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Sample records for reduced invasive capacity

  1. Cancer-associated fibroblasts from human NSCLC survive ablative doses of radiation but their invasive capacity is reduced

    PubMed Central

    2012-01-01

    Background Cancer-Associated Fibroblasts (CAFs) are significant components of solid malignancies and play central roles in cancer sustainability, invasion and metastasis. In this study we have investigated the invasive capacity and matrix remodelling properties of human lung CAFs after exposure to ablative doses of ionizing radiation (AIR), equivalent to single fractions delivered by stereotactic ablative radiotherapy (SART) for medically inoperable stage-I/II non-small-cell lung cancers. Methods CAFs were isolated from lung tumour specimens from 16 donors. Initially, intrinsic radiosensitivity was evaluated by checking viability and extent of DNA-damage response (DDR) at different radiation doses. The migrative and invasive capacities of CAFs were thereafter determined after a sub-lethal single radiation dose of 18 Gy. To ascertain the mechanisms behind the altered invasive capacity of cells, expression of matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) were measured in the conditioned media several days post-irradiation, along with expression of cell surface integrins and dynamics of focal contacts by vinculin-staining. Results Exposing CAFs to 1 × 18 Gy resulted in a potent induction of multiple nuclear DDR foci (> 9/cell) with little resolution after 120 h, induced premature cellular senescence and inhibition of the proliferative, migrative and invasive capacity. AIR promoted MMP-3 and inhibited MMP-1 appearance to some extent, but did not affect expression of other major MMPs. Furthermore, surface expression of integrins α2, β1 and α5 was consistently enhanced, and a dramatic augmentation and redistribution of focal contacts was observed. Conclusions Our data indicate that ablative doses of radiation exert advantageous inhibitory effects on the proliferative, migratory and invasive capacity of lung CAFs. The reduced motility of irradiated CAFs might be a consequence of stabilized focal contacts via integrins. PMID:22500976

  2. Tree invasion effects on peat water storage capacity (La Guette peatland, France)

    NASA Astrophysics Data System (ADS)

    Binet, Stephane; Viel, Emelie; Gogo, Sebastien; Le Moing, Franck; Laggoun-Defarge, Fatima

    2015-04-01

    In peatlands, carbon fluxes are mainly controlled by peat water saturation state, and this saturation state is an equilibrium between recharge/drainage fluxes and the peat storage capacity. The invasion of Sphagnum peatlands by vascular plants is a current problem in many peat-accumulating systems, raising the question of the relationships between vegetation changes and water storage capacity of peat horizons. To investigate this question, the water storage capacity of the "La Guette" peatland (France), invaded by Betula spp was monitored at the watershed scale since 2008 using a water balance approach and was estimated during the 20th century using historical photographs showing the drainage network and the land cover change. During this period, the site clearly experienced a vegetation change as the site was treeless in 1944. Two main results arise from this experimental device: (1) In this disturbed peatland, tree consumption amplifies the summer drought and the resulting water table drawdown allows an increase of air entrapment in the peat. Even if runoff flows occurred after this drought, the water storage capacity is affected, with about 30% of air that remains trapped in the peat porosity 6 months after the drought period. The effects of a single drought on peat water storage capacity are observed over more than a single hydrological cycle, suggesting a possible cumulative effect of droughts decreasing the peat water storage capacity. (2) Tree invasion is found to drive the drainage network morphology. Hydrological model calibrated for the study site suggested that the development of drainage network had reduced the water storage capacity of the peatland. These observations evidenced a positive feedback between vegetation dynamics and water storage capacity: tree invasion changes the drainage network geometry that decreases the peat water storage capacity, which in return may favor tree development. These two results highlight that the peat water storage

  3. Serotype Specific Invasive Capacity and Persistent Reduction in Invasive Pneumococcal Disease

    PubMed Central

    Yildirim, Inci; Hanage, William P.; Lipsitch, Marc; Shea, Kimberly M.; Stevenson, Abbie; Finkelstein, Jonathan; Huang, Susan S.; Lee, Grace M.; Kleinman, Ken; Pelton, SI

    2011-01-01

    Defining the propensity of Streptoccocus pneumoniae (SP) serotypes to invade sterile body sites following nasopharyngeal (NP) acquisition has the potential to inform about how much invasive pneumococcal disease (IPD) may occur in a typical population with a given distribution of carriage serotypes. Data from enhanced surveillance for IPD in Massachusetts children ≤7 years in 2003/04, 2006/07 and 2008/09 seasons and surveillance of SP NP carriage during the corresponding respiratory seasons in 16 Massachusetts communities in 2003/04 and 8 of the 16 communities in both 2006/07 and 2008/09 were used to compute a serotype specific “invasive capacity (IC)” by dividing the incidence of IPD due to serotype x by the carriage prevalence of that same serotype in children of the same age. A total of 206 IPD and 806 NP isolates of SP were collected during the study period. An approximate 50-fold variation in the point estimates between the serotypes having the highest (18C, 33F, 7F, 19A, 3 and 22F) and lowest (6C, 23A, 35F, 11A, 35B, 19F, 15A, and 15BC) IC was observed. Point estimates of IC for most of the common serotypes currently colonizing children in Massachusetts were low and likely explain the continued reduction in IPD from the pre-PCV era in the absence of specific protection against these serotypes. Invasive capacity differs among serotypes and as new pneumococcal conjugate vaccines are introduced, ongoing surveillance will be essential to monitor whether serotypes with high invasive capacity emerge (e.g. 33F, 22F) as successful colonizers resulting in increased IPD incidence due to replacement serotypes. PMID:21029807

  4. Reducing the invasiveness of modelling frameworks

    NASA Astrophysics Data System (ADS)

    Donchyts, G.; Baart, F.

    2010-12-01

    There are several modelling frameworks available that allow for environmental models to exchange data with other models. Many efforts have been made in the past years promoting solutions aimed at integrating different numerical models with each other as well as at simplifying the way to set them up, entering the data, and running them. Meanwhile the development of many modeling frameworks concentrated on the interoperability of different model engines, several standards were introduced such as ESMF, OMS and OpenMI. One of the issues with applying modelling frameworks is the invasessness, the more the model has to know about the framework, the more intrussive it is. Another issue when applying modelling frameworks are that a lot of environmental models are written in procedural and in FORTRAN, which is one of the few languages that doesn't have a proper interface with other programming languages. Most modelling frameworks are written in object oriented languages like java/c# and the modelling framework in FORTRAN ESMF is also objected oriented. In this research we show how the application of domain driven, object oriented development techniques to environmental models can reduce the invasiveness of modelling frameworks. Our approach is based on four different steps: 1) application of OO techniques and reflection to the existing model to allow introspection. 2) programming language interoperability, between model written in a procedural programming language and modeling framework written in an object oriented programming language. 3) Domain mapping between data types used by model and other components being integrated 4) Connecting models using framework (wrapper) We compare coupling of an existing model as it was to the same model adapted using the four step approach. We connect both versions of the models using two different integrated modelling frameworks. As an example of a model we use the coastal morphological model XBeach. By adapting this model it allows for

  5. Positive association of long telomeres with the invasive capacity of hepatocellular carcinoma cells.

    PubMed

    Ko, Eunkyong; Jung, Guhung

    2014-05-01

    Invasion, the representative feature of malignant tumors, leads to an increase in mortality. The malignant liver tumor - hepatocellular carcinoma (HCC) - has an enhanced invasive capacity that results in increased patient mortality. Moreover, this enhanced invasive capacity is due to the up-regulation of invasion promoters such as zinc finger protein SNAI1 (Snail) and matrix metalloproteinases (MMPs), and the down-regulation of invasion suppressor molecules such as E-cadherin. Telomerase reverse transcriptase (TERT), which encodes the catalytic subunit of telomerase, is highly expressed in a variety of invasive cancers, including HCC. Telomerase activation induces telomere elongation, thereby leading to cell immortalization during malignant tumor progression. However, the relationship between telomere length and invasion is yet to be experimentally corroborated. In this paper, we revealed that invasive HCC cells passing through the Matrigel display significantly longer telomeres than non-invasive HCC cells. Moreover, we established a method that can distinguish and sort cells containing long telomeres and short telomeres. Using this system, we observed that the HCC cells containing long telomeres had a high-level expression of invasion-promoting genes and a low-level expression of invasion-suppressing E-cadherin. Furthermore, HCC cells containing long telomeres exhibited a higher invasive capacity than HCC cells containing short telomeres. Taken together, our findings suggest that long telomeres are positively associated with the invasive capacity of HCC cells and may be a potent target for malignant liver cancer treatment. PMID:24732358

  6. Core bit design reduces mud invasion, improves ROP

    SciTech Connect

    Clydesdale, G. ); Leseultre, A.; Lamine, E. )

    1994-08-08

    A recently developed core bit reduces fluid invasion in the cut core by minimizing the exposure to the drilling fluid and by increasing the rate of penetration (ROP). A high ROP during coring is one of the major factors in reducing mud filtrate invasion in cores. This new low-invasion polycrystalline diamond compact (PDC) core bit was designed to achieve a higher ROP than conventional PDC core bits without detriment to the cutting structure. The paper describes the bit and its operation, results of lab tests, fluid dynamics, and results of field tests.

  7. Global threats from invasive alien species in the twenty-first century and national response capacities.

    PubMed

    Early, Regan; Bradley, Bethany A; Dukes, Jeffrey S; Lawler, Joshua J; Olden, Julian D; Blumenthal, Dana M; Gonzalez, Patrick; Grosholz, Edwin D; Ibañez, Ines; Miller, Luke P; Sorte, Cascade J B; Tatem, Andrew J

    2016-01-01

    Invasive alien species (IAS) threaten human livelihoods and biodiversity globally. Increasing globalization facilitates IAS arrival, and environmental changes, including climate change, facilitate IAS establishment. Here we provide the first global, spatial analysis of the terrestrial threat from IAS in light of twenty-first century globalization and environmental change, and evaluate national capacities to prevent and manage species invasions. We find that one-sixth of the global land surface is highly vulnerable to invasion, including substantial areas in developing economies and biodiversity hotspots. The dominant invasion vectors differ between high-income countries (imports, particularly of plants and pets) and low-income countries (air travel). Uniting data on the causes of introduction and establishment can improve early-warning and eradication schemes. Most countries have limited capacity to act against invasions. In particular, we reveal a clear need for proactive invasion strategies in areas with high poverty levels, high biodiversity and low historical levels of invasion. PMID:27549569

  8. Global threats from invasive alien species in the twenty-first century and national response capacities

    PubMed Central

    Early, Regan; Bradley, Bethany A.; Dukes, Jeffrey S.; Lawler, Joshua J.; Olden, Julian D.; Blumenthal, Dana M.; Gonzalez, Patrick; Grosholz, Edwin D.; Ibañez, Ines; Miller, Luke P.; Sorte, Cascade J. B.; Tatem, Andrew J.

    2016-01-01

    Invasive alien species (IAS) threaten human livelihoods and biodiversity globally. Increasing globalization facilitates IAS arrival, and environmental changes, including climate change, facilitate IAS establishment. Here we provide the first global, spatial analysis of the terrestrial threat from IAS in light of twenty-first century globalization and environmental change, and evaluate national capacities to prevent and manage species invasions. We find that one-sixth of the global land surface is highly vulnerable to invasion, including substantial areas in developing economies and biodiversity hotspots. The dominant invasion vectors differ between high-income countries (imports, particularly of plants and pets) and low-income countries (air travel). Uniting data on the causes of introduction and establishment can improve early-warning and eradication schemes. Most countries have limited capacity to act against invasions. In particular, we reveal a clear need for proactive invasion strategies in areas with high poverty levels, high biodiversity and low historical levels of invasion. PMID:27549569

  9. Protosemiosis: agency with reduced representation capacity

    PubMed Central

    Sharov, Alexei A.; Vehkavaara, Tommi

    2014-01-01

    Life has semiotic nature; and as life forms differ in their complexity, functionality, and adaptability, we assume that forms of semiosis also vary accordingly. Here we propose a criterion to distinguish between the primitive kind of semiosis, which we call “protosemiosis” (following Prodi) from the advanced kind of semiosis, or “eusemiosis”. In protosemiosis, agents associate signs directly with actions without considering objects, whereas in eusemiosis, agents associate signs with objects and only then possibly with actions. Protosemiosis started from the origin of life, and eusemiosis started when evolving agents acquired the ability to track and classify objects. Eusemiosis is qualitatively different from protosemiosis because it can not be reduced to a small number of specific signaling pathways. Proto-signs can be classified into proto-icons that signal via single specific interaction, proto-indexes that combine several functions, and proto-symbols that are processed by a universal subagent equipped with a set of heritable adapters. Prefix “proto” is used here to characterize signs at the protosemiotic level. Although objects are not recognized by protosemiotic agents, they can be reliably reconstructed by human observers. In summary, protosemiosis is a primitive kind of semiosis that supports “know-how” without “know-what”. Without studying protosemiosis, the biosemiotics theory would be incomplete. PMID:25937852

  10. Investigating mechanisms of alkalinization for reducing primary breast tumor invasion.

    PubMed

    Robey, Ian F; Nesbit, Lance A

    2013-01-01

    The extracellular pH (pHe) of many solid tumors is acidic as a result of glycolytic metabolism and poor perfusion. Acidity promotes invasion and enhances metastatic potential. Tumor acidity can be buffered by systemic administration of an alkaline agent such as sodium bicarbonate. Tumor-bearing mice maintained on sodium bicarbonate drinking water exhibit fewer metastases and survive longer than untreated controls. We predict this effect is due to inhibition of tumor invasion. Reducing tumor invasion should result in fewer circulating tumor cells (CTCs). We report that bicarbonate-treated MDA-MB-231 tumor-bearing mice exhibited significantly lower numbers of CTCs than untreated mice (P < 0.01). Tumor pHe buffering may reduce optimal conditions for enzymes involved in tumor invasion such as cathepsins and matrix metalloproteases (MMPs). To address this, we tested the effect of transient alkalinization on cathepsin and MMP activity using enzyme activatable fluorescence agents in mice bearing MDA-MB-231 mammary xenografts. Transient alkalinization significantly reduced the fluorescent signal of protease-specific activatable agents in vivo (P ≤ 0.003). Alkalinization, however, did not affect expression of carbonic anhydrase IX (CAIX). The findings suggest a possible mechanism in a live model system for breast cancer where systemic alkalinization slows the rate of invasion. PMID:23936808

  11. Invasive lionfish reduce native fish abundance on a regional scale.

    PubMed

    Ballew, Nicholas G; Bacheler, Nathan M; Kellison, G Todd; Schueller, Amy M

    2016-01-01

    Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990-2014). Our results suggest that 1) lionfish-impacted areas off of the southeastern United States are most prevalent off-shore near the continental shelf-break but are also common near-shore and 2) in impacted areas, lionfish have reduced tomtate (a native forage fish) abundance by 45% since the invasion began. Tomtate served as a model native fish species in our analysis, and as such, it is likely that the lionfish invasion has had similar impacts on other species, some of which may be of economic importance. Barring the development of a control strategy that reverses the lionfish invasion, the abundance of lionfish in the Atlantic, Caribbean, and Gulf of Mexico will likely remain at or above current levels. Consequently, the effect of lionfish on native fish abundance will likely continue for the foreseeable future. PMID:27578096

  12. Invasive lionfish reduce native fish abundance on a regional scale

    PubMed Central

    Ballew, Nicholas G.; Bacheler, Nathan M.; Kellison, G. Todd; Schueller, Amy M.

    2016-01-01

    Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990–2014). Our results suggest that 1) lionfish-impacted areas off of the southeastern United States are most prevalent off-shore near the continental shelf-break but are also common near-shore and 2) in impacted areas, lionfish have reduced tomtate (a native forage fish) abundance by 45% since the invasion began. Tomtate served as a model native fish species in our analysis, and as such, it is likely that the lionfish invasion has had similar impacts on other species, some of which may be of economic importance. Barring the development of a control strategy that reverses the lionfish invasion, the abundance of lionfish in the Atlantic, Caribbean, and Gulf of Mexico will likely remain at or above current levels. Consequently, the effect of lionfish on native fish abundance will likely continue for the foreseeable future. PMID:27578096

  13. Are Vegetative Reproduction Capacities the Cause of Widespread Invasion of Eurasian Salicaceae in Patagonian River Landscapes?

    PubMed Central

    Thomas, Lisa K.; Tölle, Lena; Ziegenhagen, Birgit; Leyer, Ilona

    2012-01-01

    In recent decades, invasive willows and poplars (Salicaceae) have built dense floodplain forests along most of the rivers in Patagonia, Argentina. These invasion processes may affect Salix humboldtiana as the only native floodplain tree species in this region. It is assumed, that the property to reproduce vegetatively can play an important role in the establishment of invasive species in their new range. Thus, in order to contribute to a better understanding of willow and poplar invasions in riparian systems and to assess the potential impacts on S. humboldtiana the vegetative reproduction capacities of native and invasive Salicaceae were analysed. In a greenhouse experiment, we studied cutting survival and growth performance of the three most dominant invasive Salicaceae of the Patagonian Río Negro region (two Salix hybrids and Populus spec.), as well as S. humboldtiana, taking into account three different moisture and two different soil conditions. In a subsequent experiment, the shoot and root biomass of cuttings from the former experiment were removed and the bare cuttings were replanted to test their ability to re-sprout. The two invasive willow hybrids performed much better than S. humboldtiana and Populus spec. under all treatment combinations and tended to re-sprout more successfully after repeated biomass loss. Taking into account the ecology of vegetative and generative recruits of floodplain willows, the results indicate that the more vigorous vegetative reproduction capacity can be a crucial property for the success of invasive willow hybrids in Patagonia being a potential threat for S. humboldtiana. PMID:23226531

  14. Reduced genetic variation and the success of an invasive species

    PubMed Central

    Tsutsui, Neil D.; Suarez, Andrew V.; Holway, David A.; Case, Ted J.

    2000-01-01

    Despite the severe ecological and economic damage caused by introduced species, factors that allow invaders to become successful often remain elusive. Of invasive taxa, ants are among the most widespread and harmful. Highly invasive ants are often unicolonial, forming supercolonies in which workers and queens mix freely among physically separate nests. By reducing costs associated with territoriality, unicolonial species can attain high worker densities, allowing them to achieve interspecific dominance. Here we examine the behavior and population genetics of the invasive Argentine ant (Linepithema humile) in its native and introduced ranges, and we provide a mechanism to explain its success as an invader. Using microsatellite markers, we show that a population bottleneck has reduced the genetic diversity of introduced populations. This loss is associated with reduced intraspecific aggression among spatially separate nests, and leads to the formation of interspecifically dominant supercolonies. In contrast, native populations are more genetically variable and exhibit pronounced intraspecific aggression. Although reductions in genetic diversity are generally considered detrimental, these findings provide an example of how a genetic bottleneck can lead to widespread ecological success. In addition, these results provide insights into the origin and evolution of unicoloniality, which is often considered a challenge to kin selection theory. PMID:10811892

  15. Does high biodiversity reduce the risk of Lyme disease invasion?

    PubMed Central

    2013-01-01

    Background It has been suggested that increasing biodiversity, specifically host diversity, reduces pathogen and parasite transmission amongst wildlife (causing a “dilution effect”), whereby transmission amongst efficient reservoir hosts, (e.g. Peromyscus spp. mice for the agent of Lyme disease Borrelia burgdorferi) is reduced by the presence of other less efficient host species. If so, then increasing biodiversity should inhibit pathogen and parasite invasion. Methods We investigated this hypothesis by studying invasion of B. burgdorferi and its tick vector Ixodes scapularis in 71 field sites in southeastern Canada. Indices of trapped rodent host diversity, and of biodiversity of the wider community, were investigated as variables explaining the numbers of I. scapularis collected and B. burgdorferi infection in these ticks. A wide range of alternative environmental explanatory variables were also considered. Results The observation of low I. scapularis abundance and low B. burgdorferi infection prevalence in sites where I. scapularis were detected was consistent with early-stage invasion of the vector. There were significant associations between the abundance of ticks and season, year of study and ambient temperature. Abundance of host-seeking larvae was significantly associated with deer density, and abundance of host-seeking larvae and nymphs were positively associated with litter layer depth. Larval host infestations were lower where the relative proportion of non-Peromyscus spp. was high. Infestations of hosts with nymphs were lower when host species richness was higher, but overall nymphal abundance increased with species richness because Peromyscus spp. mouse abundance and host species richness were positively correlated. Nymphal infestations of hosts were lower where tree species richness was higher. B. burgdorferi infection prevalence in ticks varied significantly with an index of rates of migratory bird-borne vector and pathogen invasion. Conclusions

  16. Reduced visual processing capacity in sleep deprived persons.

    PubMed

    Kong, Danyang; Soon, Chun Siong; Chee, Michael W L

    2011-03-15

    Multiple experiments have found sleep deprivation to lower task-related parietal and extrastriate visual activation, suggesting a reduction of visual processing capacity in this state. The perceptual load theory of attention (Lavie, 1995) predicts that our capacity to process unattended distractors will be reduced by increasing perceptual difficulty of task-relevant stimuli. Here, we evaluated the effects of sleep deprivation and perceptual load on visual processing capacity by measuring neural repetition-suppression to unattended scenes while healthy volunteers attended to faces embedded in face-scene pictures. Perceptual load did not affect repetition suppression after a normal night of sleep. Sleep deprivation reduced repetition suppression in the parahippocampal place area (PPA) in the high but not low perceptual load condition. Additionally, the extent to which task-related fusiform face area (FFA) activation was reduced after sleep deprivation correlated with behavioral performance and lowered repetition suppression in the PPA. The findings concerning correct responses indicate that a portion of stimulus related activation following a normal night of sleep contributes to potentially useful visual processing capacity that is attenuated following sleep deprivation. Finally, when unattended stimuli are not highly intrusive, sleep deprivation does not appear to increase distractibility. PMID:21195190

  17. In vitro invasive capacity of Salmonella strains into sections of the layer hen oviduct.

    PubMed

    McWhorter, Andrea R; Chousalkar, Kapil K

    2016-08-30

    Raw or undercooked eggs and egg products are frequently identified as the source of Salmonella following outbreaks of foodborne gastrointestinal disease. Some Salmonella serovars, such as Salmonella Enteriditis, have a high tropism for the oviduct of laying hens. Oviduct colonization with S. Enteriditis can result in both internal and external contamination of an egg. While oviduct invasion is not limited to S. Enteriditis, the invasive capacities of other serovars is not widely known. In this study, the in vitro invasive ability of eighteen Salmonella isolates of representative serovars into different segments of the oviduct was assessed. All Salmonella isolates tested were invasive and the highest bacterial invasion was observed in segments of the isthmus and vagina. S. Bredeney consistently exhibited the lowest invasion into all sections of the oviduct. Interestingly, the S. Typhimurium definitive types included in this study did not exhibit significantly greater invasion capacity than other serovars. In this study, the genomic capacity of the selected isolates of representative Salmonella serovars to colonize the layer hen oviduct was also investigated. Previous studies have identified several genes upregulated during oviduct colonization by S. Enteriditis. Single gene comparison of 107 genes from eleven Salmonella isolates was conducted to determine whether these oviduct colonization genes were present within each bacterial genome. The degree of homology with corresponding sequences in S. Enteriditis P125109 was also determined for each gene. Genes encoding the O-antigen as well as phage and virulence plasmid genes were among the most highly variable and may serve specific roles in oviduct invasion. PMID:27527775

  18. Soil biota reduce allelopathic effects of the invasive Eupatorium adenophorum.

    PubMed

    Zhu, Xunzhi; Zhang, Jintun; Ma, Keping

    2011-01-01

    Allelopathy has been hypothesized to play a role in exotic plant invasions, and study of this process can improve our understanding of how direct and indirect plant interactions influence plant community organization and ecosystem functioning. However, allelopathic effects can be highly conditional. For example allelopathic effects demonstrated in vivo can be difficult to demonstrate in field soils. Here we tested phytotoxicity of Eupatorium adenophorum (croftonweed), one of the most destructive exotic species in China, to a native plant species Brassica rapa both in sand and in native soil. Our results suggested that natural soils from different invaded habitats alleviated or eliminated the efficacy of potential allelochemicals relative to sand cultures. When that soil is sterilized, the allelopathic effects returned; suggesting that soil biota were responsible for the reduced phytotoxicity in natural soils. Neither of the two allelopathic compounds (9-Oxo-10,11-dehydroageraphorone and 9b-Hydroxyageraphorone) of E. adenophorum could be found in natural soils infested by the invader, and when those compounds were added to the soils as leachates, they showed substantial degradation after 24 hours in natural soils but not in sand. Our findings emphasize that soil biota can reduce the allelopathic effects of invaders on other plants, and therefore can reduce community invasibility. These results also suggest that soil biota may have stronger or weaker effects on allelopathic interactions depending on how allelochemicals are delivered. PMID:21980442

  19. Reducing proactive aggression through non-invasive brain stimulation.

    PubMed

    Dambacher, Franziska; Schuhmann, Teresa; Lobbestael, Jill; Arntz, Arnoud; Brugman, Suzanne; Sack, Alexander T

    2015-10-01

    Aggressive behavior poses a threat to human collaboration and social safety. It is of utmost importance to identify the functional mechanisms underlying aggression and to develop potential interventions capable of reducing dysfunctional aggressive behavior already at a brain level. We here experimentally shifted fronto-cortical asymmetry to manipulate the underlying motivational emotional states in both male and female participants while assessing the behavioral effects on proactive and reactive aggression. Thirty-two healthy volunteers received either anodal transcranial direct current stimulation to increase neural activity within right dorsolateral prefrontal cortex, or sham stimulation. Aggressive behavior was measured with the Taylor Aggression Paradigm. We revealed a general gender effect, showing that men displayed more behavioral aggression than women. After the induction of right fronto-hemispheric dominance, proactive aggression was reduced in men. This study demonstrates that non-invasive brain stimulation can reduce aggression in men. This is a relevant and promising step to better understand how cortical brain states connect to impulsive actions and to examine the causal role of the prefrontal cortex in aggression. Ultimately, such findings could help to examine whether the brain can be a direct target for potential supportive interventions in clinical settings dealing with overly aggressive patients and/or violent offenders. PMID:25680991

  20. RhoC is essential for TGF-{beta}1-induced invasive capacity of rat ascites hepatoma cells

    SciTech Connect

    Mukai, M.; Endo, H.; Iwasaki, T.; Tatsuta, M.; Togawa, A.; Nakamura, H.; Inoue, M. . E-mail: inoue-ma2@mc.pref.osaka.jp

    2006-07-21

    Transforming growth factor-{beta}1 (TGF-{beta}1) is a multifunctional growth factor that plays a role in cell proliferation, differentiation, extracellular matrix production, apoptosis, and cell motility. We show here that TGF-{beta}1 increased the invasiveness of MM1 cells, which are a highly invasive clone of rat ascites hepatoma cells. Both mRNA and protein levels of RhoC but not RhoA in TGF-{beta}1-treated MM1 cells increased. In parallel with this increase in expression, RhoC activity was induced by TGF-{beta}1 treatment. When RhoC was overexpressed in MM1 cells, the invasive capacity increased. The RhoC-overexpressing cells formed more nodules than did mock cells when injected into rat peritoneum. Furthermore, when RhoC expression was reduced by transfection with shRNA/RhoC, the invasiveness of MM1 cells decreased with concomitant suppression of RhoC expression. Thus, the induced expression of RhoC by TGF-{beta}1 in MM1 cells plays a critical role in TGF-{beta}1-induced cell migration.

  1. SNAIL transcription factor increases the motility and invasive capacity of prostate cancer cells

    PubMed Central

    OSORIO, LUIS A.; FARFÁN, NANCY M.; CASTELLÓN, ENRIQUE A.; CONTRERAS, HÉCTOR R.

    2016-01-01

    The incidence and mortality rates of prostate cancer (PCa) are increasing, and PCa is almost the second-leading cause of cancer-associated mortality in men. During tumor progression, epithelial cells decrease the number of adhesion molecules, change their polarity and position, rearrange their cytoskeleton and increase their migratory and invasive capacities. These changes are known under the concept of epithelial-mesenchymal transition (EMT). EMT is characterized by an upregulation of certain transcription factors, including SNAIL1, which represses genes that are characteristic of an epithelial phenotype, including E-cadherin, and indirectly increase the expression levels of genes, which are associated with the mesenchymal phenotype. It has been suggested that the transcription factor, SNAIL1, decreases the proliferation and increases the migratory and invasive capacities of PCa cell lines. The present study was performed using LNCaP and PC3 cell lines, in which the expression levels of SNAIL1 were increased or silenced through the use of lentiviral vectors. The expression levels of EMT markers were quantified using reverse transcription-quantitative polymerase chain reaction and western blot analysis. In addition, cell survival was analyzed using an MTS assay; cell proliferation was examined using an antibody targeting Ki-67; migration on plates with 8 µm pores to allow the passage of cells; and invasiveness was analyzed using a membrane chamber covered in dried basement membrane matrix solution. The levels of apoptosis were determined using a Caspase 3/7 assay containing a substrate modified by caspases 3 and 7. The results demonstrated that the overexpression and silencing of SNAIL1 decreased cell proliferation and survival. However, the overexpression of SNAIL1 decreased apoptosis, compared with cells with the SNAIL1-silenced cells, in which cell apoptosis increased. The migration and invasive capacities increased in the cells overexpressing SNAIL1, and

  2. SNAIL transcription factor increases the motility and invasive capacity of prostate cancer cells.

    PubMed

    Osorio, Luis A; Farfán, Nancy M; Castellón, Enrique A; Contreras, Héctor R

    2016-01-01

    The incidence and mortality rates of prostate cancer (PCa) are increasing, and PCa is almost the second‑leading cause of cancer‑associated mortality in men. During tumor progression, epithelial cells decrease the number of adhesion molecules, change their polarity and position, rearrange their cytoskeleton and increase their migratory and invasive capacities. These changes are known under the concept of epithelial‑mesenchymal transition (EMT). EMT is characterized by an upregulation of certain transcription factors, including SNAIL1, which represses genes that are characteristic of an epithelial phenotype, including E‑cadherin, and indirectly increase the expression levels of genes, which are associated with the mesenchymal phenotype. It has been suggested that the transcription factor, SNAIL1, decreases the proliferation and increases the migratory and invasive capacities of PCa cell lines. The present study was performed using LNCaP and PC3 cell lines, in which the expression levels of SNAIL1 were increased or silenced through the use of lentiviral vectors. The expression levels of EMT markers were quantified using reverse transcription‑quantitative polymerase chain reaction and western blot analysis. In addition, cell survival was analyzed using an MTS assay; cell proliferation was examined using an antibody targeting Ki‑67; migration on plates with 8 µm pores to allow the passage of cells; and invasiveness was analyzed using a membrane chamber covered in dried basement membrane matrix solution. The levels of apoptosis were determined using a Caspase 3/7 assay containing a substrate modified by caspases 3 and 7. The results demonstrated that the overexpression and silencing of SNAIL1 decreased cell proliferation and survival. However, the overexpression of SNAIL1 decreased apoptosis, compared with cells with the SNAIL1‑silenced cells, in which cell apoptosis increased. The migration and invasive capacities increased in the cells overexpressing

  3. Baicalein Reduces the Invasion of Glioma Cells via Reducing the Activity of p38 Signaling Pathway

    PubMed Central

    Lei, Xiaoming; Li, Siyuan; Zhang, Yong; Meng, Lihua; Xue, Rongliang; Li, Zongfang

    2014-01-01

    Baicalein, one of the major flavonids in Scutellaria baicalensis, has historically been used in anti-inflammatory and anti-cancer therapies. However, the anti-metastatic effect and related mechanism(s) in glioma are still unclear. In this study, we thus utilized glioma cell lines U87MG and U251MG to explore the effect of baicalein. We found that administration of baicalein significantly inhibited migration and invasion of glioma cells. In addition, after treating with baicalein for 24 h, there was a decrease in the levels of matrix metalloproteinase-2 (MMP-2) and MMP-9 expression as well as proteinase activity in glioma cells. Conversely, the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 was increased in a dose-dependent manner. Moreover, baicalein treatment significantly decreased the phosphorylated level of p38, but not ERK1/2, JNK1/2 and PI3K/Akt. Combined treatment with a p38 inhibitor (SB203580) and baicalein resulted in the synergistic reduction of MMP-2 and MMP-9 expression and then increase of TIMP-1 and TIMP-2 expression; and the invasive capabilities of U87MG cells were also inhibited. However, p38 chemical activator (anisomycin) could block these effects produced by baicalein, suggesting baicalein directly downregulate the p38 signaling pathway. In conclusion, baicalein inhibits glioma cells invasion and metastasis by reducing cell motility and migration via suppression of p38 signaling pathway, suggesting that baicalein is a potential therapeutic agent for glioma. PMID:24587321

  4. Mesenchymal stem cells from osteoporotic patients reveal reduced migration and invasion upon stimulation with BMP-2 or BMP-7.

    PubMed

    Haasters, Florian; Docheva, Denitsa; Gassner, Christoph; Popov, Cvetan; Böcker, Wolfgang; Mutschler, Wolf; Schieker, Matthias; Prall, Wolf Christian

    2014-09-12

    Fractures to the osteoporotic bone feature a delay in callus formation and reduced enchondral ossification. Human mesenchymal stem cells (hMSC), the cellular source of fracture healing, are recruited to the fracture site by cytokines, such as BMP-2 and BMP-7. Aim of the study was to scrutinize hMSC for osteoporosis associated alterations in BMP mediated migration and invasion as well as in extracellular matrix (ECM) binding integrin expression. HMSC were isolated from 18 healthy or osteoporotic donors. Migration was assessed using a collagen IV coated micro-slide linear gradient chamber and time-lapse microscopy. Invasion was analyzed utilizing an ECM coated transmembrane invasion assay. Quantitative real-time RT PCR was performed for the ECM binding integrins α1, α2, α3, α4, α5, α11, αv and β1. HMSC from osteoporotic patients showed a significant increase of migration upon BMP-2 or FCS stimulation, as well as a significant increase of invasion upon BMP-2, BMP-7 or FCS stimulation. Nevertheless, the migration and invasion capacity was significantly decreased compared to healthy controls. Out of all integrins analyzed, collagen binding integrin α2 was significantly downregulated in hMSC from osteoporotic patients. In conclusion, we here demonstrate for the first time osteoporosis associated alterations in BMP mediated hMSC recruitment. These findings may underlie the reduced healing of osteoporotic fractures. Nevertheless, the maintained migration and invasion response upon BMP stimulation illustrates the therapeutic potential of these clinically approved substances in the treatment of osteoporotic fractures. Another therapeutic target may be the downregulation of the collagen binding integrin α2 in hMSC from osteoporotic patients. PMID:25152406

  5. Does seeding after wildfires in rangelands reduce erosion or invasive species?

    USGS Publications Warehouse

    Pyke, David A.; Wirth, Troy A.; Beyers, Jan L.

    2013-01-01

    Mitigation of ecological damage caused by rangeland wildfires has historically been an issue restricted to the western United States. It has focused on conservation of ecosystem function through reducing soil erosion and spread of invasive plants. Effectiveness of mitigation treatments has been debated recently. We reviewed recent literature to conduct a meta-analysis of seeding after wildfires to determine if seedings may (1) protect ecosystems against soil erosion and (2) reduce invasion or abundance of undesirable nonnative plant species. Effectiveness of postfire seedings was examined in 8 erosion and 19 invasive species cases. Seeding has little effect on erosion during the first year after fire and is highly dependent upon initial establishment and coverage of species in successive years. Among all seeding cases, 28% reduced, 67% were neutral, and 5% increased invasive species abundance. Older seedings were more likely to show reductions in invasives than younger seedings. Seedings with high plant establishment were more likely to reduce invasives than those with low establishment. Studies are needed that examine (1) frequency of adequate establishment of postfire seedings and causal factors of success or failure, (2) long-term impacts of seeding along a range of initial establishment and concomitant plant coverage over time as it relates to erosion and abundance of invasive plant species, and (3) auxiliary treatments designed to increase likelihood of germination and establishment given the inevitable variability of environmental conditions. These studies would aid land managers in deciding when postfire treatments are required and their likely level of success.

  6. Serum-Induced Differentiation of Glioblastoma Neurospheres Leads to Enhanced Migration/Invasion Capacity That Is Associated with Increased MMP9

    PubMed Central

    Joseph, Justin V.; Tomar, Tushar; Conroy, Siobhan; Eggens-Meijer, Ellie; Peñaranda Fajardo, Natalia; Pore, Milind M.; Balasubramanyian, Veerakumar; Wagemakers, Michiel; Copray, Sjef; den Dunnen, Wilfred F. A.; Kruyt, Frank A. E.

    2015-01-01

    Glioblastoma (GBM) is a highly infiltrative brain tumor in which cells with properties of stem cells, called glioblastoma stem cells (GSCs), have been identified. In general, the dominant view is that GSCs are responsible for the initiation, progression, invasion and recurrence of this tumor. In this study, we addressed the question whether the differentiation status of GBM cells is associated with their invasive capacity. For this, several primary GBM cell lines were used, cultured either as neurospheres known to enrich for GSCs or in medium supplemented with 10% FCS that promotes differentiation. The differentiation state of the cells was confirmed by determining the expression of stem cell and differentiation markers. The migration/invasion potential of these cells was tested using in vitro assays and intracranial mouse models. Interestingly, we found that serum-induced differentiation enhanced the invasive potential of GBM cells, which was associated with enhanced MMP9 expression. Chemical inhibition of MMP9 significantly reduced the invasive potential of differentiated cells in vitro. Furthermore, the serum-differentiated cells could revert back to an undifferentiated/stem cell state that were able to form neurospheres, although with a reduced efficiency as compared to non-differentiated counterparts. We propose a model in which activation of the differentiation program in GBM cells enhances their infiltrative potential and that depending on microenvironmental cues a significant portion of these cells are able to revert back to an undifferentiated state with enhanced tumorigenic potential. Thus, effective therapy should target both GSCs and differentiated offspring and targeting of differentiation-associated pathways may offer therapeutic opportunities to reduce invasive growth of GBM. PMID:26700636

  7. Structural basis for reduced glomerular filtration capacity in nephrotic humans.

    PubMed Central

    Drumond, M C; Kristal, B; Myers, B D; Deen, W M

    1994-01-01

    Previous studies have established that in a variety of human glomerulopathies the reduced glomerular filtration rate (GFR) is due to a marked lowering of the ultrafiltration coefficient (Kf). To identify the factors which lower Kf, we measured the filtering surface area per glomerulus, filtration slit frequency, basement membrane thickness, and GFR and its determinants in patients with minimal change and membraneous nephropathies and in age-matched healthy controls. Overall values of Kf for the two kidneys were calculated from GFR, renal plasma flow rate, systemic colloid osmotic pressure, and three assumed values for the transcapillary pressure difference. "Experimental" values of the glomerular hydraulic permeability (kexp) were then calculated from Kf, glomerular filtering surface area, and estimates of the total number of nephrons of the two kidneys. Independent estimates of the glomerular hydraulic permeability (kmodel) were obtained using a recent mathematical model that is based on analyses of viscous flow through the various structural components of the glomerular capillary wall. Individual values of basement membrane thickness and filtration slit frequency were used as inputs in this model. The results indicate that the reductions of Kf in both nephropathies can be attributed entirely to reduced glomerular hydraulic permeability. The mean values of kexp and kmodel were very similar in both disorders and much smaller in the nephrotic groups than in healthy controls. There was good agreement between kexp and kmodel for any given group of subjects. It was shown that, in both groups of nephrotics, filtration slit frequency was a more important determinant of the water flow resistance than was basement membrane thickness. The decrease in filtration slit frequency observed in both disorders caused the average path length for the filtrate to increase, thereby explaining the decreased hydraulic permeability. Images PMID:8083359

  8. The motile and invasive capacity of human endometrial stromal cells: implications for normal and impaired reproductive function.

    PubMed

    Weimar, Charlotte H E; Macklon, Nick S; Post Uiterweer, Emiel D; Brosens, Jan J; Gellersen, Birgit

    2013-01-01

    BACKGROUND Mechanisms underlying early reproductive loss in the human are beginning to be elucidated. The migratory and invasive capacity of human endometrial stromal cells (ESCs) is increasingly recognized to contribute to the intense tissue remodelling associated with embryo implantation, trophoblast invasion and endometrial regeneration. In this review, we examine the signals and mechanisms that control ESC migration and invasion and assess how deregulation of these cell functions contributes to common reproductive disorders. METHODS The PubMed database was searched for publications on motility and invasiveness of human ESCs in normal endometrial function and in reproductive disorders including implantation failure, recurrent pregnancy loss (RPL), endometriosis and adenomyosis, covering the period 2000-2012. RESULTS Increasing evidence suggests that implantation failure and RPL involve abnormal migratory responses of decidualizing ESCs to embryo and trophoblast signals. Numerous reports indicate that endometriosis, as well as adenomyosis, is associated with increased basal and stimulated invasiveness of ESCs and their progenitor cells, suggesting a link between a heightened menstrual repair response and the formation of ectopic implants. Migration and invasiveness of ESCs are controlled by a complex array of hormones, growth factors, chemokines and inflammatory mediators, and involve signalling through Rho GTPases, phosphatidylinositol-3-kinase and mitogen-activated protein kinase pathways. CONCLUSIONS Novel concepts are extending our understanding of the key functions of ESCs in effecting tissue repair imposed by cyclic menstruation and parturition. Migration of decidualizing ESCs also serves to support blastocyst implantation and embryo selection through discriminate motile responses directed by embryo quality. Targeting regulatory molecules holds promise for developing new strategies for the treatment of reproductive disorders such as endometriosis and

  9. Reducing capacities and redox potentials of humic substances extracted from sewage sludge.

    PubMed

    Yang, Zhen; Du, Mengchan; Jiang, Jie

    2016-02-01

    Humic substances (HS) are redox active organic materials that can be extracted from sewage sludge generated in wastewater treatment processes. Due to the poor understanding of reducing capacity, redox potentials and redox active functional groups of HS in sewage sludge, the potential contribution of sludge HS in transformation of wastewater contaminants is unclear. In the present study, the number of electrons donated or accepted by sewage sludge HS were quantified before and after reduction by iron compounds that possess different redox potentials and defined as the reducing capacity of the sewage sludge. In contrast to previous studies of soil and commercial humic acids (HA), reduced sludge HA showed a lower reducing capacity than that of native HA, which implies formation of semiquinone radicals since the semiquinone radical/hydroquinone pair has a much higher redox potential than the quinone/hydroquinone pair. It is novel that reducing capacities of sludge HA were determined in the redox potential range from -314 to 430 mV. The formation of semiquinone radicals formed during the reduction of quinone moieties in sludge HA is shown by three-dimensional excitation/emission matrix fluorescence spectroscopies information, increasing fluorescence intensities and blue-shifting of the excitation/emission peak of reduced sludge HA. Knowledge of sludge HS redox potentials and corresponding reducing capacities makes it possible to predict the transformation of redox active pollutants and facilitate manipulation and optimization of sludge loading wastewater treatment processes. PMID:26432531

  10. Carbon Addition Interacts with Water Availability to Reduce Invasive Forb Establishment in a Semi-arid Grassland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increases in nitrogen (N) availability can favor fast-growing invasive species over slow-growing native species. One way to reduce N availability is to add labile C to the soil, which can lead to microbial immobilization of plant available N, and reduce the success of invasive species. This method h...

  11. Factors affecting flight capacity and invasive characteristics of brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brown marmorated stink bug, Halyomorpha halys (Stål) is a highly destructive invasive pest of annual and perennial crops in the eastern United States and is an increasing threat to agriculture in the Pacific Northwest. In Oregon, this pest has become common in urban areas interspersed among high-val...

  12. Reducing capacity fade in vanadium redox flow batteries by altering charging and discharging currents

    NASA Astrophysics Data System (ADS)

    Agar, Ertan; Benjamin, A.; Dennison, C. R.; Chen, D.; Hickner, M. A.; Kumbur, E. C.

    2014-01-01

    In this study, the operation of a vanadium redox flow battery (VRFB) under asymmetric current conditions (i.e., different current densities during charge and discharge) was investigated as a technique to reduce its capacity loss. Two different membrane types (a convection-dominated membrane and a diffusion-dominated membrane) were analyzed. In these analyses, the charging current density was varied while the discharging current was held constant. For both membranes, it was found that increasing the charging current decreases the net convective crossover of vanadium ions, which reduces the capacity loss of the battery. When the tested membranes were compared, the improvement in capacity retention was found to be larger for the diffusion-dominated membrane (12.4%) as compared to the convection-dominated membrane (7.1%). The higher capacity retention in the diffusion-dominated membrane was attributed to the reduction in the cycling time (and hence, suppressed contribution of diffusion) due to the increased charging current. While asymmetric current operation helps reduce capacity loss, it comes at the expense of a reduction in the voltage efficiencies. Increasing the charging current was found to increase the ohmic losses, which lead to a decrease of 6% and 4.3% in the voltage efficiencies of the convection-dominated and diffusion-dominated membranes, respectively.

  13. Incentivizing the public to support invasive species management: eurasian milfoil reduces lakefront property values.

    PubMed

    Olden, Julian D; Tamayo, Mariana

    2014-01-01

    Economic evaluations of invasive species are essential for providing comprehensive assessments of the benefits and costs of publicly-funded management activities, yet many previous investigations have focused narrowly on expenditures to control spread and infestation. We use hedonic modeling to evaluate the economic effects of Eurasian milfoil (Myriophyllum spicatum) invasions on lakefront property values of single-family homes in an urban-suburban landscape. Milfoil often forms dense canopies at the water surface, diminishing the value of ecosystem services (e.g., recreation, fishing) and necessitating expensive control and management efforts. We compare 1,258 lakeshore property sale transactions (1995-2006) in 17 lakes with milfoil and 24 un-invaded lakes in King County, Washington (USA). After accounting for structural (e.g., house size), locational (e.g., boat launch), and environmental characteristics (e.g., water clarity) of lakes, we found that milfoil has a significant negative effect on property sales price ($94,385 USD lower price), corresponding to a 19% decline in mean property values. The aggregate cost of milfoil invading one additional lake in the study area is, on average, $377,542 USD per year. Our study illustrates that invasive aquatic plants can significantly impact property values (and associated losses in property taxes that reduce local government revenue), justifying the need for management strategies that prevent and control invasions. We recommend coordinated efforts across Lake Management Districts to focus institutional support, funding, and outreach to prevent the introduction and spread of milfoil. This effort will limit opportunities for re-introduction from neighboring lakes and incentivize private landowners and natural resource agencies to commit time and funding to invasive species management. PMID:25333619

  14. Incentivizing the Public to Support Invasive Species Management: Eurasian Milfoil Reduces Lakefront Property Values

    PubMed Central

    Olden, Julian D.; Tamayo, Mariana

    2014-01-01

    Economic evaluations of invasive species are essential for providing comprehensive assessments of the benefits and costs of publicly-funded management activities, yet many previous investigations have focused narrowly on expenditures to control spread and infestation. We use hedonic modeling to evaluate the economic effects of Eurasian milfoil (Myriophyllum spicatum) invasions on lakefront property values of single-family homes in an urban-suburban landscape. Milfoil often forms dense canopies at the water surface, diminishing the value of ecosystem services (e.g., recreation, fishing) and necessitating expensive control and management efforts. We compare 1,258 lakeshore property sale transactions (1995–2006) in 17 lakes with milfoil and 24 un-invaded lakes in King County, Washington (USA). After accounting for structural (e.g., house size), locational (e.g., boat launch), and environmental characteristics (e.g., water clarity) of lakes, we found that milfoil has a significant negative effect on property sales price ($94,385 USD lower price), corresponding to a 19% decline in mean property values. The aggregate cost of milfoil invading one additional lake in the study area is, on average, $377,542 USD per year. Our study illustrates that invasive aquatic plants can significantly impact property values (and associated losses in property taxes that reduce local government revenue), justifying the need for management strategies that prevent and control invasions. We recommend coordinated efforts across Lake Management Districts to focus institutional support, funding, and outreach to prevent the introduction and spread of milfoil. This effort will limit opportunities for re-introduction from neighboring lakes and incentivize private landowners and natural resource agencies to commit time and funding to invasive species management. PMID:25333619

  15. Competition from native hydrophytes reduces establishment and growth of invasive dense-flowered cordgrass (Spartina densiflora)

    PubMed Central

    Abbas, Ahmed M.; Rubio-Casal, Alfredo E.; De Cires, Alfonso; Figueroa, Enrique M.; Castillo, Jesús M.

    2015-01-01

    Experimental studies to determine the nature of ecological interactions between invasive and native species are necessary for conserving and restoring native species in impacted habitats. Theory predicts that species boundaries along environmental gradients are determined by physical factors in stressful environments and by competitive ability in benign environments, but little is known about the mechanisms by which hydrophytes exclude halophytes and the life history stage at which these mechanisms are able to operate. The ongoing invasion of the South American Spartina densiflora in European marshes is causing concern about potential impacts to native plants along the marsh salinity gradient, offering an opportunity to evaluate the mechanisms by which native hydrophytes may limit, or even prevent, the expansion of invasive halophytes. Our study compared S. densiflora seedling establishment with and without competition with Phragmites australis and Typha domingensis, two hydrophytes differing in clonal architecture. We hypothesized that seedlings of the stress tolerant S. densiflora would be out-competed by stands of P. australis and T. domingensis. Growth, survivorship, biomass patterns and foliar nutrient content were recorded in a common garden experiment to determine the effect of mature P. australis and T. domingensis on the growth and colonization of S. densiflora under fresh water conditions where invasion events are likely to occur. Mature P. australis stands prevented establishment of S. densiflora seedlings and T. domingensis reduced S. densiflora establishment by 38%. Seedlings grown with P. australis produced fewer than five short shoots and all plants died after ca. 2 yrs. Our results showed that direct competition, most likely for subterranean resources, was responsible for decreased growth rate and survivorship of S. densiflora. The presence of healthy stands of P. australis, and to some extent T. domingensis, along river channels and in brackish

  16. Competition from native hydrophytes reduces establishment and growth of invasive dense-flowered cordgrass (Spartina densiflora).

    PubMed

    Abbas, Ahmed M; Lambert, Adam M; Rubio-Casal, Alfredo E; De Cires, Alfonso; Figueroa, Enrique M; Castillo, Jesús M

    2015-01-01

    Experimental studies to determine the nature of ecological interactions between invasive and native species are necessary for conserving and restoring native species in impacted habitats. Theory predicts that species boundaries along environmental gradients are determined by physical factors in stressful environments and by competitive ability in benign environments, but little is known about the mechanisms by which hydrophytes exclude halophytes and the life history stage at which these mechanisms are able to operate. The ongoing invasion of the South American Spartina densiflora in European marshes is causing concern about potential impacts to native plants along the marsh salinity gradient, offering an opportunity to evaluate the mechanisms by which native hydrophytes may limit, or even prevent, the expansion of invasive halophytes. Our study compared S. densiflora seedling establishment with and without competition with Phragmites australis and Typha domingensis, two hydrophytes differing in clonal architecture. We hypothesized that seedlings of the stress tolerant S. densiflora would be out-competed by stands of P. australis and T. domingensis. Growth, survivorship, biomass patterns and foliar nutrient content were recorded in a common garden experiment to determine the effect of mature P. australis and T. domingensis on the growth and colonization of S. densiflora under fresh water conditions where invasion events are likely to occur. Mature P. australis stands prevented establishment of S. densiflora seedlings and T. domingensis reduced S. densiflora establishment by 38%. Seedlings grown with P. australis produced fewer than five short shoots and all plants died after ca. 2 yrs. Our results showed that direct competition, most likely for subterranean resources, was responsible for decreased growth rate and survivorship of S. densiflora. The presence of healthy stands of P. australis, and to some extent T. domingensis, along river channels and in brackish

  17. Differential tolerance capacity to unfavourable low and high temperatures between two invasive whiteflies.

    PubMed

    Xiao, Na; Pan, Li-Long; Zhang, Chang-Rong; Shan, Hong-Wei; Liu, Shu-Sheng

    2016-01-01

    Thermal response and tolerance to ambient temperature play important roles in determining the geographic distribution and seasonal abundance of insects. We examined the survival and performance, as well as expression of three heat shock protein related genes, of two species of invasive whiteflies, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), of the Bemisia tabaci species complex following exposure to a range of low and high temperatures. Our data demonstrated that the MED species was more tolerant to high temperatures than the MEAM1 species, especially in the adult stage, and this difference in thermal responses may be related to the heat shock protein related genes hsp90 and hsp70. These findings may assist in understanding and predicting the distribution and abundance of the two invasive whiteflies in the field. PMID:27080927

  18. Differential tolerance capacity to unfavourable low and high temperatures between two invasive whiteflies

    PubMed Central

    Xiao, Na; Pan, Li-Long; Zhang, Chang-Rong; Shan, Hong-Wei; Liu, Shu-Sheng

    2016-01-01

    Thermal response and tolerance to ambient temperature play important roles in determining the geographic distribution and seasonal abundance of insects. We examined the survival and performance, as well as expression of three heat shock protein related genes, of two species of invasive whiteflies, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), of the Bemisia tabaci species complex following exposure to a range of low and high temperatures. Our data demonstrated that the MED species was more tolerant to high temperatures than the MEAM1 species, especially in the adult stage, and this difference in thermal responses may be related to the heat shock protein related genes hsp90 and hsp70. These findings may assist in understanding and predicting the distribution and abundance of the two invasive whiteflies in the field. PMID:27080927

  19. Adhesive and invasive capacities of Edwarsiella tarda isolated from South American sea lion

    PubMed Central

    Fernández, Araceli; Villanueva, María Paz; González, Mario; Fernández, Fabiola; Latif, Fadua; Flores, Sandra Nonier; Fernández, Heriberto

    2014-01-01

    Edwarsiella tarda is a zoonotic bacterium that can be isolated from humans, animals and the environment. Although E. tarda is primarily considered a fish pathogen, it is the only species of its genus considered to be pathogenic for humans as well. A survey of zoonotic intestinal bacteria in fresh feces from South American sea lions (SASL) Otaria flavescens, reported E. tarda as the most frequently isolated species. In this study, we used HEp-2 cells to establish in vitro the adherence and invasive ability of 17 E. tarda strains isolated from SASL fecal material. All the strains were able to adhere and invade HEp-2 cells with adhesion and invasion percentages ranging from 56 to 100% and 21 to 74%, respectively. Despite the expression of these pathogenic factors, further investigation is needed to determine whether this bacterium could play a role as primary pathogen for this and other species of pinnipeds. PMID:25477948

  20. Keystone predators (eastern newts, Notophthalmus viridescens) reduce the impacts of an aquatic invasive species

    USGS Publications Warehouse

    Smith, Kimberly G.

    2006-01-01

    Predation, competition, and their interaction are known to be important factors that influence the structure of ecological communities. In particular, in those cases where a competitive hierarchy exists among prey species, the presence of certain keystone predators can result in enhanced diversity in the prey community. However, little is known regarding the influence of keystone predator presence on invaded prey communities. Given the widespread occurrence of invasive species and substantial concern regarding their ecological impacts, studies on this topic are needed. In this study I used naturalistic replications of an experimental tadpole assemblage to assess the influence of predatory eastern newts, Notophthalmus viridescens, on the outcome of interspecific competition among native and nonindigenous tadpoles. When newts were absent, the presence of the tadpoles of one invasive species, the Cuban treefrog, Osteopilus septentrionalis, resulted in decreased survival and growth rate of the dominant native species, Bufo terrestris, and dominance of the tadpole assemblage by O. septentrionalis. However, the presence of one adult newt generally reduced or eliminated the negative impacts of O. septentrionalis tadpoles, resulting in comparable survival and performance of native species in invaded and noninvaded treatments. Differential mortality among the tadpole species suggests that newts preyed selectively on O. septentrionalis tadpoles, supporting the hypothesis that newts acted as keystone predators in the invaded assemblage. The presence of nonindigenous larval cane toads, Bufo marinus, did not significantly affect native species, and this species was not negatively affected by the presence of newts. Collectively, these results suggest that eastern newts significantly modified the competitive hierarchy of the invaded tadpole assemblage and reduced the impacts of a competitively superior invasive species. If general, these results suggest that the presence of

  1. Reducing hypoxia and inflammation during invasive pulmonary aspergillosis by targeting the Interleukin-1 receptor.

    PubMed

    Gresnigt, Mark S; Rekiki, Abdessalem; Rasid, Orhan; Savers, Amélie; Jouvion, Grégory; Dannaoui, Eric; Parlato, Marianna; Fitting, Catherine; Brock, Matthias; Cavaillon, Jean-Marc; van de Veerdonk, Frank L; Ibrahim-Granet, Oumaïma

    2016-01-01

    Hypoxia as a result of pulmonary tissue damage due to unresolved inflammation during invasive pulmonary aspergillosis (IPA) is associated with a poor outcome. Aspergillus fumigatus can exploit the hypoxic microenvironment in the lung, but the inflammatory response required for fungal clearance can become severely disregulated as a result of hypoxia. Since severe inflammation can be detrimental to the host, we investigated whether targeting the interleukin IL-1 pathway could reduce inflammation and tissue hypoxia, improving the outcome of IPA. The interplay between hypoxia and inflammation was investigated by in vivo imaging of hypoxia and measurement of cytokines in the lungs in a model of corticosteroid immunocompromised and in Cxcr2 deficient mice. Severe hypoxia was observed following Aspergillus infection in both models and correlated with development of pulmonary inflammation and expression of hypoxia specific transcripts. Treatment with IL-1 receptor antagonist reduced hypoxia and slightly, but significantly reduced mortality in immunosuppressed mice, but was unable to reduce hypoxia in Cxcr2(-/-) mice. Our data provides evidence that the inflammatory response during invasive pulmonary aspergillosis, and in particular the IL-1 axis, drives the development of hypoxia. Targeting the inflammatory IL-1 response could be used as a potential immunomodulatory therapy to improve the outcome of aspergillosis. PMID:27215684

  2. Reducing hypoxia and inflammation during invasive pulmonary aspergillosis by targeting the Interleukin-1 receptor

    PubMed Central

    Gresnigt, Mark S.; Rekiki, Abdessalem; Rasid, Orhan; Savers, Amélie; Jouvion, Grégory; Dannaoui, Eric; Parlato, Marianna; Fitting, Catherine; Brock, Matthias; Cavaillon, Jean-Marc; van de Veerdonk, Frank L.; Ibrahim-Granet, Oumaïma

    2016-01-01

    Hypoxia as a result of pulmonary tissue damage due to unresolved inflammation during invasive pulmonary aspergillosis (IPA) is associated with a poor outcome. Aspergillus fumigatus can exploit the hypoxic microenvironment in the lung, but the inflammatory response required for fungal clearance can become severely disregulated as a result of hypoxia. Since severe inflammation can be detrimental to the host, we investigated whether targeting the interleukin IL-1 pathway could reduce inflammation and tissue hypoxia, improving the outcome of IPA. The interplay between hypoxia and inflammation was investigated by in vivo imaging of hypoxia and measurement of cytokines in the lungs in a model of corticosteroid immunocompromised and in Cxcr2 deficient mice. Severe hypoxia was observed following Aspergillus infection in both models and correlated with development of pulmonary inflammation and expression of hypoxia specific transcripts. Treatment with IL-1 receptor antagonist reduced hypoxia and slightly, but significantly reduced mortality in immunosuppressed mice, but was unable to reduce hypoxia in Cxcr2−/− mice. Our data provides evidence that the inflammatory response during invasive pulmonary aspergillosis, and in particular the IL-1 axis, drives the development of hypoxia. Targeting the inflammatory IL-1 response could be used as a potential immunomodulatory therapy to improve the outcome of aspergillosis. PMID:27215684

  3. Altering FAK-Paxillin Interactions Reduces Adhesion, Migration and Invasion Processes

    PubMed Central

    Deramaudt, Thérèse B.; Dujardin, Denis; Noulet, Fanny; Martin, Sophie; Vauchelles, Romain; Takeda, Ken; Rondé, Philippe

    2014-01-01

    Focal adhesion kinase (FAK) plays an important role in signal transduction pathways initiated at sites of integrin-mediated cell adhesion to the extracellular matrix. Thus, FAK is involved in many aspects of the metastatic process including adhesion, migration and invasion. Recently, several small molecule inhibitors which target FAK catalytic activity have been developed by pharmaceutical companies. The current study was aimed at addressing whether inhibiting FAK targeting to focal adhesions (FA) represents an efficient alternative strategy to inhibit FAK downstream pathways. Using a mutagenesis approach to alter the targeting domain of FAK, we constructed a FAK mutant that fails to bind paxillin. Inhibiting FAK-paxillin interactions led to a complete loss of FAK localization at FAs together with reduced phosphorylation of FAK and FAK targets such as paxillin and p130Cas. This in turn resulted in altered FA dynamics and inhibition of cell adhesion, migration and invasion. Moreover, the migration properties of cells expressing the FAK mutant were reduced as compared to FAK-/- cells. This was correlated with a decrease in both phospho-Src and phospho-p130Cas levels at FAs. We conclude that targeting FAK-paxillin interactions is an efficient strategy to reduce FAK signalling and thus may represent a target for the development of new FAK inhibitors. PMID:24642576

  4. Tauroursodeoxycholic acid reduces the invasion of MDA-MB-231 cells by modulating matrix metalloproteinases 7 and 13

    PubMed Central

    Park, Ga-Young; Han, Yu Kyeong; Han, Jeong Yoon; Lee, Chang Geun

    2016-01-01

    Tauroursodeoxycholic acid (TUDCA) is a conjugated form of UDCA that modulates several signaling pathways and acts as a chemical chaperone to relieve endoplasmic reticulum (ER) stress. The present study showed that TUDCA reduced the invasion of the MDA-MB-231 metastatic breast cancer cell line under normoxic and hypoxic conditions using an in vitro invasion assay. Quantitative polymerase chain reaction assay revealed that the reduced invasion following TUDCA treatment was associated with a decreased expression of matrix metalloproteinase (MMP)-7 and −13, which play important roles in invasion and metastasis. Inhibitors and short hairpin RNAs were used to show that the effect of TUDCA in the reduction of invasion appeared to be dependent on the protein kinase RNA-like ER kinase pathway, a downstream ER stress signaling pathway. Thus, TUDCA is a candidate anti-metastatic agent to target the ER stress pathway. PMID:27602168

  5. Rocky Mountain area petroleum product availability with reduced PADD IV refining capacity

    SciTech Connect

    Hadder, G.R.; Chin, S.M.

    1994-02-01

    Studies of Rocky Mountain area petroleum product availability with reduced refining capacity in Petroleum Administration for Defense IV (PADD IV, part of the Rocky Mountain area) have been performed with the Oak Ridge National Laboratory Refinery Yield Model, a linear program which has been updated to blend gasolines to satisfy constraints on emissions of nitrogen oxides and winter toxic air pollutants. The studies do not predict refinery closures in PADD IV. Rather, the reduced refining capacities provide an analytical framework for probing the flexibility of petroleum refining and distribution for winter demand conditions in the year 2000. Industry analysts have estimated that, for worst case scenarios, 20 to 35 percent of PADD IV refining capacity could be shut-down as a result of clean air and energy tax legislation. Given these industry projections, the study scenarios provide the following conclusions: The Rocky Mountain area petroleum system would have the capability to satisfy winter product demand with PADD IV refinery capacity shut-downs in the middle of the range of industry projections, but not in the high end of the range of projections. PADD IV crude oil production can be maintained by re-routing crude released from PADD IV refinery demands to satisfy increased crude oil demands in PADDs II (Midwest), III (Gulf Coast), and Washington. Clean Air Act product quality regulations generally do not increase the difficulty of satisfying emissions reduction constraints in the scenarios.

  6. Self-Disorders in Individuals with Autistic Traits: Contribution of Reduced Autobiographical Reasoning Capacities.

    PubMed

    Berna, Fabrice; Göritz, Anja S; Schröder, Johanna; Coutelle, Romain; Danion, Jean-Marie; Cuervo-Lombard, Christine V; Moritz, Steffen

    2016-08-01

    The present web-based study (N = 840) aimed to illuminate the cognitive mechanisms underlying self-disorders in autism. Initially, participants selected three self-defining memories. Then, we assessed their capacity to give meaning to these events (i.e., meaning making), their tendency to scrutinize autobiographical memory to better understand themselves (i.e., self-continuity function of autobiographical memory) and their clarity of self-concept. The results showed that individuals with high autistic traits (ATs) had a lower clarity of self-concept than control participants. Meaning making was also reduced in AT individuals and mediated the relation between AT and self-concept clarity. Our results suggest that the reduced clarity of self-concept in AT individuals is related to an impaired capacity to make meaning of important past life events. PMID:27101235

  7. Interaction between Varroa destructor and imidacloprid reduces flight capacity of honeybees.

    PubMed

    Blanken, Lisa J; van Langevelde, Frank; van Dooremalen, Coby

    2015-12-01

    Current high losses of honeybees seriously threaten crop pollination. Whereas parasite exposure is acknowledged as an important cause of these losses, the role of insecticides is controversial. Parasites and neonicotinoid insecticides reduce homing success of foragers (e.g. by reduced orientation), but it is unknown whether they negatively affect flight capacity. We investigated how exposing colonies to the parasitic mite Varroa destructor and the neonicotinoid insecticide imidacloprid affect flight capacity of foragers. Flight distance, time and speed of foragers were measured in flight mills to assess the relative and interactive effects of high V. destructor load and a field-realistic, chronic sub-lethal dose of imidacloprid. Foragers from colonies exposed to high levels of V. destructor flew shorter distances, with a larger effect when also exposed to imidacloprid. Bee body mass partly explained our results as bees were heavier when exposed to these stressors, possibly due to an earlier onset of foraging. Our findings contribute to understanding of interacting stressors that can explain colony losses. Reduced flight capacity decreases the food-collecting ability of honeybees and may hamper the use of precocious foraging as a coping mechanism during colony (nutritional) stress. Ineffective coping mechanisms may lead to destructive cascading effects and subsequent colony collapse. PMID:26631559

  8. The role of miR-21 in proliferation and invasion capacity of human tongue squamous cell carcinoma in vitro

    PubMed Central

    Wang, Yin; Zhu, Yu; Lv, Pin; Li, Longjiang

    2015-01-01

    Tongue squamous cell carcinoma is one of the most common cancers, which has the highest incidence in oral maxillofacial malignant tumors. MiR-21 may promote tumorigeness by down-regulating tumor suppressing genes and/or controlling the genes for cell differentiation and apoptosis, and it has been identified as the most expressive and unusual in a number of profiling experiments. The study shows there are high expressions of miR-21 in tongue squamous cell carcinoma cell lines (Tca8113 and its high metastatic lines), especially in high metastatic lines. miR-21 silencing could suppress the capacity of proliferation, migration and invasion, arrest the cell cycle and induce apoptosis of tongue squamous cell carcinoma cell lines (Tca8113 and its high metastatic lines). All the results indicate that miR-21 will probably open a new path to the gene therapy for oral squamous cell carcinoma. PMID:26191145

  9. The cupric ion reducing antioxidant capacity and polyphenolic content of some herbal teas.

    PubMed

    Apak, Reşat; Güçlü, Kubilay; Ozyürek, Mustafa; Esin Karademir, Saliha; Erçağ, Erol

    2006-01-01

    The total antioxidant capacity of the aqueous extracts of some endemic herbs-prepared as infusions by steeping these herbs in hot water--was assayed with bis(neocuproine)copper(II) chloride, also known as the cupric ion reducing antioxidant capacity (CUPRAC) reagent, which was easily accessible, rapid, stable and responsive to both hydrophilic and lipophilic antioxidants. The highest antioxidant capacities of some herbal teas available in the Turkish market were observed for scarlet pimpernel (Anagallis arvensis), sweet basil (Ocimum basilicum), green tea (Camellia sinensis) and lemon balm (Melissa officinalis), in this order (1.63, 1.18, 1.07, and 0.99 mmol trolox equivalent (TR)/g, respectively). For infusions prepared from ready-to-use tea bags, the CUPRAC values were highest for Ceylon blended ordinary tea (4.41), green tea with lemon (1.61), English breakfast ordinary tea (1.26) and green tea (0.94), all of which were manufactured types of C. sinensis. Following the strongest antioxidant herbs with capacities close to or slightly exceeding 1.0 mmol TR/g, sage, thyme, coriander, coltsfoot, blackberry and immortelle (Helichrysum) exhibited capacities around 0.5 mmol TR/g. The correlation of the Folin total phenolic content of herbal teas with their CUPRAC and ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) total antioxidant capacities gave linear curves with correlation coefficients of 0.966 and 0.936, respectively, showing that the CUPRAC assay results better correlated with total phenolic content of herbal teas. Absorbance versus concentration data at different dilutions and upon standard additions of model antioxidant compounds (trolox and quercetin) to herbal tea infusions showed that the absorbances (at 450 nm of the CUPRAC method) due to different antioxidant compounds in herbal tea infusions were additive; that is, the tested antioxidants did not chemically interact to cause apparent deviations from Beer's law. PMID:17135020

  10. Archipelago-wide island restoration in the Galápagos Islands: reducing costs of invasive mammal eradication programs and reinvasion risk.

    PubMed

    Carrion, Victor; Donlan, C Josh; Campbell, Karl J; Lavoie, Christian; Cruz, Felipe

    2011-01-01

    Invasive alien mammals are the major driver of biodiversity loss and ecosystem degradation on islands. Over the past three decades, invasive mammal eradication from islands has become one of society's most powerful tools for preventing extinction of insular endemics and restoring insular ecosystems. As practitioners tackle larger islands for restoration, three factors will heavily influence success and outcomes: the degree of local support, the ability to mitigate for non-target impacts, and the ability to eradicate non-native species more cost-effectively. Investments in removing invasive species, however, must be weighed against the risk of reintroduction. One way to reduce reintroduction risks is to eradicate the target invasive species from an entire archipelago, and thus eliminate readily available sources. We illustrate the costs and benefits of this approach with the efforts to remove invasive goats from the Galápagos Islands. Project Isabela, the world's largest island restoration effort to date, removed >140,000 goats from >500,000 ha for a cost of US$10.5 million. Leveraging the capacity built during Project Isabela, and given that goat reintroductions have been common over the past decade, we implemented an archipelago-wide goat eradication strategy. Feral goats remain on three islands in the archipelago, and removal efforts are underway. Efforts on the Galápagos Islands demonstrate that for some species, island size is no longer the limiting factor with respect to eradication. Rather, bureaucratic processes, financing, political will, and stakeholder approval appear to be the new challenges. Eradication efforts have delivered a suite of biodiversity benefits that are in the process of revealing themselves. The costs of rectifying intentional reintroductions are high in terms of financial and human resources. Reducing the archipelago-wide goat density to low levels is a technical approach to reducing reintroduction risk in the short-term, and is being

  11. Archipelago-Wide Island Restoration in the Galápagos Islands: Reducing Costs of Invasive Mammal Eradication Programs and Reinvasion Risk

    PubMed Central

    Carrion, Victor; Donlan, C. Josh; Campbell, Karl J.; Lavoie, Christian; Cruz, Felipe

    2011-01-01

    Invasive alien mammals are the major driver of biodiversity loss and ecosystem degradation on islands. Over the past three decades, invasive mammal eradication from islands has become one of society's most powerful tools for preventing extinction of insular endemics and restoring insular ecosystems. As practitioners tackle larger islands for restoration, three factors will heavily influence success and outcomes: the degree of local support, the ability to mitigate for non-target impacts, and the ability to eradicate non-native species more cost-effectively. Investments in removing invasive species, however, must be weighed against the risk of reintroduction. One way to reduce reintroduction risks is to eradicate the target invasive species from an entire archipelago, and thus eliminate readily available sources. We illustrate the costs and benefits of this approach with the efforts to remove invasive goats from the Galápagos Islands. Project Isabela, the world's largest island restoration effort to date, removed >140,000 goats from >500,000 ha for a cost of US$10.5 million. Leveraging the capacity built during Project Isabela, and given that goat reintroductions have been common over the past decade, we implemented an archipelago-wide goat eradication strategy. Feral goats remain on three islands in the archipelago, and removal efforts are underway. Efforts on the Galápagos Islands demonstrate that for some species, island size is no longer the limiting factor with respect to eradication. Rather, bureaucratic processes, financing, political will, and stakeholder approval appear to be the new challenges. Eradication efforts have delivered a suite of biodiversity benefits that are in the process of revealing themselves. The costs of rectifying intentional reintroductions are high in terms of financial and human resources. Reducing the archipelago-wide goat density to low levels is a technical approach to reducing reintroduction risk in the short-term, and is being

  12. Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Shibasaki, M.; Wilson, T. E.; Cui, J.; Levine, B. D.

    2003-01-01

    Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6 degrees head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42 degrees C for 45 min. Sweat gland function was assessed by administering 1 x 10(-6) to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

  13. Rapid microplate high-throughput methodology for assessment of Folin-Ciocalteu reducing capacity.

    PubMed

    Magalhães, Luís M; Santos, Fernando; Segundo, Marcela A; Reis, Salette; Lima, José L F C

    2010-12-15

    In the present work, a rapid and high-throughput Folin-Ciocalteu (F-C) reducing capacity assay adapted to routine/screening analysis was developed. In order to attain a fast F-C reducing kinetic reaction, the reaction conditions of the classical time-consuming F-C assay were modified and the influence of alkali and F-C reagent concentration was evaluated using gallic acid as standard. The proposed method was performed in a 96-well microplate format and it was applied to several phenolic compounds and food products (wines, beers, infusions and juices) providing F-C reducing capacity results after 3 min of reaction similar to those obtained by the time-consuming (120 min) conventional method. The additive and synergistic effect of reducing nonphenolic compounds usually found in food samples was also investigated. Ascorbic acid and ferrous sulfate provided an additive effect, while for fructose, glucose and sodium sulfite a synergistic effect was obtained. The detection limit was 0.25 mg L(-1) (as gallic acid) and the repeatability was <1.6% (n=12). PMID:21111158

  14. Influence of Low Molecular Weight Fractions of Humic Substances on Their Reducing Capacities and Distribution of Redox Functional Groups.

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Jiang, J.

    2015-12-01

    Humic substances (HS) are redox-active organic compounds and their reducing capacities depend on molecule structure and distribution of redox functional groups (RFG). During dialysis experiments, initial HS were separated into low molecular weight fractions (LMWF, molecular weight <3,500 Da or <14,000 Da) and retentate. LMWF accounts for only 2% in TOC contents of HS molecules, while their reducing capacities are up to 33 times greater than those of initial HA. However, great amount of reducing capacities of LMWF does not cause decreasing reducing capacities of retentate relative to those of initial HA. Total reducing capacities of whole dialysis device were calculated for initial HA, retentate and LMWF in native and reduced state, and result suggests that releasing of LMWF leads to production and explosion of RFG. LWMF have great fluorescence intensities for protein-like fluorophores and humic acids-like fluorophores (quinone-like functional groups), where quinonoid π-π* transition is responsible for the great reducing capacities of LMWF. The 3,500 Da molecules (0.25 nm diameter) of HS are capable of stimulating transformation of redox-active metals or potential pollutants trapped in soil micropores (< 2 nm diameter). A development of relationship between reducing capacity and Ex / Em position provides a possibility to predicate relative reducing capacities of HS in treated raw water sample.

  15. Invasive surgery reduces infarct size and preserves cardiac function in a porcine model of myocardial infarction

    PubMed Central

    van Hout, Gerardus PJ; Teuben, Michel PJ; Heeres, Marjolein; de Maat, Steven; de Jong, Renate; Maas, Coen; Kouwenberg, Lisanne HJA; Koenderman, Leo; van Solinge, Wouter W; de Jager, Saskia CA; Pasterkamp, Gerard; Hoefer, Imo E

    2015-01-01

    Reperfusion injury following myocardial infarction (MI) increases infarct size (IS) and deteriorates cardiac function. Cardioprotective strategies in large animal MI models often failed in clinical trials, suggesting translational failure. Experimentally, MI is induced artificially and the effect of the experimental procedures may influence outcome and thus clinical applicability. The aim of this study was to investigate if invasive surgery, as in the common open chest MI model affects IS and cardiac function. Twenty female landrace pigs were subjected to MI by transluminal balloon occlusion. In 10 of 20 pigs, balloon occlusion was preceded by invasive surgery (medial sternotomy). After 72 hrs, pigs were subjected to echocardiography and Evans blue/triphenyl tetrazoliumchloride double staining to determine IS and area at risk. Quantification of IS showed a significant IS reduction in the open chest group compared to the closed chest group (IS versus area at risk: 50.9 ± 5.4% versus 69.9 ± 3.4%, P = 0.007). End systolic LV volume and LV ejection fraction measured by echocardiography at follow-up differed significantly between both groups (51 ± 5 ml versus 65 ± 3 ml, P = 0.033; 47.5 ± 2.6% versus 38.8 ± 1.2%, P = 0.005). The inflammatory response in the damaged myocardium did not differ between groups. This study indicates that invasive surgery reduces IS and preserves cardiac function in a porcine MI model. Future studies need to elucidate the effect of infarct induction technique on the efficacy of pharmacological therapies in large animal cardioprotection studies. PMID:26282710

  16. Intermolt development reduces oxygen delivery capacity and jumping performance in the American locust (Schistocerca americana).

    PubMed

    Kirkton, Scott D; Hennessey, Lauren E; Duffy, Bridget; Bennett, Meghan M; Lee, Wah-Keat; Greenlee, Kendra J

    2012-02-01

    Among animals, insects have the highest mass-specific metabolic rates; yet, during intermolt development the tracheal respiratory system cannot meet the increased oxygen demand of older stage insects. Using locomotory performance indices, whole body respirometry, and X-ray imaging to visualize the respiratory system, we tested the hypothesis that due to the rigid exoskeleton, an increase in body mass during the intermolt period compresses the air-filled tracheal system, thereby, reducing oxygen delivery capacity in late stage insects. Specifically, we measured air sac ventilation frequency, size, and compressibility in both the abdomen and femur of early, middle, and late stage sixth instar Schistocerca americana grasshoppers. Our results show that late stage grasshoppers have a reduced air sac ventilation frequency in the femur and decreased convective capacities in the abdomen and femur. We also used X-ray images of the abdomen and femur to calculate the total proportion of tissue dedicated to respiratory structure during the intermolt period. We found that late stage grasshoppers had a lower proportion of their body dedicated to respiratory structures, especially air sacs, which convectively ventilate the tracheal system. These intermolt changes make oxygen delivery more challenging to the tissues, especially critical ones such as the jumping muscle. Indeed, late stage grasshoppers showed reduced jump frequencies compared to early stage grasshoppers, as well as decreased mass-specific CO(2) emission rates at 3 kPa PO(2). Our findings provide a mechanism to explain how body mass changes during the intermolt period reduce oxygen delivery capacity and alter an insect's life history. PMID:21965137

  17. Genetic recapitulation of human pre-eclampsia risk during convergent evolution of reduced placental invasiveness in eutherian mammals

    PubMed Central

    Elliot, Michael G.; Crespi, Bernard J.

    2015-01-01

    The relationship between phenotypic variation arising through individual development and phenotypic variation arising through diversification of species has long been a central question in evolutionary biology. Among humans, reduced placental invasion into endometrial tissues is associated with diseases of pregnancy, especially pre-eclampsia, and reduced placental invasiveness has also evolved, convergently, in at least 10 lineages of eutherian mammals. We tested the hypothesis that a common genetic basis underlies both reduced placental invasion arising through a developmental process in human placental disease and reduced placental invasion found as a derived trait in the diversification of Euarchontoglires (rodents, lagomorphs, tree shrews, colugos and primates). Based on whole-genome analyses across 18 taxa, we identified 1254 genes as having evolved adaptively across all three lineages exhibiting independent evolutionary transitions towards reduced placental invasion. These genes showed strong evidence of enrichment for associations with pre-eclampsia, based on genetic-association studies, gene-expression analyses and gene ontology. We further used in silico prediction to identify a subset of 199 genes that are likely targets of natural selection during transitions in placental invasiveness and which are predicted to also underlie human placental disorders. Our results indicate that abnormal ontogenies can recapitulate major phylogenetic shifts in mammalian evolution, identify new candidate genes for involvement in pre-eclampsia, imply that study of species with less-invasive placentation will provide useful insights into the regulation of placental invasion and pre-eclampsia, and recommend a novel comparative functional-evolutionary approach to the study of genetically based human disease and mammalian diversification. PMID:25602073

  18. Combined HPLC-CUPRAC (cupric ion reducing antioxidant capacity) assay of parsley, celery leaves, and nettle.

    PubMed

    Yildiz, Leyla; Başkan, Kevser Sözgen; Tütem, Esma; Apak, Reşat

    2008-10-19

    This study aims to identify the essential antioxidant compounds present in parsley (Petroselinum sativum) and celery (Apium graveolens) leaves belonging to the Umbelliferae (Apiaceae) family, and in stinging nettle (Urtica dioica) belonging to Urticaceae family, to measure the total antioxidant capacity (TAC) of these compounds with CUPRAC (cupric ion reducing antioxidant capacity) and ABTS spectrophotometric methods, and to correlate the TAC with high performance liquid chromatography (HPLC) findings. The CUPRAC spectrophotometric method of TAC assay using copper(II)-neocuproine (2,9-dimethyl-1,10-phenanthroline) as the chromogenic oxidant was developed in our laboratories. The individual antioxidant constituents of plant extracts were identified and quantified by HPLC on a C18 column using a modified mobile phase of gradient elution comprised of MeOH-0.2% o-phosphoric acid and UV detection for polyphenols at 280 nm. The TAC values of HPLC-quantified antioxidant constituents were found, and compared for the first time with those found by CUPRAC. The TAC of HPLC-quantified compounds accounted for a relatively high percentage of the observed CUPRAC capacities of plant extracts, namely 81% of nettle, 60-77% of parsley (in different hydrolyzates of extract and solid sample), and 41-57% of celery leaves (in different hydrolyzates). The CUPRAC total capacities of the 70% MeOH extracts of studied plants (in the units of mmol trolox g(-1)plant) were in the order: celery leaves>nettle>parsley. The TAC calculated with the aid of HPLC-spectrophotometry did not compensate for 100% of the CUPRAC total capacities, because all flavonoid glycosides subjected to hydrolysis were either not detectable with HPLC, or not converted to the corresponding aglycons (i.e., easily detectable and quantifiable with HPLC) during the hydrolysis step. PMID:18804638

  19. Invasive floating macrophytes reduce greenhouse gas emissions from a small tropical lake.

    PubMed

    Attermeyer, K; Flury, S; Jayakumar, R; Fiener, P; Steger, K; Arya, V; Wilken, F; van Geldern, R; Premke, K

    2016-01-01

    Floating macrophytes, including water hyacinth (Eichhornia crassipes), are dominant invasive organisms in tropical aquatic systems, and they may play an important role in modifying the gas exchange between water and the atmosphere. However, these systems are underrepresented in global datasets of greenhouse gas (GHG) emissions. This study investigated the carbon (C) turnover and GHG emissions from a small (0.6 km(2)) water-harvesting lake in South India and analysed the effect of floating macrophytes on these emissions. We measured carbon dioxide (CO2) and methane (CH4) emissions with gas chambers in the field as well as water C mineralization rates and physicochemical variables in both the open water and in water within stands of water hyacinths. The CO2 and CH4 emissions from areas covered by water hyacinths were reduced by 57% compared with that of open water. However, the C mineralization rates were not significantly different in the water between the two areas. We conclude that the increased invasion of water hyacinths and other floating macrophytes has the potential to change GHG emissions, a process that might be relevant in regional C budgets. PMID:26846590

  20. Blockade of TRPM8 activity reduces the invasion potential of oral squamous carcinoma cell lines.

    PubMed

    Okamoto, Yoshihiko; Ohkubo, Tsuyako; Ikebe, Tetsuro; Yamazaki, Jun

    2012-05-01

    Several members of the transient receptor potential (TRP)-channel family are expressed in cancer cells. One, cold/menthol-sensitive TRPM8, is reportedly an important player in carcinogenesis in human prostate cancer, although its involvement in oral squamous cell carcinoma (SCC) remains unclear. The present immunohistochemistry and RT-PCR results revealed intense TRPM8 expression in two SCC cell lines, HSC3 and HSC4, derived from the human tongue. Menthol, icilin, and a more specific TRPM8 agonist (WS-12) induced non-specific cation currents, with Ca2+ permeability being greater than that of Na+ or K+. The novel TRPM8 antagonist RQ-00203078 (RQ) profoundly reduced such agonist-induced cation currents. Intracellular Ca2+ imaging revealed that menthol induced both intracellular Ca2+ release and store-operated Ca2+ entry, with RQ inhibiting each effect. To assess the possible pathophysiological role of TRPM8 in oral SCC, we performed motility and invasion assays, and gelatin zymography. Menthol augmented the migration and invasion abilities of both HSC3 and HSC4 cells by potentiating MMP-9 activity. RQ suppressed all of these effects. These results may aid understanding of the pathophysiological implications of TRPM8 channels in the oral SCC cells, support TRP proteins as valuable targets for pharmaceutical intervention, and inform the targeting of oral SCC in which the prognosis is poor. PMID:22267123

  1. Invasive floating macrophytes reduce greenhouse gas emissions from a small tropical lake

    PubMed Central

    Attermeyer, K.; Flury, S.; Jayakumar, R.; Fiener, P.; Steger, K.; Arya, V.; Wilken, F.; van Geldern, R.; Premke, K.

    2016-01-01

    Floating macrophytes, including water hyacinth (Eichhornia crassipes), are dominant invasive organisms in tropical aquatic systems, and they may play an important role in modifying the gas exchange between water and the atmosphere. However, these systems are underrepresented in global datasets of greenhouse gas (GHG) emissions. This study investigated the carbon (C) turnover and GHG emissions from a small (0.6 km2) water-harvesting lake in South India and analysed the effect of floating macrophytes on these emissions. We measured carbon dioxide (CO2) and methane (CH4) emissions with gas chambers in the field as well as water C mineralization rates and physicochemical variables in both the open water and in water within stands of water hyacinths. The CO2 and CH4 emissions from areas covered by water hyacinths were reduced by 57% compared with that of open water. However, the C mineralization rates were not significantly different in the water between the two areas. We conclude that the increased invasion of water hyacinths and other floating macrophytes has the potential to change GHG emissions, a process that might be relevant in regional C budgets. PMID:26846590

  2. Suppression of SIPA-1 expression may reduce bladder cancer invasion and metastasis via the downregulation of E-cadherin and ZO-1

    PubMed Central

    ZHANG, PING; WANG, XINGHUAN

    2016-01-01

    The aim of the present study was to investigate the capacity of signal-induced proliferation-associated protein 1 (SIPA-1) to regulate bladder cancer cell invasion and metastasis. BIU-87 and T24 cells were transfected with the SIPA gene and SIPA short hairpin (sh)RNA, respectively. Western blot analysis was conducted to analyze the expression levels of SIPA-1, Ras-related protein 1 (Rap1), Rap1 guanosine triphosphate (Rap1GTP), E-cadherin and zona occludens-1 (ZO-1). Cell motility and invasion were evaluated in vitro using wound and Transwell assays. Transfected cells were inoculated into the pelvic region of BALB/c nude mice, and the number of resulting tumors was recorded after 6 weeks. Western blot analysis revealed that expression levels of E-cadherin and ZO-1 were reduced in the cells with enhanced levels of SIPA-1. By contrast, the levels of E-cadherin and ZO-1 were elevated in the cells in which SIPA-1 was knocked down. In comparison with untransfected cells, the cells with reduced levels of SIPA-1 exhibited reduced wound closure and fewer cells crossed the chamber in the Transwell experiment, whereas the cells with enhanced levels of SIPA-1 exhibited increased migration and invasion In vivo, an increased tumor count was obtained in the mice with elevated levels of SIPA-1. Therefore, the results of the present study indicate that SIPA-1 is able to regulate bladder cancer cell metastasis and invasion by reducing the expression of E-cadherin and ZO-1. PMID:26889242

  3. Biomarkers of oxidative stress and its association with the urinary reducing capacity in bus maintenance workers

    PubMed Central

    2011-01-01

    Background Exposure to particles (PM) induces adverse health effects (cancer, cardiovascular and pulmonary diseases). A key-role in these adverse effects seems to be played by oxidative stress, which is an excess of reactive oxygen species relative to the amount of reducing species (including antioxidants), the first line of defense against reactive oxygen species. The aim of this study was to document the oxidative stress caused by exposure to respirable particles in vivo, and to test whether exposed workers presented changes in their urinary levels for reducing species. Methods Bus depot workers (n = 32) exposed to particles and pollutants (respirable PM4, organic and elemental carbon, particulate metal content, polycyclic aromatic hydrocarbons, NOx, O3) were surveyed over two consecutive days. We collected urine samples before and after each shift, and quantified an oxidative stress biomarker (8-hydroxy-2'-deoxyguanosine), the reducing capacity and a biomarker of PAH exposure (1-hydroxypyrene). We used a linear mixed model to test for associations between the oxidative stress status of the workers and their particle exposure as well as with their urinary level of reducing species. Results Workers were exposed to low levels of respirable PM4 (range 25-71 μg/m3). However, urinary levels of 8-hydroxy-2'-deoxyguanosine increased significantly within each shift and between both days for non-smokers. The between-day increase was significantly correlated (p < 0.001) with the concentrations of organic carbon, NOx, and the particulate copper content. The within-shift increase in 8OHdG was highly correlated to an increase of the urinary reducing capacity (Spearman ρ = 0.59, p < 0.0001). Conclusions These findings confirm that exposure to components associated to respirable particulate matter causes a systemic oxidative stress, as measured with the urinary 8OHdG. The strong association observed between urinary 8OHdG with the reducing capacity is suggestive of protective

  4. Seed dispersal capacity and post-dispersal fate of the invasive Spartina alterniflora in saltmarshes of the Yangtze Estuary

    NASA Astrophysics Data System (ADS)

    Xiao, Derong; Zhang, Chao; Zhang, Liquan; Zhu, Zhenchang; Tian, Kun; Gao, Wei

    2016-02-01

    Spartina alterniflora is one of the most serious invasive species in the coastal saltmarshes of China. Seeds are generally considered to be the main method for this species to colonise new habitat, but little is known quantitatively about the seed dispersal capacity and post-dispersal fate (i.e., germination and survival time). We measured the duration of seed flotation, seed persistence and seed germination of S. alterniflora in three intertidal zones [low intertidal zone (LIT), middle intertidal zone (MIT) and high intertidal zone (HIT)] in the Yangtze Estuary on the eastern coast of China. The results showed that (1) the flotation time of S. alterniflora seeds ranged from 3 to 13 days, and the values were higher in HIT and MIT than in LIT; (2) the period of seed germination was from February to June, mainly in March and April, and seed source affected seed germination as the values for seeds from HIT and MIT were much higher than those from LIT, while burial sites had no effect on germination percentages, and (3) the seed persistence was less than a year regardless of seed source, which was characterised by a transient seed bank, with values being higher in HIT and MIT than in LIT. Our results suggested that low marsh plants were far less able to produce successful seeds, or conversely, that the mid-marsh location had plants with the greatest seed production and seed mass, and the high- and mid-marsh plants had good seed floatation ability, germination and survival. Thus, plants in the mid-and high-marsh may contribute disproportionally to an invasion.

  5. Obesity and Hypertension in Association with Diastolic Dysfunction Could Reduce Exercise Capacity

    PubMed Central

    Kim, JinShil; Kim, Myeong Gun; Kang, SeWon; Kim, Bong Roung; Baek, Min Young; Park, Yae Min

    2016-01-01

    Background and Objectives Empirical evidence is lacking on the cumulative disease burden of obesity and hypertension and its impact on cardiac function and exercise capacity. The purpose of this study was to determine whether the presence of obesity and hypertension together was associated with cardiac dysfunction and exercise capacity. Subjects and Methods Using a retrospective study design, medical records were reviewed for echocardiographic and treadmill exercise stress test data. Subjects were grouped according to four categories: normal control, obese, hypertensive, or obese and hypertensive. Results Obese, hypertensive persons showed significantly lower Ea and E/A ratio and greater E/Ea ratio, deceleration time, left ventricular (LV) mass, and LV mass index compared to their counter parts (normal control, obese and/or hypertensive) (all p<0.05), after controlling for age and sex. After controlling for age and sex, significant differences in exercise capacity indices were found, with the obese group having shorter exercise time, lower metabolic equivalents, and lower maximal oxygen uptake than the normal control, hypertensive, or both groups (all p<0.05). The hypertensive or obese and hypertensive group had greater maximal blood pressure compared with the normal control group (all p<0.001). Obese and hypertensive persons were approximately three times more likely to have diastolic dysfunction (odd ratio=2.96, p=0.001), when compared to the reference group (normotensive, non-obese, or hypertensive only persons). Conclusion Diastolic dysfunction was associated with obesity and/or hypertension. The cumulative risk of obesity and hypertension and their impact on diastolic dysfunction which could be modifiable could reduce exercise capacity. PMID:27275176

  6. Influence of low molecular weight fractions of humic substances on reducing capacities and distribution of redox functional groups

    NASA Astrophysics Data System (ADS)

    Yang, Zhen; Jiang, Jie

    2016-04-01

    Humic substances (HS) are redox-active organic compounds and their reducing capacities depend on their molecule structure and distribution of redox functional groups (RFG). During dialysis experiments, bulk humic acids (HA) were separated into low molecular weight fractions (LMWF) and retentate. LMWF account for only 2% of the total organic carbon content of HA molecules, however, their reducing capacities are up to 33 times greater than either those of the bulk HA or retentate. Furthermore, the total reducing capacity of the bulk HA accounts for less than 15% of the total reducing capacity of bulk HA, retentate and LMWF combined, suggesting that releasing of LMWF cannot reduce the number of RFG. RFG are neither in fixed amounts nor in uniformly distributed in bulk HA. LWMF have great fluorescence intensities for humic-like fluorophores (quinone-like functional groups), where quinonoid π-π* transition is responsible for the great reducing capacities of LMWF, and protein-like fluorophores. The 3,500 Da molecules (1.25 nm diameter) of HS could stimulate transformation of redox-active metals or potential pollutants trapped in soil micropores (< 2 nm diameter). A development of relationship between reducing capacity and Ex/Em position provides a possibility to predicate relative reducing capacities of HS in environmental samples.

  7. PreImplantation Factor (PIF*) endogenously prevents preeclampsia: Promotes trophoblast invasion and reduces oxidative stress.

    PubMed

    Barnea, E R; Vialard, F; Moindjie, H; Ornaghi, S; Dieudonne, M N; Paidas, M J

    2016-04-01

    Preeclampsia is a unique pregnancy disorder whose patho-physiology is initiated early in gestation, while clinical manifestations typically occur in mid-to-late pregnancy. Thus, prevention should optimally be initiated in early gestation. The intimate interaction between PIF, secreted early by viable embryos, and its host-mother provides insight into putative mechanisms of preeclampsia prevention. PIF is instrumental at the two critical events underlying preeclampsia. At first, shallow implantation leads to impaired placentation, oxidative stress, protein misfolding, and endothelial dysfunction. Later in gestation, hyper-oxygenation due to overflow of maternally derived oxygenated blood compromises the placenta. The first is likely involved in early preeclampsia occurrence due to reduced effectiveness of trophoblast/uterus interaction. The latter is observed with later-onset preeclampsia, caused by a breakdown in placental blood flow regulation. We reported that 1. PIF promotes implantation, endometrium receptivity, trophoblast invasion and increases pro-tolerance trophoblastic HLA-G expression and, 2. PIF protects against oxidative stress and protein misfolding, interacting with specific targets in embryo, 3. PIF regulates systemic immunity to reduce oxidative stress. Using PIF as an early preventative preeclampsia intervention could ameliorate or even prevent the disease, whose current main solution is early delivery. PMID:26257082

  8. Total Reducing Capacity in Aquifer Minerals and Sediments: Quantifying the Potential to Attenuate Cr(VI) in Groundwater

    SciTech Connect

    Sisman, S. Lara

    2015-07-20

    Hexavalent chromium, Cr(VI), is present in the environment as a byproduct of industrial processes. Due to its mobility and toxicity, it is crucial to attenuate or remove Cr(VI) from the environment. The objective of this investigation was to quantify potential natural attenuation, or reduction capacity, of reactive minerals and aquifer sediments. Samples of reduced-iron containing minerals such as ilmenite, as well as Puye Formation sediments representing a contaminated aquifer in New Mexico, were reacted with chromate. The change in Cr(VI) during the reaction was used to calculate reduction capacity. This study found that minerals that contain reduced iron, such as ilmenite, have high reducing capacities. The data indicated that sample history may impact reduction capacity tests due to surface passivation. Further, this investigation identified areas for future research including: a) refining the relationships between iron content, magnetic susceptibility and reduction capacity, and b) long term kinetic testing using fresh aquifer sediments.

  9. Highlights Regarding Host Predisposing Factors to Recurrent Vulvovaginal Candidiasis: Chronic Stress and Reduced Antioxidant Capacity.

    PubMed

    Akimoto-Gunther, Luciene; Bonfim-Mendonça, Patrícia de Souza; Takahachi, Gisele; Irie, Mary Mayumi T; Miyamoto, Sônia; Consolaro, Márcia Edilaine Lopes; Svidzinsk, Terezinha I Estivalet

    2016-01-01

    We studied host factors that could predispose women to develop recurrent vulvovaginal candidiasis (RVVC), including glycemia, insulin resistance, chronic stress, antioxidant capacity, overall immune status, local inflammation and vaginal microbiota. The presence of yeasts in vaginal culture was screened in 277 women, with or without signs and symptoms of VVC and RVVC. The presence of an inflammatory process and microbiota were analyzed through vaginal bacterioscopy and cervical-vaginal cytology, respectively. Fasting-blood samples were collected by standard venipuncture for biochemical analyses. Flow cytometry was employed to obtain the T helper/T cytotoxic lymphocyte ratio, and insulin resistance was assessed by the HOMA index (HI). Yeasts were isolated from 71 (26%) women: 23 (32.4%) with a positive culture but without symptoms (COL), 22 (31%) in an acute episode (VVC), and 26 (36.6%) with RVVC. C. albicans was the main yeast isolated in all clinical profiles. The control group (negative culture) comprised 206 women. Diabetes mellitus and insulin resistance were more associated with the positive-culture groups (COL, VVC and RVVC) than with negative ones. The RVVC group showed lower mean levels of cortisol than the control group and lower antioxidant capacity than all other groups. The T Helper/T cytotoxic lymphocyte ratio was similar in all groups. The RVVC group showed a similar level of vaginal inflammation to the control group, and lower than in the COL and VVC groups. Only the CVV group showed a reduction in vaginal lactobacillus microbiota. Our data suggest that both chronic stress (decreased early-morning cortisol levels) and reduced antioxidant capacity can be host predisposing factors to RVVC. PMID:27415762

  10. Fructose-rich diet leads to reduced aerobic capacity and to liver injury in rats

    PubMed Central

    2012-01-01

    The main purpose of this research was to investigate the alterations in the aerobic capacity and appearance of metabolic alterations in Wistar rats fed on fructose-rich diet. We separated twenty-eight rats into two groups according to diet: a control group (C) (balanced diet) and a fructose-rich diet group (F). The animals were fed these diets for 60 d (d 120 to 180). We performed insulin, glucose as well as a minimum lactate test, at d 120 and 180. At the end of the experiment, sixteen animals were euthanized, and the following main variables were analysed: aerobic capacity, the serum aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio, serum and liver triglyceride concentrations, serum and liver thiobarbituric acid reactive substance (TBARS) concentrations, serum and liver catalase and superoxide dismutase (SOD) activity and haematoxylin-eosin histology (HE) in hepatocytes. The remaining twelve animals were submitted to an analysis of their hepatic lipogenic rate. The animals fed a fructose-rich diet exhibited a reduction in aerobic capacity, glucose tolerance and insulin sensitivity and increased concentrations of triglycerides and TBARS in the liver. Catalase and SOD activities were reduced in the livers of the fructose-fed animals. In addition, the serum AST/ALT ratio was higher than that of the C group, which indicates hepatic damage, and the damage was confirmed by histology. In conclusion, the fructose-rich diet caused significant liver damage and a reduction in insulin sensitivity in the animals, which could lead to deleterious metabolic effects. PMID:22713601

  11. Highlights Regarding Host Predisposing Factors to Recurrent Vulvovaginal Candidiasis: Chronic Stress and Reduced Antioxidant Capacity

    PubMed Central

    Akimoto-Gunther, Luciene; Bonfim-Mendonça, Patrícia de Souza; Takahachi, Gisele; Irie, Mary Mayumi T.; Miyamoto, Sônia; Consolaro, Márcia Edilaine Lopes; Svidzinsk, Terezinha I. Estivalet

    2016-01-01

    We studied host factors that could predispose women to develop recurrent vulvovaginal candidiasis (RVVC), including glycemia, insulin resistance, chronic stress, antioxidant capacity, overall immune status, local inflammation and vaginal microbiota. The presence of yeasts in vaginal culture was screened in 277 women, with or without signs and symptoms of VVC and RVVC. The presence of an inflammatory process and microbiota were analyzed through vaginal bacterioscopy and cervical-vaginal cytology, respectively. Fasting-blood samples were collected by standard venipuncture for biochemical analyses. Flow cytometry was employed to obtain the T helper/T cytotoxic lymphocyte ratio, and insulin resistance was assessed by the HOMA index (HI). Yeasts were isolated from 71 (26%) women: 23 (32.4%) with a positive culture but without symptoms (COL), 22 (31%) in an acute episode (VVC), and 26 (36.6%) with RVVC. C. albicans was the main yeast isolated in all clinical profiles. The control group (negative culture) comprised 206 women. Diabetes mellitus and insulin resistance were more associated with the positive-culture groups (COL, VVC and RVVC) than with negative ones. The RVVC group showed lower mean levels of cortisol than the control group and lower antioxidant capacity than all other groups. The T Helper/T cytotoxic lymphocyte ratio was similar in all groups. The RVVC group showed a similar level of vaginal inflammation to the control group, and lower than in the COL and VVC groups. Only the CVV group showed a reduction in vaginal lactobacillus microbiota. Our data suggest that both chronic stress (decreased early-morning cortisol levels) and reduced antioxidant capacity can be host predisposing factors to RVVC. PMID:27415762

  12. Reproduction reduces photosynthetic capacity in females of the subdioecious Honckenya peploides

    NASA Astrophysics Data System (ADS)

    Sánchez-Vilas, Julia; Retuerto, Rubén

    2011-03-01

    As a consequence of the different reproductive functions performed by the sexes, sexually dimorphic/polymorphic plants may exhibit gender-related variations in the energy and resources allocated to reproduction, and in the physiological processes that underlie these differences. This study investigated whether the sexes of the subdioecious plant Honckenya peploides differ in ecophysiological traits related to photosynthetic capacity and whether possible differences depend on reproductive status and on the plant's position (edge or centre) in the population. We registered in three sites in NW Spain, the sex and density of shoots of two segregated clumps of plants. These clumps represent an extreme case of sex-ratio variation across space, with separated single-sex clumps of plants. In two of these sites we measured photosynthetic efficiencies, chlorophyll content, and specific leaf areas. In females, reproduction reduced photochemical efficiency, chlorophyll content and increased the specific leaf area, which is a key leaf trait related to photosynthetic capacity. In males, no differences due to reproduction were detected. The position within the clump affected the specific leaf area of the shoots, with shoots growing at the edge having the lowest values, regardless of the sex. Finally, the effects of position in photosynthetic efficiency and chlorophyll content where highly variable among clumps. We conclude that the differential effects of reproduction on sexes may entail different costs that could be crucial in the outcome of interactions between them, contributing to their spatial segregation.

  13. Reduced Efficiency and Capacity of Cognitive Control in Autism Spectrum Disorder.

    PubMed

    Mackie, Melissa-Ann; Fan, Jin

    2016-03-01

    Cognitive control constrains mental operations to prioritize information that reaches conscious awareness and is essential to flexible, adaptive behavior under conditions of uncertainty. Cognitive control can be compromised by neurodevelopmental disorders such as autism spectrum disorder (ASD), which is characterized by the presence of social and communicative deficits, and restricted interests/repetitive behaviors. Although prior investigations have attempted to elucidate the nature of cognitive control in ASD, whether there is an underlying information processing deficit associated with cognitive control remains unclear. This study challenged cognitive control in 15 high-functioning adults with ASD and 15 typically developing (TD) controls using three novel tasks designed to systematically manipulate uncertainty. We aimed to investigate the efficiency of cognitive control in sequential information processing, cognitive control of nonsequential information processing across a range of cognitive loads and cognitive control capacity under time constraint. Results demonstrated that the ASD group performed less efficiently on sequential and nonsequential information processing, and had reduced cognitive control capacity under time constraint relative to the TD group. These findings suggest that inefficient cognitive control of information processing may be a fundamental deficit in ASD. PMID:26171787

  14. HDAC inhibition radiosensitizes human normal tissue cells and reduces DNA Double-Strand Break repair capacity.

    PubMed

    Purrucker, Jan C; Fricke, Andreas; Ong, Mei Fang; Rübe, Christian; Rübe, Claudia E; Mahlknecht, Ulrich

    2010-01-01

    HDAC inhibitors (HDACi) are gaining increasing attention in the treatment of cancer, particularly in view of their therapeutic effectiveness and assumed mild toxicity profile. While numerous studies have investigated the role of HDACi in tumor cells, little is known about their effects on normal tissue cells. We studied the effect of suberoylanilide hydroxamic acid (SAHA), MS275, sodium-butyrate and valproic acid in healthy human fibroblasts and found HDACi-treatment to go along with increased radiosensitivity and reduced DSB repair capacity. In view of the potential genotoxic effects of HDACi-treatment, particularly when being administered long-term for chronic disease or when given to children, to women of childbearing age or their partners or in combination with radiotherapy, an extensive education of patients and prescribing physicians as well as a stringent definition of clinical indications is urgently required. PMID:19956891

  15. The impact of using reduced capacity baskets on cask fleet size and cask fleet mix

    SciTech Connect

    Joy, D.S.; Johnson, P.E.; Andress, D.A.

    1993-06-01

    The Civilian Radioactive Waste Management System transportation system will encounter a wide range of spent fuel characteristics. Since the Initiative I casks are being designed to transport 10-year-old fuel with a burnup of 35,000 MWd/MTU, there is a good likelihood that a number of the cask shipments will need to be derated in order to meet the Nuclear Regulatory Commission radiation guidelines. This report discusses the impact of cask derating by using reduced-capacity baskets. Cask derating, while enhancing the ability to move spent fuel with a wider range of age and burnup characteristics, increases the number of shipments; the amount of equipment (cask bodies, baskets, etc.); and the number of visits to both shipping and receiving sites required to transport a specific amount of spent fuel.

  16. Landscape corridors can increase invasion by an exotic species and reduce diversity of native species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although corridors have become commonplace in conservation to mitigate negative effects of habitat fragmentation, concerns persist that they may facilitate spread of invasive species. In a large-scale experiment, we measured effects of corridors on invasive fire ants, Solenopsis invicta, and on comm...

  17. Building capacity for national carbon measurements for reducing emissions from deforestation and forest degradation

    NASA Astrophysics Data System (ADS)

    Goetz, S. J.; Laporte, N.; Horning, N.; Pelletier, J.; Jantz, P.; Ndunda, P.

    2014-12-01

    Many tropical countries are now working on developing their strategies for reducing emissions from deforestation and forest degradation, including activities that result in conservation or enhancement of forest carbon stocks and sustainable management of forests to effectively decrease atmospheric carbon emissions (i.e. REDD+). A new international REDD+ agreement is at the heart of recent negotiations of the parties to the UN Framework Convention on Climate Change (UNFCCC). REDD+ mechanisms could provide an opportunity to not only diminish an important source of emissions, but also to promote large-scale conservation of tropical forests and establish incentives and opportunities to alleviate poverty. Most tropical countries still lack basic information for developing and implementing their forest carbon stock assessments, including the extent of forest area and the rate at which forests are being cleared and/or degraded, and the carbon amounts associated with these losses. These same countries also need support to conduct integrated assessments of the most promising approaches for reducing emissions, and in identifying those policy options that hold the greatest potential while minimizing potential negative impacts of REDD+ policies. The WHRC SERVIR project in East Africa is helping to provide these data sets to countries via best practice tools and methods to support cost effective forest carbon monitoring solutions and more informed decision making processes under REDD+. We will present the results of our capacity building activites in the region and planned future efforts being coordinated with the NASA-SERVIR Hub in Kenya to support to REDD+ decision support.

  18. Candidate Antimetastasis Drugs Suppress the Metastatic Capacity of Breast Cancer Cells by Reducing Membrane Fluidity.

    PubMed

    Zhao, Weina; Prijic, Sara; Urban, Bettina C; Tisza, Michael J; Zuo, Yan; Li, Lin; Tan, Zhi; Chen, Xiaoling; Mani, Sendurai A; Chang, Jeffrey T

    2016-04-01

    Despite the high mortality from metastatic cancer, therapeutic targets to prevent metastasis are limited. Efforts to identify genetic aberrations that predispose tumors to metastasis have been mostly unsuccessful. To understand the nature of candidate targets for metastatic disease, we performed an in silico screen to identify drugs that can inhibit a gene expression signature associated with epithelial-mesenchymal transition (EMT). Compounds discovered through this method, including those previously identified, appeared to restrict metastatic capacity through a common mechanism, the ability to modulate the fluidity of cell membranes. Treatment of breast cancer cell lines with the putative antimetastasis agents reduced membrane fluidity, resulting in decreased cell motility, stem cell-like properties, and EMT in vitro, and the drugs also inhibited spontaneous metastasis in vivo When fluidity was unchanged, the antimetastasis compounds could no longer restrict metastasis, indicating a causal association between fluidity and metastasis. We further demonstrate that fluidity can be regulated by cellular cholesterol flux, as the cholesterol efflux channel ABCA1 potentiated metastatic behaviors in vitro and in vivo The requirement for fluidity was further supported by the finding in breast cancer patients that ABCA1 was overexpressed in 41% of metastatic tumors, reducing time to metastasis by 9 years. Collectively, our findings reveal increased membrane fluidity as a necessary cellular feature of metastatic potential that can be controlled by many currently available drugs, offering a viable therapeutic opportunity to prevent cancer metastasis. Cancer Res; 76(7); 2037-49. ©2016 AACR. PMID:26825169

  19. Reduced Skeletal Muscle Oxidative Capacity and Elevated Ceramide but not Diacylglycerol Content in Severe Obesity

    PubMed Central

    Coen, P.M.; Hames, K.C.; Leachman, E.M.; DeLany, J.P.; Ritov, V.B.; Menshikova, E.V.; Dubé, J.J.; Stefanovic-Racic, M.; Toledo, F.G.S.; Goodpaster, B.H.

    2014-01-01

    Objective The link between a reduced capacity for skeletal muscle mitochondrial fatty acid oxidation (FAO) and lipotoxicity in human insulin resistance has been the subject of intense debate. The objective of this study was to investigate whether reduced FAO is associated with elevated acyl CoA, ceramide, and diacylglycerol (DAG) in severely obese insulin resistant subjects. Design and Methods Muscle biopsies were conducted in lean (L, 22.6 ± 0.5 kg/m2, n = 8), Class I (CI, 32.1 ± 0.4 kg/m2, n = 7) and Class II&III obese (CII&III, 45.6 ± 1.1 kg/m2, n = 15) women for acyl CoA, sphingolipid and DAG profiling. Intramyocellular triglyceride (IMTG) content was determined by histology. FAO was assessed by incubating muscle homogenates with [1–14C]palmitate and measuring 14CO2 production. Cardiolipin content was quantified as an index of mitochondrial content. Lipid metabolism proteins, DGAT1, PLIN5, and PNPLA2 were quantified in biopsy samples by western blot. Results CII&III were more insulin resistant (HOMA-IR: 4.5 ± 0.5 vs. 1.1 ± 0.1, P < 0.001), and had lower FAO (~58%, P = 0.007) and cardiolipin content (~31%, P = 0.013) compared to L. IMTG was elevated in CI (P = 0.04) and CII&III (P = 0.04) compared to L. Sphingolipid content was higher in CII&III compared to L (13.6 ± 1.1 vs. 10.3 ± 0.5 pmol/mg, P = 0.031) whereas DAG content was not different among groups. DGAT1 was elevated in CII&III, and PLIN5 was elevated in CI compared to L. Conclusions Severe obesity is associated with reduced muscle oxidative capacity and occurs concomitantly with elevated IMTG, ceramide and insulin resistance. PMID:23512750

  20. Reduced aerobic capacity causes leaky ryanodine receptors that trigger arrhythmia in a rat strain artificially selected and bred for low aerobic running capacity

    PubMed Central

    Høydal, MA; Stølen, TO; Johnsen, AB; Alvez, M; Catalucci, D; Condorelli, G; Koch, LG; Britton, SL; Smith, GL; Wisløff, U

    2014-01-01

    Aim Rats selectively bred for inborn Low Capacity of Running (LCR) display a series of poor health indices where as rats selected for High Capacity of Running (HCR) display a healthy profile. We hypothesized that selection of low aerobic capacity over generations leads to a phenotype with increased diastolic Ca2+ leak that trigger arrhythmia. Methods We used rats selected for HCR (N=10) or LCR (N=10) to determine the effect of inborn aerobic capacity on Ca2+ leak and susceptibility of ventricular arrhythmia. We studied isolated FURA2/AM loaded cardiomyocytes to detect Ca2+-handling and function on an inverted epi-fluorescence microscope. To determine arrhythmogenicity we did a final experiment with electrical burst pacing in Langendorff perfused hearts. Results Ca2+-handling was impaired by reduced Ca2+ amplitude, prolonged time to 50% Ca2+ decay, and reduced sarcoplasmic reticulum (SR) Ca2+-content. Impaired Ca2+ removal was influenced by reduced SR Ca2+ ATP-ase 2a (SERCA2a) function and increased sodium/Ca2+-exchanger (NCX) in LCR rats. Diastolic Ca2 leak was 87% higher in LCR rats. The leak was reduced by CaMKII inhibition. Expression levels of phosphorylated theorine-286 CaMKII levels and increased RyR2 phosphorylation at the Serine-2814 site mechanistically support our findings of increased leak in LCR. LCR rats had significantly higher incidence of ventricular fibrillation. Conclusion Selection of inborn low aerobic capacity over generations leads to a phenotype with increased risk of ventricular fibrillation. Increased phosphorylation of CaMKII at serine-2814 at the cardiac ryanodine receptor appears as an important mechanism of impaired Ca2+ handling and diastolic Ca2+ leak that results in increased susceptibility to ventricular fibrillation. PMID:24444142

  1. Reduced capacity for fatty acid oxidation in rats with inherited susceptibility to diet-induced obesity.

    PubMed

    Ji, Hong; Friedman, Mark I

    2007-08-01

    High-fat, energy-dense diets promote weight gain and obesity in humans and other animals, but the mechanisms underlying such diet-induced obesity remain elusive. To determine whether a reduced capacity to oxidize fat is involved in the etiology of diet-induced obesity, we examined different measures of fatty acid oxidation in rats selectively bred for susceptibility (DIO) or resistance (DR) to dietary obesity before and after they were fed a high-fat diet and became obese. DIO rats eating a low-fat diet oxidized less dietary fatty acid in vivo and had lower levels of plasma ketone bodies during fasting compared with DR rats. Lean DIO rats fed a low-fat diet showed reduced liver messenger RNA expression of CD36, which transports fatty acids across cell membranes, and long-chain acyl-coenzyme A dehydrogenase (ACADL), which catalyzes the first step in the mitochondrial beta-oxidation of fatty acids. The deficit in CD36 and ACADL messenger RNA expression was also seen in obese DIO rats that had been eating a high-fat diet and, in addition, was accompanied by reduced expression of liver carnitine palmitoyl transferase I, the enzyme that mediates transport of long-chain fatty acids into mitochondria. No differences were found in the expression of liver enzymes involved in fat synthesis; however, in muscle, DIO rats fed the low-fat, but not high-fat, diet showed greater expression of diacylglycerol O-acyltransferase 1 and lipoprotein lipase than did DR rats. Expression of muscle enzymes involved in fatty acid oxidation was similar in the 2 groups. These findings provide a metabolic mechanism for the development of diet-induced obesity and thus suggest potential targets for intervention strategies to treat or prevent it. PMID:17618960

  2. Inhibition of STAT3 reduces proliferation and invasion in salivary gland adenoid cystic carcinoma

    PubMed Central

    Bu, Lin-Lin; Deng, Wei-Wei; Huang, Cong-Fa; Liu, Bing; Zhang, Wen-Feng; Sun, Zhi-Jun

    2015-01-01

    In this study, we accessed the expression and correlation of p-STAT3 with Survivin, Cyclin D1, CD147, Slug and Ki67 by immunohistochemical staining of human tissue microarray which contains 72 adenoid cystic carcinoma (AdCC), 12 pleomorphic adenoma (PMA) and 18 normal salivary gland (NSG) using digital pathological scanner and scoring system. We found that the expression of p-STAT3, Survivin, Slug, Cyclin D1 and CD147 was significantly increased in AdCC as compared with PMA and (or) NSG (p<0.05). While, the level of p-STAT3 and expression of Cyclin D1 and CD147 was not associated with pathological type of human AdCC (p>0.05). Correlation analysis of these proteins revealed that p-STAT3 up-regulates the expression of Survivin, Slug, Cyclin D1 and CD147 (p<0.05). Moreover, the activation of STAT3 was associated with proliferation marker Ki-67 (p<0.05). Selective inhibition of STAT3 by a small molecule S3I-201 significantly reduced human SACC-83 and SACC-LM cells proliferation, migration and invasion with the corresponding decrease in expression of Survivin, Slug, Cyclin D1 and CD147. These findings indicate that high phosphorylation level of STAT3 in AdCC is related to Survivin, Slug, Cyclin D1 and CD147. We suggest that the inhibition of STAT3 may be a novel strategy for neoadjuvant chemotherapeutic treatment of AdCC. PMID:26175943

  3. Inhibition of STAT3 reduces proliferation and invasion in salivary gland adenoid cystic carcinoma.

    PubMed

    Bu, Lin-Lin; Deng, Wei-Wei; Huang, Cong-Fa; Liu, Bing; Zhang, Wen-Feng; Sun, Zhi-Jun

    2015-01-01

    In this study, we accessed the expression and correlation of p-STAT3 with Survivin, Cyclin D1, CD147, Slug and Ki67 by immunohistochemical staining of human tissue microarray which contains 72 adenoid cystic carcinoma (AdCC), 12 pleomorphic adenoma (PMA) and 18 normal salivary gland (NSG) using digital pathological scanner and scoring system. We found that the expression of p-STAT3, Survivin, Slug, Cyclin D1 and CD147 was significantly increased in AdCC as compared with PMA and (or) NSG (p<0.05). While, the level of p-STAT3 and expression of Cyclin D1 and CD147 was not associated with pathological type of human AdCC (p>0.05). Correlation analysis of these proteins revealed that p-STAT3 up-regulates the expression of Survivin, Slug, Cyclin D1 and CD147 (p<0.05). Moreover, the activation of STAT3 was associated with proliferation marker Ki-67 (p<0.05). Selective inhibition of STAT3 by a small molecule S3I-201 significantly reduced human SACC-83 and SACC-LM cells proliferation, migration and invasion with the corresponding decrease in expression of Survivin, Slug, Cyclin D1 and CD147. These findings indicate that high phosphorylation level of STAT3 in AdCC is related to Survivin, Slug, Cyclin D1 and CD147. We suggest that the inhibition of STAT3 may be a novel strategy for neoadjuvant chemotherapeutic treatment of AdCC. PMID:26175943

  4. Parasites reduce food web robustness because they are sensitive to secondary extinction as illustrated by an invasive estuarine snail.

    PubMed

    Lafferty, Kevin D; Kuris, Armand M

    2009-06-27

    A robust food web is one in which few secondary extinctions occur after removing species. We investigated how parasites affected the robustness of the Carpinteria Salt Marsh food web by conducting random species removals and a hypothetical, but plausible, species invasion. Parasites were much more likely than free-living species to suffer secondary extinctions following the removal of a free-living species from the food web. For this reason, the food web was less robust with the inclusion of parasites. Removal of the horn snail, Cerithidea californica, resulted in a disproportionate number of secondary parasite extinctions. The exotic Japanese mud snail, Batillaria attramentaria, is the ecological analogue of the native California horn snail and can completely replace it following invasion. Owing to the similarities between the two snail species, the invasion had no effect on predator-prey interactions. However, because the native snail is host for 17 host-specific parasites, and the invader is host to only one, comparison of a food web that includes parasites showed significant effects of invasion on the native community. The hypothetical invasion also significantly reduced the connectance of the web because the loss of 17 native trematode species eliminated many links. PMID:19451117

  5. Synergy of extreme drought and shrub invasion reduce ecosystem functioning and resilience in water-limited climates

    NASA Astrophysics Data System (ADS)

    Caldeira, Maria C.; Lecomte, Xavier; David, Teresa S.; Pinto, Joaquim G.; Bugalho, Miguel N.; Werner, Christiane

    2015-10-01

    Extreme drought events and plant invasions are major drivers of global change that can critically affect ecosystem functioning and alter ecosystem-atmosphere exchange. Invaders are expanding worldwide and extreme drought events are projected to increase in frequency and intensity. However, very little is known on how these drivers may interact to affect the functioning and resilience of ecosystems to extreme events. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that native shrub invasion and extreme drought synergistically reduced ecosystem transpiration and the resilience of key-stone oak tree species. Ecosystem transpiration was dominated by the water use of the invasive shrub Cistus ladanifer, which further increased after the extreme drought event. Meanwhile, the transpiration of key-stone tree species decreased, indicating a competitive advantage in favour of the invader. Our results suggest that in Mediterranean-type climates the invasion of water spending species and projected recurrent extreme drought events may synergistically cause critical drought tolerance thresholds of key-stone tree species to be surpassed, corroborating observed higher tree mortality in the invaded ecosystems. Ultimately, this may shift seasonally water limited ecosystems into less desirable alternative states dominated by water spending invasive shrubs.

  6. Synergy of extreme drought and shrub invasion reduce ecosystem functioning and resilience in water-limited climates

    PubMed Central

    Caldeira, Maria C.; Lecomte, Xavier; David, Teresa S.; Pinto, Joaquim G.; Bugalho, Miguel N.; Werner, Christiane

    2015-01-01

    Extreme drought events and plant invasions are major drivers of global change that can critically affect ecosystem functioning and alter ecosystem-atmosphere exchange. Invaders are expanding worldwide and extreme drought events are projected to increase in frequency and intensity. However, very little is known on how these drivers may interact to affect the functioning and resilience of ecosystems to extreme events. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that native shrub invasion and extreme drought synergistically reduced ecosystem transpiration and the resilience of key-stone oak tree species. Ecosystem transpiration was dominated by the water use of the invasive shrub Cistus ladanifer, which further increased after the extreme drought event. Meanwhile, the transpiration of key-stone tree species decreased, indicating a competitive advantage in favour of the invader. Our results suggest that in Mediterranean-type climates the invasion of water spending species and projected recurrent extreme drought events may synergistically cause critical drought tolerance thresholds of key-stone tree species to be surpassed, corroborating observed higher tree mortality in the invaded ecosystems. Ultimately, this may shift seasonally water limited ecosystems into less desirable alternative states dominated by water spending invasive shrubs. PMID:26461978

  7. Synergy of extreme drought and shrub invasion reduce ecosystem functioning and resilience in water-limited climates.

    PubMed

    Caldeira, Maria C; Lecomte, Xavier; David, Teresa S; Pinto, Joaquim G; Bugalho, Miguel N; Werner, Christiane

    2015-01-01

    Extreme drought events and plant invasions are major drivers of global change that can critically affect ecosystem functioning and alter ecosystem-atmosphere exchange. Invaders are expanding worldwide and extreme drought events are projected to increase in frequency and intensity. However, very little is known on how these drivers may interact to affect the functioning and resilience of ecosystems to extreme events. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that native shrub invasion and extreme drought synergistically reduced ecosystem transpiration and the resilience of key-stone oak tree species. Ecosystem transpiration was dominated by the water use of the invasive shrub Cistus ladanifer, which further increased after the extreme drought event. Meanwhile, the transpiration of key-stone tree species decreased, indicating a competitive advantage in favour of the invader. Our results suggest that in Mediterranean-type climates the invasion of water spending species and projected recurrent extreme drought events may synergistically cause critical drought tolerance thresholds of key-stone tree species to be surpassed, corroborating observed higher tree mortality in the invaded ecosystems. Ultimately, this may shift seasonally water limited ecosystems into less desirable alternative states dominated by water spending invasive shrubs. PMID:26461978

  8. Abnormal transsulfuration metabolism and reduced antioxidant capacity in Chinese children with autism spectrum disorders.

    PubMed

    Han, Yu; Xi, Qian-qian; Dai, Wei; Yang, Shu-han; Gao, Lei; Su, Yuan-yuan; Zhang, Xin

    2015-11-01

    Autism spectrum disorder (ASD) is a neurological disorder that presents a spectrum of qualitative impairments in social interaction, communication, as well as restricted and stereotyped behavioral patterns, interests, and activities. Several studies have suggested that the etiology of ASD can be partly explained by oxidative stress. However, the implications of abnormal transsulfuration metabolism and oxidative stress, and their relation with ASD are still unclear. The purpose of this study was to evaluate several transsulfuration pathway metabolites in Chinese participants diagnosed with ASD, to better understand their role in the etiology of this disorder. Fifty children (39 male, 11 female) diagnosed with ASD and 50 age- and gender-matched non-ASD children (i.e., control group) were included in this study. This prospective blinded study was undertaken to assess transsulfuration and oxidative metabolites, including levels of homocysteine (Hcy), cysteine (Cys), total glutathione (tGSH), reduced glutathione (GSH), oxidized glutathione (GSSG), and glutathione ratio (GSH/GSSG). The clinical severity of ASD was evaluated with the Childhood Autism Rating Scale (CARS), and the autistic children's present behavior was measured by the Autism Behavior Checklist (ABC). The results indicated that Hcy and GSSG levels were significantly higher in children diagnosed with ASD, Cys, tGSH and GSH levels as well as the GSH/GSSG ratio showed remarkably lower values in ASD children compared to control subjects. Hcy levels correlated significantly with increasing CARS scores and GSSG levels in children with ASD. Our results suggest that an abnormal transsulfuration metabolism and reduced antioxidant capacity (i.e., hyperhomocysteinemia and increased oxidative stress), and Hcy level appears to have a potentially negative impact on clinical severity of autistic disorder. PMID:26150135

  9. Elastin-derived peptides increase invasive capacities of lung cancer cells by post-transcriptional regulation of MMP-2 and uPA.

    PubMed

    Toupance, Simon; Brassart, Bertrand; Rabenoelina, Fanja; Ghoneim, Christelle; Vallar, Laurent; Polette, Myriam; Debelle, Laurent; Birembaut, Philippe

    2012-06-01

    Elastin-rich lung extracellular matrix is largely remodeled during tumor invasion. Elastin degradation produces peptides displaying a wide range of biological activities. These elastin derived peptides (EP) interact with the elastin receptor complex (ERC) but also bind to α(V)β(3) integrin and galectin-3. In this study, we explored the role of EP and their receptors in tumor progression of lung carcinomas. Non-invasive and invasive lung tumor cell lines were incubated in presence of kappa-elastin (κE) or with synthetic peptides displaying receptor-specific sequences (VGVAPG, GRKRK, AGVPGLGVG and AGVPGFGAG). Modified Boyden chamber assays revealed an increased invasive capacity of invasive cells induced by κE. EP treatment had no effect on cell proliferation but zymography analysis revealed an increase of pro-MMP-2 and uPA levels in the conditioned media of treated cells. Moreover, the active form of MMP-2 was increased in invasive cells. Interestingly, this regulation was not observed at the mRNA level and actinomycin D was unable to inhibit κE effects. We also observed that the regulation of proteases protein level following κE treatment was an early process detectable after 1 h. All these effects could not be inhibited by lactose and V14, two ERC antagonists, or by blocking antibodies against α(V)β(3) integrin and galectin-3. Finally, VGVAPG and GRKRK failed to reproduce κE effects whereas nonapeptides partially mimicked them. These results demonstrate that treatment with EP up-regulates invasiveness of lung tumor cells via the release of proteolytic enzymes. This modulation involves post-transcriptional mechanisms and a nonapeptide-receptor different from the ERC, α(V)β(3) integrin and galectin-3. PMID:22434583

  10. Suppression of cerebral hemodynamics is associated with reduced functional capacity in patients with heart failure

    PubMed Central

    Fu, Tieh-Cheng; Wang, Chao-Hung; Hsu, Chih-Chin; Cherng, Wen-Jin; Huang, Shu-Chun

    2011-01-01

    ventilatory abnormality, which reduces functional capacity in patients with HF. PMID:21278137

  11. Effects of Spartina alterniflora invasion on the communities of methanogens and sulfate-reducing bacteria in estuarine marsh sediments

    PubMed Central

    Zeleke, Jemaneh; Sheng, Qiang; Wang, Jian-Gong; Huang, Ming-Yao; Xia, Fei; Wu, Ji-Hua; Quan, Zhe-Xue

    2013-01-01

    The effect of plant invasion on the microorganisms of soil sediments is very important for estuary ecology. The community structures of methanogens and sulfate-reducing bacteria (SRB) as a function of Spartina alterniflora invasion in Phragmites australis-vegetated sediments of the Dongtan wetland in the Yangtze River estuary, China, were investigated using 454 pyrosequencing and quantitative real-time PCR (qPCR) of the methyl coenzyme M reductase A (mcrA) and dissimilatory sulfite-reductase (dsrB) genes. Sediment samples were collected from two replicate locations, and each location included three sampling stands each covered by monocultures of P. australis, S. alterniflora and both plants (transition stands), respectively. qPCR analysis revealed higher copy numbers of mcrA genes in sediments from S. alterniflora stands than P. australis stands (5- and 7.5-fold more in the spring and summer, respectively), which is consistent with the higher methane flux rates measured in the S. alterniflora stands (up to 8.01 ± 5.61 mg m−2 h−1). Similar trends were observed for SRB, and they were up to two orders of magnitude higher than the methanogens. Diversity indices indicated a lower diversity of methanogens in the S. alterniflora stands than the P. australis stands. In contrast, insignificant variations were observed in the diversity of SRB with the invasion. Although Methanomicrobiales and Methanococcales, the hydrogenotrophic methanogens, dominated in the salt marsh, Methanomicrobiales displayed a slight increase with the invasion and growth of S. alterniflora, whereas the later responded differently. Methanosarcina, the metabolically diverse methanogens, did not vary with the invasion of, but Methanosaeta, the exclusive acetate utilizers, appeared to increase with S. alterniflora invasion. In SRB, sequences closely related to the families Desulfobacteraceae and Desulfobulbaceae dominated in the salt marsh, although they displayed minimal changes with the S

  12. Reducing the risk of invasive forest pests and pathogens: Combining legislation, targeted management and public awareness.

    PubMed

    Klapwijk, Maartje J; Hopkins, Anna J M; Eriksson, Louise; Pettersson, Maria; Schroeder, Martin; Lindelöw, Åke; Rönnberg, Jonas; Keskitalo, E Carina H; Kenis, Marc

    2016-02-01

    Intensifying global trade will result in increased numbers of plant pest and pathogen species inadvertently being transported along with cargo. This paper examines current mechanisms for prevention and management of potential introductions of forest insect pests and pathogens in the European Union (EU). Current European legislation has not been found sufficient in preventing invasion, establishment and spread of pest and pathogen species within the EU. Costs associated with future invasions are difficult to estimate but past invasions have led to negative economic impacts in the invaded country. The challenge is combining free trade and free movement of products (within the EU) with protection against invasive pests and pathogens. Public awareness may mobilise the public for prevention and detection of potential invasions and, simultaneously, increase support for eradication and control measures. We recommend focus on commodities in addition to pathways, an approach within the EU using a centralised response unit and, critically, to engage the general public in the battle against establishment and spread of these harmful pests and pathogens. PMID:26744056

  13. Landscape corridors can increase invasion by an exotic species and reduce diversity of native species.

    SciTech Connect

    Resasco, Julian; et al,

    2014-04-01

    Abstract. Landscape corridors are commonly used to mitigate negative effects of habitat fragmentation, but concerns persist that they may facilitate the spread of invasive species. In a replicated landscape experiment of open habitat, we measured effects of corridors on the invasive fire ant, Solenopsis invicta, and native ants. Fire ants have two social forms: polygyne, which tend to disperse poorly but establish at high densities, and monogyne, which disperse widely but establish at lower densities. In landscapes dominated by polygyne fire ants, fire ant abundance was higher and native ant diversity was lower in habitat patches connected by corridors than in unconnected patches. Conversely, in landscapes dominated by monogyne fire ants, connectivity had no influence on fire ant abundance and native ant diversity. Polygyne fire ants dominated recently created landscapes, suggesting that these corridor effects may be transient. Our results suggest that corridors can facilitate invasion and they highlight the importance of considering species’ traits when assessing corridor utility.

  14. The role of YY1 in reduced HP1α gene expression in invasive human breast cancer cells

    PubMed Central

    Lieberthal, Jason G; Kaminsky, Marissa; Parkhurst, Christopher N; Tanese, Naoko

    2009-01-01

    Introduction Heterochromatin protein 1 (HP1) associates with chromatin by binding to histone H3 and contributes to gene silencing. There are three isoforms of HP1 in mammals: HP1α, β, and γ. Studies have shown that the level of HP1α is reduced in invasive human breast cancer cell lines such as MDA-MB-231 and HS578T compared with non-invasive cell lines such as MCF7 and T47D. It is hypothesized that reduced HP1α expression may lead to impaired epigenetic silencing of genes that are important in the acquisition of an invasive phenotype. We set out to determine whether reduced expression of HP1α in invasive breast cancer cell lines occurs at the level of transcription. Methods We used transient transfection assays to investigate the mechanism of differential transcriptional activity of the human HP1α gene promoter in different cell lines. Mutational analysis of putative transcription factor binding sites in an HP1α gene reporter construct was performed to identify transcription factors responsible for the differential activity. SiRNA-mediated knockdown and chromatin immunoprecipitation experiments were performed to determine the role of a specific transcription factor in regulating the HP1α gene. Results The transcription factor yin yang 1 (YY1) was found to play a role in differential transcriptional activity of the HP1α gene. Examination of the YY1 protein and mRNA levels revealed that both were reduced in the invasive cell line HS578T compared with MCF7 cells. YY1 knockdown in MCF7 cells resulted in a decreased level of HP1α mRNA, indicating that YY1 positively regulates HP1α expression. Chromatin immunoprecipitation experiments verified YY1 occupancy at the HP1α gene promoter in MCF7 cells but not HS578T cells. Overexpression of YY1 in HS578T cells decreased cell migration in a manner independent of HP1α overexpression. Conclusions Our data suggests that a reduction of YY1 expression in breast cancer cells could contribute to the acquisition of an

  15. Loss of the histone chaperone ASF1B reduces female reproductive capacity in mice.

    PubMed

    Messiaen, S; Guiard, J; Aigueperse, C; Fliniaux, I; Tourpin, S; Barroca, V; Allemand, I; Fouchet, P; Livera, G; Vernet, M

    2016-05-01

    Anti-silencing function 1 (ASF1) is an evolutionarily conserved histone H3-H4 chaperone involved in the assembly/disassembly of nucleosome and histone modification. Two paralogous genes, Asf1a and Asf1b, exist in the mouse genome. Asf1a is ubiquitously expressed and its loss causes embryonic lethality. Conversely, Asf1b expression is more restricted and has been less studied. To determine the in vivo function of Asf1b, we generated a Asf1b-deficient mouse line (Asf1b(GT(ROSA-βgeo)437)) in which expression of the lacZ reporter gene is driven by the Asf1b promoter. Analysis of β-galactosidase activity at early embryonic stages indicated a correlation between Asf1b expression and cell differentiation potential. In the gonads of both male and female, Asf1b expression was specifically detected in the germ cell lineage with a peak expression correlated with meiosis. The viability of Asf1b-null mice suggests that Asf1b is dispensable for mouse development. However, these mice showed reduced reproductive capacity compared with wild-type controls. We present evidence that the timing of meiotic entry and the subsequent gonad development are affected more severely in Asf1b-null female mice than in male mice. In female mice, in addition to subfertility related to altered gamete formation, variable defects compromising the development and/or survival of their offspring were also observed. Altogether, our data indicate the importance of Asf1b expression at the time of meiotic entry, suggesting that chromatin modifications may play a central role in this process. PMID:26850882

  16. Invasive Mycosis Due to Species of Blastobotrys in Immunocompromised Patients with Reduced Susceptibility to Antifungals

    PubMed Central

    Kumar, Anil; Babu, Rachana; Bijulal, Swapna; Abraham, Mohan; Sasidharan, P.; Kathuria, Shallu; Sharma, Cheshta; Meis, Jacques F.

    2014-01-01

    Cases of invasive mycosis due to Blastobotrys serpentis and B. proliferans identified by sequencing in a preterm patient and a rhabdomyosarcoma patient, respectively, are reported. Both species revealed elevated fluconazole and echinocandin MICs by the CLSI broth microdilution method. Additionally, B. serpentis exhibited high amphotericin B MICs, thus posing serious therapeutic challenges. PMID:25165080

  17. ARE INVASIVE RIPARIAN PLANTS ASSOCIATED WITH REDUCED BIOTIC CONDITION OF FAUNA IN WESTERN US STREAMS?

    EPA Science Inventory

    Yes. Records on the presence or absence of 12 invasive riparian plant taxa and observations on macroinvertebrate and vertebrate communities within streams were collected at over 1000 stream reaches. The sampled reaches were selected on a probability basis to represent the populat...

  18. No evolution of reduced resistance and compensation for psyllid herbivory by the invasive Genista monspessulana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The evolution of redirecting resources from plant defense to growth or reproduction may explain why some exotic species are successful invaders in new environments. For example, the evolution of increased competitive ability hypothesis (EICA) posits that escape from herbivores by invasive plants re...

  19. Toward the Neural Mechanisms of Reduced Working Memory Capacity in Schizophrenia

    PubMed Central

    Leonard, Carly J.; Kaiser, Sam T.; Robinson, Benjamin M.; Kappenman, Emily S.; Hahn, Britta; Gold, James M.; Luck, Steven J.

    2013-01-01

    People with schizophrenia (PSZ) demonstrate reliable reductions in working memory (WM) capacity (i.e., the number of objects that can be held in memory). The present study asked whether WM impairments in PSZ can be explained by the same neural mechanisms that underlie individual differences in WM capacity among healthy individuals. Specifically, we examined event-related potentials in PSZ and healthy matched controls during a change detection task that required the storage of multiple objects in WM. The amplitude of contralateral delay activity (CDA), which correlates with WM capacity in healthy individuals, was larger in controls than in PSZ for memory loads of 3 and 5 objects, but larger in PSZ than in controls for a memory load of 1. This same pattern was found in the subgroups of PSZ and controls with an equivalent WM capacity. Moreover, the increase in CDA amplitude was correlated with individual differences in capacity in controls, but not in PSZ. These results demonstrate that WM impairment in PSZ is not associated with the same patterns of neural activity that characterize low WM capacity in healthy individuals. We propose that WM impairment in PSZ instead reflects a specific impairment in the ability to distribute attention broadly. PMID:22661407

  20. Thermal and refining processes, not fermentation, tend to reduce lipotropic capacity of plant-based foods.

    PubMed

    Fardet, Anthony; Martin, Jean-François; Chardigny, Jean-Michel

    2011-08-01

    Plant-based foods (PBF) are relevant and diversified sources of lipotropes, which are compounds preventing excess hepatic fat deposits. In a first study, we defined the lipotropic capacity (LC, %) of raw PBF as the means of 8 lipotrope densities (LD, mg/100 kcal), each expressed relative to that of a reference food ranking the highest considering its mean 8 LD ranks (LC(raw asparagus)=100%) (A. Fardet, J.-F. Martin and J. M. Chardigny, J. Food Comp. Anal., 2011, DOI: 10.1016/j.jfca.2011.1003.1013). We showed that vegetables appeared as the best source of lipotropes on a 100 kcal-basis compared to legumes, cereals, fruits and nuts. The main objective of this second study was to quantify the effect of processing on LD and LC of raw PBF based on lipotrope contents collected in a USDA (United State Department of Agriculture) database and the literature, i.e. betaine, choline, myo-inositol, methionine, magnesium, niacin, pantothenic acid and folate contents. Choline and betaine densities were not significantly affected by processing while methionine and lipotropic micronutrient densities were significantly decreased, especially for magnesium, pantothenate and folates. Myo-inositol density decreases were insignificant due to lower product number resulting from limited literature data. Lipotropic micronutrient densities were more affected by processing than other densities. Fermentations increased betaine (median change of +32%) and choline (+34%) densities. Canning and boiling vegetables increased choline densities (+26%). Globally, processing significantly reduced LC by ∼20%, fermentations being less drastic (median change of -5%) than refining (-33%) and thermal treatments (-16%). More specifically, canning increased LC of beetroot (536 vs 390%) and common bean (40 vs 36%) as fermentation towards LC grape (14 vs 7% for wine). Results were then mainly discussed based on percentages of lipotrope content changes on a dry-weight basis. Results of this study also showed

  1. Ampelopsin reduces the migration and invasion of ovarian cancer cells via inhibition of epithelial-to-mesenchymal transition.

    PubMed

    Liu, Tianfeng; Liu, Peishu; Ding, Feng; Yu, Nina; Li, Shihong; Wang, Surong; Zhang, Xiaofei; Sun, Xiangxiu; Chen, Ying; Wang, Feng; Zhao, Yunhe; Li, Bo

    2015-02-01

    Ampelopsin has displayed anticancer activity in several types of cancers. However, no evidence has been reported for the direct effect of ampelopsin on ovarian cancer cell migration and invasion, and the underling mechanisms have not yet been clearly established. The aim of the present study was to investigate the influence of ampelopsin on the migration and invasion of ovarian cancer. Proliferation and viability of the ovarian cancer cells were detected by MTT assay. Migration and invasion of the cells were detected, respectively, by scratch wound healing assay and Transwell assay. The expression levels of epithelial-to-mesenchymal transition (EMT) markers were detected at the protein level after stimulation with ampelopsin. Then, the expression levels of NF-κB and p-IκBα were detected with western blot analysis. Meanwhile, an inhibitor of NF-κB was used to investigate the effect of ampelopsin. Finally, the expression of Snail was also detected. Proliferation, migration and invasion of the A2780 cells were all inhibited following the application of ampelopsin. Ampelopsin upregulated E-cadherin and downregulated N-cadherin and vimentin in a concentration- and time-dependent manner. Ampelopsin also exerted its ability to suppress the nuclear translocation of the NF-κB pathway. Administration of the inhibitor BAY11-7082 confirmed the roles of NF-κB in the expression of EMT markers and its transcription factor. These results demonstrated that ampelopsin inhibited EMT and reduced the invasion of ovarian cancer cells via the NF-κB/Snail pathway. PMID:25502786

  2. Strengthening Community Capacity to Participate in Making Decisions to Reduce Disproportionate Environmental Exposures

    PubMed Central

    Pastor, Manuel; Israel, Barbara

    2011-01-01

    Environmental exposures impose a disproportionate health burden on low-income populations and communities of color. One contributing factor may be the obstacles such communities face to full participation in making policy decisions about environmental health. This study described and analyzed the characteristics that contributed to communities' capacity to participate in making environmental decisions and suggested steps public agencies could take to achieve more meaningful participation. By strengthening community capacity, advancing authentic participation, and building democratic power, it might be possible to alter current patterns of health inequities. Strengthening participation by working with communities to develop the capacities needed to be effective in such processes is a key role for local, state, and national environmental agencies. PMID:22021323

  3. Ecosystem engineering by invasive exotic beavers reduces in-stream diversity and enhances ecosystem function in Cape Horn, Chile.

    PubMed

    Anderson, Christopher B; Rosemond, Amy D

    2007-11-01

    Species invasions are of global significance, but predicting their impacts can be difficult. Introduced ecosystem engineers, however, provide an opportunity to test the underlying mechanisms that may be common to all invasive engineers and link relationships between changes in diversity and ecosystem function, thereby providing explanatory power for observed ecological patterns. Here we test specific predictions for an invasive ecosystem engineer by quantifying the impacts of habitat and resource modifications caused by North American beavers (Castor canadensis) on aquatic macroinvertebrate community structure and stream ecosystem function in the Cape Horn Biosphere Reserve, Chile. We compared responses to beavers in three habitat types: (1) forested (unimpacted) stream reaches, (2) beaver ponds, and (3) sites immediately downstream of beaver dams in four streams. We found that beaver engineering in ponds created taxonomically simplified, but more productive, benthic macroinvertebrate assemblages. Specifically, macroinvertebrate richness, diversity and number of functional feeding groups were reduced by half, while abundance, biomass and secondary production increased three- to fivefold in beaver ponds compared to forested sites. Reaches downstream of beaver ponds were very similar to natural forested sections. Beaver invasion effects on both community and ecosystem parameters occurred predominantly via increased retention of fine particulate organic matter, which was associated with reduced macroinvertebrate richness and diversity (via homogenization of benthic microhabitat) and increased macroinvertebrate biomass and production (via greater food availability). Beaver modifications to macroinvertebrate community structure were largely confined to ponds, but increased benthic production in beaver-modified habitats adds to energy retention and flow for the entire stream ecosystem. Furthermore, the effects of beavers on taxa richness (negative) and measures of

  4. Diosgenin, a Steroidal Saponin, Inhibits Migration and Invasion of Human Prostate Cancer PC-3 Cells by Reducing Matrix Metalloproteinases Expression

    PubMed Central

    Chen, Pin-Shern; Shih, Yuan-Wei; Huang, Hsiang-Ching; Cheng, Hsing-Wen

    2011-01-01

    Background Diosgenin, a steroidal saponin obtained from fenugreek (Trigonella foenum graecum), was found to exert anti-carcinogenic properties, such as inhibiting proliferation and inducing apoptosis in a variety of tumor cells. However, the effect of diosgenin on cancer metastasis remains unclear. The aim of the study is to examine the effect of diosgenin on migration and invasion in human prostate cancer PC-3 cells. Methods and Principal Findings Diosgenin inhibited proliferation of PC-3 cells in a dose-dependent manner. When treated with non-toxic doses of diosgenin, cell migration and invasion were markedly suppressed by in vitro wound healing assay and Boyden chamber invasion assay, respectively. Furthermore, diosgenin reduced the activities of matrix metalloproteinase-2 (MMP-2) and MMP-9 by gelatin zymography assay. The mRNA level of MMP-2, -9, -7 and extracellular inducer of matrix metalloproteinase (EMMPRIN) were also suppressed while tissue inhibitor of metalloproteinase-2 (TIMP-2) was increased by diosgenin. In addition, diosgenin abolished the expression of vascular endothelial growth factor (VEGF) in PC-3 cells and tube formation of endothelial cells. Our immunoblotting assays indicated that diosgenin potently suppressed the phosphorylation of phosphatidylinositide-3 kinase (PI3K), Akt, extracellular signal regulating kinase (ERK) and c-Jun N-terminal kinase (JNK). In addition, diosgenin significantly decreased the nuclear level of nuclear factor kappa B (NF-κB), suggesting that diosgenin inhibited NF-κB activity. Conclusion/Significance The results suggested that diosgenin inhibited migration and invasion of PC-3 cells by reducing MMPs expression. It also inhibited ERK, JNK and PI3K/Akt signaling pathways as well as NF-κB activity. These findings reveal new therapeutic potential for diosgenin in anti-metastatic therapy. PMID:21629786

  5. Increased Inter-Colony Fusion Rates Are Associated with Reduced COI Haplotype Diversity in an Invasive Colonial Ascidian Didemnum vexillum

    PubMed Central

    Smith, Kirsty F.; Stefaniak, Lauren; Saito, Yasunori; Gemmill, Chrissen E. C.; Cary, S. Craig; Fidler, Andrew E.

    2012-01-01

    Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species. PMID:22303442

  6. The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells.

    PubMed

    Qualtrough, David; Rees, Phil; Speight, Beverley; Williams, Ann C; Paraskeva, Christos

    2015-01-01

    Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH) signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist) associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, Cancers 2015, 7 1886 these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer. PMID:26393651

  7. Parthenolide reduces the frequency of ABCB5-positive cells and clonogenic capacity of melanoma cells from anchorage independent melanospheres

    PubMed Central

    Czyz, Malgorzata; Koprowska, Kamila; Sztiller-Sikorska, Malgorzata

    2013-01-01

    Growing evidence suggests that the cancer stem cell phenotype in melanoma is dynamically regulated. Therefore, effective therapies have to target simultaneously bulk tumor cells and melanoma stem-like cells. The aim of the present study was to investigate the effects of parthenolide on heterogeneous cancer cell populations from anchorage-independent melanospheres. Cells derived from nodular melanoma specimens were grown under serum-free sphere-forming conditions. The effects of parthenolide on cellular viability, immunophenotype and self-renewing capacity were assessed with cells from dissociated melanospheres. Its penetration capacity was evaluated with intact melanospheres. In melanoma cells that survived treatment with parthenolide, a different immunophenotype than that in untreated control was found. The frequency of cells expressing the ABCB5 transporter was markedly reduced. Most importantly, melanoma cells that survived parthenolide treatment lost their self-renewing capacity. Significantly lower influence of drug on cellular viability and frequency of ABCB5-positive cells was observed in intact melanospheres. The potential clinical significance of our findings is based on the ability of parthenolide to affect both bulk and melanoma stem-like cells with clonogenic capacity and high expression of the ABCB5 transporter. Its low penetration capacity, however, may limit its action to easily accessible melanoma cells, either circulating in the blood or those in the vicinity to blood vessels within the tumor. Because of limited penetration capacity of parthenolide, this drug should be further explored as a part of multimodal therapies rather than as a stand-alone therapeutic agent. PMID:23192276

  8. Might Flowers of Invasive Plants Increase Native Bees Carrying Capacity? Intimations from Capitol Reef National Park, Utah

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We compared the native bees visiting the flowers of three species of invasive plants (Tamarix spp., Melilotus albus, M. officinalis) with those visiting seven native plant species in mid-summer at three sites in Capitol Reef National Park, UT, USA. Overall, as many species of bees visited the flowe...

  9. Impaired Semantic Knowledge Underlies the Reduced Verbal Short-Term Storage Capacity in Alzheimer's Disease

    ERIC Educational Resources Information Center

    Peters, Frederic; Majerus, Steve; De Baerdemaeker, Julie; Salmon, Eric; Collette, Fabienne

    2009-01-01

    A decrease in verbal short-term memory (STM) capacity is consistently observed in patients with Alzheimer's disease (AD). Although this impairment has been mainly attributed to attentional deficits during encoding and maintenance, the progressive deterioration of semantic knowledge in early stages of AD may also be an important determinant of poor…

  10. Self-Disorders in Individuals with Autistic Traits: Contribution of Reduced Autobiographical Reasoning Capacities

    ERIC Educational Resources Information Center

    Berna, Fabrice; Göritz, Anja S.; Schröder, Johanna; Coutelle, Romain; Danion, Jean-Marie; Cuervo-Lombard, Christine V.; Moritz, Steffen

    2016-01-01

    The present web-based study (N = 840) aimed to illuminate the cognitive mechanisms underlying self-disorders in autism. Initially, participants selected three self-defining memories. Then, we assessed their capacity to give meaning to these events (i.e., meaning making), their tendency to scrutinize autobiographical memory to better understand…

  11. Invasive parasites, habitat change and heavy rainfall reduce breeding success in Darwin's finches.

    PubMed

    Cimadom, Arno; Ulloa, Angel; Meidl, Patrick; Zöttl, Markus; Zöttl, Elisabet; Fessl, Birgit; Nemeth, Erwin; Dvorak, Michael; Cunninghame, Francesca; Tebbich, Sabine

    2014-01-01

    Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea) and the sympatric small tree finch (Camarhynchus parvulus), on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundance)is lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss. PMID:25248092

  12. Invasive Parasites, Habitat Change and Heavy Rainfall Reduce Breeding Success in Darwin's Finches

    PubMed Central

    Cimadom, Arno; Ulloa, Angel; Meidl, Patrick; Zöttl, Markus; Zöttl, Elisabet; Fessl, Birgit; Nemeth, Erwin; Dvorak, Michael; Cunninghame, Francesca; Tebbich, Sabine

    2014-01-01

    Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea) and the sympatric small tree finch (Camarhynchus parvulus), on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundance)is lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss. PMID:25248092

  13. Factors Predicting and Reducing Mortality in Patients with Invasive Staphylococcus aureus Disease in a Developing Country

    PubMed Central

    Nickerson, Emma K.; Wuthiekanun, Vanaporn; Wongsuvan, Gumphol; Limmathurosakul, Direk; Srisamang, Pramot; Mahavanakul, Weera; Thaipadungpanit, Janjira; Shah, Krupal R.; Arayawichanont, Arkhom; Amornchai, Premjit; Thanwisai, Aunchalee; Day, Nicholas P.; Peacock, Sharon J.

    2009-01-01

    Background Invasive Staphylococcus aureus infection is increasingly recognised as an important cause of serious sepsis across the developing world, with mortality rates higher than those in the developed world. The factors determining mortality in developing countries have not been identified. Methods A prospective, observational study of invasive S. aureus disease was conducted at a provincial hospital in northeast Thailand over a 1-year period. All-cause and S. aureus-attributable mortality rates were determined, and the relationship was assessed between death and patient characteristics, clinical presentations, antibiotic therapy and resistance, drainage of pus and carriage of genes encoding Panton-Valentine Leukocidin (PVL). Principal Findings A total of 270 patients with invasive S. aureus infection were recruited. The range of clinical manifestations was broad and comparable to that described in developed countries. All-cause and S. aureus-attributable mortality rates were 26% and 20%, respectively. Early antibiotic therapy and drainage of pus were associated with a survival advantage (both p<0.001) on univariate analysis. Patients infected by a PVL gene-positive isolate (122/248 tested, 49%) had a strong survival advantage compared with patients infected by a PVL gene-negative isolate (all-cause mortality 11% versus 39% respectively, p<0.001). Multiple logistic regression analysis using all variables significant on univariate analysis revealed that age, underlying cardiac disease and respiratory infection were risk factors for all-cause and S. aureus-attributable mortality, while one or more abscesses as the presenting clinical feature and procedures for infectious source control were associated with survival. Conclusions Drainage of pus and timely antibiotic therapy are key to the successful management of S. aureus infection in the developing world. Defining the presence of genes encoding PVL provides no practical bedside information and draws attention

  14. Daucus carota Pentane/Diethyl Ether Fraction Inhibits Motility and Reduces Invasion of Cancer Cells.

    PubMed

    Zgheib, Perla; Daher, Costantine F; Mroueh, Mohamad; Nasrallah, Anita; Taleb, Robin I; El-Sibai, Mirvat

    2014-01-01

    Daucus carota (DC) is a herb used in folklore medicine in Lebanon to treat numerous diseases including cancer. Recent studies in our laboratory on DC oil and its fractions revealed potent anticancer activities in vitro and in vivo. The present study aims to investigate the effect of the most potent DC fraction, pentane/diethyl ether (50:50), on lung, skin, breast and glioblastoma cancer cell motility and invasion. Upon treatment, a pronounced decrease in cancer cell motility was observed in the 4 cell lines. The treatment also led to a decrease in cancer cell invasion and an increased cell adhesion. Additionally, the DC fraction caused a decrease in the activation of the ρ-GTPases Rac and CDC42, a finding that may partially explain the treatment-induced decrease in cell motility. The current study demonstrates a crucial effect of the DC pentane/diethyl ether fraction on cancer cell motility and metastasis, making it a potential candidate for cancer therapy specifically targeting cancer motility and metastasis. PMID:26088465

  15. Non-anti-mitotic concentrations of taxol reduce breast cancer cell invasiveness

    SciTech Connect

    Tran, Truong-An; Gillet, Ludovic; Roger, Sebastien; Besson, Pierre; White, Edward; Le Guennec, Jean-Yves

    2009-02-06

    Taxol is widely used in breast cancer chemotherapy. Its effects are primarily attributed to its anti-mitotic activity. Microtubule perturbators also exert antimetastatic activities which cannot be explained solely by the inhibition of proliferation. Voltage-dependent sodium channels (Na{sub V}) are abnormally expressed in the highly metastatic breast cancer cell line MDA-MB-231 and not in MDA-MB-468 cell line. Inhibiting Na{sub V} activity with tetrodotoxin is responsible for an approximately 0.4-fold reduction of MDA-MB-231 cell invasiveness. In this study, we focused on the effect of a single, 2-h application of 10 nM taxol on the two cell lines MDA-MB-231 and MDA-MB-468. At this concentration, taxol had no effect on proliferation after 7 days and on migration in any cell line. However it led to a 40% reduction of transwell invasion of MDA-MB-231 cells. There was no additive effect when taxol and tetrodotoxin were simultaneously applied. Na{sub V} activity, as assessed by patch-clamp, indicates that it was changed by taxol pre-treatment. We conclude that taxol can exert anti-tumoral activities, in cells expressing Na{sub V}, at low doses that have no effect on cell proliferation. This effect might be due to a modulation of signalling pathways involving sodium channels.

  16. Deletion of a Malaria Invasion Gene Reduces Death and Anemia, in Model Hosts

    PubMed Central

    Gómez, Noé D.; Safeukui, Innocent; Adelani, Aanuoluwa A.; Tewari, Rita; Reddy, Janardan K.; Rao, Sam; Holder, Anthony; Buffet, Pierre; Mohandas, Narla; Haldar, Kasturi

    2011-01-01

    Malaria parasites induce complex cellular and clinical phenotypes, including anemia, cerebral malaria and death in a wide range of mammalian hosts. Host genes and parasite ‘toxins’ have been implicated in malarial disease, but the contribution of parasite genes remains to be fully defined. Here we assess disease in BALB/c mice and Wistar rats infected by the rodent malaria parasite Plasmodium berghei with a gene knock out for merozoite surface protein (MSP) 7. MSP7 is not essential for infection but in P. falciparum, it enhances erythrocyte invasion by 20%. In vivo, as compared to wild type, the P. berghei Δmsp7 mutant is associated with an abrogation of death and a decrease from 3% to 2% in peak, circulating parasitemia. The Δmsp7 mutant is also associated with less anemia and modest increase in the size of follicles in the spleen. Together these data show that deletion of a single parasite invasion ligand modulates blood stage disease, as measured by death and anemia. This work is the first to assess the contribution of a gene present in all plasmodial species in severe disease. PMID:21980474

  17. Reduced density and nest survival of ground-nesting songbirds relative to earthworm invasions in northern hardwood forests.

    PubMed

    Loss, Scott R; Blair, Robert B

    2011-10-01

    European earthworms (Lumbricus spp.) are spreading into previously earthworm-free forests in the United States and Canada and causing substantial changes, including homogenization of soil structure, removal of the litter layer, and reduction in arthropod abundance and species richness of understory plants. Whether these changes affect songbirds that nest and forage on the forest floor is unknown. In stands with and without earthworms in the Chequamegon-Nicolet National Forest, Wisconsin (U.S.A.), we surveyed for, monitored nests of, and measured attributes of habitat of Ovenbirds (Seiurus aurocapillus) and Hermit Thrushes (Catharus guttatus), both ground-dwelling songbirds, and we sampled earthworms at survey points and nests. Bird surveys indicated significantly lower densities of Ovenbirds and Hermit Thrushes in relation to Lumbricus invasions at survey point and stand extents (3.1 and 15-20 ha, respectively). Modeling of Ovenbird nest survival (i.e., the probability that nestlings successfully fledge) indicated that lower survival probabilities were associated with increased sedge cover and decreased litter depth, factors that are related to Lumbricus invasions, possibly due to reduced nest concealment or arthropod abundance. Our findings provide compelling evidence that earthworm invasions may be associated with local declines of forest songbird populations. PMID:21797927

  18. Impaired Contingent Attentional Capture Predicts Reduced Working Memory Capacity in Schizophrenia

    PubMed Central

    Mayer, Jutta S.; Fukuda, Keisuke; Vogel, Edward K.; Park, Sohee

    2012-01-01

    Although impairments in working memory (WM) are well documented in schizophrenia, the specific factors that cause these deficits are poorly understood. In this study, we hypothesized that a heightened susceptibility to attentional capture at an early stage of visual processing would result in working memory encoding problems. 30 patients with schizophrenia and 28 demographically matched healthy participants were presented with a search array and asked to report the orientation of the target stimulus. In some of the trials, a flanker stimulus preceded the search array that either matched the color of the target (relevant-flanker capture) or appeared in a different color (irrelevant-flanker capture). Working memory capacity was determined in each individual using the visual change detection paradigm. Patients needed considerably more time to find the target in the no-flanker condition. After adjusting the individual exposure time, both groups showed equivalent capture costs in the irrelevant-flanker condition. However, in the relevant-flanker condition, capture costs were increased in patients compared to controls when the stimulus onset asynchrony between the flanker and the search array was high. Moreover, the increase in relevant capture costs correlated negatively with working memory capacity. This study demonstrates preserved stimulus-driven attentional capture but impaired contingent attentional capture associated with low working memory capacity in schizophrenia. These findings suggest a selective impairment of top-down attentional control in schizophrenia, which may impair working memory encoding. PMID:23152783

  19. Risk of COPD with obstruction in active smokers with normal spirometry and reduced diffusion capacity.

    PubMed

    Harvey, Ben-Gary; Strulovici-Barel, Yael; Kaner, Robert J; Sanders, Abraham; Vincent, Thomas L; Mezey, Jason G; Crystal, Ronald G

    2015-12-01

    Smokers are assessed for chronic obstructive pulmonary disease (COPD) using spirometry, with COPD defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) as airflow limitation that is not fully reversible with bronchodilators. There is a subset of smokers with normal spirometry (by GOLD criteria), who have a low diffusing capacity of the lung for carbon monoxide (DLCO), a parameter linked to emphysema and small airway disease. The natural history of these "normal spirometry/low DLCO" smokers is unknown.From a cohort of 1570 smokers in the New York City metropolitian area, all of whom had normal spirometry, two groups were randomly selected for lung function follow-up: smokers with normal spirometry/normal DLCO (n=59) and smokers with normal spirometry/low DLCO (n=46). All had normal history, physical examination, complete blood count, urinalysis, HIV status, α1-antitrypsin level, chest radiography, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC ratio and total lung capacity. Throughout the study, all continued to be active smokers.In the normal spirometry/normal DLCO group assessed over 45±20 months, 3% developed GOLD-defined COPD. In contrast, in the normal spirometry/low DLCO group, followed over 41±31 months, 22% developed GOLD-defined COPD.Despite appearing "normal" according to GOLD, smokers with normal spirometry but low DLCO are at significant risk of developing COPD with obstruction to airflow. PMID:26541521

  20. Fortune favours the bold: a higher predator reduces the impact of a native but not an invasive intermediate predator.

    PubMed

    Barrios-O'Neill, Daniel; Dick, Jaimie T A; Emmerson, Mark C; Ricciardi, Anthony; MacIsaac, Hugh J; Alexander, Mhairi E; Bovy, Helene C

    2014-05-01

    Emergent multiple predator effects (MPEs) might radically alter predictions of predatory impact that are based solely on the impact of individuals. In the context of biological invasions, determining if and how the individual-level impacts of invasive predators relates to their impacts in multiple-individual situations will inform understanding of how such impacts might propagate through recipient communities. Here, we use functional responses (the relationship between prey consumption rate and prey density) to compare the impacts of the invasive freshwater mysid crustacean Hemimysis anomala with a native counterpart Mysis salemaai when feeding on basal cladoceran prey (i) as individuals, (ii) in conspecific groups and (iii) in conspecific groups in the presence of a higher fish predator, Gasterosteus aculeatus. In the absence of the higher predator, the invader consumed significantly more basal prey than the native, and consumption was additive for both mysid species - that is, group consumption was predictable from individual-level consumption. Invaders and natives were themselves equally susceptible to predation when feeding with the higher fish predator, but an MPE occurred only between the natives and higher predator, where consumption of basal prey was significantly reduced. In contrast, consumption by the invaders and higher predator remained additive. The presence of a higher predator serves to exacerbate the existing difference in individual-level consumption between invasive and native mysids. We attribute the mechanism responsible for the MPE associated with the native to a trait-mediated indirect interaction, and further suggest that the relative indifference to predator threat on the part of the invader contributes to its success and impacts within invaded communities. PMID:24117414

  1. Extreme drought event and shrub invasion combine to reduce ecosystem functioning and resilience in water-limited climates

    NASA Astrophysics Data System (ADS)

    Caldeira, Maria; Lecomte, Xavier; David, Teresa; Pinto, Joaquim; Bugalho, Miguel; Werner, Christiane

    2016-04-01

    Extreme droughts and plant invasions are major drivers of global change that can critically affect ecosystem functioning. Shrub encroachment is increasing in many regions worldwide and extreme events are projected to increase in frequency and intensity, namely in the Mediterranean region. Nevertheless, little is known about how these drivers may interact and affect ecosystem functioning and resilience to extreme droughts. Using a manipulative shrub removal experiment and the co-occurrence of an extreme drought event (2011/2012) in a Mediterranean woodland, we show that the native shrub invasion and extreme drought combined to reduce ecosystem transpiration and the resilience of the key-stone oak tree species. We established six 25 x 25 m paired plots in a shrub (Cistus ladanifer L.) encroached Mediterranean cork-oak (Quercus suber L.) woodland. We measured sapflow and pre-dawn leaf water potential of trees and shrubs and soil water content in all plots during three years. We determined the resilience of tree transpiration to evaluate to what extent trees recovered from the extreme drought event. From February to November 2011 we conducted baseline measurements for plot comparison. In November 2011 all the shrubs from one of all the paired plots were cut and removed. Ecosystem transpiration was dominated by the water use of the invasive shrub, which further increased after the extreme drought. Simultaneously, tree transpiration in invaded plots declined much stronger (67 ± 13 %) than in plots cleared from shrubs (31 ± 11%) relative to the pre-drought year. Trees in invaded plots were not able to recover in the following wetter year showing lower resilience to the extreme drought event. Our results imply that in Mediterranean-type of climates invasion by water spending species can combine with projected recurrent extreme droughts causing critical drought tolerance thresholds of trees to be overcome increasing the probability of tree mortality (Caldeira et.al. 2015

  2. Increased invasion and tumorigenicity capacity of CD44+/CD24- breast cancer MCF7 cells in vitro and in nude mice

    PubMed Central

    2013-01-01

    Background Identification of cancer stem cells (CSCs) and their behaviors will provide insightful information for the future control of human cancers. This study investigated CD44 and CD24 cell surface markers as breast cancer CSC markers in vitro and in vivo. Methods Flow cytometry with CD44 and CD24 markers was used to sort breast cancer MCF7 cells for scanning electron microscopy (SEM), tumor cell invasion assay, and nude mouse xenograft assay. Results Flow cytometry assay using CD44 and CD24 markers sorted MCF7 cells into four subsets, i.e., CD44+/CD24-/low, CD44-/CD24+, CD44+/CD24+, and CD44-/CD24-. The SEM data showed that there were many protrusions on the surface of CD44+/CD24-/low cells. CD44+/CD24-/low cells had many microvilli and pseudopodia. The CD44+/CD24-/low cells had a higher migration and invasion abilities than that of the other three subsets of the cells. The in vivo tumor formation assay revealed that CD44+/CD24- cells had the highest tumorigenic capacity compared to the other three subsets. Conclusion CD44 and CD24 could be useful markers for identification of breast CSCs because CD44+/CD24-/low cells had unique surface ultrastructures and the highest tumorigenicity and invasive abilities. PMID:23799994

  3. Gesturing during mental problem solving reduces eye movements, especially for individuals with lower visual working memory capacity.

    PubMed

    Pouw, Wim T J L; Mavilidi, Myrto-Foteini; van Gog, Tamara; Paas, Fred

    2016-08-01

    Non-communicative hand gestures have been found to benefit problem-solving performance. These gestures seem to compensate for limited internal cognitive capacities, such as visual working memory capacity. Yet, it is not clear how gestures might perform this cognitive function. One hypothesis is that gesturing is a means to spatially index mental simulations, thereby reducing the need for visually projecting the mental simulation onto the visual presentation of the task. If that hypothesis is correct, less eye movements should be made when participants gesture during problem solving than when they do not gesture. We therefore used mobile eye tracking to investigate the effect of co-thought gesturing and visual working memory capacity on eye movements during mental solving of the Tower of Hanoi problem. Results revealed that gesturing indeed reduced the number of eye movements (lower saccade counts), especially for participants with a relatively lower visual working memory capacity. Subsequent problem-solving performance was not affected by having (not) gestured during the mental solving phase. The current findings suggest that our understanding of gestures in problem solving could be improved by taking into account eye movements during gesturing. PMID:26993293

  4. Microparticles Mediate the Intercellular Regulation of microRNA-503 and Proline-Rich Tyrosine Kinase 2 to Alter the Migration and Invasion Capacity of Breast Cancer Cells

    PubMed Central

    Gong, Joyce; Luk, Frederick; Jaiswal, Ritu; Bebawy, Mary

    2014-01-01

    The successful treatment of cancer is hampered by drug resistance and metastasis. While these two obstacles were once considered separately, recent evidence associates resistance with an enhanced metastatic capacity. However, the underlying mechanisms remain undefined. We previously described the intercellular transfer of drug resistance via submicron vesicles called microparticles (MPs). We now propose that MPs derived from drug-resistant cells are also involved in the intercellular transfer of components to enhance the migration and invasion capacity of cells. Thus, MPs may be a conduit between resistance and metastasis. We used microarray analysis to identify regulatory microRNAs (miRNAs), which contribute to the dissemination of metastatic traits. miR-503 was downregulated in recipient cells following co-culture with MPs isolated from drug-resistant cells. miR-503 was inversely associated with metastasis, as demonstrated using wound healing/scratch migration assays and Matrigel®-coated transwell invasion assays. Proline-rich tyrosine kinase 2 (PYK2) was upregulated in recipient cells and associated with increased migration and invasion, with these phenotypes being reversed using a pharmacological inhibitor of PYK2 phosphorylation, tyrphostin A9. However, the MP-mediated promotion of metastatic traits was not due to the presence of these effectors in the MP cargo but rather due to down stream effector molecules in these pathways. This is the first demonstration that the role of MPs in trait acquisition extends beyond the direct transfer of vesicle components and also includes transfer of intermediary regulators that induce down stream mediators following transfer to recipient cells. This implicates an expanding role of MPs in cancer pathogenesis. PMID:25177548

  5. Invasive Salmonella Typhimurium ST313 with Naturally Attenuated Flagellin Elicits Reduced Inflammation and Replicates within Macrophages

    PubMed Central

    Ramachandran, Girish; Perkins, Darren J.; Schmidlein, Patrick J.; Tulapurkar, Mohan E.; Tennant, Sharon M.

    2015-01-01

    Invasive non-typhoidal Salmonella (iNTS) are an important cause of septicemia in children under the age of five years in sub-Saharan Africa. A novel genotype of Salmonella enterica subsp. enterica serovar Typhimurium (multi-locus sequence type [ST] 313) circulating in this geographic region is genetically different to from S. Typhimurium ST19 strains that are common throughout the rest of the world. S. Typhimurium ST313 strains have acquired pseudogenes and genetic deletions and appear to be evolving to become more like the typhoidal serovars S. Typhi and S. Paratyphi A. Epidemiological and clinical data show that S. Typhimurium ST313 strains are clinically associated with invasive systemic disease (bacteremia, septicemia, meningitis) rather than with gastroenteritis. The current work summarizes investigations of the broad hypothesis that S. Typhimurium ST313 isolates from Mali, West Africa, will behave differently from ST19 isolates in various in vitro assays. Here, we show that strains of the ST313 genotype are phagocytosed more efficiently and are highly resistant to killing by macrophage cell lines and primary mouse and human macrophages compared to ST19 strains. S. Typhimurium ST313 strains survived and replicated within different macrophages. Infection of macrophages with S. Typhimurium ST19 strains resulted in increased apoptosis and higher production of proinflammatory cytokines, as measured by gene expression and protein production, compared to S. Typhimurium ST313 strains. This difference in proinflammatory cytokine production and cell death between S. Typhimurium ST19 and ST313 strains could be explained, in part, by an increased production of flagellin by ST19 strains. These observations provide further evidence that S. Typhimurium ST313 strains are phenotypically different to ST19 strains and instead share similar pathogenic characteristics with typhoidal Salmonella serovars. PMID:25569606

  6. Psychosis as a disorder of reduced cathectic capacity: Freud's analysis of the Schreber case revisited.

    PubMed

    McGlashan, Thomas H

    2009-05-01

    Approximately 100 years ago, a prominent German public figure name Daniel Schreber wrote memoirs of his experiences in asylums. His case was diagnosed Dementia Praecox at times and Paranoia at others by his treaters. Freud analyzed Schreber's memoirs from the perspective of his "libido" theory of developmentally organized mental "cathexes" or ideational/emotional investments in self and others. Revisiting Freud's analysis of the Schreber case suggests that it may represent the first theoretical articulation that the pathophysiologic core of psychosis is one of deficit, i.e., of diminished (organic) cathectic capacity for normal mental and affective investments in life. PMID:19357240

  7. Low-Dose Paclitaxel Reduces S100A4 Nuclear Import to Inhibit Invasion and Hematogenous Metastasis of Cholangiocarcinoma.

    PubMed

    Cadamuro, Massimiliano; Spagnuolo, Gaia; Sambado, Luisa; Indraccolo, Stefano; Nardo, Giorgia; Rosato, Antonio; Brivio, Simone; Caslini, Chiara; Stecca, Tommaso; Massani, Marco; Bassi, Nicolò; Novelli, Eugenio; Spirli, Carlo; Fabris, Luca; Strazzabosco, Mario

    2016-08-15

    Nuclear expression of the calcium-binding protein S100A4 is a biomarker of increased invasiveness in cholangiocarcinoma, a primary liver cancer with scarce treatment opportunities and dismal prognosis. In this study, we provide evidence that targeting S100A4 nuclear import by low-dose paclitaxel, a microtubule-stabilizing agent, inhibits cholangiocarcinoma invasiveness and metastatic spread. Administration of low-dose paclitaxel to established (EGI-1) and primary (CCA-TV3) cholangiocarcinoma cell lines expressing nuclear S100A4 triggered a marked reduction in nuclear expression of S100A4 without modifying its cytoplasmic levels, an effect associated with a significant decrease in cell migration and invasiveness. While low-dose paclitaxel did not affect cellular proliferation, apoptosis, or cytoskeletal integrity, it significantly reduced SUMOylation of S100A4, a critical posttranslational modification that directs its trafficking to the nucleus. This effect of low-dose paclitaxel was reproduced by ginkolic acid, a specific SUMOylation inhibitor. Downregulation of nuclear S100A4 by low-dose paclitaxel was associated with a strong reduction in RhoA and Cdc42 GTPase activity, MT1-MMP expression, and MMP-9 secretion. In an SCID mouse xenograft model, low-dose metronomic paclitaxel treatment decreased lung dissemination of EGI-1 cells without significantly affecting their local tumor growth. In the tumor mass, nuclear S100A4 expression by cholangiocarcinoma cells was significantly reduced, whereas rates of proliferation and apoptosis were unchanged. Overall, our findings highlight nuclear S100A4 as a candidate therapeutic target in cholangiocarcinoma and establish a mechanistic rationale for the use of low-dose paclitaxel in blocking metastatic progression of cholangiocarcinoma. Cancer Res; 76(16); 4775-84. ©2016 AACR. PMID:27328733

  8. HDL phospholipid content and cholesterol efflux capacity are reduced in patients with very high HDL-C and coronary disease

    PubMed Central

    Agarwala, Anandita P.; Rodrigues, Amrith; Risman, Marjorie; McCoy, Mary; Trindade, Kevin; Qu, Liming; Cuchel, Marina; Billheimer, Jeffrey; Rader, Daniel J.

    2015-01-01

    Objective Plasma levels of high-density lipoprotein cholesterol (HDL-C) are strongly inversely associated with coronary artery disease (CAD), and high HDL-C is generally associated with reduced risk of CAD. Extremely high HDL-C with CAD is an unusual phenotype, and we hypothesized that the HDL in such individuals may have an altered composition and reduced function when compared to controls with similarly high HDL-C and no CAD. Approach 55 subjects with very high HDL-C (mean 86 mg/dL) and onset of CAD around age 60 with no known risk factors for CAD (‘cases’) were identified through systematic recruitment. 120 control subjects without CAD, matched for race, gender, and HDL-C level (‘controls’), were identified. In all subjects, HDL composition was analyzed and HDL cholesterol efflux capacity was assessed. Results HDL phospholipid composition was significantly lower in cases (92 ± 37 mg/dL) than in controls (109 ± 43 mg/dL, p= 0.0095). HDL cholesterol efflux capacity was significantly lower in cases (1.96 ± 0.39) compared with controls (2.11 ± 0.43, p= 0.04). Conclusions In persons with very high HDL-C, reduced HDL phospholipid content and cholesterol efflux capacity is associated with the paradoxical development of CAD. PMID:25838421

  9. Reducing the Cation Exchange Capacity of Lithium Clay to Form Better Dispersed Polymer-Clay Nanocomposites

    NASA Technical Reports Server (NTRS)

    Liang, Maggie

    2004-01-01

    Polymer-clay nanocomposites have exhibited superior strength and thermo- oxidative properties as compared to pure polymers for use in air and space craft; however, there has often been difficulty completely dispersing the clay within the matrices of the polymer. In order to improve this process, the cation exchange capacity of lithium clay is first lowered using twenty-four hour heat treatments of no heat, 130 C, 150 C, or 170 C to fixate the lithium ions within the clay layers so that they are unexchangeable. Generally, higher temperatures have generated lower cation exchange capacities. An ion exchange involving dodecylamine, octadecylamine, or dimethyl benzidine (DMBZ) is then employed to actually expand the clay galleries. X-ray diffraction and transmission electron microscopy can be used to determine whether the clay has been successfully exfoliated. Finally, resins of DMBZ with clay are then pressed into disks for characterization using dynamic mechanical analyzer and oven- aging techniques in order to evaluate their glass transition, modulus strength, and thermal-oxidative stability in comparison to neat DMBZ. In the future, they may also be tested as composites for flexural and laminar shear strength.

  10. Search for Expectancy-Inconsistent Information Reduces Uncertainty Better: The Role of Cognitive Capacity.

    PubMed

    Strojny, Paweł; Kossowska, Małgorzata; Strojny, Agnieszka

    2016-01-01

    Motivation and cognitive capacity are key factors in people's everyday struggle with uncertainty. However, the exact nature of their interplay in various contexts still needs to be revealed. The presented paper reports on two experimental studies which aimed to examine the joint consequences of motivational and cognitive factors for preferences regarding incomplete information expansion. In Study 1 we demonstrate the interactional effect of motivation and cognitive capacity on information preference. High need for closure resulted in a stronger relative preference for expectancy-inconsistent information among non-depleted individuals, but the opposite among cognitively depleted ones. This effect was explained by the different informative value of questions in comparison to affirmative sentences and the potential possibility of assimilation of new information if it contradicts prior knowledge. In Study 2 we further investigated the obtained effect, showing that not only questions but also other kinds of incomplete information are subject to the same dependency. Our results support the expectation that, in face of incomplete information, motivation toward closure may be fulfilled efficiently by focusing on expectancy-inconsistent pieces of data. We discuss the obtained effect in the context of previous assumptions that high need for closure results in a simple processing style, advocating a more complex approach based on the character of the provided information. PMID:27047422

  11. Search for Expectancy-Inconsistent Information Reduces Uncertainty Better: The Role of Cognitive Capacity

    PubMed Central

    Strojny, Paweł; Kossowska, Małgorzata; Strojny, Agnieszka

    2016-01-01

    Motivation and cognitive capacity are key factors in people’s everyday struggle with uncertainty. However, the exact nature of their interplay in various contexts still needs to be revealed. The presented paper reports on two experimental studies which aimed to examine the joint consequences of motivational and cognitive factors for preferences regarding incomplete information expansion. In Study 1 we demonstrate the interactional effect of motivation and cognitive capacity on information preference. High need for closure resulted in a stronger relative preference for expectancy-inconsistent information among non-depleted individuals, but the opposite among cognitively depleted ones. This effect was explained by the different informative value of questions in comparison to affirmative sentences and the potential possibility of assimilation of new information if it contradicts prior knowledge. In Study 2 we further investigated the obtained effect, showing that not only questions but also other kinds of incomplete information are subject to the same dependency. Our results support the expectation that, in face of incomplete information, motivation toward closure may be fulfilled efficiently by focusing on expectancy-inconsistent pieces of data. We discuss the obtained effect in the context of previous assumptions that high need for closure results in a simple processing style, advocating a more complex approach based on the character of the provided information. PMID:27047422

  12. Transcriptional responses of invasive and indigenous whiteflies to different host plants reveal their disparate capacity of adaptation.

    PubMed

    Xu, Hong-Xing; Hong, Yue; Zhang, Min-Zhu; Wang, Yong-Liang; Liu, Shu-Sheng; Wang, Xiao-Wei

    2015-01-01

    The whitefly Bemisia tabaci contains more than 35 cryptic species. The higher adaptability of Middle East-Asia Minor 1 (MEAM1) cryptic species has been recognized as one important factor for its invasion and displacement of other indigenous species worldwide. Here we compared the performance of the invasive MEAM1 and the indigenous Asia II 3 whitefly species following host plant transfer from a suitable host (cotton) to an unsuitable host (tobacco) and analyzed their transcriptional responses. After transfer to tobacco for 24 h, MEAM1 performed much better than Asia II 3. Transcriptional analysis showed that the patterns of gene regulation were very different with most of the genes up-regulated in MEAM1 but down-regulated in Asia II 3. Whereas carbohydrate and energy metabolisms were repressed in Asia II 3, the gene expression and protein metabolisms were activated in MEAM1. Compared to the constitutive high expression of detoxification genes in MEAM1, most of the detoxification genes were down-regulated in Asia II 3. Enzymatic activities of P450, GST and esterase further verified that the detoxification of MEAM1 was much higher than that of Asia II 3. These results reveal obvious differences in responses of MEAM1 and Asia II 3 to host transfer. PMID:26041313

  13. A Hybrid Quorum Protocol for Improved Availability, Capacity, Load and Reduced Overhead

    NASA Astrophysics Data System (ADS)

    Pandey, Parul; Tripathi, Maheshwari

    2016-06-01

    Data replication is playing a vital role in the design of distributed information systems. This paper presents a novel and efficient distributed algorithm for managing replicated data and for better performance and availability. This paper presents an extension to existing wheel protocol for improved performance. Wheel protocol imposes a logical wheel structure on the set of copies of an object and gives smallest read quorum. In addition to small read quorum size for read intensive applications, it is necessary to have good write availability as well. This paper proposes two hybrid wheel protocols, which superimpose logarithmic and ring protocols on top of the wheel protocol. It shows that, both protocols help in improving write availability, read capacity, load and message overhead and also compare their performances with wheel and other protocols. Hybrid protocols expand usage of wheel protocol to different type of applications.

  14. Mitochondrial uncoupling reduces exercise capacity despite several skeletal muscle metabolic adaptations.

    PubMed

    Schlagowski, A I; Singh, F; Charles, A L; Gali Ramamoorthy, T; Favret, F; Piquard, F; Geny, B; Zoll, J

    2014-02-15

    The effects of mitochondrial uncoupling on skeletal muscle mitochondrial adaptation and maximal exercise capacity are unknown. In this study, rats were divided into a control group (CTL, n = 8) and a group treated with 2,4-dinitrophenol, a mitochondrial uncoupler, for 28 days (DNP, 30 mg·kg(-1)·day(-1) in drinking water, n = 8). The DNP group had a significantly lower body mass (P < 0.05) and a higher resting oxygen uptake (Vo2, P < 0.005). The incremental treadmill test showed that maximal running speed and running economy (P < 0.01) were impaired but that maximal Vo2 (Vo2max) was higher in the DNP-treated rats (P < 0.05). In skinned gastrocnemius fibers, basal respiration (V0) was higher (P < 0.01) in the DNP-treated animals, whereas the acceptor control ratio (ACR, Vmax/V0) was significantly lower (P < 0.05), indicating a reduction in OXPHOS efficiency. In skeletal muscle, DNP activated the mitochondrial biogenesis pathway, as indicated by changes in the mRNA expression of PGC1-α and -β, NRF-1 and -2, and TFAM, and increased the mRNA expression of cytochrome oxidase 1 (P < 0.01). The expression of two mitochondrial proteins (prohibitin and Ndufs 3) was higher after DNP treatment. Mitochondrial fission 1 protein (Fis-1) was increased in the DNP group (P < 0.01), but mitofusin-1 and -2 were unchanged. Histochemical staining for NADH dehydrogenase and succinate dehydrogenase activity in the gastrocnemius muscle revealed an increase in the proportion of oxidative fibers after DNP treatment. Our study shows that mitochondrial uncoupling induces several skeletal muscle adaptations, highlighting the role of mitochondrial coupling as a critical factor for maximal exercise capacities. These results emphasize the importance of investigating the qualitative aspects of mitochondrial function in addition to the amount of mitochondria. PMID:24336883

  15. Allocating surveillance resources to reduce ecological invasions: maximizing detections and information about the threat.

    PubMed

    Robinson, Andrew; Burgman, Mark A; Cannon, Rob

    2011-06-01

    Allocating resources to detect invasive pests, diseases, and pathogens on exposure pathways requires a trade-off between the need to detect as many contaminated items as possible and the need to acquire knowledge about contamination rates. We develop a model and an algorithm that provide guidance for the allocation of inspection resources across multiple dynamic pathways in cases where not every item can be inspected. The model uses a null hypothesis that the contamination rate of a pathway is above a specified level: a risk cutoff. Pathways with a risk above the cutoff are fully inspected, and those with a risk below the cutoff level are monitored at a rate that would detect a change of the risk to being above the cutoff level with high probability. We base our decision on the 95% upper confidence limit for the contamination rate. We demonstrate via simulations and a data set that focusing inspection resources on specific pathways can result in substantially more effective intervention, and that the reduction in overall effectiveness of monitoring low-risk pathways need not be substantial. Use of the model demands the selection of the risk cutoff, and this limit can be set according to projected consequences. PMID:21774439

  16. Reduced mitochondrial oxidative capacity and increased mitochondrial uncoupling impair myocardial energetics in obesity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is a risk factor for cardiovascular disease and is strongly associated with insulin resistance and type 2 diabetes. Recent studies in obese humans and animals demonstrated increased myocardial oxygen consumption (MVO2) and reduced cardiac efficiency (CE); however, the underlying mechanisms r...

  17. Dropping behaviour of pea aphid nymphs increases their development time and reduces their reproductive capacity as adults

    PubMed Central

    Agabiti, Barbara; Wassenaar, Roxanne J.

    2016-01-01

    Background. Many aphid species, including the pea aphid Acyrthosiphon pisum, exhibit a behaviour where they drop or fall from their host plant, a commonly used strategy to avoid predation, parasitism or physical disturbance. We hypothesised that there was a physiological non-consumptive cost due to such dropping behaviour because aphids would expend energy re-establishing themselves on a host plant and also lose feeding time. Methods. We evaluated this non-consumptive cost by determining the development time and reproductive potential of pea aphids that whilst developing as nymphs had regularly dropped to the ground following dislodgment from their host plant. Using a microcosm approach, in a replicated and balanced laboratory experiment, we caused aphid dropping behaviour by tapping the plants on which they were feeding. Results. The results demonstrated that disturbance by dropping behaviour increased nymphal development time and reduced their subsequent reproductive capacity as adults. Discussion. We conclude that dropping behaviour had a strong negative effect on the development of nymphs and their subsequent reproductive capacity. This implies that the physiological cost of such a behaviour choice is substantial, and that such avoidance strategies require a trade-off which reduces the capacity of a population to increase. PMID:27547545

  18. Dropping behaviour of pea aphid nymphs increases their development time and reduces their reproductive capacity as adults.

    PubMed

    Agabiti, Barbara; Wassenaar, Roxanne J; Winder, Linton

    2016-01-01

    Background. Many aphid species, including the pea aphid Acyrthosiphon pisum, exhibit a behaviour where they drop or fall from their host plant, a commonly used strategy to avoid predation, parasitism or physical disturbance. We hypothesised that there was a physiological non-consumptive cost due to such dropping behaviour because aphids would expend energy re-establishing themselves on a host plant and also lose feeding time. Methods. We evaluated this non-consumptive cost by determining the development time and reproductive potential of pea aphids that whilst developing as nymphs had regularly dropped to the ground following dislodgment from their host plant. Using a microcosm approach, in a replicated and balanced laboratory experiment, we caused aphid dropping behaviour by tapping the plants on which they were feeding. Results. The results demonstrated that disturbance by dropping behaviour increased nymphal development time and reduced their subsequent reproductive capacity as adults. Discussion. We conclude that dropping behaviour had a strong negative effect on the development of nymphs and their subsequent reproductive capacity. This implies that the physiological cost of such a behaviour choice is substantial, and that such avoidance strategies require a trade-off which reduces the capacity of a population to increase. PMID:27547545

  19. Crif1 Deficiency Reduces Adipose OXPHOS Capacity and Triggers Inflammation and Insulin Resistance in Mice

    PubMed Central

    Ryu, Min Jeong; Kim, Soung Jung; Kim, Yong Kyung; Choi, Min Jeong; Tadi, Surendar; Lee, Min Hee; Lee, Seong Eun; Chung, Hyo Kyun; Jung, Saet Byel; Kim, Hyun-Jin; Jo, Young Suk; Kim, Koon Soon; Lee, Sang-Hee; Kim, Jin Man; Kweon, Gi Ryang; Park, Ki Cheol; Lee, Jung Uee; Kong, Young Yun; Lee, Chul-Ho; Chung, Jongkyeong; Shong, Minho

    2013-01-01

    Impaired mitochondrial oxidative phosphorylation (OXPHOS) has been proposed as an etiological mechanism underlying insulin resistance. However, the initiating organ of OXPHOS dysfunction during the development of systemic insulin resistance has yet to be identified. To determine whether adipose OXPHOS deficiency plays an etiological role in systemic insulin resistance, the metabolic phenotype of mice with OXPHOS–deficient adipose tissue was examined. Crif1 is a protein required for the intramitochondrial production of mtDNA–encoded OXPHOS subunits; therefore, Crif1 haploinsufficient deficiency in mice results in a mild, but specific, failure of OXPHOS capacity in vivo. Although adipose-specific Crif1-haploinsufficient mice showed normal growth and development, they became insulin-resistant. Crif1-silenced adipocytes showed higher expression of chemokines, the expression of which is dependent upon stress kinases and antioxidant. Accordingly, examination of adipose tissue from Crif1-haploinsufficient mice revealed increased secretion of MCP1 and TNFα, as well as marked infiltration by macrophages. These findings indicate that the OXPHOS status of adipose tissue determines its metabolic and inflammatory responses, and may cause systemic inflammation and insulin resistance. PMID:23516375

  20. A Smac Mimetic Reduces TNF Related Apoptosis Inducing Ligand (TRAIL)-Induced Invasion and Metastasis of Cholangiocarcinoma Cells

    PubMed Central

    Fingas, Christian D.; Blechacz, Boris R. A.; Smoot, Rory L.; Guicciardi, Maria E.; Mott, Justin; Bronk, Steve F.; Werneburg, Nathan W.; Sirica, Alphonse E.; Gores, Gregory J.

    2010-01-01

    Cholangiocarcinoma (CCA) cells paradoxically express tumor necrosis factor–related apoptosis-inducing ligand (TRAIL), a death ligand that, failing to kill CCA cells, instead promotes their tumorigenicity and especially the metastatic behaviors of cell migration and invasion. Second mitochondria-derived activator of caspase (smac) mimetics are promising cancer therapeutic agents that enhance proapoptotic death receptor signaling by causing cellular degradation of inhibitor of apoptosis (IAP) proteins. Our aim was to examine the in vitro and in vivo effects of the smac mimetic JP1584 in CCA. Despite JP1584-mediated loss of cellular inhibitor of apoptosis-1 (cIAP-1) and cIAP-2, TRAIL failed to induce apoptosis in KMCH-1, TFK-1, and BDEneu CCA cells; a finding consistent with a downstream block in death signaling. Because cIAP-1 and cIAP-2 also promote nuclear factor kappa B (NF-κB) activation by the canonical pathway, the effect of JP1584 on this signaling pathway was examined. Treatment with JP1584 inhibited TRAIL-induced NF-κB activation as well as TRAIL-mediated up-regulation of the NF-κB target gene, matrix metalloproteinase 7 (MMP7). JP1584 also reduced TRAIL-mediated CCA cell migration and invasion in vitro. Finally, in a syngeneic rat orthotopic CCA model, JP1584 administration reduced MMP7 messenger RNA levels and extrahepatic metastases. Conclusion Although the smac mimetic JP1584 does not sensitize cells to apoptosis, it reduces TRAIL-induced CCA cell metastatic behavior. These data support the emerging concept that IAPs are prometastatic and represent targets for antimetastatic therapies. PMID:20683954

  1. The effect of the thermal reduction temperature on the structure and sorption capacity of reduced graphene oxide materials

    NASA Astrophysics Data System (ADS)

    Dolbin, Alexandr V.; Khlistyuck, Maria V.; Esel'son, Valentin B.; Gavrilko, Viktor G.; Vinnikov, Nikolay A.; Basnukaeva, Razet M.; Maluenda, Irene; Maser, Wolfgang K.; Benito, Ana M.

    2016-01-01

    The influence of reduction temperatures on the structure and the sorption capacity of thermally reduced graphene (TRGO) has been investigated systematically. A set of TRGO materials were prepared by thermal treatment of parent graphene oxide (GO) at five temperatures (T = 200, 300, 500, 700, and 900 °C). Investigations of these materials by X-ray diffraction, Raman spectroscopy and X-ray photoemission spectroscopy methods have shown that both the structure and the residual oxygen functional groups on the TRGO surface can be controlled by varying the temperature of the thermal treatment. The data on the sorption and desorption of 4He, H2, N2, Ne and Kr gases in the temperature interval T = 2-290 K clearly demonstrate that the sorption capacity of TRGO is closely related to the structural changes induced by the treatment temperatures. It is important that the sorption capacities of TRGOs treated at 300 °C and at 900 °C significantly increase for all the gases used. The prominent increase in the sorption capacity at 300 °C is attributed to the structural disorder and liberation of the pores caused by the removal of intercalated water and labile oxygen functional groups (oFGs) favored at this temperature. At 900 °C the sorption capacity increases due to the generation of new defects on the TRGO surface, which provide additional access to the internal space between the folds and sheets of the TRGO structure. By tailoring the structural properties we emphasize the potential of TRGO as a highly efficient sorbent.

  2. Marginal Maternal Zinc Deficiency in Lactating Mice Reduces Secretory Capacity and Alters Milk Composition12

    PubMed Central

    Dempsey, Colleen; McCormick, Nicholas H.; Croxford, Thomas P.; Seo, Young Ah; Grider, Arthur; Kelleher, Shannon L.

    2012-01-01

    Dietary analysis predicts that marginal Zn deficiency is common in women of reproductive age. The lack of reliable biomarkers limits the capacity to assess Zn status and consequently understand effects of maternal Zn deficiency. We determined effects of marginal maternal Zn deficiency on mammary gland function, milk secretion, and milk composition in mice. Mice (n = 12/diet) were fed marginal (ZD; 15 mg Zn/kg diet) or adequate (ZA; 30 mg Zn/kg diet) Zn diets for 30 d prior to conception through mid-lactation. Mice fed the ZD had a higher plasma Zn concentration (~20%; P < 0.05) but lower milk Zn concentration (~15%; P < 0.05) compared with mice fed the ZA. ZnT2 abundance was higher (P < 0.05) in mice fed the ZD compared with mice fed the ZA; no effect on ZnT4 abundance was detected. The Zn concentration of mammary gland mitochondria tended to be ~40% greater in mice fed ZD (P = 0.07); this was associated with apoptosis and lower milk secretion (~80%; P < 0.01). Total milk protein was ~25% higher (P < 0.05), although the abundance of the major milk proteins (caseins and whey acidic protein) was lower (P < 0.05) in mice fed the ZD. Proteomic analysis of milk proteins revealed an increase (P < 0.05) in four proteins in mice fed the ZD. These findings illustrate that marginal maternal Zn deficiency compromises mammary gland function and milk secretion and alters milk composition. This suggests that lactating women who consume inadequate Zn may not produce and/or secrete an adequate amount of high quality milk to provide optimal nutrition to their developing infant. PMID:22357740

  3. 40 CFR 60.1560 - Can an affected municipal waste combustion unit reduce its capacity to less than 35 tons per day...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... combustion unit reduce its capacity to less than 35 tons per day rather than comply with my State plan? 60... Small Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Applicability of State Plans § 60.1560 Can an affected municipal waste combustion unit reduce its capacity to less than 35...

  4. 40 CFR 60.1560 - Can an affected municipal waste combustion unit reduce its capacity to less than 35 tons per day...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... combustion unit reduce its capacity to less than 35 tons per day rather than comply with my State plan? 60... Small Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Applicability of State Plans § 60.1560 Can an affected municipal waste combustion unit reduce its capacity to less than 35...

  5. Constitutive activation of myosin-dependent contractility sensitizes glioma tumor-initiating cells to mechanical inputs and reduces tissue invasion

    PubMed Central

    Wong, Sophie Y.; Ulrich, Theresa A.; Deleyrolle, Loic P.; MacKay, Joanna L.; Lin, Jung-Ming G.; Martuscello, Regina T.; Jundi, Musa A.; Reynolds, Brent A.; Kumar, Sanjay

    2015-01-01

    Tumor-initiating cells (TICs) perpetuate tumor growth, enable therapeutic resistance, and drive initiation of successive tumors. Virtually nothing is known about the role of mechanotransductive signaling in controlling TIC tumorigenesis, despite the recognized importance of altered mechanics in tissue dysplasia and the common observation that extracellular matrix (ECM) stiffness strongly regulates cell behavior. To address this open question, we cultured primary human glioblastoma (GBM) TICs on laminin-functionalized ECMs spanning a range of stiffnesses. Surprisingly, we found that these cells were largely insensitive to ECM stiffness cues, evading the inhibition of spreading, migration, and proliferation typically imposed by compliant ECMs. We hypothesize that this insensitivity may result from insufficient generation of myosin-dependent contractile force. Indeed, we found that both pharmacologic and genetic activation of cell contractility through RhoA GTPase, Rho-associated kinase (ROCK), or myosin light chain kinase (MLCK) restored stiffness-dependent spreading and motility, with TICs adopting the expected rounded and non-motile phenotype on soft ECMs. Moreover, constitutive activation of RhoA restricted three-dimensional invasion in both spheroid implantation and transwell paradigms. Orthotopic xenotransplantation studies revealed that control TICs formed tumors with classical GBM histopathology including diffuse infiltration and secondary foci, whereas TICs expressing a constitutively active mutant of RhoA produced circumscribed masses and yielded a 30% enhancement in mean survival time. This is the first direct evidence that manipulation of mechanotransductive signaling can alter the tumor-initiating capacity of GBM TICs, supporting further exploration of these signals as potential therapeutic targets and predictors of tumor initiating capacity within heterogeneous tumor cell populations. PMID:25634210

  6. The Electrogenic Bacterium Shewanella Oneidensis MR-1 and its Mutants with Increased Reducing Capacity

    NASA Astrophysics Data System (ADS)

    Voeikova, T. A.; Emelyanova, L. K.; Novikova, L. M.; Mordkovich, N. N.; Shakulov, R. S.; Debabov, V. G.

    2013-02-01

    Mutants of Shewanella oneidensis MR-1 resistant to fosfomycin, a toxic analogue of phosphoenolpyruvate, were obtained. The mutants exhibited an increased reducing activity and a higher rate of lactate utilization. A correlation was shown between the rates of metabolism of oxidized substrates and the rate of reduction of methylene blue, a mediator of electron transport. The mutants of S.oneidensis MR-1 will be used in microbial fuel cells (MFC) to enhance energy production from organic compounds. The strain S. oneidensis MR-1 and its mutants with an increased electron production will be used as a good source of bioelectricity in MFC in the experiments on the International Space Station.

  7. A novel high-throughput image based rapid Folin-Ciocalteau assay for assessment of reducing capacity in foods.

    PubMed

    Abderrahim, Mohamed; M Arribas, Silvia; Condezo-Hoyos, Luis

    2016-05-15

    The aim of the presented work was to develop and validate a novel high-throughput rapid Folin-Ciocalteau assay for the quantification of reducing capacity of foods based on image scanner (Image-F-C assay). The original rapid F-C assay using a 96-well plate was improved by adding a neutralization step that stabilizes the formed color, enabling image acquisition using a flatbed scanner. Although the scanner has been already used in other analytical applications, no analysis has been reported regarding the effect of the scanner model, the plate orientation or the reaction volume. In the present study, we establish that the mentioned parameters do affect the linearity and precision of image based Folin-Ciocalteau assay, and provide the optimal scanning conditions for the analyzed scanner models. Euclidean distance calculated from R (Red), G (Green) and B (Blue) values was chosen, based on linearity and sensitivity, in order to quantify the reducing capacity. An in-house program using free ImageJ macro language was written to calculate automatically the RGB values of each well. The Image-F-C assay is linear within the range of 0-20 mg L(-1) of gallic acid (R(2)≥0.9939). We compared reducing capacity values from real samples quantified by the image F-C assay and by a microplate reader and an inter-day relative standard error<8% was observed. Bland-Altman and correlation analyzes showed that there were no significant differences between the two methods. PMID:26992497

  8. Lack of LCAT reduces the LPS-neutralizing capacity of HDL and enhances LPS-induced inflammation in mice.

    PubMed

    Petropoulou, Peristera-Ioanna; Berbée, Jimmy F P; Theodoropoulos, Vassilios; Hatziri, Aikaterini; Stamou, Panagiota; Karavia, Eleni A; Spyridonidis, Alexandros; Karagiannides, Iordanes; Kypreos, Kyriakos E

    2015-10-01

    HDL has important immunomodulatory properties, including the attenuation of lipopolysaccharide (LPS)-induced inflammatory response. As lecithin-cholesterol acyltransferase (LCAT) is a critical enzyme in the maturation of HDL we investigated whether LCAT-deficient (Lcat(-/-)) mice present an increased LPS-induced inflammatory response. LPS (100μg/kg body weight)-induced cytokine response in Lcat(-/-) mice was markedly enhanced and prolonged compared to wild-type mice. Importantly, reintroducing LCAT expression using adenovirus-mediated gene transfer reverted their phenotype to that of wild-type mice. Ex vivo stimulation of whole blood with LPS (1-100ng/mL) showed a similar enhanced pro-inflammatory phenotype. Further characterization in RAW 264.7 macrophages in vitro showed that serum and HDL, but not chylomicrons, VLDL or the lipid-free protein fraction of Lcat(-/-) mice, had a reduced capacity to attenuate the LPS-induced TNFα response. Analysis of apolipoprotein composition revealed that LCAT-deficient HDL lacks significant amounts of ApoA-I and ApoA-II and is primarily composed of ApoE, while HDL from Apoa1(-/-) mice is highly enriched in ApoE and ApoA-II. ApoA-I-deficiency did not affect the capacity of HDL to neutralize LPS, though Apoa1(-/-) mice showed a pronounced LPS-induced cytokine response. Additional immunophenotyping showed that Lcat(-/-) , but not Apoa1(-/-) mice, have markedly increased circulating monocyte numbers as a result of increased Cd11b(+)Ly6C(med) monocytes, whereas 'pro-inflammatory' Cd11b(+)Ly6C(hi) monocytes were reduced. In line with this observation, peritoneal macrophages of Lcat(-/-) mice showed a markedly dampened LPS-induced TNFα response. We conclude that LCAT-deficiency increases LPS-induced inflammation in mice due to reduced LPS-neutralizing capacity of immature discoidal HDL and increased monocyte number. PMID:26170061

  9. Reduced clearance of triazolam in old age: relation to antipyrine oxidizing capacity.

    PubMed Central

    Greenblatt, D J; Divoll, M; Abernethy, D R; Moschitto, L J; Smith, R B; Shader, R I

    1983-01-01

    Thirty-three healthy male and female volunteers aged 21 to 87 years received a single 0.5 mg oral dose of triazolam. Plasma triazolam concentrations were measured in multiple samples drawn during 24 h after the dose. Mean triazolam elimination half-life was not significantly different between young and elderly men (3.0 vs 4.6 h), nor between young and elderly women (2.7 vs 3.2 h). However, apparent oral clearance of triazolam was significantly reduced in elderly as compared to young groups of both sexes, leading to higher peak plasma concentrations and increased total area under the curve. Values of half-life and clearance of antipyrine, a low-extraction hepatically oxidized compound, were poorly correlated with those of triazolam (r = 0.34 and 0.44, respectively), suggesting different mechanisms controlling age-related changes in clearance of these two hepatically oxidized drugs. PMID:6133545

  10. Extracellular vesicle–depleted fetal bovine and human sera have reduced capacity to support cell growth

    PubMed Central

    Eitan, Erez; Zhang, Shi; Witwer, Kenneth W.; Mattson, Mark P.

    2015-01-01

    Background Fetal bovine serum (FBS) is the most widely used serum supplement for mammalian cell culture. It supports cell growth by providing nutrients, growth signals, and protection from stress. Attempts to develop serum-free media that support cell expansion to the same extent as serum-supplemented media have not yet succeeded, suggesting that FBS contains one or more as-yet-undefined growth factors. One potential vehicle for the delivery of growth factors from serum to cultured cells is extracellular vesicles (EVs). Methods EV-depleted FBS and human serum were generated by 120,000g centrifugation, and its cell growth–supporting activity was measured. Isolated EVs from FBS were quantified and characterized by nanoparticle tracking analysis, electron microscopy, and protein assay. EV internalization into cells was quantified using fluorescent plate reader analysis and microscopy. Results Most cell types cultured with EV-depleted FBS showed a reduced growth rate but not an increased sensitivity to the DNA-damaging agent etoposide and the endoplasmic reticulum stress–inducing chemical tunicamycin. Supplying cells with isolated FBS-derived EVs enhanced their growth. FBS-derived EVs were internalized by mouse and human cells wherein 65±26% of them interacted with the lysosomes. EV-depleted human serum also exhibited reduced cell growth–promoting activity. Conclusions EVs play a role in the cell growth and survival-promoting effects of FBS and human serum. Thus, it is important to take the effect of EV depletion under consideration when planning EV extraction experiments and while attempting to develop serum-free media that support rapid cell expansion. In addition, these findings suggest roles for circulating EVs in supporting cell growth and survival in vivo. PMID:25819213

  11. Inhibition of ABCA1 protein degradation promotes HDL cholesterol efflux capacity and RCT and reduces atherosclerosis in mice.

    PubMed

    Huang, LinZhang; Fan, BaoYan; Ma, Ang; Shaul, Philip W; Zhu, HaiBo

    2015-05-01

    ABCA1 plays a key role in the initial lipidation of apoA-I, which generates circulating HDL cholesterol. Whereas it is known that the transcriptional upregulation of ABCA1 promotes HDL formation and reverse cholesterol transport (RCT), it is not known how the inhibition of ABCA1 protein degradation impacts HDL function. Employing the small molecule triacetyl-3-hydroxyphenyladenosine (IMM-H007), we determined how the attenuation of ABCA1 protein degradation affects HDL cholesterol efflux capacity, RCT, and atherosclerotic lesion formation. Pulse-chase analysis revealed that IMM-H007 inhibits ABCA1 degradation and facilitates its cell-surface localization in macrophages, and additional studies in macrophages showed that IMM-H007 thereby promotes cholesterol efflux. IMM-H007 treatment of Paigen diet-fed mice caused an increase in circulating HDL level, it increased the cholesterol efflux capacity of HDL, and it enhanced in vivo RCT from macrophages to the plasma, liver, and feces. Furthermore, ABCA1 degradation suppression by IMM-H007 reduced atherosclerotic plaque formation in apoE(-/-) mice. Thus, via effects on both ABCA1-expressing cells and circulating HDL function, the inhibition of ABCA1 protein degradation by IMM-H007 promotes HDL cholesterol efflux capacity and RCT and attenuates atherogenesis. IMM-H007 potentially represents a lead compound for the development of agents to augment HDL function. PMID:25761370

  12. Measurement of transformation temperatures and specific heat capacity of tungsten added reduced activation ferritic-martensitic steel

    NASA Astrophysics Data System (ADS)

    Raju, S.; Jeya Ganesh, B.; Rai, Arun Kumar; Mythili, R.; Saroja, S.; Mohandas, E.; Vijayalakshmi, M.; Rao, K. B. S.; Raj, Baldev

    2009-06-01

    The on-heating phase transformation temperatures up to the melting regime and the specific heat capacity of a reduced activation ferritic-martensitic steel (RAFM) with a nominal composition (wt%): 9Cr-0.09C-0.56Mn-0.23V-1W-0.063Ta-0.02N, have been measured using high temperature differential scanning calorimetry. The α -ferrite + carbides → γ-austenite transformation start and finish temperatures, namely A c1, and A c3, are found to be 1104 and 1144 K, respectively for a typical normalized and tempered microstructure. It is also observed that the martensite start ( MS) and finish ( Mf) temperatures are sensitive to the austenitising conditions. Typical MS and Mf values for the 1273 K normalized and 1033 K tempered samples are of the order 714 and 614 K, respectively. The heat capacity CP of the RAFM steel has been measured in the temperature range 473-1273 K, for different normalized and tempered samples. In essence, it is found that the CP of the fully martensitic microstructure is found to be lower than that of its tempered counterpart, and this difference begins to increase in an appreciable manner from about 800 K. The heat capacity of the normalized microstructure is found to vary from 480 to 500 J kg -1 K -1 at 500 K, where as that of the tempered steel is found to be higher by about, 150 J kg -1 K -1.

  13. Lanthanum Carbonate Reduces Urine Phosphorus Excretion: Evidence of High-Capacity Phosphate Binding

    PubMed Central

    Pennick, Michael; Poole, Lynne; Dennis, Kerry; Smyth, Michael

    2012-01-01

    The effectiveness of phosphate binders can be assessed by evaluating urinary phosphorus excretion in healthy volunteers, which indicates the ability of the phosphate binder to reduce gastrointestinal phosphate absorption. Healthy volunteers were enrolled into one of five separate randomized trials; four were open label and one double blind. Following a screening period of <28 days, participants received differing tablets containing lanthanum carbonate [LC, 3000 mg/day of elemental lanthanum (in one study other doses were also used)]. Participants received a standardized phosphate diet and remained in the relevant study center throughout the duration of each treatment period. The end point in all studies was the reduction in urinary phosphorus excretion. Reductions in mean 24-h urinary phosphorus excretion in volunteers receiving a lanthanum dose of 3000 mg/day were between 236 and 468 mg/day over the five separate studies. These data in healthy volunteers can be used to estimate the amount of reduction of dietary phosphate absorption by LC. The reduction in 24-h urinary phosphorus excretion per tablet was compared with published data on other phosphate binders. Although there are limitations, evidence suggests that LC is a very effective phosphate binder in terms of binding per tablet. PMID:22250993

  14. Diastolic function is associated with quality of life and exercise capacity in stable heart failure patients with reduced ejection fraction

    PubMed Central

    Bussoni, M.F.; Guirado, G.N.; Roscani, M.G.; Polegato, B.F.; Matsubara, L.S.; Bazan, S.G.Z.; Matsubara, B.B.

    2013-01-01

    Exercise capacity and quality of life (QOL) are important outcome predictors in patients with systolic heart failure (HF), independent of left ventricular (LV) ejection fraction (LVEF). LV diastolic function has been shown to be a better predictor of aerobic exercise capacity in patients with systolic dysfunction and a New York Heart Association (NYHA) classification ≥II. We hypothesized that the currently used index of diastolic function E/e' is associated with exercise capacity and QOL, even in optimally treated HF patients with reduced LVEF. This prospective study included 44 consecutive patients aged 55±11 years (27 men and 17 women), with LVEF<0.50 and NYHA functional class I-III, receiving optimal pharmacological treatment and in a stable clinical condition, as shown by the absence of dyspnea exacerbation for at least 3 months. All patients had conventional transthoracic echocardiography and answered the Minnesota Living with HF Questionnaire, followed by the 6-min walk test (6MWT). In a multivariable model with 6MWT as the dependent variable, age and E/e' explained 27% of the walked distance in 6MWT (P=0.002; multivariate regression analysis). No association was found between walk distance and LVEF or mitral annulus systolic velocity. Only normalized left atrium volume, a sensitive index of diastolic function, was associated with decreased QOL. Despite the small number of patients included, this study offers evidence that diastolic function is associated with physical capacity and QOL and should be considered along with ejection fraction in patients with compensated systolic HF. PMID:24036912

  15. Forest species diversity reduces disease risk in a generalist plant pathogen invasion

    USGS Publications Warehouse

    Haas, Sarah E.; Hooten, Mevin B.; Rizzo, David M.; Meentemeyer, Ross K.

    2011-01-01

    Empirical evidence suggests that biodiversity loss can increase disease transmission, yet our understanding of the 'diversity-disease hypothesis' for generalist pathogens in natural ecosystems is limited. We used a landscape epidemiological approach to examine two scenarios regarding diversity effects on the emerging plant pathogen Phytophthora ramorum across a broad, heterogeneous ecoregion: (1) an amplification effect exists where disease risk is greater in areas with higher plant diversity due to the pathogen's wide host range, or (2) a dilution effect where risk is reduced with increasing diversity due to lower competency of alternative hosts. We found evidence for pathogen dilution, whereby disease risk was lower in sites with higher species diversity, after accounting for potentially confounding effects of host density and landscape heterogeneity. Our results suggest that although nearly all plants in the ecosystem are hosts, alternative hosts may dilute disease transmission by competent hosts, thereby buffering forest health from infectious disease.

  16. Antioxidant capacity reduced in scallions grown under elevated CO 2 independent of assayed light intensity

    NASA Astrophysics Data System (ADS)

    Levine, Lanfang H.; Paré, Paul W.

    2009-10-01

    Long-duration manned space missions mandate the development of a sustainable life support system and effective countermeasures against damaging space radiation. To mitigate the risk of inevitable exposure to space radiation, cultivation of fresh fruits and vegetables rich in antioxidants is an attractive alternative to pharmacological agents. However it has yet to be established whether antioxidant properties of crops can be preserved or enhanced in a space environment where environmental conditions differ from that which plants have acclimated to on earth. Scallion ( Allium fistulosum) rich in antioxidant vitamins C and A, and flavonoids was used as a model plant to study the impact of a range of CO 2 concentrations and light intensities that are likely encountered in a space habitat on food quality traits. Scallions were hydroponically grown in controlled environmental chambers under a combination of 3 CO 2 concentrations of 400, 1200 and 4000 μmol mol -1 and 3 light intensity levels of 150, 300, 450 μmol m -2 s -1. Total antioxidant activity (TAA) of scallion extracts was determined using a radical cation scavenging assay. Both elevated CO 2 and increasing light intensity enhanced biomass accumulation, but effects on TAA (based on dry weight) differed. TAA was reduced for plants grown under elevated CO 2, but remained unchanged with increases in light intensity. Elevated CO 2 stimulated greater biomass production than antioxidants, while an increase in photosynthetic photo flux promoted the synthesis of antioxidant compounds at a rate similar to that of biomass. Consequently light is a more effective stimulus than CO 2 for antioxidant production.

  17. The Capacity of Red Blood Cells to Reduce Nitrite Determines Nitric Oxide Generation under Hypoxic Conditions

    PubMed Central

    Fens, Marcel H.; Larkin, Sandra K.; Oronsky, Bryan; Scicinski, Jan; Morris, Claudia R.; Kuypers, Frans A.

    2014-01-01

    Nitric oxide (NO) is a key regulator of vascular tone. Endothelial nitric oxide synthase (eNOS) is responsible for NO generation under normoxic conditions. Under hypoxia however, eNOS is inactive and red blood cells (RBC) provide an alternative NO generation pathway from nitrite to regulate hypoxic vasodilation. While nitrite reductase activity of hemoglobin is well acknowledged, little is known about generation of NO by intact RBC with physiological hemoglobin concentrations. We aimed to develop and apply a new approach to provide insights in the ability of RBC to convert nitrite into NO under hypoxic conditions. We established a novel experimental setup to evaluate nitrite uptake and the release of NO from RBC into the gas-phase under different conditions. NO measurements were similar to well-established clinical measurements of exhaled NO. Nitrite uptake was rapid, and after an initial lag phase NO release from RBC was constant in time under hypoxic conditions. The presence of oxygen greatly reduced NO release, whereas inhibition of eNOS and xanthine oxidoreductase (XOR) did not affect NO release. A decreased pH increased NO release under hypoxic conditions. Hypothermia lowered NO release, while hyperthermia increased NO release. Whereas fetal hemoglobin did not alter NO release compared to adult hemoglobin, sickle RBC showed an increased ability to release NO. Under all conditions nitrite uptake by RBC was similar. This study shows that nitrite uptake into RBC is rapid and release of NO into the gas-phase continues for prolonged periods of time under hypoxic conditions. Changes in the RBC environment such as pH, temperature or hemoglobin type, affect NO release. PMID:25007272

  18. Biodegradable interstitial release polymer loading a novel small molecule targeting Axl receptor tyrosine kinase and reducing brain tumour migration and invasion

    PubMed Central

    Yen, S-Y; Chen, S-R; Hsieh, J; Li, Y-S; Chuang, S-E; Chuang, H-M; Huang, M-H; Lin, S-Z; Harn, H-J; Chiou, T-W

    2016-01-01

    Glioblastoma multiforme (GBM) is the most common and aggressive brain tumour. The neoplasms are difficult to resect entirely because of their highly infiltration property and leading to the tumour edge is unclear. Gliadel wafer has been used as an intracerebral drug delivery system to eliminate the residual tumour. However, because of its local low concentration and short diffusion distance, patient survival improves non-significantly. Axl is an essential regulator in cancer metastasis and patient survival. In this study, we developed a controlled-release polyanhydride polymer loading a novel small molecule, n-butylidenephthalide (BP), which is not only increasing local drug concentration and extending its diffusion distance but also reducing tumour invasion, mediated by reducing Axl expression. First, we determined that BP inhibited the expression of Axl in a dose- and time-dependent manner and reduced the migratory and invasive capabilities of GBM cells. In addition, BP downregulated matrix metalloproteinase activity, which is involved in cancer cell invasion. Furthermore, we demonstrated that BP regulated Axl via the extracellular signal-regulated kinases pathway. Epithelial-to-mesenchymal transition (EMT) is related to epithelial cells in the invasive migratory mesenchymal cells that underlie cancer progression; we demonstrated that BP reduced the expression of EMT-related genes. Furthermore, we used the overexpression of Axl in GBM cells to prove that Axl is a crucial target in the inhibition of GBM EMT, migration and invasion. In an in vivo study, we demonstrated that BP inhibited tumour growth and suppressed Axl expression in a dose-dependent manner according to a subcutaneous tumour model. Most importantly, in an intracranial tumour model with BP wafer in situ treatment, we demonstrated that the BP wafer not only significantly increased the survival rate but also decreased Axl expression, and inhibited tumour invasion. These results contribute to the

  19. French invasive Asian tiger mosquito populations harbor reduced bacterial microbiota and genetic diversity compared to Vietnamese autochthonous relatives

    PubMed Central

    Minard, G.; Tran, F. H.; Van, Van Tran; Goubert, C.; Bellet, C.; Lambert, G.; Kim, Khanh Ly Huynh; Thuy, Trang Huynh Thi; Mavingui, P.; Valiente Moro, C.

    2015-01-01

    The Asian tiger mosquito Aedes albopictus is one of the most significant pathogen vectors of the twenty-first century. Originating from Asia, it has invaded a wide range of eco-climatic regions worldwide. The insect-associated microbiota is now recognized to play a significant role in host biology. While genetic diversity bottlenecks are known to result from biological invasions, the resulting shifts in host-associated microbiota diversity has not been thoroughly investigated. To address this subject, we compared four autochthonous Ae. albopictus populations in Vietnam, the native area of Ae. albopictus, and three populations recently introduced to Metropolitan France, with the aim of documenting whether these populations display differences in host genotype and bacterial microbiota. Population-level genetic diversity (microsatellite markers and COI haplotype) and bacterial diversity (16S rDNA metabarcoding) were compared between field-caught mosquitoes. Bacterial microbiota from the whole insect bodies were largely dominated by Wolbachia pipientis. Targeted analysis of the gut microbiota revealed a greater bacterial diversity in which a fraction was common between French and Vietnamese populations. The genus Dysgonomonas was the most prevalent and abundant across all studied populations. Overall genetic diversities of both hosts and bacterial microbiota were significantly reduced in recently established populations of France compared to the autochthonous populations of Vietnam. These results open up many important avenues of investigation in order to link the process of geographical invasion to shifts in commensal and symbiotic microbiome communities, as such shifts may have dramatic impacts on the biology and/or vector competence of invading hematophagous insects. PMID:26441903

  20. Reduced expression of fumarate hydratase in clear cell renal cancer mediates HIF-2α accumulation and promotes migration and invasion.

    PubMed

    Sudarshan, Sunil; Shanmugasundaram, Karthigayan; Naylor, Susan L; Lin, Shu; Livi, Carolina B; O'Neill, Christine F; Parekh, Dipen J; Yeh, I-Tien; Sun, Lu-Zhe; Block, Karen

    2011-01-01

    Germline mutations of FH, the gene that encodes for the tricarboxylic acid TCA (TCA) cycle enzyme fumarate hydratase, are associated with an inherited form of cancer referred to as Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC). Individuals with HLRCC are predisposed to the development of highly malignant and lethal renal cell carcinoma (RCC). The mechanisms of tumorigenesis proposed have largely focused on the biochemical consequences of loss of FH enzymatic activity. While loss of the tumor suppressor gene von Hippel Lindau (VHL) is thought to be an initiating event for the majority of RCCs, a role for FH in sporadic renal cancer has not been explored. Here we report that FH mRNA and protein expression are reduced in clear cell renal cancer, the most common histologic variant of kidney cancer. Moreover, we demonstrate that reduced FH leads to the accumulation of hypoxia inducible factor- 2α (HIF-2α), a transcription factor known to promote renal carcinogenesis. Finally, we demonstrate that overexpression of FH in renal cancer cells inhibits cellular migration and invasion. These data provide novel insights into the tumor suppressor functions of FH in sporadic kidney cancer. PMID:21695080

  1. Hispolon inhibits TPA-induced invasion by reducing MMP-9 expression through the NF-κB signaling pathway in MDA-MB-231 human breast cancer cells

    PubMed Central

    SUN, YI-SHENG; ZHAO, ZHAO; ZHU, HAN-PING

    2015-01-01

    Hispolon has been demonstrated to possess analgesic, anti-inflammatory and anticancer activities. However, whether hispolon prevents the invasion of breast carcinoma cells and the underlying mechanisms of its action remain unknown. In the present study, various assays, including a matrigel-based Transwell invasion assay and electrophoretic mobility shift assay, were used to investigate the anti-invasion effect of hispolon and explore its mechanism of action. The results revealed that hispolon inhibited the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced migration and invasion of MDA-MB-231 human breast cancer cells at non-toxic concentrations. Hispolon also prevented the TPA-induced secretion of matrix metalloproteinase-9 (MMP-9) and reduced its expression at the transcriptional and translational levels. Furthermore, the phosphorylation of IκBα was reduced by hispolon, which resulted in the suppression of nuclear factor-κB (NF-κB), and p65 phosphorylation and nuclear translocation. An electrophoretic mobility shift assay demonstrated that NF-κB DNA-binding activity was induced by TPA and inhibited by hispolon. In addition, Bay 11–7082, which is a specific inhibitor of NF-κB, functioned in a similar manner as hispolon and blocked the secretion and expression of MMP-9. In conclusion, the results of the present study indicated that hispolon inhibited TPA-induced migration and invasion of MDA-MB-231 cells by reducing the secretion and expression of MMP-9 through the NF-κB signaling pathway. PMID:26171065

  2. Efficacy of plastic mesh tubes in reducing herbivory damage by the invasive nutria (Myocastor coypus) in an urban restoration site

    USGS Publications Warehouse

    Sheffels, Trevor R.; Systma, Mark D.; Carter, Jacoby; Taylor, Jimmy D.

    2014-01-01

    The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria(Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar® plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar® tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood (Populus balsamifera ssp trichocarpa) over red osier dogwood (Cornussericea) and willow (Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar® plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes.

  3. Regulatory T cells with reduced repressor capacities are extensively amplified in pulmonary sarcoid lesions and sustain granuloma formation.

    PubMed

    Rappl, Gunter; Pabst, Stefan; Riemann, Dagmar; Schmidt, Annette; Wickenhauser, Claudia; Schütte, Wolfgang; Hombach, Andreas A; Seliger, Barbara; Grohé, Christian; Abken, Hinrich

    2011-07-01

    Sarcoidosis can evolve into a chronic disease with persistent granulomas accompanied by progressive fibrosis. While an unlimited inflammatory response suggests an impaired immune control in sarcoid lesions, it stands in contrast to the massive infiltration with CD4(+)CD25(high)FoxP3(+) regulatory T cells. We here revealed that those Treg cells in affected lung lesions were mainly derived from activated natural Treg cells with GARP (LRRC32)-positive phenotype but exhibited reduced repressor capacities despite high IL-10 and TGF-beta 1 levels. The repressive capacity of blood Treg cells, in contrast, was not impaired compared to age-matched healthy donors. Treg derived cells in granuloma lesions have undergone extensive rounds of amplifications indicated by shortened telomeres compared to blood Treg cells of the same patient. Lesional Treg derived cells moreover secreted pro-inflammatory cytokines including IL-4 which sustains granuloma formation through fibroblast amplification and the activation of mast cells, the latter indicated by the expression of membrane-bound oncostatin M. PMID:21482483

  4. Reducing the power consumption in LTE-Advanced wireless access networks by a capacity based deployment tool

    NASA Astrophysics Data System (ADS)

    Deruyck, Margot; Joseph, Wout; Tanghe, Emmeric; Martens, Luc

    2014-09-01

    As both the bit rate required by applications on mobile devices and the number of those mobile devices are steadily growing, wireless access networks need to be expanded. As wireless networks also consume a lot of energy, it is important to develop energy-efficient wireless access networks in the near future. In this study, a capacity-based deployment tool for the design of energy-efficient wireless access networks is proposed. Capacity-based means that the network responds to the instantaneous bit rate requirements of the users active in the selected area. To the best of our knowledge, such a deployment tool for energy-efficient wireless access networks has never been presented before. This deployment tool is applied to a realistic case in Ghent, Belgium, to investigate three main functionalities incorporated in LTE-Advanced: carrier aggregation, heterogeneous deployments, and Multiple-Input Multiple-Output (MIMO). The results show that it is recommended to introduce femtocell base stations, supporting both MIMO and carrier aggregation, into the network (heterogeneous deployment) to reduce the network's power consumption. For the selected area and the assumptions made, this results in a power consumption reduction up to 70%. Introducing femtocell base stations without MIMO and carrier aggregation can already result in a significant power consumption reduction of 38%.

  5. Aberrant Salience Is Related to Reduced Reinforcement Learning Signals and Elevated Dopamine Synthesis Capacity in Healthy Adults.

    PubMed

    Boehme, Rebecca; Deserno, Lorenz; Gleich, Tobias; Katthagen, Teresa; Pankow, Anne; Behr, Joachim; Buchert, Ralph; Roiser, Jonathan P; Heinz, Andreas; Schlagenhauf, Florian

    2015-07-15

    The striatum is known to play a key role in reinforcement learning, specifically in the encoding of teaching signals such as reward prediction errors (RPEs). It has been proposed that aberrant salience attribution is associated with impaired coding of RPE and heightened dopamine turnover in the striatum, and might be linked to the development of psychotic symptoms. However, the relationship of aberrant salience attribution, RPE coding, and dopamine synthesis capacity has not been directly investigated. Here we assessed the association between a behavioral measure of aberrant salience attribution, the salience attribution test, to neural correlates of RPEs measured via functional magnetic resonance imaging while healthy participants (n = 58) performed an instrumental learning task. A subset of participants (n = 27) also underwent positron emission tomography with the radiotracer [(18)F]fluoro-l-DOPA to quantify striatal presynaptic dopamine synthesis capacity. Individual variability in aberrant salience measures related negatively to ventral striatal and prefrontal RPE signals and in an exploratory analysis was found to be positively associated with ventral striatal presynaptic dopamine levels. These data provide the first evidence for a specific link between the constructs of aberrant salience attribution, reduced RPE processing, and potentially increased presynaptic dopamine function. PMID:26180188

  6. Plasma cholesterol efflux capacity from human THP-1 macrophages is reduced in HIV-infected patients: impact of HAART[S

    PubMed Central

    El Khoury, Petra; Ghislain, Mathilde; Villard, Elise F.; Le Goff, Wilfried; Lascoux-Combe, Caroline; Yeni, Patrick; Meyer, Laurence; Vigouroux, Corinne; Goujard, Cécile; Guerin, Maryse

    2015-01-01

    The capacity of HDL to remove cholesterol from macrophages is inversely associated with the severity of angiographic coronary artery disease. The effect of human immunodeficiency virus (HIV) infection or its treatment on the ability of HDL particles to stimulate cholesterol efflux from human macrophages has never been studied. We evaluated the capacity of whole plasma and isolated HDL particles from HIV-infected subjects (n = 231) and uninfected controls (n = 200), as well as in a subset of 41 HIV subjects receiving highly active antiretroviral therapy (HAART) to mediate cholesterol efflux from human macrophages. Plasma cholesterol efflux capacity was reduced (−12%; P = 0.001) in HIV patients as compared with controls. HIV infection reduced by 27% (P < 0.05) the capacity of HDL subfractions to promote cholesterol efflux from macrophages. We observed a reduced ABCA1-dependent efflux capacity of plasma (−27%; P < 0.0001) from HIV-infected subjects as a result of a reduction in the efflux capacity of HDL3 particles. HAART administration restored the capacity of plasma from HIV patients to stimulate cholesterol efflux from human macrophages (9.4%; P = 0.04). During HIV infection, the capacity of whole plasma to remove cholesterol from macrophages is reduced, thus potentially contributing to the increased coronary heart disease in the HIV population. HAART administration restored the removal of cholesterol from macrophages by increasing HDL functionality. PMID:25573889

  7. Reduced mental capacity and behavior of a rider of a bicycle simulator under alcohol stress or under dual task load

    NASA Technical Reports Server (NTRS)

    Soede, M.

    1977-01-01

    Experiments were carried out on a bicycle simulator with alcohol administration and a binary choice task in separate sessions, intending to reduce the subject's mental capacity. Before and after such sessions a visual evoked response measurement was done. The subject's performance was analyzed with describing function techniques. The results indicate that the alcohol affects the course-following task as well as the balancing task. The binary choice task is more specifically influencing the course-following task. The dual task shows a more pronounced effect on the recovery of the evoked response. The alcohol is delaying the recovery curve of the evoked response. A tentative explanation can be given which agrees with the performance data.

  8. MiR-15b and miR-152 reduce glioma cell invasion and angiogenesis via NRP-2 and MMP-3

    PubMed Central

    Zheng, Xuguang; Chopp, Michael; Lu, Yong; Buller, Ben; Jiang, Feng

    2013-01-01

    Invasion and angiogenesis are two major pathophysiological features of malignant gliomas. Anti-angiogenic treatment lead to enhanced tumor cell invasion and metastasis. In the current study, we tested invasion and angiogenesis related mRNA expression profiles of glioma cells via RT2Profiler PCR Array by employing an in vivo 9L homograft glioma tumor animal model and an in vitro hypoxic cell culture model. The miRNA profile was also obtained via miRNA array. Genes with mRNA expression that changed significantly in the mRNA array were selected to predict possible miRNAs that regulate mRNA expression using the TargetScan database, and were then matched with miRNA array results. Based on these criteria, NRP-2 with the matching miRNA miR-15b, and MMP-3 with the matching miRNA miR-152 were selected for further study, and to determine whether they regulate tumor microenviroment changes and affect glioma angiogenesis and invasion. The protein expression of NRP-2 and MMP-3 were verified in 9L glioma cells and were negatively correlated to miR-15b and miR-152 level, respectively. Rat astrocytes (primary and cell line), when co-cultured with 9L glioma cells, showed significantly elevated NRP-2, MMP-3 expression and reduced miR-15b, miR-152 expression compared to non co-cultured astrocytes. Luciferase activity assay confirmed that miR-15b and miR-152 attenuate expression of NRP-2 and MMP-3 protein by binding to NRP-2 and MMP-3 transcript, respectively. In vitro invasion assay data showed that miR-15b and miR-152 significantly decreased 9L cell invasiveness. Anti-miR-15b and anti-miR-152 inhibitors counteracted the inhibition of invasion caused by miR-15b and miR-152. In vitro tube formation assay data showed that miR-15b, but not miR-152, reduced tube formation in cultured endothelial cells, and anti-miR-15b inhibitor counteracted the inhibition of tube formation caused by miR-15b. A preliminary pathway study indicated that miR-15b and miR-152 deactivated the MEK-ERK pathway

  9. Assessment of the capacity of vehicle cabin air inlet filters to reduce diesel exhaust-induced symptoms in human volunteers

    PubMed Central

    2014-01-01

    Background Exposure to particulate matter (PM) air pollution especially derived from traffic is associated with increases in cardiorespiratory morbidity and mortality. In this study, we evaluated the ability of novel vehicle cabin air inlet filters to reduce diesel exhaust (DE)-induced symptoms and markers of inflammation in human subjects. Methods Thirty healthy subjects participated in a randomized double-blind controlled crossover study where they were exposed to filtered air, unfiltered DE and DE filtered through two selected particle filters, one with and one without active charcoal. Exposures lasted for one hour. Symptoms were assessed before and during exposures and lung function was measured before and after each exposure, with inflammation assessed in peripheral blood five hours after exposures. In parallel, PM were collected from unfiltered and filtered DE and assessed for their capacity to drive damaging oxidation reactions in a cell-free model, or promote inflammation in A549 cells. Results The standard particle filter employed in this study reduced PM10 mass concentrations within the exposure chamber by 46%, further reduced to 74% by the inclusion of an active charcoal component. In addition use of the active charcoal filter was associated by a 75% and 50% reduction in NO2 and hydrocarbon concentrations, respectively. As expected, subjects reported more subjective symptoms after exposure to unfiltered DE compared to filtered air, which was significantly reduced by the filter with an active charcoal component. There were no significant changes in lung function after exposures. Similarly diesel exhaust did not elicit significant increases in any of the inflammatory markers examined in the peripheral blood samples 5 hour post-exposure. Whilst the filters reduced chamber particle concentrations, the oxidative activity of the particles themselves, did not change following filtration with either filter. In contrast, diesel exhaust PM passed through the

  10. The Probiotic Escherichia coli Nissle 1917 Reduces Pathogen Invasion and Modulates Cytokine Expression in Caco-2 Cells Infected with Crohn's Disease-Associated E. coli LF82 ▿

    PubMed Central

    Huebner, Claudia; Ding, Yaoyao; Petermann, Ivonne; Knapp, Christoph; Ferguson, Lynnette R.

    2011-01-01

    Increased numbers of adherent invasive Escherichia coli (AIEC) have been found in Crohn's disease (CD) patients. In this report, we investigate the potential of the probiotic Escherichia coli Nissle 1917 (EcN) to reduce features associated with AIEC pathogenicity in an already established infection with AIEC reference strain LF82. PMID:21317252

  11. Reduced pancreatic protein secretion in response to cholecystokinin (CCK) in the obese Zucker rat correlates with a reduced receptor capacity for CCK

    SciTech Connect

    Praissman, M.; Izzo, R.S.

    1986-08-01

    Pancreatic membrane receptors for cholecystokinin (CCK) in obese and nonobese Zucker rats were compared with the use of a biologically active (/sup 125/I)iodo-CCK-8 radioprobe. Membrane homogenates from obese rats bound half the amount of radioligand in 2 h as did membranes from lean rats (specifically bound, 7.0% vs. 14.0%; P less than 0.001). The reduced binding in membranes from obese rats did not result from kinetic effects or radioligand degradation; similar rates of association and dissociation of (/sup 125/I)iodo-CCK-8 were obtained in membrane preparations from both, and no differences were found in the extent of radioligand degradation in the two membrane preparations. These differences also did not reflect an effect of cell size, as pancreatic acinar cells from obese and nonobese rats had about the same perimeters (24.6 and 26.3 micron, respectively) and areas (30.1 and 34.2 micron 2, respectively). Scatchard-type plots of competitive displacement data for CCK-binding sites on pancreatic membranes from both genotypes were curvilinear and were analyzed by a two-site binding model. The Kd values for both the high (0.56 vs. 0.45 nM) and low (9.0 vs. 14 nM) affinity sites on membranes from nonobese and obese rats, respectively, were the same (P greater than 0.1), whereas the capacities for CCK in the high (365 vs. 165 fmol/mg protein) and low (1020 vs. 360 fmol/mg protein) affinity regions were significantly different (P less than 0.025). This difference in CCK receptor capacity was reflected by a reduced pancreatic protein secretory response in the obese rat. After injections of 40, 80, 160, and 320 ng CCK/kg BW, total pancreatic protein secretion in nonobese rats increased 5, 12, 19, and 21 times above basal levels, whereas the same doses caused 2-, 6-, 12-, and 13-fold increases in obese rats.

  12. Poultry Body Temperature Contributes to Invasion Control through Reduced Expression of Salmonella Pathogenicity Island 1 Genes in Salmonella enterica Serovars Typhimurium and Enteritidis

    PubMed Central

    Petri, Nicholas; Daron, Caitlyn; Pereira, Rafaela; Mendoza, Mary; Hassan, Hosni M.; Koci, Matthew D.

    2015-01-01

    Salmonella enterica serovars Typhimurium (S. Typhimurium) and Enteritidis (S. Enteritidis) are foodborne pathogens, and outbreaks are often associated with poultry products. Chickens are typically asymptomatic when colonized by these serovars; however, the factors contributing to this observation are uncharacterized. Whereas symptomatic mammals have a body temperature between 37°C and 39°C, chickens have a body temperature of 41°C to 42°C. Here, in vivo experiments using chicks demonstrated that numbers of viable S. Typhimurium or S. Enteritidis bacteria within the liver and spleen organ sites were ≥4 orders of magnitude lower than those within the ceca. When similar doses of S. Typhimurium or S. Enteritidis were given to C3H/HeN mice, the ratio of the intestinal concentration to the liver/spleen concentration was 1:1. In the avian host, this suggested poor survival within these tissues or a reduced capacity to traverse the host epithelial layer and reach liver/spleen sites or both. Salmonella pathogenicity island 1 (SPI-1) promotes localization to liver/spleen tissues through invasion of the epithelial cell layer. Following in vitro growth at 42°C, SPI-1 genes sipC, invF, and hilA and the SPI-1 rtsA activator were downregulated compared to expression at 37°C. Overexpression of the hilA activators fur, fliZ, and hilD was capable of inducing hilA-lacZ at 37°C but not at 42°C despite the presence of similar levels of protein at the two temperatures. In contrast, overexpression of either hilC or rtsA was capable of inducing hilA and sipC at 42°C. These data indicate that physiological parameters of the poultry host, such as body temperature, have a role in modulating expression of virulence. PMID:26386070

  13. Fn14 receptor promotes invasive potential and metastatic capacity of non-small lung adenocarcinoma cells through the up-regulation of integrin α6

    PubMed Central

    Jandova, J.; Mason, C. J.; Pawar, S. C.; Watts, G. S.

    2015-01-01

    Lung cancer is one of the leading causes of cancer-related death around the world with the majority of diagnoses being non-small cell lung cancer (NSCLC). Given the poor survival rate and efficacy of current therapy for NSCLC, there is a need to identify and develop new therapeutic targets for treatment. We have observed significantly up-regulated levels of Fn14 in clinical samples of lung cancer relative to normal adjacent tissue. However, the functional role of Fn14 in these tumors is not understood yet. We used RT-PCR to establish the Fn14 expression profile in various NSCLC cell lines. Using isogenic variants of H460 NSCLC cell line with low, intermediate and high Fn14 expression as a cellular model, we determined that increased levels of integrin α6 in cells over-expressing Fn14 is suggestive of an important role of α6β1-fn14 interactions in motility of lung carcinoma and formation of metastases. Enhanced levels of Fn14 correlated with higher tumor cell migration and invasion in an MMP-1 dependent manner. Cells over-expressing Fn14 showed increased in vivo tumor formation with metastatic capacity to lymph nodes, lungs and liver. Thus, this research may be a step toward developing improved treatment strategies for NSCLC by improved detection and inhibition of metastases. PMID:25563366

  14. Growth Retardation, Reduced Invasiveness, and Impaired Colistin-Mediated Cell Death Associated with Colistin Resistance Development in Acinetobacter baumannii

    PubMed Central

    Poulou, Aggeliki; Dafopoulou, Konstantina; Chabane, Yassine Nait; Kristo, Ioulia; Makris, Demosthenes; Hardouin, Julie; Cosette, Pascal; Tsakris, Athanassios; Dé, Emmanuelle

    2014-01-01

    Two colistin-susceptible/colistin-resistant (Cols/Colr) pairs of Acinetobacter baumannii strains assigned to international clone 2, which is prevalent worldwide, were sequentially recovered from two patients after prolonged colistin administration. Compared with the respective Cols isolates (Ab248 and Ab299, both having a colistin MIC of 0.5 μg/ml), both Colr isolates (Ab249 and Ab347, with colistin MICs of 128 and 32 μg/ml, respectively) significantly overexpressed pmrCAB genes, had single-amino-acid shifts in the PmrB protein, and exhibited significantly slower growth. The Colr isolate Ab347, tested by proteomic analysis in comparison with its Cols counterpart Ab299, underexpressed the proteins CsuA/B and C from the csu operon (which is necessary for biofilm formation). This isolate also underexpressed aconitase B and different enzymes involved in the oxidative stress response (KatE catalase, superoxide dismutase, and alkyl hydroperoxide reductase), suggesting a reduced response to reactive oxygen species (ROS) and, consequently, impaired colistin-mediated cell death through hydroxyl radical production. Cols isolates that were indistinguishable by macrorestriction analysis from Ab299 caused six sequential bloodstream infections, and isolates indistinguishable from Ab248 caused severe soft tissue infection, while Colr isolates indistinguishable from Ab347 and Ab249 were mainly colonizers. In particular, a Cols isolate identical to Ab299 was still invading the bloodstream 90 days after the colonization of this patient by Colr isolates. These observations indicate considerably lower invasiveness of A. baumannii clinical isolates following the development of colistin resistance. PMID:24247145

  15. Growth retardation, reduced invasiveness, and impaired colistin-mediated cell death associated with colistin resistance development in Acinetobacter baumannii.

    PubMed

    Pournaras, Spyros; Poulou, Aggeliki; Dafopoulou, Konstantina; Chabane, Yassine Nait; Kristo, Ioulia; Makris, Demosthenes; Hardouin, Julie; Cosette, Pascal; Tsakris, Athanassios; Dé, Emmanuelle

    2014-01-01

    Two colistin-susceptible/colistin-resistant (Col(s)/Col(r)) pairs of Acinetobacter baumannii strains assigned to international clone 2, which is prevalent worldwide, were sequentially recovered from two patients after prolonged colistin administration. Compared with the respective Col(s) isolates (Ab248 and Ab299, both having a colistin MIC of 0.5 μg/ml), both Col(r) isolates (Ab249 and Ab347, with colistin MICs of 128 and 32 μg/ml, respectively) significantly overexpressed pmrCAB genes, had single-amino-acid shifts in the PmrB protein, and exhibited significantly slower growth. The Col(r) isolate Ab347, tested by proteomic analysis in comparison with its Col(s) counterpart Ab299, underexpressed the proteins CsuA/B and C from the csu operon (which is necessary for biofilm formation). This isolate also underexpressed aconitase B and different enzymes involved in the oxidative stress response (KatE catalase, superoxide dismutase, and alkyl hydroperoxide reductase), suggesting a reduced response to reactive oxygen species (ROS) and, consequently, impaired colistin-mediated cell death through hydroxyl radical production. Col(s) isolates that were indistinguishable by macrorestriction analysis from Ab299 caused six sequential bloodstream infections, and isolates indistinguishable from Ab248 caused severe soft tissue infection, while Col(r) isolates indistinguishable from Ab347 and Ab249 were mainly colonizers. In particular, a Col(s) isolate identical to Ab299 was still invading the bloodstream 90 days after the colonization of this patient by Col(r) isolates. These observations indicate considerably lower invasiveness of A. baumannii clinical isolates following the development of colistin resistance. PMID:24247145

  16. Nanostructured zirconia decorated reduced graphene oxide based efficient biosensing platform for non-invasive oral cancer detection.

    PubMed

    Kumar, Suveen; Sharma, Jai Gopal; Maji, Sagar; Malhotra, Bansi Dhar

    2016-04-15

    We report results of the studies relating to fabrication of a non-invasive, label-free and an efficient biosensing platform for detection of the oral cancer biomarker (CYFRA-21-1). One step hydrothermal process was used for uniform decoration of nanostructured zirconia (average particle size 13 nm) on reduced graphene oxide (ZrO2-RGO) to avoid coagulation of the zirconia nanoparticles and to obtain enhanced electrochemical performance of ZrO2-RGO nanocomposite based biosensor. Further, ZrO2-RGO has been functionalized using 3-aminopropyl triethoxy saline (APTES) and electrophoretically deposited on the indium tin oxide coated glass substrate at a low DC potential.The APTES/ZrO2-RGO/ITO electrode exhibits improved heterogeneous electron transfer (more than two times) with respect to that of the APTES/ZrO2/ITO electrode indicating faster electron transfer kinetics. The -NH2 containing APTES/ZrO2-RGO/ITO platform is further biofunctionalized with anti-CYFRA-21-1. The structural and morphological investigations of the ZrO2-RGO based biosensing platform have been accomplished using X-ray diffraction (XRD), electrochemical, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR) studies. This immunosensor exhibits a wider linear detection range (2-22 ng mL(-1)), excellent sensitivity (0.756 µA mL ng(-1)) and a remarkable lower detection limit of 0.122 ng mL(-1). The observed results have been validated via enzyme linked immunosorbent assay (ELISA). PMID:26657594

  17. High fatty acid oxidation capacity and phosphorylation control despite elevated leak and reduced respiratory capacity in northern elephant seal muscle mitochondria.

    PubMed

    Chicco, Adam J; Le, Catherine H; Schlater, Amber; Nguyen, Alex; Kaye, Spencer; Beals, Joseph W; Scalzo, Rebecca L; Bell, Christopher; Gnaiger, Erich; Costa, Daniel P; Crocker, Daniel E; Kanatous, Shane B

    2014-08-15

    Northern elephant seals (Mirounga angustirostris) are extreme, hypoxia-adapted endotherms that rely largely on aerobic metabolism during extended breath-hold dives in near-freezing water temperatures. While many aspects of their physiology have been characterized to account for these remarkable feats, the contribution of adaptations in the aerobic powerhouses of muscle cells, the mitochondria, are unknown. In the present study, the ontogeny and comparative physiology of elephant seal muscle mitochondrial respiratory function was investigated under a variety of substrate conditions and respiratory states. Intact mitochondrial networks were studied by high-resolution respirometry in saponin-permeabilized fiber bundles obtained from primary swimming muscles of pup, juvenile and adult seals, and compared with fibers from adult human vastus lateralis. Results indicate that seal muscle maintains a high capacity for fatty acid oxidation despite a progressive decrease in total respiratory capacity as animals mature from pups to adults. This is explained by a progressive increase in phosphorylation control and fatty acid utilization over pyruvate in adult seals compared with humans and seal pups. Interestingly, despite higher indices of oxidative phosphorylation efficiency, juvenile and adult seals also exhibit a ~50% greater capacity for respiratory 'leak' compared with humans and seal pups. The ontogeny of this phenotype suggests it is an adaptation of muscle to the prolonged breath-hold exercise and highly variable ambient temperatures experienced by mature elephant seals. These studies highlight the remarkable plasticity of mammalian mitochondria to meet the demands for both efficient ATP production and endothermy in a cold, oxygen-limited environment. PMID:24902742

  18. Gene deletion of P2Y4 receptor lowers exercise capacity and reduces myocardial hypertrophy with swimming exercise.

    PubMed

    Horckmans, Michael; Léon-Gómez, Elvira; Robaye, Bernard; Balligand, Jean-Luc; Boeynaems, Jean-Marie; Dessy, Chantal; Communi, Didier

    2012-10-01

    Nucleotides released within the heart under pathological conditions can be involved in cardioprotection or cardiac fibrosis through the activation purinergic P2Y(2) and P2Y(6) receptors, respectively. We previously demonstrated that adult P2Y(4)-null mice display a microcardia phenotype related to a cardiac angiogenic defect. To evaluate the functional consequences of this defect, we performed here a combination of cardiac monitoring and exercise tests. We investigated the exercise capacity of P2Y(4) wild-type and P2Y(4)-null mice in forced swimming and running tests. Analysis of their stress, locomotion, and resignation was realized in open field, black and white box, and tail suspension experiments. Exercise-induced cardiac hypertrophy was evaluated after repeated and prolonged exercise in P2Y(4) wild-type and P2Y(4)-null hearts. We showed that P2Y(4)-null mice have a lower exercise capacity in both swimming and treadmill tests. This was not related to decreased motivation or increased stress, since open field, white and black box, and mouse tail suspension tests gave comparable results in P2Y(4) wild-type and P2Y(4)-null mice. Heart rate and blood pressure rose normally in P2Y(4)-null swimming mice equipped with a telemetric implant. On the contrary, we observed a delayed recovery of postexercise blood pressure after exercise in P2Y(4)-null mice. The heart rate increment in response to catecholamines was also similar in P2Y(4) wild-type and P2Y(4)-null implanted mice, which is consistent with a similar level of cardiac β-receptor expression. Interestingly, the heart of P2Y(4)-null mice displayed a reduced sympathetic innervation associated with a decreased norepinephrine level. We also demonstrated that exercise-induced cardiac hypertrophy was lower in P2Y(4)-null mice after repeated and prolonged exercise. This was associated with a lower increase in cardiomyocyte size and microvessel density. In conclusion, besides its role in cardiac development, P2Y(4

  19. Reduced exercise capacity in patients with tricuspid regurgitation after successful mitral valve replacement for rheumatic mitral valve disease.

    PubMed Central

    Groves, P H; Lewis, N P; Ikram, S; Maire, R; Hall, R J

    1991-01-01

    OBJECTIVE--To determine how severe tricuspid regurgitation influences exercise capacity and functional state in patients who have undergone successful mitral valve replacement for rheumatic mitral valve disease. DESIGN--9 patients in whom clinically significant tricuspid regurgitation developed late after mitral valve replacement were compared with 9 patients with no clinical evidence of tricuspid regurgitation. The two groups were matched for preoperative clinical and haemodynamic variables. Patients were assessed by conventional echocardiography, Doppler echocardiography, and a maximal treadmill exercise test in which expired gas was monitored by mass spectrometry. SETTING--University Hospital of Wales, Cardiff. SUBJECTS--18 patients who had been reviewed regularly since mitral valve replacement. MAIN OUTCOME MEASURE--Objective indices of exercise performance including exercise duration, maximal oxygen consumption, anaerobic threshold, and ventilatory response to exercise. RESULTS--Mitral valve prosthetic function was normal in all patients and estimated pulmonary artery systolic pressure and left ventricular function were similar in the two groups. Right ventricular diameter (median (range) 5.0 (4.3-5.6) v 3.7 (3.0-5.4) cm, p less than 0.01) and the incidence of paradoxical septal motion (9/9 v 3/9, p less than 0.01) were greater in the group with severe tricuspid regurgitation. Exercise performance--assessed by exercise duration (6.3 (5.0-10.7) v 12.7 (7.2-16.0) min, p less than 0.01), maximum oxygen consumption (11.2 (7.3-17.8) v 17.7 (11.8-21.4) ml min-1 kg-1, p less than 0.01), and anaerobic threshold (8.3 (4.6-11.4) v 0.7 (7.3-15.5) ml min-1 kg-1, p less than 0.05)--was significantly reduced in the group with severe tricuspid regurgitation. The ventilatory response to exercise was greater in patients with tricuspid regurgitation (minute ventilation at the same minute carbon dioxide production (41.0 (29.9-59.5) v 33.6 (26.8-39.3) l/min, p less than 0

  20. Ecological immunization: in situ training of free-ranging predatory lizards reduces their vulnerability to invasive toxic prey.

    PubMed

    Ward-Fear, G; Pearson, D J; Brown, G P; Rangers, Balanggarra; Shine, R

    2016-01-01

    In Australia, large native predators are fatally poisoned when they ingest invasive cane toads (Rhinella marina). As a result, the spread of cane toads has caused catastrophic population declines in these predators. Immediately prior to the arrival of toads at a floodplain in the Kimberley region, we induced conditioned taste aversion in free-ranging varanid lizards (Varanus panoptes), by offering them small cane toads. By the end of the 18-month study, only one of 31 untrained lizards had survived longer than 110 days, compared to more than half (nine of 16) of trained lizards; the maximum known survival of a trained lizard in the presence of toads was 482 days. In situ aversion training (releasing small toads in advance of the main invasion front) offers a logistically simple and feasible way to buffer the impact of invasive toads on apex predators. PMID:26740565

  1. Supine Treadmill Exercise in Lower Body Negative Pressure Combined with Resistive Exercise Counteracts Bone Loss, Reduced Aerobic Upright Exercise Capacity and Reduced Muscle Strength

    NASA Technical Reports Server (NTRS)

    Meuche, Sabine; Schneider, S. M.; Lee, S. M. C.; Macias, B. R.; Smith, S. M.; Watenpaugh, D. E.; Hargens, A. R.

    2006-01-01

    Long-term exposure to weightlessness leads to cardiovascular and musculoskeletal deconditioning. In this report, the effectiveness of combined supine treadmill exercise in a lower body negative pressure chamber (LBNPex) and flywheel resistive exercise (Rex) countermeasures was determined to prevent bone loss, reduced aerobic upright exercise capacity and reduced muscle strength. We hypothesized that exercise subjects would show less decrease in bone mineral density (BMD), peak oxygen consumption (VO2pk) and knee extensor strength (KES) than control subjects. Sixteen healthy female subjects participated in a 60-d 6(sup 0) head-down tilt bed rest (BR) study after providing written informed consent. Subjects were assigned to one of two groups: a non-exercising control group CON or an exercise group EX performing LBNPex 2-4 d/wk and Rex every 3rd-d. VO2pk was measured with a maximal, graded, upright treadmill test performed pre-BR and on 3-d after BR. BMD was assessed before and 3-d after BR. Isokinetic KES was measured before and 5-d after BR. Two-way repeated measures ANOVA were performed. Statistical significance was set at p less than 0.05. CON experienced a significant decrease in BMD in the trochanter (PRE: 0.670 plus or minus 0.045; POST: 0.646 plus or minus 0.352 g (raised dot) per square centimeter) and in the whole hip (PRE=0.894 plus or minus 0.059; POST: 0.858 plus or minus 0.057 g (raised dot) per square centimeter). BMD also decreased significantly in EX in the trochanter (PRE: 0.753 plus or minus 0.0617; POST: 0.741 plus or minus 0.061 g (raised dot) per square centimeter) and whole hip (PRE: 0.954 plus or minus 0.067; POST: 0.935 plus or minus 0.069 g (raised dot) per square centimeter). BMD losses were significantly less in EX than in CON subjects. VO2pk was significantly decreased in the CON after BR (PRE: 38.0 plus or minus 4.8; POST: 29.9 plus or minus 4.2 ml (raised dot) per kilogram per minute), but not in the EX (PRE: 39.0 plus or minus 2.0; POST

  2. Non-invasive assessment of phosphate metabolism and oxidative capacity in working skeletal muscle in healthy young Chinese volunteers using 31P Magnetic Resonance Spectroscopy

    PubMed Central

    Wang, Huiting; Wu, Wenbo; Zhang, Xin; Tian, Chuanshuai; Yu, Haiping; Liu, Renyuan; Zhu, Bin

    2016-01-01

    Background. Generally, males display greater strength and muscle capacity than females while performing a task. Muscle biopsy is regarded as the reference method of evaluating muscle functions; however, it is invasive and has sampling errors, and is not practical for longitudinal studies and dynamic measurement during excise. In this study, we built an in-house force control and gauge system for quantitatively applying force to quadriceps while the subjects underwent 31P Magnetic Resonance Spectroscopy (31P-MRS); our aim was to investigate if there is a sex difference of phosphate metabolite change in working muscles in young heathy Chinese volunteers. Methods. Volunteers performed knee-extending excises using a force control and gauge system while lying prone in a Philips 3T Magnetic Resonance (MR) scanner. The 31P-MRS coil was firmly placed under the middle of the quadriceps . 31P-MRS measurements of inorganic phosphate (Pi), phosphocreatine (PCr) and adenosine triphosphate (ATP) were acquired from quadriceps while subjects were in a state of pre-, during- and post-exercise. The PCr, Pi, PCr/Pi, PCr/ATP, pH, work/energy cost ratio (WE), kPCr and oxidative capacity were compared between males and females. Results. A total of 17 volunteers underwent the study. Males: N = 10, age = 23.30 ± 1.25years; females: N = 7, age = 23.57 ± 0.79 years. In this study, males had significantly greater WE (16.33 ± 6.46 vs. 7.82 ± 2.16, p = 0.002) than females. Among PCr, Pi, PCr/Pi, PCr/ATP, pH, kPCr and oxidative capacity at different exercise status, only PCr/Pi (during-exercise, males = 5.630 ± 1.647, females = 4.014 ± 1.298, p = 0.047), PCr/ATP (during-exercise, males =1.273 ± 0.219, females = 1.523 ± 0.167, p = 0.025), and ATP (post-exercise, males = 24.469 ± 3.911 mmol/kg, females = 18.353 ± 4.818 mmol/kg, p = 0.035) had significant sex differences. Males had significantly greater PCr/Pi, but less PCr/ATP than females during exercise, suggesting males had higher

  3. Non-invasive assessment of phosphate metabolism and oxidative capacity in working skeletal muscle in healthy young Chinese volunteers using (31)P Magnetic Resonance Spectroscopy.

    PubMed

    Li, Ming; Chen, Fei; Wang, Huiting; Wu, Wenbo; Zhang, Xin; Tian, Chuanshuai; Yu, Haiping; Liu, Renyuan; Zhu, Bin; Zhang, Bing; Dai, Zhenyu

    2016-01-01

    Background. Generally, males display greater strength and muscle capacity than females while performing a task. Muscle biopsy is regarded as the reference method of evaluating muscle functions; however, it is invasive and has sampling errors, and is not practical for longitudinal studies and dynamic measurement during excise. In this study, we built an in-house force control and gauge system for quantitatively applying force to quadriceps while the subjects underwent (31)P Magnetic Resonance Spectroscopy ((31)P-MRS); our aim was to investigate if there is a sex difference of phosphate metabolite change in working muscles in young heathy Chinese volunteers. Methods. Volunteers performed knee-extending excises using a force control and gauge system while lying prone in a Philips 3T Magnetic Resonance (MR) scanner. The (31)P-MRS coil was firmly placed under the middle of the quadriceps . (31)P-MRS measurements of inorganic phosphate (Pi), phosphocreatine (PCr) and adenosine triphosphate (ATP) were acquired from quadriceps while subjects were in a state of pre-, during- and post-exercise. The PCr, Pi, PCr/Pi, PCr/ATP, pH, work/energy cost ratio (WE), kPCr and oxidative capacity were compared between males and females. Results. A total of 17 volunteers underwent the study. Males: N = 10, age = 23.30 ± 1.25years; females: N = 7, age = 23.57 ± 0.79 years. In this study, males had significantly greater WE (16.33 ± 6.46 vs. 7.82 ± 2.16, p = 0.002) than females. Among PCr, Pi, PCr/Pi, PCr/ATP, pH, kPCr and oxidative capacity at different exercise status, only PCr/Pi (during-exercise, males = 5.630 ± 1.647, females = 4.014 ± 1.298, p = 0.047), PCr/ATP (during-exercise, males =1.273 ± 0.219, females = 1.523 ± 0.167, p = 0.025), and ATP (post-exercise, males = 24.469 ± 3.911 mmol/kg, females = 18.353 ± 4.818 mmol/kg, p = 0.035) had significant sex differences. Males had significantly greater PCr/Pi, but less PCr/ATP than females during exercise, suggesting males had

  4. Does salinity reduce growth in maize root epidermal cells by inhibiting their capacity for cell wall acidification?

    PubMed

    Zidan, I; Azaizeh, H; Neumann, P M

    1990-05-01

    The reduction in growth of maize (Zea mays L.) seedling primary roots induced by salinization of the nutrient medium with 100 millimolar NaCl was accompanied by reductions in the length of the root tip elongation zone, the length of fully elongated epidermal cells, and the apparent rate of cell production: Each was partially restored when calcium levels in the salinized growth medium were increased from 0.5 to 10.0 millimolar. We investigated the possibility that the inhibition of elongation growth by salinity might be associated with an inhibition of cell wall acidification, such as that which occurs when root growth is inhibited by IAA. A qualitative assay of root surface acidification, using bromocresol purple pH indicator in agar, showed that salinized roots, with and without extra calcium, produced a zone of surface acidification which was similar to that produced by control roots. The zone of acidification began 1 to 2 millimeters behind the tip and coincided with the zone of cell elongation. The remainder of the root alkalinized its surface. Kinetics of surface acidification were assayed quantitatively by placing a flat tipped pH electrode in contact with the elongation zone. The pH at the epidermal surfaces of roots grown either with 100 millimolar NaCl (growth inhibitory), or with 10 millimolar calcium +/- NaCl (little growth inhibition), declined from 6.0 to 5.1 over 30 minutes. We conclude that NaCl did not inhibit growth by reducing the capacity of epidermal cells to acidify their walls. PMID:16667468

  5. Development of Dive Capacity in Northern Elephant Seals (Mirounga angustirostris): Reduced Body Reserves at Weaning Are Associated with Elevated Body Oxygen Stores during the Postweaning Fast.

    PubMed

    Somo, Derek A; Ensminger, David C; Sharick, Jeffrey T; Kanatous, Shane B; Crocker, Daniel E

    2015-01-01

    Developmental increases in dive capacity have been reported in numerous species of air-breathing marine vertebrates. Previous studies in juvenile phocid seals suggest that increases in physiological dive capacity during the postweaning fast (PWF) are critical to support independent aquatic foraging. Although there is a strong relationship between size at weaning and PWF duration and body reserves at weaning vary considerably, few studies have considered whether such variation in body reserve magnitude promotes phenotypic modulation of dive capacity development during the PWF. Phenotypic modulation, a form of developmental plasticity in which rates and degrees of expression of the developmental program are modulated by environmental factors, may enhance diving capacity in weanlings with reduced PWF durations due to smaller body reserves at weaning if reduced body reserves promote accelerated development of dive capacity. We longitudinally measured changes in blood and muscle oxygen stores and muscle metabolic enzymes over the first 8 wk of the PWF in northern elephant seals and determined whether rates of change in these parameters varied with body reserves at weaning. We assessed whether erythropoietin (EPO), thyroid hormones, serum nonesterified fatty acid levels, and iron status influenced blood and muscle oxygen store development or were influenced by body reserves at weaning. Although mass-specific plasma volume and blood volume were relatively stable across the fast, both were elevated in animals with reduced body reserves. Surprisingly, hemoglobin and mean corpuscular hemoglobin concentrations declined over the PWF while hematocrit remained stable, and these variables were not associated with body reserves or EPO. Swimming muscle myoglobin and serum iron levels increased rapidly early in the PWF and were not related to body reserves. Patterns in maximal activities of muscle enzymes suggested a decline in total aerobic and anaerobic metabolic capacity over the

  6. A novel cantharidin analog N-Benzylcantharidinamide reduces the expression of MMP-9 and invasive potentials of Hep3B via inhibiting cytosolic translocation of HuR

    SciTech Connect

    Lee, Ji-Yeon; Chung, Tae-Wook; Choi, Hee-Jung; Lee, Chang Hyun; Eun, Jae Soon; Han, Young Taek; Choi, Jun-Yong; Kim, So-Yeon; Han, Chang-Woo; Jeong, Han-Sol; Ha, Ki-Tae

    2014-05-02

    Highlights: • We examined the inhibition of N-Benzylcantharidinamide on MMP-9-mediated invasion. • Unlike cantharidin, N-Benzylcantharidinamide has very low toxicity on Hep3B cells. • The reduced MMP-9 expression was due to HuR-mediated decrease of mRNA stability. • We suggest N-Benzylcantharidinamide as a novel inhibitor of MMP-9-related invasion. - Abstract: Invasion and metastasis are major causes of malignant tumor-associated mortality. The present study aimed to investigate the molecular events underlying inhibitory effect of N-Benzylcantharidinamide, a novel synthetic analog of cantharidin, on matrix metalloproteinase-9 (MMP-9)-mediated invasion in highly metastatic hepatocellular carcinoma Hep3B cells. In this investigation, among six analogs of cantharidin, only N-Benzylcantharidinamide has the inhibitory action on MMP-9 expression at non-toxic dose. The MMP-9 expression and invasion of Hep3B cells were significantly suppressed by treatment of N-Benzylcantharidinamide in a dose-dependent manner. On the other hand, the transcriptional activity of MMP-9 promoter and nuclear levels of NF-κB and AP-1 as the main transcriptional factors inducing MMP-9 expression were not affected by it although the level of MMP-9 mRNA was reduced by treatment of N-Benzylcantharidinamide. Interestingly, the stability of MMP-9 mRNA was significantly reduced by N-Benzylcantharidinamide-treatment. In addition, the cytosolic translocation of human antigen R (HuR), which results in the increase of MMP-9 mRNA stability through interaction of HuR with 3′-untranslated region of MMP-9 mRNA, was suppressed by treatment of N-Benzylcantharidinamide, in a dose-dependent manner. Taken together, it was demonstrated, for the first time, that N-Benzylcantharidinamide suppresses MMP-9 expression by reducing HuR-mediated MMP-9 mRNA stability for the inhibition of invasive potential in highly metastatic Hep3B cells.

  7. Rhamnus cathartica (Rosales: Rhamnaceae) Invasion Reduces Ground-Dwelling Insect Abundance and Diversity in Northeast Iowa Forests.

    PubMed

    Schuh, Marissa; Larsen, Kirk J

    2015-06-01

    European buckthorn (Rhamnus cathartica L.) is an invasive woody shrub in deciduous forests of the Upper Midwest. Studies have suggested buckthorn invasion has negative effects on native plants, soil, and ecosystems, but its impacts on insects are largely unstudied. To test the impact of buckthorn invasion on ground-dwelling insects in forests of northeastern Iowa, pitfall traps were used to sample ground-dwelling insects at five sites four different periods from June to August 2013. Each site had three treatments: areas heavily infested with buckthorn, areas where buckthorn has not established, and areas where buckthorn had been removed within the past 2-10 yr. Most insects were identified to family and quantified; while ground beetles (Coleoptera: Carabidae) and ants (Hymenoptera: Formicidae) were identified to species and quantified. In total, 11,576 insects representing eight orders and 46 families were collected. Areas uninvaded by buckthorn had significantly greater insect abundance and taxonomic richness than areas invaded by buckthorn. Of the 948 ground beetles representing 40 species, abundance, species richness, and Shannon diversity indices were significantly lower in areas invaded by buckthorn compared with areas with no buckthorn. The 2,661 ants from 24 species had similar trends, but treatment differences were not significant because of high variability. These results clearly show a negative impact of buckthorn invasion on the abundance and taxonomic richness of ground-dwelling insects. PMID:26313971

  8. Reduced Expression of Enac in Placenta Tissues of Patients with Severe Preeclampsia Is Related to Compromised Trophoblastic Cell Migration and Invasion during Pregnancy

    PubMed Central

    Yang, Yue; Liu, Ying; Diao, Ruiying; Sheng, Kai; Liu, Xinghui; Xu, Wenming

    2013-01-01

    The purpose of the study is to investigate the expression of epithelial sodium channel (ENaC) in normal pregnancy and severe preeclampsia placenta and to explore the underlying mechanism of the relationship between the altered ENaC expression and onset of preeclampsia. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to check epithelial sodium channel subunits expression in mRNA and protein level in first term and full term placental tissue. ENaCα specific RNAi were used to knockdown ENaC expression and cell invasion and migration assay were used to check whether reduced expression of ENaC can compromise trophoblast cell function. The result showed that ENaCα was highly expressed in first term placental trophoblast cells; while EnaCβ was highly expressed in full term placenta. Knockdown ENaCα expression by using small interfering RNA reduced the invasive and migration abilities of HTR-8/SVneo cell. Real time-PCR and Western blot analysis showed that the expression levels of ENaCβ were also significantly lower in severe preeclampsia compared with normal pregnancy. It is concluded that the ENaC played an important role in trophoblast cell invasion and migration. Reduced expression and activity of epithelial sodium channel in trophoblast cells may be involved in the pathogenesis of preeclampsia. PMID:23977235

  9. Environmental consequences of invasive species: greenhouse gas emissions of insecticide use and the role of biological control in reducing emissions.

    PubMed

    Heimpel, George E; Yang, Yi; Hill, Jason D; Ragsdale, David W

    2013-01-01

    Greenhouse gas emissions associated with pesticide applications against invasive species constitute an environmental cost of species invasions that has remained largely unrecognized. Here we calculate greenhouse gas emissions associated with the invasion of an agricultural pest from Asia to North America. The soybean aphid, Aphis glycines, was first discovered in North America in 2000, and has led to a substantial increase in insecticide use in soybeans. We estimate that the manufacture, transport, and application of insecticides against soybean aphid results in approximately 10.6 kg of carbon dioxide (CO2) equivalent greenhouse gasses being emitted per hectare of soybeans treated. Given the acreage sprayed, this has led to annual emissions of between 6 and 40 million kg of CO2 equivalent greenhouse gasses in the United States since the invasion of soybean aphid, depending on pest population size. Emissions would be higher were it not for the development of a threshold aphid density below which farmers are advised not to spray. Without a threshold, farmers tend to spray preemptively and the threshold allows farmers to take advantage of naturally occurring biological control of the soybean aphid, which can be substantial. We find that adoption of the soybean aphid economic threshold can lead to emission reductions of approximately 300 million kg of CO2 equivalent greenhouse gases per year in the United States. Previous studies have documented that biological control agents such as lady beetles are capable of suppressing aphid densities below this threshold in over half of the soybean acreage in the U.S. Given the acreages involved this suggests that biological control results in annual emission reductions of over 200 million kg of CO2 equivalents. These analyses show how interactions between invasive species and organisms that suppress them can interact to affect greenhouse gas emissions. PMID:23977273

  10. Environmental Consequences of Invasive Species: Greenhouse Gas Emissions of Insecticide Use and the Role of Biological Control in Reducing Emissions

    PubMed Central

    Heimpel, George E.; Yang, Yi; Hill, Jason D.; Ragsdale, David W.

    2013-01-01

    Greenhouse gas emissions associated with pesticide applications against invasive species constitute an environmental cost of species invasions that has remained largely unrecognized. Here we calculate greenhouse gas emissions associated with the invasion of an agricultural pest from Asia to North America. The soybean aphid, Aphis glycines, was first discovered in North America in 2000, and has led to a substantial increase in insecticide use in soybeans. We estimate that the manufacture, transport, and application of insecticides against soybean aphid results in approximately 10.6 kg of carbon dioxide (CO2) equivalent greenhouse gasses being emitted per hectare of soybeans treated. Given the acreage sprayed, this has led to annual emissions of between 6 and 40 million kg of CO2 equivalent greenhouse gasses in the United States since the invasion of soybean aphid, depending on pest population size. Emissions would be higher were it not for the development of a threshold aphid density below which farmers are advised not to spray. Without a threshold, farmers tend to spray preemptively and the threshold allows farmers to take advantage of naturally occurring biological control of the soybean aphid, which can be substantial. We find that adoption of the soybean aphid economic threshold can lead to emission reductions of approximately 300 million kg of CO2 equivalent greenhouse gases per year in the United States. Previous studies have documented that biological control agents such as lady beetles are capable of suppressing aphid densities below this threshold in over half of the soybean acreage in the U.S. Given the acreages involved this suggests that biological control results in annual emission reductions of over 200 million kg of CO2 equivalents. These analyses show how interactions between invasive species and organisms that suppress them can interact to affect greenhouse gas emissions. PMID:23977273

  11. Fish Oil Contaminated with Persistent Organic Pollutants Reduces Antioxidant Capacity and Induces Oxidative Stress without Affecting Its Capacity to Lower Lipid Concentrations and Systemic Inflammation in Rats123

    PubMed Central

    Hong, Mee Young; Lumibao, Jan; Mistry, Prashila; Saleh, Rhonda; Hoh, Eunha

    2015-01-01

    Background: Numerous studies have investigated the benefits of fish, fish oil, and ω-3 (n–3) polyunsaturated fatty acids against cardiovascular diseases. However, concern surrounding contamination with persistent organic pollutants (POPs) prompts caution in the recommendation to consume fish and fish oil. Objective: The present study compared the effects of fish oil contaminated with polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs) on serum lipid profiles, inflammation, and oxidative stress. Methods: Twenty eight-day-old male Sprague-Dawley rats (n = 30) consumed diets of unmodified fish oil (FO) consisting of 15% fat by weight, persistent organic pollutant–contaminated fish oil (POP FO) (PCBs at 2.40 μg/g; OCs at 3.80 μg/g FO), or corn oil (control; CO) for 9 wk. Lipid profiles and C-reactive protein concentrations were assessed. Hepatic gene expression related to lipid metabolism was determined by real time quantitative polymerase chain reaction analysis. Results: After 9 wk of feeding, accumulation of PCBs and OCs in the fat tissue of the POP FO group compared with the other 2 groups was confirmed (P < 0.01). Both fish oil groups showed greater HDL cholesterol (FO 53 ± 5.3 and POP FO 55 ± 7.7 vs. CO 34 ± 2.3 mg/dL), but lower triglycerides (24 ± 2.8 and 22 ± 3.0 vs. 43 ± 5.6 mg/dL), LDL cholesterol (38 ± 14 and 34 ± 9.2 vs. 67 ± 4.4 mg/dL), and C-reactive protein (113 ± 20 and 120 ± 26 vs. 189 ± 22 μg/dL) compared with the CO group (P < 0.05). Gene expression of fatty acid synthase in both fish oil groups was also less than in the CO group (P < 0.05). However, the POP FO group showed greater lipid peroxidation (5.1 ± 0.7 vs. 2.9 ± 0.9 and 2.6 ± 0.6 μM) and less antioxidant capacity (0.08 ± 0.06 vs. 0.5 ± 0.1 and 0.4 ± 0.1 mM) than the CO and FO groups (P < 0.05). Conclusions: These findings indicate that, despite exhibiting benefits on serum lipid concentrations and inflammation, contamination with PCBs and OCs

  12. High GPX1 expression promotes esophageal squamous cell carcinoma invasion, migration, proliferation and cisplatin-resistance but can be reduced by vitamin D

    PubMed Central

    Gan, Xiangfeng; Chen, Baishen; Shen, Zhuojian; Liu, Yeqing; Li, Haifeng; Xie, Xuan; Xu, Xia; Li, Haigang; Huang, Zhiquan; Chen, Ju

    2014-01-01

    Esophageal cancer is one of the most common cancers worldwide. Despite recent progress in the development of novel therapies, esophageal carcinoma remains an aggressive cancer associated with a poor prognosis. The glutathione peroxidase 1 (GPX1) gene located on chromosome 3p21.3 is associated with the cancer of several organs. According to available information, GPX1, a gene downstream of NF-κB, is considered to exert adverse effects on tumour progression and enhance malignancy in some cancers but has not been reported in esophageal cancer. It is also reported that vitamin D (Vit. D), a widely used drug in the clinical setting, could suppress GPX1 expression through the NF-κB pathway. Thus, it is speculated that Vit. D could reduce malignancy in esophageal cancer by altering the NF-κB pathway. In this study, we confirmed our speculation by finding that Vit. D, through the inhibition of GPX1, decreased the migratory, invasive and proliferative capabilities, as well as cisplatin resistance, in esophageal cancer cells. Furthermore, when invasion and migration were reduced in the GPX1-inhibited cells, the expression of urokinase type plasminogen activator (uPA) and matrix metalloproteinase-2 (MMP2) was also suppressed correspondingly. Therefore, we believe that, in esophageal cancer cells, the expression of GPX1 can promote invasion, migration, proliferation and cisplatin resistance, and Vit. D can reduce the associated malignancy through the NF-κB pathway. The Vit. D- and NF-κB-mediated decrease in GPX1 expression resulted in a decrease in MMP2- and uPA-mediated invasion and migration. PMID:25356106

  13. Reducing follow-ups: an opportunity to increase the capacity of genitourinary medicine services across the UK.

    PubMed

    Ahmed-Jushuf, I; Griffiths, V

    2007-05-01

    Significant increases in genitourinary (GU) medicine clinic workloads throughout the UK have resulted in an unmet demand for appointments, and increased waiting times. In order to meet the government target of a 48-hour maximum waiting time for all patients, many clinics are modernising current practices to increase capacity and improve access to services. The 'Six Sigma' study group of 12 GU medicine clinics which was formed in 2003 to investigate means of enhancing capacity of GU medicine services, has demonstrated that there is a significant amount of unreleased capacity within UK clinics. In this article, the Six Sigma group present potential actions which other GU medicine clinics in the UK may be able to apply and thereby release additional capacity. Example case studies from the Six Sigma study are also presented, illustrating the applicability of this model throughout the UK. The findings of the Six Sigma project offer GU medicine clinics across the UK the opportunity to increase capacity, without adversely affecting quality of care. PMID:17524188

  14. Effects of reducing temperatures on the hydrogen storage capacity of double-walled carbon nanotubes with Pd loading.

    PubMed

    Sheng, Qu; Wu, Huimin; Wexler, David; Liu, Huakun

    2014-06-01

    The effects of different temperatures on the hydrogen sorption characteristics of double-walled carbon nanotubes (DWCNTs) with palladium loading have been investigated. When we use different temperatures, the particle sizes and specific surface areas of the samples are different, which affects the hydrogen storage capacity of the DWCNTs. In this work, the amount of hydrogen storage capacity was determined (by AMC Gas Reactor Controller) to be 1.70, 1.85, 2.00, and 1.93 wt% for pristine DWCNTS and for 2%Pd/DWCNTs-300 degrees C, 2%Pd/DWCNTs-400 degrees C, and 2%Pd/DWCNTs-500 degrees C, respectively. We found that the hydrogen storage capacity can be enhanced by loading with 2% Pd nanoparticles and selecting a suitable temperature. Furthermore, the sorption can be attributed to the chemical reaction between atomic hydrogen and the dangling bonds of the DWCNTs. PMID:24738450

  15. Vitamin E-enriched diet reduces adaptive responses to training determining respiratory capacity and redox homeostasis in rat heart.

    PubMed

    Venditti, Paola; Napolitano, Gaetana; Barone, Daniela; Pervito, Emanuela; Di Meo, Sergio

    2016-01-01

    We investigated whether reactive oxygen species (ROS) are involved in heart adaptive responses administering a vitamin E-enriched diet to trained rats. Using the homogenates and/or mitochondria from rat hearts we determined the aerobic capacity, tissue level of mitochondrial proteins, and expression of cytochrome c and factors (PGC-1, NRF-1, and NRF-2) involved in mitochondrial biogenesis. We also determined the oxidative damage, glutathione peroxidase (GPX) and reductase activities, glutathione content, mitochondrial ROS release rate, and susceptibility to in vitro oxidative challenge. Glutathione (GSH) content was not affected by both training and antioxidant supplementation. Conversely, antioxidant supplementation prevented metabolic adaptations to training, such as the increases in oxidative capacity, tissue content of mitochondrial proteins, and cytochrome c expression, attenuated some protective adaptations, such as the increase in antioxidant enzyme activities, and did not modify the decrease in ROS release by succinate supplemented mitochondria. Moreover, vitamin E prevented the training-linked increase in tissue capacity to oppose an oxidative attach. The antioxidant effects were associated with decreased levels of PGC-1, NRF-1, and NRF-2 expression. Our results support the idea that some heart adaptive responses to training depend on ROS produced during the exercise sessions and are mediated by the increase in PGC-1 expression which is involved in both the regulation of respiratory capacity and antioxidant protection. However, vitamin inability to prevent some adaptations suggests that other signaling pathways impinging on PGC-1 can modify the response to the antioxidant integration. PMID:26467971

  16. Deletion of inositol hexakisphosphate kinase 1 (IP6K1) reduces cell migration and invasion, conferring protection from aerodigestive tract carcinoma in mice.

    PubMed

    Jadav, Rathan S; Kumar, Dharmika; Buwa, Natasha; Ganguli, Shubhra; Thampatty, Sitalakshmi R; Balasubramanian, Nagaraj; Bhandari, Rashna

    2016-08-01

    Inositol hexakisphosphate kinases (IP6Ks), a family of enzymes found in all eukaryotes, are responsible for the synthesis of 5-diphosphoinositol pentakisphosphate (5-IP7) from inositol hexakisphosphate (IP6). Three isoforms of IP6Ks are found in mammals, and gene deletions of each isoform lead to diverse, non-overlapping phenotypes in mice. Previous studies show a facilitatory role for IP6K2 in cell migration and invasion, properties that are essential for the early stages of tumorigenesis. However, IP6K2 also has an essential role in cancer cell apoptosis, and mice lacking this protein are more susceptible to the development of aerodigestive tract carcinoma upon treatment with the oral carcinogen 4-nitroquinoline-1-oxide (4NQO). Not much is known about the functions of the equally abundant and ubiquitously expressed IP6K1 isoform in cell migration, invasion and cancer progression. We conducted a gene expression analysis on mouse embryonic fibroblasts (MEFs) lacking IP6K1, revealing a role for this protein in cell receptor-extracellular matrix interactions that regulate actin cytoskeleton dynamics. Consequently, cells lacking IP6K1 manifest defects in adhesion-dependent signaling, evident by lower FAK and Paxillin activation, leading to reduced cell spreading and migration. Expression of active, but not inactive IP6K1 reverses migration defects in IP6K1 knockout MEFs, suggesting that 5-IP7 synthesis by IP6K1 promotes cell locomotion. Actin cytoskeleton remodeling and cell migration support the ability of cancer cells to achieve their complete oncogenic potential. Cancer cells with lower IP6K1 levels display reduced migration, invasion, and anchorage-independent growth. When fed an oral carcinogen, mice lacking IP6K1 show reduced progression from epithelial dysplasia to invasive carcinoma. Thus, our data reveal that like IP6K2, IP6K1 is also involved in early cytoskeleton remodeling events during cancer progression. However, unlike IP6K2, IP6K1 is essential for 4NQO

  17. Selenium exposure results in reduced reproduction in an invasive ant species and altered competitive behavior for a native ant species.

    PubMed

    De La Riva, Deborah G; Trumble, John T

    2016-06-01

    Competitive ability and numerical dominance are important factors contributing to the ability of invasive ant species to establish and expand their ranges in new habitats. However, few studies have investigated the impact of environmental contamination on competitive behavior in ants as a potential factor influencing dynamics between invasive and native ant species. Here we investigated the widespread contaminant selenium to investigate its potential influence on invasion by the exotic Argentine ant, Linepithema humile, through effects on reproduction and competitive behavior. For the fecundity experiment, treatments were provided to Argentine ant colonies via to sugar water solutions containing one of three concentrations of selenium (0, 5 and 10 μg Se mL(-1)) that fall within the range found in soil and plants growing in contaminated areas. Competition experiments included both the Argentine ant and the native Dorymyrmex bicolor to determine the impact of selenium exposure (0 or 15 μg Se mL(-1)) on exploitation- and interference-competition between ant species. The results of the fecundity experiment revealed that selenium negatively impacted queen survival and brood production of Argentine ants. Viability of the developing brood was also affected in that offspring reached adulthood only in colonies that were not given selenium, whereas those in treated colonies died in their larval stages. Selenium exposure did not alter direct competitive behaviors for either species, but selenium exposure contributed to an increased bait discovery time for D. bicolor. Our results suggest that environmental toxins may not only pose problems for native ant species, but may also serve as a potential obstacle for establishment among exotic species. PMID:27038576

  18. Reduced Genetic Diversity and Increased Structure in American Mink on the Swedish Coast following Invasive Species Control.

    PubMed

    Zalewski, Andrzej; Zalewska, Hanna; Lunneryd, Sven-Gunnar; André, Carl; Mikusiński, Grzegorz

    2016-01-01

    Eradication and population reductions are often used to mitigate the negative impacts of non-native invasive species on native biodiversity. However, monitoring the effectiveness of non-native species control programmes is necessary to evaluate the efficacy of these measures. Genetic monitoring could provide valuable insights into temporal changes in demographic, ecological, and evolutionary processes in invasive populations being subject to control programmes. Such programmes should cause a decrease in effective population size and/or in genetic diversity of the targeted non-native species and an increase in population genetic structuring over time. We used microsatellite DNA data from American mink (Neovison vison) to determine whether the removal of this predator on the Koster Islands archipelago and the nearby Swedish mainland affected genetic variation over six consecutive years of mink culling by trappers as part of a population control programme. We found that on Koster Islands allelic richness decreased (from on average 4.53 to 3.55), genetic structuring increased, and effective population size did not change. In contrast, the mink population from the Swedish coast showed no changes in genetic diversity or structure, suggesting the stability of this population over 6 years of culling. Effective population size did not change over time but was higher on the coast than on the islands across all years. Migration rates from the islands to the coast were almost two times higher than from the coast to the islands. Most migrants leaving the coast were localised on the southern edge of the archipelago, as expected from the direction of the sea current between the two sites. Genetic monitoring provided valuable information on temporal changes in the population of American mink suggesting that this approach can be used to evaluate and improve control programmes of invasive vertebrates. PMID:27333328

  19. Reduced Genetic Diversity and Increased Structure in American Mink on the Swedish Coast following Invasive Species Control

    PubMed Central

    Zalewska, Hanna; Lunneryd, Sven-Gunnar; André, Carl; Mikusiński, Grzegorz

    2016-01-01

    Eradication and population reductions are often used to mitigate the negative impacts of non-native invasive species on native biodiversity. However, monitoring the effectiveness of non-native species control programmes is necessary to evaluate the efficacy of these measures. Genetic monitoring could provide valuable insights into temporal changes in demographic, ecological, and evolutionary processes in invasive populations being subject to control programmes. Such programmes should cause a decrease in effective population size and/or in genetic diversity of the targeted non-native species and an increase in population genetic structuring over time. We used microsatellite DNA data from American mink (Neovison vison) to determine whether the removal of this predator on the Koster Islands archipelago and the nearby Swedish mainland affected genetic variation over six consecutive years of mink culling by trappers as part of a population control programme. We found that on Koster Islands allelic richness decreased (from on average 4.53 to 3.55), genetic structuring increased, and effective population size did not change. In contrast, the mink population from the Swedish coast showed no changes in genetic diversity or structure, suggesting the stability of this population over 6 years of culling. Effective population size did not change over time but was higher on the coast than on the islands across all years. Migration rates from the islands to the coast were almost two times higher than from the coast to the islands. Most migrants leaving the coast were localised on the southern edge of the archipelago, as expected from the direction of the sea current between the two sites. Genetic monitoring provided valuable information on temporal changes in the population of American mink suggesting that this approach can be used to evaluate and improve control programmes of invasive vertebrates. PMID:27333328

  20. N-myc downstream regulated gene 2 overexpression reduces matrix metalloproteinase-2 and -9 activities and cell invasion of A549 lung cancer cell line in vitro

    PubMed Central

    Faraji, Seyed Nooredin; Mojtahedi, Zahra; Ghalamfarsa, Ghasem; Takhshid, Mohammad Ali

    2015-01-01

    Objective(s): N-myc downstream regulated gene 2 (NDRG2) is a candidate gene for tumor suppression. The expression of NDRG2 is down-regulated in several tumors including lung cancer. The aim of this study was to explore the effect of NDRG2 overexpression on invasion, migration, and enzymatic activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in human lung adenocarcinoma A549 cells. Materials and Methods: A recombinant plasmid encoding green fluorescent protein (GFP)-tagged NDRG2 (pCMV6-AC-NDRG2-GFP) was used to overexpress GFP-tagged NDRG2 in A549 cells. The cells in the experimental group and those in the control group were transfected with pCMV6-AC-NDRG2-GFP and a control plasmid without NDRG2 (pCMV6-AC-GFP), respectively. Fluorescent microscopy and flowcytometry analysis of GFP expression were used to evaluate the cellular expression of GFP-tagged NDRG2 and the efficiency of transfection. The effects of NDRG2 expression on cell invasion and migration were evaluated using transwell filter migration assay. The gelatinase activity of secreted MMP-2 and MMP-9 was measured by gelatin zymography. Results: Our results demonstrated the expression of GFP-tagged NDRG2 in the cytoplasm and nucleus of A549 cells. The findings of transwell assay showed that NDRG2 overexpression reduced migration and invasion of A549 cells compared to control cells. Gelatin zymography analyses revealed that NDRG2 overexpression decreased the gelatinase activity of secreted MMP-2 and MMP-9. Conclusion: These findings suggest that NDRG2 may be a new anti-invasion factor in lung cancer that inhibits MMPs activities. PMID:26557966

  1. A regime of two intravenous injections of tranexamic acid reduces blood loss in minimally invasive total hip arthroplasty: a prospective randomised double-blind study.

    PubMed

    Hsu, C-H; Lin, P-C; Kuo, F-C; Wang, J-W

    2015-07-01

    Tranexamic acid (TXA), an inhibitor of fibrinolysis, reduces blood loss after total knee arthroplasty. However, its effect on minimally invasive total hip arthroplasty (THA) is not clear. We performed a prospective, randomised double-blind study to evaluate the effect of two intravenous injections of TXA on blood loss in patients undergoing minimally invasive THA. In total, 60 patients (35 women and 25 men with a mean age of 58.1 years; 17 to 84) who underwent unilateral minimally invasive uncemented THA were randomly divided into the study group (30 patients, 20 women and ten men with a mean age of 56.5 years; 17 to 79) that received two intravenous injections 1 g of TXA pre- and post-operatively (TXA group), and a placebo group (30 patients, 15 women and 15 men with a mean age of 59.5 years; 23 to 84). We compared the peri-operative blood loss of the two groups. Actual blood loss was calculated from the maximum reduction in the level of haemoglobin. All patients were followed clinically for the presence of venous thromboembolism. The TXA group had a lower mean intra-operative blood loss of 441 ml (150 to 800) versus 615 ml (50 to 1580) in the placebo (p = 0.044), lower mean post-operative blood loss (285 ml (120 to 570) versus 392 ml (126 to 660) (p = 0.002), lower mean total blood loss (1070 ml (688 to 1478) versus 1337 ml (495 to 2238) (p = 0.004) and lower requirement for transfusion (p = 0.021). No patients in either group had symptoms of venous thromboembolism or wound complications. This prospective, randomised controlled study showed that a regimen of two intravenous injections of 1 g TXA is effective for blood conservation after minimally invasive THA. PMID:26130344

  2. Vitamin B-6 Supplementation Could Mediate Antioxidant Capacity by Reducing Plasma Homocysteine Concentration in Patients with Hepatocellular Carcinoma after Tumor Resection

    PubMed Central

    Cheng, Shao-Bin; Lin, Ping-Ting; Liu, Hsiao-Tien; Peng, Yi-Shan; Huang, Shih-Chien

    2016-01-01

    Vitamin B-6 has a strong antioxidative effect. It would be useful to determine whether vitamin B-6 supplementation had effects on antioxidant capacities in patients with hepatocellular carcinoma (HCC) who had recently undergone tumor resection. Thirty-three HCC patients were randomly assigned to either the placebo (n = 16) group or the vitamin B-6 50 mg/d (n = 17) group for 12 weeks. Plasma pyridoxal 5′-phosphate, homocysteine, indicators of oxidative stress, and antioxidant capacities were measured. Plasma homocysteine in the vitamin B-6 group was significantly decreased at week 12, while the level of trolox equivalent antioxidant capacity (TEAC) was significantly increased at the end of the intervention period. Vitamin B-6 supplementation had a significant reducing effect on the change of plasma homocysteine (β = −2.4, p = 0.02) but not on the change of TEAC level after adjusting for potential confounders. The change of plasma homocysteine was significantly associated with the change of TEAC after adjusting for potential confounders (β = −162.0, p = 0.03). Vitamin B-6 supplementation seemed to mediate antioxidant capacity via reducing plasma homocysteine rather than having a direct antioxidative effect in HCC patients who had recently undergone tumor resection. The clinical trial number is NCT01964001, ClinicalTrials.gov. PMID:27051670

  3. Vitamin B-6 Supplementation Could Mediate Antioxidant Capacity by Reducing Plasma Homocysteine Concentration in Patients with Hepatocellular Carcinoma after Tumor Resection.

    PubMed

    Cheng, Shao-Bin; Lin, Ping-Ting; Liu, Hsiao-Tien; Peng, Yi-Shan; Huang, Shih-Chien; Huang, Yi-Chia

    2016-01-01

    Vitamin B-6 has a strong antioxidative effect. It would be useful to determine whether vitamin B-6 supplementation had effects on antioxidant capacities in patients with hepatocellular carcinoma (HCC) who had recently undergone tumor resection. Thirty-three HCC patients were randomly assigned to either the placebo (n = 16) group or the vitamin B-6 50 mg/d (n = 17) group for 12 weeks. Plasma pyridoxal 5'-phosphate, homocysteine, indicators of oxidative stress, and antioxidant capacities were measured. Plasma homocysteine in the vitamin B-6 group was significantly decreased at week 12, while the level of trolox equivalent antioxidant capacity (TEAC) was significantly increased at the end of the intervention period. Vitamin B-6 supplementation had a significant reducing effect on the change of plasma homocysteine (β = -2.4, p = 0.02) but not on the change of TEAC level after adjusting for potential confounders. The change of plasma homocysteine was significantly associated with the change of TEAC after adjusting for potential confounders (β = -162.0, p = 0.03). Vitamin B-6 supplementation seemed to mediate antioxidant capacity via reducing plasma homocysteine rather than having a direct antioxidative effect in HCC patients who had recently undergone tumor resection. The clinical trial number is NCT01964001, ClinicalTrials.gov. PMID:27051670

  4. Reduced DNA double-strand break repair capacity and risk of squamous cell carcinoma of the head and neck-A case-control study.

    PubMed

    Liu, Zhensheng; Liu, Hongliang; Gao, Fengqin; Dahlstrom, Kristina R; Sturgis, Erich M; Wei, Qingyi

    2016-04-01

    Tobacco smoke and alcohol use play important roles in the etiology of squamous cell carcinoma of the head and neck (SCCHN). Smoking causes DNA damage, including double-strand DNA breaks (DSBs), that leads to carcinogenesis. To test the hypothesis that suboptimal DSB repair capacity is associated with risk of SCCHN, we applied a flow cytometry-based method to detect the DSB repair phenotype first in four EBV-immortalized human lymphoblastoid cell lines and then in human peripheral blood T-lymphocytes (PBTLs). With this blood-based laboratory assay, we conducted a pilot case-control study of 100 patients with newly diagnosed, previously untreated SCCHN and 124 cancer-free controls of non-Hispanic whites. We found that the mean DSB repair capacity level was significantly lower in cases (42.1%) than that in controls (54.4%) (P<0.001). When we used the median DSB repair capacity level in the controls as the cutoff value for calculating the odds ratios (ORs) with adjustment for age, sex, smoking and drinking status, the cases were more likely than the controls to have a reduced DSB repair capacity (adjusted OR=1.93; 95% confidence interval, CI=1.04-3.56, P=0.037), especially for those subjects who were ever drinkers (adjusted OR=2.73; 95% CI=1.17-6.35, P=0.020) and had oropharyngeal tumors (adjusted OR=2.17; 95% CI=1.06-4.45, P=0.035). In conclusion, these findings suggest that individuals with a reduced DSB repair capacity may be at an increased risk of developing SCCHN. Larger studies are warranted to confirm these preliminary findings. PMID:26963119

  5. Serotype changes in adult invasive pneumococcal infections in Portugal did not reduce the high fraction of potentially vaccine preventable infections.

    PubMed

    Horácio, Andreia N; Diamantino-Miranda, Jorge; Aguiar, Sandra I; Ramirez, Mário; Melo-Cristino, José

    2012-01-01

    We determined the serotype and antimicrobial susceptibility of 1100 isolates responsible for adult invasive pneumococcal infections (IPD) in Portugal between 2006 and 2008. Serotypes 3 (13%), 1 (12%), 7F (11%), 19A (10%) and 14 (7%) were the most frequent causes of IPD and the two later serotypes accounted for the majority of erythromycin and penicillin nonsusceptible isolates. Serotype 1 was associated with younger adults whereas serotype 3 was associated with older adults. Despite the availability of the 23-valent polysaccharide vaccine (PPV23) in Portugal since 1996, the proportion of PPV23 preventable IPD remained stable and above 80%. Comparing with previous data from Portugal, we showed a continued decline of the serotypes included in the 7-valent conjugate vaccine (PCV7) in adult IPD and a rise of serotypes included in the 13-valent conjugate vaccine, increasing its potential coverage of adult IPD to 70% in 2008. Penicillin non-susceptibility remained stable (17%) whereas erythromycin resistance (18%) has continued to rise in the post-PCV7 years. PMID:22100892

  6. Transcriptional repression of MMP-1 by p21SNFT and reduced in vitro invasiveness of hepatocarcinoma cells.

    PubMed

    Bower, Kristen E; Fritz, Jamie M; McGuire, Kathleen L

    2004-11-18

    p21SNFT (21 kDa small nuclear factor isolated from T cells) is a human basic leucine zipper transcription factor that can repress AP-1-mediated transcription. We show here that overexpression of p21SNFT in HepG2 cells leads to repression of matrix metalloproteinase-1 by 70-80%. p21SNFT interacted with Jun at the matrix metalloproteinase-1 promoter -88 Ets/AP-1 enhancer element, where Jun is known to activate transcription via interaction with Fos and Ets proteins. When p21SNFT/Jun dimers bound the element in the presence of Ets, DNA was protected differently than when Fos was paired with Jun. The data suggest a difference in overall conformation between p21SNFT-containing and Fos-containing complexes that may be involved in the repression of matrix metalloproteinase-1 by p21SNFT. Overexpression of p21SNFT led to a reduction in invasiveness of HepG2 cells through type I collagen and reconstituted basement membrane, an effect similar to that obtained via direct immunodepletion of matrix metalloproteinase-1. The results indicate that the mechanism of repression of matrix metalloproteinase-1 by p21SNFT may be exploited in inhibiting pathological matrix remodeling during cancer progression in vivo. PMID:15467742

  7. Reduced incidence of invasive pneumococcal disease after introduction of the 13-valent conjugate vaccine in Navarre, Spain, 2001-2013.

    PubMed

    Guevara, Marcela; Ezpeleta, Carmen; Gil-Setas, Alberto; Torroba, Luis; Beristain, Xabier; Aguinaga, Aitziber; García-Irure, José Javier; Navascués, Ana; García-Cenoz, Manuel; Castilla, Jesús

    2014-05-01

    Pneumococcal conjugate vaccines (PCVs) were licensed for use in children and became available for private purchase in Spain in 2001 (PCV7), 2009 (PCV10) and 2010 (PCV13). This study evaluates changes in the incidence of invasive pneumococcal disease (IPD) and the pattern of serotypes isolated in Navarre, Spain, between the period of use of PCV7 (2004-2009) and that of PCV13 (2010-2013). The percentage of children <2 years who received at least one dose of PCV in these periods ranged from 25 to 61% and 61 to 78%, respectively. Between the periods 2004-2009 and 2010-2013 IPD incidence declined by 37%, from 14.9 to 9.4 cases/100,000 inhabitants (p<0.001). In children <5 years it fell by 69% (p<0.001), in persons aged 5-64 years, by 34% (p<0.001), and in those ≥ 65, by 23% (p=0.024). The incidence of cases due to PCV13 serotypes declined by 81% (p<0.001) in children <5 years and by 52% (p<0.001) in the whole population. No significant changes were seen in the distribution of clinical presentations or in disease severity. The incidence of IPD has declined and the pattern of serotypes causing IPD has changed notably in children and moderately in adults following the replacement of PCV7 by PCV13. PMID:24674661

  8. Spironolactone promotes autophagy via inhibiting PI3K/AKT/mTOR signalling pathway and reduce adhesive capacity damage in podocytes under mechanical stress.

    PubMed

    Li, Dong; Lu, Zhenyu; Xu, Zhongwei; Ji, Junya; Zheng, Zhenfeng; Lin, Shan; Yan, Tiekun

    2016-08-01

    Mechanical stress which would cause deleterious adhesive effects on podocytes is considered a major contributor to the early progress of diabetic nephropathy (DN). Our previous study has shown that spironolactone could ameliorate podocytic adhesive capacity in diabetic rats. Autophagy has been reported to have a protective role against renal injury. The present study investigated the underlying mechanisms by which spironolactone reduced adhesive capacity damage in podocytes under mechanical stress, focusing on the involvement of autophagy. Human conditional immortalized podocytes exposed to mechanical stress were treated with spironolactone, LY294002 or rapamycin for 48 h. The accumulation of LC3 puncta was detected by immunofluorescence staining. Podocyte expression of mineralocorticoid receptor (MR), integrin β1, LC3, Atg5, p85-PI3K, p-Akt, p-mTOR were detected by Western blotting. Podocyte adhesion to collagen type IV was also performed with spectrophotometry. Immunofluorescence staining showed that the normal level of autophagy was reduced in podocytes under mechanical stress. Decreased integrin β1, LC3, Atg5 and abnormal activation of the PI3K/Akt/mTOR pathway were also detected in podocytes under mechanical stress. Spironolactone up-regulated integrin β1, LC3, Atg5 expression, down-regulated p85-PI3K, p-Akt, p-mTOR expression and reduced podocytic adhesive capacity damage. Our data demonstrated that spironolactone inhibited mechanical-stress-induced podocytic adhesive capacity damage through blocking PI3K/Akt/mTOR pathway and restoring autophagy activity. PMID:27129295

  9. Spironolactone promotes autophagy via inhibiting PI3K/AKT/mTOR signalling pathway and reduce adhesive capacity damage in podocytes under mechanical stress

    PubMed Central

    Li, Dong; Lu, Zhenyu; Xu, Zhongwei; Ji, Junya; Zheng, Zhenfeng; Lin, Shan; Yan, Tiekun

    2016-01-01

    Mechanical stress which would cause deleterious adhesive effects on podocytes is considered a major contributor to the early progress of diabetic nephropathy (DN). Our previous study has shown that spironolactone could ameliorate podocytic adhesive capacity in diabetic rats. Autophagy has been reported to have a protective role against renal injury. The present study investigated the underlying mechanisms by which spironolactone reduced adhesive capacity damage in podocytes under mechanical stress, focusing on the involvement of autophagy. Human conditional immortalized podocytes exposed to mechanical stress were treated with spironolactone, LY294002 or rapamycin for 48 h. The accumulation of LC3 puncta was detected by immunofluorescence staining. Podocyte expression of mineralocorticoid receptor (MR), integrin β1, LC3, Atg5, p85-PI3K, p-Akt, p-mTOR were detected by Western blotting. Podocyte adhesion to collagen type IV was also performed with spectrophotometry. Immunofluorescence staining showed that the normal level of autophagy was reduced in podocytes under mechanical stress. Decreased integrin β1, LC3, Atg5 and abnormal activation of the PI3K/Akt/mTOR pathway were also detected in podocytes under mechanical stress. Spironolactone up-regulated integrin β1, LC3, Atg5 expression, down-regulated p85-PI3K, p-Akt, p-mTOR expression and reduced podocytic adhesive capacity damage. Our data demonstrated that spironolactone inhibited mechanical-stress-induced podocytic adhesive capacity damage through blocking PI3K/Akt/mTOR pathway and restoring autophagy activity. PMID:27129295

  10. Fluorine-Doped Tin Oxide Nanocrystal/Reduced Graphene Oxide Composites as Lithium Ion Battery Anode Material with High Capacity and Cycling Stability.

    PubMed

    Xu, Haiping; Shi, Liyi; Wang, Zhuyi; Liu, Jia; Zhu, Jiefang; Zhao, Yin; Zhang, Meihong; Yuan, Shuai

    2015-12-16

    Tin oxide (SnO2) is a kind of anode material with high theoretical capacity. However, the volume expansion and fast capability fading during cycling have prevented its practical application in lithium ion batteries. Herein, we report that the nanocomposite of fluorine-doped tin oxide (FTO) and reduced graphene oxide (RGO) is an ideal anode material with high capacity, high rate capability, and high stability. The FTO conductive nanocrystals were successfully anchored on RGO nanosheets from an FTO nanocrystals colloid and RGO suspension by hydrothermal treatment. As the anode material, the FTO/RGO composite showed high structural stability during the lithiation and delithiation processes. The conductive FTO nanocrystals favor the formation of stable and thin solid electrolyte interface films. Significantly, the FTO/RGO composite retains a discharge capacity as high as 1439 mAhg(-1) after 200 cycles at a current density of 100 mAg(-1). Moreover, its rate capacity displays 1148 mAhg(-1) at a current density of 1000 mAg(-1). PMID:26606370

  11. Overexpression of KiSS-1 reduces colorectal cancer cell invasion by downregulating MMP-9 via blocking PI3K/Akt/NF-κB signal pathway.

    PubMed

    Chen, Shaoqin; Chen, Wei; Zhang, Xiang; Lin, Suyong; Chen, Zhihua

    2016-04-01

    Metastasis of colorectal cancer (CRC) depends critically on MMP-9. KiSS-1 is a human malignant melanoma metastasis-suppressor gene. Thus, the interaction between MMP-9 and KiSS-1 has drawn considerable attention in recent years. In the present study, it was hypothesized that KiSS-1 gene could repress the metastatic potential of colorectal cancer cells by inhibiting the expression of MMP-9. Stable transfection of KiSS-1 specific siRNA and KiSS-1 expression vector in human CRC cell line HCT-116 was achieved by lentivirus infection. Moreover, the cell proliferation, invasiveness, and apoptosis were evaluated by CCK-8 method, transwell experiment, and fluorescence activated cell sorter, respectively. We also investigated the expression of MMP-9, PI3K, Akt, pAKt, and NF-кB subunit p65 using western blotting. KiSS-1 overexpression significantly decreased the cell proliferation and invasiveness of HCT-119 cells, while apoptosis was enhanced. The result of western blotting showed that synthesis of MMP-9, PI3K, p65, and phosphorylation of Akt were significantly blocked by overexpression of KiSS-1. Concatenated treatment of KiSS-1 overexpression vector with PI3K and Akt agonists attenuated the effect of KiSS-1 on the biological activity of CRC cells and also released the expression of MMP-9, PI3K, p65, and phosphorylation of Akt from the influence of overexpression of KiSS-1. Overexpression of KiSS-1 suppressed the invasiveness of CRC cells, and the gene exerted its function by reducing the expression of MMP-9 via blocking of tge PI3K/Akt/NF-κB pathway. PMID:26847533

  12. Anti-angiogenesis therapy and gap junction inhibition reduce MDA-MB-231 breast cancer cell invasion and metastasis in vitro and in vivo

    PubMed Central

    Zibara, Kazem; Awada, Zahraa; Dib, Leila; El-Saghir, Jamal; Al-Ghadban, Sara; Ibrik, Aida; El-Zein, Nabil; El-Sabban, Marwan

    2015-01-01

    Cancer cells secrete VEGF, which plays a key role in their growth, invasion, extravasation and metastasis. Direct cancer cell-endothelial cell interaction, mediated by gap junctions, is of critical importance in the extravasation process. In this study, we evaluated avastin (Av), an anti-VEGF antibody; and oleamide (OL), a gap junction inhibitor, using MDA-MB-231 human breast cancer cells in vitro and a xenograft murine model in vivo. Results showed that Av/OL significantly decreased proliferation, induced cell cycle arrest and decreased migration and invasion of MDA-MB-231 cells in vitro. In addition, Av/OL significantly decreased homo and hetero-cellular communication interaction between MDA-MDA and MDA-endothelial cells, respectively. The expression levels of several factors including VEGF, HIF1α, CXCR4, Cx26, Cx43, and MMP9 were attenuated upon Av/OL treatment in vitro. On the other hand, avastin, but not oleamide, reduced tumor size of NSG mice injected subdermally (s.d.) with MDA-MB-231 cells, which was also associated with increased survival. Furthermore, Av but also OL, separately, significantly increased the survival rate, and reduced pulmonary and hepatic metastatic foci, of intravenously (i.v.) injected mice. Finally, OL reduced MMP9 protein expression levels, better than Av and in comparisons to control, in the lungs of MDA-MB-231 i.v. injected NSG mice. In conclusion, while avastin has anti-angiogenic, anti-tumor and anti-metastatic activities, oleamide has anti-metastatic activity, presumably at the extravasation level, providing further evidence for the role of gap junction intercellular communication (GJIC) in cancer cell extravasation. PMID:26218768

  13. Upregulation of MHC class I in transgenic mice results in reduced force-generating capacity in slow-twitch muscle.

    PubMed

    Salomonsson, Stina; Grundtman, Cecilia; Zhang, Shi-Jin; Lanner, Johanna T; Li, Charles; Katz, Abram; Wedderburn, Lucy R; Nagaraju, Kanneboyina; Lundberg, Ingrid E; Westerblad, Håkan

    2009-05-01

    Expression of major histocompatibility complex (MHC) class I in skeletal muscle fibers is an early and consistent finding in inflammatory myopathies. To test if MHC class I has a primary role in muscle impairment, we used transgenic mice with inducible overexpression of MHC class I in their skeletal muscle cells. Contractile function was studied in isolated extensor digitorum longus (EDL, fast-twitch) and soleus (slow-twitch) muscles. We found that EDL was smaller, whereas soleus muscle was slightly larger. Both muscles generated less absolute force in myopathic compared with control mice; however, when force was expressed per cross-sectional area, only soleus muscle generated less force. Inflammation was markedly increased, but no changes were found in the activities of key mitochondrial and glycogenolytic enzymes in myopathic mice. The induction of MHC class I results in muscle atrophy and an intrinsic decrease in force-generation capacity. These observations may have important implications for our understanding of the pathophysiological processes of muscle weakness seen in inflammatory myopathies. Muscle Nerve, 2008. PMID:19229963

  14. RA-XII inhibits tumour growth and metastasis in breast tumour-bearing mice via reducing cell adhesion and invasion and promoting matrix degradation

    PubMed Central

    Leung, Hoi-Wing; Zhao, Si-Meng; Yue, Grace Gar-Lee; Lee, Julia Kin-Ming; Fung, Kwok-Pui; Leung, Ping-Chung; Tan, Ning-Hua; Lau, Clara Bik-San

    2015-01-01

    Cancer cells acquire invasive ability to degrade and adhere to extracellular matrix (ECM) and migrate to adjacent tissues. This ultimately results metastasis. Hence, the present study investigated the in vitro effects of cyclopeptide glycoside, RA-XII on cell adhesion, invasion, proliferation and matrix degradation, and its underlying mechanism in murine breast tumour cells, 4T1. The effect of RA-XII on tumour growth and metastasis in 4T1-bearing mice was also investigated. Our results showed that RA-XII inhibited tumour cell adhesion to collagen, fibronectin and laminin, RA-XII also reduced the expressions of vascular cell adhesion molecule, intracellular adhesion molecule and integrins, and integrin binding. In addition, RA-XII significantly inhibited breast tumour cell migration via interfering cofilin signaling and chemokine receptors. The activities of matrix metalloproteinase-9 and urokinase-type of plasminogen activator, and the expressions of ECM-associated proteinases were attenuated significantly by RA-XII. Furthermore, RA-XII induced G1 phase arrest and inhibited the expressions of cyclins and cyclin-dependent kinases. RA-XII inhibited the expressions of molecules in PI3K/AKT, NF-kappaB, FAK/pSRC, MAPK and EGFR signaling. RA-XII was also shown to have anti-tumour, anti-angiogenic and anti-metastatic activities in metastatic breast tumour-bearing mice. These findings strongly suggested that RA-XII is a potential anti-metastatic agent for breast cancer. PMID:26592552

  15. Plakoglobin Reduces the in vitro Growth, Migration and Invasion of Ovarian Cancer Cells Expressing N-Cadherin and Mutant p53

    PubMed Central

    Alaee, Mahsa; Danesh, Ghazal; Pasdar, Manijeh

    2016-01-01

    Aberrant expression of cadherins and catenins plays pivotal roles in ovarian cancer development and progression. Plakoglobin (PG, γ-catenin) is a paralog of β-catenin with dual adhesive and signaling functions. While β-catenin has known oncogenic function, PG generally acts as a tumor/metastasis suppressor. We recently showed that PG interacted with p53 and that its growth/metastasis inhibitory function may be mediated by this interaction. Very little is known about the role of PG in ovarian cancer. Here, we investigated the in vitro tumor/metastasis suppressor effects of PG in ovarian cancer cell lines with mutant p53 expression and different cadherin profiles. We showed that the N-cadherin expressing and E-cadherin and PG deficient ES-2 cells were highly migratory and invasive, whereas OV-90 cells that express E-cadherin, PG and very little/no N-cadherin were not. Exogenous expression of PG or E-cadherin or N-cadherin knockdown in ES-2 cells (ES-2-E-cad, ES-2-PG and ES-2-shN-cad) significantly reduced their migration and invasion. Also, PG expression or N-cadherin knockdown significantly decreased ES-2 cells growth. Furthermore, PG interacted with both cadherins and with wild type and mutant p53 in normal ovarian and ES-2-PG cell lines, respectively. PMID:27144941

  16. Tannin-rich pomegranate rind extracts reduce adhesion to and invasion of Caco-2 Cells by Listeria monocytogenes and decrease its expression of virulence genes.

    PubMed

    Xu, Yunfeng; Li, Guanghui; Zhang, Baigang; Wu, Qian; Wang, Xin; Xia, Xiaodong

    2015-01-01

    Pomegranate rind is rich in tannins that have remarkable antimicrobial activities. This study aimed to evaluate the effects of a tannin-rich fraction from pomegranate rind (TFPR) on Listeria monocytogenes virulence gene expression and on the pathogen's interaction with human epithelial cells. Growth curves were monitored to determine the effect of TFPR on L. monocytogenes growth. The 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide and fluorescence staining assays were used to examine the cytotoxicity of TFPR. The effects of TFPR on L. monocytogenes adhesion to and invasion of epithelial cells were investigated using Caco-2 cells. Real-time quantitative PCR analysis was conducted to quantify mRNA levels of three virulence genes in L. monocytogenes. Results showed that a MIC of TFPR against L. monocytogenes was 5 mg/ml in this study. TFPR exhibited cytotoxicity against Caco-2 cells when the concentration was 2.5 mg/ml. Subinhibitory concentrations of TFPR significantly reduced, in a dose-dependent manner, adhesion to and invasion of Caco-2 cells by L. monocytogenes. When L. monocytogenes was grown in the presence of 2.5 mg/ml TFPR, the transcriptional levels of prfA, inlA, and hly decreased by 17-, 34-, and 28-fold, respectively. PMID:25581187

  17. The Procambium Specification Gene Oshox1 Promotes Polar Auxin Transport Capacity and Reduces Its Sensitivity toward Inhibition1

    PubMed Central

    Scarpella, Enrico; Boot, Kees J.M.; Rueb, Saskia; Meijer, Annemarie H.

    2002-01-01

    The auxin-inducible homeobox gene Oshox1 of rice (Oryza sativa) is a positive regulator of procambial cell fate commitment, and its overexpression reduces the sensitivity of polar auxin transport (PAT) to the PAT inhibitor 1-N-naphthylphthalamic acid (NPA). Here, we show that wild-type rice leaves formed under conditions of PAT inhibition display vein hypertrophy, reduced distance between longitudinal veins, and increased distance between transverse veins, providing experimental evidence for a role of PAT in vascular patterning in a monocot species. Furthermore, we show that Oshox1 overexpression confers insensitivity to these PAT inhibitor-induced vascular-patterning defects. Finally, we show that in the absence of any overt phenotypical change, Oshox1 overexpression specifically reduces the affinity of the NPA-binding protein toward NPA and enhances PAT and its sensitivity toward auxin. These results are consistent with the hypothesis that Oshox1 promotes fate commitment of procambial cells by increasing their auxin conductivity properties and stabilizing this state against modulations of PAT by an endogenous NPA-like molecule. PMID:12428000

  18. Reducing Capacity, Chlorogenic Acid Content and Biological Activity in a Collection of Scarlet (Solanum aethiopicum) and Gboma (S. macrocarpon) Eggplants

    PubMed Central

    Plazas, Mariola; Prohens, Jaime; Cuñat, Amparo Noelia; Vilanova, Santiago; Gramazio, Pietro; Herraiz, Francisco Javier; Andújar, Isabel

    2014-01-01

    Scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants are important vegetables in Sub-Saharan Africa. Few studies have been made on these crops regarding the diversity of phenolic content and their biological activity. We have studied the reducing activity, the chlorogenic acid and other phenolic acid contents in a collection of 56 accessions of scarlet eggplant, including the four cultivated groups (Aculeatum, Gilo, Kumba, Shum) and the weedy intermediate S. aethiopicum-S. anguivi types, as well as in eight accessions of gboma eggplant, including the cultivated S. macrocarpon and its wild ancestor, S. dasyphyllum. A sample of the accessions evaluated in this collection has been tested for inhibition of nitric oxide (NO) using macrophage cell cultures. The results show that there is a great diversity in both crops for reducing activity, chlorogenic acid content and chlorogenic acid peak area (% of total phenolic acids). Heritability (H2) for these traits was intermediate to high in both crops. In all samples, chlorogenic acid was the major phenolic acid and accounted for more than 50% of the chromatogram peak area. Considerable differences were found among and within groups for these traits, but the greatest values for total phenolics and chlorogenic acid content were found in S. dasyphyllum. In most groups, reducing activity was positively correlated (with values of up to 0.904 in the Aculeatum group) with chlorogenic acid content. Inhibition of NO was greatest in samples having a high chlorogenic acid content. The results show that both crops are a relevant source of chlorogenic acid and other phenolic acids. The high diversity found also indicates that there are good prospects for breeding new scarlet and gboma eggplant cultivars with improved content in phenolics and bioactive properties. PMID:25264739

  19. Iron deficiency in cyanobacteria causes monomerization of photosystem I trimers and reduces the capacity for state transitions and the effective absorption cross section of photosystem I in vivo.

    PubMed

    Ivanov, Alexander G; Krol, Marianna; Sveshnikov, Dmitry; Selstam, Eva; Sandström, Stefan; Koochek, Maryam; Park, Youn-Il; Vasil'ev, Sergej; Bruce, Doug; Oquist, Gunnar; Huner, Norman P A

    2006-08-01

    The induction of the isiA (CP43') protein in iron-stressed cyanobacteria is accompanied by the formation of a ring of 18 CP43' proteins around the photosystem I (PSI) trimer and is thought to increase the absorption cross section of PSI within the CP43'-PSI supercomplex. In contrast to these in vitro studies, our in vivo measurements failed to demonstrate any increase of the PSI absorption cross section in two strains (Synechococcus sp. PCC 7942 and Synechocystis sp. PCC 6803) of iron-stressed cells. We report that iron-stressed cells exhibited a reduced capacity for state transitions and limited dark reduction of the plastoquinone pool, which accounts for the increase in PSII-related 685 nm chlorophyll fluorescence under iron deficiency. This was accompanied by lower abundance of the NADP-dehydrogenase complex and the PSI-associated subunit PsaL, as well as a reduced amount of phosphatidylglycerol. Nondenaturating polyacrylamide gel electrophoresis separation of the chlorophyll-protein complexes indicated that the monomeric form of PSI is favored over the trimeric form of PSI under iron stress. Thus, we demonstrate that the induction of CP43' does not increase the PSI functional absorption cross section of whole cells in vivo, but rather, induces monomerization of PSI trimers and reduces the capacity for state transitions. We discuss the role of CP43' as an effective energy quencher to photoprotect PSII and PSI under unfavorable environmental conditions in cyanobacteria in vivo. PMID:16798943

  20. Inhibition of PI3K Pathway Reduces Invasiveness and Epithelial-to-Mesenchymal Transition in Squamous Lung Cancer Cell Lines Harboring PIK3CA Gene Alterations.

    PubMed

    Bonelli, Mara A; Cavazzoni, Andrea; Saccani, Francesca; Alfieri, Roberta R; Quaini, Federico; La Monica, Silvia; Galetti, Maricla; Cretella, Daniele; Caffarra, Cristina; Madeddu, Denise; Frati, Caterina; Lagrasta, Costanza Annamaria; Falco, Angela; Rossetti, Pietro; Fumarola, Claudia; Tiseo, Marcello; Petronini, Pier Giorgio; Ardizzoni, Andrea

    2015-08-01

    A prominent role in the pathogenesis of squamous cell carcinoma of the lung (SQCLC) has been attributed to the aberrant activation of the PI3K signaling pathway, due to amplification or mutations of the p110α subunit of class I phosphatidylinositol 3-kinase (PIK3CA) gene. The aim of our study was to determine whether different genetic alterations of PIK3CA affect the biologic properties of SQCLC and to evaluate the response to specific targeting agents in vitro and in vivo. The effects of NVP-BEZ235, NVP-BKM120, and NVP-BYL719 on two-dimensional/three-dimensional (2D/3D) cellular growth, epithelial-to-mesenchymal transition, and invasiveness were evaluated in E545K or H1047R PIK3CA-mutated SQCLC cells and in newly generated clones carrying PIK3CA alterations, as well as in a xenograft model. PIK3CA mutated/amplified cells showed increased growth rate and enhanced migration and invasiveness, associated with an increased activity of RhoA family proteins and the acquisition of a mesenchymal phenotype. PI3K inhibitors reverted this aggressive phenotype by reducing metalloproteinase production, RhoA activity, and the expression of mesenchymal markers, with the specific PI3K inhibitors NVP-BKM120 and NVP-BYL719 being more effective than the dual PI3K/mTOR inhibitor NVP-BEZ235. A xenograft model of SQCLC confirmed that PIK3CA mutation promotes the acquisition of a mesenchymal phenotype in vivo and proved the efficacy of its specific targeting drug NVP-BYL719 in reducing the growth and the expression of mesenchymal markers in xenotransplanted tumors. These data indicate that PIK3CA mutation/amplification may represent a good predictive feature for the clinical application of specific PI3K inhibitors in SQCLC patients. PMID:26013318

  1. Lung Volume Reduction Surgery and Pulmonary Rehabilitation Improve Exercise Capacity and Reduce Dyspnea During Functional Activities in People with Emphysema

    PubMed Central

    2009-01-01

    Purpose: The purpose of this study was to examine the therapeutic effects of lung volume reduction surgery (LVRS) and pulmonary rehabilitation on levels of dyspnea during functional activities in patients with diffuse emphysema. Methods: Fifteen subjects who had undergone LVRS participated in this study. A visual analog scale (VAS) Activity Dyspnea Scales (VADS) measurement tool developed for this study was determined reliable in 10 subjects. The VADS was used to assess changes in dyspnea with functional activity in 10 subjects prior to and following the interventions of LVRS and pulmonary rehabilitation. Results: Results of this study indicate that LVRS followed by pulmonary rehabilitation significantly reduces levels of dyspnea during functional activities. Conclusion: The VADS developed for this study is a valid and reliable method of assessing changes in levels of dyspnea during functional activities in the LVRS population. PMID:20467532

  2. Evaluation of in vitro antioxidant capacity and reducing potential of polyherbal drug- Bhāraṅgyādi

    PubMed Central

    Kajaria, Divya Kumari; Gangwar, Mayank; Sharma, Amit Kumar; Tripathi, Yamini Bhusan; Tripathi, Jyoti Shankar; Tiwari, Shrikant

    2012-01-01

    Background: Present work was designed to investigate antioxidant activity of polyherbal formulation in search for new, safe and inexpensive antioxidant. Clerodendrum serratum, Hedychium spicatum and Inula racemosa, were extensively used in ayurvedic medicine and were investigated together in the form of polyherbal compound (Bhāraṅgyādi) for their antioxidant potential. Materials and Methods: Hydroalcoholic extract was prepared from the above samples and was tested for total reducing power and in vitro antioxidant activity by ABTS+ assay, Superoxide anion scavenging activity assay and lipid per-oxidation assay. Result: Reducing power shows dose depended increase in concentration maximum absorption of 0.677 ± 0.017 at 1000 μg/ml compared with standard Quercetin 0.856±0.020. ABTS+ assay shows maximum inhibition of 64.2 ± 0.86 with EC50 675.31 ± 4.24. Superoxide free radical shows maximum scavenging activity of 62.45 ± 1.86 with EC50 774.70 ± 5.45. Anti-lipidperoxidation free radicals scavenge maximum absorption of 67.25± 1.89 with EC50 is 700.08 ± 6.81. Ascorbic acid was used as standard with IC50 value is 4.6 μg/ml. The result suggests polyherbal formulation to be a good potential for antioxidant activity. Oxidative stress results from imbalance between free radical-generation and radical scavenging systems. This will lead to tissue damage and oxidative stress. Conclusion: In conclusion, we strongly suggest that Polyherbal compounds are source of potential antioxidant for radical scavenging. The highly positive correlation of antiradical scavenging activity and total polyphenolic content in Polyherbal compounds indicates that polyphenols are important components which could be used for the free radical scavenging activity. Further study is needed for isolation and characterization of the active moiety responsible for biological activity and to treat in various stress condition. PMID:23929990

  3. The Long-Term Effects of Reduced Competitive Ability on Foraging Success of an Invasive Pest Species.

    PubMed

    Westermann, Fabian Ludwig; Bell, Vaughn Antony; Suckling, David Maxwell; Lester, Philip John

    2016-08-01

    Ant species like Pheidole megacephala (F.), Solenopsis invicta (Buren), and the Argentine ant, Linepithema humile (Mayr), have repeatedly been reported to be strongly associated with honeydew-producing arthropods like aphids, scale insects, and mealybugs, effectively protecting them from biological control agents like parasitoids. Here we report the results of a successful trial using pheromone dispensers to suppress Argentine ant activity over large sections in a commercial vineyard over a period of two months and preventing ant access into and foraging within the vine canopy. We found Argentine ant activity to be significantly reduced in pheromone-treated plots for the duration of the trial period compared with control plots. Our results showed a significant reduction in the numbers of Argentine ant workers recruited to randomly placed food resources within treated plots compared with untreated plots. Furthermore, spatial distribution of Argentine ants alongside transects in untreated plots remained relatively continuous, while increasing sharply beyond the borders of treated plots. Lastly, we measured the body fat content of workers and found a significant reduction in fat among workers from treated plots compared with untreated plots, suggesting an adverse effects on nest fitness. Additionally, we provide an initial assessment of the feasibility of the presented approach. Our results showed that it is possible to control Argentine ant, preventing them access to and foraging within the vine canopy, thereby reducing Argentine ants' access to honeydew. PMID:27329630

  4. A reduced core to skin temperature gradient, not a critical core temperature, affects aerobic capacity in the heat.

    PubMed

    Cuddy, John S; Hailes, Walter S; Ruby, Brent C

    2014-07-01

    in beginning and ending core temperatures or baseline 3-mile run time. This capacity difference appears to result from a magnified core to skin gradient via an environmental temperature advantageous to convective heat loss, and in part from an increased sweat rate. PMID:24956952

  5. Enhancing mitochondrial calcium buffering capacity reduces aggregation of misfolded SOD1 and motor neuron cell death without extending survival in mouse models of inherited amyotrophic lateral sclerosis.

    PubMed

    Parone, Philippe A; Da Cruz, Sandrine; Han, Joo Seok; McAlonis-Downes, Melissa; Vetto, Anne P; Lee, Sandra K; Tseng, Eva; Cleveland, Don W

    2013-03-13

    Mitochondria have been proposed as targets for toxicity in amyotrophic lateral sclerosis (ALS), a progressive, fatal adult-onset neurodegenerative disorder characterized by the selective loss of motor neurons. A decrease in the capacity of spinal cord mitochondria to buffer calcium (Ca(2+)) has been observed in mice expressing ALS-linked mutants of SOD1 that develop motor neuron disease with many of the key pathological hallmarks seen in ALS patients. In mice expressing three different ALS-causing SOD1 mutants, we now test the contribution of the loss of mitochondrial Ca(2+)-buffering capacity to disease mechanism(s) by eliminating ubiquitous expression of cyclophilin D, a critical regulator of Ca(2+)-mediated opening of the mitochondrial permeability transition pore that determines mitochondrial Ca(2+) content. A chronic increase in mitochondrial buffering of Ca(2+) in the absence of cyclophilin D was maintained throughout disease course and was associated with improved mitochondrial ATP synthesis, reduced mitochondrial swelling, and retention of normal morphology. This was accompanied by an attenuation of glial activation, reduction in levels of misfolded SOD1 aggregates in the spinal cord, and a significant suppression of motor neuron death throughout disease. Despite this, muscle denervation, motor axon degeneration, and disease progression and survival were unaffected, thereby eliminating mutant SOD1-mediated loss of mitochondrial Ca(2+) buffering capacity, altered mitochondrial morphology, motor neuron death, and misfolded SOD1 aggregates, as primary contributors to disease mechanism for fatal paralysis in these models of familial ALS. PMID:23486940

  6. Reduced graphene oxide/carbon nanotubes sponge: A new high capacity and long life anode material for sodium-ion batteries

    NASA Astrophysics Data System (ADS)

    Yan, Dong; Xu, Xingtao; Lu, Ting; Hu, Bingwen; Chua, Daniel H. C.; Pan, Likun

    2016-06-01

    Reduced graphene oxide/carbon nanotubes (CNTs) sponge (GCNTS) is fabricated via a simple freeze drying of graphene oxide/CNTs mixed solution and subsequent thermal treatment in nitrogen atmosphere, and used as anodes for sodium-ion batteries (SIBs) for the first time. The morphology, structure and electrochemical performance of GCNTS are characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, nitrogen adsorption-desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The results show that GCNTS with 20 wt % CNTs has a highest charge capacity of 436 mA h g-1 after 100 cycles at a current density of 50 mA g-1 and even at a high current density of 10 A g-1, a capacity of 195 mA h g-1 is maintained after 7440 cycles. The high capacity, excellent rate performance and long life cycling enable the GCNTS to be a promising candidate for practical SIBs.

  7. Reduced graphene oxide/carbon nanotubes sponge: A new high capacity and long life anode material for sodium-ion batteries

    NASA Astrophysics Data System (ADS)

    Yan, Dong; Xu, Xingtao; Lu, Ting; Hu, Bingwen; Chua, Daniel H. C.; Pan, Likun

    2016-06-01

    Reduced graphene oxide/carbon nanotubes (CNTs) sponge (GCNTS) is fabricated via a simple freeze drying of graphene oxide/CNTs mixed solution and subsequent thermal treatment in nitrogen atmosphere, and used as anodes for sodium-ion batteries (SIBs) for the first time. The morphology, structure and electrochemical performance of GCNTS are characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, nitrogen adsorption-desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The results show that GCNTS with 20 wt % CNTs has a highest charge capacity of 436 mA h g-1 after 100 cycles at a current density of 50 mA g-1 and even at a high current density of 10 A g-1, a capacity of 195 mA h g-1 is maintained after 7440 cycles. The high capacity, excellent rate performance and long life cycling enable the GCNTS to be a promising candidate for practical SIBs.

  8. Superiority of Minimally Invasive Oesophagectomy in Reducing In-Hospital Mortality of Patients with Resectable Oesophageal Cancer: A Meta-Analysis

    PubMed Central

    Zhou, Can; Zhang, Li; Wang, Hua; Ma, Xiaoxia; Shi, Bohui; Chen, Wuke; He, Jianjun; Wang, Ke; Liu, Peijun; Ren, Yu

    2015-01-01

    Background Compared with open oesophagectomy (OE), minimally invasive oesophagectomy (MIO) proves to have benefits in reducing the risk of pulmonary complications for patients with resectable oesophageal cancer. However, it is unknown whether MIO has superiority in reducing the occurrence of in-hospital mortality (IHM). Objective The objective of this meta-analysis was to explore the effect of MIO vs. OE on the occurrence of in-hospital mortality (IHM). Data Sources Sources such as Medline (through December 31, 2014), Embase (through December 31, 2014), Wiley Online Library (through December 31, 2014), and the Cochrane Library (through December 31, 2014) were searched. Study Selection Data of randomized and non-randomized clinical trials related to MIO versus OE were included. Interventions Eligible studies were those that reported patients who underwent MIO procedure. The control group included patients undergoing conventional OE. Study Appraisal and Synthesis Methods Fixed or random -effects models were used to calculate summary odds ratios (ORs) or relative risks (RRs) for quantification of associations. Heterogeneity among studies was evaluated by using Cochran’s Q and I2 statistics. Results A total of 48 studies involving 14,311 cases of resectable oesophageal cancer were included in the meta-analysis. Compared to patients undergoing OE, patients undergoing MIO had statistically reduced occurrence of IHM (OR=0.69, 95%CI =0.55 -0.86). Patients undergoing MIO also had significantly reduced incidence of pulmonary complications (PCs) (RR=0.73, 95%CI = 0.63-0.86), pulmonary embolism (PE) (OR=0.71, 95%CI= 0.51-0.99) and arrhythmia (OR=0.79, 95%CI = 0.68-0.92). Non-significant reductions were observed among the included studies in the occurrence of anastomotic leak (AL) (OR=0.93, 95%CI =0.78-1.11), or Gastric Tip Necrosis (GTN) (OR=0.89, 95%CI =0.54-1.49). Limitation Most of the included studies were non-randomized case-control studies, with a diversity of study

  9. Reduced cardiolipin content decreases respiratory chain capacities and increases ATP synthesis yield in the human HepaRG cells.

    PubMed

    Peyta, Laure; Jarnouen, Kathleen; Pinault, Michelle; Guimaraes, Cyrille; Pais de Barros, Jean-Paul; Chevalier, Stephan; Dumas, Jean-François; Maillot, François; Hatch, Grant M; Loyer, Pascal; Servais, Stephane

    2016-04-01

    Cardiolipin (CL) is a unique mitochondrial phospholipid potentially affecting many aspects of mitochondrial function/processes, i.e. energy production through oxidative phosphorylation. Most data focusing on implication of CL content and mitochondrial bioenergetics were performed in yeast or in cellular models of Barth syndrome. Previous work reported that increase in CL content leads to decrease in liver mitochondrial ATP synthesis yield. Therefore the aim of this study was to determine the effects of moderate decrease in CL content on mitochondrial bioenergetics in human hepatocytes. For this purpose, we generated a cardiolipin synthase knockdown (shCLS) in HepaRG hepatoma cells showing bioenergetics features similar to primary human hepatocytes. shCLS cells exhibited a 55% reduction in CLS gene and a 40% decrease in protein expression resulting in a 45% lower content in CL compared to control (shCTL) cells. Oxygen consumption was significantly reduced in shCLS cells compared to shCTL regardless of substrate used and energy state analyzed. Mitochondrial low molecular weight supercomplex content was higher in shCLS cells (+60%) compared to shCTL. Significant fragmentation of the mitochondrial network was observed in shCLS cells compared to shCTL cells. Surprisingly, mitochondrial ATP synthesis was unchanged in shCLS compared to shCTL cells but exhibited a higher ATP:O ratio (+46%) in shCLS cells. Our results suggest that lowered respiratory chain activity induced by moderate reduction in CL content may be due to both destabilization of supercomplexes and mitochondrial network fragmentation. In addition, CL content may regulate mitochondrial ATP synthesis yield. PMID:26768115

  10. Adverse effects of reduced oxygen tension on the proliferative capacity of rat kidney and insulin-secreting cell lines involve DNA damage and stress responses

    SciTech Connect

    Chen Jianhua Jones, R. Huw; Tarry-Adkins, Jane; Smith, Noel H.; Ozanne, Susan E.

    2008-10-01

    Standard cell culture conditions do not reflect the physiological environment in terms of oxygen tension (20% vs 3%). The effects of lowering oxygen tension on cell proliferation in culture can be beneficial as well as detrimental depending on the cell line studied, but the molecular mechanism underlying such effects is not fully understood. We observed that the proliferative capacity of the rat cell lines NRK and INS-1 was inhibited when cultured under 3% oxygen as compared to 20% oxygen. Suppression of proliferation in NRK cells was accompanied by induction of DNA double strand breaks whereas in INS-1 cells it was accompanied by up-regulation of p53 and p27. Although Sirt1 was up-regulated in both cell lines by 3% oxygen the effects on antioxidant enzymes (MnSOD, CuZnSOD and catalase) were cell line specific. Marked up-regulation of heme oxygenase-1 (HO-1) was detected in both NRK and INS-1 cells when cultured in 3% oxygen. HO-1 expression can be readily induced by exposure to hydrogen peroxide in culture. These results suggest that reduced oxygen tension suppresses the proliferative capacity of these two cell lines through a stress response that is similar to an oxidative stress response but the molecular events that lead to the reduced cell proliferation are cell line specific.

  11. Adverse effects of reduced oxygen tension on the proliferative capacity of rat kidney and insulin-secreting cell lines involve DNA damage and stress responses

    PubMed Central

    Chen, Jian-Hua; Jones, R. Huw; Tarry-Adkins, Jane; Smith, Noel H.; Ozanne, Susan E.

    2008-01-01

    Standard cell culture conditions do not reflect the physiological environment in terms of oxygen tension (20% vs 3%). The effects of lowering oxygen tension on cell proliferation in culture can be beneficial as well as detrimental depending on the cell line studied, but the molecular mechanism underlying such effects is not fully understood. We observed that the proliferative capacity of the rat cell lines NRK and INS-1 was inhibited when cultured under 3% oxygen as compared to 20% oxygen. Suppression of proliferation in NRK cells was accompanied by induction of DNA double strand breaks whereas in INS-1 cells it was accompanied by up-regulation of p53 and p27. Although Sirt1 was up-regulated in both cell lines by 3% oxygen the effects on antioxidant enzymes (MnSOD, CuZnSOD and catalase) were cell line specific. Marked up-regulation of heme oxygenase-1 (HO-1) was detected in both NRK and INS-1 cells when cultured in 3% oxygen. HO-1 expression can be readily induced by exposure to hydrogen peroxide in culture. These results suggest that reduced oxygen tension suppresses the proliferative capacity of these two cell lines through a stress response that is similar to an oxidative stress response but the molecular events that lead to the reduced cell proliferation are cell line specific. PMID:18692496

  12. PIK3CA gene alterations in bladder cancer are frequent and associate with reduced recurrence in non-muscle invasive tumors.

    PubMed

    Dueñas, Marta; Martínez-Fernández, Mónica; García-Escudero, Ramón; Villacampa, Felipe; Marqués, Miriam; Saiz-Ladera, Cristina; Duarte, José; Martínez, Victor; Gómez, M José; Martín, M Luisa; Fernández, Manoli; Castellano, Daniel; Real, Francisco X; Rodriguez-Peralto, Jose L; De La Rosa, Federico; Paramio, Jesús M

    2015-07-01

    Bladder cancer (BC) is the fifth most common cancer in the world, being the non-muscle invasive tumors (NMIBC) the most frequent. NMIBC shows a very high frequency of recurrence and, in certain cases, tumor progression. The phosphatidylinositol 3-kinase (PI3K) pathway, which controls cell growth, tumorigenesis, cell invasion and drug response, is frequently activated in numerous human cancers, including BC, in part through alterations of PIK3CA gene. However, the significance of PIK3CA gene alterations with respect to clinicopathological characteristics, and in particular tumor recurrence and progression, remains elusive. Here, we analyzed the presence of mutations in FGFR3 and PIK3CA genes and copy number alterations of PIK3CA gene in bladder tumor and their correspondent paired normal samples from 87 patients. We observed an extremely high frequency of PIK3CA gene alterations (mutations, copy gains, or both) in tumor samples, affecting primarily T1 and T2 tumors. A significant number of normal tissues also showed mutations and copy gains, being coincident with those found in the corresponding tumor sample. In low-grade tumors PIK3CA mutations associated with FGFR3 mutations. Alterations in PIK3CA gene resulted in increased Akt activity in tumors. Interestingly, the presence of PIK3CA gene alterations, and in particular gene mutations, is significantly associated with reduced recurrence of NMIBC patients. Importantly, the presence of FGFR3 mutations may influence the clinical outcome of patients bearing alterations in PIK3CA gene, and increased recurrence was associated to FGFR3 mutated, PIK3CA wt tumors. These findings may have high relevance in terms of using PI3K-targeted therapies for BC treatment. PMID:24347284

  13. Long-term non-invasive ventilation reduces readmissions in COPD patients with two or more episodes of acute hypercapnic respiratory failure

    PubMed Central

    Ankjærgaard, Kasper Linde; Maibom, Sophia Liff; Wilcke, Jon Torgny

    2016-01-01

    Background Chronic obstructive pulmonary disease (COPD) patients who have had an episode of acute hypercapnic respiratory failure (AHRF) have a large 1-year risk of death or readmission. Acute non-invasive ventilation (NIV) has been shown to be an effective treatment of AHRF; and long-term NIV (LTNIV) has been shown to be an effective treatment of chronic respiratory failure in stable hypercapnic COPD. We investigated the effects of LTNIV in a group of patients with severe, unstable COPD: frequent admissions and multiple previous episodes of AHRF treated with NIV. Methods We conducted a retrospective analysis of 20 COPD patients treated with LTNIV after two or more episodes of AHRF during 1 year. Results The mean number of AHRF episodes decreased from 2.44 in the year prior to LTNIV initiation to 0.44 in the year following (p<0.0001). The median number of admissions decreased from 5.19 to 1.88 (p=0.0092). Four patients (20%) died in 1 year. LTNIV tended to reduce arterial CO2. No changes were found in lung function. Conclusions LTNIV seems effective in reducing recurrent AHRF and readmissions in a highly select group of patients with severe, unstable COPD and frequent AHRF. PMID:27036658

  14. Ionizing radiation modulates human macrophages towards a pro-inflammatory phenotype preserving their pro-invasive and pro-angiogenic capacities

    PubMed Central

    Teresa Pinto, Ana; Laranjeiro Pinto, Marta; Patrícia Cardoso, Ana; Monteiro, Cátia; Teixeira Pinto, Marta; Filipe Maia, André; Castro, Patrícia; Figueira, Rita; Monteiro, Armanda; Marques, Margarida; Mareel, Marc; dos Santos, Susana Gomes; Seruca, Raquel; Adolfo Barbosa, Mário; Rocha, Sónia; José Oliveira, Maria

    2016-01-01

    In order to improve the efficacy of conventional radiotherapy, attention has been paid to immune cells, which not only modulate cancer cell response to therapy but are also highly recruited to tumours after irradiation. Particularly, the effect of ionizing radiation on macrophages, using therapeutically relevant doses, is not well understood. To evaluate how radiotherapy affects macrophage behaviour and macrophage-mediated cancer cell activity, human monocyte derived-macrophages were subjected, for a week, to cumulative ionizing radiation doses, as used during cancer treatment (2 Gy/fraction/day). Irradiated macrophages remained viable and metabolically active, despite DNA damage. NF-kappaB transcription activation and increased Bcl-xL expression evidenced the promotion of pro-survival activity. A significant increase of pro-inflammatory macrophage markers CD80, CD86 and HLA-DR, but not CCR7, TNF and IL1B was observed after 10 Gy cumulative doses, while anti-inflammatory markers CD163, MRC1, VCAN and IL-10 expression decreased, suggesting the modulation towards a more pro-inflammatory phenotype. Moreover, ionizing radiation induced macrophage morphological alterations and increased their phagocytic rate, without affecting matrix metalloproteases (MMP)2 and MMP9 activity. Importantly, irradiated macrophages promoted cancer cell-invasion and cancer cell-induced angiogenesis. Our work highlights macrophage ability to sustain cancer cell activities as a major concern that needs to be addressed to improve radiotherapy efficacy. PMID:26735768

  15. Resource competition in plant invasions: emerging patterns and research needs

    PubMed Central

    Gioria, Margherita; Osborne, Bruce A.

    2014-01-01

    Invasions by alien plants provide a unique opportunity to examine competitive interactions among plants. While resource competition has long been regarded as a major mechanism responsible for successful invasions, given a well-known capacity for many invaders to become dominant and reduce plant diversity in the invaded communities, few studies have measured resource competition directly or have assessed its importance relative to that of other mechanisms, at different stages of an invasion process. Here, we review evidence comparing the competitive ability of invasive species vs. that of co-occurring native plants, along a range of environmental gradients, showing that many invasive species have a superior competitive ability over native species, although invasive congeners are not necessarily competitively superior over native congeners, nor are alien dominants are better competitors than native dominants. We discuss how the outcomes of competition depend on a number of factors, such as the heterogeneous distribution of resources, the stage of the invasion process, as well as phenotypic plasticity and evolutionary adaptation, which may result in increased or decreased competitive ability in both invasive and native species. Competitive advantages of invasive species over natives are often transient and only important at the early stages of an invasion process. It remains unclear how important resource competition is relative to other mechanisms (competition avoidance via phenological differences, niche differentiation in space associated with phylogenetic distance, recruitment and dispersal limitation, indirect competition, and allelopathy). Finally, we identify the conceptual and methodological issues characterizing competition studies in plant invasions, and we discuss future research needs, including examination of resource competition dynamics and the impact of global environmental change on competitive interactions between invasive and native species. PMID

  16. Ultrahigh Capacity Due to Multi-Electron Conversion Reaction in Reduced Graphene Oxide-Wrapped MoO2 Porous Nanobelts.

    PubMed

    Tang, Wei; Peng, Cheng Xin; Nai, Chang Tai; Su, Jie; Liu, Yan Peng; Reddy, M V Venkatashamy; Lin, Ming; Loh, Kian Ping

    2015-05-01

    Multivalent transition metal oxides (MOx ) containing redox centers which can theoretically accept more than one electron have been suggested as promising anode materials for high-performance lithium ion batteries (LIBs). The Li-storage mechanism of these oxides is suggested to involve an unusual conversion reaction leading to the formation of metallic nanograins and Li2 O; however, a full-scale conversion reaction is seldom observed in molybdenum dioxide (MoO2 ) at room temperature due to slow kinetics. Herein, a full-scale multi-electron conversion reaction, leading to a high reversible capacity (974 mA h g(-1) charging capacity at 60 mA g(-1) ) in LIBs, is realized in a hybrid consisting of reduced graphene oxide (rGO) sheet-wrapped MoO2 porous nanobelts (rGO/MoO2 NBs). The rGO wrapping layers stabilize the nanophase transition in MoO2 and alleviate volume swing effects during lithiation/delithiation processes. This enables the hybrid to exhibit great cycle stability (tested to around 1900 cycles) and ultrafast rate capability (tested up to 50 A g(-1) ). PMID:25620728

  17. Ciguatoxin reduces regenerative capacity of axotomized peripheral neurons and delays functional recovery in pre-exposed mice after peripheral nerve injury

    PubMed Central

    Au, Ngan Pan Bennett; Kumar, Gajendra; Asthana, Pallavi; Tin, Chung; Mak, Yim Ling; Chan, Leo Lai; Lam, Paul Kwan Sing; Ma, Chi Him Eddie

    2016-01-01

    Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury. PMID:27229176

  18. Ciguatoxin reduces regenerative capacity of axotomized peripheral neurons and delays functional recovery in pre-exposed mice after peripheral nerve injury.

    PubMed

    Au, Ngan Pan Bennett; Kumar, Gajendra; Asthana, Pallavi; Tin, Chung; Mak, Yim Ling; Chan, Leo Lai; Lam, Paul Kwan Sing; Ma, Chi Him Eddie

    2016-01-01

    Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury. PMID:27229176

  19. Combining Natural Attenuation Capacity and use of Targeted Technological Mitigation Measures for Reducing Diffuse Nutrient Emissions to Surface Waters: The Danish Way

    NASA Astrophysics Data System (ADS)

    Kronvang, B.; Højberg, A. L.; Hoffmann, C. C.; Windolf, J.; Blicher-Mathiesen, G.

    2015-12-01

    Excess nitrogen (N) and phosphorus (P) emissions to surface waters are a high priority environmental problem worldwide for protection of water resources in times of population growth and climate change. As clean water is a scarce resource the struggle for reducing nutrient emissions are an ongoing issue for many countries and regions. Since the mid1980s a wide range of national regulatory general measures have been implemented to reduce land based nitrogen (N) and phosphorus (P) loadings of the Danish aquatic environment. These measures have addressed both point source emissions and emissions from diffuse sources especially from agricultural production. Following nearly 4 decades of combating nutrient pollution our surface waters such as lakes and estuaries are only slowly responding on the 50% reduction in N and 56% reduction in P. Therefore, the implementation of the EU Water Framework Directive in Danish surface waters still call for further reductions of N and P loadings. Therefore, a new era of targeted implemented measures was the outcome of a Commission on Nature and Agriculture established by the Danish Government in 2013. Their White Book points to the need of increased growth and better environment through more targeted and efficient regulation using advanced technological mitigation methods that are implemented intelligently according to the local natural attenuation capacity for nutrients in the landscape. As a follow up a national consensus model for N was established chaining existing leaching, 3D groundwater and surface water models that enable a calculation of the N dynamics and attenuation capacity within a scale of 15 km2. Moreover, several research projects have been conducted to investigate the effect of a suite of targeted mitigation measures such as restored natural wetlands, constructed wetlands, controlled drainage, buffer strips and constructed buffer strips. The results of these studies will be shared in this presentation.

  20. Investigating Invasives

    ERIC Educational Resources Information Center

    Lightbody, Mary

    2008-01-01

    Invasive species, commonly known as "invasives," are nonnative plants, animals, and microbes that completely take over and change an established ecosystem. The consequences of invasives' spread are significant. In fact, many of the species that appear on the Endangered Species list are threatened by invasives. Therefore, the topic of invasive…

  1. "I Still Haven't Found What I'm Looking For": Parental Privacy Invasion Predicts Reduced Parental Knowledge

    ERIC Educational Resources Information Center

    Hawk, Skyler T.; Keijsers, Loes; Frijns, Tom; Hale, William W., III; Branje, Susan; Meeus, Wim

    2013-01-01

    This 3-year, multi-informant study examined whether youths' perceptions of parental privacy invasion predicted lower parental knowledge over time, as a function of increased adolescent secrecy. Participants were 497 Dutch adolescents (Time 1 M = 13 years, SD = 0.5; 57% boys) and both parents. Higher youth-reported invasion predicted lower…

  2. The small conductance calcium-activated potassium channel 3 (SK3) is a molecular target for Edelfosine to reduce the invasive potential of urothelial carcinoma cells.

    PubMed

    Steinestel, Konrad; Eder, Stefan; Ehinger, Konstantin; Schneider, Juliane; Genze, Felicitas; Winkler, Eva; Wardelmann, Eva; Schrader, Andres J; Steinestel, Julie

    2016-05-01

    Metastasis is the survival-determining factor in urothelial carcinoma (UC) of the urinary bladder. The small conductance calcium-activated potassium channel 3 (SK3) enhances tumor cell invasion in breast cancer and malignant melanoma. Since Edelfosine, a glycerophospholipid with antitumoral properties, effectively inhibits SK3 channel activity, our goal was to evaluate SK3 as a potential molecular target to inhibit the gain of an invasive phenotype in UC. SK3 protein expression was analyzed in 208 tissue samples and UC cell lines. Effects of Edelfosine on SK3 expression and intracellular calcium levels as well as on cell morphology, cell survival and proliferation were assessed using immunoblotting, potentiometric fluorescence microscopy, and clonogenic/cell survival assay; furthermore, we analyzed the effect of Edelfosine and SK3 RNAi knockdown on tumor cell migration and invasion in vitro and in vivo. We found that SK3 is strongly expressed in muscle-invasive UC and in the RT112 cellular tumor model. Higher concentrations of Edelfosine have a strong antitumoral effect on UC cells, while 1 μM effectively inhibits migration/invasion of UC cells in vitro and in vivo comparable to the SK3 knockdown phenotype. Taken together, our results show strong expression of SK3 in muscle-invasive UC, consistent with the postulated role of the protein in tumor cell invasion. Edelfosine is able to effectively inhibit migration and invasion of UC cells in vitro and in vivo in an SK3-dependent way, pointing towards a possible role for Edelfosine as an antiinvasive drug to effectively inhibit UC cell invasion and metastasis. PMID:26619845

  3. Decreased expression of B7-H3 reduces the glycolytic capacity and sensitizes breast cancer cells to AKT/mTOR inhibitors

    PubMed Central

    Nunes-Xavier, Caroline E.; Karlsen, Karine Flem; Tekle, Christina; Pedersen, Cathrine; Øyjord, Tove; Hongisto, Vesa; Nesland, Jahn M.; Tan, Ming; Sahlberg, Kristine Kleivi; Fodstad, Øystein

    2016-01-01

    B7 family proteins are important immune response regulators, and can mediate oncogenic signaling and cancer development. We have used human triple-negative breast cancer cell lines with different expression levels of B7-H3 to evaluate its effects on the sensitivity to 22 different anticancer compounds in a drug screen. API-2 (triciribidine) and everolimus (RAD-001), two inhibitors that target the PI3K/AKT/mTOR pathway, showed enhanced inhibition of cell viability and proliferation in B7-H3 knockdown tumor cells compared to their B7-H3 expressing counterparts. Similar inhibition was seen in control cells treated with an anti-B7-H3 monoclonal antibody. In B7-H3 overexpressing cells, the effects of the two drugs were reduced, supported also by in vivo experiments in which B7-H3 overexpressing xenografts were less sensitive to everolimus than control tumors. In API-2 and everolimus-treated B7-H3 overexpressing cells, phospho-mTOR levels were decreased. However, phosphorylation of p70S6K was differentially regulated in B7-H3 cells treated with API-2 or everolimus, suggesting a different B7-H3-mediated mechanism downstream of mTOR. Both API-2 and everolimus decreased the glycolysis of the cells, whereas knockdown of B7-H3 decreased and B7-H3 overexpression increased the glycolytic capacity. In conclusion, we have unveiled a previously unknown relationship between B7-H3 expression and glycolytic capacity in tumor cells, and found that B7-H3 confers resistance to API-2 and everolimus. The results provide novel insights into the function of B7-H3 in cancer, and suggest that targeting of B7-H3 may be a novel alternative to improve current anticancer therapies. PMID:26771843

  4. Axitinib increases the infiltration of immune cells and reduces the suppressive capacity of monocytic MDSCs in an intracranial mouse melanoma model

    PubMed Central

    Du Four, Stephanie; Maenhout, Sarah K.; De Pierre, Kari; Renmans, Dries; Niclou, Simone P; Thielemans, Kris; Neyns, Bart; Aerts, Joeri L

    2015-01-01

    Melanoma patients are at a high risk of developing brain metastases, which are strongly vascularized and therefore have a significant risk of spontaneous bleeding. VEGF not only plays a role in neo-angiogenesis but also in the antitumor immune response. VEGFR-targeted therapy might not only have an impact on the tumor vascularization but also on tumor-infiltrating immune cells. In this study, we investigated the effect of axitinib, a small molecule TKI of VEGFR-1, -2, and -3, on tumor growth and on the composition of tumor-infiltrating immune cells in subcutaneous and intracranial mouse melanoma models. In vivo treatment with axitinib induced a strong inhibition of tumor growth and significantly improved survival in both tumor models. Characterization of the immune cells within the spleen and tumor of tumor-bearing mice respectively showed a significant increase in the number of CD3+CD8+ T cells and CD11b+ cells of axitinib-treated mice. More specifically, we observed a significant increase of intratumoral monocytic myeloid-derived suppressor cells (moMDSCs; CD11b+Ly6ChighLy6G-). Interestingly, in vitro proliferation assays showed that moMDSCs isolated from spleen or tumor of axitinib-treated mice had a reduced suppressive capacity on a per cell basis as compared to those isolated from vehicle-treated mice. Moreover, MDSCs from axitinib-treated animals displayed the capacity to stimulate allogeneic T cells. Thus, treatment with axitinib induces differentiation of moMDSC toward an antigen-presenting phenotype. Based on these observations, we conclude that the impact of axitinib on tumor growth and survival is most likely not restricted to direct anti-angiogenic effects but also involves important effects on tumor immunity. PMID:26137411

  5. The p.R1819_C1948delinsS mutation makes von Willebrand factor ADAMTS13-resistant and reduces its collagen-binding capacity.

    PubMed

    Daidone, Viviana; Saga, Giorgia; Barbon, Giovanni; Pontara, Elena; Cattini, Maria G; Morpurgo, Margherita; Zanotti, Giuseppe; Casonato, Alessandra

    2015-08-01

    This report concerns abnormal ADAMTS13 (a disintegrin and metalloprotease with a thrombospondin type 1 motif, member 13) and collagen interactions coinciding with the p.R1819_C1948delinsS von Willebrand factor (VWF) mutation associated with the deletion of the C-terminus of the A3 domain (amino acids 1819-1947) in a patient with a history of bleeding. The von Willebrand disease (VWD) phenotype of the patient featured low plasma and platelet VWF, multimers with smears extending over the highest normal oligomers in plasma, but not platelets, and an impaired collagen-binding capacity. In vitro full-length p.R1819_C1948delinsS VWF expression showed impaired VWF release, increased cellular content with normally-multimerized VWF and impaired collagen binding. The recombinant p.R1819_C1948delinsS VWF fragment, extending from domains A2 to B3 (p.R1819_C1948delinsS A2-B3 VWF), was completely resistant to proteolysis by ADAMTS13 in the presence of 1·5 mol/l urea, unlike its normal counterpart. The defect stems from impaired ADAMTS13 binding to p.R1819_C1948delinsS A2-B3, analysed under static conditions. Partial deletion of the C-terminus of the A3 domain thus makes VWF resistant to ADAMTS13, interfering with ADAMTS13 binding to VWF, and impairing the collagen-binding capacity of VWF. The p.R1819_C1948delinsS mutation has both haemorrhagic features (defective collagen binding, reduced VWF levels) and prothrombotic (ADAMTS13 resistance) features, and the latter probably mitigate the patient's bleeding symptoms. PMID:25904363

  6. Reduced Parasite Motility and Micronemal Protein Secretion by a p38 MAPK Inhibitor Leads to a Severe Impairment of Cell Invasion by the Apicomplexan Parasite Eimeria tenella

    PubMed Central

    Bussière, Françoise I.; Le Vern, Yves; Niepceron, Alisson; Silvestre, Anne; de Sablet, Thibaut; Lacroix-Lamandé, Sonia; Laurent, Fabrice

    2015-01-01

    E. tenella infection is associated with a severe intestinal disease leading to high economic losses in poultry industry. Mitogen activated protein kinases (MAPKs) are implicated in early response to infection and are divided in three pathways: p38, extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK). Our objective was to determine the importance of these kinases on cell invasion by E. tenella. We evaluated the effect of specific inhibitors (ERK: PD98059, JNKII: SP600125, p38 MAPK: SB203580) on the invasion of epithelial cells. Incubation of SP600125 and SB203580 with epithelial cells and parasites significantly inhibited cell invasion with the highest degree of inhibition (90%) for SB203580. Silencing of the host p38α MAPK expression by siRNA led to only 20% decrease in cell invasion. In addition, when mammalian epithelial cells were pre-treated with SB203580, and washed prior infection, a 30% decrease in cell invasion was observed. This decrease was overcome when a p38 MAPK activator, anisomycin was added during infection. This suggests an active but limited role of the host p38 MAPK in this process. We next determined whether SB203580 has a direct effect on the parasite. Indeed, parasite motility and secretion of micronemal proteins (EtMIC1, 2, 3 and 5) that are involved in cell invasion were both decreased in the presence of the inhibitor. After chasing the inhibitor, parasite motility and secretion of micronemal proteins were restored and subsequently cell invasion. SB203580 inhibits cell invasion by acting partly on the host cell and mainly on the parasite. PMID:25689363

  7. Reduced parasite motility and micronemal protein secretion by a p38 MAPK inhibitor leads to a severe impairment of cell invasion by the apicomplexan parasite Eimeria tenella.

    PubMed

    Bussière, Françoise I; Brossier, Fabien; Le Vern, Yves; Niepceron, Alisson; Silvestre, Anne; de Sablet, Thibaut; Lacroix-Lamandé, Sonia; Laurent, Fabrice

    2015-01-01

    E. tenella infection is associated with a severe intestinal disease leading to high economic losses in poultry industry. Mitogen activated protein kinases (MAPKs) are implicated in early response to infection and are divided in three pathways: p38, extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK). Our objective was to determine the importance of these kinases on cell invasion by E. tenella. We evaluated the effect of specific inhibitors (ERK: PD98059, JNKII: SP600125, p38 MAPK: SB203580) on the invasion of epithelial cells. Incubation of SP600125 and SB203580 with epithelial cells and parasites significantly inhibited cell invasion with the highest degree of inhibition (90%) for SB203580. Silencing of the host p38α MAPK expression by siRNA led to only 20% decrease in cell invasion. In addition, when mammalian epithelial cells were pre-treated with SB203580, and washed prior infection, a 30% decrease in cell invasion was observed. This decrease was overcome when a p38 MAPK activator, anisomycin was added during infection. This suggests an active but limited role of the host p38 MAPK in this process. We next determined whether SB203580 has a direct effect on the parasite. Indeed, parasite motility and secretion of micronemal proteins (EtMIC1, 2, 3 and 5) that are involved in cell invasion were both decreased in the presence of the inhibitor. After chasing the inhibitor, parasite motility and secretion of micronemal proteins were restored and subsequently cell invasion. SB203580 inhibits cell invasion by acting partly on the host cell and mainly on the parasite. PMID:25689363

  8. Invasive Candidiasis

    MedlinePlus

    ... Invasive candidiasis is an infection caused by a yeast (a type of fungus) called Candida . Unlike Candida ... mouth and throat (also called “thrush”) or vaginal “yeast infections,” invasive candidiasis is a serious infection that ...

  9. Reduced Cardiovascular Capacity and Resting Metabolic Rate in Men with Prostate Cancer Undergoing Androgen Deprivation: A Comprehensive Cross-Sectional Investigation

    PubMed Central

    Wall, Bradley A.; Galvão, Daniel A.; Fatehee, Naeem; Taaffe, Dennis R.; Spry, Nigel; Joseph, David; Newton, Robert U.

    2015-01-01

    Objectives. To investigate if androgen deprivation therapy exposure is associated with additional risk factors for cardiovascular disease and metabolic treatment-related toxicities. Methods. One hundred and seven men (42–89 years) with prostate cancer undergoing androgen deprivation therapy completed a maximal graded objective exercise test to determine maximal oxygen uptake, assessments for resting metabolic rate, body composition, blood pressure and arterial stiffness, and blood biomarker analysis. A cross-sectional analysis was undertaken to investigate the potential impact of therapy exposure with participants stratified into two groups according to duration of androgen deprivation therapy (<3 months and ≥3 months). Results. Maximal oxygen uptake (26.1 ± 6.0 mL/kg/min versus 23.2 ± 5.8 mL/kg/min, p = 0.020) and resting metabolic rate (1795 ± 256 kcal/d versus 1647 ± 236 kcal/d, p = 0.005) were significantly higher in those with shorter exposure to androgen deprivation. There were no differences between groups for peripheral and central blood pressure, arterial stiffness, or metabolic profile. Conclusion. Three months or longer exposure to androgen deprivation therapy was associated with reduced cardiorespiratory capacity and resting metabolic rate, but not in a range of blood biomarkers. These findings suggest that prolonged exposure to androgen deprivation therapy is associated with negative alterations in cardiovascular outcomes. Trial registry is: ACTRN12609000200280. PMID:26587019

  10. An electrochemical sensor for gallic acid based on Fe₂O₃/electro-reduced graphene oxide composite: Estimation for the antioxidant capacity index of wines.

    PubMed

    Gao, Feng; Zheng, Delun; Tanaka, Hidekazu; Zhan, Fengping; Yuan, Xiaoning; Gao, Fei; Wang, Qingxiang

    2015-12-01

    A highly sensitive electrochemical sensor for gallic acid (GA), an important polyphenolic compound, was fabricated using the hybrid material of chitosan (CS), fishbone-shaped Fe2O3 (fFe2O3), and electrochemically reduced graphene oxide (ERGO) as the sensing matrix. The electrochemical characterization experiments showed that the CS-fFe2O3-ERGO modified glassy carbon electrode (CS-fFe2O3-ERGO/GCE) had large surface area, excellent electronic conductivity and high stability. The GA presented a superior electrochemical response on CS-fFe2O3-ERGO/GCE in comparison with the single-component modified electrode. The electrochemical mechanism and optimal test conditions of GA on the electrode surface were carefully investigated. Under the optimal conditions, the oxidation peak currents in differential pulse voltammetry (DPV) experiments exhibited a good linear relationship with the logarithmic values of GA concentration over the range from 1.0×10(-6)M to 1.0×10(-4)M. Based on signal-to-noise (S/N) characteristic of 3, the detection limit was estimated to be 1.5×10(-7)M. The proposed sensor has also been applied for estimating the antioxidant capacity index of real samples of red and white wines. PMID:26354265