206 research outputs found

    Primary Production and Carbon Allocation in Creosotebush

    Get PDF

    Primary Production and Carbon Allocation in Creosotebush

    Get PDF

    A Phase I Double Blind, Placebo-Controlled, Randomized Study of the Safety and Immunogenicity of Electroporated HIV DNA with or without Interleukin 12 in Prime-Boost Combinations with an Ad35 HIV Vaccine in Healthy HIV-Seronegative African Adults.

    No full text
    Strategies to enhance the immunogenicity of DNA vaccines in humans include i) co-administration of molecular adjuvants, ii) intramuscular administration followed by in vivo electroporation (IM/EP) and/or iii) boosting with a different vaccine. Combining these strategies provided protection of macaques challenged with SIV; this clinical trial was designed to mimic the vaccine regimen in the SIV study.Seventy five healthy, HIV-seronegative adults were enrolled into a phase 1, randomized, double-blind, placebo-controlled trial. Multi-antigenic HIV (HIVMAG) plasmid DNA (pDNA) vaccine alone or co-administered with pDNA encoding human Interleukin 12 (IL-12) (GENEVAX IL-12) given by IM/EP using the TriGrid Delivery System was tested in different prime-boost regimens with recombinant Ad35 HIV vaccine given IM.All local reactions but one were mild or moderate. Systemic reactions and unsolicited adverse events including laboratory abnormalities did not differ between vaccine and placebo recipients. No serious adverse events (SAEs) were reported. T cell and antibody response rates after HIVMAG (x3) prime-Ad35 (x1) boost were independent of IL-12, while the magnitude of interferon gamma (IFN-γ) ELISPOT responses was highest after HIVMAG (x3) without IL-12. The quality and phenotype of T cell responses shown by intracellular cytokine staining (ICS) were similar between groups. Inhibition of HIV replication by autologous T cells was demonstrated after HIVMAG (x3) prime and was boosted after Ad35. HIV specific antibodies were detected only after Ad35 boost, although there was a priming effect with 3 doses of HIVMAG with or without IL-12. No anti-IL-12 antibodies were detected.The vaccines were safe, well tolerated and moderately immunogenic. Repeated administration IM/EP was well accepted. An adjuvant effect of co-administered plasmid IL-12 was not detected.ClinicalTrials.gov NCT01496989

    Evaluation of ground-level and space-borne sensor as tools in monitoring nitrogen nutrition status in immature and mature oil palm

    Get PDF
    Monitoring nitrogen (N) in oil palm is crucial for the production sustainability. The objective of this study is to examine the capability of visible (Vis), near infrared (NIR) and a combination of Vis and NIR (Vis + NIR) spectral indices acquired from different sensors for predicting foliar N content of different palm age groups. The N treatments varied from 0 to 2 kg per palm, subjected according to immature, young mature and prime mature classes. The Vis + NIR indices from the ground level-sensor that is green + red + NIR (G + R + NIR) was the best index for predicting N for immature palms (R2 = 0.91), while Vis indices blue + red (B + R) and Green Red Index from the space-borne sensor were significantly useful for N assessment of young and prime mature palms (R2 = 0.70 and 0.50), respectively. The application of vegetation indices for monitoring N status of oil palm is beneficial to examine extensive plantation areas

    Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus

    Full text link
    The photosynthetic responses to a flowering-inductive water-stress period and recovery were studied and compared in two Citrus species. Under greenhouse conditions, Fino lemon and Owari satsuma trees were subjected to moderate (-2 MPa at predawn) and severe (-3 MPa) water stress levels and were re-watered after 60 days. Vegetative growth was inhibited during the stress assays, and strong defoliation levels were reported, especially in Fino lemon. In both species, bud sprouting was induced after re-watering. Flowers and vegetative shoots developed in Owari satsuma after a drought period, and the development was independent of the stress level. In Fino lemon, vegetative shoots and flowers were primarily formed after moderate and severe stress, respectively. The photosynthetic rate and stomatal conductance were reduced by water stress, and a marked increase in water-use efficiency at the moderate water deficit level was observed. Nevertheless, the photosynthetic apparatus was not damaged, since the maximum quantum yield, photosynthetic pigment concentrations and Rubisco level and activity did not change. Furthermore, the measured malonyldialdehyde (MDA) and peroxidase activity indicated that oxidative stress was not specifically triggered by water stress in our study. Therefore, the gas exchange, fluorescence and biochemical parameters suggested that diffusional limitations to photosynthesis predominated in both of the studied Citrus species, and explained the rapid recovery of the photosynthetic parameters after rehydration. The net CO 2 fixation rate and stomatal conductance were recovered within 24 h in Fino lemon, whereas 3 days were required in Owari satsuma. This suggests the presence of some metabolic limitations in the latter species. Furthermore, the sensibility of the defoliation rates, the accumulation of proline and the stomatal behaviour in response to water stress indicated a higher drought tolerance of Fino lemon, according to its better acclimation to hot climates. © 2011 Springer-Verlag.The authors thank Dr. J. Moreno and co-workers from the Departamento de Bioquimica of the Universidad de Valencia for his help and support in the Rubisco assays, and Dr. F. Fornes, Dr. A. Calatayud and Dr. E. Primo-Millo for the critical review of the manuscript. This work was funded by the Universitat Politecnica de Valencia, Spain (Ayudas para primeros proyectos de investigacion PAID06-06).Ávila Reséndiz, C.; Guardiola Barcena, JL.; González Nebauer, S. (2012). Response of the photosynthetic apparatus to a flowering-inductive period by water stress in Citrus. Trees - Structure and Function. 26(3):833-840. https://doi.org/10.1007/s00468-011-0657-4S833840263Addicott FT (1982) Abscission. University of California Press, BerkeleyBajji M, Kinet JM, Lutts S (1998) Salt stress effects on roots and leaves of Atriplex halimus L. and their corresponding callus. Plant Sci 137:131–142Barbera G, Fatta-del-Bosco G, Lo-Cascio B (1985) Effect of water stress on lemon summer bloom: the Forzatura technique in the Sicilian citrus industry. Acta Hortic 171:391–397Bates LS, Waldren RP, Teare ID (1973) Rapid determination of free proline for water stress studies. Plant Soil 39:205–207Bota J, Medrano H, Flexas J (2004) Is photosynthesis limited by decreased Rubisco activity and RuBP content under progressive water stress? New Phytol 162:671–681Bradford MM (1976) A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72:248–254Cassin J, Bourdeaut A, Fougue V, Furon V, Gaillard JP, LeBourdelles J, Montagut G, Moreuil C (1969) The influence of climate upon blooming of Citrus in tropical areas. Proc Int Soc Citrus 1:315–323Castel JR, Buj A (1990) Response of Salustiana oranges to high frequency deficit irrigation. Irrig Sci 11:121–127Chaikiatitiyos S, Menzel CM, Rasmussen TS (1994) Floral induction in tropical fruit trees: effects of temperature and water supply. J Hortic Sci 69:397–415Chaves MM, Flexas J, Pinheiro C (2009) Photosynthesis under drought and salt stress: regulation mechanisms from whole plant to cell. Ann Bot 103:551–560Costa JM, Ortuño MF, Chaves M (2007) Deficit irrigation as a strategy to save water: physiology and potential application to horticulture. J Integr Plant Biol 49:1421–1434Davenport TL (1990) Citrus flowering. Hortic Rev 12:249–408Davies FS, Albrigo LG (1994) Citrus. CAB International, Wallingford, pp 126–134Domingo R, Ruiz-Sánchez MC, Sánchez-Blanco MJ, Torrecillas A (1996) Water relations, growth and yield of Fino lemon trees under regulated deficit irrigation. Irrig Sci 16:115–123Erismann ND, Machado EC, Tucci MLS (2008) Photosynthetic limitation by CO2 diffusion in drought stressed orange leaves on three rootstocks. Photosynth Res 96:163–172Flexas J, Bota J, Galmés J, Medrano H, Ribas-Carbó M (2006) Keeping a positive carbon balance under adverse conditions: responses of photosynthesis and respiration to water stress. Physiol Plant 127:343–352Gallé A, Florez-Sarasa I, Tomas M, Pou A, Medrano H, Ribas-Carbó M, Flexas J (2009) The role of mesophyll conductance during water stress and recovery in tobacco (Nicotiana sylvestris): acclimation or limitation? J Exp Bot 60:2379–2390Galmés J, Medrano H, Flexas J (2007) Photosynthetic limitations in response to water stress and recovery in Mediterrenean plants with different growth forms. New Phytol 175:81–93García-Luis A, Kanduser M, Santamarina P, Guardiola JL (1992) Low temperature influence on flowering in Citrus. The separation of inductive and bud dormancy releasing effects. Physiol Plant 86:648–652García-Sánchez F, Syvertsen JP, Gimeno V, Botía P, Pérez-Pérez JG (2007) Responses to flooding and drought stress by two citrus rootstock seedlings with different water-use efficiency. Physiol Plant 130:532–542Genty B, Briantais JM, Baker NR (1989) The relationship between quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence. Biochim Biophys Acta 990:87–92Gómez-Cadenas A, Tadeo FR, Talon M, Primo-Millo E (1996) Leaf abscission induced by ethylene in water-stressed intact seedlings of Cleopatra mandarin requires previous abscisic acid accumulation in roots. Plant Physiol 112:401–408Gordo O, Sanz JJ (2010) Impact of climate change on plant phenology in Mediterranean ecosystems. Glob Chang Biol 16:1082–1106Heath RL, Packer L (1968) Photoperoxidation in isolated chloroplasts. I. Kinetics and stoichiometry of fatty acid peroxidation. Arch Biochem Biophys 125:189–190Hoagland DR, Arnon DI (1950) The water culture method for growing plants without soil. California Agricultural Experiment Station Circular no. 347, p 32IPCC (2001) Climate change 2001. In: Houghton JT (ed) The scientific basis. Cambridge University Press, CambridgeLawlor DW (1995) The effects of water deficit on photosynthesis. In: Smirnoff N (ed) Environment and plant metabolism. Bios Scientific Publishers, Oxford, pp 129–160Lichtenthaler HK, Buschmann C (2001) Current protocols in food analytical chemistry, F4.2.1 and F4.3.1. John Wiley and Sons, Inc, NJLorimer GH, Badger MR, Andrews TJ (1977) D-Ribulose-1, 5-bisphosphate carboxilase-oxigenase. Improved methods for activation and assay of catalytic activities. Anal Biochem 78:66–75Miyashita K, Tanakamaru S, Maitani T, Kimura K (2005) Recovery responses of photosynthesis, transpiration, and stomatal conductance in kidney bean following drought stress. Environ Exp Bot 53:205–214Nir I, Leshem B, Goren R (1972) Effects of water stress, gibberellic acid and 2-chloroethylammoniumchloride (CCC) ob flower differentiation in Eureka lemon trees. J Am Soc Hortic Sci 97:774–778Peñarrubia L, Moreno J (1988) Ribulose 1, 5-bisphosphate carboxylase oxygenase from citrus leaves. Phytochemistry 27:1999–2004Pérez-Pérez JG, Syvertsen JP, Botía P, García-Sánchez F (2007) Leaf water relations and net gas exchange responses of salinized carrizo citrange seedlings during drought stress and recovery. Ann Bot 100:335–345Pérez-Pérez JG, Robles JM, Tovar JC, Botía P (2009) Response to drought and salt stress of lemon ‘Fino 49’ under field conditions: water relations, osmotic adjustment and gas Exchange. Sci Hortic 122:83–90Reynolds M, Tuberosa R (2008) Translational research impacting on crop productivity in drought-prone environments. Curr Opin Plant Biol 11:171–179Ruiz-Sánchez MC, Domingo R, Savé R, Biel C, Torrecillas A (1997) Effects of water stress and rewatering on leaf water relations of lemon plants. Biol Plant 39:623–631Sarris D, Christodoulakis D, Körner C (2007) Recent decline in precipitation and tree growth in the eastern Mediterranean. Glob Chang Biol 13:1187–1200Sharkey TD (1990) Water-stress effects on photosynthesis. Photosynthetica 24:651Southwick SM, Davenport TL (1986) Characterization of water stress and low temperature effects on flower induction in Citrus. Plant Physiol 81:26–29Spiegel-Roy P, Goldschmidt EE (1996) Biology of Citrus. Cambridge University Press, Cambridge, pp 131–136Syvertsen JP, Lloyd J (1994) Citrus. In: Schaffer BA, Andersen PC (eds) Handbook of environmental physiology of fruit crops. Vol II Subtropical and tropical crops. CRC Press, Boca Raton, pp 65–99Syvertsen JP (1996) Water stress and carbon budgets. Proc Int Soc Citrus 1:46–50Valladares F, Arrieta S, Aranda I, Lorenzo D, Sánchez-Gómez D, Tena D, Suarez F, Pardos JA (2005) Shade tolerance, photoinhibition sensitivity and phenotypic plasticity of Illex aquifolium in continental Mediterranean sites. Tree Physiol 25:1041–1052Vu JCV, Yelenosky G (1988) Solar irradiance and drought stress effects on the activity and concentration of ribulose bisphosphate carboxylase in ‘Valencia’ orange leaves. Isr J Bot 37:245–25

    Headache in juvenile myoclonic epilepsy

    Get PDF
    The objective of this study was to assess the prevalence of and risk factors for primary headaches in juvenile myoclonic epilepsy (JME). Headache was classified in 75 patients with JME using a questionnaire, and its prevalence was correlated with the literature on the general population and clinical data. Headache was present in 47 patients. Thirty-one had migraine [20 migraine without aura (MO), 11 migraine with aura (MA)]. Fourteen patients with migraine had tension-type headache (TTH) in addition. Sixteen had only TTH. Comparison with the general population revealed a significantly higher prevalence of migraine (RR 4.4), MO (3.6), MA (7.3) and TTH (3.4) in JME. Risk factors for migraine and MO were female gender and for MA family history of migraine in first-degree relatives. Migraine and MA were associated with fairly controlled generalized tonic clonic seizures, MO with absences. Together with its strong genetic background, JME appears to be an attractive homogenous subtype of epilepsy for genetic research on migraine

    Trait impulsivity in Juvenile Myoclonic Epilepsy

    Get PDF
    Impulsivity is a multidimensional construct that can predispose to psychopathology. Meta‐analysis demonstrates an association between response impulsivity and Juvenile Myoclonic Epilepsy (JME), a common genetic generalized epilepsy. Here, we test the hypotheses that trait impulsivity is (i) elevated in JME compared to controls; (ii) moderated by specific seizure characteristics; and (iii) associated with psychiatric adverse effects of antiepileptic drugs (AEDs)
    corecore