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Greater Accumulation (greater + accumulation)
Selected AbstractsOverload-induced skeletal muscle extracellular matrix remodelling and myofibre growth in mice lacking IL-6ACTA PHYSIOLOGICA, Issue 4 2009J. P. White Abstract Aim:, Overloading healthy skeletal muscle produces myofibre hypertrophy and extracellular matrix remodelling, and these processes are thought to be interdependent for producing muscle growth. Inflammatory cytokine interleukin-6 (IL-6) gene expression is induced in overloaded skeletal muscle, and the loss of this IL-6 induction can attenuate the hypertrophic response to overload (OV). Although the OV induction of IL-6 in skeletal muscle may be an important regulator of inflammatory processes and satellite cell proliferation, less is known about its role in the regulation of extracellular matrix remodelling. The purpose of the current study was to examine if OV-induced extracellular matrix remodelling, muscle growth, and associated gene expression were altered in mice that lack IL-6, when compared with wild-type mice. Methods:, Male C57/BL6 (WT) and C57/BL6 × IL-6,/, (IL-6,/,) mice (10 weeks of age) were assigned to either a sham control or synergist ablation OV treatments for 3, 21 or 56 days. Result:, Plantaris muscle mass increased 59% in WT and 116% in IL-6,/, mice after 21 day OV. Myofibre CSA was also increased by 21 day OV in both WT and IL-6,/, mice. OV induced a twofold greater increase in the volume of non-contractile tissue in IL-6,/, muscle compared to WT. OV also induced a significantly greater accumulation of hydroxyproline and procollagen-1 mRNA in IL-6,/, muscle, when compared with WT muscle after 21 day OV. Transforming growth factor-, and insulin-like growth factor-1 mRNA expression were also induced to a greater extent in IL-6,/, muscle when compared with WT muscle after 21 day OV. There was no effect of IL-6 loss on the induction of myogenin, and cyclin D1 mRNA expression after 3 day OV. However, MyoD mRNA expression in 3 day OV IL-6,/, muscle was attenuated when compared with WT OV mice. Conclusion:, IL-6 appears to be necessary for the normal regulation of extracellular matrix remodelling during OV-induced growth. [source] Ecohydrological controls on snowmelt partitioning in mixed-conifer sub-alpine forestsECOHYDROLOGY, Issue 2 2009Noah P. Molotch Abstract We used co-located observations of snow depth, soil temperature, and moisture and energy fluxes to monitor variability in snowmelt infiltration and vegetation water use at mixed-conifer sub-alpine forest sites in the Valles Caldera, New Mexico (3020 m) and on Niwot Ridge, Colorado (3050 m). At both sites, vegetation structure largely controlled the distribution of snow accumulation with 29% greater accumulation in open versus under-canopy locations. Snow ablation rates were diminished by 39% in under-canopy locations, indicating increases in vegetation density act to extend the duration of the snowmelt season. Similarly, differences in climate altered snow-season duration, snowmelt infiltration and evapotranspiration. Commencement of the growing season was coincident with melt-water input to the soil and lagged behind springtime increases in air temperature by 12 days on average, ranging from 2 to 33 days under warmer and colder conditions, respectively. Similarly, the timing of peak soil moisture was highly variable, lagging behind springtime increases in air temperature by 42 and 31 days on average at the Colorado and New Mexico sites, respectively. Latent heat flux and associated evaporative loss to the atmosphere was 28% greater for the year with earlier onset of snowmelt infiltration. Given the large and variable fraction of precipitation that was partitioned into water vapour loss, the combined effects of changes in vegetation structure, climate and associated changes to the timing and magnitude of snowmelt may have large effects on the partitioning of snowmelt into evapotranspiration, surface runoff and ground water recharge. Copyright © 2009 John Wiley & Sons, Ltd. [source] Effects of Salinity and Mixed Ammonium and Nitrate Nutrition on the Growth and Nitrogen Utilization of BarleyJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2001A. Ali The absorption and utilization of nitrogen (N) by plants are affected by salinity and the form of N in the root medium. A hydroponic study was conducted under controlled conditions to investigate growth and N uptake by barley (Hordeum vulgare L.) supplied with five different NH4+ -N/NO3, -N ratios at electrical conductivity of 0 and 8 dS m,1. The five NH4+ -N/NO3 -N ratios were 0/100, 25/75, 50/50, 75/25 and 100/0, each giving a total N supply of 100 mg N l,1 in the root medium. A mixed N supply of NH4+ and NO3, resulted in greater accumulation of N in plants than either NO3, or NH4+ as the sole N source. Plants produced a significantly higher dry matter yield when grown with mixed N nutrition than with NH4+ or NO3, alone. Total dry matter production and root and shoot N contents decreased with increasing salinity in the root medium. The interaction between salinity and N nutrition was found to be significant for all the variables. A significant positive correlation (r=0.97) was found between nitrogen level in the plant shoot and its dry matter yield. Wachstum und Stickstoffausnutzung bei Gerste in Abhängigkeit von Versalzung und Michungen von Ammonium und Nitrat Aufnahme und Nutzung von N durch Pflanzen wird von der Versalzung und N-Form im Wurzelbereich bestimmt. Es wurde in Hydrokultur unter kontrollierten Bedingungen Wachstum und N-Aufnahme durch Gerste (Hordeum vulgare L.) bei Anwendung von fünf unterschiedlichen NH4+ -N/NO3, -N Verhältnissen bei einer elektrischen Konduktivität von 0 und 8 dS m,1 untersucht. Die Gesamtmenge von 100 mg N l,1 im Wurzelmedium wies NH4+ -N/NO3, -N Verhältnisse von 0/100, 25/75, 50/50, 75/25 und 100/0 auf. Mischungen von NH4+ und NO3, führten zu einer größeren Aufnahme durch die Pflanzen als bei alleiniger Anwendung von NO3, oder NH4+. Die Pflanzen produzierten signifikant mehr Gesamttrockenmasse mit Mischungen der beiden N-Formen im Vergleich zu alleiniger Anwendung von NH4+ oder NO3,. Die Gesamttrockenmasse sowie die N-Gehalte von Wurzel und Sproß nahmen mit steigender Versalzung ab. Versalzungs- und N-Versorgungs-Interaktion war signifikant in allen Versuchsbedingungen. Eine signifikante positive Korrelation (r=0,97) wurde zwischen Stickstoffkonzentration und der Trockenmasseproduktion der Pflanze gefunden. [source] Influence of temperature on silver accumulation and depuration in rainbow troutJOURNAL OF FISH BIOLOGY, Issue 6 2004J. W. Nichols To assess the influence of water temperature on silver uptake, rainbow trout Oncorhynchus mykiss(c. 50 g; held at 13° C) were exposed to 0·1 ,M AgNO3 in ion-poor water for 1 week at 4 and 16° C without previous temperature acclimation. To assess the influence of temperature on elimination of previously accumulated Ag, rainbow trout were exposed to 0·1 ,M AgNO3 in ion-poor water for 1 week at 12° C, then were randomly divided amongst two Ag-free water containers, differing only in temperature (3 and 16° C), for 2 months. In the uptake study greater accumulation of Ag was seen in the gills, plasma and especially the livers and bile of ,warm' rainbow trout (16° C) compared to ,cold' rainbow trout (4° C), which can be explained by the higher metabolic rates of the warmer fish. In the depuration study there was no net elimination of Ag from the livers and bile but there was biphasic elimination of Ag from the gills and plasma of ,warm' and ,cold' fish, but with few differences between them. This indicated that temperature-dependent processes were less important in Ag elimination than in Ag uptake. Toxicokinetic modelling of Ag uptake by livers indicated four-fold greater uptake of Ag by ,warm' rainbow trout compared to ,cold' rainbow trout (one compartment uptake model). Elimination of previously accumulated Ag from the plasma was best fitted by a two compartment rate-constant based model, with approximately half the plasma Ag load eliminated within 24 h, followed by slower elimination of Ag over 2 months. [source] Striatal regulation of ,FosB, FosB, and cFos during cocaine self-administration and withdrawalJOURNAL OF NEUROCHEMISTRY, Issue 1 2010Erin B. Larson J. Neurochem. (2010) 115, 112,122. Abstract Chronic drug exposure induces alterations in gene expression profiles that are thought to underlie the development of drug addiction. The present study examined regulation of the Fos-family of transcription factors, specifically cFos, FosB, and ,FosB, in striatal subregions during and after chronic intravenous cocaine administration in self-administering and yoked rats. We found that cFos, FosB, and ,FosB exhibit regionally and temporally distinct expression patterns, with greater accumulation of ,FosB protein in the nucleus accumbens (NAc) shell and core after chronic cocaine administration, whereas ,FosB increases in the caudate-putamen (CPu) remained similar with either acute or chronic administration. In contrast, tolerance developed to cocaine-induced mRNA for ,FosB in all three striatal subregions with chronic administration. Tolerance also developed to FosB expression, most notably in the NAc shell and CPu. Interestingly, tolerance to cocaine-induced cFos induction was dependent on volitional control of cocaine intake in ventral but not dorsal striatal regions, whereas regulation of FosB and ,FosB was similar in cocaine self-administering and yoked animals. Thus, ,FosB-mediated neuroadaptations in the CPu may occur earlier than previously thought with the initiation of intravenous cocaine use and, together with greater accumulation of ,FosB in the NAc, could contribute to addiction-related increases in cocaine-seeking behavior. [source] PGPR and entomopathogenic fungus bioformulation for the synchronous management of leaffolder pest and sheath blight disease of ricePEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 5 2010Loganathan Karthiba Abstract BACKGROUND: The biological control of plant pests and diseases using a single organism has been reported to give inconsistent and poor performance. To improve the efficacy, bioformulations were developed possessing mixtures of bioagents. RESULTS: Bioformulations combining Pseudomonas fluorescens Migula strains Pf1 and AH1 and Beauveria bassiana (Balsamo) Vuill. isolate B2 were developed and tested for their efficacy against leaffolder pest and sheath blight disease on rice under glasshouse and field conditions. The combination of Pf1, AH1 and B2 effectively reduced the incidence of leaffolder insect and sheath blight disease on rice compared with other treatments. An in vitro assay of leaffolder preference to rice leaf tissues treated with Pf1 + AH1 + B2 biformulation showed variation from normal growth and development of leaffolder larvae. Plants treated with the Pf1 + AH1 + B2 combination showed a greater accumulation of enzymes, lipoxygenase and chitinase activity against leaffolder insect compared with other treatments. Similarly, the plants showed a higher accumulation of defence enzymes, peroxidase and polyphenol oxidase activity against sheath blight pathogen in Pf1 + AH1 + B2 treatment compared with the untreated control. The bioformulation mixture attracted the natural enemy population of leaffolder under field conditions. In addition, a significant increase in rice grain yield was observed in Pf1 + AH1 + B2 treatment compared with the untreated control. CONCLUSION: The combination of P. fluorescens strains and B. bassiana isolate effectively reduced the incidence of leaffolder insect and sheath blight disease on rice plants and showed the possibility of controlling both pest and disease using a single bioformulation. Copyright © 2010 Society of Chemical Industry [source] Electrophysiological properties of two axonal sodium channels, Nav1.2 and Nav1.6, expressed in mouse spinal sensory neuronesTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005Anthony M. Rush Sodium channels Nav1.2 and Nav1.6 are both normally expressed along premyelinated and myelinated axons at different stages of maturation and are also expressed in a subset of demyelinated axons, where coexpression of Nav1.6 together with the Na+/Ca2+ exchanger is associated with axonal injury. It has been difficult to distinguish the currents produced by Nav1.2 and Nav1.6 in native neurones, and previous studies have not compared these channels within neuronal expression systems. In this study, we have characterized and directly compared Nav1.2 and Nav1.6 in a mammalian neuronal cell background and demonstrate differences in their properties that may affect neuronal behaviour. The Nav1.2 channel displays more depolarized activation and availability properties that may permit conduction of action potentials, even with depolarization. However, Nav1.2 channels show a greater accumulation of inactivation at higher frequencies of stimulation (20,100 Hz) than Nav1.6 and thus are likely to generate lower frequencies of firing. Nav1.6 channels produce a larger persistent current that may play a role in triggering reverse Na+/Ca2+ exchange, which can injure demyelinated axons where Nav1.6 and the Na+/Ca2+ exchanger are colocalized, while selective expression of Nav1.2 may support action potential electrogenesis, at least at lower frequencies, while producing a smaller persistent current. [source] Effects of partial rootzone drying on yield, ripening and berry ABA in potted Tempranillo grapevines with split rootsAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2006M. CARMEN ANTOLÍN Abstract Our objective was to investigate whether grape berry growth and colour development is associated with variation in abscisic acid (ABA) levels during ripening under an irrigation regime of partial rootzone drying (PRD). The study was carried out using container-grown Tempranillo grapevines (established as fruit-bearing cuttings) with a split root system (occupying two contiguous pots) and grown under controlled conditions. Three irrigation treatments were imposed , a control (well watered), and two forms of deficit irrigation, viz. partial rootzone drying (PRD), and sustained deficit irrigation (SDI). Under SDI, a given volume of irrigation water was applied uniformly and simultaneously to both sides of the split roots of each vine. Under the PRD regime, the same total volume of irrigation was applied, but as separate allocations to each side of the split root system in turn, and alternating on a 10-day cycle. Because both deficit treatments received the same total amount of irrigation water (about 50% of the volume applied to controls), we were able to distinguish between the effects of deficit irrigation per se, versus any specific impact PRD might be having on vine performance. Outcomes were as follows. Compared to well-watered control vines, yield per plant, and weight per bunch were both reduced significantly under SDI, but were sustained close to control values under the PRD regime. SDI and PRD thus differed significantly in their respective impacts on vine performance, and comparing just these two forms of deficit irrigation, PRD resulted in greater yield, higher bunch weight, bigger leaf area and increased berry weight compared with the SDI treatment. Moreover, PRD also induced greater accumulation of skin anthocyanins at harvest, compared to SDI. Berry ABA concentration increased continuously throughout veraison, achieving a maximum at the end of this period. The increase of berry ABA concentration was earlier and faster in PRD than in SDI, which exhibited only a slight increase in berry ABA by the end of veraison. These distinctive responses to PRD compared to SDI imply that the alternating wet-dry cycles of PRD, rather than simply a deficit irrigation, as in SDI, had a distinctive effect on growth, ripening and berry composition. Our data imply that these different responses might be related to ABA physiology, and especially to ABA levels in berries during ripening. [source] Conjugated polyamines and hydroxycinnamic acids in grape berries during Botrytis cinerea disease development: differences between ,noble rot' and ,grey mould'AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 2 2003L. GENY Abstract Data are provided on contrasting levels of different categories of polyamines and hydroxycinnamic acids during the course of disease development due to Botrytis cinerea on ripe grape berries that led to either noble rot or to grey mould. Noble rot development was mainly characterised by a greater accumulation of wall-bound polyamines at the beginning of infection, whereas the disease process that led to grey mould was marked by an increase of conjugated polyamines. During grey mould infection, coumaric acid was the predominant hydroxycinnamic acid present in both healthy and infected grape berries regardless of infection stage, whereas ferulic acid was present at lower concentrations than the other hydroxycinnamic acids identified. Moreover, changes in the relative proportions of each of the three hydroxycinnamic acids considered showed contrasting patterns according to the sort of rot which developed. The different roles of these compounds (hydroxycinnamic acids and polyamines) and their involvement in the interaction between Botrytis cinerea and grapevines is discussed. During development of grey mould, coumaric acid was the predominant hydroxycinnamic acid at the beginning and the end of infection, whereas caffeic acid predominated during mid stage. [source] Impact of water-dispersible beadlets as a vehicle for the delivery of carotenoids to cultured cellsBIOFACTORS, Issue 3-4 2002Siranoush Shahrzad Abstract Water-dispersible beadlets of carotenoids were used as supplements for human umbilical vein endothelial cells (HUVECs), human peripheral blood mononuclear cells (PBMCs) and human monocytes. Stability, cellular association and cytotoxicity of the carotenoid beadlets were compared with carotenoids delivered with tetrahydrofuran (THF). Incubations with lycopene, ,-carotene, lutein and astaxanthin dissolved in THF resulted in a lower stability in the medium, lower cellular association, and a higher standard deviation. Beadlets provided 60, 4, 6, and 2 times greater accumulation of lycopene, ,-carotene, lutein and astaxanthin, respectively, by PBMCs than THF. The cellular association of carotenoids delivered by THF seems to be more carotenoid-specific than when carotenoids are delivered by beadlets. After 48,h of incubation under cell culture conditions all of the four carotenoids (1 ,M) delivered by beadlets to the medium showed a reduction less than 30%. In addition, no cytotoxic effect of the carotenoid beadlets or the vehicle alone was detected in a concentration range of 0.5-5 ,M. The results show that beadlets are a non-toxic vehicle for supplementing and stabilizing carotenoids in culture media offering a reasonable compromise in term of cell accumulation efficiency. [source] Stereoselective disposition of fenoprofen in plasma and synovial fluid of patients with rheumathoid arthritisCHIRALITY, Issue 4 2007Carolina De Miranda Silva Abstract The simultaneous disposition of fenoprofen enantiomers in synovial fluid and plasma was studied in 11 patients with arthritis and chronic knee effusions treated with a single oral dose of 600 mg rac-fenoprofen. A plasma sample and a synovial fluid sample were collected simultaneously from each patient up to 16 h after the administration of fenoprofen. A stereospecific assay for fenoprofen using LC,MS,MS was developed and applied successfully to the analysis of the enantiomers in plasma (LOQ = 10 ng of each enantiomer/ml) and synovial fluid (LOQ = 25 ng of each enantiomer/ml). The values of the area under the curve (AUC) for the S -(+)-fenoprofen eutomer were ,2.5 times higher in plasma than in synovial fluid (256 vs 104 ,g h/ml), while the values for the R -(,)-fenoprofen distomer were about four times higher in plasma than in synovial fluid (42.5 vs 10.5 ,g h/ml). These data demonstrate accumulation of the S -(+)-fenoprofen eutomer in plasma and in synovial fluid, with concentrations versus time AUC (+)/(,) ratios of 6.0 in plasma and 9.9 in synovial fluid, suggesting a greater accumulation of the eutomer at the active site represented by synovial fluid than in plasma. This result demonstrates the importance of enantioselective methods and of analysis of synovial fluid rather than plasma in studies of the pharmacokinetics,pharmacodynamics of fenoprofen. Chirality, 2007. © 2007 Wiley-Liss, Inc. [source] | ||||||||||||||||