116 research outputs found

    Circulating DNA: Diagnostic Tool and Predictive Marker for Overall Survival of NSCLC Patients

    Get PDF
    PURPOSE: The purpose of our study was to determine whether the amounts of circulating DNA (cDNA) could discriminate between NSCLC patients and healthy individuals and assess its value as a prognostic marker of this disease. METHODS: We conducted a study of 309 individuals and the cDNA levels were assessed through real-time PCR methodology. RESULTS: We found increased cDNA levels in NSCLC patients compared to control individuals. We also found a decreased overall survival time in patients presenting high cDNA levels, when compared to lower cDNA concentrations. CONCLUSIONS: Quantification of cDNA may be a good tool for NSCLC detection with potential for clinical applicability

    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

    Pregnancy Outcome and Placenta Pathology in Plasmodium berghei ANKA Infected Mice Reproduce the Pathogenesis of Severe Malaria in Pregnant Women

    Get PDF
    Pregnancy-associated malaria (PAM) is expressed in a range of clinical complications that include increased disease severity in pregnant women, decreased fetal viability, intra-uterine growth retardation, low birth weight and infant mortality. The physiopathology of malaria in pregnancy is difficult to scrutinize and attempts were made in the past to use animal models for pregnancy malaria studies. Here, we describe a comprehensive mouse experimental model that recapitulates many of the pathological and clinical features typical of human severe malaria in pregnancy. We used P. berghei ANKA-GFP infection during pregnancy to evoke a prominent inflammatory response in the placenta that entails CD11b mononuclear infiltration, up-regulation of MIP-1 alpha chemokine and is associated with marked reduction of placental vascular spaces. Placenta pathology was associated with decreased fetal viability, intra-uterine growth retardation, gross post-natal growth impairment and increased disease severity in pregnant females. Moreover, we provide evidence that CSA and HA, known to mediate P. falciparum adhesion to human placenta, are also involved in mouse placental malaria infection. We propose that reduction of maternal blood flow in the placenta is a key pathogenic factor in murine pregnancy malaria and we hypothesize that exacerbated innate inflammatory responses to Plasmodium infected red blood cells trigger severe placenta pathology. This experimental model provides an opportunity to identify cell and molecular components of severe PAM pathogenesis and to investigate the inflammatory response that leads to the observed fetal and placental blood circulation abnormalities

    Understanding How Microplastics Affect Marine Biota on the Cellular Level Is Important for Assessing Ecosystem Function: A Review

    Get PDF
    Plastic has become indispensable for human life. When plastic debris is discarded into waterways, these items can interact with organisms. Of particular concern are microscopic plastic particles (microplastics) which are subject to ingestion by several taxa. This review summarizes the results of cutting-edge research about the interactions between a range of aquatic species and microplastics, including effects on biota physiology and secondary ingestion. Uptake pathways via digestive or ventilatory systems are discussed, including (1) the physical penetration of microplastic particles into cellular structures, (2) leaching of chemical additives or adsorbed persistent organic pollutants (POPs), and (3) consequences of bacterial or viral microbiota contamination associated with microplastic ingestion. Following uptake, a number of individual-level effects have been observed, including reduction of feeding activities, reduced growth and reproduction through cellular modifications, and oxidative stress. Microplastic-associated effects on marine biota have become increasingly investigated with growing concerns regarding human health through trophic transfer. We argue that research on the cellular interactions with microplastics provide an understanding of their impact to the organisms’ fitness and, therefore, its ability to sustain their functional role in the ecosystem. The review summarizes information from 236 scientific publications. Of those, only 4.6% extrapolate their research of microplastic intake on individual species to the impact on ecosystem functioning. We emphasize the need for risk evaluation from organismal effects to an ecosystem level to effectively evaluate the effect of microplastic pollution on marine environments. Further studies are encouraged to investigate sublethal effects in the context of environmentally relevant microplastic pollution conditions

    Bottom trawl fishing footprints on the world’s continental shelves

    Get PDF
    Bottom trawlers land around 19 million tons of fish and invertebrates annually, almost one-quarter of wild marine landings. The extent of bottom trawling footprint (seabed area trawled at least once in a specified region and time period) is often contested but poorly described. We quantify footprints using high-resolution satellite vessel monitoring system (VMS) and logbook data on 24 continental shelves and slopes to 1,000-m depth over at least 2 years. Trawling footprint varied markedly among regions: from 50% in some European seas. Overall, 14% of the 7.8 million-km2 study area was trawled, and 86% was not trawled. Trawling activity was aggregated; the most intensively trawled areas accounting for 90% of activity comprised 77% of footprint on average. Regional swept area ratio (SAR; ratio of total swept area trawled annually to total area of region, a metric of trawling intensity) and footprint area were related, providing an approach to estimate regional trawling footprints when high-resolution spatial data are unavailable. If SAR was ≤0.1, as in 8 of 24 regions, there was >95% probability that >90% of seabed was not trawled. If SAR was 7.9, equal to the highest SAR recorded, there was >95% probability that >70% of seabed was trawled. Footprints were smaller and SAR was ≤0.25 in regions where fishing rates consistently met international sustainability benchmarks for fish stocks, implying collateral environmental benefits from sustainable fishing

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Bottom trawl fishing footprints on the world’s continental shelves

    Get PDF
    Publication history: Accepted - 23 August 2018; Published online - 8 October 2018.Bottom trawlers land around 19 million tons of fish and invertebrates annually, almost one-quarter of wild marine landings. The extent of bottom trawling footprint (seabed area trawled at least once in a specified region and time period) is often contested but poorly described. We quantify footprints using high-resolution satellite vessel monitoring system (VMS) and logbook data on 24 continental shelves and slopes to 1,000-m depth over at least 2 years. Trawling footprint varied markedly among regions: from <10% of seabed area in Australian and New Zealand waters, the Aleutian Islands, East Bering Sea, South Chile, and Gulf of Alaska to >50% in some European seas. Overall, 14% of the 7.8 million-km2 study area was trawled, and 86% was not trawled. Trawling activity was aggregated; the most intensively trawled areas accounting for 90% of activity comprised 77% of footprint on average. Regional swept area ratio (SAR; ratio of total swept area trawled annually to total area of region, a metric of trawling intensity) and footprint area were related, providing an approach to estimate regional trawling footprints when highresolution spatial data are unavailable. If SAR was ≤0.1, as in 8 of 24 regions, therewas >95% probability that >90%of seabed was not trawled. If SAR was 7.9, equal to the highest SAR recorded, there was >95% probability that >70% of seabed was trawled. Footprints were smaller and SAR was ≤0.25 in regions where fishing rates consistently met international sustainability benchmarks for fish stocks, implying collateral environmental benefits from sustainable fishing.Funding for meetings of the study group and salary support for R.O.A. were provided by the following: David and Lucile Packard Foundation; the Walton Family Foundation; the Alaska Seafood Cooperative; American Seafoods Group US; Blumar Seafoods Denmark; Clearwater Seafoods Inc.; Espersen Group; Glacier Fish Company LLC US; Gortons Seafood; Independent Fisheries Limited N.Z.; Nippon Suisan (USA), Inc.; Pesca Chile S.A.; Pacific Andes International Holdings, Ltd.; San Arawa, S.A.; Sanford Ltd. N.Z.; Sealord Group Ltd. N.Z.; South African Trawling Association; Trident Seafoods; and the Food and Agriculture Organisation of the United Nations. Additional funding to individual authors was provided by European Union Project BENTHIS EU-FP7 312088 (to A.D.R., O.R.E., F.B., N.T.H., L.B.-M., R.C., H.O.F., H.G., J.G.H., P.J., S.K., M.L., G.G.-M., N.P., P.E.P., T.R., A.S., B.V., and M.J.K.); the Instituto Português do Mar e da Atmosfera, Portugal (C.S.); the International Council for the Exploration of the Sea Science Fund (R.O.A. and K.M.H.); the Commonwealth Scientific and Industrial Research Organisation (C.R.P. and T.M.); the National Oceanic and Atmospheric Administration (R.A.M.); New Zealand Ministry for Primary Industries Projects BEN2012/01 and DAE2010/ 04D (to S.J.B. and R.F.); the Institute for Marine and Antarctic Studies, University of Tasmania and the Department of Primary Industries, Parks, Water and Environment, Tasmania, Australia (J.M.S.); and UK Department of Environment, Food and Rural Affairs Project MF1225 (to S.J.)
    corecore