD-L1, mainly through a single surface loop of 21 amino acids. This loop forms two short helices and develops key hydrophobic and ionic interactions with PD-L1 residues, such as Ile54, Tyr56 and Arg113, which are also involved in PD-1 binding. The detailed mutagenesis study identified the hotspot residues of the PD-L1 surface and provides an explanation for the stronger (~1 000-fold) binding of KN035 to PD-L1 than PD-1 and its lack of binding to PD-L2. Overall, this study reveals how a single immunoglobulin-variable scaffold of KN035 or PD-1 can bind to a flat protein surface through either a single surface loop or beta-sheet strands; and provides a basis for designing new immune checkpoint blockers and generating bi-specific antibodies for combination therapy.

  5. Comparing L1 and L2 Organizational Patterns in the Argumentative Writing of Japanese EFL Students.

    Science.gov (United States)

    Hirose, Keiko

    2003-01-01

    Compared Japanese first language (L1) and English second language (L2) organizational patterns in the argumentative writing of Japanese English-as-a-Foreign-Language (EFL) student writers. Made within-subject comparisons of L1 and L2 compositions in terms of organizational patterns, organizational scores, and overall quality. (Author/VWL)

  6. Exploring a New Technique for Comparing Bilinguals' L1 and L2 Reading Speed

    Science.gov (United States)

    Gauvin, Hanna S.; Hulstijn, Jan H.

    2010-01-01

    Is it possible to tell whether bilinguals are able to read simple text in their two languages equally fluently? Is it thus possible to distinguish balanced bilinguals from unbalanced bilinguals with respect to reading fluency in their first language (L1) and second language (L2)? In this study, we avoided making direct comparisons between L1 and…

  7. L1 and L2 Distance Effects in Learning L3 Dutch

    Science.gov (United States)

    Schepens, Job J.; der Slik, Frans; Hout, Roeland

    2016-01-01

    Many people speak more than two languages. How do languages acquired earlier affect the learnability of additional languages? We show that linguistic distances between speakers' first (L1) and second (L2) languages and their third (L3) language play a role. Larger distances from the L1 to the L3 and from the L2 to the L3 correlate with lower…

  8. A study of the life history of brazilian sardine, Sardinella brasiliensis.: III. development of sardine larvae

    Directory of Open Access Journals (Sweden)

    Yasunobu Matsuura

    1975-01-01

    Full Text Available Larvae and juveniles of S. brasiliensis (Steindachner, 1879, ranging from 6.4 mm to 35.5 mm, were identified from plankton samples taken in waters off the southern Brazilian coast from 1969 through 1971. Changes in the pattern of pigmentation, body proportions and formation of fin rays are described. During transformation stage a considerable advancement of the dorsal and anal fins was observed. Changes in body proportions are pronounced at the size of 19 mm. Complete ossification of all fin rays is attained at the size of 20 mm, but ossification of the ventral scutes is delayed and completed only at the size of 30 mm. Ossification of the vertebral column was completed at the size of about 16 mm.O presente trabalho é parte do projeto SOL e tem por objetivo descrever a morfologia das larvas da sardinha verdadeira, Sardinella brasiliensis (=S. aurita, com o intuito de determinar um padrão que possibilite a identificação das mesmas. São feitas considerações sobre a morfologia das larvas de outros clupeídeos existentes na região e ressaltadas as diferenças com relação as larvas de S. brasiliensis. Os resultados, posteriormente, serão usados como base para o estudo quantitativo da abundância de larvas de sardinha. O material foi coletado na costa sul do Brasil de 1969 a 1971, com uma rede de plâncton do tipo cônico-cilíndrico. Durante o desenvolvimento das larvas, foi observado um considerável deslocamento das bases das nadadeiras dorsal e anal, para uma posição mais anterior. Com o tamanho de 19 mm (comprimento padrão, ocorre uma mudança geral, considerável, nas proporções corporais. A ossificação de todos os raios das nadadeiras completa-se quando a larva atinge 20 mm, mas a ossificação dos escudos ventrais só se completa quando ela atinge 30 mm de comprimento. A ossificação das vertebras completa-se a 16 mm de comprimento. O tamanho de 19 mm foi considerado como o fim do estagio larval, e, apos este comprimento

  9. Evolution and development of the adelphophagic, intracapsular Schmidt's larva of the nemertean Lineus ruber.

    Science.gov (United States)

    Martín-Durán, José M; Vellutini, Bruno C; Hejnol, Andreas

    2015-01-01

    The life cycle of many animals includes a larval stage, which has diversified into an astonishing variety of ecological strategies. The Nemertea is a group of spiralians that exhibits a broad diversity of larval forms, including the iconic pilidium. A pelagic planktotrophic pilidium is the ancestral form in the Pilidiophora, but several lineages exhibit deviations of this condition, mostly as a transition to pelagic lecithotrophy. The most extreme case occurs, however, in the Pilidiophoran Lineus ruber, which exhibits an adelphophagic intracapsular pilidium, the so-called Schmidt's larva. We combined confocal laser scanning microscopy and gene expression studies to characterize the development and metamorphosis of the Schmidt's larva of L. ruber. The larva forms after gastrulation, and comprises a thin epidermis, a proboscis rudiment and two pairs of imaginal discs from which the juvenile will develop. The cells internalized during gastrulation form a blind gut and the blastopore gives rise to the mouth of the larva and juvenile. The Schmidt's larva eats other siblings that occupy the same egg capsule, accumulating nutrients for the juvenile. A gradual metamorphosis involves the differentiation of the juvenile cell types from the imaginal discs and the shedding of the larval epidermis. The expression of evolutionarily conserved anterior (foxQ2, six3/6, gsc, otx), endomesodermal (foxA, GATA456-a, twi-a) and posterior (evx, cdx) markers demonstrate that the juvenile retains the molecular patterning of the Schmidt's larva. After metamorphosis, the juveniles stay over 20 days within the egg masses, until they are fully mature and hatch. The evolution of the intracapsular Schmidt's larva involved the loss of the typical feeding structures of the planktotrophic pilidium and a precocious formation of the imaginal discs, as also observed in other pelagic lecithotrophic forms. However, no special adaptations are observed related to adelphophagy. As in planktotrophic

  10. PENGARUH HORMON ECDYSON TERHADAP SINTASAN DAN PERIODE MOULTING PADA LARVA KEPITING BAKAU Scylla olivacea

    Directory of Open Access Journals (Sweden)

    Sutia Budi

    2018-01-01

    Full Text Available Kepiting Bakau Scylla olivacea merupakan salah satu komoditas perikanan yang memiliki nilai ekonomis yang sangat tinggi. Kendala yang dihadapi dalam kegiatan perbenihan kepiting bakau adalah masih tingginya tingkat mortalitas. Tujuan penelitan untuk mengevaluasi pengaruh hormon ecdyson terhadap sintasan dan periode moulting pada larva kepiting bakau Scylla olivacea. Penelitian dilakukan di Unit Stasiun Pembenihan Kepiting Maranak Balai Riset Perikanan Budidaya Air Payau dan Penyuluhan Perikanan (BRPBAP3 Maros, Provinsi Sulawesi Selatan. Hewan uji berupa larva kepiting bakau Scylla spp. stadia zoea. Pakan uji dalam penelitian berupa rotifer dan Artemia yang dilakukan pengkayaan dengan hormon ecdyson. Wadah penelitian berupa akuarium 110 L berjumlah 12 buah yang diisi dengan air sebanyak 100 L, air bersalinitas 28-30 ppt dengan kepadatan larva sebanyak 50 ekor/L. Perlakuan yang diuji adalah berbagai dosis hormon ecdyson dalam pakan, yakni A= 0 mg/L; B= 0,5 mg/L; C= 1 mg/L; dan D= 1,5 mg/L; dengan tiga kali ulangan. Parameter yang diukur adalah sintasan dan periode moulting. Hasil penelitian menunjukkan bahwa perlakuan dosis hormon ecdyson memberikan pengaruh yang baik terhadap sintasan dan periode moulting larva kepiting bakau. Mud crab, Scylla olivacea is one of highly valued and sought-after fishery commodities. Despite its high economic value, mud crab culture still faces a problem in producing high-quality seed which is high mortality rate post-spawning. The study aim was to evaluate the effect of the Ecdyson hormone on the survival rate and molting period of the mud crab larvae. The study was conducted at the Maranak Crab Seedling, BRPBAP3 Maros, South Sulawesi Province. The trial used mud crabs larvae that were in zoea stage. The trial feed was given in the form of Rotifer and Artemia enriched with the Ecdyson hormone. Twelve 110-liter aquaria were filled with 100 L of 28-30 ppt of seawater. The stocking density of mud crab seed was 50

  11. Membranous and Cytoplasmic Expression of PD-L1 in Ovarian Cancer Cells.

    Science.gov (United States)

    Qu, Qiu-Xia; Xie, Fang; Huang, Qin; Zhang, Xue-Guang

    2017-01-01

    Expression of programmed death-ligand 1 (PD-L1) on tumor cells represents a powerful immune evasion pathway, but the role of intracellular or cytoplasmic PD-L1 has not been investigated in ovarian cancer cells. Flow cytometry (FCM), Real-time PCR (qPCR), immunohistochemistry (IHC) and western blot were used to determine the expression of PD-L1 in ovarian cancer cells. The cytokines detected in the tumor or tumor associated macrophage (TAM) were used to treat cancer cells. PD-L1 blockade and silencing were used to elucidate the functional significance of cancer-related PD-L1 expression. Based on the results presented, PD-L1 was found variably expressed in the cytoplasm and the cell surface of both HO8910 and SKOV3 cells. TAM or IFN-γ, TNF-α, IL-10 and IL-6 released from TAM stimulated the expression of PD-L1 at the surface of the cancer cells. The IHC results were consistent with the data in vitro showing infiltration of TAM correlated with membranous PD-L1. The increases of PD-L1 at the surface were not due to a shift in the proportion of surface versus intracellular protein, but the contribution of extracellular signal-regulated kinase (ERK)1/2 and phosphoinositide 3-kinase (PI3K) pathway activation. As a consequence, inducible membranous PD-L1 expression on SKOV3 inhibited CD8+ T cell function, and cytoplasmic PD-L1 promoted cancer cell growth. Additionally, in mouse models, both PD-L1 and PD-1 mAb resulted in tumor growth inhibition and demonstrated a potential to decrease the number of PD-1+CD8+T cells. We conclude that TAM induced PD-L1 on the cancer cells represents an immune evasion mechanism. The observations confirm the therapeutic potential of PD-L1/PD-1 mAb to reactivate anti-tumor immunity in ovarian cancer. © 2017 The Author(s). Published by S. Karger AG, Basel.

  12. Exonization of active mouse L1s: a driver of transcriptome evolution?

    Directory of Open Access Journals (Sweden)

    Badge Richard

    2007-10-01

    Full Text Available Abstract Background Long interspersed nuclear elements (LINE-1s, L1s have been recently implicated in the regulation of mammalian transcriptomes. Results Here, we show that members of the three active mouse L1 subfamilies (A, GF and TF contain, in addition to those on their sense strands, conserved functional splice sites on their antisense strands, which trigger multiple exonization events. The latter is particularly intriguing in the light of the strong antisense orientation bias of intronic L1s, implying that the toleration of antisense insertions results in an increased potential for exonization. Conclusion In a genome-wide analysis, we have uncovered evidence suggesting that the mobility of the large number of retrotransposition-competent mouse L1s (~2400 potentially active L1s in NCBIm35 has significant potential to shape the mouse transcriptome by continuously generating insertions into transcriptional units.

  13. Improved sparse reconstruction for fluorescence molecular tomography with L1/2 regularization.

    Science.gov (United States)

    Guo, Hongbo; Yu, Jingjing; He, Xiaowei; Hou, Yuqing; Dong, Fang; Zhang, Shuling

    2015-05-01

    Fluorescence molecular tomography (FMT) is a promising imaging technique that allows in vivo visualization of molecular-level events associated with disease progression and treatment response. Accurate and efficient 3D reconstruction algorithms will facilitate the wide-use of FMT in preclinical research. Here, we utilize L1/2-norm regularization for improving FMT reconstruction. To efficiently solve the nonconvex L1/2-norm penalized problem, we transform it into a weighted L1-norm minimization problem and employ a homotopy-based iterative reweighting algorithm to recover small fluorescent targets. Both simulations on heterogeneous mouse model and in vivo experiments demonstrated that the proposed L1/2-norm method outperformed the comparative L1-norm reconstruction methods in terms of location accuracy, spatial resolution and quantitation of fluorescent yield. Furthermore, simulation analysis showed the robustness of the proposed method, under different levels of measurement noise and number of excitation sources.

  14. Status Kerentanan Larva Aedes aegypti terhadap Temefos (Organofosfat di Tiga Kabupaten/Kota Provinsi Aceh

    Directory of Open Access Journals (Sweden)

    Mara Ipa

    2017-12-01

    Full Text Available Abstract. Dengue haemorrhagic fever (DHF incidence rate in Aceh Province for the past three years 2012-2014 were fluctuated from 51‰, 29 ‰ and 45 ‰. The most widely used larvacide to control larvae Ae. aegypti is temefos, in Indonesia 1% temefos (abate 1SG started used in 1976, and since 1980 has been used for the eradication program of Ae. aegypti larvae. The intensive use of temefos will be not a problem until population were dominated by resistant individuals. The purpose of this study was to determine the status of susceptibility of Ae. aegypti larvae against temefos in three dengue fever endemic areas in Aceh. We conducted an observational study to examine the susceptibility of Ae. aegypti population in 3 districts of Aceh Province: Banda Aceh, Lhokseumawe and Aceh Besar. Entomological survey and larval collection was assigned. Larvae then reared in laboratory until third generation. Third and early fourth instars stage of Ae. aegypti larvae were used as test samples. Susceptibility test was undergo based on World Health Organization guidelines. Results shows that larva Ae. aegypti from Banda Aceh (100% and Lhokseumawe (99% districts was still susceptible, while Aceh Besar (97% indicates tolerance to temefos 0,02%. In conclusion, temefos still effective to be used as larvicide for vector control in those three endemic of dengue fever in Aceh Province. The priority vector control program that can be suggested is put mosquito breeding place eradication called PSN as a proactive movement in community.Keywords: Aedes aegypti, temefos, susceptibility, insecticide, AcehAbstrak. Angka insidensi demam berdarah dengue (DBD di Provinsi Aceh tahun 2012-2014 berturut turut 51‰ menurun 29 ‰ dan meningkat kembali 45 ‰. Penggunaan larvasida temefos 1% (abate ISG untuk mengendalikan larva Aedes aegypti sudah digunakan oleh program sejak 1976. Penggunaan larvasida tidak akan menjadi masalah sampai suatu populasi didominasi oleh individu

  15. Clinicopathologic implications of CD8+/Foxp3+ ratio and miR-574-3p/PD-L1 axis in spinal chordoma patients.

    Science.gov (United States)

    Zou, Ming-Xiang; Guo, Ke-Miao; Lv, Guo-Hua; Huang, Wei; Li, Jing; Wang, Xiao-Bin; Jiang, Yi; She, Xiao-Ling

    2018-02-01

    Currently, little is known about the interactions between microRNAs (miRNAs) and the PD-1/PD-L1 signaling pathway in chordoma, and data discussing the role of the immune milieu in chordoma prognosis are limited. We aimed to analyze the relationship between PD-L1, miR-574-3p, microenvironmental tumor-infiltrating lymphocytes (TILs) and clinicopathological features of spinal chordoma patients. PD-L1 expression and TILs (including Foxp3 + , CD8 + , PD-1 + and PD-L1 + ) were assessed by immunohistochemistry in tumor specimens of 54 spinal chordoma patients. MiRNAs microarray and bioinformatical analysis were used to identify miRNAs potentially regulating PD-L1 expression, which were further validated by quantitative RT-PCR. miR-574-3p was identified to potentially regulate PD-L1 expression in chordoma, which inversely correlated with PD-L1. Positive PD-L1 expression on tumor cells was associated with advanced stages (P = 0.041) and TILs infiltration (P = 0.005), whereas decreased miR-574-3p level correlated with higher muscle invasion (P = 0.012), more severe tumor necrosis (P = 0.022) and poor patient survival. Importantly, a patient subgroup with PD-L1 + /miR-574-3p low chordoma phenotype was significantly associated with worse local recurrence-free survival (LRFS) (P = 0.026). PD-1 + TILs density was associated with surrounding muscle invasion (P = 0.014), and independently portended poor LRFS (P = 0.040), while PD-L1 + TILs showed tendencies of less aggressive clinical outcomes. Multivariate analysis of OS only found CD8 + /Foxp3 + ratio to be independent prognostic factor (P = 0.022). These findings may be useful to stratify patients into prognostic groups and provide a rationale for the use of checkpoint blockade therapy, possibly by administering miR-574-3p mimics, in spinal chordoma.

  16. Analysis of feeding behavior of Drosophila larvae on liquid food.

    Science.gov (United States)

    Shen, Ping

    2012-05-01

    The food responses of Drosophila larvae offer an excellent opportunity to study the genetic and neural regulation of feeding behavior. Compared with fed larvae, hungry larvae are more likely to display aggressive foraging, rapid food intake, compensatory feeding, and stress-resistant food procurement. Behavioral assays have been developed to quantitatively assess particular aspects of the hunger-driven food response. In combination, these assays help define the specific role of signaling molecules or neurons in the regulation of feeding behavior in foraging larvae. This protocol describes the analysis of larvae feeding on liquid food. The test is designed for quantitative assessment of the food ingestion rate of individual larvae under different energy states. It provides a simple and reliable way to measure the graded modification of the baseline feeding rate of larvae as food deprivation is prolonged. The test is applicable to routine functional testing and larger-scale screening of genetic mutations and biologics that might affect food consumption.

  17. Velcro-Like System Used to Fix a Protective Faecal Shield on Weevil Larvae

    Science.gov (United States)

    Stejskal, Robert; Trnka, Filip; di Giulio, Andrea

    2017-01-01

    The last instar larva and pupa of Eucoeliodes mirabilis (A. Villa & G. B. Villa, 1835) (Curculionidae: Ceutorhynchini) are described using drawings and SEM images and are compared and keyed with already described larvae of 58 other ceutorhynchinae taxa. The larval body has an effective combination of morphological adaptations that assist a unique biological defensive strategy. All larval stages of E. mirabilis feed ectophytically on leaves of Euonymus europaeus L. (Celastraceae), and the larval body is covered with a thick faecal shield. The fixation of this protective shield on the larval back is performed by a peculiar dorsal microsculpture composed of a dense carpet of microtrichia on the thorax and abdomen, which serves effectively as a velcro system. Because of this strategy, macrosetae on the larval and pupal body of E. mirabilis are completely reduced. Larvae of E. mirabilis also have distinct morphological adaptations for protecting the spiracles against intrusion of faeces and avoiding occlusion of the tracheal system: a) microtrichia around spiracles are slightly shorter, distinctly stronger and are arranged with high-density and in clusters and b) spiracles are protected by an external safety valve. This strategy of E. mirabilis larvae is unique, although somewhat similar to that of Criocerinae and Blepharida-group leave beetles (Galerucinae) (both Coleoptera: Chrysomelidae), but with distinctly different morphological adaptations. PMID:28125664

  18. Velcro-Like System Used to Fix a Protective Faecal Shield on Weevil Larvae.

    Directory of Open Access Journals (Sweden)

    Jiří Skuhrovec

    Full Text Available The last instar larva and pupa of Eucoeliodes mirabilis (A. Villa & G. B. Villa, 1835 (Curculionidae: Ceutorhynchini are described using drawings and SEM images and are compared and keyed with already described larvae of 58 other ceutorhynchinae taxa. The larval body has an effective combination of morphological adaptations that assist a unique biological defensive strategy. All larval stages of E. mirabilis feed ectophytically on leaves of Euonymus europaeus L. (Celastraceae, and the larval body is covered with a thick faecal shield. The fixation of this protective shield on the larval back is performed by a peculiar dorsal microsculpture composed of a dense carpet of microtrichia on the thorax and abdomen, which serves effectively as a velcro system. Because of this strategy, macrosetae on the larval and pupal body of E. mirabilis are completely reduced. Larvae of E. mirabilis also have distinct morphological adaptations for protecting the spiracles against intrusion of faeces and avoiding occlusion of the tracheal system: a microtrichia around spiracles are slightly shorter, distinctly stronger and are arranged with high-density and in clusters and b spiracles are protected by an external safety valve. This strategy of E. mirabilis larvae is unique, although somewhat similar to that of Criocerinae and Blepharida-group leave beetles (Galerucinae (both Coleoptera: Chrysomelidae, but with distinctly different morphological adaptations.

  19. In vitro effects of thiamethoxam on larvae of Africanized honey bee Apis mellifera (Hymenoptera: Apidae).

    Science.gov (United States)

    Tavares, Daiana Antonia; Roat, Thaisa Cristina; Carvalho, Stephan Malfitano; Silva-Zacarin, Elaine Cristina Mathias; Malaspina, Osmar

    2015-09-01

    Several investigations have revealed the toxic effects that neonicotinoids can have on Apis mellifera, while few studies have evaluated the impact of these insecticides can have on the larval stage of the honeybee. From the lethal concentration (LC50) of thiamethoxam for the larvae of the Africanized honeybee, we evaluated the sublethal effects of this insecticide on morphology of the brain. After determine the LC50 (14.34 ng/μL of diet) of thiamethoxam, larvae were exposed to a sublethal concentration of thiamethoxam equivalent to 1.43 ng/μL by acute and subchronic exposure. Morphological and immunocytochemistry analysis of the brains of the exposed bees, showed condensed cells and early cell death in the optic lobes. Additional dose-related effects were observed on larval development. Our results show that the sublethal concentrations of thiamethoxam tested are toxic to Africanized honeybees larvae and can modulate the development and consequently could affect the maintenance and survival of the colony. These results represent the first assessment of the effects of thiamethoxam in Africanized honeybee larvae and should contribute to studies on honey bee colony decline. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Exposure of fish larvae to hydrocarbon concentration fields generated by subsurface blowouts

    International Nuclear Information System (INIS)

    Rye, Henrik; Johansen, Oeistein; Reed, Mark; Ekrol, Narve; Xiong Deqi

    2000-01-01

    As the oil activity outside the Norwegian coast moves towards north, the potential for conflict with the fishing industry increases. Reasons for this are the presence of spawning areas for important fish stocks like herring and cod, and also the technical development of subsurface solutions for the oil exploration, in-creasing the risks for the occurrence of subsurface blowouts. The paper explains how this potential for conflict can be described by means of numerical modelling techniques. The Haltenbanken area outside the western coast of Norway is selected as a field case. The modelling work involves underwater plume modelling as well as 3D modelling of ocean currents. The results from these modelling works are then combined with the modelling of the far-field transport and dilution of the underwater plume, and also the modelling of the spreading and transport of larvae from spawning areas. By combining the calculation of the concentration fields with the spreading calculations of the larvae, the exposure of a total larvae population (one year stock) can be estimated. The paper concludes that under unfavourable conditions, the overlap between the hydrocarbon concentration fields and the geographical distribution of larvae at its most vulnerable stage may cause a significant impact on a population level. (Author)

  1. Occurrence and Intensity of Anisakid Nematode Larvae in Some Commercially Important Fish Species in Persian Gulf

    Directory of Open Access Journals (Sweden)

    Maryam DADAR

    2016-10-01

    Full Text Available Background: Anisakid nematodes are common parasites of fish, mammals, fish-eating birds, and reptiles with a worldwide distribution, causing diseases in human, fish and important economic losses.Methods: A preliminary epidemiological study was carried out on Anisakid nematodes larvae in some commercially important fish species to evaluate the anisakid nematode larvae from greater lizardfish, (Saurida tumbil, Japanese thread fin bream (Nemipterus japonicus, crocodile longtom (Tylosurus crocodilus crocodiles and longfin trevally (Carangoides armatus from the Persian Gulf of Iran.Result: The collected larvae were identified mainly as the third larval stage (L3 of Hysterothylacium larval type A, B and C, Anisakis sp., Raphidascaris sp., Pseudoterranova sp. and Philometra sp. (Nematoda: Philometridae. The prevalence of Anisakid larvae infection of examined fishes was 97.2% in N. japonicus, 90.3% in S. tumbil, 20.5% in crocodile longtom and 5.5% in longfin trevally. Anisakis type III for the first time was different from Anisakis type I and Anisakis type II.Discussion: Zoonotic anisakids by high prevalence in edible fish could be a health hazard for people. So health practices should be considered in these areas.

  2. Velcro-Like System Used to Fix a Protective Faecal Shield on Weevil Larvae.

    Science.gov (United States)

    Skuhrovec, Jiří; Stejskal, Robert; Trnka, Filip; di Giulio, Andrea

    2017-01-01

    The last instar larva and pupa of Eucoeliodes mirabilis (A. Villa & G. B. Villa, 1835) (Curculionidae: Ceutorhynchini) are described using drawings and SEM images and are compared and keyed with already described larvae of 58 other ceutorhynchinae taxa. The larval body has an effective combination of morphological adaptations that assist a unique biological defensive strategy. All larval stages of E. mirabilis feed ectophytically on leaves of Euonymus europaeus L. (Celastraceae), and the larval body is covered with a thick faecal shield. The fixation of this protective shield on the larval back is performed by a peculiar dorsal microsculpture composed of a dense carpet of microtrichia on the thorax and abdomen, which serves effectively as a velcro system. Because of this strategy, macrosetae on the larval and pupal body of E. mirabilis are completely reduced. Larvae of E. mirabilis also have distinct morphological adaptations for protecting the spiracles against intrusion of faeces and avoiding occlusion of the tracheal system: a) microtrichia around spiracles are slightly shorter, distinctly stronger and are arranged with high-density and in clusters and b) spiracles are protected by an external safety valve. This strategy of E. mirabilis larvae is unique, although somewhat similar to that of Criocerinae and Blepharida-group leave beetles (Galerucinae) (both Coleoptera: Chrysomelidae), but with distinctly different morphological adaptations.

  3. Sekuens Gen Protein Kapsid Mayor L1 Human Papilomavirus 16 dari Isolat Klinik Asal Bandung

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    Anandayu Pradita

    2014-09-01

    Full Text Available Cervical cancer is strongly associated with chronic human papillomavirus (HPV infection. HPV-16 is the most prevalent genotype infecting cervical epithelium. The major coat protein of viral particle (L1 plays a key role in the infection process. Our study aimed to isolate the HPV-16 L1 gene and analyze its sequence. Samples used were samples collected from the Department of Obstetrics and Gynaecology, Dr. Hasan Sadikin General Hospital, Bandung during the period of June to October 2010. In this study, the HPV-16 L1 sequence was analyzed from the viral deoxyribonucleic acid (DNA extracted from biopsy sample of cervical cancer patient biopsy samples.The HPV-16