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Sample records for affect cellular function

  1. Intermittent hypoxia leads to functional reorganization of mitochondria and affects cellular bioenergetics in marine molluscs.

    PubMed

    Ivanina, Anna V; Nesmelova, Irina; Leamy, Larry; Sokolov, Eugene P; Sokolova, Inna M

    2016-06-01

    Fluctuations in oxygen (O2) concentrations represent a major challenge to aerobic organisms and can be extremely damaging to their mitochondria. Marine intertidal molluscs are well-adapted to frequent O2 fluctuations, yet it remains unknown how their mitochondrial functions are regulated to sustain energy metabolism and prevent cellular damage during hypoxia and reoxygenation (H/R). We used metabolic control analysis to investigate the mechanisms of mitochondrial responses to H/R stress (18 h at <0.1% O2 followed by 1 h of reoxygenation) using hypoxia-tolerant intertidal clams Mercenaria mercenaria and hypoxia-sensitive subtidal scallops Argopecten irradians as models. We also assessed H/R-induced changes in cellular energy balance, oxidative damage and unfolded protein response to determine the potential links between mitochondrial dysfunction and cellular injury. Mitochondrial responses to H/R in scallops strongly resembled those in other hypoxia-sensitive organisms. Exposure to hypoxia followed by reoxygenation led to a strong decrease in the substrate oxidation (SOX) and phosphorylation (PHOS) capacities as well as partial depolarization of mitochondria of scallops. Elevated mRNA expression of a reactive oxygen species-sensitive enzyme aconitase and Lon protease (responsible for degradation of oxidized mitochondrial proteins) during H/R stress was consistent with elevated levels of oxidative stress in mitochondria of scallops. In hypoxia-tolerant clams, mitochondrial SOX capacity was enhanced during hypoxia and continued rising during the first hour of reoxygenation. In both species, the mitochondrial PHOS capacity was suppressed during hypoxia, likely to prevent ATP wastage by the reverse action of FO,F1-ATPase. The PHOS capacity recovered after 1 h of reoxygenation in clams but not in scallops. Compared with scallops, clams showed a greater suppression of energy-consuming processes (such as protein turnover and ion transport) during hypoxia, indicated

  2. Altered lysosomal positioning affects lysosomal functions in a cellular model of Huntington's disease.

    PubMed

    Erie, Christine; Sacino, Matthew; Houle, Lauren; Lu, Michael L; Wei, Jianning

    2015-08-01

    Huntington's disease (HD) is a hereditary and devastating neurodegenerative disorder caused by a mutation in the huntingtin protein. Understanding the functions of normal and mutant huntingtin protein is the key to revealing the pathogenesis of HD and developing therapeutic targets. Huntingtin plays an important role in vesicular and organelle trafficking. Lysosomes are dynamic organelles that integrate several degradative pathways and regulate the activity of mammalian target of rapamycin complex 1 (mTORC1). In the present study, we found that the perinuclear accumulation of lysosomes was increased in a cellular model of HD derived from HD knock-in mice and primary fibroblasts from an HD patient. This perinuclear lysosomal accumulation could be reversed when normal huntingtin was overexpressed in HD cells. When we further investigated the functional significance of the increased perinuclear lysosomal accumulation in HD cells, we demonstrated that basal mTORC1 activity was increased in HD cells. In addition, autophagic influx was also increased in HD cells in response to serum deprivation, which leads to premature fusion of lysosomes with autophagosomes. Taken together, our data suggest that the increased perinuclear accumulation of lysosomes may play an important role in HD pathogenesis by altering lysosomal-dependent functions. PMID:25997742

  3. Reduction of Cellular Expression Levels Is a Common Feature of Functionally Affected Pendrin (SLC26A4) Protein Variants

    PubMed Central

    de Moraes, Vanessa C S; Bernardinelli, Emanuele; Zocal, Nathalia; Fernandez, Jhonathan A; Nofziger, Charity; Castilho, Arthur M; Sartorato, Edi L; Paulmichl, Markus; Dossena, Silvia

    2016-01-01

    Sequence alterations in the pendrin gene (SLC26A4) leading to functionally affected protein variants are frequently involved in the pathogenesis of syndromic and nonsyndromic deafness. Considering the high number of SLC26A4 sequence alterations reported to date, discriminating between functionally affected and unaffected pendrin protein variants is essential in contributing to determine the genetic cause of deafness in a given patient. In addition, identifying molecular features common to the functionally affected protein variants can be extremely useful to design future molecule-directed therapeutic approaches. Here we show the functional and molecular characterization of six previously uncharacterized pendrin protein variants found in a cohort of 58 Brazilian deaf patients. Two variants (p.T193I and p.L445W) were undetectable in the plasma membrane, completely retained in the endoplasmic reticulum and showed no transport function; four (p.P142L, p.G149R, p.C282Y and p.Q413R) showed reduced function and significant, although heterogeneous, expression levels in the plasma membrane. Importantly, total expression levels of all of the functionally affected protein variants were significantly reduced with respect to the wild-type and a fully functional variant (p.R776C), regardless of their subcellular localization. Interestingly, reduction of expression may also reduce the transport activity of variants with an intrinsic gain of function (p.Q413R). As reduction of overall cellular abundance was identified as a common molecular feature of pendrin variants with affected function, the identification of strategies to prevent reduction in expression levels may represent a crucial step of potential future therapeutic interventions aimed at restoring the transport activity of dysfunctional pendrin variants. PMID:26752218

  4. Hox Targets and Cellular Functions

    PubMed Central

    Sánchez-Herrero, Ernesto

    2013-01-01

    Hox genes are a group of genes that specify structures along the anteroposterior axis in bilaterians. Although in many cases they do so by modifying a homologous structure with a different (or no) Hox input, there are also examples of Hox genes constructing new organs with no homology in other regions of the body. Hox genes determine structures though the regulation of targets implementing cellular functions and by coordinating cell behavior. The genetic organization to construct or modify a certain organ involves both a genetic cascade through intermediate transcription factors and a direct regulation of targets carrying out cellular functions. In this review I discuss new data from genome-wide techniques, as well as previous genetic and developmental information, to describe some examples of Hox regulation of different cell functions. I also discuss the organization of genetic cascades leading to the development of new organs, mainly using Drosophila melanogaster as the model to analyze Hox function. PMID:24490109

  5. Do calcium-mediated cellular signalling pathways, prostaglandin E2 (PGE2), estrogen or progesterone receptor antagonists, or bacterial endotoxins affect bovine placental function in vitro?

    PubMed

    Weems, Y S; Randel, R D; Carstens, G E; Welsh, T H; Weems, C W

    2004-04-01

    media treated with RU-486 increased (P < or = 0.05) at 4 and 8 h compared to vehicle controls and was not affected by other treatments (P > or = 0.05). Concentrations of PGE2 in media at 4 and 8 h were lower (P < or = 0.05) when compared to controls except treatment with PGE2 at 4 and 8h and RU-486 at 8h (P > or = 0.05). PGF2alpha was increased (P < or = 0.05) by RU-486 at 8h and no other treatment affected PGF2alpha at 4 or 8 h (P < or = 0.05). In conclusion, modulators of cellular calcium signalling pathways given alone do not affect bovine placental progesterone secretion at the days studied and progesterone receptor-mediated events appear to suppress placental progesterone, PGF2alpha, and PGE2 secretion in cattle. In addition, PGE2 does not appear to regulate bovine placental progesterone secretion when the corpus luteum is functional and bacterial endotoxin does not appear to affect bovine placental secretion of PGF2alpha or PGE2. PMID:15287156

  6. [Photodynamic modulation of cellular functions].

    PubMed

    Li, Yuan; Jiang, Hong-Ning; Cui, Zong-Jie

    2016-08-25

    Photodynamic action, due to the rather limited lifetime (1 μs) and effective reactive distance of singlet oxygen (< 10 nm), could subcellular-specifically regulate different cellular functions. Photodynamic action could activate permanently cholecystokinin (CCK) 1 receptors, and sensitize or desensitize other G protein-coupled receptors. The emergence in recent years of genetically- encoded protein photosensitisers has enabled more precisely-targeted photodynamic modulation of subcellular organelles and functional proteins. Protein photosensitisers (such as KillerRed, miniSOG or SOPP) expressed on the plasma membrane, mitochondria, lysosomes or endoplasmic reticulum can modulate photodynamically subcellular functions and fine-tune protein activity by targeted photooxidation. With the newly emerged active illumination technique, simultaneous photodynamic action localized at multiple sites is now possible, and the contribution of subcellular regions to the whole cell or individual cells to a cell cluster could be quantitated. Photodynamic action with protein photosensitiser will be a powerful tool for nano-manipulation in cell physiology research. PMID:27546513

  7. Cellular Mechanisms Controlling Caspase Activation and Function

    PubMed Central

    Parrish, Amanda B.; Freel, Christopher D.; Kornbluth, Sally

    2013-01-01

    Caspases are the primary drivers of apoptotic cell death, cleaving cellular proteins that are critical for dismantling the dying cell. Initially translated as inactive zymogenic precursors, caspases are activated in response to a variety of cell death stimuli. In addition to factors required for their direct activation (e.g., dimerizing adaptor proteins in the case of initiator caspases that lie at the apex of apoptotic signaling cascades), caspases are regulated by a variety of cellular factors in a myriad of physiological and pathological settings. For example, caspases may be modified posttranslationally (e.g., by phosphorylation or ubiquitylation) or through interaction of modulatory factors with either the zymogenic or active form of a caspase, altering its activation and/or activity. These regulatory events may inhibit or enhance enzymatic activity or may affect activity toward particular cellular substrates. Finally, there is emerging literature to suggest that caspases can participate in a variety of cellular processes unrelated to apoptotic cell death. In these settings, it is particularly important that caspases are maintained under stringent control to avoid inadvertent cell death. It is likely that continued examination of these processes will reveal new mechanisms of caspase regulation with implications well beyond control of apoptotic cell death. PMID:23732469

  8. Shaping cellular form and function by autophagy.

    PubMed

    Bamber, Bruce A; Rowland, Aaron M

    2006-01-01

    In addition to its familiar role in non-selective bulk degradation of cellular material, autophagy can also bring about specific changes in the structure and function of cells. Autophagy has been proposed to operate in a substrate-selective mode to carry out this function, although evidence to demonstrate selectivity has been lacking. A recent study of synapse formation in the nervous system of the nematode Caenorhabditis elegans now provides experimental evidence for substrate-selective autophagy. Synapses form when presynaptic cells contact their postsynaptic partners during development. This contact induces the assembly of synaptically-localized protein complexes in the postsynaptic cell that contain scaffolding proteins and neurotransmitter receptors. When presynaptic contact was blocked, autophagy in the postsynaptic cell was induced. Substrate selectivity was evident in this system: the gamma-aminobutyric acid type A receptor (GABA(A) receptor), an integral-membrane neurotransmitter receptor, trafficked from the cell surface to autophagosomes. By contrast, the acetylcholine receptor, a structurally-similar neurotransmitter receptor, remained on the cell surface. This result provides experimental support for the idea that autophagy can bring about changes in cell structure and behavior by degrading specific cellular proteins, particularly cell surface receptors that are often important for regulating cell growth, differentiation and function. PMID:16874044

  9. Functional and cellular adaptations of rodent skeletal muscle to weightlessness

    NASA Technical Reports Server (NTRS)

    Caiozzo, Vincent J.; Haddad, Fadia; Baker, Michael J.; Baldwin, Kenneth M.

    1995-01-01

    This paper describes the affects of microgravity upon three key cellular levels (functional, protein, and mRNA) that are linked to one another. It is clear that at each of these levels, microgravity produces rapid and substantial alterations. One of the key challenges facing the life science community is the development of effective countermeasures that prevent the loss of muscle function as described in this paper. The development of optimal countermeasures, however, awaits a clearer understanding of events occurring at the levels of transcription, translation, and degradation.

  10. Cellular functions of programmed cell death 5.

    PubMed

    Li, Ge; Ma, Dalong; Chen, Yingyu

    2016-04-01

    Programmed cell death 5 (PDCD5) was originally identified as an apoptosis-accelerating protein that is widely expressed and has been well conserved during the process of evolution. PDCD5 has complex biological functions, including programmed cell death and immune regulation. It can accelerate apoptosis in different type of cells in response to different stimuli. During this process, PDCD5 rapidly translocates from the cytoplasm to the nucleus. PDCD5 regulates the activities of TIP60, HDAC3, MDM2 and TP53 transcription factors. These proteins form part of a signaling network that is disrupted in most, if not all, cancer cells. Recent evidence suggests that PDCD5 participates in immune regulation by promoting regulatory T cell function via the PDCD5-TIP60-FOXP3 pathway. The stability and expression of PDCD5 are finely regulated by other molecules, such as NF-κB p65, OTUD5, YAF2 and DNAJB1. PDCD5 is phosphorylated by CK2 at Ser119, which is required for nuclear translocation in response to genotoxic stress. In this review, we describe what is known about PDCD5 and its cellular functions. PMID:26775586

  11. Myosin VI: cellular functions and motor properties.

    PubMed Central

    Roberts, Rhys; Lister, Ida; Schmitz, Stephan; Walker, Matthew; Veigel, Claudia; Trinick, John; Buss, Folma; Kendrick-Jones, John

    2004-01-01

    Myosin VI has been localized in membrane ruffles at the leading edge of cells, at the trans-Golgi network compartment of the Golgi complex and in clathrin-coated pits or vesicles, indicating that it functions in a wide variety of intracellular processes. Myosin VI moves along actin filaments towards their minus end, which is the opposite direction to all of the other myosins so far studied (to our knowledge), and is therefore thought to have unique properties and functions. To investigate the cellular roles of myosin VI, we identified various myosin VI binding partners and are currently characterizing their interactions within the cell. As an alternative approach, we have expressed and purified full-length myosin VI and studied its in vitro properties. Previous studies assumed that myosin VI was a dimer, but our biochemical, biophysical and electron microscopic studies reveal that myosin VI can exist as a stable monomer. We observed, using an optical tweezers force transducer, that monomeric myosin VI is a non-processive motor which, despite a relatively short lever arm, generates a large working stroke of 18 nm. Whether monomer and/or dimer forms of myosin VI exist in cells and their possible functions will be discussed. PMID:15647169

  12. Short-term exposure to engineered nanomaterials affects cellular epigenome

    PubMed Central

    Lu, Xiaoyan; Miousse, Isabelle R.; Pirela, Sandra V.; Melnyk, Stepan; Koturbash, Igor; Demokritou, Philip

    2015-01-01

    Extensive incorporation of engineered nanomaterials (ENMs) into industrial and biomedical applications increases the risks of exposure to these potentially hazardous materials. While the geno- and cytotoxic effects of ENMs have been investigated, the potential of ENMs to target the cellular epigenome remains largely unknown. Our goal was to determine whether or not industry relevant ENMs can affect the epigenome at low cytotoxic doses. A panel of cells relevant to inhalation exposures such as human and murine macrophages (THP-1 and RAW264.7, respectively) and human small airway epithelial cells (SAEC) were exposed to printer-emitted engineered nanoparticles (PEPs), mild steel welding fumes (MS-WF), copper oxide (CuO), and titanium dioxide (TiO2) nanoparticles. Toxicological effects, including cytotoxicity, oxidative stress, and inflammatory responses were assessed, taking into consideration in-vitro dosimetry. The effects of ENMs on cellular epigenome were determined by addressing the global and transposable elements (TEs)-associated DNA methylation and expression of DNA methylation machinery and TEs. The percentage of ENMs-induced cytotoxicity for all cell lines was in the range of 0-15%. Oxidative stress was evident in SAEC after exposure to PEPs and in THP-1 when exposed to CuO. Additionally, exposure to ENMs resulted in modest alterations in DNA methylation of two most abundant TEs in mammalian genomes, LINE-1 and Alu/SINE, their transcriptional reactivation, and decreased expression of DNA methylation machinery in a cell-, dose-, and ENM-dependent manner. These results indicate that exposure to ENMs at environmentally relevant concentrations, aside from the geno- and cytotoxic effects, can also affect the epigenome of target cells. PMID:25938281

  13. Short-term exposure to engineered nanomaterials affects cellular epigenome.

    PubMed

    Lu, Xiaoyan; Miousse, Isabelle R; Pirela, Sandra V; Melnyk, Stepan; Koturbash, Igor; Demokritou, Philip

    2016-01-01

    Extensive incorporation of engineered nanomaterials (ENMs) into industrial and biomedical applications increases the risks of exposure to these potentially hazardous materials. While the geno- and cytotoxic effects of ENMs have been investigated, the potential of ENMs to target the cellular epigenome remains largely unknown. Our goal was to determine whether industry relevant ENMs can affect the epigenome at low cytotoxic doses. A panel of cells relevant to inhalation exposures such as human and murine macrophages (THP-1 and RAW264.7, respectively) and human small airway epithelial cells (SAEC) were exposed to printer-emitted engineered nanoparticles (PEPs), mild steel welding fumes (MS-WF), copper oxide (CuO) and titanium dioxide nanoparticles. Toxicological effects, including cytotoxicity, oxidative stress and inflammatory responses were assessed, taking into consideration in vitro dosimetry. The effects of ENMs on cellular epigenome were determined by addressing the global and transposable elements (TEs)-associated DNA methylation and expression of DNA methylation machinery and TEs. The percentage of ENMs-induced cytotoxicity for all cell lines was in the range of 0-15%. Oxidative stress was evident in SAEC after exposure to PEPs and in THP-1 when exposed to CuO. In addition, exposure to ENMs resulted in modest alterations in DNA methylation of two most abundant TEs in mammalian genomes, LINE-1 and Alu/SINE, their transcriptional reactivation, and decreased expression of DNA methylation machinery in a cell-, dose- and ENM-dependent manner. These results indicate that exposure to ENMs at environmentally relevant concentrations, aside from the geno- and cytotoxic effects, can also affect the epigenome of target cells. PMID:25938281

  14. Role of XPD in cellular functions: To TFIIH and beyond.

    PubMed

    Houten, Bennett Van; Kuper, Jochen; Kisker, Caroline

    2016-08-01

    XPD, as part of the TFIIH complex, has classically been linked to the damage verification step of nucleotide excision repair (NER). However, recent data indicate that XPD, due to its iron-sulfur center interacts with the iron sulfur cluster assembly proteins, and may interact with other proteins in the cell to mediate a diverse set of biological functions including cell cycle regulation, mitosis, and mitochondrial function. In this perspective, after first reviewing the function and some of the key disease causing variants that affect XPD's interaction with TFIIH and the CDK-activating kinase complex (CAK), we investigate these intriguing cellular roles of XPD and highlight important unanswered questions that provide a fertile ground for further scientific exploration. PMID:27262611

  15. Cellular Functions of Transient Receptor Potential channels

    PubMed Central

    Dadon, Daniela; Minke, Baruch

    2010-01-01

    Transient Receptor Potential channels are polymodal cellular sensors involved in a wide variety of cellular processes, mainly by increasing cellular Ca2+. In this review we focus on the roles of these channels in: i) cell death ii) proliferation and differentiation and iii) synaptic vesicle release. Cell death Ca2+ influx participates in apoptotic and necrotic cell death. The Ca2+ permeability and high sensitivity of part of these channels to oxidative/metabolic stress make them important participants in cell death. Several examples are given. Transient Receptor Potential Melastatin 2 is activated by H2O2, inducing cell death through an increase in cellular Ca2+ and activation of Poly ADP-Ribose Polymerase. Exposure of cultured cortical neurons to oxygen-glucose deprivation, in vitro, causes cell death via cation influx, mediated by Transient Receptor Potential Melastatin 7. Metabolic stress constitutively activates the Ca2+ permeable Transient Receptor Potential channels of Drosophila photoreceptor in the dark, potentially leading to retinal degeneration. Similar sensitivity to metabolic stress characterizes several mammalian Transient Receptor Potential Canonical channels. Proliferation and differentiation The rise in cytosolic Ca2+ induces cell growth, differentiation and proliferation via activation of several transcription factors. Activation a variety of store operated and Transient Receptor Potential channels cause a rise in cytosolic Ca2+, making these channels components involved in proliferation and differentiation. Synaptic vesicle release Transient Receptor Potential Melastatin 7 channels reside in synaptic vesicles and regulate neurotransmitter release by a mechanism that is not entirely clear. All the above features of Transient Receptor Potential channels make them crucial components in important, sometimes conflicting, cellular processes that still need to be explored. PMID:20399884

  16. Cellular cofactors affecting hepatitis C virus infection and replication

    PubMed Central

    Randall, Glenn; Panis, Maryline; Cooper, Jacob D.; Tellinghuisen, Timothy L.; Sukhodolets, Karen E.; Pfeffer, Sebastien; Landthaler, Markus; Landgraf, Pablo; Kan, Sherry; Lindenbach, Brett D.; Chien, Minchen; Weir, David B.; Russo, James J.; Ju, Jingyue; Brownstein, Michael J.; Sheridan, Robert; Sander, Chris; Zavolan, Mihaela; Tuschl, Thomas; Rice, Charles M.

    2007-01-01

    Recently identified hepatitis C virus (HCV) isolates that are infectious in cell culture provide a genetic system to evaluate the significance of virus–host interactions for HCV replication. We have completed a systematic RNAi screen wherein siRNAs were designed that target 62 host genes encoding proteins that physically interact with HCV RNA or proteins or belong to cellular pathways thought to modulate HCV infection. This includes 10 host proteins that we identify in this study to bind HCV NS5A. siRNAs that target 26 of these host genes alter infectious HCV production >3-fold. Included in this set of 26 were siRNAs that target Dicer, a principal component of the RNAi silencing pathway. Contrary to the hypothesis that RNAi is an antiviral pathway in mammals, as has been reported for subgenomic HCV replicons, siRNAs that target Dicer inhibited HCV replication. Furthermore, siRNAs that target several other components of the RNAi pathway also inhibit HCV replication. MicroRNA profiling of human liver, human hepatoma Huh-7.5 cells, and Huh-7.5 cells that harbor replicating HCV demonstrated that miR-122 is the predominant microRNA in each environment. miR-122 has been previously implicated in positively regulating the replication of HCV genotype 1 replicons. We find that 2′-O-methyl antisense oligonucleotide depletion of miR-122 also inhibits HCV genotype 2a replication and infectious virus production. Our data define 26 host genes that modulate HCV infection and indicate that the requirement for functional RNAi for HCV replication is dominant over any antiviral activity this pathway may exert against HCV. PMID:17616579

  17. Cellular and molecular basis of cholinergic function

    SciTech Connect

    Dowdall, M.J.; Hawthorne, J.N.

    1987-01-01

    This book contains 105 selections. Some of the titles are: Functional correlates of brain nicotine receptors; Muscarinic receptor subclasses; Cholinergic innervation and levels of nerve growth factor and its mRNA in the central nervous system; Developmentally regulated neurontrophic activities of Torpedo electric organ tissue; and Association of a regulatory peptide with cholinergic neurons.

  18. Cellular functions of cardiolipin in yeast

    PubMed Central

    Joshi, Amit S.; Zhou, Jingming; Gohil, Vishal M.; Chen, Shuliang; Greenberg, Miriam L.

    2009-01-01

    Summary Cardiolipin (CL), the signature lipid of mitochondria, plays a critical role in mitochondrial function and biogenesis. The availability of yeast mutants blocked in CL synthesis has facilitated studies of the biological role of this lipid. Perturbation of CL synthesis leads to growth defects not only during respiratory growth but also under conditions in which respiration is not essential. CL was shown to play a role in mitochondrial protein import, cell wall biogenesis, aging and apoptosis, ceramide synthesis, and translation of electron transport chain components. The genetic disorder Barth syndrome (BTHS) is caused by mutations in the tafazzin gene resulting in decreased total CL levels, accumulation of monolysocardiolipin (MLCL), and decreased unsaturated fatty acyl species of CL. The variation in clinical presentation of BTHS indicates that other physiological factors play a significant role in modifying the phenotype resulting from tafazzin deficiency. Elucidating the functions of CL is expected to shed light on the role of this important lipid in BTHS and other disorders of mitochondrial dysfunction. PMID:18725250

  19. Microgravity and Cellular Consequences in Lymphocyte Function

    NASA Technical Reports Server (NTRS)

    Pellis, Neal R.; Sundaresan, Alamelu

    2004-01-01

    Mammalian cells adapt to the environment of low gravity and express a series of responses, some possibly from direct effects on cells and others based on environmental conditions created by microgravity. Human lymphocytes in microgravity culture are functionally diminished in activation and locomotion. Both processes are integral to optimal immune response to fight pathogens. The NASA Rotating-wall vessel (RWV) is a well-accepted analog for microgravity culture on the ground. Gene array experiments and immunoblotting identified upstream events in human lymphocytes adapting to microgravity analog culture. Microgravity induces selective changes, many of which are cell membrane related. Results showed that upstream of PKC in the T cell activation cascade, PLC-gamma and LAT are significantly diminished. ZAP 70 which controls LAT activation is also down regulated in modeled microgravity. Thus events governing cell shape might warrant attention in microgravity conditions. The goal of this study is to delineate response suites that are consequential, direct or indirect effects of the microgravity environment and which of these are essential to lymphocytes

  20. Cellular senescence impact on immune cell fate and function.

    PubMed

    Vicente, Rita; Mausset-Bonnefont, Anne-Laure; Jorgensen, Christian; Louis-Plence, Pascale; Brondello, Jean-Marc

    2016-06-01

    Cellular senescence occurs not only in cultured fibroblasts, but also in undifferentiated and specialized cells from various tissues of all ages, in vitro and in vivo. Here, we review recent findings on the role of cellular senescence in immune cell fate decisions in macrophage polarization, natural killer cell phenotype, and following T-lymphocyte activation. We also introduce the involvement of the onset of cellular senescence in some immune responses including T-helper lymphocyte-dependent tissue homeostatic functions and T-regulatory cell-dependent suppressive mechanisms. Altogether, these data propose that cellular senescence plays a wide-reaching role as a homeostatic orchestrator. PMID:26910559

  1. Placebo Sleep Affects Cognitive Functioning

    ERIC Educational Resources Information Center

    Draganich, Christina; Erdal, Kristi

    2014-01-01

    The placebo effect is any outcome that is not attributed to a specific treatment but rather to an individual's mindset (Benson & Friedman, 1996). This phenomenon can extend beyond its typical use in pharmaceutical drugs to involve aspects of everyday life, such as the effect of sleep on cognitive functioning. In 2 studies examining whether…

  2. Computer Modeling of the Earliest Cellular Structures and Functions

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew; Chipot, Christophe; Schweighofer, Karl

    2000-01-01

    In the absence of extinct or extant record of protocells (the earliest ancestors of contemporary cells). the most direct way to test our understanding of the origin of cellular life is to construct laboratory models of protocells. Such efforts are currently underway in the NASA Astrobiology Program. They are accompanied by computational studies aimed at explaining self-organization of simple molecules into ordered structures and developing designs for molecules that perform proto-cellular functions. Many of these functions, such as import of nutrients, capture and storage of energy. and response to changes in the environment are carried out by proteins bound to membrane< We will discuss a series of large-scale, molecular-level computer simulations which demonstrate (a) how small proteins (peptides) organize themselves into ordered structures at water-membrane interfaces and insert into membranes, (b) how these peptides aggregate to form membrane-spanning structures (eg. channels), and (c) by what mechanisms such aggregates perform essential proto-cellular functions, such as proton transport of protons across cell walls, a key step in cellular bioenergetics. The simulations were performed using the molecular dynamics method, in which Newton's equations of motion for each item in the system are solved iteratively. The problems of interest required simulations on multi-nanosecond time scales, which corresponded to 10(exp 6)-10(exp 8) time steps.

  3. Nanotopographical modification: a regulator of cellular function through focal adhesions

    PubMed Central

    Biggs, Manus Jonathan Paul; Richards, R. Geoff; Dalby, Matthew J.

    2010-01-01

    As materials technology and the field of biomedical engineering advances, the role of cellular mechanisms, in particular adhesive interactions with implantable devices, becomes more relevant in both research and clinical practice. A key tenet of medical device design has evolved from the exquisite ability of biological systems to respond to topographical features or chemical stimuli, a process that has led to the development of next-generation biomaterials for a wide variety of clinical disorders. In vitro studies have identified nanoscale features as potent modulators of cellular behavior through the onset of focal adhesion formation. The focus of this review is on the recent developments concerning the role of nanoscale structures on integrin-mediated adhesion and cellular function with an emphasis on the generation of medical constructs with regenerative applications. PMID:20138244

  4. Kinetic Adaptations of Myosins for Their Diverse Cellular Functions.

    PubMed

    Heissler, Sarah M; Sellers, James R

    2016-08-01

    Members of the myosin superfamily are involved in all aspects of eukaryotic life. Their function ranges from the transport of organelles and cargos to the generation of membrane tension, and the contraction of muscle. The diversity of physiological functions is remarkable, given that all enzymatically active myosins follow a conserved mechanoenzymatic cycle in which the hydrolysis of ATP to ADP and inorganic phosphate is coupled to either actin-based transport or tethering of actin to defined cellular compartments. Kinetic capacities and limitations of a myosin are determined by the extent to which actin can accelerate the hydrolysis of ATP and the release of the hydrolysis products and are indispensably linked to its physiological tasks. This review focuses on kinetic competencies that - together with structural adaptations - result in myosins with unique mechanoenzymatic properties targeted to their diverse cellular functions. PMID:26929436

  5. Vesicular stomatitis virus P function depends on cellular growth cycle.

    PubMed

    Stanners, C P; Kennedy, S; Poliquin, L

    1987-09-01

    The P function of vesicular stomatitis virus (VSV) is defined as the viral function which results in a reduced rate of total protein synthesis (viral plus cellular) arising from a nonspecific reduction in the efficiency of the translational machinery in infected cells. The existence of P function has been challenged by Lodish and Porter who were unable to detect it in L-strain mouse cells infected with wild-type VSV (HR) or, as expected, with the P- mutant, T1026-R1. Although other groups have subsequently confirmed the existence of P function and the difference between HR and T1026-R1, we have sought an explanation for the difference between Lodish and Porter's results and those of other laboratories. We show that the VSV P function depends on the phase of the growth cycle of infected L-cell cultures. In very early exponential phase, as used by Lodish and Porter, HR has very little demonstrable P function; as the growth cycle proceeds toward stationary phase, P function becomes more and more manifest. Under the same conditions, T1026-R1 shows no P function throughout the growth cycle. Furthermore we show that the VSV M protein mutant tsG31 has a P++ phenotype reducing total protein synthesis below that seen with wild-type HR. P function can be observed in cells infected with tsG31, even early in the exponential phase of the cellular growth cycle. PMID:2820132

  6. Cellular interactions during tracheary elements formation and function.

    PubMed

    Ménard, Delphine; Pesquet, Edouard

    2015-02-01

    The survival of higher plant species on land depends on the development and function of an efficient vascular system distributing water and minerals absorbed by roots to all aerial organs. This conduction and distribution of plant sap relies on specialized cells named tracheary elements (TEs). In contrast to many other cell types in plants, TEs are functionalized by cell death that hollows the cell protoplast to make way for the sap. To maintain a stable conducting function during plant development, recovery from vascular damages as well as to adapt to environmental changes, TEs are completely dependent on direct cellular interactions with neighboring xylem parenchyma cells (XPs). PMID:25545993

  7. Methods for Determining the Cellular Functions of Vimentin Intermediate Filaments.

    PubMed

    Ridge, Karen M; Shumaker, Dale; Robert, Amélie; Hookway, Caroline; Gelfand, Vladimir I; Janmey, Paul A; Lowery, Jason; Guo, Ming; Weitz, David A; Kuczmarski, Edward; Goldman, Robert D

    2016-01-01

    The type III intermediate filament protein vimentin was once thought to function mainly as a static structural protein in the cytoskeleton of cells of mesenchymal origin. Now, however, vimentin is known to form a dynamic, flexible network that plays an important role in a number of signaling pathways. Here, we describe various methods that have been developed to investigate the cellular functions of the vimentin protein and intermediate filament network, including chemical disruption, photoactivation and photoconversion, biolayer interferometry, soluble bead binding assay, three-dimensional substrate experiments, collagen gel contraction, optical-tweezer active microrheology, and force spectrum microscopy. Using these techniques, the contributions of vimentin to essential cellular processes can be probed in ever further detail. PMID:26795478

  8. Methods for Determining the Cellular Functions of Vimentin Intermediate Filaments

    PubMed Central

    Ridge, Karen M.; Shumaker, Dale; Robert, Amélie; Hookway, Caroline; Gelfand, Vladimir I.; Janmey, Paul A.; Lowery, Jason; Guo, Ming; Weitz, David A.; Kuczmarski, Edward; Goldman, Robert D.

    2016-01-01

    The type III intermediate filament protein vimentin was once thought to function mainly as a static structural protein in the cytoskeleton of cells of mesenchymal origin. Now, however, vimentin is known to form a dynamic, flexible network that plays an important role in a number of signaling pathways. Here, we describe various methods that have been developed to investigate the cellular functions of the vimentin protein and intermediate filament network, including chemical disruption, photoactivation and photoconversion, biolayer interferometry, soluble bead binding assay, three-dimensional substrate experiments, collagen gel contraction, optical-tweezer active microrheology, and force spectrum microscopy. Using these techniques, the contributions of vimentin to essential cellular processes can be probed in ever further detail. PMID:26795478

  9. Intravital FRET: Probing Cellular and Tissue Function in Vivo.

    PubMed

    Radbruch, Helena; Bremer, Daniel; Mothes, Ronja; Günther, Robert; Rinnenthal, Jan Leo; Pohlan, Julian; Ulbricht, Carolin; Hauser, Anja E; Niesner, Raluca

    2015-01-01

    The development of intravital Förster Resonance Energy Transfer (FRET) is required to probe cellular and tissue function in the natural context: the living organism. Only in this way can biomedicine truly comprehend pathogenesis and develop effective therapeutic strategies. Here we demonstrate and discuss the advantages and pitfalls of two strategies to quantify FRET in vivo-ratiometrically and time-resolved by fluorescence lifetime imaging-and show their concrete application in the context of neuroinflammation in adult mice. PMID:26006244

  10. Biology under construction: in vitro reconstitution of cellular function

    PubMed Central

    Liu, Allen P.; Fletcher, Daniel A.

    2010-01-01

    We are much better at taking cells apart than putting them together. Reconstitution of biological processes from component molecules has been a powerful but difficult approach to studying functional organization in biology. Recently, the convergence of biochemical and cell biological advances with new experimental and computational tools is providing the opportunity to reconstitute increasingly complex processes. We predict that this bottom-up strategy will uncover basic processes that guide cellular assembly, advancing both basic and applied sciences. PMID:19672276

  11. The phosphate makes a difference: cellular functions of NADP.

    PubMed

    Agledal, Line; Niere, Marc; Ziegler, Mathias

    2010-01-01

    Recent research has unraveled a number of unexpected functions of the pyridine nucleotides. In this review, we will highlight the variety of known physiological roles of NADP. In its reduced form (NADPH), this molecule represents a universal electron donor, not only to drive biosynthetic pathways. Perhaps even more importantly, NADPH is the unique provider of reducing equivalents to maintain or regenerate the cellular detoxifying and antioxidative defense systems. The roles of NADPH in redox sensing and as substrate for NADPH oxidases to generate reactive oxygen species further extend its scope of functions. NADP(+), on the other hand, has acquired signaling functions. Its conversion to second messengers in calcium signaling may have critical impact on important cellular processes. The generation of NADP by NAD kinases is a key determinant of the cellular NADP concentration. The regulation of these enzymes may, therefore, be critical to feed the diversity of NADP-dependent processes adequately. The increasing recognition of the multiple roles of NADP has thus led to exciting new insights in this expanding field. PMID:20196923

  12. Membrane-Based Functions in the Origin of Cellular Life

    NASA Technical Reports Server (NTRS)

    Chipot, Christophe; New, Michael H.; Schweighofer, Karl; Pohorille, Andrew; Wilson, Michael A.

    1999-01-01

    Our objective is to help explain how the earliest ancestors of contemporary cells (protocells) performed their essential functions employing only the molecules available in the protobiological milieu. Our hypothesis is that vesicles, built of amphiphilic, membrane-forming materials, emerged early in protobiological evolution and served as precursors to protocells. We further assume that the cellular functions associated with contemporary membranes, such as capturing and, transducing of energy, signaling, or sequestering organic molecules and ions, evolved in these membrane environments. An alternative hypothesis is that these functions evolved in different environments and were incorporated into membrane-bound structures at some later stage of evolution. We focus on the application of the fundamental principles of physics and chemistry to determine how they apply to the formation of a primitive, functional cell. Rather than attempting to develop specific models for cellular functions and to identify the origin of the molecules which perform these functions, our goal is to define the structural and energetic conditions that any successful model must fulfill, therefore providing physico-chemical boundaries for these models. We do this by carrying out large-scale, molecular level computer simulations on systems of interest.

  13. Using RNA as Molecular Code for Programming Cellular Function.

    PubMed

    Kushwaha, Manish; Rostain, William; Prakash, Satya; Duncan, John N; Jaramillo, Alfonso

    2016-08-19

    RNA is involved in a wide-range of important molecular processes in the cell, serving diverse functions: regulatory, enzymatic, and structural. Together with its ease and predictability of design, these properties can lead RNA to become a useful handle for biological engineers with which to control the cellular machinery. By modifying the many RNA links in cellular processes, it is possible to reprogram cells toward specific design goals. We propose that RNA can be viewed as a molecular programming language that, together with protein-based execution platforms, can be used to rewrite wide ranging aspects of cellular function. In this review, we catalogue developments in the use of RNA parts, methods, and associated computational models that have contributed to the programmability of biology. We discuss how RNA part repertoires have been combined to build complex genetic circuits, and review recent applications of RNA-based parts and circuitry. We explore the future potential of RNA engineering and posit that RNA programmability is an important resource for firmly establishing an era of rationally designed synthetic biology. PMID:26999422

  14. Computer Modeling of the Earliest Cellular Structures and Functions

    NASA Astrophysics Data System (ADS)

    Pohorille, Andrew

    2000-03-01

    In the absence of extinct or extant record of protocells (the earliest ancestors of contemporary cells), the most direct way to test ourunderstanding of the origin of cellular life is to construct laboratory models of protocells. Such efforts are currently underway in the NASA Astrobiology Program. They are accompanied by computational studies aimed at explaining self-organization of simple molecules into ordered structures and developing designs for molecules that perform protocellular functions. Many of these functions, such as import of nutrients, capture and storage of energy, and response to changes in the environment are carried out by proteins bound to membranes. We will discuss a series of large-scale, molecular-level computer simulations which demonstrate (a) how small proteins (peptides)organize themselves into ordered structures at water-membrane interfaces and insert into membranes, (b) how these peptides aggregate to form membrane-spanning structures (e.g. channels), and (c) by what mechanisms such aggregates perform essential protocellular functions, such as proton transport of protons across cell walls, a key step in cellular bioenergetics. The simulations were performed using the molecular dynamics method, in which Newton's equations of motion for each atom in the system are solved iteratively. The problems of interest required simulations on multi-nanosecond time scales, which corresponded to 10^6-10^8 time steps.

  15. PEG functionalized luminescent lipid particles for cellular imaging

    NASA Astrophysics Data System (ADS)

    Rana, Suman; Barick, K. C.; Shetake, Neena G.; Verma, Gunjan; Aswal, V. K.; Panicker, Lata; Pandey, B. N.; Hassan, P. A.

    2016-08-01

    We report here the synthesis, characterization and cellular uptake of luminescent micelle-like particles with phospholipid core and non-ionic PEG based surfactant polysorbate 80 shell. The adsorption of polysorbate 80 at the interface of lipid containing microemulsion droplets and its solidification upon removal of solvent leads to anchoring of PEG chain to the lipid particles. Hydrophobic partitioning of luminescent molecules, sodium 3-hydroxynaphthalene-2-carboxylic acid to the phospholipid core offers additional functionality to these particles. Thus, the cooperative assembly of lipid, non-ionic amphiphile and organic luminescent probe leads to the formation of multifunctional biocompatible particles which are useful for simultaneous imaging and therapy.

  16. Assemblages: Functional units formed by cellular phase separation

    PubMed Central

    Wright, Peter E.

    2014-01-01

    The partitioning of intracellular space beyond membrane-bound organelles can be achieved with collections of proteins that are multivalent or contain low-complexity, intrinsically disordered regions. These proteins can undergo a physical phase change to form functional granules or other entities within the cytoplasm or nucleoplasm that collectively we term “assemblage.” Intrinsically disordered proteins (IDPs) play an important role in forming a subset of cellular assemblages by promoting phase separation. Recent work points to an involvement of assemblages in disease states, indicating that intrinsic disorder and phase transitions should be considered in the development of therapeutics. PMID:25179628

  17. Neurophysiology of HCN channels: from cellular functions to multiple regulations.

    PubMed

    He, Chao; Chen, Fang; Li, Bo; Hu, Zhian

    2014-01-01

    Hyperpolarization-activated cyclic nucleotide-gated (HCN) cation channels are encoded by HCN1-4 gene family and have four subtypes. These channels are activated upon hyperpolarization of membrane potential and conduct an inward, excitatory current Ih in the nervous system. Ih acts as pacemaker current to initiate rhythmic firing, dampen dendritic excitability and regulate presynaptic neurotransmitter release. This review summarizes recent insights into the cellular functions of Ih and associated behavior such as learning and memory, sleep and arousal. HCN channels are excellent targets of various cellular signals to finely regulate neuronal responses to external stimuli. Numerous mechanisms, including transcriptional control, trafficking, as well as channel assembly and modification, underlie HCN channel regulation. In the next section, we discuss how the intracellular signals, especially recent findings concerning protein kinases and interacting proteins such as cGKII, Ca(2+)/CaMKII and TRIP8b, regulate function and expression of HCN channels, and subsequently provide an overview of the effects of neurotransmitters on HCN channels and their corresponding intracellular mechanisms. We also discuss the dysregulation of HCN channels in pathological conditions. Finally, insight into future directions in this exciting area of ion channel research is provided. PMID:24184323

  18. Integrated Nanoplasmonic Sensing for Cellular Functional Immunoanalysis Using Human Blood

    PubMed Central

    2015-01-01

    Localized surface plasmon resonance (LSPR) nanoplasmonic effects allow for label-free, real-time detection of biomolecule binding events on a nanostructured metallic surface with simple optics and sensing tunability. Despite numerous reports on LSPR bionanosensing in the past, no study thus far has applied the technique for a cytokine secretion assay using clinically relevant immune cells from human blood. Cytokine secretion assays, a technique to quantify intercellular-signaling proteins secreted by blood immune cells, allow determination of the functional response of the donor’s immune cells, thus providing valuable information about the immune status of the donor. However, implementation of LSPR bionanosensing in cellular functional immunoanalysis based on a cytokine secretion assay poses major challenges primarily owing to its limited sensitivity and a lack of sufficient sample handling capability. In this paper, we have developed a label-free LSPR biosensing technique to detect cell-secreted tumor necrosis factor (TNF)-α cytokines in clinical blood samples. Our approach integrates LSPR bionanosensors in an optofluidic platform that permits trapping and stimulation of target immune cells in a microfluidic chamber with optical access for subsequent cytokine detection. The on-chip spatial confinement of the cells is the key to rapidly increasing a cytokine concentration high enough for detection by the LSPR setup, thereby allowing the assay time and sample volume to be significantly reduced. We have successfully applied this approach first to THP-1 cells and then later to CD45 cells isolated directly from human blood. Our LSPR optofluidics device allows for detection of TNF-α secreted from cells as few as 1000, which translates into a nearly 100 times decrease in sample volume than conventional cytokine secretion assay techniques require. We achieved cellular functional immunoanalysis with a minimal blood sample volume (3 μL) and a total assay time 3 times

  19. Electrostatic bio-manipulation for the modification of cellular functions

    NASA Astrophysics Data System (ADS)

    Washizu, Masao

    2013-03-01

    The use of electrostatic field effects, including field-induced reversible-breakdown of the membrane and dielectrophoresis (DEP), in microfabricated structures are investigated. With the use of field constriction created by a micro-orifice whose diameter is smaller than the cells, controlled magnitude of pulsed voltage can be applied across the cell membrane regardless of the cell size, shape or orientation. As a result, the breakdown occurs reproducibly and with minimal invasiveness. The breakdown is used for two purposes, electroporation by which foreign substances can be fed into cells, and electrofusion which creates genetic and/or cytoplasmic mixture among two cells. When GFP plasmid is fed into MSC cell, the gene expression started within 2 hours, and finally observed in more than 50% of cells. For cell fusion, several ten percent fusion yield is achieved for most cell types, with the colony formation in several percents. Timing-controlled feeding foreign substances or mixing cellular contents, with high-yield and low-invasiveness, is expected to bring about a new technology for both genetic and epigenetic modifications of cellular functions, in such field as regenerative medicine.

  20. Rejuvenating cellular respiration for optimizing respiratory function: targeting mitochondria.

    PubMed

    Agrawal, Anurag; Mabalirajan, Ulaganathan

    2016-01-15

    Altered bioenergetics with increased mitochondrial reactive oxygen species production and degradation of epithelial function are key aspects of pathogenesis in asthma and chronic obstructive pulmonary disease (COPD). This motif is not unique to obstructive airway disease, reported in related airway diseases such as bronchopulmonary dysplasia and parenchymal diseases such as pulmonary fibrosis. Similarly, mitochondrial dysfunction in vascular endothelium or skeletal muscles contributes to the development of pulmonary hypertension and systemic manifestations of lung disease. In experimental models of COPD or asthma, the use of mitochondria-targeted antioxidants, such as MitoQ, has substantially improved mitochondrial health and restored respiratory function. Modulation of noncoding RNA or protein regulators of mitochondrial biogenesis, dynamics, or degradation has been found to be effective in models of fibrosis, emphysema, asthma, and pulmonary hypertension. Transfer of healthy mitochondria to epithelial cells has been associated with remarkable therapeutic efficacy in models of acute lung injury and asthma. Together, these form a 3R model--repair, reprogramming, and replacement--for mitochondria-targeted therapies in lung disease. This review highlights the key role of mitochondrial function in lung health and disease, with a focus on asthma and COPD, and provides an overview of mitochondria-targeted strategies for rejuvenating cellular respiration and optimizing respiratory function in lung diseases. PMID:26566906

  1. How mental stress affects endothelial function.

    PubMed

    Toda, Noboru; Nakanishi-Toda, Megumi

    2011-12-01

    Mental stress is an important factor contributing to recognized mechanisms underlying cardiovascular events. Among these, stress-related endothelial dysfunction is an early risk factor that predicts future development of severe cardiovascular disorders. Acute mental stress by a variety of tests impairs endothelial function in humans, although the opposite results have been reported by some investigators. Chronic stress always deteriorates endothelial function in humans and experimental animals. Stress hormones, such as glucocorticoids and pro-inflammatory cytokines, and endothelin-1 liberated in response to mental stress participate in endothelial dysfunction possibly via downregulation of endothelial nitric oxide synthase (eNOS) expression, eNOS inactivation, decreased nitric oxide (NO) actions, and increased NO degradation, together with vasoconstriction counteracting against NO-induced vasodilatation. Catecholamines do not directly affect endothelial function but impair its function when blood pressure elevation by the amines is sustained. Endogenous opioids favorably affect endothelial function, which counteract deteriorating effects of other stress hormones and mediators. Inhibition of cortisol and endothelin-1 production, prevention of pro-inflammatory mediator accumulation, hypnotics, mirthful laughter, humor orientation, and lifestyle modification would contribute to the prevention and treatment for stress-related endothelial dysfunction and future serious cardiovascular disease. PMID:21947555

  2. Alpha-Synuclein Function and Dysfunction on Cellular Membranes

    PubMed Central

    Snead, David

    2014-01-01

    Alpha-synuclein is a small neuronal protein that is closely associated with the etiology of Parkinson's disease. Mutations in and alterations in expression levels of alpha-synuclein cause autosomal dominant early onset heredity forms of Parkinson's disease, and sporadic Parkinson's disease is defined in part by the presence of Lewy bodies and Lewy neurites that are composed primarily of alpha-synuclein deposited in an aggregated amyloid fibril state. The normal function of alpha-synuclein is poorly understood, and the precise mechanisms by which it leads to toxicity and cell death are also unclear. Although alpha-synuclein is a highly soluble, cytoplasmic protein, it binds to a variety of cellular membranes of different properties and compositions. These interactions are considered critical for at least some normal functions of alpha-synuclein, and may well play critical roles in both the aggregation of the protein and its mechanisms of toxicity. Here we review the known features of alpha-synuclein membrane interactions in the context of both the putative functions of the protein and of its pathological roles in disease. PMID:25548530

  3. Natural Products as Tools for Defining How Cellular Metabolism Influences Cellular Immune and Inflammatory Function during Chronic Infection

    PubMed Central

    Lovelace, Erica S.; Polyak, Stephen J.

    2015-01-01

    Chronic viral infections like those caused by hepatitis C virus (HCV) and human immunodeficiency virus (HIV) cause disease that establishes an ongoing state of chronic inflammation. While there have been tremendous improvements towards curing HCV with directly acting antiviral agents (DAA) and keeping HIV viral loads below detection with antiretroviral therapy (ART), there is still a need to control inflammation in these diseases. Recent studies indicate that many natural products like curcumin, resveratrol and silymarin alter cellular metabolism and signal transduction pathways via enzymes such as adenosine monophosphate kinase (AMPK) and mechanistic target of rapamycin (mTOR), and these pathways directly influence cellular inflammatory status (such as NF-κB) and immune function. Natural products represent a vast toolkit to dissect and define how cellular metabolism controls cellular immune and inflammatory function. PMID:26633463

  4. Estrogen treatment affects brain functioning after menopause.

    PubMed

    Bayer, Ulrike; Hausmann, Markus

    2011-12-01

    Sex hormones have powerful neuromodulatory effects on functional brain organization and cognitive functioning. This paper reviews findings from studies investigating the influence of sex hormones in postmenopausal women with and without hormone therapy (HT). Functional brain organization was investigated using different behavioural tasks in postmenopausal women using either estrogen therapy or combined estrogen plus gestagen therapy and age- and IQ-matched postmenopausal women not taking HT. The results revealed HT-related modulations in specific aspects of functional brain organization including functional cerebral asymmetries and interhemispheric interaction. In contrast to younger women during the menstrual cycle, however, it seems that HT, and especially estrogen therapy, after menopause affects intrahemispheric processing rather than interhemispheric interaction. This might be explained by a faster and more pronounced age-related decline in intrahemispheric relative to interhemispheric functioning, which might be associated with higher sensitivity to HT. Taken together, the findings suggest that the female brain retains its plasticity even after reproductive age and remains susceptible to the effects of sex hormones throughout the lifetime, which might help to discover new clinical approaches in the hormonal treatment of neurological and psychiatric disorders. PMID:22120942

  5. Cellular functions of vaults and their involvement in multidrug resistance.

    PubMed

    Steiner, E; Holzmann, K; Elbling, L; Micksche, M; Berger, W

    2006-08-01

    Vaults are evolutionary highly conserved ribonucleoprotein (RNP) particles with a hollow barrel-like structure. They are 41 x 73 nm in size and are composed of multiple copies of three proteins and small untranslated RNA (vRNA). The main component of vaults represents the 110 kDa major vault protein (MVP), whereas the two minor vault proteins comprise the 193 kDa vault poly(ADP-ribose) polymerase (VPARP) and the 240 kDa telomerase-associated protein-1 (TEP1). Vaults are abundantly present in the cytoplasm of eukaryotic cells and they were found to be associated with cytoskeletal elements as well as occasionally with the nuclear envelope. Vaults and MVP have been associated with several cellular processes which are also involved in cancer development like cell motility and differentiation. Due to the over-expression of MVP (also termed lung resistance-related protein or LRP) in several P-glycoprotein (P-gp)-negative chemoresistant cancer cell lines, vaults have been linked to multidrug resistance (MDR). Accordingly, high levels of MVP were found in tissues chronically exposed to xenobiotics. In addition, the expression of MVP correlated with the degree of malignancy in certain cancer types, suggesting a direct involvement in tumor development and/or progression. Based on the finding that MVP binds several phosphatases and kinases including PTEN, SHP-2 as well as Erk, evidence is accumulating that MVP might be involved in the regulation of important cell signalling pathways including the PI3K/Akt and the MAPK pathways. In this review we summarize the current knowledge concerning the vault particle and discuss its possible cellular functions, focusing on the role of vaults in chemotherapy resistance. PMID:16918321

  6. Compact Biocompatible Quantum Dots Functionalized for Cellular Imaging

    PubMed Central

    Liu, Wenhao; Howarth, Mark; Greytak, Andrew B.; Zheng, Yi; Nocera, Daniel G.; Ting, Alice Y.; Bawendi, Moungi G.

    2009-01-01

    We present a family of water-soluble quantum dots (QDs) that exhibit low nonspecific binding to cells, small hydrodynamic diameter, tunable surface charge, high quantum yield, and good solution stability across a wide pH range. These QDs are amenable to covalent modification via simple carbodiimide coupling chemistry, which is achieved by functionalizing the surface of QDs with a new class of heterobifunctional ligands incorporating dihydrolipoic acid, a short poly(ethylene glycol) (PEG) spacer, and an amine or carboxylate terminus. The covalent attachment of molecules is demonstrated by appending a rhodamine dye to form a QD-dye conjugate exhibiting fluorescence resonance energy transfer (FRET). High-affinity labeling is demonstrated by covalent attachment of streptavidin, thus enabling the tracking of biotinylated epidermal growth factor (EGF) bound to EGF receptor on live cells. In addition, QDs solubilized with the heterobifunctional ligands retain their metal-affinity driven conjugation chemistry with polyhistidine-tagged proteins. This dual functionality is demonstrated by simultaneous covalent attachment of a rhodamine FRET acceptor and binding of polyhistidine-tagged streptavidin on the same nanocrystal to create a targeted QD, which exhibits dual-wavelength emission. Such emission properties could serve as the basis for ratiometric sensing of the cellular receptor’s local chemical environment. PMID:18177042

  7. Membrane-Based Functions in the Origin of Cellular Life

    NASA Technical Reports Server (NTRS)

    Wilson, Michael A.

    2003-01-01

    How simple membrane peptides performed such essential proto-cellular functions as transport of ions and organic matter across membranes separating the interior of the cell from the environment, capture and utilization of energy, and transduction of environmental signals, is a key question in protobiological evolution. On the basis of detailed, molecular-level computer simulations we investigate how these peptides insert into membranes, self-assemble into higher-order structures and acquire functions. We have studied the insertion of an a-helical peptide containing leucine (L) and serine (S) of the form (LSLLLSL)S into a model membrane. The transmembrane state is metastable, and approximately 15 kcal/mol is required to insert the peptide into the membrane. Investigations of dimers formed by (LSLLLSL)S and glycophorin A demonstrate how the favorable free energy of helix association can offset the unfavorable free energy of insertion, leading to self- assembly of peptide helices in the membrane. An example of a self-assembled structure is the tetrameric transmembrane pore of the influenza virus M2 protein, which is an efficient and selective voltage-gated proton channel. Our simulations explain the gating mechanism and provide guidelines how to reengineering the channel to act as a simple proton pump. In general, emergence of integral membrane proteins appears to be quite feasible and may be easier to envision than the emergence of water-soluble proteins.

  8. Cellular Functions of NSF: Not Just SNAPs and SNAREs

    PubMed Central

    Zhao, Chunxia; Slevin, John T.; Whiteheart, Sidney W.

    2007-01-01

    NSF is an AAA protein, broadly required for intracellular membrane fusion. NSF functions as a SNARE chaperone which binds, through SNAPs, to SNARE complexes and utilizes the energy of ATP hydrolysis to disassemble them thus facilitating SNARE recycling. While this is a major function of NSF, it does seem to interact with other proteins, such as the AMPA receptor subunit, GluR2, and β2-AR and is thought to affect their trafficking patterns. New data suggest that NSF may be regulated by transient post-translational modifications such as phosphorylation and nitrosylation. These new aspects of NSF function as well as its role in SNARE complex dynamics will be discussed. PMID:17397838

  9. Soil restoration with organic amendments: linking cellular functionality and ecosystem processes

    PubMed Central

    Bastida, F.; Selevsek, N.; Torres, I. F.; Hernández, T.; García, C.

    2015-01-01

    A hot topic in recent decades, the application of organic amendments to arid-degraded soils has been shown to benefit microbially-mediated processes. However, despite the importance of soils for global sustainability, a gap has not been addressed yet in soil science: is there any connection between ecosystem-community processes, cellular functionality, and microbial lifestyles (i.e. oligotrophy-copiotrophy) in restored soils? Together with classical ecosystem indicators (fatty-acids, extracellular-enzyme activities, basal respiration), state-of-the-art metaproteomics was applied to fill this gap in a model-restoration experiment initiated 10-years ago by the addition of sewage-sludge and compost. Organic amendment strongly impacted ecosystem processes. Furthermore, the type of material used induced differences in the cellular functionalities through variations in the percentages of proteins involved in translation, transcription, energy production and C-fixation. We conclude that the long-term impact of organic restoration goes beyond ecosystem processes and affects cellular functionalities and phyla-lifestyles coupled with differences in microbial-community structures. PMID:26503516

  10. Soil restoration with organic amendments: linking cellular functionality and ecosystem processes

    NASA Astrophysics Data System (ADS)

    Bastida, F.; Selevsek, N.; Torres, I. F.; Hernández, T.; García, C.

    2015-10-01

    A hot topic in recent decades, the application of organic amendments to arid-degraded soils has been shown to benefit microbially-mediated processes. However, despite the importance of soils for global sustainability, a gap has not been addressed yet in soil science: is there any connection between ecosystem-community processes, cellular functionality, and microbial lifestyles (i.e. oligotrophy-copiotrophy) in restored soils? Together with classical ecosystem indicators (fatty-acids, extracellular-enzyme activities, basal respiration), state-of-the-art metaproteomics was applied to fill this gap in a model-restoration experiment initiated 10-years ago by the addition of sewage-sludge and compost. Organic amendment strongly impacted ecosystem processes. Furthermore, the type of material used induced differences in the cellular functionalities through variations in the percentages of proteins involved in translation, transcription, energy production and C-fixation. We conclude that the long-term impact of organic restoration goes beyond ecosystem processes and affects cellular functionalities and phyla-lifestyles coupled with differences in microbial-community structures.

  11. Soil restoration with organic amendments: linking cellular functionality and ecosystem processes.

    PubMed

    Bastida, F; Selevsek, N; Torres, I F; Hernández, T; García, C

    2015-01-01

    A hot topic in recent decades, the application of organic amendments to arid-degraded soils has been shown to benefit microbially-mediated processes. However, despite the importance of soils for global sustainability, a gap has not been addressed yet in soil science: is there any connection between ecosystem-community processes, cellular functionality, and microbial lifestyles (i.e. oligotrophy-copiotrophy) in restored soils? Together with classical ecosystem indicators (fatty-acids, extracellular-enzyme activities, basal respiration), state-of-the-art metaproteomics was applied to fill this gap in a model-restoration experiment initiated 10-years ago by the addition of sewage-sludge and compost. Organic amendment strongly impacted ecosystem processes. Furthermore, the type of material used induced differences in the cellular functionalities through variations in the percentages of proteins involved in translation, transcription, energy production and C-fixation. We conclude that the long-term impact of organic restoration goes beyond ecosystem processes and affects cellular functionalities and phyla-lifestyles coupled with differences in microbial-community structures. PMID:26503516

  12. Calibrating floor field cellular automaton models for pedestrian dynamics by using likelihood function optimization

    NASA Astrophysics Data System (ADS)

    Lovreglio, Ruggiero; Ronchi, Enrico; Nilsson, Daniel

    2015-11-01

    The formulation of pedestrian floor field cellular automaton models is generally based on hypothetical assumptions to represent reality. This paper proposes a novel methodology to calibrate these models using experimental trajectories. The methodology is based on likelihood function optimization and allows verifying whether the parameters defining a model statistically affect pedestrian navigation. Moreover, it allows comparing different model specifications or the parameters of the same model estimated using different data collection techniques, e.g. virtual reality experiment, real data, etc. The methodology is here implemented using navigation data collected in a Virtual Reality tunnel evacuation experiment including 96 participants. A trajectory dataset in the proximity of an emergency exit is used to test and compare different metrics, i.e. Euclidean and modified Euclidean distance, for the static floor field. In the present case study, modified Euclidean metrics provide better fitting with the data. A new formulation using random parameters for pedestrian cellular automaton models is also defined and tested.

  13. Cellular function of neuropathy target esterase in lysophosphatidylcholine action

    SciTech Connect

    Vose, Sarah C.; Fujioka, Kazutoshi; Gulevich, Alex G.; Lin, Amy Y.; Holland, Nina T.; Casida, John E.

    2008-11-01

    Neuropathy target esterase (NTE) plays critical roles in embryonic development and maintenance of peripheral axons. It is a secondary target of some organophosphorus toxicants including analogs of insecticides and chemical warfare agents. Although the mechanistic role of NTE in vivo is poorly defined, it is known to hydrolyze lysophosphatidylcholine (LPC) in vitro and may protect cell membranes from cytotoxic accumulation of LPC. To determine the cellular function of NTE, Neuro-2a and COS-7 cells were transfected with a full-length human NTE-containing plasmid yielding recombinant NTE (rNTE). We find the same inhibitor sensitivity and specificity profiles for rNTE assayed with LPC or phenyl valerate (a standard NTE substrate) and that this correlation extends to the LPC hydrolases of human brain, lymphocytes and erythrocytes. All of these LPC hydrolases are therefore very similar to each other in respect to a conserved inhibitor binding site conformation. NTE is expressed in brain and lymphocytes and contributes to LPC hydrolase activities in these tissues. The enzyme or enzymes responsible for erythrocyte LPC hydrolase activity remain to be identified. We also show that rNTE protects Neuro-2a and COS-7 cells from exogenous LPC cytotoxicity. Expression of rNTE in Neuro-2a cells alters their phospholipid balance (analyzed by liquid chromatography-mass spectrometry with single ion monitoring) by lowering LPC-16:0 and LPC-18:0 and elevating glycerophosphocholine without a change in phosphatidylcholine-16:0/18:1 or 16:0/18:2. NTE therefore serves an important function in LPC homeostasis and action.

  14. New structural and functional defects in polyphosphate deficient bacteria: A cellular and proteomic study

    PubMed Central

    2010-01-01

    Background Inorganic polyphosphate (polyP), a polymer of tens or hundreds of phosphate residues linked by ATP-like bonds, is found in all organisms and performs a wide variety of functions. PolyP is synthesized in bacterial cells by the actions of polyphosphate kinases (PPK1 and PPK2) and degraded by exopolyphosphatase (PPX). Bacterial cells with polyP deficiencies due to knocking out the ppk1 gene are affected in many structural and important cellular functions such as motility, quorum sensing, biofilm formation and virulence among others. The cause of this pleiotropy is not entirely understood. Results The overexpression of exopolyphosphatase in bacteria mimicked some pleitropic defects found in ppk1 mutants. By using this approach we found new structural and functional defects in the polyP-accumulating bacteria Pseudomonas sp. B4, which are most likely due to differences in the polyP-removal strategy. Colony morphology phenotype, lipopolysaccharide (LPS) structure changes and cellular division malfunction were observed. Finally, we used comparative proteomics in order to elucidate the cellular adjustments that occurred during polyP deficiency in this bacterium and found some clues that helped to understand the structural and functional defects observed. Conclusions The results obtained suggest that during polyP deficiency energy metabolism and particularly nucleoside triphosphate (NTP) formation were affected and that bacterial cells overcame this problem by increasing the flux of energy-generating metabolic pathways such as tricarboxilic acid (TCA) cycle, β-oxidation and oxidative phosphorylation and by reducing energy-consuming ones such as active transporters and amino acid biosynthesis. Furthermore, our results suggest that a general stress response also took place in the cell during polyP deficiency. PMID:20067623

  15. Can lifestyle modification affect men's erectile function?

    PubMed

    Hehemann, Marah C; Kashanian, James A

    2016-04-01

    Erectile dysfunction (ED) is a common condition affecting millions of men worldwide. The pathophysiology and epidemiologic links between ED and risk factors for cardiovascular disease (CVD) are well-established. Lifestyle modifications such as smoking cessation, weight reduction, dietary modification, physical activity, and psychological stress reduction have been increasingly recognized as foundational to the prevention and treatment of ED. The aim of this review is to outline behavioral choices which may increase ones risk of developing ED, to present relevant studies addressing lifestyle factors correlated with ED, and to highlight proposed mechanisms for intervention aimed at improving erectile function in men with ED. These recommendations can provide a framework for counseling patients with ED about lifestyle modification. PMID:27141445

  16. Contaminant loading in remote Arctic lakes affects cellular stress-related proteins expression in feral charr.

    USGS Publications Warehouse

    Wiseman, Steve; Jorgensen, Even H.; Maule, Alec G.; Vijayan, Mathilakath M.

    2011-01-01

    The remote Arctic lakes on Bjornoya Island, Norway, offer a unique opportunity to study possible affect of lifelong contaminant exposure in wild populations of landlocked Arctic charr (Salvelinus alpinus). This is because Lake Ellasjoen has persistent organic pollutant (POP) levels that are significantly greater than in the nearby Lake Oyangen. We examined whether this differential contaminant loading was reflected in the expression of protein markers of exposure and effect in the native fish. We assessed the expressions of cellular stress markers, including cytochrome P4501A (Cyp1A), heat shock protein 70 (hsp70), and glucocorticoid receptor (GR) in feral charr from the two lakes. The average polychlorinated biphenyl (PCB) load in the charr liver from Ellasjoen was approximately 25-fold higher than in individuals from Oyangen. Liver Cyp1A protein expression was significantly higher in individuals from Ellasjoen compared with Oyangen, confirming differential PCB exposure. There was no significant difference in hsp70 protein expression in charr liver between the two lakes. However, brain hsp70 protein expression was significantly elevated in charr from Ellasjoen compared with Oyangen. Also, liver GR protein expression was significantly higher in the Ellasjoen charr compared with Oyangen charr. Taken together, our results suggest changes to cellular stress-related protein expression as a possible adaptation to chronic-contaminant exposure in feral charr in the Norwegian high-Arctic.

  17. In situ CUTANEOUS CELLULAR IMMUNE RESPONSE IN DOGS NATURALLY AFFECTED BY VISCERAL LEISHMANIASIS

    PubMed Central

    ROSSI, Claudio Nazaretian; TOMOKANE, Thaise Yumie; BATISTA, Luis Fábio da Silva; MARCONDES, Mary; LARSSON, Carlos Eduardo; LAURENTI, Márcia Dalastra

    2016-01-01

    SUMMARY Thirty-eight dogs naturally affected by visceral leishmaniasis were recruited in Araçatuba, São Paulo State, Brazil - an endemic area for visceral leishmaniasis. The animals were distributed into one of two groups, according to their clinical and laboratory features, as either symptomatic or asymptomatic dogs. Correlations between clinical features and inflammatory patterns, cellular immune responses, and parasitism in the macroscopically uninjured skin of the ear were investigated. Histological skin patterns were similar in both groups, and were generally characterized by a mild to intense inflammatory infiltrate in the dermis, mainly consisting of mononuclear cells. There was no difference in the number of parasites in the skin (amastigotes/mm²) between the two groups. Concerning the characterization of the cellular immune response, the number of positive inducible nitric oxide synthase (iNOS+) cells was higher in the dermis of symptomatic than in asymptomatic dogs (p = 0.0368). A positive correlation between parasite density and macrophages density (p = 0.031), CD4+ T-cells (p = 0.015), and CD8+ T-cells (p = 0.023) was observed. Furthermore, a positive correlation between density of iNOS+ cells and CD3+ T-cells (p = 0.005), CD4+ T-cells (p = 0.001), and CD8+ T-cells (p = 0.0001) was also found. The results showed the existence of a non-specific chronic inflammatory infiltrate in the dermis of dogs affected by visceral leishmaniasis, characterized by the presence of activated macrophages and T-lymphocytes, associated to cutaneous parasitism, independent of clinical status. PMID:27410908

  18. In situ CUTANEOUS CELLULAR IMMUNE RESPONSE IN DOGS NATURALLY AFFECTED BY VISCERAL LEISHMANIASIS.

    PubMed

    Rossi, Claudio Nazaretian; Tomokane, Thaise Yumie; Batista, Luis Fábio da Silva; Marcondes, Mary; Larsson, Carlos Eduardo; Laurenti, Márcia Dalastra

    2016-07-11

    Thirty-eight dogs naturally affected by visceral leishmaniasis were recruited in Araçatuba, São Paulo State, Brazil - an endemic area for visceral leishmaniasis. The animals were distributed into one of two groups, according to their clinical and laboratory features, as either symptomatic or asymptomatic dogs. Correlations between clinical features and inflammatory patterns, cellular immune responses, and parasitism in the macroscopically uninjured skin of the ear were investigated. Histological skin patterns were similar in both groups, and were generally characterized by a mild to intense inflammatory infiltrate in the dermis, mainly consisting of mononuclear cells. There was no difference in the number of parasites in the skin (amastigotes/mm²) between the two groups. Concerning the characterization of the cellular immune response, the number of positive inducible nitric oxide synthase (iNOS+) cells was higher in the dermis of symptomatic than in asymptomatic dogs (p = 0.0368). A positive correlation between parasite density and macrophages density (p = 0.031), CD4+ T-cells (p = 0.015), and CD8+ T-cells (p = 0.023) was observed. Furthermore, a positive correlation between density of iNOS+ cells and CD3+ T-cells (p = 0.005), CD4+ T-cells (p = 0.001), and CD8+ T-cells (p = 0.0001) was also found. The results showed the existence of a non-specific chronic inflammatory infiltrate in the dermis of dogs affected by visceral leishmaniasis, characterized by the presence of activated macrophages and T-lymphocytes, associated to cutaneous parasitism, independent of clinical status. PMID:27410908

  19. Hyperinsulinemia adversely affects lung structure and function.

    PubMed

    Singh, Suchita; Bodas, Manish; Bhatraju, Naveen K; Pattnaik, Bijay; Gheware, Atish; Parameswaran, Praveen Kolumam; Thompson, Michael; Freeman, Michelle; Mabalirajan, Ulaganathan; Gosens, Reinoud; Ghosh, Balaram; Pabelick, Christina; Linneberg, Allan; Prakash, Y S; Agrawal, Anurag

    2016-05-01

    There is limited knowledge regarding the consequences of hyperinsulinemia on the lung. Given the increasing prevalence of obesity, insulin resistance, and epidemiological associations with asthma, this is a critical lacuna, more so with inhaled insulin on the horizon. Here, we demonstrate that insulin can adversely affect respiratory health. Insulin treatment (1 μg/ml) significantly (P < 0.05) increased the proliferation of primary human airway smooth muscle (ASM) cells and induced collagen release. Additionally, ASM cells showed a significant increase in calcium response and mitochondrial respiration upon insulin exposure. Mice administered intranasal insulin showed increased collagen deposition in the lungs as well as a significant increase in airway hyperresponsiveness. PI3K/Akt mediated activation of β-catenin, a positive regulator of epithelial-mesenchymal transition and fibrosis, was observed in the lungs of insulin-treated mice and lung cells. Our data suggests that hyperinsulinemia may have adverse effects on airway structure and function. Insulin-induced activation of β-catenin in lung tissue and the contractile effects on ASM cells may be causally related to the development of asthma-like phenotype. PMID:26919895

  20. Quercetin Affects Erythropoiesis and Heart Mitochondrial Function in Mice.

    PubMed

    Ruiz, Lina M; Salazar, Celia; Jensen, Erik; Ruiz, Paula A; Tiznado, William; Quintanilla, Rodrigo A; Barreto, Marlen; Elorza, Alvaro A

    2015-01-01

    Quercetin, a dietary flavonoid used as a food supplement, showed powerful antioxidant effects in different cellular models. However, recent in vitro and in vivo studies in mammals have suggested a prooxidant effect of quercetin and described an interaction with mitochondria causing an increase in O2 (∙-) production, a decrease in ATP levels, and impairment of respiratory chain in liver tissue. Therefore, because of its dual actions, we studied the effect of quercetin in vivo to analyze heart mitochondrial function and erythropoiesis. Mice were injected with 50 mg/kg of quercetin for 15 days. Treatment with quercetin decreased body weight, serum insulin, and ceruloplasmin levels as compared with untreated mice. Along with an impaired antioxidant capacity in plasma, quercetin-treated mice showed a significant delay on erythropoiesis progression. Heart mitochondrial function was also impaired displaying more protein oxidation and less activity for IV, respectively, than no-treated mice. In addition, a significant reduction in the protein expression levels of Mitofusin 2 and Voltage-Dependent Anion Carrier was observed. All these results suggest that quercetin affects erythropoiesis and mitochondrial function and then its potential use as a dietary supplement should be reexamined. PMID:26106459

  1. The transcriptional activities and cellular localization of the human estrogen receptor alpha are affected by the synonymous Ala87 mutation.

    PubMed

    Fernández-Calero, Tamara; Astrada, Soledad; Alberti, Alvaro; Horjales, Sofía; Arnal, Jean Francois; Rovira, Carlos; Bollati-Fogolín, Mariela; Flouriot, Gilles; Marin, Mónica

    2014-09-01

    Until recently, synonymous mutations (which do not change amino acids) have been much neglected. Some evidence suggests that this kind of mutations could affect mRNA secondary structure or stability, translation kinetics and protein structure. To explore deeper the role of synonymous mutations, we studied their consequence on the functional activity of the estrogen receptor alpha (ERα). The ERα is a ligand-inducible transcription factor that orchestrates pleiotropic cellular effects, at both genomic and non-genomic levels in response to estrogens. In this work we analyzed in transient transfection experiments, the activity of ERα carrying the synonymous mutation Ala87, a polymorphism involving about 5-10% of the population. In comparison to the wild type receptor, our results show that ERαA87 mutation reduces the transactivation efficiency of ERα on an ERE reporter gene while its expression level remains similar. This mutation enhances 4-OHT-induced transactivation of ERα on an AP1 reporter gene. Finally, the mutation affects the subcellular localization of ERα in a cell type specific manner. It enhances the cytoplasmic location of ERα without significant changes in non-genomic effects of E2. The functional alteration of the ERαA87 determined in this work highlights the relevance of synonymous mutations for biomedical and pharmacological points of view. PMID:24607813

  2. Cellular localization of long non-coding RNAs affects silencing by RNAi more than by antisense oligonucleotides.

    PubMed

    Lennox, Kim A; Behlke, Mark A

    2016-01-29

    Thousands of long non-coding RNAs (lncRNAs) have been identified in mammalian cells. Some have important functions and their dysregulation can contribute to a variety of disease states. However, most lncRNAs have not been functionally characterized. Complicating their study, lncRNAs have widely varying subcellular distributions: some reside predominantly in the nucleus, the cytoplasm or in both compartments. One method to query function is to suppress expression and examine the resulting phenotype. Methods to suppress expression of mRNAs include antisense oligonucleotides (ASOs) and RNA interference (RNAi). Antisense and RNAi-based gene-knockdown methods vary in efficacy between different cellular compartments. It is not known if this affects their ability to suppress lncRNAs. To address whether localization of the lncRNA influences susceptibility to degradation by either ASOs or RNAi, nuclear lncRNAs (MALAT1 and NEAT1), cytoplasmic lncRNAs (DANCR and OIP5-AS1) and dual-localized lncRNAs (TUG1, CasC7 and HOTAIR) were compared for knockdown efficiency. We found that nuclear lncRNAs were more effectively suppressed using ASOs, cytoplasmic lncRNAs were more effectively suppressed using RNAi and dual-localized lncRNAs were suppressed using both methods. A mixed-modality approach combining ASOs and RNAi reagents improved knockdown efficacy, particularly for those lncRNAs that localize to both nuclear and cytoplasmic compartments. PMID:26578588

  3. Does iron deficiency anemia affect olfactory function?

    PubMed

    Dinc, Mehmet Emre; Dalgic, Abdullah; Ulusoy, Seckin; Dizdar, Denizhan; Develioglu, Omer; Topak, Murat

    2016-07-01

    Conclusion This study found a negative effect of IDA on olfactory function. IDA leads to a reduction in olfactory function, and decreases in hemoglobin levels result in further reduction in olfactory function. Objective This study examined the effects of iron-deficiency anemia (IDA) on olfactory function. Method The study enrolled 50 IDA patients and 50 healthy subjects. Olfactory function was evaluated using the Sniffin' Sticks olfactory test. The diagnosis of IDA was made according to World Health Organization (WHO) criteria. Results Patients with IDA had a significantly lower threshold, discrimination, and identification (TDI) value, and a lower threshold compared with the control group. However, there were no significant differences between the groups in terms of smell selectivity values. PMID:26963317

  4. Photothermal cellular stimulation in functional bio-polymer interfaces.

    PubMed

    Martino, Nicola; Feyen, Paul; Porro, Matteo; Bossio, Caterina; Zucchetti, Elena; Ghezzi, Diego; Benfenati, Fabio; Lanzani, Guglielmo; Antognazza, Maria Rosa

    2015-01-01

    Hybrid interfaces between organic semiconductors and living tissues represent a new tool for in-vitro and in-vivo applications, bearing a huge potential, from basic researches to clinical applications. In particular, light sensitive conjugated polymers can be exploited as a new approach for optical modulation of cellular activity. In this work we focus on light-induced changes in the membrane potential of Human Embryonic Kidney (HEK-293) cells grown on top of a poly(3-hexylthiophene) (P3HT) thin film. On top of a capacitive charging of the polymer interface, we identify and fully characterize two concomitant mechanisms, leading to membrane depolarization and hyperpolarisation, both mediated by a thermal effect. Our results can be usefully exploited in the creation of a new platform for light-controlled cell manipulation, with possible applications in neuroscience and medicine. PMID:25753132

  5. Cellular MYCro Economics: Balancing MYC Function with MYC Expression

    PubMed Central

    Levens, David

    2013-01-01

    The expression levels of the MYC oncoprotein have long been recognized to be associated with the outputs of major cellular processes including proliferation, cell growth, apoptosis, differentiation, and metabolism. Therefore, to understand how MYC operates, it is important to define quantitatively the relationship between MYC input and expression output for its targets as well as the higher-order relationships between the expression levels of subnetwork components and the flow of information and materials through those networks. Two different views of MYC are considered, first as a molecular microeconomic manager orchestrating specific positive and negative responses at individual promoters in collaboration with other transcription and chromatin components, and second, as a macroeconomic czar imposing an overarching rule onto all active genes. In either case, c-myc promoter output requires multiple inputs and exploits diverse mechanisms to tune expression to the appropriate levels relative to the thresholds of expression that separate health and disease. PMID:24186489

  6. Photothermal cellular stimulation in functional bio-polymer interfaces

    PubMed Central

    Martino, Nicola; Feyen, Paul; Porro, Matteo; Bossio, Caterina; Zucchetti, Elena; Ghezzi, Diego; Benfenati, Fabio; Lanzani, Guglielmo; Antognazza, Maria Rosa

    2015-01-01

    Hybrid interfaces between organic semiconductors and living tissues represent a new tool for in-vitro and in-vivo applications, bearing a huge potential, from basic researches to clinical applications. In particular, light sensitive conjugated polymers can be exploited as a new approach for optical modulation of cellular activity. In this work we focus on light-induced changes in the membrane potential of Human Embryonic Kidney (HEK-293) cells grown on top of a poly(3-hexylthiophene) (P3HT) thin film. On top of a capacitive charging of the polymer interface, we identify and fully characterize two concomitant mechanisms, leading to membrane depolarization and hyperpolarisation, both mediated by a thermal effect. Our results can be usefully exploited in the creation of a new platform for light-controlled cell manipulation, with possible applications in neuroscience and medicine. PMID:25753132

  7. Mutations in MCT8 in patients with Allan-Herndon-Dudley-syndrome affecting its cellular distribution.

    PubMed

    Kersseboom, Simone; Kremers, Gert-Jan; Friesema, Edith C H; Visser, W Edward; Klootwijk, Wim; Peeters, Robin P; Visser, Theo J

    2013-05-01

    Monocarboxylate transporter 8 (MCT8) is a thyroid hormone (TH)-specific transporter. Mutations in the MCT8 gene are associated with Allan-Herndon-Dudley Syndrome (AHDS), consisting of severe psychomotor retardation and disturbed TH parameters. To study the functional consequences of different MCT8 mutations in detail, we combined functional analysis in different cell types with live-cell imaging of the cellular distribution of seven mutations that we identified in patients with AHDS. We used two cell models to study the mutations in vitro: 1) transiently transfected COS1 and JEG3 cells, and 2) stably transfected Flp-in 293 cells expressing a MCT8-cyan fluorescent protein construct. All seven mutants were expressed at the protein level and showed a defect in T3 and T4 transport in uptake and metabolism studies. Three mutants (G282C, P537L, and G558D) had residual uptake activity in Flp-in 293 and COS1 cells, but not in JEG3 cells. Four mutants (G221R, P321L, D453V, P537L) were expressed at the plasma membrane. The mobility in the plasma membrane of P537L was similar to WT, but the mobility of P321L was altered. The other mutants studied (insV236, G282C, G558D) were predominantly localized in the endoplasmic reticulum. In essence, loss of function by MCT8 mutations can be divided in two groups: mutations that result in partial or complete loss of transport activity (G221R, P321L, D453V, P537L) and mutations that mainly disturb protein expression and trafficking (insV236, G282C, G558D). The cell type-dependent results suggest that MCT8 mutations in AHDS patients may have tissue-specific effects on TH transport probably caused by tissue-specific expression of yet unknown MCT8-interacting proteins. PMID:23550058

  8. Anthocyanidins modulate the activity of human DNA topoisomerases I and II and affect cellular DNA integrity.

    PubMed

    Habermeyer, Michael; Fritz, Jessica; Barthelmes, Hans U; Christensen, Morten O; Larsen, Morten K; Boege, Fritz; Marko, Doris

    2005-09-01

    In the present study, we investigated the effect of anthocyanidins on human topoisomerases I and II and its relevance for DNA integrity within human cells. Anthocyanidins bearing vicinal hydroxy groups at the B-ring (delphinidin, DEL; cyanidin, CY) were found to potently inhibit the catalytic activity of human topoisomerases I and II, without discriminating between the IIalpha and the IIbeta isoforms. However, in contrast to topoisomerase poisons, DEL and CY did not stabilize the covalent DNA-topoisomerase intermediates (cleavable complex) of topoisomerase I or II. Using recombinant topoisomerase I, the presence of CY or DEL (> or = 1 microM) effectively prohibited the stabilization of the cleavable complex by the topoisomerase I poison camptothecin. We furthermore investigated whether the potential protective effect vs topoisomerase I poisons is reflected also on the cellular level, affecting the DNA damaging properties of camptothecin. Indeed, in HT29 cells, low micromolar concentrations of DEL (1-10 microM) significantly diminished the DNA strand breaking effect of camptothecin (100 microM). However, at concentrations > or = 50 microM, all anthocyanidins tested (delphinidin, cyanidin, malvidin, pelargonidin, and paeonidin), including those not interfering with topoisomerases, were found to induce DNA strand breaks in the comet assay. All of these analogues were able to compete with ethidium bromide for the intercalation into calf thymus DNA and to replace the minor groove binder Hoechst 33258. These data indicate substantial affinity to double-stranded DNA, which might contribute at least to the DNA strand breaking effect of anthocyanidins at higher concentrations (> or = 50 microM). PMID:16167831

  9. Propranolol affects stress-induced leukocytosis and cellular adhesion molecule expression.

    PubMed

    Kühlwein, E C; Irwin, M R; Ziegler, M G; Woods, V L; Kennedy, B; Mills, P J

    2001-12-01

    In this study, the impact of the beta-adrenergic antagonist propranolol on resting and acute psychological- and physical-stress-induced circulating leukocyte numbers and the density of cellular adhesion molecules was investigated. In a randomized double-blind crossover design, 45 healthy volunteers performed a 15-min public speaking task and 21 subjects performed a 16-min bicycle exercise after 5 days of ingesting a placebo and after 5 days of ingesting 100 mg/day propranolol. One week of ingesting propranolol modestly elevated the numbers of CD62L+ (P<0.019) but not CD62L- T-lymphocytes. Moreover, propranolol preferentially blunted-psychological stress-induced increases in naïve T-helper (CD4+CD62L+; P<0.049) and naïve T-cytotoxic lymphocytes (CD8+CD62L+; P<0.003), as well as activated T-cytotoxic lymphocytes (CD8+CD29+; P<0.005). However, exercise-induced increases in leukocyte numbers were enhanced following propranolol treatment (P<0.04). In contrast to the effect on the numbers of adhesion-molecule-bearing cells, there was only a modest effect of propranolol on stress-induced alterations of the density of CD62L, CD54 and CD11a. In this study, propranolol treatment interfered with the adrenergic regulation of circulating leukocyte numbers by blunting psychological stress effects but enhancing exercise effects. Propranolol affected the cell activation status to a lesser extent, as reflected by the density of adhesion molecules. PMID:11822472

  10. Protein coronas on gold nanorods passivated with amphiphilic ligands affect cytotoxicity and cellular response to penicillin/streptomycin.

    PubMed

    Kah, James Chen Yong; Grabinski, Christin; Untener, Emily; Garrett, Carol; Chen, John; Zhu, David; Hussain, Saber M; Hamad-Schifferli, Kimberly

    2014-05-27

    We probe how amphiphilic ligands (ALs) of four different types affect the formation of protein coronas on gold nanorods (NRs) and their impact on cellular response. NRs coated with cetyltrimethylammonium bromide were ligand exchanged with polyoxyethylene[10]cetyl ether, oligofectamine, and phosphatidylserine (PS). Protein coronas from equine serum (ES) were formed on these NR-ALs, and their colloidal stability, as well as cell uptake, proliferation, oxidative stress, and gene expression, were examined. We find that the protein corona that forms and its colloidal stability are affected by AL type and that the cellular response to these NR-AL-coronas (NR-AL-ES) is both ligand and corona dependent. We also find that the presence of common cell culture supplement penicillin/streptomycin can impact the colloidal stability and cellular response of NR-AL and NR-AL-ES, showing that the cell response is not necessarily inert to pen/strep when in the presence of nanoparticles. Although the protein corona is what the cells see, the underlying surface ligands evidently play an important role in shaping and defining the physical characteristics of the corona, which ultimately impacts the cellular response. Further, the results of this study suggest that the cellular behavior toward NR-AL is mediated by not only the type of AL and the protein corona it forms but also its resulting colloidal stability and interaction with cell culture supplements. PMID:24758495

  11. Mnk kinase pathway: Cellular functions and biological outcomes.

    PubMed

    Joshi, Sonali; Platanias, Leonidas C

    2014-08-26

    The mitogen-activated protein kinase (MAPK) interacting protein kinases 1 and 2 (Mnk1 and Mnk2) play important roles in controlling signals involved in mRNA translation. In addition to the MAPKs (p38 or Erk), multiple studies suggest that the Mnk kinases can be regulated by other known kinases such as Pak2 and/or other unidentified kinases by phosphorylation of residues distinct from the sites phosphorylated by the MAPKs. Several studies have established multiple Mnk protein targets, including PSF, heterogenous nuclear ribonucleoprotein A1, Sprouty 2 and have lead to the identification of distinct biological functions and substrate specificity for the Mnk kinases. In this review we discuss the pathways regulating the Mnk kinases, their known substrates as well as the functional consequences of engagement of pathways controlled by Mnk kinases. These kinases play an important role in mRNA translation via their regulation of eukaryotic initiation factor 4E (eIF4E) and their functions have important implications in tumor biology as well as the regulation of drug resistance to anti-oncogenic therapies. Other studies have identified a role for the Mnk kinases in cap-independent mRNA translation, suggesting that the Mnk kinases can exert important functional effects independently of the phosphorylation of eIF4E. The role of Mnk kinases in inflammation and inflammation-induced malignancies is also discussed. PMID:25225600

  12. VDAC2-specific cellular functions and the underlying structure.

    PubMed

    Naghdi, Shamim; Hajnóczky, György

    2016-10-01

    Voltage Dependent Anion-selective Channel 2 (VDAC2) contributes to oxidative metabolism by sharing a role in solute transport across the outer mitochondrial membrane (OMM) with other isoforms of the VDAC family, VDAC1 and VDAC3. Recent studies revealed that VDAC2 also has a distinctive role in mediating sarcoplasmic reticulum to mitochondria local Ca(2+) transport at least in cardiomyocytes, which is unlikely to be explained simply by the expression level of VDAC2. Furthermore, a strictly isoform-dependent VDAC2 function was revealed in the mitochondrial import and OMM-permeabilizing function of pro-apoptotic Bcl-2 family proteins, primarily Bak in many cell types. In addition, emerging evidence indicates a variety of other isoform-specific engagements for VDAC2. Since VDAC isoforms display 75% sequence similarity, the distinctive structure underlying VDAC2-specific functions is an intriguing problem. In this paper we summarize studies of VDAC2 structure and functions, which suggest a fundamental and exclusive role for VDAC2 in health and disease. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou. PMID:27116927

  13. Immunoglobulin levels and cellular immune function in lead exposed workers.

    PubMed

    Queiroz, M L; Perlingeiro, R C; Bincoletto, C; Almeida, M; Cardoso, M P; Dantas, D C

    1994-02-01

    The immunological status of lead acid battery workers with blood lead levels and urinary delta-aminolevulinic acid (ALA-U) concentrations ranging from safe to toxic levels has been examined and compared with those of non-exposed, age and sex matched controls. No differences in the serum concentrations of IgG, IgA and IgM between the populations were observed and there existed no correlation between blood lead level or ALA-U concentrations and serum immunoglobulin levels. In addition assessment was made of the capacity of peripheral blood mononuclear cells to respond to the mitogen phytohaemagglutinin (PHA), a correlate of T cell function. As before, there was no difference between exposed and control populations and no correlation between reactivity and blood lead concentration. Our data suggest that chronic exposure to lead fail to compromise lymphocyte function in man. PMID:8169320

  14. Extraocular muscle: cellular adaptations for a diverse functional repertoire.

    PubMed

    Porter, John D

    2002-04-01

    Oculomotor control systems are considerably more complex and diverse than are spinal skeletomotor systems. Moreover, individual skeletal muscles are frequently functional role-specific, while all extraocular muscles operate across a very wide dynamic range. We contend that the novel phenotype of the extraocular muscles is a direct consequence of the functional demands imposed upon this muscle group by the central eye movement controllers. This review highlights five basic themes of extraocular muscle biology that set them apart from more typical skeletal muscles, specifically, the (a) novel innervation pattern, (b) heterogeneity in contractile proteins, (c) structural and functional compartmentalization of the rectus and oblique muscles, (d) diversity of extraocular muscle fiber types, and (e) relationship between the novel muscle phenotype and the differential response of these muscles in neuromuscular and endocrine disease. Finally, new data from broad genome-wide profiling studies are reviewed, with global gene expression patterns lending substantial support to the notion that the extraocular muscles are fundamentally different from traditional skeletal muscle. This novel eye muscle phenotype represents an adaptation that exploits the full range of variability in skeletal muscle to meet the needs of visuomotor systems. PMID:11960789

  15. Molecular mechanism and cellular function of MHCII ubiquitination

    PubMed Central

    Oh, Jaehak; Shin, Jeoung-Sook

    2015-01-01

    Summary The major histocompatibility complex class II (MHCII) is ubiquitinated via the evolutionally conserved lysine in the cytoplasmic tail of the β chain in dendritic cells (DCs) and B cells. The ubiquitination is mediated by the membrane-associated RING-CH1 (MARCH1) ubiquitin ligase although it can be also mediated by the homolog ligase MARCH8 in model cell lines. The ubiquitination promotes MHCII endocytosis and lysosomal sorting that results in a reduction in the level of MHCII at cell surface. Functionally, MHCII ubiquitination serves as a means by which DCs suppress MHCII expression and reduce antigen presentation in response to the immune-regulatory cytokine IL-10 and regulatory T cells. Recently, additional roles of MHCII ubiquitination have begun to emerge. MHCII ubiquitination promoted DC production of inflammatory cytokines in response to the Toll-like receptor ligands. It also potentiated DC ability to activate antigen-specific naïve CD4+ T cells while limiting the amount of antigens presented at cell surface. Similarly, MHCII ubiquitination promoted DC activation of CD4+ thymocytes supporting regulatory T-cell development independent of its effect of limiting antigen presentation. Thus, ubiquitination appears to confer MHCII a function independent of presenting antigens by a mechanism yet to be identified. PMID:26085212

  16. Functional and Structural Mimicry of Cellular Protein Kinase A Anchoring Proteins by a Viral Oncoprotein

    PubMed Central

    King, Cason R.; Cohen, Michael J.; Fonseca, Gregory J.; Dirk, Brennan S.; Dikeakos, Jimmy D.; Mymryk, Joe S.

    2016-01-01

    The oncoproteins of the small DNA tumor viruses interact with a plethora of cellular regulators to commandeer control of the infected cell. During infection, adenovirus E1A deregulates cAMP signalling and repurposes it for activation of viral gene expression. We show that E1A structurally and functionally mimics a cellular A-kinase anchoring protein (AKAP). E1A interacts with and relocalizes protein kinase A (PKA) to the nucleus, likely to virus replication centres, via an interaction with the regulatory subunits of PKA. Binding to PKA requires the N-terminus of E1A, which bears striking similarity to the amphipathic α-helical domain present in cellular AKAPs. E1A also targets the same docking-dimerization domain of PKA normally bound by cellular AKAPs. In addition, the AKAP like motif within E1A could restore PKA interaction to a cellular AKAP in which its normal interaction motif was deleted. During infection, E1A successfully competes with endogenous cellular AKAPs for PKA interaction. E1A’s role as a viral AKAP contributes to viral transcription, protein expression and progeny production. These data establish HAdV E1A as the first known viral AKAP. This represents a unique example of viral subversion of a crucial cellular regulatory pathway via structural mimicry of the PKA interaction domain of cellular AKAPs. PMID:27137912

  17. Media composition: antioxidants/chelators and cellular function.

    PubMed

    Combelles, Catherine M H; Hennet, Margo L

    2012-01-01

    Protection of embryos against oxidative insults during culture is necessary to maintain viability. Generation of excessive levels of reactive oxygen species (ROS) is triggered by various components of the in vitro environment, most of which embryos do not normally encounter in vivo. To compensate for these deficiencies in the culture environment, antioxidants and chelators are often used to control or suppress ROS levels as embryos develop. However, there is no consensus regarding dosage, time of exposure, or appropriate combinations of antioxidants and chelators in embryo culture. In order to elucidate this aspect of an embryo's chemical surroundings in vitro, we present the current knowledge on the function and effect of each antioxidant or chelator that is often included in an embryo culture medium. PMID:22829373

  18. Cellular functions of phosphatidylinositol 3-phosphate and FYVE domain proteins.

    PubMed Central

    Gillooly, D J; Simonsen, A; Stenmark, H

    2001-01-01

    PtdIns3P is a phosphoinositide 3-kinase product that has been strongly implicated in regulating membrane trafficking in both mammalian and yeast cells. PtdIns3P has been shown to be specifically located on membranes associated with the endocytic pathway. Proteins that contain FYVE zinc-finger domains are recruited to PtdIns3P-containing membranes. Structural information is now available concerning the interaction between FYVE domains and PtdIns3P. A number of proteins have been identified which contain a FYVE domain, and in this review we discuss the functions of PtdIns3P and its FYVE-domain-containing effector proteins in membrane trafficking, cytoskeletal regulation and receptor signalling. PMID:11284710

  19. Cellular Functions of Optineurin in Health and Disease.

    PubMed

    Slowicka, Karolina; Vereecke, Lars; van Loo, Geert

    2016-09-01

    Optineurin (OPTN) was initially identified as a regulator of NF-κB and interferon signaling, but attracted most attention because of its association with various human disorders such as glaucoma, Paget disease of bone, and amyotrophic lateral sclerosis. Importantly, OPTN has recently been identified as an autophagy receptor important for the autophagic removal of pathogens, damaged mitochondria, and protein aggregates. This activity is most likely compromised in patients carrying OPTN mutations, and contributes to the observed phenotypes. In this review we summarize recent studies describing the molecular mechanisms by which OPTN controls immunity and autophagy, and discuss these findings in the context of several diseases that have been associated with OPTN (mal)function. PMID:27480243

  20. Integrative Chemistry: Advanced functional cellular materials bearing multiscale porosity

    NASA Astrophysics Data System (ADS)

    Depardieu, M.; Kinadjian, N.; Backov, R.

    2015-07-01

    With this mini review we show through the sol-gel and emulsion-based Integrative Chemistry how it is possible to trigger materials dimensionality and beyond their functionalities when reaching enhanced applications. In here we focus on 3D macrocellular monolithic foams bearing hierarchical porosities and applications thereof. We first depict the general background of emulsions focusing on concentrated ones, acting as soft templates for the design of PolyHIPE foams, HIPE being the acronym of High Internal Phase Emulsions while encompassing both sol-gel and polymer chemistry. Secondly we extend this approach toward the design of hybrid organic-inorganic foams, labeled Organo-Si(HIPE), where photonics and heterogeneous catalysis applications are addressed. In a third section we show how inorganic Si(HIPE) matrices can be employed as sacrificial hard templates for the generation carbonaceous foams, labeled Carbon(HIPE). These foams being conductive we show applications when employed as electrodes for Li-S battery and as hosts for Li(BH4)-based hydrogen storage.

  1. Multicompartmentalized polymeric systems: towards biomimetic cellular structure and function.

    PubMed

    Marguet, Maïté; Bonduelle, Colin; Lecommandoux, Sébastien

    2013-01-21

    The cell is certainly one of the most complex and exciting systems in Nature that scientists are still trying to fully understand. Such a challenge pushes material scientists to seek to reproduce its perfection by building biomimetic materials with high-added value and previously unmatched properties. Thanks to their versatility, their robustness and the current state of polymer chemistry science, we believe polymer-based materials to constitute or represent ideal candidates when addressing the challenge of biomimicry, which defines the focus of this review. The first step consists in mimicking the structure of the cell: its inner compartments, the organelles, with a multicompartmentalized structure, and the rest, i.e. the cytoplasm minus the organelles (mainly cytoskeleton/cytosol) with gels or particular solutions (highly concentrated for example) in one compartment, and finally the combination of both. Achieving this first structural step enables us to considerably widen the gap of possibilities in drug delivery systems. Another powerful property of the cell lies in its metabolic function. The second step is therefore to achieve enzymatic reactions in a compartment, as occurs in the organelles, in a highly controlled, selective and efficient manner. We classify the most exciting polymersome nanoreactors reported in our opinion into two different subsections, depending on their very final concept or purpose of design. We also highlight in a thorough table the experimental sections crucial to such work. Finally, after achieving control over these prerequisites, scientists are able to combine them and push the frontiers of biomimicry further: from cell structure mimics towards a controlled biofunctionality. Such a biomimetic approach in material design and the future research it will stimulate, are believed to bring considerable enrichments to the fields of drug delivery, (bio)sensors, (bio)catalysis and (bio)technology. PMID:23073077

  2. Molecular and cellular targets affected by green tea extracts in vascular cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of green or black tea has been associated with a lower risk for the development of cardiovascular diseases, but despite many studies, a firm connection has not been delineated. Several molecular and cellular mechanisms may play a role in the preventive activity of tea. As reviewed here, ...

  3. Physiological enzymology: The next frontier in understanding protein structure and function at the cellular level.

    PubMed

    Lee, Irene; Berdis, Anthony J

    2016-01-01

    Historically, the study of proteins has relied heavily on characterizing the activity of a single purified protein isolated from other cellular components. This classic approach allowed scientists to unambiguously define the intrinsic kinetic and chemical properties of that protein. The ultimate hope was to extrapolate this information toward understanding how the enzyme or receptor behaves within its native cellular context. These types of detailed in vitro analyses were necessary to reduce the innate complexities of measuring the singular activity and biochemical properties of a specific enzyme without interference from other enzymes and potential competing substrates. However, recent developments in fields encompassing cell biology, molecular imaging, and chemical biology now provide the unique chemical tools and instrumentation to study protein structure, function, and regulation in their native cellular environment. These advancements provide the foundation for a new field, coined physiological enzymology, which quantifies the function and regulation of enzymes and proteins at the cellular level. In this Special Edition, we explore the area of Physiological Enzymology and Protein Function through a series of review articles that focus on the tools and techniques used to measure the cellular activity of proteins inside living cells. This article is part of a Special Issue entitled: Physiological Enzymology and Protein Functions. PMID:26277093

  4. Deletion or Overexpression of Mitochondrial NAD+ Carriers in Saccharomyces cerevisiae Alters Cellular NAD and ATP Contents and Affects Mitochondrial Metabolism and the Rate of Glycolysis ▿

    PubMed Central

    Agrimi, Gennaro; Brambilla, Luca; Frascotti, Gianni; Pisano, Isabella; Porro, Danilo; Vai, Marina; Palmieri, Luigi

    2011-01-01

    The modification of enzyme cofactor concentrations can be used as a method for both studying and engineering metabolism. We varied Saccharomyces cerevisiae mitochondrial NAD levels by altering expression of its specific mitochondrial carriers. Changes in mitochondrial NAD levels affected the overall cellular concentration of this coenzyme and the cellular metabolism. In batch culture, a strain with a severe NAD depletion in mitochondria succeeded in growing, albeit at a low rate, on fully respiratory media. Although the strain increased the efficiency of its oxidative phosphorylation, the ATP concentration was low. Under the same growth conditions, a strain with a mitochondrial NAD concentration higher than that of the wild type similarly displayed a low cellular ATP level, but its growth rate was not affected. In chemostat cultures, when cellular metabolism was fully respiratory, both mutants showed low biomass yields, indicative of impaired energetic efficiency. The two mutants increased their glycolytic fluxes, and as a consequence, the Crabtree effect was triggered at lower dilution rates. Strikingly, the mutants switched from a fully respiratory metabolism to a respirofermentative one at the same specific glucose flux as that of the wild type. This result seems to indicate that the specific glucose uptake rate and/or glycolytic flux should be considered one of the most important independent variables for establishing the long-term Crabtree effect. In cells growing under oxidative conditions, bioenergetic efficiency was affected by both low and high mitochondrial NAD availability, which suggests the existence of a critical mitochondrial NAD concentration in order to achieve optimal mitochondrial functionality. PMID:21335394

  5. Irradiation affects cellular properties and Eph receptor expression in human melanoma cells

    PubMed Central

    Mosch, Birgit; Pietzsch, Doreen; Pietzsch, Jens

    2012-01-01

    X-ray irradiation influences metastatic properties of tumor cells and, moreover, metastasis and cellular motility can be modified by members of the Eph receptor/ephrin family of receptor tyrosine kinases. We hypothesized that irradiation-induced changes in cellular properties relevant for metastasis in melanoma cells could be mediated by Eph receptor/ephrin signaling. In this pilot study, we analyzed one pre-metastatic (Mel-Juso) and three metastatic human melanoma (Mel-Juso-L3, A375, and A2058) cells lines and predominantly found anti-metastatic effects of X-ray irradiation with impaired cell growth, clonal growth and motility. Additionally, we observed an irradiation-induced increase in adhesion paralleled by a decrease in migration in Mel-Juso and Mel-Juso-L3 cells and, in part, also in A375 cells. We further demonstrate a decrease of EphA2 both in expression and activity at 7 d after irradiation paralleled by an upregulation of EphA3. Analyzing downstream signaling after irradiation, we detected decreased Src kinase phosphorylation, but unchanged focal adhesion kinase (FAK) phosphorylation, indicating, in part, irradiation-induced downregulation of signaling via the EphA2-Src-FAK axis in melanoma cells. However, to which extent this finding contributes to the modification of metastasis-relevant cellular properties remains to be elucidated. PMID:22568947

  6. Social functioning and age across affective and non-affective psychoses

    PubMed Central

    Martin, Elizabeth A.; Öngür, Dost; Cohen, Bruce M.; Lewandowski, Kathryn E.

    2014-01-01

    Both non-affective and affective psychoses are associated with deficits in social functioning across the course of the illness. However, it is not clear how social functioning varies among diagnostic groups as a function of age. The current study examined the relationship between social functioning and age in schizophrenia (SZ), schizoaffective disorder (SZA), and psychotic bipolar disorder (PBD). We found that individuals with PBD had the highest functioning while individuals with SZ had the poorest. The functioning of individuals with SZA fell in between the other groups. We also found that older ages were associated with poorer functioning. Although there was not a significant diagnostic group by age interaction, visual inspection of our data suggests a subtly steeper trajectory of decline in PBD. These results indicate that a decline in social functioning with may be an important area of unmet need in treatment across psychotic disorders. PMID:25503785

  7. Thymus-associated parathyroid hormone has two cellular origins with distinct endocrine and immunological functions.

    PubMed

    Liu, Zhijie; Farley, Alison; Chen, Lizhen; Kirby, Beth J; Kovacs, Christopher S; Blackburn, C Clare; Manley, Nancy R

    2010-01-01

    In mammals, parathyroid hormone (PTH) is a key regulator of extracellular calcium and inorganic phosphorus homeostasis. Although the parathyroid glands were thought to be the only source of PTH, extra-parathyroid PTH production in the thymus, which shares a common origin with parathyroids during organogenesis, has been proposed to provide an auxiliary source of PTH, resulting in a higher than expected survival rate for aparathyroid Gcm2⁻/⁻ mutants. However, the developmental ontogeny and cellular identity of these "thymic" PTH-expressing cells is unknown. We found that the lethality of aparathyroid Gcm2⁻/⁻ mutants was affected by genetic background without relation to serum PTH levels, suggesting a need to reconsider the physiological function of thymic PTH. We identified two sources of extra-parathyroid PTH in wild-type mice. Incomplete separation of the parathyroid and thymus organs during organogenesis resulted in misplaced, isolated parathyroid cells that were often attached to the thymus; this was the major source of thymic PTH in normal mice. Analysis of thymus and parathyroid organogenesis in human embryos showed a broadly similar result, indicating that these results may provide insight into human parathyroid development. In addition, medullary thymic epithelial cells (mTECs) express PTH in a Gcm2-independent manner that requires TEC differentiation and is consistent with expression as a self-antigen for negative selection. Genetic or surgical removal of the thymus indicated that thymus-derived PTH in Gcm2⁻/⁻ mutants did not provide auxiliary endocrine function. Our data show conclusively that the thymus does not serve as an auxiliary source of either serum PTH or parathyroid function. We further show that the normal process of parathyroid organogenesis in both mice and humans leads to the generation of multiple small parathyroid clusters in addition to the main parathyroid glands, that are the likely source of physiologically relevant "thymic

  8. On the Quest of Cellular Functions of PEA-15 and the Therapeutic Opportunities

    PubMed Central

    Wei, Yufeng

    2015-01-01

    Phosphoprotein enriched in astrocytes, 15 KDa (PEA-15), a ubiquitously expressed small protein in all mammals, is known for decades for its potent interactions with various protein partners along distinct biological pathways. Most notable interacting partners of PEA-15 include extracellular signal-regulated kinase 1 and 2 (ERK1/2) in the mitogen activated protein kinase (MAPK) pathway, the Fas-associated death domain (FADD) protein involving in the formation of the death-inducing signaling complex (DISC), and the phospholipase D1 (PLD1) affecting the insulin sensitivity. However, the actual cellular functions of PEA-15 are still mysterious, and the question why this protein is expressed in almost all cell and tissue types remains unanswered. Here we synthesize the most recent structural, biological, and clinical studies on PEA-15 with emphases on its anti-apoptotic, anti-proliferative, and anti-inflammative properties, and propose a converged protective role of PEA-15 that maintains the balance of death and survival in different cell types. Under conditions that this delicate balance is unsustainable, PEA-15 may become pathological and lead to various diseases, including cancers and diabetes. Targeting PEA-15 interactions, or the use of PEA-15 protein as therapeutics, may provide a wider window of opportunities to treat these diseases. PMID:26263999

  9. Functional diversity of protein phosphatase-1, a cellular economizer and reset button.

    PubMed

    Ceulemans, Hugo; Bollen, Mathieu

    2004-01-01

    The protein serine/threonine phosphatase protein phosphatase-1 (PP1) is a ubiquitous eukaryotic enzyme that regulates a variety of cellular processes through the dephosphorylation of dozens of substrates. This multifunctionality of PP1 relies on its association with a host of function-specific targetting and substrate-specifying proteins. In this review we discuss how PP1 affects the biochemistry and physiology of eukaryotic cells. The picture of PP1 that emerges from this analysis is that of a "green" enzyme that promotes the rational use of energy, the recycling of protein factors, and a reversal of the cell to a basal and/or energy-conserving state. Thus PP1 promotes a shift to the more energy-efficient fuels when nutrients are abundant and stimulates the storage of energy in the form of glycogen. PP1 also enables the relaxation of actomyosin fibers, the return to basal patterns of protein synthesis, and the recycling of transcription and splicing factors. In addition, PP1 plays a key role in the recovery from stress but promotes apoptosis when cells are damaged beyond repair. Furthermore, PP1 downregulates ion pumps and transporters in various tissues and ion channels that are involved in the excitation of neurons. Finally, PP1 promotes the exit from mitosis and maintains cells in the G1 or G2 phases of the cell cycle. PMID:14715909

  10. Slight temperature changes affect protein affinity and cellular uptake/toxicity of nanoparticles

    NASA Astrophysics Data System (ADS)

    Mahmoudi, Morteza; Shokrgozar, Mohammad A.; Behzadi, Shahed

    2013-03-01

    It is known that what the cell actually ``sees'' at the nanoscale is an outer shell formed of `protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular/organ temperature.It is known that what the cell actually ``sees'' at the nanoscale is an outer shell formed of `protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular

  11. Copper transporters and chaperones: Their function on angiogenesis and cellular signalling.

    PubMed

    Bharathi Devi, S R; Dhivya M, Aloysius; Sulochana, K N

    2016-09-01

    Copper, although known as a micronutrient, has a pivotal role in modulating the cellular metabolism. Many studies have reported the role of copper in angiogenesis. Copper chaperones are intracellular proteins that mediate copper trafficking to various cell organelles. However, the role and function of copper chaperones in relation to angiogenesis has to be further explored. The intracellular copper levels when in excess are deleterious and certain mutations of copper chaperones have been shown to induce cell death and influence various cellular metabolisms. The study of these chaperones will be helpful in understanding the players in the cascade of events in angiogenesis and their role in cellular metabolic pathways. In this review we have briefly listed the copper chaperones associated with angiogenic and metabolic signalling and their function. PMID:27581939

  12. Global functional analyses of cellular responses to pore-forming toxins.

    PubMed

    Kao, Cheng-Yuan; Los, Ferdinand C O; Huffman, Danielle L; Wachi, Shinichiro; Kloft, Nicole; Husmann, Matthias; Karabrahimi, Valbona; Schwartz, Jean-Louis; Bellier, Audrey; Ha, Christine; Sagong, Youn; Fan, Hui; Ghosh, Partho; Hsieh, Mindy; Hsu, Chih-Shen; Chen, Li; Aroian, Raffi V

    2011-03-01

    Here we present the first global functional analysis of cellular responses to pore-forming toxins (PFTs). PFTs are uniquely important bacterial virulence factors, comprising the single largest class of bacterial protein toxins and being important for the pathogenesis in humans of many Gram positive and Gram negative bacteria. Their mode of action is deceptively simple, poking holes in the plasma membrane of cells. The scattered studies to date of PFT-host cell interactions indicate a handful of genes are involved in cellular defenses to PFTs. How many genes are involved in cellular defenses against PFTs and how cellular defenses are coordinated are unknown. To address these questions, we performed the first genome-wide RNA interference (RNAi) screen for genes that, when knocked down, result in hypersensitivity to a PFT. This screen identifies 106 genes (∼0.5% of genome) in seven functional groups that protect Caenorhabditis elegans from PFT attack. Interactome analyses of these 106 genes suggest that two previously identified mitogen-activated protein kinase (MAPK) pathways, one (p38) studied in detail and the other (JNK) not, form a core PFT defense network. Additional microarray, real-time PCR, and functional studies reveal that the JNK MAPK pathway, but not the p38 MAPK pathway, is a key central regulator of PFT-induced transcriptional and functional responses. We find C. elegans activator protein 1 (AP-1; c-jun, c-fos) is a downstream target of the JNK-mediated PFT protection pathway, protects C. elegans against both small-pore and large-pore PFTs and protects human cells against a large-pore PFT. This in vivo RNAi genomic study of PFT responses proves that cellular commitment to PFT defenses is enormous, demonstrates the JNK MAPK pathway as a key regulator of transcriptionally-induced PFT defenses, and identifies AP-1 as the first cellular component broadly important for defense against large- and small-pore PFTs. PMID:21408619

  13. Oxidized (non)-regenerated cellulose affects fundamental cellular processes of wound healing

    PubMed Central

    Wagenhäuser, M. U.; Mulorz, J.; Ibing, W.; Simon, F.; Spin, J. M.; Schelzig, H.; Oberhuber, A.

    2016-01-01

    In this study we investigated how hemostats such as oxidized regenerated cellulose (ORC, TABOTAMP) and oxidized non-regenerated cellulose (ONRC, RESORBA CELL) influence local cellular behavior and contraction of the extracellular matrix (ECM). Human stromal fibroblasts were inoculated in vitro with ORC and ONRC. Cell proliferation was assayed over time, and migration was evaluated by Live Cell imaging microscopy. Fibroblasts grown in collagen-gels were treated with ORC or ONRC, and ECM contraction was measured utilizing a contraction assay. An absolute pH decline was observed with both ORC and ONRC after 1 hour. Mean daily cell proliferation, migration and matrix contraction were more strongly inhibited by ONRC when compared with ORC (p < 0.05). When control media was pH-lowered to match the lower pH values typically seen with ORC and ONRC, significant differences in cell proliferation and migration were still observed between ONRC and ORC (p < 0.05). However, in these pH conditions, inhibition of matrix contraction was only significant for ONRC (p < 0.05). We find that ORC and ONRC inhibit fibroblast proliferation, migration and matrix contraction, and stronger inhibition of these essential cellular processes of wound healing were observed for ONRC when compared with ORC. These results will require further validation in future in vivo experiments to clarify the clinical implications for hemostat use in post-surgical wound healing. PMID:27557881

  14. Oxidized (non)-regenerated cellulose affects fundamental cellular processes of wound healing.

    PubMed

    Wagenhäuser, M U; Mulorz, J; Ibing, W; Simon, F; Spin, J M; Schelzig, H; Oberhuber, A

    2016-01-01

    In this study we investigated how hemostats such as oxidized regenerated cellulose (ORC, TABOTAMP) and oxidized non-regenerated cellulose (ONRC, RESORBA CELL) influence local cellular behavior and contraction of the extracellular matrix (ECM). Human stromal fibroblasts were inoculated in vitro with ORC and ONRC. Cell proliferation was assayed over time, and migration was evaluated by Live Cell imaging microscopy. Fibroblasts grown in collagen-gels were treated with ORC or ONRC, and ECM contraction was measured utilizing a contraction assay. An absolute pH decline was observed with both ORC and ONRC after 1 hour. Mean daily cell proliferation, migration and matrix contraction were more strongly inhibited by ONRC when compared with ORC (p < 0.05). When control media was pH-lowered to match the lower pH values typically seen with ORC and ONRC, significant differences in cell proliferation and migration were still observed between ONRC and ORC (p < 0.05). However, in these pH conditions, inhibition of matrix contraction was only significant for ONRC (p < 0.05). We find that ORC and ONRC inhibit fibroblast proliferation, migration and matrix contraction, and stronger inhibition of these essential cellular processes of wound healing were observed for ONRC when compared with ORC. These results will require further validation in future in vivo experiments to clarify the clinical implications for hemostat use in post-surgical wound healing. PMID:27557881

  15. How Does Maternal Employment Affect Children's Socioemotional Functioning?

    ERIC Educational Resources Information Center

    Lam, Gigi

    2015-01-01

    The maternal employment becomes an irreversible trend across the globe. The effect of maternal employment on children's socioemotional functioning is so pervasive that it warrants special attention to investigate into the issue. A trajectory of analytical framework of how maternal employment affects children's socioemotional functioning originates…

  16. Ocean acidification affects competition for space: projections of community structure using cellular automata.

    PubMed

    McCoy, Sophie J; Allesina, Stefano; Pfister, Catherine A

    2016-03-16

    Historical ecological datasets from a coastal marine community of crustose coralline algae (CCA) enabled the documentation of ecological changes in this community over 30 years in the Northeast Pacific. Data on competitive interactions obtained from field surveys showed concordance between the 1980s and 2013, yet also revealed a reduction in how strongly species interact. Here, we extend these empirical findings with a cellular automaton model to forecast ecological dynamics. Our model suggests the emergence of a new dominant competitor in a global change scenario, with a reduced role of herbivory pressure, or trophic control, in regulating competition among CCA. Ocean acidification, due to its energetic demands, may now instead play this role in mediating competitive interactions and thereby promote species diversity within this guild. PMID:26936244

  17. Cellular Intrinsic Mechanism Affecting the Outcome of AML Treated with Ara-C in a Syngeneic Mouse Model

    PubMed Central

    Tan, Dongming; Su, Guangsong; Zheng, Yanwen; He, Chao; Mao, Zhengwei J.; Singleton, Timothy P.; Yin, Bin

    2014-01-01

    The mechanisms underlying acute myeloid leukemia (AML) treatment failure are not clear. Here, we established a mouse model of AML by syngeneic transplantation of BXH-2 derived myeloid leukemic cells and developed an efficacious Ara-C-based regimen for treatment of these mice. We proved that leukemic cell load was correlated with survival. We also demonstrated that the susceptibility of leukemia cells to Ara-C could significantly affect the survival. To examine the molecular alterations in cells with different sensitivity, genome-wide expression of the leukemic cells was profiled, revealing that overall 366 and 212 genes became upregulated or downregulated, respectively, in the resistant cells. Many of these genes are involved in the regulation of cell cycle, cellular proliferation, and apoptosis. Some of them were further validated by quantitative PCR. Interestingly, the Ara-C resistant cells retained the sensitivity to ABT-737, an inhibitor of anti-apoptosis proteins, and treatment with ABT-737 prolonged the life span of mice engrafted with resistant cells. These results suggest that leukemic load and intrinsic cellular resistance can affect the outcome of AML treated with Ara-C. Incorporation of apoptosis inhibitors, such as ABT-737, into traditional cytotoxic regimens merits consideration for the treatment of AML in a subset of patients with resistance to Ara-C. This work provided direct in vivo evidence that leukemic load and intrinsic cellular resistance can affect the outcome of AML treated with Ara-C, suggesting that incorporation of apoptosis inhibitors into traditional cytotoxic regimens merits consideration for the treatment of AML in a subset of patients with resistance to Ara-C. PMID:25314317

  18. Quantum dots for tracking cellular transport of lectin-functionalized nanoparticles

    SciTech Connect

    Gao Xiaoling; Wang Tao; Wu Bingxian; Chen Jun; Chen Jiyao; Yue Yang; Dai Ning; Chen Hongzhuan Jiang Xinguo

    2008-12-05

    Successful drug delivery by functionalized nanocarriers largely depends on their efficient intracellular transport which has not yet been fully understood. We developed a new tracking technique by encapsulating quantum dots into the core of wheat germ agglutinin-conjugated nanoparticles (WGA-NP) to track cellular transport of functionalized nanocarriers. The resulting nanoparticles showed no changes in particle size, zeta potential or biobinding activity, and the loaded probe presented excellent photostability and tracking ability. Taking advantage of these properties, cellular transport profiles of WGA-NP in Caco-2 cells was demonstrated. The cellular uptake begins with binding of WGA to its receptor at the cell surface. The subsequent endocytosis happened in a cytoskeleton-dependent manner and by means of clathrin and caveolae-mediated mechanisms. After endosome creating, transport occurs to both trans-Golgi and lysosome. Our study provides new evidences for quantum dots as a cellular tracking probe of nanocarriers and helps understand intracellular transport profile of lectin-functionalized nanoparticles.

  19. Function of Membrane Rafts in Viral Lifecycles and Host Cellular Response

    PubMed Central

    Takahashi, Tadanobu; Suzuki, Takashi

    2011-01-01

    Membrane rafts are small (10–200 nm) sterol- and sphingolipid-enriched domains that compartmentalize cellular processes. Membrane rafts play an important role in viral infection cycles and viral virulence. Viruses are divided into four main classes, enveloped DNA virus, enveloped RNA virus, nonenveloped DNA virus, and nonenveloped RNA virus. General virus infection cycle is also classified into two sections, the early stage (entry process) and the late stage (assembly, budding, and release processes of virus particles). In the viral cycle, membrane rafts act as a scaffold of many cellular signal transductions, which are associated with symptoms caused by viral infections. In this paper, we describe the functions of membrane rafts in viral lifecycles and host cellular response according to each virus classification, each stage of the virus lifecycle, and each virus-induced signal transduction. PMID:22191032

  20. Fetal radiofrequency radiation exposure from 800-1900 mhz-rated cellular telephones affects neurodevelopment and behavior in mice.

    PubMed

    Aldad, Tamir S; Gan, Geliang; Gao, Xiao-Bing; Taylor, Hugh S

    2012-01-01

    Neurobehavioral disorders are increasingly prevalent in children, however their etiology is not well understood. An association between prenatal cellular telephone use and hyperactivity in children has been postulated, yet the direct effects of radiofrequency radiation exposure on neurodevelopment remain unknown. Here we used a mouse model to demonstrate that in-utero radiofrequency exposure from cellular telephones does affect adult behavior. Mice exposed in-utero were hyperactive and had impaired memory as determined using the object recognition, light/dark box and step-down assays. Whole cell patch clamp recordings of miniature excitatory postsynaptic currents (mEPSCs) revealed that these behavioral changes were due to altered neuronal developmental programming. Exposed mice had dose-responsive impaired glutamatergic synaptic transmission onto layer V pyramidal neurons of the prefrontal cortex. We present the first experimental evidence of neuropathology due to in-utero cellular telephone radiation. Further experiments are needed in humans or non-human primates to determine the risk of exposure during pregnancy. PMID:22428084

  1. Protein source and choice of anticoagulant decisively affect nanoparticle protein corona and cellular uptake

    NASA Astrophysics Data System (ADS)

    Schöttler, S.; Klein, Katja; Landfester, K.; Mailänder, V.

    2016-03-01

    Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance of the choice of protein source used for in vitro protein corona analysis is concisely investigated. Major and decisive differences in cellular uptake of a polystyrene nanoparticle incubated in fetal bovine serum, human serum, human citrate and heparin plasma are reported. Furthermore, the protein compositions are determined for coronas formed in the respective incubation media. A strong influence of heparin, which is used as an anticoagulant for plasma generation, on cell interaction is demonstrated. While heparin enhances the uptake into macrophages, it prevents internalization into HeLa cells. Taken together we can give the recommendation that human plasma anticoagulated with citrate seems to give the most relevant results for in vitro studies of nanoparticle uptake.Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance

  2. Mps1 (Monopolar Spindle 1) Protein Inhibition Affects Cellular Growth and Pro-Embryogenic Masses Morphology in Embryogenic Cultures of Araucaria angustifolia (Araucariaceae)

    PubMed Central

    Douétts-Peres, Jackellinne C.; Cruz, Marco Antônio L.; Reis, Ricardo S.; Heringer, Angelo S.; de Oliveira, Eduardo A. G.; Elbl, Paula M.; Floh, Eny I. S.; Silveira, Vanildo

    2016-01-01

    Somatic embryogenesis has been shown to be an efficient tool for studying processes based on cell growth and development. The fine regulation of the cell cycle is essential for proper embryo formation during the process of somatic embryogenesis. The aims of the present work were to identify and perform a structural and functional characterization of Mps1 and to analyze the effects of the inhibition of this protein on cellular growth and pro-embryogenic mass (PEM) morphology in embryogenic cultures of A. angustifolia. A single-copy Mps1 gene named AaMps1 was retrieved from the A. angustifolia transcriptome database, and through a mass spectrometry approach, AaMps1 was identified and quantified in embryogenic cultures. The Mps1 inhibitor SP600125 (10 μM) inhibited cellular growth and changed PEMs, and these effects were accompanied by a reduction in AaMps1 protein levels in embryogenic cultures. Our work has identified the Mps1 protein in a gymnosperm species for the first time, and we have shown that inhibiting Mps1 affects cellular growth and PEM differentiation during A. angustifolia somatic embryogenesis. These data will be useful for better understanding cell cycle control during somatic embryogenesis in plants. PMID:27064899

  3. Protein source and choice of anticoagulant decisively affect nanoparticle protein corona and cellular uptake.

    PubMed

    Schöttler, S; Klein, Katja; Landfester, K; Mailänder, V

    2016-03-14

    Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance of the choice of protein source used for in vitro protein corona analysis is concisely investigated. Major and decisive differences in cellular uptake of a polystyrene nanoparticle incubated in fetal bovine serum, human serum, human citrate and heparin plasma are reported. Furthermore, the protein compositions are determined for coronas formed in the respective incubation media. A strong influence of heparin, which is used as an anticoagulant for plasma generation, on cell interaction is demonstrated. While heparin enhances the uptake into macrophages, it prevents internalization into HeLa cells. Taken together we can give the recommendation that human plasma anticoagulated with citrate seems to give the most relevant results for in vitro studies of nanoparticle uptake. PMID:26804616

  4. Modification of Cellular Cholesterol Content Affects Traction Force, Adhesion and Cell Spreading

    PubMed Central

    Norman, Leann L.; Oetama, Ratna J.; Dembo, Micah; Byfield, F.; Hammer, Daniel A.; Levitan, Irena; Aranda-Espinoza, Helim

    2011-01-01

    Cellular cholesterol is a critical component of the plasma membrane, and plays a key role in determining the physical properties of the lipid bilayer, such as elasticity, viscosity, and permeability. Surprisingly, it has been shown that cholesterol depletion increases cell stiffness, not due to plasma membrane stiffening, but rather, due to the interaction between the actin cytoskeleton and the plasma membrane. This indicates that traction stresses of the acto-myosin complex likely increase during cholesterol depletion. Here we use force traction microscopy to quantify the forces individual cells are exerting on the substrate, and total internal reflection fluorescence microscopy as well as interference reflection microscopy to observe cell–substrate adhesion and spreading. We show that single cells depleted of cholesterol produce larger traction forces and have large focal adhesions compared to untreated or cholesterol-enriched cells. Cholesterol depletion also causes a decrease in adhesion area for both single cells and monolayers. Spreading experiments illustrate a decrease in spreading area for cholesterol-depleted cells, and no effect on cholesterol-enriched cells. These results demonstrate that cholesterol plays an important role in controlling and regulating the cell–substrate interactions through the actin–plasma membrane complex, cell–cell adhesion, and spreading. PMID:21461187

  5. Histological Lesions and Cellular Response in the Skin of Alpine Chamois (Rupicapra r. rupicapra) Spontaneously Affected by Sarcoptic Mange

    PubMed Central

    Salvadori, Claudia; Lazzarotti, Camilla; Trogu, Tiziana; Lanfranchi, Paolo

    2016-01-01

    Population dynamics of chamois (genus Rupicapra, subfamily Caprinae) can be influenced by infectious diseases epizootics, of which sarcoptic mange is probably the most severe in the Alpine chamois (Rupicapra rupicapra rupicapra). In this study, skin lesions and cellular inflammatory infiltrates were characterized in 44 Alpine chamois affected by sarcoptic mange. Dermal cellular responses were evaluated in comparison with chamois affected by trombiculosis and controls. In both sarcoptic mange and trombiculosis, a significantly increase of eosinophils, mast cells, T and B lymphocytes, and macrophages was detected. Moreover, in sarcoptic mange significant higher numbers of T lymphocytes and macrophages compared to trombiculosis were observed. Lesions in sarcoptic mange were classified in three grades, according to crusts thickness, correlated with mite counts. Grade 3 represented the most severe form with crust thickness more than 3.5 mm, high number of mites, and severe parakeratosis with diffuse bacteria. Evidence of immediate and delayed hypersensitivity was detected in all three forms associated with diffuse severe epidermal hyperplasia. In grade 3, a significant increase of B lymphocytes was evident compared to grades 1 and 2, while eosinophil counts were significantly higher than in grade 1, but lower than in grade 2 lesions. An involvement of nonprotective Th2 immune response could in part account for severe lesions of grade 3. PMID:27403422

  6. Nanostructures of Designed Geometry and Functionality Enable Regulation of Cellular Signaling Processes

    PubMed Central

    Li, Jie-Ren; Shi, Lifang; Deng, Zhao; Lo, Su Hao; Liu, Gang-yu

    2014-01-01

    Extracellular matrices (ECM) triggered cellular signaling processes often begin with the clustering of the cellular receptors such as integrin and FcεRI. The sizes of these initial protein complexes or clusters are tens to 100 nm in dimension; therefore, engineered nanostructures could provide effective mimics of ECM for investigation and control of the initial and downstream specific signaling process. This current topic discusses recent advances in nanotechnology in the context of design and production of matching chemical functionality and geometry for control of specific cellular signaling processes. Two investigations are reported to demonstrate this concept: (a) how the presentation of antigen at nanometer scale would influence the aggregation of FcεRI, which would impact the formation of activation complexes, leading to rearrangement of actin in cytoskeleton and degranulation or activation of mast cells; (b) how the engineered nanostructure could guide the initial integrin clustering, which would impact the formation of focal adhesion and downstream cell signaling cascades, leading to polarization, migration and morphological changes. Complimentary to engineered ECMs using synthetic ligands or peptides, or topographic control at micrometer scale, nanostructures of designed geometry and chemical functionality provide new and effective biochemical cues for regulation of cellular signaling processes and downstream behaviors. PMID:22783801

  7. SUMO1 Affects Synaptic Function, Spine Density and Memory

    PubMed Central

    Matsuzaki, Shinsuke; Lee, Linda; Knock, Erin; Srikumar, Tharan; Sakurai, Mikako; Hazrati, Lili-Naz; Katayama, Taiichi; Staniszewski, Agnieszka; Raught, Brian; Arancio, Ottavio; Fraser, Paul E.

    2015-01-01

    Small ubiquitin-like modifier-1 (SUMO1) plays a number of roles in cellular events and recent evidence has given momentum for its contributions to neuronal development and function. Here, we have generated a SUMO1 transgenic mouse model with exclusive overexpression in neurons in an effort to identify in vivo conjugation targets and the functional consequences of their SUMOylation. A high-expressing line was examined which displayed elevated levels of mono-SUMO1 and increased high molecular weight conjugates in all brain regions. Immunoprecipitation of SUMOylated proteins from total brain extract and proteomic analysis revealed ~95 candidate proteins from a variety of functional classes, including a number of synaptic and cytoskeletal proteins. SUMO1 modification of synaptotagmin-1 was found to be elevated as compared to non-transgenic mice. This observation was associated with an age-dependent reduction in basal synaptic transmission and impaired presynaptic function as shown by altered paired pulse facilitation, as well as a decrease in spine density. The changes in neuronal function and morphology were also associated with a specific impairment in learning and memory while other behavioral features remained unchanged. These findings point to a significant contribution of SUMO1 modification on neuronal function which may have implications for mechanisms involved in mental retardation and neurodegeneration. PMID:26022678

  8. SUMO1 Affects Synaptic Function, Spine Density and Memory.

    PubMed

    Matsuzaki, Shinsuke; Lee, Linda; Knock, Erin; Srikumar, Tharan; Sakurai, Mikako; Hazrati, Lili-Naz; Katayama, Taiichi; Staniszewski, Agnieszka; Raught, Brian; Arancio, Ottavio; Fraser, Paul E

    2015-01-01

    Small ubiquitin-like modifier-1 (SUMO1) plays a number of roles in cellular events and recent evidence has given momentum for its contributions to neuronal development and function. Here, we have generated a SUMO1 transgenic mouse model with exclusive overexpression in neurons in an effort to identify in vivo conjugation targets and the functional consequences of their SUMOylation. A high-expressing line was examined which displayed elevated levels of mono-SUMO1 and increased high molecular weight conjugates in all brain regions. Immunoprecipitation of SUMOylated proteins from total brain extract and proteomic analysis revealed ~95 candidate proteins from a variety of functional classes, including a number of synaptic and cytoskeletal proteins. SUMO1 modification of synaptotagmin-1 was found to be elevated as compared to non-transgenic mice. This observation was associated with an age-dependent reduction in basal synaptic transmission and impaired presynaptic function as shown by altered paired pulse facilitation, as well as a decrease in spine density. The changes in neuronal function and morphology were also associated with a specific impairment in learning and memory while other behavioral features remained unchanged. These findings point to a significant contribution of SUMO1 modification on neuronal function which may have implications for mechanisms involved in mental retardation and neurodegeneration. PMID:26022678

  9. Simultaneous characterization of cellular RNA structure and function with in-cell SHAPE-Seq

    PubMed Central

    Watters, Kyle E.; Abbott, Timothy R.; Lucks, Julius B.

    2016-01-01

    Many non-coding RNAs form structures that interact with cellular machinery to control gene expression. A central goal of molecular and synthetic biology is to uncover design principles linking RNA structure to function to understand and engineer this relationship. Here we report a simple, high-throughput method called in-cell SHAPE-Seq that combines in-cell probing of RNA structure with a measurement of gene expression to simultaneously characterize RNA structure and function in bacterial cells. We use in-cell SHAPE-Seq to study the structure–function relationship of two RNA mechanisms that regulate translation in Escherichia coli. We find that nucleotides that participate in RNA–RNA interactions are highly accessible when their binding partner is absent and that changes in RNA structure due to RNA–RNA interactions can be quantitatively correlated to changes in gene expression. We also characterize the cellular structures of three endogenously expressed non-coding RNAs: 5S rRNA, RNase P and the btuB riboswitch. Finally, a comparison between in-cell and in vitro folded RNA structures revealed remarkable similarities for synthetic RNAs, but significant differences for RNAs that participate in complex cellular interactions. Thus, in-cell SHAPE-Seq represents an easily approachable tool for biologists and engineers to uncover relationships between sequence, structure and function of RNAs in the cell. PMID:26350218

  10. Simultaneous characterization of cellular RNA structure and function with in-cell SHAPE-Seq.

    PubMed

    Watters, Kyle E; Abbott, Timothy R; Lucks, Julius B

    2016-01-29

    Many non-coding RNAs form structures that interact with cellular machinery to control gene expression. A central goal of molecular and synthetic biology is to uncover design principles linking RNA structure to function to understand and engineer this relationship. Here we report a simple, high-throughput method called in-cell SHAPE-Seq that combines in-cell probing of RNA structure with a measurement of gene expression to simultaneously characterize RNA structure and function in bacterial cells. We use in-cell SHAPE-Seq to study the structure-function relationship of two RNA mechanisms that regulate translation in Escherichia coli. We find that nucleotides that participate in RNA-RNA interactions are highly accessible when their binding partner is absent and that changes in RNA structure due to RNA-RNA interactions can be quantitatively correlated to changes in gene expression. We also characterize the cellular structures of three endogenously expressed non-coding RNAs: 5S rRNA, RNase P and the btuB riboswitch. Finally, a comparison between in-cell and in vitro folded RNA structures revealed remarkable similarities for synthetic RNAs, but significant differences for RNAs that participate in complex cellular interactions. Thus, in-cell SHAPE-Seq represents an easily approachable tool for biologists and engineers to uncover relationships between sequence, structure and function of RNAs in the cell. PMID:26350218

  11. Serotonin and Dopamine: Unifying Affective, Activational, and Decision Functions

    PubMed Central

    Cools, Roshan; Nakamura, Kae; Daw, Nathaniel D

    2011-01-01

    Serotonin, like dopamine (DA), has long been implicated in adaptive behavior, including decision making and reinforcement learning. However, although the two neuromodulators are tightly related and have a similar degree of functional importance, compared with DA, we have a much less specific understanding about the mechanisms by which serotonin affects behavior. Here, we draw on recent work on computational models of dopaminergic function to suggest a framework by which many of the seemingly diverse functions associated with both DA and serotonin—comprising both affective and activational ones, as well as a number of other functions not overtly related to either—can be seen as consequences of a single root mechanism. PMID:20736991

  12. TDP-43 affects splicing profiles and isoform production of genes involved in the apoptotic and mitotic cellular pathways

    PubMed Central

    De Conti, Laura; Akinyi, Maureen V.; Mendoza-Maldonado, Ramiro; Romano, Maurizio; Baralle, Marco; Buratti, Emanuele

    2015-01-01

    In recent times, high-throughput screening analyses have broadly defined the RNA cellular targets of TDP-43, a nuclear factor involved in neurodegeneration. A common outcome of all these studies is that changing the expression levels of this protein can alter the expression of several hundred RNAs within cells. What still remains to be clarified is which changes represent direct cellular targets of TDP-43 or just secondary variations due to the general role played by this protein in RNA metabolism. Using an HTS-based splicing junction analysis we identified at least six bona fide splicing events that are consistent with being controlled by TDP-43. Validation of the data, both in neuronal and non-neuronal cell lines demonstrated that TDP-43 substantially alters the levels of isoform expression in four genes potentially important for neuropathology: MADD/IG20, STAG2, FNIP1 and BRD8. For MADD/IG20 and STAG2, these changes could also be confirmed at the protein level. These alterations were also observed in a cellular model that successfully mimics TDP-43 loss of function effects following its aggregation. Most importantly, our study demonstrates that cell cycle alterations induced by TDP-43 knockdown can be recovered by restoring the STAG2, an important component of the cohesin complex, normal splicing profile. PMID:26261209

  13. Inhibitory effects of lysophosphatidic acid receptor-5 on cellular functions of sarcoma cells.

    PubMed

    Araki, Mutsumi; Kitayoshi, Misaho; Dong, Yan; Hirane, Miku; Ozaki, Shuhei; Mori, Shiori; Fukushima, Nobuyuki; Honoki, Kanya; Tsujiuchi, Toshifumi

    2014-06-01

    Lysophosphatidic acid (LPA) is a bioactive lipid that interacts with G protein-coupled LPA receptors (LPA receptor-1 (LPA1) to LPA6). Here, we investigated the effects of LPA signaling via LPA5 on cellular functions of sarcoma cells by generating Lpar5 overexpressing and Lpar5 knockdown cells from rat osteosarcoma and malignant fibrous histiocytoma cells, respectively. The cell motility activity of Lpar5 overexpressing cells was significantly lower, while Lpar5 knockdown cells showed high cell motility, compared with respective controls. Gelatin zymography showed that LPA5 suppressed the activation of matrix metalloproteinase-2. LPA5 also inhibited the cell motility activity of endothelial cells, correlating with the expression levels of vascular endothelial growth factor genes. These results suggest that LPA signaling via LPA5 negatively regulates the cellular functions of rat sarcoma cells. PMID:24798396

  14. Cellular and molecular mechanisms affecting tumour radiosensitivity : An in vitro study

    NASA Astrophysics Data System (ADS)

    Power, Olive Mary

    The response of tumour cells in vitro to ionising radiation can, to a certain extent, predict the response of tumours to various radiotherapy treatment modalities. This thesis considers some of the factors known to be involved in the radiation response of human tumour cells in vitro. These parameters include radiation-induced cell-cycle perturbations, apoptosis and DNA damage repair. A panel of eight human tumour cell lines with markedly differing radiosensitivities were assessed in order to determine the key factors governing their radiation response. A wide range of doses spanning both the low dose region (0-2 Gy and 0-5 Gy) and the clinically relevant region (1-4 Gy) were used to determine whether differences in responses could distinguish cells which were radiosensitive or resistant. Ionising radiation produced a cell cycle delay in all cell lines in one or both of the cellular checkpoints. A Gl/S delay was detected in those cell lines that expressed wild-type p53, and the duration of this delay appeared to be directly related to the level of constitutive protein. p53 protein stabilisation was observed after 4 h, even at doses of 0-2 Gy, although a Gl/S delay was only detectable at higher doses. There was no direct relationship between p53 status and survival although wild-type p53 expression was more prevalent in the radiosensitive cell lines (3/4 sensitives are wild-type versus 2/4 resistants). A G2/M delay could only be detected at doses of > 1 Gy. This delay appeared to be dose independent in the resistant cell lines, suggesting a threshold dose of IGy, above which no further effect is observed. A radiation-induced reduction of cyclin B1 protein was observed in all cell lines implicating this protein in the induction of a G2/M delay. The duration of G2/M delay was significantly longer in the radiosensitive cell lines at 4 Gy (7-20 h versus 4-6 h at 4 Gy). The proportion of cells that exited the G2/M block and re-entered GO/G1 phase was also significantly

  15. USP1 deubiquitinase: cellular functions, regulatory mechanisms and emerging potential as target in cancer therapy

    PubMed Central

    2013-01-01

    Reversible protein ubiquitination is emerging as a key process for maintaining cell homeostasis, and the enzymes that participate in this process, in particular E3 ubiquitin ligases and deubiquitinases (DUBs), are increasingly being regarded as candidates for drug discovery. Human DUBs are a group of approximately 100 proteins, whose cellular functions and regulatory mechanisms remain, with some exceptions, poorly characterized. One of the best-characterized human DUBs is ubiquitin-specific protease 1 (USP1), which plays an important role in the cellular response to DNA damage. USP1 levels, localization and activity are modulated through several mechanisms, including protein-protein interactions, autocleavage/degradation and phosphorylation, ensuring that USP1 function is carried out in a properly regulated spatio-temporal manner. Importantly, USP1 expression is deregulated in certain types of human cancer, suggesting that USP1 could represent a valid target in cancer therapy. This view has gained recent support with the finding that USP1 inhibition may contribute to revert cisplatin resistance in an in vitro model of non-small cell lung cancer (NSCLC). Here, we describe the current knowledge on the cellular functions and regulatory mechanisms of USP1. We also summarize USP1 alterations found in cancer, combining data from the literature and public databases with our own data. Finally, we discuss the emerging potential of USP1 as a target, integrating published data with our novel findings on the effects of the USP1 inhibitor pimozide in combination with cisplatin in NSCLC cells. PMID:23937906

  16. Modeling physicochemical interactions affecting in vitro cellular dosimetry of engineered nanomaterials: application to nanosilver

    PubMed Central

    Mukherjee, Dwaipayan; Leo, Bey Fen; Royce, Steven G.; Porter, Alexandra E.; Ryan, Mary P.; Schwander, Stephan; Chung, Kian Fan; Tetley, Teresa D.; Zhang, Junfeng; Georgopoulos, Panos G.

    2014-01-01

    Engineered nanomaterials (ENMs) possess unique characteristics affecting their interactions in biological media and biological tissues. Systematic investigation of the effects of particle properties on biological toxicity requires a comprehensive modeling framework which can be used to predict ENM particokinetics in a variety of media. The Agglomeration-diffusion-sedimentation-reaction model (ADSRM) described here is stochastic, using a direct simulation Monte Carlo method to study the evolution of nanoparticles in biological media, as they interact with each other and with the media over time. Nanoparticle diffusion, gravitational settling, agglomeration, and dissolution are treated in a mechanistic manner with focus on silver ENMs (AgNPs). The ADSRM model utilizes particle properties such as size, density, zeta potential, and coating material, along with medium properties like density, viscosity, ionic strength, and pH, to model evolving patterns in a population of ENMs along with their interaction with associated ions and molecules. The model predictions for agglomeration and dissolution are compared with in vitro measurements for various types of ENMs, coating materials, and incubation media, and are found to be overall consistent with measurements. The model has been implemented for an in vitro case in cell culture systems to inform in vitro dosimetry for toxicology studies, and can be directly extended to other biological systems, including in vivo tissue subsystems by suitably modifying system geometry. PMID:25598696

  17. Mutations affecting sensitivity of the cellular slime mold Dictyostelium discoideum to DNA-damaging agents.

    PubMed

    Bronner, C E; Welker, D L; Deering, R A

    1992-09-01

    We describe 22 new mutants of D. discoideum that are sensitive to DNA damage. These mutants were isolated on the basis of sensitivity to either temperature, gamma-rays, or 4-nitroquinolone-1-oxide (4NQO). The doses of gamma-rays, ultraviolet light (UV), and 4NQO required to reduce the survival of colony-forming ability of these mutants to 10% (D10) range from 2% to 100% of the D10s for the nonmutant, parent strains. For most of the mutants, those which are very sensitive to one agent are very sensitive to all agents tested and those which are moderately sensitive to one agent, are moderately sensitive to all agents tested. One mutant is sensitive only to 4NQO. Linkage relationships have been examined for 13 of these mutants. This linkage information was used to design complementation tests to determine allelism with previously characterized complementation groups affecting sensitivity to radiation. 4 of the new mutants fall within previously identified complementation groups and 3 new complementation groups have been identified (radJ, radK and radL). Other new loci probably also exist among these new mutants. This brings the number of characterized mutants of D. discoideum which are sensitive to DNA-damaging agents to 33 and the number of assigned complementation groups to 11. PMID:1380652

  18. Cigarette smoke extract affects mitochondrial function in alveolar epithelial cells.

    PubMed

    Ballweg, Korbinian; Mutze, Kathrin; Königshoff, Melanie; Eickelberg, Oliver; Meiners, Silke

    2014-12-01

    Cigarette smoke is the main risk factor for chronic obstructive pulmonary disease (COPD). Exposure of cells to cigarette smoke induces an initial adaptive cellular stress response involving increased oxidative stress and induction of inflammatory signaling pathways. Exposure of mitochondria to cellular stress alters their fusion/fission dynamics. Whereas mild stress induces a prosurvival response termed stress-induced mitochondrial hyperfusion, severe stress results in mitochondrial fragmentation and mitophagy. In the present study, we analyzed the mitochondrial response to mild and nontoxic doses of cigarette smoke extract (CSE) in alveolar epithelial cells. We characterized mitochondrial morphology, expression of mitochondrial fusion and fission genes, markers of mitochondrial proteostasis, as well as mitochondrial functions such as membrane potential and oxygen consumption. Murine lung epithelial (MLE)12 and primary mouse alveolar epithelial cells revealed pronounced mitochondrial hyperfusion upon treatment with CSE, accompanied by increased expression of the mitochondrial fusion protein mitofusin 2 and increased metabolic activity. We did not observe any alterations in mitochondrial proteostasis, i.e., induction of the mitochondrial unfolded protein response or mitophagy. Therefore, our data indicate an adaptive prosurvival response of mitochondria of alveolar epithelial cells to nontoxic concentrations of CSE. A hyperfused mitochondrial network, however, renders the cell more vulnerable to additional stress, such as sustained cigarette smoke exposure. As such, cigarette smoke-induced mitochondrial hyperfusion, although part of a beneficial adaptive stress response in the first place, may contribute to the pathogenesis of COPD. PMID:25326581

  19. Functions of the cellular prion protein, the end of Moore's law, and Ockham's razor theory.

    PubMed

    del Río, José A; Gavín, Rosalina

    2016-01-01

    Since its discovery the cellular prion protein (encoded by the Prnp gene) has been associated with a large number of functions. The proposed functions rank from basic cellular processes such as cell cycle and survival to neural functions such as behavior and neuroprotection, following a pattern similar to that of Moore's law for electronics. In addition, particular interest is increasing in the participation of Prnp in neurodegeneration. However, in recent years a redefinition of these functions has begun, since examples of previously attributed functions were increasingly re-associated with other proteins. Most of these functions are linked to so-called "Prnp-flanking genes" that are close to the genomic locus of Prnp and which are present in the genome of some Prnp mouse models. In addition, their role in neuroprotection against convulsive insults has been confirmed in recent studies. Lastly, in recent years a large number of models indicating the participation of different domains of the protein in apoptosis have been uncovered. However, after more than 10 years of molecular dissection our view is that the simplest mechanistic model in PrP(C)-mediated cell death should be considered, as Ockham's razor theory suggested. PMID:26890218

  20. Functions of the cellular prion protein, the end of Moore's law, and Ockham's razor theory

    PubMed Central

    del Río, José A.; Gavín, Rosalina

    2016-01-01

    ABSTRACT Since its discovery the cellular prion protein (encoded by the Prnp gene) has been associated with a large number of functions. The proposed functions rank from basic cellular processes such as cell cycle and survival to neural functions such as behavior and neuroprotection, following a pattern similar to that of Moore's law for electronics. In addition, particular interest is increasing in the participation of Prnp in neurodegeneration. However, in recent years a redefinition of these functions has begun, since examples of previously attributed functions were increasingly re-associated with other proteins. Most of these functions are linked to so-called “Prnp-flanking genes” that are close to the genomic locus of Prnp and which are present in the genome of some Prnp mouse models. In addition, their role in neuroprotection against convulsive insults has been confirmed in recent studies. Lastly, in recent years a large number of models indicating the participation of different domains of the protein in apoptosis have been uncovered. However, after more than 10 years of molecular dissection our view is that the simplest mechanistic model in PrPC-mediated cell death should be considered, as Ockham's razor theory suggested. PMID:26890218

  1. Telomere protein RAP1 levels are affected by cellular aging and oxidative stress

    PubMed Central

    Swanson, Mark J.; Baribault, Michelle E.; Israel, Joanna N.; Bae, Nancy S.

    2016-01-01

    Telomeres are important for maintaining the integrity of the genome through the action of the shelterin complex. Previous studies indicted that the length of the telomere did not have an effect on the amount of the shelterin subunits; however, those experiments were performed using immortalized cells with stable telomere lengths. The interest of the present study was to observe how decreasing telomere lengths over successive generations would affect the shelterin subunits. As neonatal human dermal fibroblasts aged and their telomeres became shorter, the levels of the telomere-binding protein telomeric repeat factor 2 (TRF2) decreased significantly. By contrast, the levels of one of its binding partners, repressor/activator protein 1 (RAP1), decreased to a lesser extent than would be expected from the decrease in TRF2. Other subunits, TERF1-interacting nuclear factor 2 and protection of telomeres protein 1, remained stable. The decrease in RAP1 in the older cells occurred in the nuclear and cytoplasmic fractions. Hydrogen peroxide (H2O2) stress was used as an artificial means of aging in the cells, and this resulted in RAP1 levels decreasing, but the effect was only observed in the nuclear portion. Similar results were obtained using U251 glioblastoma cells treated with H2O2 or grown in serum-depleted medium. The present findings indicate that TRF2 and RAP1 levels decrease as fibroblasts naturally age. RAP1 remains more stable compared to TRF2. RAP1 also responds to oxidative stress, but the response is different to that observed in aging. PMID:27446538

  2. Lifetime affect and midlife cognitive function: prospective birth cohort study

    PubMed Central

    Richards, M.; Barnett, J. H.; Xu, M. K.; Croudace, T. J.; Gaysina, D.; Kuh, D.; Jones, P. B.

    2014-01-01

    Background Recurrent affective problems are predictive of cognitive impairment, but the timing and directionality, and the nature of the cognitive impairment, are unclear. Aims To test prospective associations between life-course affective symptoms and cognitive function in late middle age. Method A total of 1668 men and women were drawn from the Medical Research Council National Survey of Health and Development (the British 1946 birth cohort). Longitudinal affective symptoms spanning age 13-53 years served as predictors; outcomes consisted of self-reported memory problems at 60-64 years and decline in memory and information processing from age 53 to 60-64 years. Results Regression analyses revealed no clear pattern of association between longitudinal affective symptoms and decline in cognitive test scores, after adjusting for gender, childhood cognitive ability, education and midlife socioeconomic status. In contrast, affective symptoms were strongly, diffusely and independently associated with self-reported memory problems. Conclusions Affective symptoms are more clearly associated with self-reported memory problems in late midlife than with objectively measured cognitive performance. PMID:24357571

  3. Does Subacromial Osteolysis Affect Shoulder Function after Clavicle Hook Plating?

    PubMed Central

    Sun, Siwei; Gan, Minfeng; Sun, Han; Wu, Guizhong; Yang, Huilin; Zhou, Feng

    2016-01-01

    Purpose. To evaluate whether subacromial osteolysis, one of the major complications of the clavicle hook plate procedure, affects shoulder function. Methods. We had performed a retrospective study of 72 patients diagnosed with a Neer II lateral clavicle fracture or Degree-III acromioclavicular joint dislocation in our hospital from July 2012 to December 2013. All these patients had undergone surgery with clavicle hook plate and were divided into two groups based on the occurrence of subacromial osteolysis. By using the Constant-Murley at the first follow-up visit after plates removal, we evaluated patients' shoulder function to judge if it has been affected by subacromial osteolysis. Results. We have analyzed clinical data for these 72 patients, which shows that there is no significant difference between group A (39 patients) and group B (33 patients) in age, gender, injury types or side, and shoulder function (the Constant-Murley scores are 93.38 ± 3.56 versus 94.24 ± 3.60, P > 0.05). Conclusion. The occurrence of subacromial osteolysis is not rare, and also it does not significantly affect shoulder function. PMID:27034937

  4. THE MITOCHONDRIAL PARADIGM FOR CARDIOVASCULAR DISEASE SUSCEPTIBILITY AND CELLULAR FUNCTION: A COMPLEMENTARY CONCEPT TO MENDELIAN GENETICS

    PubMed Central

    Kryzwanski, David M.; Moellering, Douglas; Fetterman, Jessica L.; Dunham-Snary, Kimberly J.; Sammy, Melissa J.; Ballinger, Scott W.

    2013-01-01

    While there is general agreement that cardiovascular disease (CVD) development is influenced by a combination of genetic, environmental, and behavioral contributors, the actual mechanistic basis of how these factors initiate or promote CVD development in some individuals while others with identical risk profiles do not, is not clearly understood. This review considers the potential role for mitochondrial genetics and function in determining CVD susceptibility from the standpoint that the original features that molded cellular function were based upon mitochondrial-nuclear relationships established millions of years ago and were likely refined during prehistoric environmental selection events that today, are largely absent. Consequently, contemporary risk factors that influence our susceptibility to a variety of age-related diseases, including CVD were probably not part of the dynamics that defined the processes of mitochondrial – nuclear interaction, and thus, cell function. In this regard, the selective conditions that contributed to cellular functionality and evolution should be given more consideration when interpreting and designing experimental data and strategies. Finally, future studies that probe beyond epidemiologic associations are required. These studies will serve as the initial steps for addressing the provocative concept that contemporary human disease susceptibility is the result of selection events for mitochondrial function that increased chances for prehistoric human survival and reproductive success. PMID:21647091

  5. Identification of multiple cellular uptake pathways of polystyrene nanoparticles and factors affecting the uptake: relevance for drug delivery systems.

    PubMed

    Firdessa, Rebuma; Oelschlaeger, Tobias A; Moll, Heidrun

    2014-01-01

    Nanoparticles may address challenges by human diseases through improving diagnosis, vaccination and treatment. The uptake mechanism regulates the type of threat a particle poses on the host cells and how a cell responds to it. Hence, understanding the uptake mechanisms and cellular interactions of nanoparticles at the cellular and subcellular level is a prerequisite for their effective biomedical applications. The present study shows the uptake mechanisms of polystyrene nanoparticles and factors affecting their uptake in bone marrow-derived macrophages, 293T kidney epithelial cells and L929 fibroblasts. Labeling with the endocytic marker FM4-64 and transmission electron microscopy studies show that the nanoparticles were internalized rapidly via endocytosis and accumulated in intracellular vesicles. Soon after their internalizations, nanoparticles trafficked to organelles with acidic pH. Analysis of the ultrastructural morphology of the plasma membrane invaginations or extravasations provides clear evidence for the involvement of several uptake routes in parallel to internalize a given type of nanoparticles by mammalian cells, highlighting the complexity of the nanoparticle-cell interactions. Blocking the specific endocytic pathways by different pharmacological inhibitors shows similar outcomes. The potential to take up nanoparticles varies highly among different cell types in a particle sizes-, time- and energy-dependent manner. Furthermore, infection and the activation status of bone marrow-derived macrophages significantly affect the uptake potential of the cells, indicating the need to understand the diseases' pathogenesis to establish effective and rational drug-delivery systems. This study enhances our understanding of the application of nanotechnology in biomedical sciences. PMID:25224362

  6. Expression of virus-encoded proteinases: functional and structural similarities with cellular enzymes.

    PubMed Central

    Dougherty, W G; Semler, B L

    1993-01-01

    Many viruses express their genome, or part of their genome, initially as a polyprotein precursor that undergoes proteolytic processing. Molecular genetic analyses of viral gene expression have revealed that many of these processing events are mediated by virus-encoded proteinases. Biochemical activity studies and structural analyses of these viral enzymes reveal that they have remarkable similarities to cellular proteinases. However, the viral proteinases have evolved unique features that permit them to function in a cellular environment. In this article, the current status of plant and animal virus proteinases is described along with their role in the viral replication cycle. The reactions catalyzed by viral proteinases are not simple enzyme-substrate interactions; rather, the processing steps are highly regulated, are coordinated with other viral processes, and frequently involve the participation of other factors. Images PMID:8302216

  7. Understanding the Cellular Function of TRPV2 Channel through Generation of Specific Monoclonal Antibodies

    PubMed Central

    Cohen, Matthew R.; Huynh, Kevin W.; Cawley, Daniel; Moiseenkova-Bell, Vera Y.

    2013-01-01

    Transient receptor potential vanilloid 2 (TRPV2) is a Ca2+-permeable nonselective cation channel proposed to play a critical role in a wide array of cellular processes. Although TRPV2 surface expression was originally determined to be sensitive to growth factor signaling, regulated trafficking of TRPV2 has remained controversial. TRPV2 has proven difficult to study due to the lack of specific pharmacological tools to modulate channel activity; therefore, most studies of the cellular function of TRPV2 rely on immuno-detection techniques. Polyclonal antibodies against TRPV2 have not been properly validated and characterized, which may contribute to conflicting results regarding its function in the cell. Here, we developed monoclonal antibodies using full-length TRPV2 as an antigen. Extensive characterization of these antibodies and comparison to commonly used commercially available TRPV2 antibodies revealed that while monoclonal antibodies generated in our laboratory were suitable for detection of endogenous TRPV2 by western blot, immunoprecipitation and immunocytochemistry, the commercially available polyclonal antibodies we tested were not able to recognize endogenous TRPV2. We used our newly generated and validated TRPV2 antibodies to determine the effects of insulin-like growth factor 1 (IGF-1) on TRPV2 surface expression in heterologous and endogenous expression systems. We found that IGF-1 had little to no effect on trafficking and plasma membrane expression of TRPV2. Overall, these new TRPV2 monoclonal antibodies served to dispel the controversy of the effects of IGF-1 on TRPV2 plasma membrane expression and will clarify the role TRPV2 plays in cellular function. Furthermore, our strategy of using full-length tetrameric TRP channels may allow for the generation of antibodies against other TRP channels of unclear function. PMID:24392006

  8. Cellular distribution and cytotoxicity of graphene quantum dots with different functional groups

    PubMed Central

    2014-01-01

    Graphene quantum dots (GQDs) have been developed as promising optical probes for bioimaging due to their excellent photoluminescent properties. Additionally, the fluorescence spectrum and quantum yield of GQDs are highly dependent on the surface functional groups on the carbon sheets. However, the distribution and cytotoxicity of GQDs functionalized with different chemical groups have not been specifically investigated. Herein, the cytotoxicity of three kinds of GQDs with different modified groups (NH2, COOH, and CO-N (CH3)2, respectively) in human A549 lung carcinoma cells and human neural glioma C6 cells was investigated using thiazoyl blue colorimetric (MTT) assay and trypan blue assay. The cellular apoptosis or necrosis was then evaluated by flow cytometry analysis. It was demonstrated that the three modified GQDs showed good biocompatibility even when the concentration reached 200 μg/mL. The Raman spectra of cells treated with GQDs with different functional groups also showed no distinct changes, affording molecular level evidence for the biocompatibility of the three kinds of GQDs. The cellular distribution of the three modified GQDs was observed using a fluorescence microscope. The data revealed that GQDs randomly dispersed in the cytoplasm but not diffused into nucleus. Therefore, GQDs with different functional groups have low cytotoxicity and excellent biocompatibility regardless of chemical modification, offering good prospects for bioimaging and other biomedical applications. PMID:24597852

  9. The cellular bromodomain protein Brd4 has multiple functions in E2-mediated papillomavirus transcription activation.

    PubMed

    Helfer, Christine M; Yan, Junpeng; You, Jianxin

    2014-08-01

    The cellular bromodomain protein Brd4 functions in multiple processes of the papillomavirus life cycle, including viral replication, genome maintenance, and gene transcription through its interaction with the viral protein, E2. However, the mechanisms by which E2 and Brd4 activate viral transcription are still not completely understood. In this study, we show that recruitment of positive transcription elongation factor b (P-TEFb), a functional interaction partner of Brd4 in transcription activation, is important for E2's transcription activation activity. Furthermore, chromatin immunoprecipitation (ChIP) analyses demonstrate that P-TEFb is recruited to the actual papillomavirus episomes. We also show that E2's interaction with cellular chromatin through Brd4 correlates with its papillomavirus transcription activation function since JQ1(+), a bromodomain inhibitor that efficiently dissociates E2-Brd4 complexes from chromatin, potently reduces papillomavirus transcription. Our study identifies a specific function of Brd4 in papillomavirus gene transcription and highlights the potential use of bromodomain inhibitors as a method to disrupt the human papillomavirus (HPV) life cycle. PMID:25140737

  10. Coxsackievirus B3-Induced Cellular Protrusions: Structural Characteristics and Functional Competence▿†

    PubMed Central

    Paloheimo, Outi; Ihalainen, Teemu O.; Tauriainen, Sisko; Välilehto, Outi; Kirjavainen, Sanna; Niskanen, Einari A.; Laakkonen, Johanna P.; Hyöty, Heikki; Vihinen-Ranta, Maija

    2011-01-01

    Virus-induced alterations in cell morphology play important roles in the viral life cycle. To examine the intracellular events of coxsackievirus B3 (CVB3) infection, green monkey kidney (GMK) cells were either inoculated with the virus or transfected with the viral RNA. Various microscopic and flow cytometric approaches demonstrated the emergence of CVB3 capsid proteins at 8 h posttransfection, followed by morphological transformation of the cells. The morphological changes included formation of membranous protrusions containing viral capsids, together with microtubules and actin. Translocation of viral capsids into these protrusions was sensitive to cytochalasin D, suggesting the importance of actin in the process. Three-dimensional (3D) live-cell imaging demonstrated frequent contacts between cellular protrusions and adjacent cells. Markedly, in spite of an increase in the cellular viral protein content starting 8 h postinfection, no significant decrease in cell viability or increase in the amount of early apoptotic markers was observed by flow cytometry by 28 h postinfection. Comicroinjection of viral RNA and fluorescent dextran in the presence of neutralizing virus antibody suggested that these protrusions mediated the spread of infection from one cell to another prior to virus-induced cell lysis. Altogether, the CVB3-induced cellular protrusions could function as a hitherto-unknown nonlytic mechanism of cell-to-cell transmission exploited by enteroviruses. PMID:21525342

  11. Hijacking of Host Cellular Functions by an Intracellular Parasite, the Microsporidian Anncaliia algerae

    PubMed Central

    Panek, Johan; El Alaoui, Hicham; Mone, Anne; Urbach, Serge; Demettre, Edith; Texier, Catherine; Brun, Christine; Zanzoni, Andreas; Peyretaillade, Eric; Parisot, Nicolas; Lerat, Emmanuelle; Peyret, Pierre; Delbac, Frederic; Biron, David G.

    2014-01-01

    Intracellular pathogens including bacteria, viruses and protozoa hijack host cell functions to access nutrients and to bypass cellular defenses and immune responses. These strategies have been acquired through selective pressure and allowed pathogens to reach an appropriate cellular niche for their survival and growth. To get new insights on how parasites hijack host cellular functions, we developed a SILAC (Stable Isotope Labeling by Amino Acids in Cell culture) quantitative proteomics workflow. Our study focused on deciphering the cross-talk in a host-parasite association, involving human foreskin fibroblasts (HFF) and the microsporidia Anncaliia algerae, a fungus related parasite with an obligate intracellular lifestyle and a strong host dependency. The host-parasite cross-talk was analyzed at five post-infection times 1, 6, 12 and 24 hours post-infection (hpi) and 8 days post-infection (dpi). A significant up-regulation of four interferon-induced proteins with tetratricopeptide repeats IFIT1, IFIT2, IFIT3 and MX1 was observed at 8 dpi suggesting a type 1 interferon (IFN) host response. Quantitative alteration of host proteins involved in biological functions such as signaling (STAT1, Ras) and reduction of the translation activity (EIF3) confirmed a host type 1 IFN response. Interestingly, the SILAC approach also allowed the detection of 148 A. algerae proteins during the kinetics of infection. Among these proteins many are involved in parasite proliferation, and an over-representation of putative secreted effectors proteins was observed. Finally our survey also suggests that A. algerae could use a transposable element as a lure strategy to escape the host innate immune system. PMID:24967735

  12. Hijacking of host cellular functions by an intracellular parasite, the microsporidian Anncaliia algerae.

    PubMed

    Panek, Johan; El Alaoui, Hicham; Mone, Anne; Urbach, Serge; Demettre, Edith; Texier, Catherine; Brun, Christine; Zanzoni, Andreas; Peyretaillade, Eric; Parisot, Nicolas; Lerat, Emmanuelle; Peyret, Pierre; Delbac, Frederic; Biron, David G

    2014-01-01

    Intracellular pathogens including bacteria, viruses and protozoa hijack host cell functions to access nutrients and to bypass cellular defenses and immune responses. These strategies have been acquired through selective pressure and allowed pathogens to reach an appropriate cellular niche for their survival and growth. To get new insights on how parasites hijack host cellular functions, we developed a SILAC (Stable Isotope Labeling by Amino Acids in Cell culture) quantitative proteomics workflow. Our study focused on deciphering the cross-talk in a host-parasite association, involving human foreskin fibroblasts (HFF) and the microsporidia Anncaliia algerae, a fungus related parasite with an obligate intracellular lifestyle and a strong host dependency. The host-parasite cross-talk was analyzed at five post-infection times 1, 6, 12 and 24 hours post-infection (hpi) and 8 days post-infection (dpi). A significant up-regulation of four interferon-induced proteins with tetratricopeptide repeats IFIT1, IFIT2, IFIT3 and MX1 was observed at 8 dpi suggesting a type 1 interferon (IFN) host response. Quantitative alteration of host proteins involved in biological functions such as signaling (STAT1, Ras) and reduction of the translation activity (EIF3) confirmed a host type 1 IFN response. Interestingly, the SILAC approach also allowed the detection of 148 A. algerae proteins during the kinetics of infection. Among these proteins many are involved in parasite proliferation, and an over-representation of putative secreted effectors proteins was observed. Finally our survey also suggests that A. algerae could use a transposable element as a lure strategy to escape the host innate immune system. PMID:24967735

  13. Comprehensive Interrogation of the Cellular Response to Fluorescent, Detonation and Functionalized Nanodiamonds

    PubMed Central

    Moore, L.; Grobárová, V.; Shen, H.; Man, H. B.; Míčová, J.; Ledvina, M.; Štursa, J.; Nesladek, M.

    2015-01-01

    Nanodiamonds (NDs) are versatile nanoparticles that are currently being investigated for a variety of applications in drug delivery, biomedical imaging and nanoscale sensing. Although initial studies indicate that these small gems are biocompatible, there is a great deal of variability in synthesis methods and surface functionalization that has yet to be evaluated. Here we present a comprehensive analysis of the cellular compatibility of an array of nanodiamond subtypes and surface functionalization strategies. These results demonstrate that NDs are well tolerated by multiple cell types at both functional and gene expression levels. In addition, ND-mediated delivery of daunorubicin is less toxic to multiple cell types than treatment with daunorubicin alone, demonstrating the ability of the ND agent to improve drug tolerance and decrease therapeutic toxicity. Overall, the results here indicate that ND biocompatibility serves as a promising foundation for continued preclinical investigation. PMID:25037888

  14. Comprehensive interrogation of the cellular response to fluorescent, detonation and functionalized nanodiamonds.

    PubMed

    Moore, Laura; Grobárová, Valéria; Shen, Helen; Man, Han Bin; Míčová, Júlia; Ledvina, Miroslav; Štursa, Jan; Nesladek, Milos; Fišerová, Anna; Ho, Dean

    2014-10-21

    Nanodiamonds (NDs) are versatile nanoparticles that are currently being investigated for a variety of applications in drug delivery, biomedical imaging and nanoscale sensing. Although initial studies indicate that these small gems are biocompatible, there is a great deal of variability in synthesis methods and surface functionalization that has yet to be evaluated. Here we present a comprehensive analysis of the cellular compatibility of an array of nanodiamond subtypes and surface functionalization strategies. These results demonstrate that NDs are well tolerated by multiple cell types at both functional and gene expression levels. In addition, ND-mediated delivery of daunorubicin is less toxic to multiple cell types than treatment with daunorubicin alone, thus demonstrating the ability of the ND agent to improve drug tolerance and decrease therapeutic toxicity. Overall, the results here indicate that ND biocompatibility serves as a promising foundation for continued preclinical investigation. PMID:25037888

  15. Comprehensive interrogation of the cellular response to fluorescent, detonation and functionalized nanodiamonds

    NASA Astrophysics Data System (ADS)

    Moore, Laura; Grobárová, Valéria; Shen, Helen; Man, Han Bin; Míčová, Júlia; Ledvina, Miroslav; Štursa, Jan; Nesladek, Milos; Fišerová, Anna; Ho, Dean

    2014-09-01

    Nanodiamonds (NDs) are versatile nanoparticles that are currently being investigated for a variety of applications in drug delivery, biomedical imaging and nanoscale sensing. Although initial studies indicate that these small gems are biocompatible, there is a great deal of variability in synthesis methods and surface functionalization that has yet to be evaluated. Here we present a comprehensive analysis of the cellular compatibility of an array of nanodiamond subtypes and surface functionalization strategies. These results demonstrate that NDs are well tolerated by multiple cell types at both functional and gene expression levels. In addition, ND-mediated delivery of daunorubicin is less toxic to multiple cell types than treatment with daunorubicin alone, thus demonstrating the ability of the ND agent to improve drug tolerance and decrease therapeutic toxicity. Overall, the results here indicate that ND biocompatibility serves as a promising foundation for continued preclinical investigation.

  16. Functional recognition imaging using artificial neural networks: applications to rapid cellular identification via broadband electromechanical response

    NASA Astrophysics Data System (ADS)

    Nikiforov, M. P.; Reukov, V. V.; Thompson, G. L.; Vertegel, A. A.; Guo, S.; Kalinin, S. V.; Jesse, S.

    2009-10-01

    Functional recognition imaging in scanning probe microscopy (SPM) using artificial neural network identification is demonstrated. This approach utilizes statistical analysis of complex SPM responses at a single spatial location to identify the target behavior, which is reminiscent of associative thinking in the human brain, obviating the need for analytical models. We demonstrate, as an example of recognition imaging, rapid identification of cellular organisms using the difference in electromechanical activity over a broad frequency range. Single-pixel identification of model Micrococcus lysodeikticus and Pseudomonas fluorescens bacteria is achieved, demonstrating the viability of the method.

  17. A new design for reconfigurable XOR function based on cellular neural networks

    NASA Astrophysics Data System (ADS)

    Liu, Yanyi; Liu, Wenbo

    2014-10-01

    We have described a new method to construct the reconfigurable XOR logic circuit by using the modification of the standard uncoupled cellular neural network (CNN) cells. The modification of the cell is easier to implement in engineering applications. The scheme proposed in this paper, using the modification of standard uncoupled CNN cells, allows less hardware consumption in comparison to the utilisation of chaos computing system or harnessing piecewise-linear systems. The template parameters of the modified cell have been discussed, and the physical circuit implementing the reconfigurable two-input and three-input XOR function has also been presented.

  18. Functional significance of preserved affect recognition in schizophrenia

    PubMed Central

    Fiszdon, Joanna M.; Johannesen, Jason K.

    2009-01-01

    Affect recognition (AR) is a core component of social information processing, thus may be critical to understanding social behavior and functioning in broader aspects of daily living. Deficits in AR are well documented in schizophrenia, however, there is also evidence that many individuals with schizophrenia perform AR tasks at near-normal levels. In the current study, we sought to evaluate the functional significance of AR deficits in schizophrenia by comparing subgroups with normal-range and impaired AR performance on proxy and interviewer-rated measures of real-world functioning. Schizophrenia outpatients were classified as normal-range (N=17) and impaired (N=31) based on a logistic cut point in the sample distribution of BLERT scores, referenced to a normative sample of healthy control subjects (N=56). The derived schizophrenia subgroups were then compared on proxy (UCSD, UPSA, SSPA, MMAA) and interviewer-rated (QLS, ILSS) measures of functioning, as well as battery of neurocognitive tests. Initial analyses indicated superior MMAA and QLS performance in the near-normal AR subgroup. Covariate analyses indicated that group differences in neurocognition fully mediated the observed associations between AR and MMAA and attenuated the observed relationships between AR classification and QLS. These results support three main conclusions. First, AR, like many other domains of psychopathology studied in schizophrenia, is preserved in select subgroups. Second, there is a positive relationship between AR performance and functional outcome measures. Third, neurocognition appears to mediate the relationship between AR and measures of functioning. PMID:20202689

  19. Factors affecting sexual function in menopause: A review article.

    PubMed

    Nazarpour, Soheila; Simbar, Masoumeh; Tehrani, Fahimeh Ramezani

    2016-08-01

    This study aimed to systematically review the articles on factors affecting sexual function during menopause. Searching articles indexed in Pubmed, Science Direct, Iranmedex, EMBASE, Scopus, and Scientific Information Database databases, a total number of 42 studies published between 2003 and 2013 were selected. Age, estrogen deficiency, type of menopause, chronic medical problems, partner's sex problems, severity of menopause symptoms, dystocia history, and health status were the physical factors influencing sexual function of menopausal women. There were conflicting results regarding the amount of androgens, hormonal therapy, exercise/physical activity, and obstetric history. In the mental-emotional area, all studies confirmed the impact of depression and anxiety. Social factors, including smoking, alcohol consumption, the quality of relationship with husband, partner's loyalty, sexual knowledge, access to health care, a history of divorce or the death of a husband, living apart from a spouse, and a negative understanding of women's health were found to affect sexual function; however, there were conflicting results regarding the effects of education, occupation, socioeconomic status, marital duration, and frequency of sexual intercourse. PMID:27590367

  20. Surface charge and cellular processing of covalently functionalized multiwall carbon nanotubes determine pulmonary toxicity.

    PubMed

    Li, Ruibin; Wang, Xiang; Ji, Zhaoxia; Sun, Bingbing; Zhang, Haiyuan; Chang, Chong Hyun; Lin, Sijie; Meng, Huan; Liao, Yu-Pei; Wang, Meiying; Li, Zongxi; Hwang, Angela A; Song, Tze-Bin; Xu, Run; Yang, Yang; Zink, Jeffrey I; Nel, André E; Xia, Tian

    2013-03-26

    Functionalized carbon nanotubes (f-CNTs) are being produced in increased volume because of the ease of dispersion and maintenance of the pristine material physicochemical properties when used in composite materials as well as for other commercial applications. However, the potential adverse effects of f-CNTs have not been quantitatively or systematically explored. In this study, we used a library of covalently functionalized multiwall carbon nanotubes (f-MWCNTs), established from the same starting material, to assess the impact of surface charge in a predictive toxicological model that relates the tubes' pro-inflammatory and pro-fibrogenic effects at cellular level to the development of pulmonary fibrosis. Carboxylate (COOH), polyethylene glycol (PEG), amine (NH2), sidewall amine (sw-NH2), and polyetherimide (PEI)-modified MWCNTs were successfully established from raw or as-prepared (AP-) MWCNTs and comprehensively characterized by TEM, XPS, FTIR, and DLS to obtain information about morphology, length, degree of functionalization, hydrodynamic size, and surface charge. Cellular screening in BEAS-2B and THP-1 cells showed that, compared to AP-MWCNTs, anionic functionalization (COOH and PEG) decreased the production of pro-fibrogenic cytokines and growth factors (including IL-1β, TGF-β1, and PDGF-AA), while neutral and weak cationic functionalization (NH2 and sw-NH2) showed intermediary effects. In contrast, the strongly cationic PEI-functionalized tubes induced robust biological effects. These differences could be attributed to differences in cellular uptake and NLRP3 inflammasome activation, which depends on the propensity toward lysosomal damage and cathepsin B release in macrophages. Moreover, the in vitro hazard ranking was validated by the pro-fibrogenic potential of the tubes in vivo. Compared to pristine MWCNTs, strong cationic PEI-MWCNTs induced significant lung fibrosis, while carboxylation significantly decreased the extent of pulmonary fibrosis. These

  1. The Surface Charge and Cellular Processing of Covalently Functionalized Multiwall Carbon Nanotubes Determine Pulmonary Toxicity

    PubMed Central

    Li, Ruibin; Wang, Xiang; Ji, Zhaoxia; Sun, Bingbing; Zhang, Haiyuan; Chang, Chong Hyun; Lin, Sijie; Meng, Huan; Liao, Yu-Pei; Wang, Meiying; Li, Zongxi; Hwang, Angela; Song, Tze-Bin; Xu, Run; Yang, Yang; Zink, Jeffrey I.; Nel, André E.; Xia, Tian

    2014-01-01

    Functionalized carbon nanotubes (f-CNTs) are being produced in increased volume because of the ease of dispersion and maintenance of the pristine material physicochemical properties when used in composite materials as well as for other commercial applications. However, the potential adverse effects of f-CNTs have not been quantitatively or systematically explored, and in this study we used a library of covalently functionalized multiwall carbon nanotubes (f-MWCNTs), established from the same starting material, to assess the impact of surface charge in a predictive toxicological model that relates the tubes’ pro-inflammatory and pro-fibrogenic effects at cellular level to the development of pulmonary fibrosis. Carboxylated (COOH), polyethylene glycol (PEG), amine (NH2), sidewall amine (sw-NH2) and polyetherimide (PEI) modified MWCNTs were successfully established from raw or as-prepared (AP-) MWCNTs, and comprehensively characterized by TEM, XPS, FTIR and DLS to obtain information about morphology, length, degree of functionalization, hydrodynamic size and surface charge. Cellular screening in BEAS-2B and THP-1 cells showed that, compared to AP-MWCNTs, anionic functionalization (COOH and PEG) decreased the production of pro-fibrogenic cytokines and growth factors (including IL-1β, TGF-β1 and PDGF-AA), while neutral and weak cationic functionalization (NH2 and sw-NH2) showed intermediary effects. In contrast, the strongly cationic PEI-functionalized tubes induced robust biological effects. These differences could be attributed to differences in cellular uptake and NLRP3 inflammasome activation, which depends on the propensity towards lysosomal damage and cathepsin B release in macrophages. Moreover, the in vitro hazard ranking was validated by the pro-fibrogenic potential of the tubes in vivo. Compared to pristine MWCNTs, strong cationic PEIMWCNTs induced significant lung fibrosis, while carboxylation significantly decreased the extent of pulmonary fibrosis

  2. Cellular Functions and X-ray Structure of Anthrolysin O, a Cholesterol-dependent Cytolysin Secreted by Bacillus anthracis

    SciTech Connect

    Bourdeau, Raymond W.; Malito, Enrico; Chenal, Alexandre; Bishop, Brian L.; Musch, Mark W.; Villereal, Mitch L.; Chang, Eugene B.; Mosser, Elise M.; Rest, Richard F.; Tang, Wei-Jen

    2009-06-02

    Anthrolysin O (ALO) is a pore-forming, cholesterol-dependent cytolysin (CDC) secreted by Bacillus anthracis, the etiologic agent for anthrax. Growing evidence suggests the involvement of ALO in anthrax pathogenesis. Here, we show that the apical application of ALO decreases the barrier function of human polarized epithelial cells as well as increases intracellular calcium and the internalization of the tight junction protein occludin. Using pharmacological agents, we also found that barrier function disruption requires increased intracellular calcium and protein degradation. We also report a crystal structure of the soluble state of ALO. Based on our analytical ultracentrifugation and light scattering studies, ALO exists as a monomer. Our ALO structure provides the molecular basis as to how ALO is locked in a monomeric state, in contrast to other CDCs that undergo antiparallel dimerization or higher order oligomerization in solution. ALO has four domains and is globally similar to perfringolysin O (PFO) and intermedilysin (ILY), yet the highly conserved undecapeptide region in domain 4 (D4) adopts a completely different conformation in all three CDCs. Consistent with the differences within D4 and at the D2-D4 interface, we found that ALO D4 plays a key role in affecting the barrier function of C2BBE cells, whereas PFO domain 4 cannot substitute for this role. Novel structural elements and unique cellular functions of ALO revealed by our studies provide new insight into the molecular basis for the diverse nature of the CDC family.

  3. Microbial composition affects the functioning of estuarine sediments

    PubMed Central

    Reed, Heather E; Martiny, Jennifer BH

    2013-01-01

    Although microorganisms largely drive many ecosystem processes, the relationship between microbial composition and their functioning remains unclear. To tease apart the effects of composition and the environment directly, microbial composition must be manipulated and maintained, ideally in a natural ecosystem. In this study, we aimed to test whether variability in microbial composition affects functional processes in a field setting, by reciprocally transplanting riverbed sediments between low- and high-salinity locations along the Nonesuch River (Maine, USA). We placed the sediments into microbial ‘cages' to prevent the migration of microorganisms, while allowing the sediments to experience the abiotic conditions of the surroundings. We performed two experiments, short- (1 week) and long-term (7 weeks) reciprocal transplants, after which we assayed a variety of functional processes in the cages. In both experiments, we examined the composition of bacteria generally (targeting the 16S rDNA gene) and sulfate-reducing bacteria (SRB) specifically (targeting the dsrAB gene) using terminal restriction fragment length polymorphism (T-RFLP). In the short-term experiment, sediment processes (CO2 production, CH4 flux, nitrification and enzyme activities) depended on both the sediment's origin (reflecting differences in microbial composition between salt and freshwater sediments) and the surrounding environment. In the long-term experiment, general bacterial composition (but not SRB composition) shifted in response to their new environment, and this composition was significantly correlated with sediment functioning. Further, sediment origin had a diminished effect, relative to the short-term experiment, on sediment processes. Overall, this study provides direct evidence that microbial composition directly affects functional processes in these sediments. PMID:23235294

  4. CELLULAR BIOAVAILABILITY OF NATURAL HORMONES AND ENVIRONMENTAL CONTAMINANTS AS A FUNCTION OF SERUM AND CYTOSOLIC BINDING FACTORS

    EPA Science Inventory

    Environmental contaminants have been reported to function as hormone mimics in various wildlife species. To investigate a potential mechanism for the interaction of contaminants with the endocrine system, we evaluated the cellular bioavailability of numerous chemicals. Hormone bi...

  5. Cardiac function in an endothermic fish: cellular mechanisms for overcoming acute thermal challenges during diving.

    PubMed

    Shiels, H A; Galli, G L J; Block, B A

    2015-02-01

    Understanding the physiology of vertebrate thermal tolerance is critical for predicting how animals respond to climate change. Pacific bluefin tuna experience a wide range of ambient sea temperatures and occupy the largest geographical niche of all tunas. Their capacity to endure thermal challenge is due in part to enhanced expression and activity of key proteins involved in cardiac excitation-contraction coupling, which improve cardiomyocyte function and whole animal performance during temperature change. To define the cellular mechanisms that enable bluefin tuna hearts to function during acute temperature change, we investigated the performance of freshly isolated ventricular myocytes using confocal microscopy and electrophysiology. We demonstrate that acute cooling and warming (between 8 and 28°C) modulates the excitability of the cardiomyocyte by altering the action potential (AP) duration and the amplitude and kinetics of the cellular Ca(2+) transient. We then explored the interactions between temperature, adrenergic stimulation and contraction frequency, and show that when these stressors are combined in a physiologically relevant way, they alter AP characteristics to stabilize excitation-contraction coupling across an acute 20°C temperature range. This allows the tuna heart to maintain consistent contraction and relaxation cycles during acute thermal challenges. We hypothesize that this cardiac capacity plays a key role in the bluefin tunas' niche expansion across a broad thermal and geographical range. PMID:25540278

  6. Coffea arabica Seed Extract Stimulate the Cellular Immune Function and Cyclophosphamide-induced Immunosuppression in Mice

    PubMed Central

    Rafiul Haque, Mohammad; Ansari, Shahid Hussain; Rashikh, Azhar

    2013-01-01

    In this study, we investigate the immunostimulatory effects of alcoholic extract of the coffee seed on cell-mediated immune response and cyclophosphamide-induced (CP) immunosuppressed mice. The assessment of cellular immune function was carried out by the measurement of delayed-type hypersensitivity (DTH) response. According to the literature survey, cyclophosphamide has only suppressing effect on the lymphoid organ, white blood cell (WBC) and other parts of humoral immunity. Humoral immunity was assessed by the hemagglutination antibody titre. Mice were treated with three doses of extract (50, 150 and 250 mg/Kg body weight per os). Relative organ weight and WBC counts were also studied in these animals. At doses of 50 and 150, a significant increase (p < 0.05) in relative organ weight of spleen and thymus was observed but there was no effect on kidney and liver weights. WBC counts was also increased significantly (p < 0.001) in all doses of the plant extract. Coffea arabica extract elicited a significant (p < 0.001) increase in the DTH response at doses of 50 and 150 mg/Kg, but the change at higher dose of 250 mg/Kg was not statistically significant. In the HT test, plant extract also showed modulatory effect at all doses groups. Over all, coffee seed showed the stimulatory effect on cellular immune function and cyclophosphamide induced immunosuppression in mice. PMID:24250577

  7. Functional characterization of novel genotypes and cellular oxidative stress studies in propionic acidemia.

    PubMed

    Gallego-Villar, Lorena; Pérez-Cerdá, Celia; Pérez, Belén; Abia, David; Ugarte, Magdalena; Richard, Eva; Desviat, Lourdes R

    2013-09-01

    Propionic acidemia (PA), caused by a deficiency of the mitochondrial biotin dependent enzyme propionyl-CoA carboxylase (PCC) is one of the most frequent organic acidurias in humans. PA is caused by mutations in either the PCCA or PCCB genes encoding the α- and β-subunits of the PCC enzyme which are assembled as an α6β6 dodecamer. In this study we have investigated the molecular basis of the defect in ten fibroblast samples from PA patients. Using homology modeling with the recently solved crystal structure of the PCC holoenzyme and a eukaryotic expression system we have analyzed the structural and functional effect of novel point mutations, also revealing a novel splice defect by minigene analysis. In addition, we have investigated the contribution of oxidative stress to cellular damage measuring reactive oxygen species (ROS) levels and apoptosis parameters in patient fibroblasts, as recent studies point to a secondary mitochondrial dysfunction as pathophysiological mechanism in this disorder. The results show an increase in intracellular ROS content compared to controls, correlating with the activation of the JNK and p38 signaling pathways. Highest ROS levels were present in cells harboring functionally null mutations, including one severe missense mutation. This work provides molecular insight into the pathogenicity of PA variants and indicates that oxidative stress may be a major contributing factor to the cellular damage, supporting the proposal of antioxidant strategies as novel supplementary therapy in this rare disease. PMID:23053474

  8. Cardiac function in an endothermic fish: cellular mechanisms for overcoming acute thermal challenges during diving

    PubMed Central

    Shiels, H. A.; Galli, G. L. J.; Block, B. A.

    2015-01-01

    Understanding the physiology of vertebrate thermal tolerance is critical for predicting how animals respond to climate change. Pacific bluefin tuna experience a wide range of ambient sea temperatures and occupy the largest geographical niche of all tunas. Their capacity to endure thermal challenge is due in part to enhanced expression and activity of key proteins involved in cardiac excitation–contraction coupling, which improve cardiomyocyte function and whole animal performance during temperature change. To define the cellular mechanisms that enable bluefin tuna hearts to function during acute temperature change, we investigated the performance of freshly isolated ventricular myocytes using confocal microscopy and electrophysiology. We demonstrate that acute cooling and warming (between 8 and 28°C) modulates the excitability of the cardiomyocyte by altering the action potential (AP) duration and the amplitude and kinetics of the cellular Ca2+ transient. We then explored the interactions between temperature, adrenergic stimulation and contraction frequency, and show that when these stressors are combined in a physiologically relevant way, they alter AP characteristics to stabilize excitation–contraction coupling across an acute 20°C temperature range. This allows the tuna heart to maintain consistent contraction and relaxation cycles during acute thermal challenges. We hypothesize that this cardiac capacity plays a key role in the bluefin tunas' niche expansion across a broad thermal and geographical range. PMID:25540278

  9. Molecular, Cellular and Functional Effects of Radiation-Induced Brain Injury: A Review

    PubMed Central

    Balentova, Sona; Adamkov, Marian

    2015-01-01

    Radiation therapy is the most effective non-surgical treatment of primary brain tumors and metastases. Preclinical studies have provided valuable insights into pathogenesis of radiation-induced injury to the central nervous system. Radiation-induced brain injury can damage neuronal, glial and vascular compartments of the brain and may lead to molecular, cellular and functional changes. Given its central role in memory and adult neurogenesis, the majority of studies have focused on the hippocampus. These findings suggested that hippocampal avoidance in cranial radiotherapy prevents radiation-induced cognitive impairment of patients. However, multiple rodent studies have shown that this problem is more complex. As the radiation-induced cognitive impairment reflects hippocampal and non-hippocampal compartments, it is of critical importance to investigate molecular, cellular and functional modifications in various brain regions as well as their integration at clinically relevant doses and schedules. We here provide a literature overview, including our previously published results, in order to support the translation of preclinical findings to clinical practice, and improve the physical and mental status of patients with brain tumors. PMID:26610477

  10. Molecular, Cellular and Functional Effects of Radiation-Induced Brain Injury: A Review.

    PubMed

    Balentova, Sona; Adamkov, Marian

    2015-01-01

    Radiation therapy is the most effective non-surgical treatment of primary brain tumors and metastases. Preclinical studies have provided valuable insights into pathogenesis of radiation-induced injury to the central nervous system. Radiation-induced brain injury can damage neuronal, glial and vascular compartments of the brain and may lead to molecular, cellular and functional changes. Given its central role in memory and adult neurogenesis, the majority of studies have focused on the hippocampus. These findings suggested that hippocampal avoidance in cranial radiotherapy prevents radiation-induced cognitive impairment of patients. However, multiple rodent studies have shown that this problem is more complex. As the radiation-induced cognitive impairment reflects hippocampal and non-hippocampal compartments, it is of critical importance to investigate molecular, cellular and functional modifications in various brain regions as well as their integration at clinically relevant doses and schedules. We here provide a literature overview, including our previously published results, in order to support the translation of preclinical findings to clinical practice, and improve the physical and mental status of patients with brain tumors. PMID:26610477

  11. S-glutathionylation uncouples eNOS and regulates its cellular and vascular function

    PubMed Central

    Chen, Chun-An; Wang, Tse-Yao; Varadharaj, Saradhadevi; Reyes, Levy A.; Hemann, Craig; Hassan Talukder, M. A.; Chen, Yeong-Renn; Druhan, Lawrence J.; Zweier, Jay L.

    2012-01-01

    Endothelial nitric oxide synthase (eNOS) is critical in the regulation of vascular function, and can generate both nitric oxide (NO) and superoxide (O2•−), which are key mediators of cellular signalling. In the presence of Ca2+/calmodulin, eNOS produces NO, endothelial-derived relaxing factor, from L-arginine (L-Arg) by means of electron transfer from NADPH through a flavin containing reductase domain to oxygen bound at the haem of an oxygenase domain, which also contains binding sites for tetrahydrobiopterin (BH4) and L-Arg1–3. In the absence of BH4, NO synthesis is abrogated and instead O2•− is generated4–7. While NOS dysfunction occurs in diseases with redox stress, BH4 repletion only partly restores NOS activity and NOS-dependent vasodilation7. This suggests that there is an as yet unidentified redox-regulated mechanism controlling NOS function. Protein thiols can undergo S-glutathionylation, a reversible protein modification involved in cellular signalling and adaptation8,9. Under oxidative stress, S-glutathionylation occurs through thiol–disulphide exchange with oxidized glutathione or reaction of oxidant-induced protein thiyl radicals with reduced glutathione10,11. Cysteine residues are critical for the maintenance of eNOS function12,13; we therefore speculated that oxidative stress could alter eNOS activity through S-glutathionylation. Here we show that S-glutathionylation of eNOS reversibly decreases NOS activity with an increase in O2•− generation primarily from the reductase, in which two highly conserved cysteine residues are identified as sites of S-glutathionylation and found to be critical for redox-regulation of eNOS function. We show that eNOS S-glutathionylation in endothelial cells, with loss of NO and gain of O2•− generation, is associated with impaired endothelium-dependent vasodilation. In hypertensive vessels, eNOS S-glutathionylation is increased with impaired endothelium-dependent vasodilation that is restored by thiol

  12. Neurotransmitter Specific, Cellular-Resolution Functional Brain Mapping Using Receptor Coated Nanoparticles: Assessment of the Possibility

    PubMed Central

    Forati, Ebrahim; Sabouni, Abas; Ray, Supriyo; Head, Brian; Schoen, Christian; Sievenpiper, Dan

    2015-01-01

    Receptor coated resonant nanoparticles and quantum dots are proposed to provide a cellular-level resolution image of neural activities inside the brain. The functionalized nanoparticles and quantum dots in this approach will selectively bind to different neurotransmitters in the extra-synaptic regions of neurons. This allows us to detect neural activities in real time by monitoring the nanoparticles and quantum dots optically. Gold nanoparticles (GNPs) with two different geometries (sphere and rod) and quantum dots (QDs) with different sizes were studied along with three different neurotransmitters: dopamine, gamma-Aminobutyric acid (GABA), and glycine. The absorption/emission spectra of GNPs and QDs before and after binding of neurotransmitters and their corresponding receptors are reported. The results using QDs and nanorods with diameter 25nm and aspect rations larger than three were promising for the development of the proposed functional brain mapping approach. PMID:26717196

  13. The functions of cardiolipin in cellular metabolism-potential modifiers of the Barth syndrome phenotype.

    PubMed

    Raja, Vaishnavi; Greenberg, Miriam L

    2014-04-01

    The phospholipid cardiolipin (CL) plays a role in many cellular functions and signaling pathways both inside and outside of mitochondria. This review focuses on the role of CL in energy metabolism. Many reactions of electron transport and oxidative phosphorylation, the transport of metabolites required for these processes, and the stabilization of electron transport chain supercomplexes require CL. Recent studies indicate that CL is required for the synthesis of iron-sulfur (Fe-S) co-factors, which are essential for numerous metabolic pathways. Activation of carnitine shuttle enzymes that are required for fatty acid metabolism is CL dependent. The presence of substantial amounts of CL in the peroxisomal membrane suggests that CL may be required for peroxisomal functions. Understanding the role of CL in energy metabolism may identify physiological modifiers that exacerbate the loss of CL and underlie the variation in symptoms observed in Barth syndrome, a genetic disorder of CL metabolism. PMID:24445246

  14. Mevalonate availability affects human and rat resistance vessel function.

    PubMed Central

    Roullet, J B; Xue, H; Roullet, C M; Fletcher, W S; Cipolla, M J; Harker, C T; McCarron, D A

    1995-01-01

    Previous data in rat conductance vessels indicated that cellular mevalonate contributes to vascular tone and systemic blood pressure control. Using exogenous mevalonate (M) or lovastatin, a 3-hydroxy-3-methyl-glutaryl CoA (HMG-CoA) reductase inhibitor (L), we characterized the role of mevalonate availability in resistance artery function, both in experimental animals and humans. Rat mesenteric artery resistance vessels (MARV, n = 9) were incubated for 48 h with either L, M, L + M, or vehicle (V) and tested for reactivity to NE, serotonin, acetylcholine, atrial natriuretic peptide, and sodium nitroprusside (SNP). Lovastatin increased sensitivity to NE (P < 0.03) and serotonin (P < 0.003), and significantly impaired the response to all three vasodilators. These effects were reversed by co-incubation with mevalonate. Mevalonate alone had no effect. In separate experiments, intravascular free Ca2+ concentration (ivfCa2+) was determined in fura-2AM loaded MARV. Basal ivfCa2+ was increased after a 48-h exposure to L (52.7 +/- 4.6 nM, L, vs. 29.7 +/- 2.4 nM, V, n = 12, P < 0.003), as were ivfCa2+ levels following stimulation with low (100 nM) NE concentrations. Similar ivfCa2+ concentrations were achieved during maximum contraction with NE (10 mM) in both groups. Human resistance arteries of human adipose tissue were also studied. Lovastatin increased the sensitivity to NE (ED50 = 372 +/- 56 nM, V, and 99 +/- 33 nM, L, P < 0.001) and significantly decreased the relaxation to acetylcholine and SNP of human vessels. We conclude that mevalonate availability directly contribute to resistance vessel function and vascular signal transduction systems in both experimental animals and humans. The study calls for the identification of non-sterol, mevalonate-derived vasoactive metabolites, and suggests that disorders of the mevalonate pathway can alter vascular tone and cause hypertension. PMID:7615793

  15. Development of mechano-responsive polymeric scaffolds using functionalized silica nano-fillers for the control of cellular functions.

    PubMed

    Griffin, Michelle; Nayyer, Leila; Butler, Peter E; Palgrave, Robert G; Seifalian, Alexander M; Kalaskar, Deepak M

    2016-08-01

    We demonstrate an efficient method to produce mechano-responsive polymeric scaffolds which can alter cellular functions using two different functionalized (OH and NH2) silica nano-fillers. Fumed silica-hydroxyl and fumed silica-amine nano-fillers were mixed with a biocompatible polymer (POSS-PCU) at various wt% to produce scaffolds. XPS and mechanical testing demonstrate that bulk mechanical properties are modified without changing the scaffold's surface chemistry. Mechanical testing showed significant change in bulk properties of POSS-PCU scaffolds with an addition of silica nanofillers as low as 1% (P<0.01). Scaffolds modified with NH2 silica showed significantly higher bulk mechanical properties compared to the one modified with the OH group. Enhanced cell adhesion, proliferation and collagen production over 14days were observed on scaffolds with higher bulk mechanical properties (NH2) compared to those with lower ones (unmodified and OH modified) (P<0.05) during in vitro analysis. This study provides an effective method of manufacturing mechano-responsive polymeric scaffolds, which can help to customize cellular responses for biomaterial applications. PMID:27013128

  16. Molecular design and nanoparticle-mediated intracellular delivery of functional proteins to target cellular pathways

    NASA Astrophysics Data System (ADS)

    Shah, Dhiral Ashwin

    Intracellular delivery of specific proteins and peptides represents a novel method to influence stem cells for gain-of-function and loss-of-function. Signaling control is vital in stem cells, wherein intricate control of and interplay among critical pathways directs the fate of these cells into either self-renewal or differentiation. The most common route to manipulate cellular function involves the introduction of genetic material such as full-length genes and shRNA into the cell to generate (or prevent formation of) the target protein, and thereby ultimately alter cell function. However, viral-mediated gene delivery may result in relatively slow expression of proteins and prevalence of oncogene insertion into the cell, which can alter cell function in an unpredictable fashion, and non-viral delivery may lead to low efficiency of genetic delivery. For example, the latter case plagues the generation of induced pluripotent stem cells (iPSCs) and hinders their use for in vivo applications. Alternatively, introducing proteins into cells that specifically recognize and influence target proteins, can result in immediate deactivation or activation of key signaling pathways within the cell. In this work, we demonstrate the cellular delivery of functional proteins attached to hydrophobically modified silica (SiNP) nanoparticles to manipulate specifically targeted cell signaling proteins. In the Wnt signaling pathway, we have targeted the phosphorylation activity of glycogen synthase kinase-3beta (GSK-3beta) by designing a chimeric protein and delivering it in neural stem cells. Confocal imaging indicates that the SiNP-chimeric protein conjugates were efficiently delivered to the cytosol of human embryonic kidney cells and rat neural stem cells, presumably via endocytosis. This uptake impacted the Wnt signaling cascade, indicated by the elevation of beta-catenin levels, and increased transcription of Wnt target genes, such as c-MYC. The results presented here suggest that

  17. How does temperature affect the function of tissue macrophages?

    NASA Astrophysics Data System (ADS)

    Lee, Chen-Ting; Repasky, Elizabeth A.

    2011-03-01

    Macrophages create a major danger signal following injury or infection and upon activation release pro-inflammatory cytokines, which in turn help to generate febrile conditions. Thus, like other cells of the body, tissue macrophages are often exposed to naturally occurring elevations in tissue temperature during inflammation and fever. However, whether macrophages sense and respond to temperature changes in a specific manner which modulates their function is still not clear. In this brief review, we highlight recent studies which have analyzed the effects of temperatures on macrophage function, and summarize the possible underlying molecular mechanisms which have been identified. Mild, physiological range hyperthermia has been shown to have both pro- and anti-inflammatory roles in regulating macrophage inflammatory cytokine production and at the meeting presentation, we will show new data demonstrating that hyperthermia can indeed exert both positive and negative signals to macrophages. While some thermal effects are correlated with the induction of heat shock factors/heat shock proteins, overall it is not clear how mild hyperthermia can exert both pro- and anti-inflammatory functions. We also summarize data which shows that hyperthermia can affect other macrophage effector functions, including the anti-tumor cytotoxicity. Overall, these studies may help us to better understand the immunological role of tissue temperature and may provide important information needed to maximize the application of heat in the treatment of various diseases including cancer.

  18. Can the hydrophilicity of functional monomers affect chemical interaction?

    PubMed

    Feitosa, V P; Ogliari, F A; Van Meerbeek, B; Watson, T F; Yoshihara, K; Ogliari, A O; Sinhoreti, M A; Correr, A B; Cama, G; Sauro, S

    2014-02-01

    The number of carbon atoms and/or ester/polyether groups in spacer chains may influence the interaction of functional monomers with calcium and dentin. The present study assessed the chemical interaction and bond strength of 5 standard-synthesized phosphoric-acid ester functional monomers with different spacer chain characteristics, by atomic absorption spectroscopy (AAS), ATR-FTIR, thin-film x-ray diffraction (TF-XRD), scanning electron microscopy (SEM), and microtensile bond strength (μTBS). The tested functional monomers were 2-MEP (two-carbon spacer chain), 10-MDP (10-carbon), 12-MDDP (12-carbon), MTEP (more hydrophilic polyether spacer chain), and CAP-P (intermediate hydrophilicity ester spacer). The intensity of monomer-calcium salt formation measured by AAS differed in the order of 12-MDDP=10-MDP>CAP-P>MTEP>2-MEP. FTIR and SEM analyses of monomer-treated dentin surfaces showed resistance to rinsing for all monomer-dentin bonds, except with 2-MEP. TF-XRD confirmed the weaker interaction of 2-MEP. Highest µTBS was observed for 12-MDDP and 10-MDP. A shorter spacer chain (2-MEP) of phosphate functional monomers induced formation of unstable monomer-calcium salts, and lower chemical interaction and dentin bond strength. The presence of ester or ether groups within longer spacer carbon chains (CAP-P and MTEP) may affect the hydrophilicity, μTBS, and also the formation of monomer-calcium salts. PMID:24284259

  19. Biomaterial design for specific cellular interactions: Role of surface functionalization and geometric features

    NASA Astrophysics Data System (ADS)

    Kolhar, Poornima

    The areas of drug delivery and tissue engineering have experienced extraordinary growth in recent years with the application of engineering principles and their potential to support and improve the field of medicine. The tremendous progress in nanotechnology and biotechnology has lead to this explosion of research and development in biomedical applications. Biomaterials can now be engineered at a nanoscale and their specific interactions with the biological tissues can be modulated. Various design parameters are being established and researched for design of drug-delivery carriers and scaffolds to be implanted into humans. Nanoparticles made from versatile biomaterial can deliver both small-molecule drugs and various classes of bio-macromolecules, such as proteins and oligonucleotides. Similarly in the field of tissue engineering, current approaches emphasize nanoscale control of cell behavior by mimicking the natural extracellular matrix (ECM) unlike, traditional scaffolds. Drug delivery and tissue engineering are closely connected fields and both of these applications require materials with exceptional physical, chemical, biological, and biomechanical properties to provide superior therapy. In the current study the surface functionalization and the geometric features of the biomaterials has been explored. In particular, a synthetic surface for culture of human embryonic stem cells has been developed, demonstrating the importance of surface functionalization in maintaining the pluripotency of hESCs. In the second study, the geometric features of the drug delivery carriers are investigated and the polymeric nanoneedles mediated cellular permeabilization and direct cytoplasmic delivery is reported. In the third study, the combined effect of surface functionalization and geometric modification of carriers for vascular targeting is enunciated. These studies illustrate how the biomaterials can be designed to achieve various cellular behaviors and control the

  20. Structural and functional characterization of recombinant human cellular retinaldehyde-binding protein.

    PubMed Central

    Crabb, J. W.; Carlson, A.; Chen, Y.; Goldflam, S.; Intres, R.; West, K. A.; Hulmes, J. D.; Kapron, J. T.; Luck, L. A.; Horwitz, J.; Bok, D.

    1998-01-01

    Cellular retinaldehyde-binding protein (CRALBP) is abundant in the retinal pigment epithelium (RPE) and Müller cells of the retina where it is thought to function in retinoid metabolism and visual pigment regeneration. The protein carries 11-cis-retinal and/or 11-cis-retinol as endogenous ligands in the RPE and retina and mutations in human CRALBP that destroy retinoid binding functionality have been linked to autosomal recessive retinitis pigmentosa. CRALBP is also present in brain without endogenous retinoids, suggesting other ligands and physiological roles exist for the protein. Human recombinant cellular retinaldehyde-binding protein (rCRALBP) has been over expressed as non-fusion and fusion proteins in Escherichia coli from pET3a and pET19b vectors, respectively. The recombinant proteins typically constitute 15-20% of the soluble bacterial lysate protein and after purification, yield about 3-8 mg per liter of bacterial culture. Liquid chromatography electrospray mass spectrometry, amino acid analysis, and Edman degradation were used to demonstrate that rCRALBP exhibits the correct primary structure and mass. Circular dichroism, retinoid HPLC, UV-visible absorption spectroscopy, and solution state 19F-NMR were used to characterize the secondary structure and retinoid binding properties of rCRALBP. Human rCRALBP appears virtually identical to bovine retinal CRALBP in terms of secondary structure, thermal stability, and stereoselective retinoid-binding properties. Ligand-dependent conformational changes appear to influence a newly detected difference in the bathochromic shift exhibited by bovine and human CRALBP when complexed with 9-cis-retinal. These recombinant preparations provide valid models for human CRALBP structure-function studies. PMID:9541407

  1. Uniaxial cell stretching device for live-cell imaging of mechanosensitive cellular functions

    NASA Astrophysics Data System (ADS)

    Shao, Yue; Tan, Xinyu; Novitski, Roman; Muqaddam, Mishaal; List, Paul; Williamson, Laura; Fu, Jianping; Liu, Allen P.

    2013-11-01

    External mechanical stretch plays an important role in regulating cellular behaviors through intracellular mechanosensitive and mechanotransductive machineries such as the F-actin cytoskeleton (CSK) structures and focal adhesions (FAs) anchoring the F-actin CSK to the extracellular environment. Studying the mechanoresponsive behaviors of the F-actin CSK and FAs in response to cell stretch has great importance for further understanding mechanotransduction and mechanobiology. In this work, we developed a novel cell stretching device combining dynamic directional cell stretch with in situ subcellular live-cell imaging. Using a cam and follower mechanism and applying a standard mathematical model for cam design, we generated different dynamic stretch outputs. By examining stretch-mediated FA dynamics under step-function static stretch and the realignment of cell morphology and the F-actin CSK under cyclic stretch, we demonstrated successful applications of our cell stretching device for mechanobiology studies where external stretch plays an important role in regulating subcellular molecular dynamics and cellular phenotypes.

  2. Expression and functional analysis of mussel taurine transporter, as a key molecule in cellular osmoconforming.

    PubMed

    Hosoi, Masatomi; Takeuchi, Kazuharu; Sawada, Hideki; Toyohara, Haruhiko

    2005-11-01

    Most aquatic invertebrates adapt to environmental osmotic changes primarily by the cellular osmoconforming process, in which osmolytes accumulated in their cells play an essential role. Taurine is one of the most widely utilized osmolytes and the most abundant in many molluscs. Here, we report the structure, function and expression of the taurine transporter in the Mediterranean blue mussel (muTAUT), as a key molecule in the cellular osmoconforming process. Deduced amino acid sequence identity among muTAUT and vertebrate taurine transporters is lower (47-51%) than that among vertebrate taurine transporters (>78%). muTAUT has a lower affinity and specificity for taurine and a requirement for higher NaCl concentration than vertebrate taurine transporters. This seems to reflect the internal environment of the mussel; higher NaCl and taurine concentrations. In addition to the hyperosmotic induction that has been reported for cloned taurine transporters, the increase in muTAUT mRNA was unexpectedly observed under hypoosmolality, which was depressed by the addition of taurine to ambient seawater. In view of the decrease in taurine content in mussel tissue under conditions of hypoosmolality reported previously, our results lead to the conclusion that muTAUT does not respond directly to hypoosmolality, but to the consequent decrease in taurine content. By immunohistochemistry, intensive expression of muTAUT was observed in the gill and epithelium of the mantle, which were directly exposed to intensive osmotic changes of ambient seawater. PMID:16272243

  3. Pleiotropic Cellular Functions of PARP1 in Longevity and Aging: Genome Maintenance Meets Inflammation

    PubMed Central

    Mangerich, Aswin; Bürkle, Alexander

    2012-01-01

    Aging is a multifactorial process that depends on diverse molecular and cellular mechanisms, such as genome maintenance and inflammation. The nuclear enzyme poly(ADP-ribose) polymerase 1 (PARP1), which catalyzes the synthesis of the biopolymer poly(ADP-ribose), exhibits an essential role in both processes. On the one hand, PARP1 serves as a genomic caretaker as it participates in chromatin remodelling, DNA repair, telomere maintenance, resolution of replicative stress, and cell cycle control. On the other hand, PARP1 acts as a mediator of inflammation due to its function as a regulator of NF-κB and other transcription factors and its potential to induce cell death. Consequently, PARP1 represents an interesting player in several aging mechanisms and is discussed as a longevity assurance factor on the one hand and an aging-promoting factor on the other hand. Here, we review the molecular mechanisms underlying the various roles of PARP1 in longevity and aging with special emphasis on cellular studies and we briefly discuss the results in the context of in vivo studies in mice and humans. PMID:23050038

  4. Uniaxial cell stretching device for live-cell imaging of mechanosensitive cellular functions

    PubMed Central

    Shao, Yue; Tan, Xinyu; Novitski, Roman; Muqaddam, Mishaal; List, Paul; Williamson, Laura; Fu, Jianping; Liu, Allen P.

    2013-01-01

    External mechanical stretch plays an important role in regulating cellular behaviors through intracellular mechanosensitive and mechanotransductive machineries such as the F-actin cytoskeleton (CSK) structures and focal adhesions (FAs) anchoring the F-actin CSK to the extracellular environment. Studying the mechanoresponsive behaviors of the F-actin CSK and FAs in response to cell stretch has great importance for further understanding mechanotransduction and mechanobiology. In this work, we developed a novel cell stretching device combining dynamic directional cell stretch with in situ subcellular live-cell imaging. Using a cam and follower mechanism and applying a standard mathematical model for cam design, we generated different dynamic stretch outputs. By examining stretch-mediated FA dynamics under step-function static stretch and the realignment of cell morphology and the F-actin CSK under cyclic stretch, we demonstrated successful applications of our cell stretching device for mechanobiology studies where external stretch plays an important role in regulating subcellular molecular dynamics and cellular phenotypes. PMID:24289415

  5. Sprouty gain of function disrupts lens cellular processes and growth by restricting RTK signaling.

    PubMed

    Shin, Eun Hae; Zhao, Guannan; Wang, Qian; Lovicu, Frank J

    2015-10-15

    Sprouty proteins function as negative regulators of the receptor tyrosine kinase (RTK)-mediated Ras/Raf/MAPK pathway in many varied physiological and developmental processes, inhibiting growth factor-induced cellular proliferation, migration and differentiation. Like other negative regulators, Sprouty proteins are expressed in various organs during development, including the eye; ubiquitously expressed in the optic vesicle, lens pit, optic cup and lens vesicle. Given the synexpression of different antagonists (e.g, Sprouty, Sef, Spred) in the developing lens, to gain a better understanding of their specific role, in particular, their ability to regulate ocular growth factor signaling in lens cells, we characterized transgenic mice overexpressing Sprouty1 or Sprouty2 in the eye. Overexpression of Sprouty in the lens resulted in reduced lens and eye size during ocular morphogenesis, influenced by changes to the lens epithelium, aberrant fiber cell differentiation and compromised de novo maintenance of the lens capsule. Here we demonstrate an important inhibitory role for Sprouty in the regulation of lens cell proliferation and fiber differentiation in situ, potentially through its ability to modulate FGF- (and even EGF-) mediated MAPK/ERK1/2 signaling in lens cells. Whilst growth factor regulation of lens cell proliferation and fiber differentiation are required for orchestrating lens morphogenesis and growth, in turn, antagonists such as Sprouty are just as important for regulating the intracellular signaling pathways driving lens cellular processes. PMID:26375880

  6. Multiple functional nanoprobe for contrast-enhanced bimodal cellular imaging and targeted therapy.

    PubMed

    Meng, Hong-Min; Lu, Limin; Zhao, Xu-Hua; Chen, Zhuo; Zhao, Zilong; Yang, Chan; Zhang, Xiao-Bing; Tan, Weihong

    2015-04-21

    Many one-photon fluorescence-based theranostic nanosystems have been developed for simultaneous therapeutic intervention/monitoring for various types of cancers. However, for early diagnosis of cancer, two-photon fluorescence microscopy (TPFM) can realize deep-tissue imaging with higher spatial resolution. In this study, we first report a multiple functional nanoprobe for contrast-enhanced bimodal cellular imaging and targeted therapy. Components of the nanoprobe include (1) two-photon dye-doped mesoporous silica nanoparticles (TPD-MSNs); (2) MnO2 nanosheets that act as a (i) gatekeeper for TPD-MSNs, (ii) quencher for TP fluorescence, and (iii) contrast agent for MRI; (3) cancer cell-targeting aptamers. Guided by aptamers, TPD-MSNs are rapidly internalized into the target cells. Next, intracellular glutathione reduces MnO2 to Mn(2+) ions, resulting in contrast-enhanced TP fluorescence and magnetic resonance signal for cellular imaging. Meanwhile, preloaded doxorubicin and Chlorin e6 are released for chemotherapy and photodynamic therapy, respectively, with a synergistic effect and significantly enhanced therapeutic efficacy. PMID:25791340

  7. A Current View of Functional Biomaterials for Wound Care, Molecular and Cellular Therapies

    PubMed Central

    Piraino, Francesco; Selimović, Šeila

    2015-01-01

    The intricate process of wound healing involves activation of biological pathways that work in concert to regenerate a tissue microenvironment consisting of cells and external cellular matrix (ECM) with enzymes, cytokines, and growth factors. Distinct stages characterize the mammalian response to tissue injury: hemostasis, inflammation, new tissue formation, and tissue remodeling. Hemostasis and inflammation start right after the injury, while the formation of new tissue, along with migration and proliferation of cells within the wound site, occurs during the first week to ten days after the injury. In this review paper, we discuss approaches in tissue engineering and regenerative medicine to address each of these processes through the application of biomaterials, either as support to the native microenvironment or as delivery vehicles for functional hemostatic, antibacterial, or anti-inflammatory agents. Molecular therapies are also discussed with particular attention to drug delivery methods and gene therapies. Finally, cellular treatments are reviewed, and an outlook on the future of drug delivery and wound care biomaterials is provided. PMID:26509154

  8. Bisphenol A affects androgen receptor function via multiple mechanisms

    PubMed Central

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B. Alex; Jetten, Anton M.; Austin, Christopher, P.; Tice, Raymond R.

    2013-01-01

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. PMID:23562765

  9. Bisphenol A affects androgen receptor function via multiple mechanisms.

    PubMed

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B Alex; Jetten, Anton M; Austin, Christopher P; Tice, Raymond R

    2013-05-25

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. PMID:23562765

  10. Protein partners of the calcium channel β subunit highlight new cellular functions.

    PubMed

    Rima, Mohamad; Daghsni, Marwa; Fajloun, Ziad; M'rad, Ridha; Brusés, Juan L; Ronjat, Michel; De Waard, Michel

    2016-07-01

    Calcium plays a key role in cell signalling by its intervention in a wide range of physiological processes. Its entry into cells occurs mainly via voltage-gated calcium channels (VGCC), which are found not only in the plasma membrane of excitable cells but also in cells insensitive to electrical signals. VGCC are composed of different subunits, α1, β, α2δ and γ, among which the cytosolic β subunit (Cavβ) controls the trafficking of the channel to the plasma membrane, its regulation and its gating properties. For many years, these were the main functions associated with Cavβ. However, a growing number of proteins have been found to interact with Cavβ, emphasizing the multifunctional role of this versatile protein. Interestingly, some of the newly assigned functions of Cavβ are independent of its role in the regulation of VGCC, and thus further increase its functional roles. Based on the identity of Cavβ protein partners, this review emphasizes the diverse cellular functions of Cavβ and summarizes both past findings as well as recent progress in the understanding of VGCC. PMID:27354560

  11. Human promoter genomic composition demonstrates non-random groupings that reflect general cellular function

    PubMed Central

    McNutt, Markey C; Tongbai, Ron; Cui, Wenwu; Collins, Irene; Freebern, Wendy J; Montano, Idalia; Haggerty, Cynthia M; Chandramouli, GVR; Gardner, Kevin

    2005-01-01

    Background The purpose of this study is to determine whether or not there exists nonrandom grouping of cis-regulatory elements within gene promoters that can be perceived independent of gene expression data and whether or not there is any correlation between this grouping and the biological function of the gene. Results Using ProSpector, a web-based promoter search and annotation tool, we have applied an unbiased approach to analyze the transcription factor binding site frequencies of 1400 base pair genomic segments positioned at 1200 base pairs upstream and 200 base pairs downstream of the transcriptional start site of 7298 commonly studied human genes. Partitional clustering of the transcription factor binding site composition within these promoter segments reveals a small number of gene groups that are selectively enriched for gene ontology terms consistent with distinct aspects of cellular function. Significance ranking of the class-determining transcription factor binding sites within these clusters show substantial overlap between the gene ontology terms of the transcriptions factors associated with the binding sites and the gene ontology terms of the regulated genes within each group. Conclusion Thus, gene sorting by promoter composition alone produces partitions in which the "regulated" and the "regulators" cosegregate into similar functional classes. These findings demonstrate that the transcription factor binding site composition is non-randomly distributed between gene promoters in a manner that reflects and partially defines general gene class function. PMID:16232321

  12. Can lifestyle modification affect men’s erectile function?

    PubMed Central

    Hehemann, Marah C.

    2016-01-01

    Erectile dysfunction (ED) is a common condition affecting millions of men worldwide. The pathophysiology and epidemiologic links between ED and risk factors for cardiovascular disease (CVD) are well-established. Lifestyle modifications such as smoking cessation, weight reduction, dietary modification, physical activity, and psychological stress reduction have been increasingly recognized as foundational to the prevention and treatment of ED. The aim of this review is to outline behavioral choices which may increase ones risk of developing ED, to present relevant studies addressing lifestyle factors correlated with ED, and to highlight proposed mechanisms for intervention aimed at improving erectile function in men with ED. These recommendations can provide a framework for counseling patients with ED about lifestyle modification. PMID:27141445

  13. The VCP/p97 system at a glance: connecting cellular function to disease pathogenesis

    PubMed Central

    Meyer, Hemmo; Weihl, Conrad C.

    2014-01-01

    ABSTRACT The ATPase valosin-containing protein (VCP)/p97 has emerged as a central and important element of the ubiquitin system. Together with a network of cofactors, it regulates an ever-expanding range of processes that stretch into almost every aspect of cellular physiology. Its main role in proteostasis and key functions in signaling pathways are of relevance to degenerative diseases and genomic stability. In this Cell Science at a Glance and the accompanying poster, we give a brief overview of this complex system. In addition, we discuss the pathogenic basis for VCP/p97-associated diseases and then highlight in more detail new exciting links to the translational stress response and RNA biology that further underscore the significance of the VCP/p97 system. PMID:25146396

  14. Real-time cellular analysis for quantitative detection of functional Clostridium difficile toxin in stool.

    PubMed

    Huang, Bin; Li, Haijing; Jin, Dazhi; Stratton, Charles W; Tang, Yi-Wei

    2014-04-01

    Rapid and accurate diagnosis and monitoring of Clostridium difficile infection (CDI) is critical for patient care and infection control. We will briefly review current laboratory techniques for the diagnosis of CDI and identify aspects needing improvement. We will also introduce a real-time cellular analysis (RTCA) assay developed for the diagnosis and monitoring of CDI using electronic impedance to assess the cell status. The RTCA assay uses impedance measurement to detect minute physiological changes in cells cultured on gold microelectrodes embedded in glass substrates in the bottom of microtiter wells. This assay has been adapted for quantitative detection of C. difficile functional toxin directly from stool specimens. Compared to conventional techniques and molecular assays, the RTCA assay provides a valuable tool for the diagnosis of CDI as well as for the assessment of clinical severity and for monitoring therapeutic efficacies. PMID:24649817

  15. Nathan Shock Memorial Lecture 1992. Aging and immune function: cellular and biochemical analyses.

    PubMed

    Miller, R A

    1994-01-01

    Recent progress on the cellular and molecular basis for T cell dysfunction in aged mice is reviewed, with emphasis on defects in calcium signal generation and protein kinase function. The accumulation in older mice of memory T cells at the expense of naive T cells seems to account for most of the decline in the proportion of cells that can secrete or respond to interleukin 2. Memory T cells in mice of any age have an intrinsic resistance to increases in cytoplasmic free calcium ion concentration, which in turn interferes with their responses to polyclonal activators. T cells from old mice also exhibit declines both in serine/threonine and in tyrosine-specific protein kinase signals after activation by either receptor-dependent or receptor-independent agonists. PMID:8187838

  16. Scorpion venom components that affect ion-channels function

    PubMed Central

    Quintero-Hernández, V.; Jiménez-Vargas, J.M.; Gurrola, G.B.; Valdivia, H.H.F.; Possani, L.D.

    2014-01-01

    SUMMARY The number and types of venom components that affect ion-channel function are reviewed. These are the most important venom components responsible for human intoxication, deserving medical attention, often requiring the use of specific anti-venoms. Special emphasis is given to peptides that recognize Na+-, K+- and Ca++-channels of excitable cells. Knowledge generated by direct isolation of peptides from venom and components deduced from cloned genes, whose amino acid sequences are deposited into databanks are now adays in the order of 1.5 thousands, out of an estimate biodiversity closed to 300,000. Here the diversity of components is briefly reviewed with mention to specific references. Structural characteristic are discussed with examples taken from published work. The principal mechanisms of action of the three different types of peptides are also reviewed. Na+-channel specific venom components usually are modifier of the open and closing kinetic mechanisms of the ion-channels, whereas peptides affecting K+-channels are normally pore blocking agents. The Ryanodine Ca++-channel specific peptides are known for causing sub-conducting stages of the channels conductance and some were shown to be able to internalize penetrating inside the muscle cells. PMID:23891887

  17. Cellular Growth and Mitochondrial Ultrastructure of Leishmania (Viannia) braziliensis Promastigotes Are Affected by the Iron Chelator 2,2-Dipyridyl

    PubMed Central

    Mesquita-Rodrigues, Camila; Menna-Barreto, Rubem F. S.; Sabóia-Vahia, Leonardo; Da-Silva, Silvia A. G.; de Souza, Elen M.; Waghabi, Mariana C.; Cuervo, Patrícia; De Jesus, José B.

    2013-01-01

    Background Iron is an essential element for the survival of microorganisms in vitro and in vivo, acting as a cofactor of several enzymes and playing a critical role in host-parasite relationships. Leishmania (Viannia) braziliensis is a parasite that is widespread in the new world and considered the major etiological agent of American tegumentary leishmaniasis. Although iron depletion leads to promastigote and amastigote growth inhibition, little is known about the role of iron in the biology of Leishmania. Furthermore, there are no reports regarding the importance of iron for L. (V.) braziliensis. Methodology/Principal Findings In this study, the effect of iron on the growth, ultrastructure and protein expression of L. (V.) braziliensis was analyzed by the use of the chelator 2,2-dipyridyl. Treatment with 2,2-dipyridyl affected parasites' growth in a dose- and time-dependent manner. Multiplication of the parasites was recovered after reinoculation in fresh culture medium. Ultrastructural analysis of treated promastigotes revealed marked mitochondrial swelling with loss of cristae and matrix and the presence of concentric membranar structures inside the organelle. Iron depletion also induced Golgi disruption and intense cytoplasmic vacuolization. Fluorescence-activated cell sorting analysis of tetramethylrhodamine ester-stained parasites showed that 2,2-dipyridyl collapsed the mitochondrial membrane potential. The incubation of parasites with propidium iodide demonstrated that disruption of mitochondrial membrane potential was not associated with plasma membrane permeabilization. TUNEL assays indicated no DNA fragmentation in chelator-treated promastigotes. In addition, two-dimensional electrophoresis showed that treatment with the iron chelator induced up- or down-regulation of proteins involved in metabolism of nucleic acids and coordination of post-translational modifications, without altering their mRNA levels. Conclusions Iron chelation leads to a

  18. Flow-cytometric study of vital cellular functions in Escherichia coli during solar disinfection (SODIS).

    PubMed

    Berney, Michael; Weilenmann, Hans-Ulrich; Egli, Thomas

    2006-06-01

    The effectiveness of solar disinfection (SODIS), a low-cost household water treatment method for developing countries, was investigated with flow cytometry and viability stains for the enteric bacterium Escherichia coli. A better understanding of the process of injury or death of E. coli during SODIS could be gained by investigating six different cellular functions, namely: efflux pump activity (Syto 9 plus ethidium bromide), membrane potential [bis-(1,3-dibutylbarbituric acid)trimethine oxonol; DiBAC4(3)], membrane integrity (LIVE/DEAD BacLight), glucose uptake activity (2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose; 2-NBDG), total ATP concentration (BacTiter-Glo) and culturability (pour-plate method). These variables were measured in E. coli K-12 MG1655 cells that were exposed to either sunlight or artificial UVA light. The inactivation pattern of cellular functions was very similar for both light sources. A UVA light dose (fluence) of <500 kJ m(-2) was enough to lower the proton motive force, such that efflux pump activity and ATP synthesis decreased significantly. The loss of membrane potential, glucose uptake activity and culturability of >80 % of the cells was observed at a fluence of approximately 1500 kJ m(-2), and the cytoplasmic membrane of bacterial cells became permeable at a fluence of >2500 kJ m(-2). Culturable counts of stressed bacteria after anaerobic incubation on sodium pyruvate-supplemented tryptic soy agar closely correlated with the loss of membrane potential. The results strongly suggest that cells exposed to >1500 kJ m(-2) solar UVA (corresponding to 530 W m(-2) global sunlight intensity for 6 h) were no longer able to repair the damage and recover. Our study confirms the lethal effect of SODIS with cultivation-independent methods and gives a detailed picture of the 'agony' of E. coli when it is stressed with sunlight. PMID:16735735

  19. Cellular prostatic acid phosphatase, a PTEN-functional homologue in prostate epithelia, functions as a prostate-specific tumor suppressor

    PubMed Central

    Muniyan, Sakthivel; Ingersoll, Matthew A.; Batra, Surinder K.; Lin, Ming-Fong

    2014-01-01

    The inactivation of tumor suppressor genes (TSGs) plays a vital role in the progression of human cancers. Nevertheless, those ubiquitous TSGs have been shown with limited roles in various stages of diverse carcinogenesis. Investigation on identifying unique TSG, especially for early stage of carcinogenesis, is imperative. As such, the search for organ-specific TSGs has emerged as a major strategy in cancer research. Prostate cancer (PCa) has the highest incidence in solid tumors in US males. Cellular prostatic acid phosphatase (cPAcP) is a prostate-specific differentiation antigen. Despite intensive studies over the past several decades on PAcP as a PCa biomarker, the role of cPAcP as a PCa-specific tumor suppressor has only recently been emerged and validated. The mechanism underlying the pivotal role of cPAcP as a prostate-specific TSG is, in part, due to its function as a protein tyrosine phosphatase (PTP) as well as a phosphoinositide phosphatase (PIP), an apparent functional homologue to Phosphatase and tensin homolog (PTEN) in PCa cells. This review is focused on discussing the function of this authentic prostate-specific tumor suppressor and the mechanism behind the loss of cPAcP expression leading to prostate carcinogenesis. We review other phosphatases’ roles as TSGs which regulate oncogenic PI3K signaling in PCa and discuss the functional similarity between cPAcP and PTEN in prostate carcinogenesis. PMID:24747769

  20. Epoxy-functionalized mesostructured cellular foams as effective support for covalent immobilization of penicillin G acylase

    NASA Astrophysics Data System (ADS)

    Xue, Ping; Xu, Fang; Xu, Lidong

    2008-12-01

    The epoxy-functionalized mesoporous cellular foams (G-MCFs) with high specific surface area (˜400 m 2/g) and large-size mesopores (˜17 nm) were obtained by condensation of 3-glycidoxypropyltriethoxysilane (GPTS) and the surface silanol groups of mesoporous cellular foams (MCFs) and used as the support for immobilization of penicillin G acylase (PGA). The structural properties of G-MCF were characterized by FT-IR, N 2 adsorption, TG-DTA and 29Si MAS NMR. The studies indicated that the glycidoxypropyl groups were chemically bonded to the silicon atoms on the surface of MCF. The epoxy-functionalized mesoporous cellular foams can provide the microenvironments suitable for the immobilization of PGA, and the enzyme molecules could be immobilized covalently onto the G-MCF under mild conditions by reaction between the amino groups of the enzyme molecules and the epoxy groups on the surface of G-MCF. The PGA immobilized on G-MCF (PGA/G-MCF) exhibited the apparent activity of 1782 IU/g and 46.6% of activity recovery for hydrolyzing penicillin G potassium to produce 6-aminopenicillanic acid at 37 °C which were higher than that of PGA on pure silica MCF (1521 IU/g and 39.8%, respectively). The kinetic study also indicated that PGA immobilized on G-MCF has a Km of 2.1 × 10 -2 mol/L lower than that of PGA immobilized on the pure silica MCF (5.0 × 10 -2 mol/L). These may be attributed to the enhanced surface affinity between G-MCF support and the substrate molecules. Due to the covalent immobilization of PGA molecules on the surface of G-MCF, the immobilized PGA with considerable operational stability was achieved. The activity of PGA/G-MCF is still about 91.4% of its initial activity at the 10th cycle reuse while that of PGA/MCF only remains 41.5% of its initial activity at the same reuse numbers. In addition, the investigation results show the thermal stability and durability on acid or basic medium of PGA immobilized on G-MCF were improved remarkably.

  1. The extra nuclear control of mitosis & cell function. A theory of cellular organisation.

    PubMed

    Holt, J A

    1980-02-01

    There is evidence to suggest that the extra nuclear cell constituents are the part of the cell which contains all the biochemical mechanisms responsible for implementing all cell functions. These functions include control of cell division, growth, response to injury, replacement of effete cells, maintenance of anatomical and spatial cellular relations and specific cellular function and structure. The energy to perform these functions is derived from the aerobic metabolism of glucose. The energy required for nuclear division appears to be wholly or partly derived from the anaerobic metabolism of glucose. Ethyl alcohol interferes with the aerobic metabolic pathways and thus disrupts or diminishes all aerobically activated cell functions. The speed of all activities motivated by aerobic glycolysis can be increased by appropriate electrical stimulations delivered from any of a range of electromagnetic radiation frequencies tested. In addition to the stimulant effect on aerobic metabolic processes, 434 MHz can stimulate the anaerobic glucose metabolism of cancer with consequent stimulation of cancer growth rate. 434 MHz appears to deliver energy to the anaerobic cancer metabolism by causing a resonance phenomenon amongst one or more of the substrates which comprise the first few stages of glycolysis. This phenomenon permits the selective delivery of electromagnetic radiation energy to cancer cells which, if sufficiently intense, causes injury to cancer cells without harm to the normal cells except when the latter are in the phase of anaerobic metabolism which occurs at some stage of the mitotic cycle. Streptokinase, ethanol and glucose analogues increase the lethal effects on cancers undergoing therapy with 434 MHz radiation and observations of such responses suggest a theoretical basis to explain the rare spontaneous remissions of human cancer. Cancer appears to protect its glucose supplies by elevating the blood glucose levels above normal and by some mechanism which

  2. Integrating Negative Affect Measures in a Measurement Model: Assessing the Function of Negative Affect as Interference to Self-Regulation

    ERIC Educational Resources Information Center

    Magno, Carlo

    2010-01-01

    The present study investigated the composition of negative affect and its function as inhibitory to thought processes such as self-regulation. Negative affect in the present study were composed of anxiety, worry, thought suppression, and fear of negative evaluation. These four factors were selected based on the criteria of negative affect by…

  3. To what extent does urbanisation affect fragmented grassland functioning?

    PubMed

    van der Walt, L; Cilliers, S S; Kellner, K; Du Toit, M J; Tongway, D

    2015-03-15

    Urbanisation creates altered environments characterised by increased human habitation, impermeable surfaces, artificial structures, landscape fragmentation, habitat loss, resulting in different resource loss pathways. The vulnerable Rand Highveld Grassland vegetation unit in the Tlokwe Municipal area, South Africa, has been extensively affected and transformed by urbanisation, agriculture, and mining. Grassland fragments in urban areas are often considered to be less species rich and less functional than in the more untransformed or "natural" exurban environments, and are therefore seldom a priority for conservation. Furthermore, urban grassland fragments are often being more intensely managed than exurban areas, such as consistent mowing in open urban areas. Four urbanisation measures acting as indicators for patterns and processes associated with urban areas were calculated for matrix areas surrounding each selected grassland fragment to quantify the position of each grassland remnant along an urbanisation gradient. The grassland fragments were objectively classified into two classes of urbanisation, namely "exurban" and "urban" based on the urbanisation measure values. Grazing was recorded in some exurban grasslands and mowing in some urban grassland fragments. Unmanaged grassland fragments were present in both urban and exurban areas. Fine-scale biophysical landscape function was determined by executing the Landscape Function Analysis (LFA) method. LFA assesses fine-scale landscape patchiness (entailing resource conserving potential and erosion resistance) and 11 soil surface indicators to produce three main LFA parameters (stability, infiltration, and nutrient cycling), which indicates how well a system is functioning in terms of fine-scale biophysical soil processes and characteristics. The aim of this study was to determine the effects of urbanisation and associated management practices on fine-scale biophysical landscape function of urban and exurban

  4. NFAT5 in cellular adaptation to hypertonic stress - regulations and functional significance.

    PubMed

    Cheung, Chris Yk; Ko, Ben Cb

    2013-01-01

    The Nuclear Factor of Activated T Cells-5 (NFAT5), also known as OREBP or TonEBP, is a member of the nuclear factors of the activated T cells family of transcription factors. It is also the only known tonicity-regulated transcription factor in mammals. NFAT5 was initially known for its role in the hypertonic kidney inner medulla for orchestrating a genetic program to restore the cellular homeostasis. Emerging evidence, however, suggests that NFAT5 might play a more diverse functional role, including a pivotal role in blood pressure regulation and the development of autoimmune diseases. Despite the growing significance of NFAT5 in physiology and diseases, our understanding of how its activity is regulated remains very limited. Furthermore, how changes in tonicities are converted into functional outputs via NFAT5 remains elusive. Therefore, this review aims to summarize our current knowledge on the functional roles of NFAT5 in osmotic stress adaptation and the signaling pathways that regulate its activity. PMID:23618372

  5. Numerically evaluated functional equivalence between chaotic dynamics in neural networks and cellular automata under totalistic rules.

    PubMed

    Takada, Ryu; Munetaka, Daigo; Kobayashi, Shoji; Suemitsu, Yoshikazu; Nara, Shigetoshi

    2007-09-01

    Chaotic dynamics in a recurrent neural network model and in two-dimensional cellular automata, where both have finite but large degrees of freedom, are investigated from the viewpoint of harnessing chaos and are applied to motion control to indicate that both have potential capabilities for complex function control by simple rule(s). An important point is that chaotic dynamics generated in these two systems give us autonomous complex pattern dynamics itinerating through intermediate state points between embedded patterns (attractors) in high-dimensional state space. An application of these chaotic dynamics to complex controlling is proposed based on an idea that with the use of simple adaptive switching between a weakly chaotic regime and a strongly chaotic regime, complex problems can be solved. As an actual example, a two-dimensional maze, where it should be noted that the spatial structure of the maze is one of typical ill-posed problems, is solved with the use of chaos in both systems. Our computer simulations show that the success rate over 300 trials is much better, at least, than that of a random number generator. Our functional simulations indicate that both systems are almost equivalent from the viewpoint of functional aspects based on our idea, harnessing of chaos. PMID:19003512

  6. The functional micro-organization of grid cells revealed by cellular-resolution imaging

    PubMed Central

    Heys, James G.; Rangarajan, Krsna V.; Dombeck, Daniel A.

    2015-01-01

    Summary Establishing how grid cells are anatomically arranged, on a microscopic scale, in relation to their firing patterns in the environment would facilitate a greater micro-circuit level understanding of the brain’s representation of space. However, all previous grid cell recordings used electrode techniques that provide limited descriptions of fine-scale organization. We therefore developed a technique for cellular-resolution functional imaging of medial entorhinal cortex (MEC) neurons in mice navigating a virtual linear track, enabling a new experimental approach to study MEC. Using these methods, we show that grid cells are physically clustered in MEC compared to non-grid cells. Additionally, we demonstrate that grid cells are functionally micro-organized: The similarity between the environment firing locations of grid cell pairs varies as a function of the distance between them according to a “Mexican Hat” shaped profile. This suggests that, on average, nearby grid cells have more similar spatial firing phases than those further apart. PMID:25467986

  7. Multi-functional MIMO communication in multi-hop cellular systems

    NASA Astrophysics Data System (ADS)

    Roger, Sandra; Calabuig, Daniel; Monserrat, Jose F.; Cardona, Narcis

    2014-12-01

    In the context of multi-hop cellular communications, user equipment devices (UEs) with relaying capabilities provide a virtual infrastructure that can enhance the cell spectral efficiency. UE relays, which are generally transparent to the destination user and lack channel state information, mainly operate in an open-loop mode. Most open-loop transmission techniques for relaying are based on orthogonal space-time block coding (OSTBC), which offers a good trade-off between performance and complexity. In this paper, we consider the concept of multi-functional multiple-input multiple-output (MIMO) transmission, which combines OSTBC with beamforming techniques. This concept is applied to networks with multiple relays, which can offer a high number of antennas to implement multi-functional MIMO techniques. The proposed schemes are shown to reduce the bit error rate of the destination user with respect to a direct transmission from the base station (BS). Furthermore, the multi-functional setup exhibits better performance than conventional OSTBC at high transmission rates.

  8. Does Ramadan Fasting Adversely Affect Cognitive Function in Young Females?

    PubMed Central

    Ghayour Najafabadi, Mahboubeh; Rahbar Nikoukar, Laya; Memari, Amir; Ekhtiari, Hamed; Beygi, Sara

    2015-01-01

    We examined the effects of Ramadan fasting on cognitive function in 17 female athletes. Data were obtained from participants of two fasting (n = 9) and nonfasting (n = 8) groups at three periods of the study (before Ramadan, at the third week in Ramadan, and after Ramadan). Digit span test (DST) and Stroop color test were employed to assess short-term memory and inhibition/cognitive flexibility at each time point. There were no significant changes for DST and Stroop task 1 in both groups, whereas Stroop task 2 and task 3 showed significant improvements in Ramadan condition (p < 0.05). Interference indices did not change significantly across the study except in post-Ramadan period of fasting group (p < 0.05). Group × week interaction was significant only for error numbers (p < 0.05). Athletes in nonfasting showed a significant decrease in number of errors in Ramadan compared to baseline (p < 0.05). The results suggest that Ramadan fasting may not adversely affect cognitive function in female athletes. PMID:26697263

  9. Grape polyphenols do not affect vascular function in healthy men.

    PubMed

    van Mierlo, Linda A J; Zock, Peter L; van der Knaap, Henk C M; Draijer, Richard

    2010-10-01

    Data suggest that polyphenol-rich products may improve endothelial function and other cardiovascular health risk factors. Grape and wine contain high amounts of polyphenols, but effects of these polyphenols have hardly been investigated in isolation in randomized controlled studies. Our objective in this study was to test the chronic effect of polyphenol-rich solids derived from either a wine grape mix or grape seed on flow-mediated dilation (FMD). Blood pressure and other vascular function measures, platelet function, and blood lipids were secondary outcomes. Thirty-five healthy males were randomized in a double-blind, placebo-controlled crossover study consisting of three 2-wk intervention periods separated by 1-wk washout periods. The test products, containing 800 mg of polyphenols, were consumed as capsules. At the end of each intervention period, effects were measured after consumption of a low-fat breakfast (~751 kJ, 25% fat) and a high-fat lunch (~3136 kJ, 78% fat). After the low-fat breakfast, the treatments did not significantly affect FMD. The absolute difference after the wine grape solid treatment was -0.4% (95% CI = -1.8 to 0.9; P = 0.77) and after grape seed solids, 0.2% (95% CI = -1.2 to 1.5; P = 0.94) compared with after the placebo treatment. FMD effects after the high-fat lunch and effects on secondary outcomes also showed no consistent differences between both of the grape solids and placebo treatment. In conclusion, consumption of grape polyphenols has no major impact on FMD in healthy men. Future studies should address whether grape polyphenols can improve FMD and other cardiovascular health risk factors in populations with increased cardiovascular risk. PMID:20702747

  10. Does Bowel Preparation for Colonoscopy Affect Cognitive Function?

    PubMed Central

    Wadsworth, P.; Blackburne, H.; Dixon, L.; Dobbs, B.; Eglinton, T.; Ing, A.; Mulder, R.; Porter, R.J.; Wakeman, C.; Frizelle, F.A.

    2015-01-01

    Abstract Colonoscopy is a common procedure used in the diagnosis and treatment of a range of bowel disorders. Prior preparation involving potent laxatives is a necessary stage to ensure adequate visualization of the bowel wall. It is known that the sedatives given to most patients during the colonoscopy cause a temporary impairment in cognitive function; however, the potential for bowel preparation to affect cognitive function has not previously been investigated. To assess the effect of bowel preparation for colonoscopy on cognitive function. This was a prospective, nonrandomized controlled study of cognitive function in patients who had bowel preparation for colonoscopy compared with those having gastroscopy and therefore no bowel preparation. Cognitive function was assessed using the Modified Mini Mental State Examination (MMMSE) and selected tests from the Cambridge Neuropsychological Test Automated Battery. Individual test scores and changes between initial and subsequent tests were compared between the groups. Age, gender, and weight were also compared. Forty-three colonoscopy and 25 gastroscopy patients were recruited. The 2 groups were similar for age and gender; however, patients having gastroscopy were heavier. MMMSE scores for colonoscopy and gastroscopy groups, respectively, were 28.6 and 29.5 (P = 0.24) at baseline, 28.7 and 29.8 (P = 0.32) at test 2, 28.1 and 28.5 (P = 0.76) at test 3. Motor screening scores for colonoscopy and gastroscopy groups, respectively, were 349.3 and 354.1 (P = 0.97) at baseline, 307.5 and 199.7 (P = 0.06) at test 2, 212.0 and 183.2 (P = 0.33) at test 3. Spatial working memory scores for colonoscopy and gastroscopy groups, respectively, were 14.4 and 6.7 (P = 0.29) at baseline, 9.7 and 4.3 (P = 0.27) at test 2, 10 and 4.5 (P = 0.33) at test 3. Digit Symbol Substitution Test scores for colonoscopy and gastroscopy groups, respectively, were 36.3 and 37.8 (P = 0.84) at baseline, 36.4 and

  11. Does Bowel Preparation for Colonoscopy Affect Cognitive Function?

    PubMed

    Wadsworth, P; Blackburne, H; Dixon, L; Dobbs, B; Eglinton, T; Ing, A; Mulder, R; Porter, R J; Wakeman, C; Frizelle, F A

    2015-11-01

    Colonoscopy is a common procedure used in the diagnosis and treatment of a range of bowel disorders. Prior preparation involving potent laxatives is a necessary stage to ensure adequate visualization of the bowel wall. It is known that the sedatives given to most patients during the colonoscopy cause a temporary impairment in cognitive function; however, the potential for bowel preparation to affect cognitive function has not previously been investigated. To assess the effect of bowel preparation for colonoscopy on cognitive function. This was a prospective, nonrandomized controlled study of cognitive function in patients who had bowel preparation for colonoscopy compared with those having gastroscopy and therefore no bowel preparation. Cognitive function was assessed using the Modified Mini Mental State Examination (MMMSE) and selected tests from the Cambridge Neuropsychological Test Automated Battery. Individual test scores and changes between initial and subsequent tests were compared between the groups. Age, gender, and weight were also compared. Forty-three colonoscopy and 25 gastroscopy patients were recruited. The 2 groups were similar for age and gender; however, patients having gastroscopy were heavier. MMMSE scores for colonoscopy and gastroscopy groups, respectively, were 28.6 and 29.5 (P = 0.24) at baseline, 28.7 and 29.8 (P = 0.32) at test 2, 28.1 and 28.5 (P = 0.76) at test 3. Motor screening scores for colonoscopy and gastroscopy groups, respectively, were 349.3 and 354.1 (P = 0.97) at baseline, 307.5 and 199.7 (P = 0.06) at test 2, 212.0 and 183.2 (P = 0.33) at test 3. Spatial working memory scores for colonoscopy and gastroscopy groups, respectively, were 14.4 and 6.7 (P = 0.29) at baseline, 9.7 and 4.3 (P = 0.27) at test 2, 10 and 4.5 (P = 0.33) at test 3. Digit Symbol Substitution Test scores for colonoscopy and gastroscopy groups, respectively, were 36.3 and 37.8 (P = 0.84) at baseline, 36.4 and 40.0 (P

  12. Symptoms of Problematic Cellular Phone Use, Functional Impairment and Its Association with Depression among Adolescents in Southern Taiwan

    ERIC Educational Resources Information Center

    Yen, Cheng-Fang; Tang, Tze-Chun; Yen, Ju-Yu; Lin, Huang-Chi; Huang, Chi-Fen; Liu, Shu-Chun; Ko, Chih-Hung

    2009-01-01

    The aims of this study were: (1) to examine the prevalence of symptoms of problematic cellular phone use (CPU); (2) to examine the associations between the symptoms of problematic CPU, functional impairment caused by CPU and the characteristics of CPU; (3) to establish the optimal cut-off point of the number of symptoms for functional impairment…

  13. 7SK small nuclear RNA directly affects HMGA1 function in transcription regulation

    PubMed Central

    Eilebrecht, Sebastian; Brysbaert, Guillaume; Wegert, Thomas; Urlaub, Henning; Benecke, Bernd-Joachim; Benecke, Arndt

    2011-01-01

    Non-coding (nc) RNAs are increasingly recognized to play important regulatory roles in eukaryotic gene expression. The highly abundant and essential 7SK ncRNA has been shown to negatively regulate RNA Polymerase II transcription by inactivating the positive transcription elongation factor b (P-TEFb) in cellular and Tat-dependent HIV transcription. Here, we identify a more general, P-TEFb-independent role of 7SK RNA in directly affecting the function of the architectural transcription factor and chromatin regulator HMGA1. An important regulatory role of 7SK RNA in HMGA1-dependent cell differentiation and proliferation regulation is uncovered with the identification of over 1500 7SK-responsive HMGA1 target genes. Elevated HMGA1 expression is observed in nearly every type of cancer making the use of a 7SK substructure in the inhibition of HMGA1 activity, as pioneered here, potentially useful in therapy. The 7SK-HMGA1 interaction not only adds an essential facet to the comprehension of transcriptional plasticity at the coupling of initiation and elongation, but also might provide a molecular link between HIV reprogramming of cellular gene expression-associated oncogenesis. PMID:21087998

  14. The function of EHD2 in endocytosis and defense signaling is affected by SUMO.

    PubMed

    Bar, Maya; Schuster, Silvia; Leibman, Meirav; Ezer, Ran; Avni, Adi

    2014-03-01

    Post-translational modification of target proteins by the small ubiquitin-like modifier protein (SUMO) regulates many cellular processes. SUMOylation has been shown to regulate cellular localization and function of a variety of proteins, in some cases affecting nuclear import or export. We have previously characterized two EHDs (EH domain containing proteins) in Arabidospis and showed their involvement in plant endocytosis. AtEHD2 has an inhibitory effect on endocytosis of transferrin, FM-4-64, and the leucine rich repeat receptor like protein LeEix2, an effect that requires and intact coiled-coil domain. Inhibition of endocytosis of LeEix2 by EHD2 is effective in inhibiting defense responses mediated by the LeEix2 receptor in response to its ligand EIX. In the present work we demonstrate that SUMOylation of EHD2 appears to be required for EHD2-induced inhibition of LeEix2 endocytosis. Indeed, we found that a mutant form of EHD2, possessing a defective SUMOylation site, has an increased nuclear abundance, can no longer be SUMOylated and is no longer effective in inhibiting LeEix2 endocytosis or defense signaling in response to EIX. PMID:24154852

  15. Cellular Trafficking of Phospholamban and Formation of Functional Sarcoplasmic Reticulum During Myocyte DIfferentiation

    SciTech Connect

    Stenoien, David L.; Knyushko, Tatyana V.; Londono, Monica P.; Opresko, Lee; Mayer, M. Uljana; Brady, Scott T.; Squier, Thomas C.; Bigelow, Diana J.

    2007-06-01

    The sarco/endoplasmic reticulum Ca-ATPase (SERCA) family members are transmembrane proteins that play an essential role in regulating intracellular calcium levels. Phospholamban (PLB), a 52 amino acid phosphoprotein, regulates SERCA activity in adult heart and skeletal muscle. Using the C2C12 myocyte cell line, we find endogenous PLB constitutively expressed in both myoblasts and myotubes, whereas SERCA expression coincides with activation of the differentiation program. PLB has a punctuate distribution in myoblasts changing to a reticular distribution in myotubes where it colocalizes with SERCAs. To examine the distribution and dynamics of PLB and SERCA, we expressed fluorescent fusion proteins (GFP, CFP, and YFP) of PLB and SERCA in myoblasts. Coexpressed PLB and SERCA localize to distinct cellular compartments in myoblasts but begin to colocalize as cells differentiate. Fluorescence Recovery After Photobleaching (FRAP) studies show different recovery patterns for each protein in myoblasts confirming their localization to distinct compartments. To extend these studies, we created stable cell lines expressing O6-alkylguanine-DNA alkyltransferase (AGT) fusions with PLB or SERCA to track their localization as myocytes differentiate. These experiments demonstrate that PLB localizes to punctate vesicles in myoblasts and adopts a reticular distribution that coincides with SERCA distribution after differentiation. Colocalization experiments indicate that a subset of PLB in myoblasts colocalizes with endosomes, Golgi, and the plasma membrane however PLB also localizes to other, as yet unidentified vesicles. Our results indicate that differentiation plays a critical role in regulating PLB distribution to ensure its colocalization within the same cellular compartment as SERCA in differentiated cells. The presence and altered distribution of PLB in undifferentiated myoblasts raises the possibility that this protein has additional functions distinct from SERCA regulation.

  16. Cellular cholesterol controls TRPC3 function: evidence from a novel dominant-negative knockdown strategy

    PubMed Central

    Graziani, Annarita; Rosker, Christian; Kohlwein, Sepp D.; Zhu, Michael X.; Romanin, Christoph; Sattler, Wolfgang; Groschner, Klaus; Poteser, Michael

    2006-01-01

    TRPC3 (canonical transient receptor potential protein 3) has been suggested to be a component of cation channel complexes that are targeted to cholesterol-rich lipid membrane microdomains. In the present study, we investigated the potential role of membrane cholesterol as a regulator of cellular TRPC3 conductances. Functional experiments demonstrated that cholesterol loading activates a non-selective cation conductance and a Ca2+ entry pathway in TRPC3-overexpressing cells but not in wild-type HEK-293 (human embryonic kidney 293) cells. The cholesterol-induced membrane conductance exhibited a current-to-voltage relationship similar to that observed upon PLC (phospholipase C)-dependent activation of TRPC3 channels. Nonetheless, the cholesterol-activated conductance lacked negative modulation by extracellular Ca2+, a typical feature of agonist-activated TRPC3 currents. Involvement of TRPC3 in the cholesterol-dependent membrane conductance was further corroborated by a novel dominant-negative strategy for selective blockade of TRPC3 channel activity. Expression of a TRPC3 mutant, which contained a haemagglutinin epitope tag in the second extracellular loop, conferred antibody sensitivity to both the classical PLC-activated as well as the cholesterol-activated conductance in TRPC3-expressing cells. Moreover, cholesterol loading as well as PLC stimulation was found to increase surface expression of TRPC3. Promotion of TRPC3 membrane expression by cholesterol was persistent over 30 min, while PLC-mediated enhancement of plasma membrane expression of TRPC3 was transient in nature. We suggest the cholesterol content of the plasma membrane as a determinant of cellular TRPC3 activity and provide evidence for cholesterol dependence of TRPC3 surface expression. PMID:16448384

  17. Cellular functions of the ADF/cofilin family at a glance.

    PubMed

    Kanellos, Georgios; Frame, Margaret C

    2016-09-01

    The actin depolymerizing factor (ADF)/cofilin family comprises small actin-binding proteins with crucial roles in development, tissue homeostasis and disease. They are best known for their roles in regulating actin dynamics by promoting actin treadmilling and thereby driving membrane protrusion and cell motility. However, recent discoveries have increased our understanding of the functions of these proteins beyond their well-characterized roles. This Cell Science at a Glance article and the accompanying poster serve as an introduction to the diverse roles of the ADF/cofilin family in cells. The first part of the article summarizes their actions in actin treadmilling and the main mechanisms for their intracellular regulation; the second part aims to provide an outline of the emerging cellular roles attributed to the ADF/cofilin family, besides their actions in actin turnover. The latter part discusses an array of diverse processes, which include regulation of intracellular contractility, maintenance of nuclear integrity, transcriptional regulation, nuclear actin monomer transfer, apoptosis and lipid metabolism. Some of these could, of course, be indirect consequences of actin treadmilling functions, and this is discussed. PMID:27505888

  18. Activation Mechanism of LRRK2 and Its Cellular Functions in Parkinson's Disease

    PubMed Central

    Rosenbusch, Katharina E.; Kortholt, Arjan

    2016-01-01

    Human LRRK2 (Leucine-Rich Repeat Kinase 2) has been associated with both familial and idiopathic Parkinson's disease (PD). Although several LRRK2 mediated pathways and interaction partners have been identified, the cellular functions of LRRK2 and LRRK2 mediated progression of PD are still only partially understood. LRRK2 belongs to the group of Roco proteins which are characterized by the presence of a Ras-like G-domain (Roc), a C-terminal of Roc domain (COR), a kinase, and several protein-protein interaction domains. Roco proteins exhibit a complex activation mechanism involving intramolecular signaling, dimerization, and substrate/effector binding. Importantly, PD mutations in LRRK2 have been linked to a decreased GTPase and impaired kinase activity, thus providing putative therapeutic targets. To fully explore these potential targets it will be crucial to understand the function and identify the pathways responsible for LRRK2-linked PD. Here, we review the recent progress in elucidating the complex LRRK2 activation mechanism, describe the accumulating evidence that link LRRK2-mediated PD to mitochondrial dysfunction and aberrant autophagy, and discuss possible ways for therapeutically targeting LRRK2. PMID:27293958

  19. Insights into the Cellular Function of YhdE, a Nucleotide Pyrophosphatase from Escherichia coli

    PubMed Central

    Jin, Jin; Wu, Ruijuan; Zhu, Jia; Yang, Shaoyuan; Lei, Zhen; Wang, Nan; Singh, Vinay K.; Zheng, Jimin; Jia, Zongchao

    2015-01-01

    YhdE, a Maf-like protein in Escherichia coli, exhibits nucleotide pyrophosphatase (PPase) activity, yet its cellular function remains unknown. Here, we characterized the PPase activity of YhdE on dTTP, UTP and TTP and determined two crystal structures of YhdE, revealing ‘closed’ and ‘open’ conformations of an adaptive active site. Our functional studies demonstrated that YhdE retards cell growth by prolonging the lag and log phases, particularly under stress conditions. Morphology studies showed that yhdE-knockout cells transformed the normal rod shape of wild-type cells to a more spherical form, and the cell wall appeared to become more flexible. In contrast, YhdE overexpression resulted in filamentous cells. This study reveals the previously unknown involvement of YhdE in cell growth inhibition under stress conditions, cell-division arrest and cell-shape maintenance, highlighting YhdE’s important role in E. coli cell-cycle checkpoints. PMID:25658941

  20. Molecular and cellular mechanisms for the regulation of ovarian follicular function in cows

    PubMed Central

    SHIMIZU, Takashi

    2016-01-01

    Ovary is an important organ that houses the oocytes (reproductive cell). Oocyte growth depends on the function of follicular cells such as the granulosa and theca cells. Two-cell two gonadotropin systems are associated with oocyte growth and follicular cell functions. In addition to these systems, it is also known that several growth factors regulate oocyte growth and follicular cell functions. Vascular endothelial growth factor (VEGF) is involved in thecal vasculature during follicular development and the suppression of granulosa cell apoptosis. Metabolic factors such as insulin, growth hormone (GH) and insulin-like growth factor 1 (IGF-1) also play critical roles in the process of follicular development and growth. These factors are associated not only with follicular development, but also with follicular cell function. Steroid hormones (estrogens, androgens, and progestins) that are secreted from follicular cells influence the function of the female genital tract and its affect the susceptibility to bacterial infection. This review covers our current understanding of the mechanisms by which gonadotrophins and/or steroid hormones regulate the growth factors in the follicular cells of the bovine ovary. In addition, this review describes the effect of endotoxin on the function of follicular cells. PMID:27097851

  1. Molecular and cellular mechanisms for the regulation of ovarian follicular function in cows.

    PubMed

    Shimizu, Takashi

    2016-08-25

    Ovary is an important organ that houses the oocytes (reproductive cell). Oocyte growth depends on the function of follicular cells such as the granulosa and theca cells. Two-cell two gonadotropin systems are associated with oocyte growth and follicular cell functions. In addition to these systems, it is also known that several growth factors regulate oocyte growth and follicular cell functions. Vascular endothelial growth factor (VEGF) is involved in thecal vasculature during follicular development and the suppression of granulosa cell apoptosis. Metabolic factors such as insulin, growth hormone (GH) and insulin-like growth factor 1 (IGF-1) also play critical roles in the process of follicular development and growth. These factors are associated not only with follicular development, but also with follicular cell function. Steroid hormones (estrogens, androgens, and progestins) that are secreted from follicular cells influence the function of the female genital tract and its affect the susceptibility to bacterial infection. This review covers our current understanding of the mechanisms by which gonadotrophins and/or steroid hormones regulate the growth factors in the follicular cells of the bovine ovary. In addition, this review describes the effect of endotoxin on the function of follicular cells. PMID:27097851

  2. Boron dipyrromethene (BODIPY) functionalized carbon nano-onions for high resolution cellular imaging

    NASA Astrophysics Data System (ADS)

    Bartelmess, Juergen; de Luca, Elisa; Signorelli, Angelo; Baldrighi, Michele; Becce, Michele; Brescia, Rosaria; Nardone, Valentina; Parisini, Emilio; Echegoyen, Luis; Pompa, Pier Paolo; Giordani, Silvia

    2014-10-01

    Carbon nano-onions (CNOs) are an exciting class of carbon nanomaterials, which have recently demonstrated a facile cell-penetration capability. In the present work, highly fluorescent boron dipyrromethene (BODIPY) dyes were covalently attached to the surface of CNOs. The introduction of this new carbon nanomaterial-based imaging platform, made of CNOs and BODIPY fluorophores, allows for the exploration of synergetic effects between the two building blocks and for the elucidation of its performance in biological applications. The high fluorescence intensity exhibited by the functionalized CNOs translates into an excellent in vitro probe for the high resolution imaging of MCF-7 human breast cancer cells. It was also found that the CNOs, internalized by the cells by endocytosis, localized in the lysosomes and did not show any cytotoxic effects. The presented results highlight CNOs as excellent platforms for biological and biomedical studies due to their low toxicity, efficient cellular uptake and low fluorescence quenching of attached probes.Carbon nano-onions (CNOs) are an exciting class of carbon nanomaterials, which have recently demonstrated a facile cell-penetration capability. In the present work, highly fluorescent boron dipyrromethene (BODIPY) dyes were covalently attached to the surface of CNOs. The introduction of this new carbon nanomaterial-based imaging platform, made of CNOs and BODIPY fluorophores, allows for the exploration of synergetic effects between the two building blocks and for the elucidation of its performance in biological applications. The high fluorescence intensity exhibited by the functionalized CNOs translates into an excellent in vitro probe for the high resolution imaging of MCF-7 human breast cancer cells. It was also found that the CNOs, internalized by the cells by endocytosis, localized in the lysosomes and did not show any cytotoxic effects. The presented results highlight CNOs as excellent platforms for biological and biomedical

  3. PTPN13 regulates cellular signalling and β-catenin function during megakaryocytic differentiation.

    PubMed

    Sardina, José L; López-Ruano, Guillermo; Prieto-Bermejo, Rodrigo; Sánchez-Sánchez, Beatriz; Pérez-Fernández, Alejandro; Sánchez-Abarca, Luis Ignacio; Pérez-Simón, José Antonio; Quintales, Luis; Sánchez-Yagüe, Jesús; Llanillo, Marcial; Antequera, Francisco; Hernández-Hernández, Angel

    2014-12-01

    PTPN13 is a high-molecular weight intracellular phosphatase with several isoforms that exhibits a highly modular structure. Although in recent years different roles have been described for PTPN13, we are still far from understanding its function in cell biology. Here we show that PTPN13 expression is activated during megakaryocytic differentiation at the protein and mRNA level. Our results show that the upregulation of PTPN13 inhibits megakaryocytic differentiation, while PTPN13 silencing triggers differentiation. The ability of PTPN13 to alter megakaryocytic differentiation can be explained by its capacity to regulate ERK and STAT signalling. Interestingly, the silencing of β-catenin produced the same effect as PTPN13 downregulation. We demonstrate that both proteins coimmunoprecipitate and colocalise. Moreover, we provide evidence showing that PTPN13 can regulate β-catenin phosphorylation, stability and transcriptional activity. Therefore, the ability of PTPN13 to control megakaryocytic differentiation must be intimately linked to the regulation of β-catenin function. Moreover, our results show for the first time that PTPN13 is stabilised upon Wnt signalling, which makes PTPN13 an important player in canonical Wnt signalling. Our results show that PTPN13 behaves as an important regulator of megakaryocytic differentiation in cell lines and also in murine haematopoietic progenitors. This importance can be explained by the ability of PTPN13 to regulate cellular signalling, and especially through the regulation of β-catenin stability and function. Our results hold true for different megakaryocytic cell lines and also for haematopoietic progenitors, suggesting that these two proteins may play a relevant role during in vivo megakaryopoiesis. PMID:25193362

  4. A functional screen for copper homeostasis genes identifies a pharmacologically tractable cellular system

    PubMed Central

    2014-01-01

    Background Copper is essential for the survival of aerobic organisms. If copper is not properly regulated in the body however, it can be extremely cytotoxic and genetic mutations that compromise copper homeostasis result in severe clinical phenotypes. Understanding how cells maintain optimal copper levels is therefore highly relevant to human health. Results We found that addition of copper (Cu) to culture medium leads to increased respiratory growth of yeast, a phenotype which we then systematically and quantitatively measured in 5050 homozygous diploid deletion strains. Cu’s positive effect on respiratory growth was quantitatively reduced in deletion strains representing 73 different genes, the function of which identify increased iron uptake as a cause of the increase in growth rate. Conversely, these effects were enhanced in strains representing 93 genes. Many of these strains exhibited respiratory defects that were specifically rescued by supplementing the growth medium with Cu. Among the genes identified are known and direct regulators of copper homeostasis, genes required to maintain low vacuolar pH, and genes where evidence supporting a functional link with Cu has been heretofore lacking. Roughly half of the genes are conserved in man, and several of these are associated with Mendelian disorders, including the Cu-imbalance syndromes Menkes and Wilson’s disease. We additionally demonstrate that pharmacological agents, including the approved drug disulfiram, can rescue Cu-deficiencies of both environmental and genetic origin. Conclusions A functional screen in yeast has expanded the list of genes required for Cu-dependent fitness, revealing a complex cellular system with implications for human health. Respiratory fitness defects arising from perturbations in this system can be corrected with pharmacological agents that increase intracellular copper concentrations. PMID:24708151

  5. Cardiac ferroportin regulates cellular iron homeostasis and is important for cardiac function

    PubMed Central

    Lakhal-Littleton, Samira; Wolna, Magda; Carr, Carolyn A.; Miller, Jack J. J.; Christian, Helen C.; Ball, Vicky; Santos, Ana; Diaz, Rebeca; Biggs, Daniel; Stillion, Richard; Holdship, Philip; Clarke, Kieran; Davies, Benjamin; Robbins, Peter A.

    2015-01-01

    Iron is essential to the cell. Both iron deficiency and overload impinge negatively on cardiac health. Thus, effective iron homeostasis is important for cardiac function. Ferroportin (FPN), the only known mammalian iron-exporting protein, plays an essential role in iron homeostasis at the systemic level. It increases systemic iron availability by releasing iron from the cells of the duodenum, spleen, and liver, the sites of iron absorption, recycling, and storage respectively. However, FPN is also found in tissues with no known role in systemic iron handling, such as the heart, where its function remains unknown. To explore this function, we generated mice with a cardiomyocyte-specific deletion of Fpn. We show that these animals have severely impaired cardiac function, with a median survival of 22 wk, despite otherwise unaltered systemic iron status. We then compared their phenotype with that of ubiquitous hepcidin knockouts, a recognized model of the iron-loading disease hemochromatosis. The phenotype of the hepcidin knockouts was far milder, with normal survival up to 12 mo, despite far greater iron loading in the hearts. Histological examination demonstrated that, although cardiac iron accumulates within the cardiomyocytes of Fpn knockouts, it accumulates predominantly in other cell types in the hepcidin knockouts. We conclude, first, that cardiomyocyte FPN is essential for intracellular iron homeostasis and, second, that the site of deposition of iron within the heart determines the severity with which it affects cardiac function. Both findings have significant implications for the assessment and treatment of cardiac complications of iron dysregulation. PMID:25713362

  6. Cardiac ferroportin regulates cellular iron homeostasis and is important for cardiac function.

    PubMed

    Lakhal-Littleton, Samira; Wolna, Magda; Carr, Carolyn A; Miller, Jack J J; Christian, Helen C; Ball, Vicky; Santos, Ana; Diaz, Rebeca; Biggs, Daniel; Stillion, Richard; Holdship, Philip; Larner, Fiona; Tyler, Damian J; Clarke, Kieran; Davies, Benjamin; Robbins, Peter A

    2015-03-10

    Iron is essential to the cell. Both iron deficiency and overload impinge negatively on cardiac health. Thus, effective iron homeostasis is important for cardiac function. Ferroportin (FPN), the only known mammalian iron-exporting protein, plays an essential role in iron homeostasis at the systemic level. It increases systemic iron availability by releasing iron from the cells of the duodenum, spleen, and liver, the sites of iron absorption, recycling, and storage respectively. However, FPN is also found in tissues with no known role in systemic iron handling, such as the heart, where its function remains unknown. To explore this function, we generated mice with a cardiomyocyte-specific deletion of Fpn. We show that these animals have severely impaired cardiac function, with a median survival of 22 wk, despite otherwise unaltered systemic iron status. We then compared their phenotype with that of ubiquitous hepcidin knockouts, a recognized model of the iron-loading disease hemochromatosis. The phenotype of the hepcidin knockouts was far milder, with normal survival up to 12 mo, despite far greater iron loading in the hearts. Histological examination demonstrated that, although cardiac iron accumulates within the cardiomyocytes of Fpn knockouts, it accumulates predominantly in other cell types in the hepcidin knockouts. We conclude, first, that cardiomyocyte FPN is essential for intracellular iron homeostasis and, second, that the site of deposition of iron within the heart determines the severity with which it affects cardiac function. Both findings have significant implications for the assessment and treatment of cardiac complications of iron dysregulation. PMID:25713362

  7. Tumor suppressor BTG1 promotes PRMT1-mediated ATF4 function in response to cellular stress

    PubMed Central

    Tijchon, Esther; van Ingen Schenau, Dorette; van Emst, Liesbeth; Levers, Marloes; Palit, Sander A.L.; Rodenbach, Caroline; Poelmans, Geert; Hoogerbrugge, Peter M.; Shan, Jixiu; Kilberg, Michael S.; Scheijen, Blanca; van Leeuwen, Frank N.

    2016-01-01

    Cancer cells are frequently exposed to physiological stress conditions such as hypoxia and nutrient limitation. Escape from stress-induced apoptosis is one of the mechanisms used by malignant cells to survive unfavorable conditions. B-cell Translocation Gene 1 (BTG1) is a tumor suppressor that is frequently deleted in acute lymphoblastic leukemia and recurrently mutated in diffuse large B cell lymphoma. Moreover, low BTG1 expression levels have been linked to poor outcome in several solid tumors. How loss of BTG1 function contributes to tumor progression is not well understood. Here, using Btg1 knockout mice, we demonstrate that loss of Btg1 provides a survival advantage to primary mouse embryonic fibroblasts (MEFs) under stress conditions. This pro-survival effect involves regulation of Activating Transcription Factor 4 (ATF4), a key mediator of cellular stress responses. We show that BTG1 interacts with ATF4 and positively modulates its activity by recruiting the protein arginine methyl transferase PRMT1 to methylate ATF4 on arginine residue 239. We further extend these findings to B-cell progenitors, by showing that loss of Btg1 expression enhances stress adaptation of mouse bone marrow-derived B cell progenitors. In conclusion, we have identified the BTG1/PRMT1 complex as a new modifier of ATF4 mediated stress responses. PMID:26657730

  8. Elucidating the Function of Penetratin and a Static Magnetic Field in Cellular Uptake of Magnetic Nanoparticles

    PubMed Central

    Chaudhary, Suman; Smith, Carol Anne; del Pino, Pablo; de la Fuente, Jesus M.; Mullin, Margaret; Hursthouse, Andrew; Stirling, David; Berry, Catherine C.

    2013-01-01

    Nanotechnology plays an increasingly important role in the biomedical arena. In particular, magnetic nanoparticles (mNPs) have become important tools in molecular diagnostics, in vivo imaging and improved treatment of disease, with the ultimate aim of producing a more theranostic approach. Due to their small sizes, the nanoparticles can cross most of the biological barriers such as the blood vessels and the blood brain barrier, thus providing ubiquitous access to most tissues. In all biomedical applications maximum nanoparticle uptake into cells is required. Two promising methods employed to this end include functionalization of mNPs with cell-penetrating peptides to promote efficient translocation of cargo into the cell and the use of external magnetic fields for enhanced delivery. This study aimed to compare the effect of both penetratin and a static magnetic field with regards to the cellular uptake of 200 nm magnetic NPs and determine the route of uptake by both methods. Results demonstrated that both techniques increased particle uptake, with penetratin proving more cell specific. Clathrin- medicated endocytosis appeared to be responsible for uptake as shown via PCR and western blot, with Pitstop 2 (known to selectively block clathrin formation) blocking particle uptake. Interestingly, it was further shown that a magnetic field was able to reverse or overcome the blocking, suggesting an alternative route of uptake. PMID:24275948

  9. Conserved cellular function and stress-mediated regulation among members of the proteolipid protein family.

    PubMed

    Fernández, María E; Alfonso, Julieta; Brocco, Marcela A; Frasch, Alberto C

    2010-05-01

    Chronic stress causes morphological alterations in the hippocampus of rodents and tree shrews, including atrophy of CA3 dendrites and loss of synapses. The molecular mechanisms underlying these structural changes remain largely unknown. We have previously identified M6a as a stress responsive gene and shown that M6a is involved in filopodium/spine outgrowth and, likely, synapse formation. M6a belongs to the proteolipid protein (PLP) family, all of their members having four transmembrane domains that allow their localization at the plasma membrane. In the present work, we analyzed other members of this family, the closely related M6b as well as PLP and its splice variant DM20. We found that chronic restraint stress in mice reduces M6b and DM20, but not PLP, mRNA levels in the hippocampus. In addition, M6b and DM20, but again not PLP, induce filopodium formation in primary cultures of hippocampal neurons. Several M6b protein isoforms were studied, all of them having similar effects except for the one lacking the transmembrane domains. Our results reveal a conserved cellular function and a stress-mediated regulation among members of the proteolipid protein family, suggesting an involvement of proteolipid proteins in the stress response. PMID:19937804

  10. Role of cellular prion proteins in the function of macrophages and dendritic cells.

    PubMed

    Nitta, Kayako; Sakudo, Akikazu; Masuyama, Jun; Xue, Guangai; Sugiura, Katsuaki; Onodera, Takashi

    2009-01-01

    The cellular isoform of prion proteins (PrPC) is expressed in hematopoietic stem cells, granulocytes, T and B lymphocyte natural killer cells, platelets, monocytes, dendritic cells, and follicular dendritic cells, which may act as carrier cells for the spread of its abnormal isoform (PrPSc) before manifesting transmissible spongiform encephalopathies (TSEs). In particular, macrophages and dendritic cells seem to be involved in the replication of PrPSc after ingestion. In addition, information on the role of PrPC during phagocytotic activity in these cells has been obtained. A recent study showed that resident macrophages from ZrchI PrP gene (Prnp)-deficient (Prnp-/-) mice show augmented phagocytotic activity compared to Prnp+/+ counterparts. In contrast, our study suggests that Rikn Prnp-/- peritoneal macrophages show pseudopodium extension arrest and up-regulation of phagocytotic activity compared to Prnp+/+ cells. Although reports regarding phagocytotic activity in resident and peritoneal macrophages are inconsistent between ZrchI and Rikn Prnp-/- mice, it seems plausible that PrPC in macrophages could contribute to maintain the immunological environment. This review will introduce the recent progress in understanding the functions of PrPC in macrophages and dendritic cells under physiological conditions and its involvement in the pathogenesis of prion diseases. PMID:19275736

  11. Cellular functions of genetically imprinted genes in human and mouse as annotated in the gene ontology.

    PubMed

    Hamed, Mohamed; Ismael, Siba; Paulsen, Martina; Helms, Volkhard

    2012-01-01

    By analyzing the cellular functions of genetically imprinted genes as annotated in the Gene Ontology for human and mouse, we found that imprinted genes are often involved in developmental, transport and regulatory processes. In the human, paternally expressed genes are enriched in GO terms related to the development of organs and of anatomical structures. In the mouse, maternally expressed genes regulate cation transport as well as G-protein signaling processes. Furthermore, we investigated if imprinted genes are regulated by common transcription factors. We identified 25 TF families that showed an enrichment of binding sites in the set of imprinted genes in human and 40 TF families in mouse. In general, maternally and paternally expressed genes are not regulated by different transcription factors. The genes Nnat, Klf14, Blcap, Gnas and Ube3a contribute most to the enrichment of TF families. In the mouse, genes that are maternally expressed in placenta are enriched for AP1 binding sites. In the human, we found that these genes possessed binding sites for both, AP1 and SP1. PMID:23226257

  12. Effect of human immunodeficiency virus type 1 protein R (vpr) gene expression on basic cellular function of fission yeast Schizosaccharomyces pombe.

    PubMed Central

    Zhao, Y; Cao, J; O'Gorman, M R; Yu, M; Yogev, R

    1996-01-01

    The human immunodeficiency virus type 1 (HIV-1) Vpr protein affects cell morphology and prevents proliferation of human cells by induction of cell cycle G2 arrest. In this study, we used the fission yeast Schizosaccharomyces pombe as a model system to investigate the cellular effects of HIV-1 vpr gene expression. The vpr gene was cloned into an inducible fission yeast gene expression vector and expressed in wild-type S. pombe cells, and using these cells, we were able to demonstrate the specific Vpr-induced effects by induction and suppression of vpr gene expression. Induction of HIV-1 vpr gene expression affected S. pombe at the colonial, cellular, and molecular levels. Specifically, Vpr induced small-colony formation, polymorphic cells, growth delay, and cell cycle G2 arrest. Additionally, Vpr-induced G2 arrest appeared to be independent of cell size and morphological changes. The cell cycle G2 arrest correlated with increased phosphorylation of p34cdc2, suggesting negative regulation of mitosis by HIV-1 Vpr. Treatment of Vpr-induced cell with a protein phosphatase inhibitor, okadaic acid, transiently suppressed cell cycle arrest and morphological changes. This observation implicates possible involvement of protein phosphatase(s) in the effects of Vpr. Together, these data showed that the HIV-1 Vpr-induced cellular changes in S. pombe are similar to those observed in human cells. Therefore, the S. pombe system is suited for further investigation of the HIV-1 vpr gene functions. PMID:8709199

  13. Cellular interference in craniofrontonasal syndrome: males mosaic for mutations in the X-linked EFNB1 gene are more severely affected than true hemizygotes

    PubMed Central

    Twigg, Stephen R.F.; Babbs, Christian; van den Elzen, Marijke E.P.; Goriely, Anne; Taylor, Stephen; McGowan, Simon J.; Giannoulatou, Eleni; Lonie, Lorne; Ragoussis, Jiannis; Akha, Elham Sadighi; Knight, Samantha J.L.; Zechi-Ceide, Roseli M.; Hoogeboom, Jeannette A.M.; Pober, Barbara R.; Toriello, Helga V.; Wall, Steven A.; Rita Passos-Bueno, M.; Brunner, Han G.; Mathijssen, Irene M.J.; Wilkie, Andrew O.M.

    2013-01-01

    Craniofrontonasal syndrome (CFNS), an X-linked disorder caused by loss-of-function mutations of EFNB1, exhibits a paradoxical sex reversal in phenotypic severity: females characteristically have frontonasal dysplasia, craniosynostosis and additional minor malformations, but males are usually more mildly affected with hypertelorism as the only feature. X-inactivation is proposed to explain the more severe outcome in heterozygous females, as this leads to functional mosaicism for cells with differing expression of EPHRIN-B1, generating abnormal tissue boundaries—a process that cannot occur in hemizygous males. Apparently challenging this model, males occasionally present with a more severe female-like CFNS phenotype. We hypothesized that such individuals might be mosaic for EFNB1 mutations and investigated this possibility in multiple tissue samples from six sporadically presenting males. Using denaturing high performance liquid chromatography, massively parallel sequencing and multiplex-ligation-dependent probe amplification (MLPA) to increase sensitivity above standard dideoxy sequencing, we identified mosaic mutations of EFNB1 in all cases, comprising three missense changes, two gene deletions and a novel point mutation within the 5′ untranslated region (UTR). Quantification by Pyrosequencing and MLPA demonstrated levels of mutant cells between 15 and 69%. The 5′ UTR variant mutates the stop codon of a small upstream open reading frame that, using a dual-luciferase reporter construct, was demonstrated to exacerbate interference with translation of the wild-type protein. These results demonstrate a more severe outcome in mosaic than in constitutionally deficient males in an X-linked dominant disorder and provide further support for the cellular interference mechanism, normally related to X-inactivation in females. PMID:23335590

  14. Membrane Transporters for Sulfated Steroids in the Human Testis - Cellular Localization, Expression Pattern and Functional Analysis

    PubMed Central

    Wapelhorst, Britta; Grosser, Gary; Günther, Sabine; Alber, Jörg; Döring, Barbara; Kliesch, Sabine; Weidner, Wolfgang; Galuska, Christina E.; Hartmann, Michaela F.; Wudy, Stefan A.; Bergmann, Martin; Geyer, Joachim

    2013-01-01

    Sulfated steroid hormones are commonly considered to be biologically inactive metabolites, but may be reactivated by the steroid sulfatase into biologically active free steroids, thereby having regulatory function via nuclear androgen and estrogen receptors which are widespread in the testis. However, a prerequisite for this mode of action would be a carrier-mediated import of the hydrophilic steroid sulfate molecules into specific target cells in reproductive tissues such as the testis. In the present study we detected predominant expression of the Sodium-dependent Organic Anion Transporter (SOAT), the Organic Anion Transporting Polypeptide 6A1, and the Organic Solute Carrier Partner 1 in human testis biopsies. All of these showed significantly lower or even absent mRNA expression in severe disorders of spermatogenesis (arrest at the level of spermatocytes or spermatogonia, Sertoli cell only syndrome). Only SOAT was significantly lower expressed in biopsies showing hypospermatogenesis. By use of immunohistochemistry SOAT was localized to germ cells at various stages in human testis biopsies showing normal spermatogenesis. SOAT immunoreactivity was detected in zygotene primary spermatocytes of stage V, pachytene spermatocytes of all stages (I–V), secondary spermatocytes of stage VI, and round spermatids (step 1 and step 2) in stages I and II. Furthermore, SOAT transport function for steroid sulfates was analyzed with a novel liquid chromatography tandem mass spectrometry procedure capable of profiling steroid sulfate molecules from cell lysates. With this technique, the cellular inward-directed SOAT transport was verified for the established substrates dehydroepiandrosterone sulfate and estrone-3-sulfate. Additionally, β-estradiol-3-sulfate and androstenediol-3-sulfate were identified as novel SOAT substrates. PMID:23667501

  15. Glycosaminoglycan-functionalized poly-lactide-co-glycolide nanoparticles: synthesis, characterization, cytocompatibility, and cellular uptake

    PubMed Central

    Lamichhane, Surya P; Arya, Neha; Ojha, Nirdesh; Kohler, Esther; Shastri, V Prasad

    2015-01-01

    The efficient delivery of chemotherapeutics to the tumor via nanoparticle (NP)-based delivery systems remains a significant challenge. This is compounded by the fact that the tumor is highly dynamic and complex environment composed of a plurality of cell types and extracellular matrix. Since glycosaminoglycan (GAG) production is altered in many diseases (or pathologies), NPs bearing GAG moieties on the surface may confer some unique advantages in interrogating the tumor microenvironment. In order to explore this premise, in the study reported here poly-lactide-co-glycolide (PLGA) NPs in the range of 100–150 nm bearing various proteoglycans were synthesized by a single-step nanoprecipitation and characterized. The surface functionalization of the NPs with GAG moieties was verified using zeta potential measurements and X-ray photoelectron spectroscopy. To establish these GAG-bearing NPs as carriers of therapeutics, cellular toxicity assays were undertaken in lung epithelial adenocarcinoma (A549) cells, human pulmonary microvascular endothelial cells (HPMEC), and renal proximal tubular epithelial cells. In general NPs were well tolerated over a wide concentration range (100–600 μg/mL) by all cell types and were taken up to appreciable extents without any adverse cell response in A549 cells and HPMEC. Further, GAG-functionalized PLGA NPs were taken up to different extents in A459 cells and HPMEC. In both cell systems, the uptake of heparin-modified NPs was diminished by 50%–65% in comparison to that of unmodified PLGA. Interestingly, the uptake of chondroitin sulfate NPs was the highest in both cell systems with 40%–60% higher uptake when compared with that of PLGA, and this represented an almost twofold difference over heparin-modified NPs. These findings suggest that GAG modification can be explored as means of changing the uptake behavior of PLGA NPs and these NP systems have potential in cancer therapy. PMID:25632234

  16. Molecular characterization and functions of zebrafish ABCC2 in cellular efflux of heavy metals.

    PubMed

    Long, Yong; Li, Qing; Zhong, Shan; Wang, Youhui; Cui, Zongbin

    2011-05-01

    Multidrug-resistance associated protein 2 (MRP2/ABCC2) plays crucial roles in bile formation and detoxification by transporting a wide variety of endogenous compounds and xenobiotics, but its functions in zebrafish (Danio rerio) remain to be characterized. In this study, we obtained the full-length cDNA of zebrafish abcc2, analyzed its expression in developing embryos and adult tissues, investigated its transcriptional response to heavy metals, and evaluated its roles in efflux of heavy metals including cadmium, mercury and lead. Zebrafish abcc2 gene is located on chromosome 13 and composed of 32 exons. The deduced polypeptide of zebrafish ABCC2 consists of 1567 amino acids and possesses most of functional domains and critical residues defined in human ABCC2. Zebrafish abcc2 gene is not maternally expressed and its earliest expression was detected in embryos at 72hpf. In larval zebrafish, abcc2 gene was found to be exclusively expressed in liver, intestine and pronephric tubules. In adult zebrafish, the highest expression of abcc2 gene was found in intestine followed by those in liver and kidney, while relative low expression was detected in brain and muscle. Expression of abcc2 in excretory organs including kidney, liver and intestine of zebrafish larvae was induced by exposure to 0.5μM mercury or 5μM lead. Moreover, exposure to 0.125-1μM of mercury or lead also significantly induced abcc2 expression in these excretory organs of adult zebrafish. Furthermore, overexpression of zebrafish ABCC2 in ZF4 cells and zebrafish embryos decreased the cellular accumulation of heavy metals including cadmium, mercury and lead as determined by MRE (metal responsive element)- or EPRE (electrophile response element)-driven luciferase reporters and atomic absorption spectrometry. These results suggest that zebrafish ABCC2/MRP2 is capable of effluxing heavy metals from cells and may play important roles in the detoxification of toxic metals. PMID:21266201

  17. Fatty Acid Ethyl Esters Disrupt Neonatal Alveolar Macrophage Mitochondria and Derange Cellular Functioning

    PubMed Central

    Mohan, Sowmya S; Ping, Xiao Du; Harris, Frank L; Ronda, Necol J; Brown, Lou Ann S; Gauthier, Theresa W

    2015-01-01

    Background Chronic alcohol exposure alters the function of alveolar macrophages (AM), impairing immune defenses in both adult and neonatal lungs. Fatty acid ethyl esters (FAEEs) are biological markers of prenatal alcohol exposure in newborns. FAEEs contribute to alcohol-induced mitochondrial (MT) damage in multiple organs. We hypothesized that in utero ethanol exposure would increase FAEEs in the neonatal lung and that direct exposure of neonatal AM to FAEEs would contribute to MT injury and cellular dysfunction. Methods FAEEs were measured in neonatal guinea pig lungs after ± in utero ethanol exposure via gas chromatography/mass spectrometry. The NR8383 cell line and freshly isolated neonatal guinea pig AM were exposed to ethyl oleate (EO) in vitro. MT membrane potential, MT reactive oxygen species generation (mROS), phagocytosis, and apoptosis were evaluated after exposure to EO ± the MT-specific antioxidant mito-TEMPO (mitoT) or ± the pan-caspase inhibitor Z-VAD-FMK. Whole lung FAEEs were compared using the Mann–Whitney U-test. Cellular results were analyzed using 1-way analysis of variance, followed by the Student–Newman–Keuls Method for post hoc comparisons. Results In utero ethanol significantly increased ethyl linoleate and the combinations of ethyl oleate + linoleate + linolenate (OLL), and OLL + stearate in the neonatal lung. In vitro EO caused significant MT dysfunction in both NR8383 and primary neonatal AM, as indicated by increased mROS and loss of MT membrane potential. Impaired phagocytosis and apoptosis were significantly increased in both the cell line and primary AM after EO exposure. MitoT conferred significant but only partial protection against EO-induced MT injury, as did caspase inhibition with Z-VAD-FMK. Conclusions In utero ethanol exposure increased FAEEs in the neonatal guinea pig lung. Direct exposure to the FAEE EO significantly contributed to AM dysfunction, in part via oxidant injury to the MT and in part via secondary

  18. PHYSIOLOGY AND ENDOCRINOLOGY SYMPOSIUM: Cellular and molecular mechanisms of heat stress related to bovine ovarian function.

    PubMed

    Roth, Z

    2015-05-01

    In light of the intensive genetic selection for high milk production and the onset of global warming, it seems that the reduced fertility of lactating cows during the summer will worsen in coming years. Although not entirely clear, the mechanism appears to be multifactorial in nature. It includes alterations in follicular development, depression of follicular dominance, and impairment of steroidogenesis and gonadotropin secretion. Heat-induced perturbations in the physiology of the follicle-enclosed oocyte have also been documented, expressed by impaired cleavage rate and reduced developmental competence. With respect to the oocyte, alterations include an increase in PUFA in the membrane, reactive oxygen species, ceramide formation and caspase activity, and induction of apoptosis via the sphingomyelin and/or mitochondrial pathways. New insight into cellular and molecular alterations has revealed that heat induces perturbations in both nuclear and cytoplasmic maturation events, such as resumption of meiosis, metaphase II plate formation, cytoskeleton rearrangement, and translocation of cortical granules. Alterations in mitochondrial distribution (i.e., low proportion of category I mitochondria) and function (i.e., low membrane potential) have recently been reported for oocytes collected during the summer. These were associated with impaired expression of both nuclear (succinate dehydrogenase subunit [SDHD], adenosine triphosphate [ATP] synthase subunit beta [ATP5B]), mitochondrially NADH dehydrogenase subunit 2 (ND2), and mitochondiral (cytochrome c oxidase subunit II [MT-CO2] and cytochrome b [MT-CYB]) genes that are crucial in the mitochondrial respiratory chain. In addition, season-induced alteration in the stored maternal mRNA has been documented, expressed by reduced transcript levels (oocyte maturation factor MOS [C-MOS], growth differentiation factor 9 [GDF9], POU domain class 5 transcription factor 1 [POU5F1], and glyceraldehyde-3-phosphate dehydrogenase

  19. Functional Contributions of Strong and Weak Cellular Oscillators to Synchrony and Light-shifted Phase Dynamics.

    PubMed

    Roberts, Logan; Leise, Tanya L; Welsh, David K; Holmes, Todd C

    2016-08-01

    Light is the primary signal that calibrates circadian neural circuits and thus coordinates daily physiological and behavioral rhythms with solar entrainment cues. Drosophila and mammalian circadian circuits consist of diverse populations of cellular oscillators that exhibit a wide range of dynamic light responses, periods, phases, and degrees of synchrony. How heterogeneous circadian circuits can generate robust physiological rhythms while remaining flexible enough to respond to synchronizing stimuli has long remained enigmatic. Cryptochrome is a short-wavelength photoreceptor that is endogenously expressed in approximately half of Drosophila circadian neurons. In a previous study, physiological light response was measured using real-time bioluminescence recordings in Drosophila whole-brain explants, which remain intrinsically light-sensitive. Here we apply analysis of real-time bioluminescence experimental data to show detailed dynamic ensemble representations of whole circadian circuit light entrainment at single neuron resolution. Organotypic whole-brain explants were either maintained in constant darkness (DD) for 6 days or exposed to a phase-advancing light pulse on the second day. We find that stronger circadian oscillators support robust overall circuit rhythmicity in DD, whereas weaker oscillators can be pushed toward transient desynchrony and damped amplitude to facilitate a new state of phase-shifted network synchrony. Additionally, we use mathematical modeling to examine how a network composed of distinct oscillator types can give rise to complex dynamic signatures in DD conditions and in response to simulated light pulses. Simulations suggest that complementary coupling mechanisms and a combination of strong and weak oscillators may enable a robust yet flexible circadian network that promotes both synchrony and entrainment. A more complete understanding of how the properties of oscillators and their signaling mechanisms facilitate their distinct roles

  20. The UL24 protein of herpes simplex virus 1 affects the sub-cellular distribution of viral glycoproteins involved in fusion

    SciTech Connect

    Ben Abdeljelil, Nawel; Rochette, Pierre-Alexandre; Pearson, Angela

    2013-09-15

    Mutations in UL24 of herpes simplex virus type 1 can lead to a syncytial phenotype. We hypothesized that UL24 affects the sub-cellular distribution of viral glycoproteins involved in fusion. In non-immortalized human foreskin fibroblasts (HFFs) we detected viral glycoproteins B (gB), gD, gH and gL present in extended blotches throughout the cytoplasm with limited nuclear membrane staining; however, in HFFs infected with a UL24-deficient virus (UL24X), staining for the viral glycoproteins appeared as long, thin streaks running across the cell. Interestingly, there was a decrease in co-localized staining of gB and gD with F-actin at late times in UL24X-infected HFFs. Treatment with chemical agents that perturbed the actin cytoskeleton hindered the formation of UL24X-induced syncytia in these cells. These data support a model whereby the UL24 syncytial phenotype results from a mislocalization of viral glycoproteins late in infection. - Highlights: • UL24 affects the sub-cellular distribution of viral glycoproteins required for fusion. • Sub-cellular distribution of viral glycoproteins varies in cell-type dependent manner. • Drugs targeting actin microfilaments affect formation of UL24-related syncytia in HFFs.

  1. Proteomic Profiling in the Brain of CLN1 Disease Model Reveals Affected Functional Modules.

    PubMed

    Tikka, Saara; Monogioudi, Evanthia; Gotsopoulos, Athanasios; Soliymani, Rabah; Pezzini, Francesco; Scifo, Enzo; Uusi-Rauva, Kristiina; Tyynelä, Jaana; Baumann, Marc; Jalanko, Anu; Simonati, Alessandro; Lalowski, Maciej

    2016-03-01

    Neuronal ceroid lipofuscinoses (NCL) are the most commonly inherited progressive encephalopathies of childhood. Pathologically, they are characterized by endolysosomal storage with different ultrastructural features and biochemical compositions. The molecular mechanisms causing progressive neurodegeneration and common molecular pathways linking expression of different NCL genes are largely unknown. We analyzed proteome alterations in the brains of a mouse model of human infantile CLN1 disease-palmitoyl-protein thioesterase 1 (Ppt1) gene knockout and its wild-type age-matched counterpart at different stages: pre-symptomatic, symptomatic and advanced. For this purpose, we utilized a combination of laser capture microdissection-based quantitative liquid chromatography tandem mass spectrometry (MS) and matrix-assisted laser desorption/ionization time-of-flight MS imaging to quantify/visualize the changes in protein expression in disease-affected brain thalamus and cerebral cortex tissue slices, respectively. Proteomic profiling of the pre-symptomatic stage thalamus revealed alterations mostly in metabolic processes and inhibition of various neuronal functions, i.e., neuritogenesis. Down-regulation in dynamics associated with growth of plasma projections and cellular protrusions was further corroborated by findings from RNA sequencing of CLN1 patients' fibroblasts. Changes detected at the symptomatic stage included: mitochondrial functions, synaptic vesicle transport, myelin proteome and signaling cascades, such as RhoA signaling. Considerable dysregulation of processes related to mitochondrial cell death, RhoA/Huntington's disease signaling and myelin sheath breakdown were observed at the advanced stage of the disease. The identified changes in protein levels were further substantiated by bioinformatics and network approaches, immunohistochemistry on brain tissues and literature knowledge, thus identifying various functional modules affected in the CLN1 childhood

  2. Biophysical properties of dermal building-blocks affects extra cellular matrix assembly in 3D endogenous macrotissue.

    PubMed

    Urciuolo, F; Garziano, A; Imparato, G; Panzetta, V; Fusco, S; Casale, C; Netti, P A

    2016-03-01

    The fabrication of functional tissue units is one of the major challenges in tissue engineering due to their in vitro use in tissue-on-chip systems, as well as in modular tissue engineering for the construction of macrotissue analogs. In this work, we aim to engineer dermal tissue micromodules obtained by culturing human dermal fibroblasts into porous gelatine microscaffold. We proved that such stromal cells coupled with gelatine microscaffolds are able to synthesize and to assemble an endogenous extracellular matrix (ECM) resulting in tissue micromodules, which evolve their biophysical features over the time. In particular, we found a time-dependent variation of oxygen consumption kinetic parameters, of newly formed ECM stiffness and of micromodules self-aggregation properties. As consequence when used as building blocks to fabricate larger tissues, the initial tissue micromodules state strongly affects the ECM organization and maturation in the final macrotissue. Such results highlight the role of the micromodules properties in controlling the formation of three-dimensional macrotissue in vitro, defining an innovative design criterion for selecting tissue-building blocks for modular tissue engineering. PMID:26824879

  3. Calcium and ascorbic acid affect cellular structure and water mobility in apple tissue during osmotic dehydration in sucrose solutions.

    PubMed

    Mauro, Maria A; Dellarosa, Nicolò; Tylewicz, Urszula; Tappi, Silvia; Laghi, Luca; Rocculi, Pietro; Rosa, Marco Dalla

    2016-03-15

    The effects of the addition of calcium lactate and ascorbic acid to sucrose osmotic solutions on cell viability and microstructure of apple tissue were studied. In addition, water distribution and mobility modification of the different cellular compartments were observed. Fluorescence microscopy, light microscopy and time domain nuclear magnetic resonance (TD-NMR) were respectively used to evaluate cell viability and microstructural changes during osmotic dehydration. Tissues treated in a sucrose-calcium lactate-ascorbic acid solution did not show viability. Calcium lactate had some effects on cell walls and membranes. Sucrose solution visibly preserved the protoplast viability and slightly influenced the water distribution within the apple tissue, as highlighted by TD-NMR, which showed higher proton intensity in the vacuoles and lower intensity in cytoplasm-free spaces compared to other treatments. The presence of ascorbic acid enhanced calcium impregnation, which was associated with permeability changes of the cellular wall and membranes. PMID:26575708

  4. Functional Divergence of Hsp90 Genetic Interactions in Biofilm and Planktonic Cellular States

    PubMed Central

    Cowen, Leah E.

    2015-01-01

    Candida albicans is among the most prevalent opportunistic fungal pathogens. Its capacity to cause life-threatening bloodstream infections is associated with the ability to form biofilms, which are intrinsically drug resistant reservoirs for dispersal. A key regulator of biofilm drug resistance and dispersal is the molecular chaperone Hsp90, which stabilizes many signal transducers. We previously identified 226 C. albicans Hsp90 genetic interactors under planktonic conditions, of which 56 are involved in transcriptional regulation. Six of these transcriptional regulators have previously been implicated in biofilm formation, suggesting that Hsp90 genetic interactions identified in planktonic conditions may have functional significance in biofilms. Here, we explored the relationship between Hsp90 and five of these transcription factor genetic interactors: BCR1, MIG1, TEC1, TUP1, and UPC2. We deleted each transcription factor gene in an Hsp90 conditional expression strain, and assessed biofilm formation and morphogenesis. Strikingly, depletion of Hsp90 conferred no additional biofilm defect in the mutants. An interaction was observed in which deletion of BCR1 enhanced filamentation upon reduction of Hsp90 levels. Further, although Hsp90 modulates expression of TEC1, TUP1, and UPC2 in planktonic conditions, it has no impact in biofilms. Lastly, we probed for physical interactions between Hsp90 and Tup1, whose WD40 domain suggests that it might interact with Hsp90 directly. Hsp90 and Tup1 formed a stable complex, independent of temperature or developmental state. Our results illuminate a physical interaction between Hsp90 and a key transcriptional regulator of filamentation and biofilm formation, and suggest that Hsp90 has distinct genetic interactions in planktonic and biofilm cellular states. PMID:26367740

  5. AntiJen: a quantitative immunology database integrating functional, thermodynamic, kinetic, biophysical, and cellular data.

    PubMed

    Toseland, Christopher P; Clayton, Debra J; McSparron, Helen; Hemsley, Shelley L; Blythe, Martin J; Paine, Kelly; Doytchinova, Irini A; Guan, Pingping; Hattotuwagama, Channa K; Flower, Darren R

    2005-10-01

    AntiJen is a database system focused on the integration of kinetic, thermodynamic, functional, and cellular data within the context of immunology and vaccinology. Compared to its progenitor JenPep, the interface has been completely rewritten and redesigned and now offers a wider variety of search methods, including a nucleotide and a peptide BLAST search. In terms of data archived, AntiJen has a richer and more complete breadth, depth, and scope, and this has seen the database increase to over 31,000 entries. AntiJen provides the most complete and up-to-date dataset of its kind. While AntiJen v2.0 retains a focus on both T cell and B cell epitopes, its greatest novelty is the archiving of continuous quantitative data on a variety of immunological molecular interactions. This includes thermodynamic and kinetic measures of peptide binding to TAP and the Major Histocompatibility Complex (MHC), peptide-MHC complexes binding to T cell receptors, antibodies binding to protein antigens and general immunological protein-protein interactions. The database also contains quantitative specificity data from position-specific peptide libraries and biophysical data, in the form of diffusion co-efficients and cell surface copy numbers, on MHCs and other immunological molecules. The uses of AntiJen include the design of vaccines and diagnostics, such as tetramers, and other laboratory reagents, as well as helping parameterize the bioinformatic or mathematical in silico modeling of the immune system. The database is accessible from the URL: http://www.jenner.ac.uk/antijen. PMID:16305757

  6. Perturbing the Cellular Levels of Steroid Receptor Coactivator-2 Impairs Murine Endometrial Function

    PubMed Central

    Szwarc, Maria M.; Kommagani, Ramakrishna; Jeong, Jae-Wook; Wu, San-Pin; Tsai, Sophia Y.; Tsai, Ming-Jer; O’Malley, Bert W.; DeMayo, Francesco J.; Lydon, John P.

    2014-01-01

    As pleiotropic coregulators, members of the p160/steroid receptor coactivator (SRC) family control a broad spectrum of transcriptional responses that underpin a diverse array of physiological and pathophysiological processes. Because of their potent coregulator properties, strict controls on SRC expression levels are required to maintain normal tissue functionality. Accordingly, an unwarranted increase in the cellular levels of SRC members has been causally linked to the initiation and/or progression of a number of clinical disorders. Although knockout mouse models have underscored the critical non-redundant roles for each SRC member in vivo, there are surprisingly few mouse models that have been engineered to overexpress SRCs. This deficiency is significant since SRC involvement in many of these disorders is based on unscheduled increases in the levels (rather than the absence) of SRC expression. To address this deficiency, we used recent mouse technology that allows for the targeted expression of human SRC-2 in cells which express the progesterone receptor. Through cre-loxP recombination driven by the endogenous progesterone receptor promoter, a marked elevation in expression levels of human SRC-2 was achieved in endometrial cells that are positive for the progesterone receptor. As a result of this increase in coregulator expression, female mice are severely subfertile due to a dysfunctional uterus, which exhibits a hypersensitivity to estrogen exposure. Our findings strongly support the proposal from clinical observations that increased levels of SRC-2 are causal for a number of endometrial disorders which compromise fertility. Future studies will use this mouse model to decipher the molecular mechanisms that underpin the endometrial defect. We believe such mechanistic insight may provide new molecular descriptors for diagnosis, prognosis, and/or therapy in the clinical management of female infertility. PMID:24905738

  7. Quantitative metric profiles capture three-dimensional temporospatial architecture to discriminate cellular functional states

    PubMed Central

    2011-01-01

    Background Computational analysis of tissue structure reveals sub-visual differences in tissue functional states by extracting quantitative signature features that establish a diagnostic profile. Incomplete and/or inaccurate profiles contribute to misdiagnosis. Methods In order to create more complete tissue structure profiles, we adapted our cell-graph method for extracting quantitative features from histopathology images to now capture temporospatial traits of three-dimensional collagen hydrogel cell cultures. Cell-graphs were proposed to characterize the spatial organization between the cells in tissues by exploiting graph theory wherein the nuclei of the cells constitute the nodes and the approximate adjacency of cells are represented with edges. We chose 11 different cell types representing non-tumorigenic, pre-cancerous, and malignant states from multiple tissue origins. Results We built cell-graphs from the cellular hydrogel images and computed a large set of features describing the structural characteristics captured by the graphs over time. Using three-mode tensor analysis, we identified the five most significant features (metrics) that capture the compactness, clustering, and spatial uniformity of the 3D architectural changes for each cell type throughout the time course. Importantly, four of these metrics are also the discriminative features for our histopathology data from our previous studies. Conclusions Together, these descriptive metrics provide rigorous quantitative representations of image information that other image analysis methods do not. Examining the changes in these five metrics allowed us to easily discriminate between all 11 cell types, whereas differences from visual examination of the images are not as apparent. These results demonstrate that application of the cell-graph technique to 3D image data yields discriminative metrics that have the potential to improve the accuracy of image-based tissue profiles, and thus improve the detection

  8. Use of a Generalized Additive Model to Investigate Key Abiotic Factors Affecting Microcystin Cellular Quotas in Heavy Bloom Areas of Lake Taihu

    PubMed Central

    Tao, Min; Xie, Ping; Chen, Jun; Qin, Boqiang; Zhang, Dawen; Niu, Yuan; Zhang, Meng; Wang, Qing; Wu, Laiyan

    2012-01-01

    Lake Taihu is the third largest freshwater lake in China and is suffering from serious cyanobacterial blooms with the associated drinking water contamination by microcystin (MC) for millions of citizens. So far, most studies on MCs have been limited to two small bays, while systematic research on the whole lake is lacking. To explain the variations in MC concentrations during cyanobacterial bloom, a large-scale survey at 30 sites across the lake was conducted monthly in 2008. The health risks of MC exposure were high, especially in the northern area. Both Microcystis abundance and MC cellular quotas presented positive correlations with MC concentration in the bloom seasons, suggesting that the toxic risks during Microcystis proliferations were affected by variations in both Microcystis density and MC production per Microcystis cell. Use of a powerful predictive modeling tool named generalized additive model (GAM) helped visualize significant effects of abiotic factors related to carbon fixation and proliferation of Microcystis (conductivity, dissolved inorganic carbon (DIC), water temperature and pH) on MC cellular quotas from recruitment period of Microcystis to the bloom seasons, suggesting the possible use of these factors, in addition to Microcystis abundance, as warning signs to predict toxic events in the future. The interesting relationship between macrophytes and MC cellular quotas of Microcystis (i.e., high MC cellular quotas in the presence of macrophytes) needs further investigation. PMID:22384128

  9. Use of a generalized additive model to investigate key abiotic factors affecting microcystin cellular quotas in heavy bloom areas of Lake Taihu.

    PubMed

    Tao, Min; Xie, Ping; Chen, Jun; Qin, Boqiang; Zhang, Dawen; Niu, Yuan; Zhang, Meng; Wang, Qing; Wu, Laiyan

    2012-01-01

    Lake Taihu is the third largest freshwater lake in China and is suffering from serious cyanobacterial blooms with the associated drinking water contamination by microcystin (MC) for millions of citizens. So far, most studies on MCs have been limited to two small bays, while systematic research on the whole lake is lacking. To explain the variations in MC concentrations during cyanobacterial bloom, a large-scale survey at 30 sites across the lake was conducted monthly in 2008. The health risks of MC exposure were high, especially in the northern area. Both Microcystis abundance and MC cellular quotas presented positive correlations with MC concentration in the bloom seasons, suggesting that the toxic risks during Microcystis proliferations were affected by variations in both Microcystis density and MC production per Microcystis cell. Use of a powerful predictive modeling tool named generalized additive model (GAM) helped visualize significant effects of abiotic factors related to carbon fixation and proliferation of Microcystis (conductivity, dissolved inorganic carbon (DIC), water temperature and pH) on MC cellular quotas from recruitment period of Microcystis to the bloom seasons, suggesting the possible use of these factors, in addition to Microcystis abundance, as warning signs to predict toxic events in the future. The interesting relationship between macrophytes and MC cellular quotas of Microcystis (i.e., high MC cellular quotas in the presence of macrophytes) needs further investigation. PMID:22384128

  10. Synthesis and characterization of dual-functionalized core-shell fluorescent microspheres for bioconjugation and cellular delivery.

    PubMed

    Behrendt, Jonathan M; Nagel, David; Chundoo, Evita; Alexander, Lois M; Dupin, Damien; Hine, Anna V; Bradley, Mark; Sutherland, Andrew J

    2013-01-01

    The efficient transport of micron-sized beads into cells, via a non-endocytosis mediated mechanism, has only recently been described. As such there is considerable scope for optimization and exploitation of this procedure to enable imaging and sensing applications to be realized. Herein, we report the design, synthesis and characterization of fluorescent microsphere-based cellular delivery agents that can also carry biological cargoes. These core-shell polymer microspheres possess two distinct chemical environments; the core is hydrophobic and can be labeled with fluorescent dye, to permit visual tracking of the microsphere during and after cellular delivery, whilst the outer shell renders the external surfaces of the microspheres hydrophilic, thus facilitating both bioconjugation and cellular compatibility. Cross-linked core particles were prepared in a dispersion polymerization reaction employing styrene, divinylbenzene and a thiol-functionalized co-monomer. These core particles were then shelled in a seeded emulsion polymerization reaction, employing styrene, divinylbenzene and methacrylic acid, to generate orthogonally functionalized core-shell microspheres which were internally labeled via the core thiol moieties through reaction with a thiol reactive dye (DY630-maleimide). Following internal labeling, bioconjugation of green fluorescent protein (GFP) to their carboxyl-functionalized surfaces was successfully accomplished using standard coupling protocols. The resultant dual-labeled microspheres were visualized by both of the fully resolvable fluorescence emissions of their cores (DY630) and shells (GFP). In vitro cellular uptake of these microspheres by HeLa cells was demonstrated conventionally by fluorescence-based flow cytometry, whilst MTT assays demonstrated that 92% of HeLa cells remained viable after uptake. Due to their size and surface functionalities, these far-red-labeled microspheres are ideal candidates for in vitro, cellular delivery of proteins

  11. Cellular and molecular functions of hepatic stellate cells in inflammatory responses and liver immunology

    PubMed Central

    2014-01-01

    The liver is a central immunological organ. Liver resident macrophages, Kupffer cells (KC), but also sinusoidal endothelial cells, dendritic cells (DC) and other immune cells are involved in balancing immunity and tolerance against pathogens, commensals or food antigens. Hepatic stellate cells (HSCs) have been primarily characterized as the main effector cells in liver fibrosis, due to their capacity to transdifferentiate into collagen-producing myofibroblasts (MFB). More recent studies elucidated the fundamental role of HSC in liver immunology. HSC are not only the major storage site for dietary vitamin A (Vit A) (retinol, retinoic acid), which is essential for proper function of the immune system. This pericyte further represents a versatile source of many soluble immunological active factors including cytokines [e.g., interleukin 17 (IL-17)] and chemokines [C-C motif chemokine (ligand) 2 (CCL2)], may act as an antigen presenting cell (APC), and has autophagy activity. Additionally, it responds to many immunological triggers via toll-like receptors (TLR) (e.g., TLR4, TLR9) and transduces signals through pathways and mediators traditionally found in immune cells, including the Hedgehog (Hh) pathway or inflammasome activation. Overall, HSC promote rather immune-suppressive responses in homeostasis, like induction of regulatory T cells (Treg), T cell apoptosis (via B7-H1, PDL-1) or inhibition of cytotoxic CD8 T cells. In conditions of liver injury, HSC are important sensors of altered tissue integrity and initiators of innate immune cell activation. Vice versa, several immune cell subtypes interact directly or via soluble mediators with HSC. Such interactions include the mutual activation of HSC (towards MFB) and macrophages or pro-apoptotic signals from natural killer (NK), natural killer T (NKT) and gamma-delta T cells (γδ T-cells) on activated HSC. Current directions of research investigate the immune-modulating functions of HSC in the environment of liver

  12. Concomitant gastroparesis negatively affects children with functional gallbladder disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of the present study was to determine whether concomitant gastroparesis and biliary dyskinesia (BD) occur in children, and if so, to determine whether concomitant gastroparesis affects clinical outcome in children with BD. We conducted a retrospective chart review of children with BD (ejecti...

  13. Experimentally induced diabetes causes glial activation, glutamate toxicity and cellular damage leading to changes in motor function

    PubMed Central

    Nagayach, Aarti; Patro, Nisha; Patro, Ishan

    2014-01-01

    Behavioral impairments are the most empirical consequence of diabetes mellitus documented in both humans and animal models, but the underlying causes are still poorly understood. As the cerebellum plays a major role in coordination and execution of the motor functions, we investigated the possible involvement of glial activation, cellular degeneration and glutamate transportation in the cerebellum of rats, rendered diabetic by a single injection of streptozotocin (STZ; 45 mg/kg body weight; intraperitoneally). Motor function alterations were studied using Rotarod test (motor coordination) and grip strength (muscle activity) at 2nd, 4th, 6th, 8th, 10th, and 12th week post-diabetic confirmation. Scenario of glial (astroglia and microglia) activation, cell death and glutamate transportation was gaged using immunohistochemistry, histological study and image analysis. Cellular degeneration was clearly demarcated in the diabetic cerebellum. Glial cells were showing sequential and marked activation following diabetes in terms of both morphology and cell number. Bergmann glial cells were hypertrophied and distorted. Active caspase-3 positive apoptotic cells were profoundly present in all three cerebellar layers. Reduced co-labeling of GLT-1 and GFAP revealed the altered glutamate transportation in cerebellum following diabetes. These results, exclusively derived from histology, immunohistochemistry and cellular quantification, provide first insight over the associative reciprocity between the glial activation, cellular degeneration and reduced glutamate transportation, which presumably lead to the behavioral alterations following STZ-induced diabetes. PMID:25400546

  14. Salmonella adhesion, invasion and cellular immune responses are differentially affected by iron concentrations in a combined in vitro gut fermentation-cell model.

    PubMed

    Dostal, Alexandra; Gagnon, Mélanie; Chassard, Christophe; Zimmermann, Michael Bruce; O'Mahony, Liam; Lacroix, Christophe

    2014-01-01

    In regions with a high infectious disease burden, concerns have been raised about the safety of iron supplementation because higher iron concentrations in the gut lumen may increase risk of enteropathogen infection. The aim of this study was to investigate interactions of the enteropathogen Salmonella enterica ssp. enterica Typhimurium with intestinal cells under different iron concentrations encountered in the gut lumen during iron deficiency and supplementation using an in vitro colonic fermentation system inoculated with immobilized child gut microbiota combined with Caco-2/HT29-MTX co-culture monolayers. Colonic fermentation effluents obtained during normal, low (chelation by 2,2'-dipyridyl) and high iron (26.5 mg iron/L) fermentation conditions containing Salmonella or pure Salmonella cultures with similar iron conditions were applied to cellular monolayers. Salmonella adhesion and invasion capacity, cellular integrity and immune response were assessed. Under high iron conditions in pure culture, Salmonella adhesion was 8-fold increased compared to normal iron conditions while invasion was not affected leading to decreased invasion efficiency (-86%). Moreover, cellular cytokines IL-1β, IL-6, IL-8 and TNF-α secretion as well as NF-κB activation in THP-1 cells were attenuated under high iron conditions. Low iron conditions in pure culture increased Salmonella invasion correlating with an increase in IL-8 release. In fermentation effluents, Salmonella adhesion was 12-fold and invasion was 428-fold reduced compared to pure culture. Salmonella in high iron fermentation effluents had decreased invasion efficiency (-77.1%) and cellular TNF-α release compared to normal iron effluent. The presence of commensal microbiota and bacterial metabolites in fermentation effluents reduced adhesion and invasion of Salmonella compared to pure culture highlighting the importance of the gut microbiota as a barrier during pathogen invasion. High iron concentrations as

  15. Mammalian cadherins DCHS1-FAT4 affect functional cerebral architecture.

    PubMed

    Beste, Christian; Ocklenburg, Sebastian; von der Hagen, Maja; Di Donato, Nataliya

    2016-06-01

    Cortical development is a complex process where a multitude of factors, including cadherins, plays an important role and where disruptions are known to have far reaching effects in neural development and cortical patterning. Cadherins play a central role in structural left-right differentiation during brain and body development, but their effect on a functional level remains elusive. We addressed this question by examining functional cerebral asymmetries in a patient with Van Maldergem Syndrome (VMS) (MIM#601390), which is caused by mutations in DCHS1-FAT4 cadherins, using a dichotic listening task. Using neurophysiological (EEG) data, we show that when key regulators during mammalian cerebral cortical development are disrupted due to DCHS1-FAT4 mutations, functional cerebral asymmetries are stronger. Basic perceptual processing of biaurally presented auditory stimuli was unaffected. This suggests that the strength and emergence of functional cerebral asymmetries is a direct function of proliferation and differentiation of neuronal stem cells. Moreover, these results support the recent assumption that the molecular mechanisms establishing early left-right differentiation are an important factor in the ontogenesis of functional lateralization. PMID:25930014

  16. The inflammatory function of renal glomerular mesangial cells and their interaction with the cellular immune system.

    PubMed

    Radeke, H H; Resch, K

    1992-09-01

    The autoimmune nature of chronic progredient glomerular diseases has been well established. Like in other chronic inflammatory diseases, the active role of organ-borne cells has become increasingly apparent--both for the inflammatory process and for the initiation and perpetuation of the immune reaction. In most forms of glomerulonephritis, intrinsic glomerular mesangial cells are likely candidates to come into intimate contact with immune cells such as monocytes or lymphocytes. On the basis of cell culture studies we would like to integrate the current knowledge available about the responsiveness of mesangial cells to inflammatory agents and the resulting secretory capacity and, moreover, their possible role in sustaining chronic inflammatory injury and autoimmune reactions through a direct interaction with lymphocytes. Apart from being responsive to physiological stimuli such as angiotensin II, glomerular mesangial cells are predominantly activated by agents related to inflammation. This includes exogenous substances such as the components of gram-negative bacteria and an array of highly potent immunological stimuli like antigen-antibody complexes, activated complement, or various cytokines. The transformation of resting mesangial cells to proliferating cells with an accompanying expansion of their secretory profile and responsiveness is due to mediators like platelet-derived growth factor, transforming growth factor, and others. Numerous low-molecular-weight substances (O2-, H2O2, NO, platelet-activating factor, eicosanoids), proteins (proteinases, matrix components, interleukins 1 and 6, colony-stimulating factors, growth factors), and cell-surface molecules released or expressed by mesangial cells participate in the inflammatory process. Among these products interleukin 1 and/or 6, class II major histocompatibility antigen and integrins also support an interaction with the cellular immune system. It has been well documented that mesangial cells induced in

  17. Temperament Affects Sympathetic Nervous Function in a Normal Population

    PubMed Central

    Kim, Bora; Lee, Jae-Hon; Kang, Eun-Ho

    2012-01-01

    Objective Although specific temperaments have been known to be related to autonomic nervous function in some psychiatric disorders, there are few studies that have examined the relationship between temperaments and autonomic nervous function in a normal population. In this study, we examined the effect of temperament on the sympathetic nervous function in a normal population. Methods Sixty eight healthy subjects participated in the present study. Temperament was assessed using the Korean version of the Cloninger Temperament and Character Inventory (TCI). Autonomic nervous function was determined by measuring skin temperature in a resting state, which was recorded for 5 minutes from the palmar surface of the left 5th digit using a thermistor secured with a Velcro® band. Pearson's correlation analysis and multiple linear regression were used to examine the relationship between temperament and skin temperature. Results A higher harm avoidance score was correlated with a lower skin temperature (i.e. an increased sympathetic tone; r=-0.343, p=0.004) whereas a higher persistence score was correlated with a higher skin temperature (r=0.433, p=0.001). Hierarchical linear regression analysis revealed that harm avoidance was able to predict the variance of skin temperature independently, with a variance of 7.1% after controlling for sex, blood pressure and state anxiety and persistence was the factor predicting the variance of skin temperature with a variance of 5.0%. Conclusion These results suggest that high harm avoidance is related to an increased sympathetic nervous function whereas high persistence is related to decreased sympathetic nervous function in a normal population. PMID:22993530

  18. Fetal urinoma and prenatal hydronephrosis: how is renal function affected?

    PubMed Central

    Oktar, Tayfun; Salabaş, Emre; Kalelioğlu, İbrahim; Atar, Arda; Ander, Haluk; Ziylan, Orhan; Has, Recep; Yüksel, Atıl

    2013-01-01

    Objective: In our study, the functional prognosis of kidneys with prenatal urinomas were investigated. Material and methods: Between 2006 and 2010, fetal urinomas were detected in 19 fetuses using prenatal ultrasonography (US), and the medical records were reviewed retrospectively. Of the 19 cases, the follow-up data were available for 10 fetuses. The gestational age at diagnosis, prognosis of urinomas, clinical course and renal functions were recorded. Postnatal renal functions were assessed with renal scintigraphy. Results: Unilateral urinomas and increased parenchyma echogenicity in the ipsilateral kidney were detected in all of the fetuses. Of the 10 fetuses with follow-up data, the option of termination was offered in 6 cases of anhydramnios, including 3 cases with signs of infravesical obstruction (a possible posterior urethral valve (PUV) and poor prognostic factors and 3 cases with unilateral hydronephrosis and increased echogenicity in the contralateral kidney. Only one family agreed the termination. The other 5 fetuses died during the early postnatal period. The average postnatal follow-up period in the 4 surviving fetuses was 22.5 months (8–38 months). One patient with a PUV underwent ablation surgery during the early postnatal period. In the postnatal period, none of the 4 kidneys that were ipsilateral to the urinoma were functional on scintigraphic evaluation. The urinomas disappeared in 3 cases. Nephrectomy was performed in one case due to recurrent urinary tract infections. Conclusion: In our study, no function was detected in the ipsilateral kidney of surviving patients with urinomas. Upper urinary tract dilatation accompanied by a urinoma is a poor prognostic factor for renal function. PMID:26328088

  19. RNase-L control of cellular mRNAs: roles in biologic functions and mechanisms of substrate targeting.

    PubMed

    Brennan-Laun, Sarah E; Ezelle, Heather J; Li, Xiao-Ling; Hassel, Bret A

    2014-04-01

    RNase-L is a mediator of type 1 interferon-induced antiviral activity that has diverse and critical cellular roles, including the regulation of cell proliferation, differentiation, senescence and apoptosis, tumorigenesis, and the control of the innate immune response. Although RNase-L was originally shown to mediate the endonucleolytic cleavage of both viral and ribosomal RNAs in response to infection, more recent evidence indicates that RNase-L also functions in the regulation of cellular mRNAs as an important mechanism by which it exerts its diverse biological functions. Despite this growing body of work, many questions remain regarding the roles of mRNAs as RNase-L substrates. This review will survey known and putative mRNA substrates of RNase-L, propose mechanisms by which it may selectively cleave these transcripts, and postulate future clinical applications. PMID:24697205

  20. RNase-L Control of Cellular mRNAs: Roles in Biologic Functions and Mechanisms of Substrate Targeting

    PubMed Central

    Brennan-Laun, Sarah E.; Ezelle, Heather J.; Li, Xiao-Ling

    2014-01-01

    RNase-L is a mediator of type 1 interferon-induced antiviral activity that has diverse and critical cellular roles, including the regulation of cell proliferation, differentiation, senescence and apoptosis, tumorigenesis, and the control of the innate immune response. Although RNase-L was originally shown to mediate the endonucleolytic cleavage of both viral and ribosomal RNAs in response to infection, more recent evidence indicates that RNase-L also functions in the regulation of cellular mRNAs as an important mechanism by which it exerts its diverse biological functions. Despite this growing body of work, many questions remain regarding the roles of mRNAs as RNase-L substrates. This review will survey known and putative mRNA substrates of RNase-L, propose mechanisms by which it may selectively cleave these transcripts, and postulate future clinical applications. PMID:24697205

  1. Can Particulate Pollution Affect Lung Function in Healthy Adults?

    EPA Science Inventory

    Accompanying editorial to paper from Harvard by Rice et al. entitled "Long-Term Exposure to Traffic Emissions and Fine Particulate Matter and Lung Function Decline in the Framingham Heart StudyBy almost any measure the Clean Air Act and its amendments has to be considered as one...

  2. Drying process strongly affects probiotics viability and functionalities.

    PubMed

    Iaconelli, Cyril; Lemetais, Guillaume; Kechaou, Noura; Chain, Florian; Bermúdez-Humarán, Luis G; Langella, Philippe; Gervais, Patrick; Beney, Laurent

    2015-11-20

    Probiotic formulations are widely used and are proposed to have a variety of beneficial effects, depending on the probiotic strains present in the product. The impact of drying processes on the viability of probiotics is well documented. However, the impact of these processes on probiotics functionality remains unclear. In this work, we investigated variations in seven different bacterial markers after various desiccation processes. Markers were composed of four different viability evaluation (combining two growth abilities and two cytometric measurements) and in three in vitro functionalities: stimulation of IL-10 and IL-12 production by PBMCs (immunomodulation) and bacterial adhesion to hexadecane. We measured the impact of three drying processes (air-drying, freeze-drying and spray-drying), without the use of protective agents, on three types of probiotic bacteria: Bifidobacterium bifidum, Lactobacillus plantarum and Lactobacillus zeae. Our results show that the bacteria respond differently to the three different drying processes, in terms of viability and functionality. Drying methods produce important variations in bacterial immunomodulation and hydrophobicity, which are correlated. We also show that adherence can be stimulated (air-drying) or inhibited (spray-drying) by drying processes. Results of a multivariate analysis show no direct correlation between bacterial survival and functionality, but do show a correlation between probiotic responses to desiccation-rewetting and the process used to dry the bacteria. PMID:26325197

  3. Chemical Modifications that Affect Nutritional and Functional Properties of Proteins.

    ERIC Educational Resources Information Center

    Richardson, T.; Kester, J. J.

    1984-01-01

    Discusses chemical alterations of selected amino acids resulting from environmental effects (photooxidations, pH extremes, thermally induced effects). Also dicusses use of intentional chemical derivatizations of various functional groups in amino acid residue side chains and how recombinant DNA techniques might be useful in structure/function…

  4. Cellular resolution maps of X-chromosome inactivation: implications for neural development, function, and disease

    PubMed Central

    Wu, Hao; Luo, Junjie; Yu, Huimin; Rattner, Amir; Mo, Alisa; Wang, Yanshu; Smallwood, Philip M.; Erlanger, Bracha; Wheelan, Sarah J.; Nathans, Jeremy

    2014-01-01

    Female eutherian mammals use X-chromosome inactivation (XCI) to epigenetically regulate gene expression from ~4% of genes. To quantitatively map the topography of XCI for defined cell types at single cell resolution, we have generated female mice that carry X-linked, Cre-activated, and nuclear-localized fluorescent reporters – GFP on one X-chromosome and tdTomato on the other. Using these reporters in combination with different Cre drivers we have defined the topographies of XCI mosaicism for multiple CNS cell types and of retinal vascular dysfunction in a model of Norrie Disease. Depending on cell type, fluctuations in the XCI mosaic are observed over a wide range of spatial scales, from neighboring cells to left vs. right sides of the body. These data imply a major role for XCI in generating female-specific, genetically directed, stochastic diversity in eutherian mammals on spatial scales that would be predicted to affect CNS function within and between individuals. PMID:24411735

  5. Cellular resolution maps of X chromosome inactivation: implications for neural development, function, and disease.

    PubMed

    Wu, Hao; Luo, Junjie; Yu, Huimin; Rattner, Amir; Mo, Alisa; Wang, Yanshu; Smallwood, Philip M; Erlanger, Bracha; Wheelan, Sarah J; Nathans, Jeremy

    2014-01-01

    Female eutherian mammals use X chromosome inactivation (XCI) to epigenetically regulate gene expression from ∼4% of the genome. To quantitatively map the topography of XCI for defined cell types at single cell resolution, we have generated female mice that carry X-linked, Cre-activated, and nuclear-localized fluorescent reporters--GFP on one X chromosome and tdTomato on the other. Using these reporters in combination with different Cre drivers, we have defined the topographies of XCI mosaicism for multiple CNS cell types and of retinal vascular dysfunction in a model of Norrie disease. Depending on cell type, fluctuations in the XCI mosaic are observed over a wide range of spatial scales, from neighboring cells to left versus right sides of the body. These data imply a major role for XCI in generating female-specific, genetically directed, stochastic diversity in eutherian mammals on spatial scales that would be predicted to affect CNS function within and between individuals. PMID:24411735

  6. Gangliosides do not affect ABC transporter function in human neuroblastoma cells.

    PubMed

    Dijkhuis, Anne-Jan; Klappe, Karin; Kamps, Willem; Sietsma, Hannie; Kok, Jan Willem

    2006-06-01

    Previous studies have indicated a role for glucosylceramide synthase (GCS) in multidrug resistance (MDR), either related to turnover of ceramide (Cer) or generation of gangliosides, which modulate apoptosis and/or the activity of ABC transporters. This study challenges the hypothesis that gangliosides modulate the activity of ABC transporters and was performed in two human neuroblastoma cell lines, expressing either functional P-glycoprotein (Pgp) or multidrug resistance-related protein 1 (MRP1). Two inhibitors of GCS, D,L-threo-1-phenyl-2-hexadecanoylamino-3-pyrrolidino-1-propanol (t-PPPP) and N-butyldeoxynojirimycin (NB-dNJ), very efficiently depleted ganglioside content in two human neuroblastoma cell lines. This was established by three different assays: equilibrium radiolabeling, cholera toxin binding, and mass analysis. Fluorescence-activated cell sorting (FACS) analysis showed that ganglioside depletion only slightly and in the opposite direction affected Pgp- and MRP1-mediated efflux activity. Moreover, both effects were marginal compared with those of well-established inhibitors of either MRP1 (i.e., MK571) or Pgp (i.e., GF120918). t-PPPP slightly enhanced cellular sensitivity to vincristine, as determined by 3-[4,5-dimethylthiazol-2-yl]2,5-diphenyl tetrazolium bromide analysis, in both neuroblastoma cell lines, whereas NB-dNJ was without effect. MRP1 expression and its localization in detergent-resistant membranes were not affected by ganglioside depletion. Together, these results show that gangliosides are not relevant to ABC transporter-mediated MDR in neuroblastoma cells. PMID:16547352

  7. SLE-associated risk factors affect DC function

    PubMed Central

    Son, Myoungsun; Kim, Sun Jung; Diamond, Betty

    2016-01-01

    Numerous risk alleles for systemic lupus erythematosus (SLE) have now been identified. Analysis of the expression of genes with risk alleles in cells of hematopoietic origin demonstrates them to be most abundantly expressed in B cells and dendritic cells (DCs), suggesting that these cell types may be the drivers of the inflammatory changes seen in SLE. DCs are of particular interest as they act to connect the innate and the adaptive immune response. Thus, DCs can transform inflammation into autoimmunity, and autoantibodies are the hallmark of SLE. In this review, we focus on mechanisms of tolerance that maintain DCs in a non-activated, non-immunogenic state. We demonstrate, using examples from our own studies, how alterations in DC function stemming from either DC-intrinsic abnormalities or DC-extrinsic regulators of function can predispose to autoimmunity. PMID:26683148

  8. RIGHT HEMISPHERIC FUNCTION IN NORMALS, AFFECTIVE DISORDER AND SCHIZOPHRENIA

    PubMed Central

    Borde, Milind; Roy, Amal; Davis, Elizabeth J.B.; Davis, Rachel

    1996-01-01

    The happy-sad chimeric faces test has been established as a useful test of right hemispheric function. It is known to elicit a left hemifacial bias (LHF bias) in right handed subjects. 41 normals and 19 manic, depressive and schizophrenic patients each were tested. All subjects were strictly right handed. Normals and depressives showed significant LHF bias. Monies and schizophrenics did not show significant LHF Bias. This suggests right hemispheric dysfunction in both mania and schizophrenia. PMID:21584135

  9. Nuclear cyclophilins affect spliceosome assembly and function in vitro

    PubMed Central

    Adams, B.M.; Coates, Miranda N.; Jackson, S. RaElle; Jurica, Melissa S.; Davis, Tara L.

    2015-01-01

    Cyclophilins are ubiquitously expressed proteins that bind to prolines and can catalyse cis/trans isomerization of proline residues. There are 17 annotated members of the cyclophilin family in humans, ubiquitously expressed and localized variously to the cytoplasm, nucleus or mitochondria. Surprisingly, all eight of the nuclear localized cyclophilins are found associated with spliceosomal complexes. However, their particular functions within this context are unknown. We have therefore adapted three established assays for in vitro pre-mRNA splicing to probe the functional roles of nuclear cyclophilins in the context of the human spliceosome. We find that four of the eight spliceosom-associated cyclophilins exert strong effects on splicing in vitro. These effects are dose-dependent and, remarkably, uniquely characteristic of each cyclophilin. Using both qualitative and quantitative means, we show that at least half of the nuclear cyclophilins can act as regulatory factors of spliceosome function in vitro. The present work provides the first quantifiable evidence that nuclear cyclophilins are splicing factors and provides a novel approach for future work into small molecule-based modulation of pre-mRNA splicing. PMID:25967372

  10. Prenatal Drug Exposure Affects Neonatal Brain Functional Connectivity

    PubMed Central

    Salzwedel, Andrew P.; Vachet, Clement; Gerig, Guido; Lin, Weili

    2015-01-01

    Prenatal drug exposure, particularly prenatal cocaine exposure (PCE), incurs great public and scientific interest because of its associated neurodevelopmental consequences. However, the neural underpinnings of PCE remain essentially uncharted, and existing studies in school-aged children and adolescents are confounded greatly by postnatal environmental factors. In this study, leveraging a large neonate sample (N = 152) and non-invasive resting-state functional magnetic resonance imaging, we compared human infants with PCE comorbid with other drugs (such as nicotine, alcohol, marijuana, and antidepressant) with infants with similar non-cocaine poly drug exposure and drug-free controls. We aimed to characterize the neural correlates of PCE based on functional connectivity measurements of the amygdala and insula at the earliest stage of development. Our results revealed common drug exposure-related connectivity disruptions within the amygdala–frontal, insula–frontal, and insula–sensorimotor circuits. Moreover, a cocaine-specific effect was detected within a subregion of the amygdala–frontal network. This pathway is thought to play an important role in arousal regulation, which has been shown to be irregular in PCE infants and adolescents. These novel results provide the earliest human-based functional delineations of the neural-developmental consequences of prenatal drug exposure and thus open a new window for the advancement of effective strategies aimed at early risk identification and intervention. PMID:25855194

  11. Prenatal drug exposure affects neonatal brain functional connectivity.

    PubMed

    Salzwedel, Andrew P; Grewen, Karen M; Vachet, Clement; Gerig, Guido; Lin, Weili; Gao, Wei

    2015-04-01

    Prenatal drug exposure, particularly prenatal cocaine exposure (PCE), incurs great public and scientific interest because of its associated neurodevelopmental consequences. However, the neural underpinnings of PCE remain essentially uncharted, and existing studies in school-aged children and adolescents are confounded greatly by postnatal environmental factors. In this study, leveraging a large neonate sample (N = 152) and non-invasive resting-state functional magnetic resonance imaging, we compared human infants with PCE comorbid with other drugs (such as nicotine, alcohol, marijuana, and antidepressant) with infants with similar non-cocaine poly drug exposure and drug-free controls. We aimed to characterize the neural correlates of PCE based on functional connectivity measurements of the amygdala and insula at the earliest stage of development. Our results revealed common drug exposure-related connectivity disruptions within the amygdala-frontal, insula-frontal, and insula-sensorimotor circuits. Moreover, a cocaine-specific effect was detected within a subregion of the amygdala-frontal network. This pathway is thought to play an important role in arousal regulation, which has been shown to be irregular in PCE infants and adolescents. These novel results provide the earliest human-based functional delineations of the neural-developmental consequences of prenatal drug exposure and thus open a new window for the advancement of effective strategies aimed at early risk identification and intervention. PMID:25855194

  12. The effect of negative affect on cognition: Anxiety, not anger, impairs executive function.

    PubMed

    Shields, Grant S; Moons, Wesley G; Tewell, Carl A; Yonelinas, Andrew P

    2016-09-01

    It is often assumed that negative affect impairs the executive functions that underlie our ability to control and focus our thoughts. However, support for this claim has been mixed. Recent work has suggested that different negative affective states like anxiety and anger may reflect physiologically separable states with distinct effects on cognition. However, the effects of these 2 affective states on executive function have never been assessed. As such, we induced anxiety or anger in participants and examined the effects on executive function. We found that anger did not impair executive function relative to a neutral mood, whereas anxiety did. In addition, self-reports of induced anxiety, but not anger, predicted impairments in executive function. These results support functional models of affect and cognition, and highlight the need to consider differences between anxiety and anger when investigating the influence of negative affect on fundamental cognitive processes such as memory and executive function. (PsycINFO Database Record PMID:27100367

  13. Hydrogen peroxide sensors for cellular imaging based on horse radish peroxidase reconstituted on polymer-functionalized TiO₂ nanorods.

    PubMed

    Tahir, Muhammad Nawaz; André, Rute; Sahoo, Jugal Kishore; Jochum, Florian D; Theato, Patrick; Natalio, Filipe; Berger, Rüdiger; Branscheid, Robert; Kolb, Ute; Tremel, Wolfgang

    2011-09-01

    We describe the reconstitution of apo-horse radish peroxidase (apo-HRP) onto TiO(2) nanorods functionalized with a multifunctional polymer. After functionalization, the horse radish peroxidase (HRP) functionalized TiO(2) nanorods were well dispersible in aqueous solution, catalytically active and biocompatible, and they could be used to quantify and image H(2)O(2) which is a harmful secondary product of cellular metabolism. The shape, size and structure of TiO(2) nanorods (anatase) were analyzed by transmission electron microscopy (TEM), high resolution TEM (HRTEM), electron diffraction (ED) and X-ray diffraction (XRD). The surface functionalization, HRP reconstitution and catalytic activity were confirmed by UV-Vis, FT-IR, CLSM and atomic force microscopy (AFM). Biocompatibility and cellular internalization of active HRP reconstituted TiO(2) nanorods were confirmed by a classical MTT cytotoxicity assay and confocal laser scanning microscopy (CLSM) imaging, respectively. The intracellular localization allowed H(2)O(2) detection, imaging and quantification in HeLa cells. The polymer functionalized hybrid system creates a complete sensor including a "cell positioning system" in each single particle. The flexible synthetic concept with functionalization by post-polymerization modification allows introduction of various dyes for sensitisation at different wavelengths and introduction of various anchor groups for anchoring on different particles. PMID:21845257

  14. Mito-Morphosis: Mitochondrial Fusion, Fission, and Cristae Remodeling as Key Mediators of Cellular Function.

    PubMed

    Pernas, Lena; Scorrano, Luca

    2016-01-01

    Permanent residency in the eukaryotic cell pressured the prokaryotic mitochondrial ancestor to strategize for intracellular living. Mitochondria are able to autonomously integrate and respond to cellular cues and demands by remodeling their morphology. These processes define mitochondrial dynamics and inextricably link the fate of the mitochondrion and that of the host eukaryote, as exemplified by the human diseases that result from mutations in mitochondrial dynamics proteins. In this review, we delineate the architecture of mitochondria and define the mechanisms by which they modify their shape. Key players in these mechanisms are discussed, along with their role in manipulating mitochondrial morphology during cellular action and development. Throughout, we highlight the evolutionary context in which mitochondrial dynamics emerged and consider unanswered questions whose dissection might lead to mitochondrial morphology-based therapies. PMID:26667075

  15. Statin drugs mitigate cellular inflammatory response after ST elevation myocardial infarction, but do not affect in-hospital mortality

    PubMed Central

    Pourafkari, Leili; Visnjevac, Ognjen; Ghaffari, Samad; Nader, Nader D.

    2016-01-01

    Introduction: The objective was to examine the role of statins in modulating post-STEMI inflammation and related mortality. Methods: A total of 404 patients with STEMI were reviewed. Demographics, comorbidities, laboratory values, and outcomes were collected. The patients were grouped as STATIN and NOSTAT based on the use of statin drugs at the time of admission. Ninety-seven patients were receiving statin drugs. Results: The patients in the STATIN group were more likely to be hypertensive (53.6%), diabetic (37.1%) and to have previous coronary revascularization (9.3%). Following propensity matching of 89 patients in STATIN group to an equal number of patients in NOSTAT controls had lower neutrophil count 7.8 (6.8-8.4) compared to those in the NOSTAT group 9.1 (7.9-10.1). Although there was no difference in-hospital mortality between the two groups, the incidence of pump failure was lower in the STATIN group (5.6% vs. 15.7%; P < 0.01). Conclusion: Statin treatment prior to STEMI mitigates the cellular inflammatory response after the myocardial infarction, as evidenced by lower leukocyte and neutrophil cell counts in the STATIN group. PMID:27069565

  16. Effects of acamprosate on attentional set-shifting and cellular function in the prefrontal cortex of chronic alcohol-exposed mice

    NASA Astrophysics Data System (ADS)

    Hu, Wei

    Background: The medial prefrontal cortex (mPFC) inhibits impulsive and compulsive behaviors that characterize drug abuse and dependence. Acamprosate is the leading medication approved for the maintenance of abstinence, shown to reduce craving and relapse in animal models and human alcoholics. Whether acamprosate can modulate executive functions that are impaired by chronic ethanol exposure is unknown. Here we explored the effects of acamprosate on an attentional set-shifting task, and tested whether these behavioral effects are correlated with modulation of glutamatergic synaptic transmission and intrinsic excitability of mPFC neurons. Methods: We induced alcohol dependence in mice via chronic intermittent ethanol (CIE) exposure in vapor chambers and measured changes in alcohol consumption in a limited access 2-bottle choice paradigm. Impairments of executive function were assessed in an attentional set-shifting task. Acamprosate was applied subchronically for 2 days during withdrawal before the final behavioral test. Alcohol-induced changes in cellular function of layer 5/6 pyramidal neurons, and the potential modulation of these changes by acamprosate, were measured using patch clamp recordings in brain slices. Results: Chronic ethanol exposure impaired cognitive flexibility in the attentional set-shifting task. Acamprosate improved overall performance and reduced perseveration. Recordings of mPFC neurons showed that chronic ethanol exposure increased use-dependent presynaptic transmitter release and enhanced postsynaptic N-methyl-D-aspartate receptor (NMDAR) function. Moreover, CIE-treatment lowered input resistance, and decreased the threshold and the afterhyperpolarization (AHP) of action potentials, suggesting chronic ethanol exposure also impacted membrane excitability of mPFC neurons. However, acamprosate treatment did not reverse these ethanol-induced changes cellular function. Conclusion: Acamprosate improved attentional control of ethanol exposed animals

  17. Yersinia enterocolitica Affects Intestinal Barrier Function in the Colon.

    PubMed

    Hering, Nina A; Fromm, Anja; Kikhney, Judith; Lee, In-Fah M; Moter, Annette; Schulzke, Jörg D; Bücker, Roland

    2016-04-01

    Infection with Yersinia enterocolitica causes acute diarrhea in early childhood. A mouse infection model presents new findings on pathological mechanisms in the colon. Symptoms involve diarrhea with watery feces and weight loss that have their functional correlates in decreased transepithelial electrical resistance and increased fluorescein permeability. Y. enterocolitica was present within the murine mucosa of both ileum and colon. Here, the bacterial insult was of focal nature and led to changes in tight junction protein expression and architecture. These findings are in concordance with observations from former cell culture studies and suggest a leak flux mechanism of diarrhea. PMID:26621910

  18. Affected functional networks associated with sentence production in classic galactosemia.

    PubMed

    Timmers, Inge; van den Hurk, Job; Hofman, Paul Am; Zimmermann, Luc Ji; Uludağ, Kâmil; Jansma, Bernadette M; Rubio-Gozalbo, M Estela

    2015-08-01

    Patients with the inherited metabolic disorder classic galactosemia have language production impairments in several planning stages. Here, we assessed potential deviations in recruitment and connectivity across brain areas responsible for language production that may explain these deficits. We used functional magnetic resonance imaging (fMRI) to study neural activity and connectivity while participants carried out a language production task. This study included 13 adolescent patients and 13 age- and gender-matched healthy controls. Participants passively watched or actively described an animated visual scene using two conditions, varying in syntactic complexity (single words versus a sentence). Results showed that patients recruited additional and more extensive brain regions during sentence production. Both groups showed modulations with syntactic complexity in left inferior frontal gyrus (IFG), a region associated with syntactic planning, and in right insula. In addition, patients showed a modulation with syntax in left superior temporal gyrus (STG), whereas the controls did not. Further, patients showed increased activity in right STG and right supplementary motor area (SMA). The functional connectivity data showed similar patterns, with more extensive connectivity with frontal and motor regions, and restricted and weaker connectivity with superior temporal regions. Patients also showed higher baseline cerebral blood flow (CBF) in right IFG and trends towards higher CBF in bilateral STG, SMA and the insula. Taken together, the data demonstrate that language abnormalities in classic galactosemia are associated with specific changes within the language network. These changes point towards impairments related to both syntactic planning and speech motor planning in these patients. PMID:25979518

  19. Gene Risk Factors for Age-Related Brain Disorders May Affect Immune System Function

    MedlinePlus

    ... for age-related brain disorders may affect immune system function June 17, 2014 Scientists have discovered gene ... factors for age-related neurological disorders to immune system functions, such as inflammation, offers new insights into ...

  20. Confocal Light Absorption and Scattering Spectroscopic (CLASS) imaging: From cancer detection to sub-cellular function

    NASA Astrophysics Data System (ADS)

    Qiu, Le

    Light scattering spectroscopy (LSS), an optical technique that relates the spectroscopic properties of light elastically scattered by small particles to their size, refractive index and shape, has been recently successfully employed for sensing morphological and biochemical properties of epithelial tissues and cells in vivo. LSS does not require exogenous markers, is non-invasive, and, due to its multispectral nature, can sense biological structures well beyond the diffraction limit. All that makes LSS be a very good candidate to be used both in clinical medicine for in vivo detection of disease and in cell biology to monitor cell function on the organelle scale. Recently we developed two LSS-based imaging modalities: clinical Polarized LSS (PLSS) Endoscopic Technique for locating early pre-cancerous changes in GI tract and Confocal Light Absorption and Scattering Spectroscopic (CLASS) Microscopy for studying cells in vivo without exogenous markers. One important application of the clinical PLSS endoscopic instrument, a noncontact scanning imaging device compatible with the standard clinical endoscopes and capable of detecting dysplastic changes, is to serve as a guide for biopsy in Barrett's esophagus (BE). The instrument detects parallel and perpendicular components of the polarized light, backscattered from epithelial tissues, and determines characteristics of epithelial nuclei from the residual spectra. It also can find tissue oxygenation, hemoglobin content and other properties from the diffuse light component. By rapidly scanning esophagus the PLSS endoscopic instrument makes sure the entire BE portion is scanned and examined for the presence of dysplasia. CLASS microscopy, on the other hand, combines principles of light scattering spectroscopy (LSS) with confocal microscopy. Its main purpose is to image cells on organelle scale in vivo without the use of exogenous labels which may affect the cell function. The confocal geometry selects specific region and

  1. Does Vitamin C Deficiency Affect Cognitive Development and Function?

    PubMed Central

    Hansen, Stine Normann; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

    2014-01-01

    Vitamin C is a pivotal antioxidant in the brain and has been reported to have numerous functions, including reactive oxygen species scavenging, neuromodulation, and involvement in angiogenesis. Absence of vitamin C in the brain has been shown to be detrimental to survival in newborn SVCT2(−/−) mice and perinatal deficiency have shown to reduce hippocampal volume and neuron number and cause decreased spatial cognition in guinea pigs, suggesting that maternal vitamin C deficiency could have severe consequences for the offspring. Furthermore, vitamin C deficiency has been proposed to play a role in age-related cognitive decline and in stroke risk and severity. The present review discusses the available literature on effects of vitamin C deficiency on the developing and aging brain with particular focus on in vivo experimentation and clinical studies. PMID:25244370

  2. A Genomewide RNAi Screen for Genes That Affect the Stability, Distribution and Function of P Granules in Caenorhabditis elegans

    PubMed Central

    Updike, Dustin L.; Strome, Susan

    2009-01-01

    P granules are non-membrane-bound organelles found in the germ-line cytoplasm throughout Caenorhabditis elegans development. Like their “germ granule” counterparts in other animals, P granules are thought to act as determinants of the identity and special properties of germ cells, properties that include the unique ability to give rise to all tissues of future generations of an organism. Therefore, understanding how P granules work is critical to understanding how cellular immortality and totipotency are retained, gained, and lost. Here we report on a genomewide RNAi screen in C. elegans, which identified 173 genes that affect the stability, localization, and function of P granules. Many of these genes fall into specific classes with shared P-granule phenotypes, allowing us to better understand how cellular processes such as protein degradation, translation, splicing, nuclear transport, and mRNA homeostasis converge on P-granule assembly and function. One of the more striking phenotypes is caused by the depletion of CSR-1, an Argonaute associated with an endogenous siRNA pathway that functions in the germ line. We show that CSR-1 and two other endo-siRNA pathway members, the RNA-dependent RNA polymerase EGO-1 and the helicase DRH-3, act to antagonize RNA and P-granule accumulation in the germ line. Our findings strengthen the emerging view that germ granules are involved in numerous aspects of RNA metabolism, including an endo-siRNA pathway in germ cells. PMID:19805813

  3. Differential Effects of Polymer-Surface Decoration on Drug Delivery, Cellular Retention, and Action Mechanisms of Functionalized Mesoporous Silica Nanoparticles.

    PubMed

    You, Yuanyuan; Hu, Hao; He, Lizhen; Chen, Tianfeng

    2015-12-01

    Polymer-surface decoration has been found to be an effective strategy to enhance the biological activities of nanomedicine. Herein, three different types of polymers with a cancer-targeting ligand Arg-Gly-Asp peptide (RGD) have been used to decorate mesoporous silica nanoparticles (MSNs) and the functionalized nanosystems were used as drug carriers of oxaliplatin (OXA). The results showed that polymer-surface decoration of the MSNs nanosystem by poly(ethylene glycol) (PEG) and polyethyleneimine (PEI) significantly enhanced the anticancer efficacy of OXA, which was much higher than that of chitosan (CTS). This effect was closely related to the enhancement of the cellular uptake and cellular drug retention. Moreover, PEI@MSNs-OXA possessed excellent advantages in penetrating ability and inhibitory effects on SW480 spheroids that were used to simulate the in vivo tumor environments. Therefore, this study provides useful information for the rational design of a cancer-targeted MSNs nanosystem with polymer-surface decoration. PMID:26248202

  4. Elucidating the cellular uptake mechanism of aptamer-functionalized graphene-isolated-Au-nanocrystals with dual-modal imaging.

    PubMed

    Wang, Shanshan; Liu, Zhangkun; Zou, Yuxiu; Lai, Xiaofang; Ding, Ding; Chen, Long; Zhang, Liqin; Wu, Yuan; Chen, Zhuo; Tan, Weihong

    2016-05-23

    Elucidating the endocytosis and metabolism of nanoparticles in cells could improve the diagnostic sensitivity and therapeutic efficiency. In this work, we explore the cellular uptake mechanism of a biocompatible nanocrystal nanostructure, graphene-isolated-Au-nanocrystals (GIANs), by monitoring the intrinsic Raman and two-photon luminescence signals of GIANs in live cells. Aptamers functionalized on the GIAN nanostructure through simple, but strong, π-π interactions entered the cells through a clathrin-dependent pathway, while unmodified GIANs mainly entered the cells through a caveolae-mediated endocytosis pathway. Thus, it can be concluded that the mechanism of cellular uptake in these graphene-isolated-Au-nanocrystal nanostructures is determined by the presence or absence of aptamer modification. PMID:27111129

  5. Consumption of bee pollen affects rat ovarian functions.

    PubMed

    Kolesarova, A; Bakova, Z; Capcarova, M; Galik, B; Juracek, M; Simko, M; Toman, R; Sirotkin, A V

    2013-12-01

    The aim of this study was to examine possible effects of bee pollen added to the feed mixture (FM) on rat ovarian functions (secretion activity and apoptosis). We evaluated the bee pollen effect on the release of insulin-like growth factor I (IGF-I) and steroid hormones (progesterone and estradiol), as well as on the expression of markers of apoptosis (Bcl-2, Bax and caspase-3) in rat ovarian fragments. Female rats (n = 15) were fed during 90 days by FM without or with rape seed bee pollen in dose either 3 kg/1000 kg FM or 5 kg/1000 kg FM. Fragments of ovaries isolated from rats of each group (totally 72 pieces) were incubated for 24 h. Hormonal secretion into the culture medium was detected by RIA. The markers of apoptosis were evaluated by Western blotting. It was observed that IGF-I release by rat ovarian fragments was significantly (p < 0.05) decreased; on the other hand, progesterone and estradiol secretion was increased after bee pollen treatment at dose 5 kg/1000 kg FM but not at 3 kg/1000 FM. Accumulation of Bcl-2 was increased by bee pollen added at 3 kg/1000 kg FM, but not at higher dose. Accumulation of Bax was increased in ovaries of rats fed by bee pollen at doses either 3 or 5 kg/1000 kg FM, whilst accumulation of caspase-3 increased after feeding with bee pollen at dose 5 kg/1000 kg FM, but not at 3 kg/1000 kg FM. Our results contribute to new insights regarding the effect of bee pollen on both secretion activity (release of growth factor IGF-I and steroid hormones progesterone and estradiol) and apoptosis (anti- and pro-apoptotic markers Bcl-2, Bax and caspase-3). Bee pollen is shown to be a potent regulator of rat ovarian functions. PMID:23137268

  6. Neurology of Affective Prosody and Its Functional-Anatomic Organization in Right Hemisphere

    ERIC Educational Resources Information Center

    Ross, Elliott D.; Monnot, Marilee

    2008-01-01

    Unlike the aphasic syndromes, the organization of affective prosody in brain has remained controversial because affective-prosodic deficits may occur after left or right brain damage. However, different patterns of deficits are observed following left and right brain damage that suggest affective prosody is a dominant and lateralized function of…

  7. Functional TLR5 genetic variants affect human colorectal cancer survival.

    PubMed

    Klimosch, Sascha N; Försti, Asta; Eckert, Jana; Knezevic, Jelena; Bevier, Melanie; von Schönfels, Witigo; Heits, Nils; Walter, Jessica; Hinz, Sebastian; Lascorz, Jesus; Hampe, Jochen; Hartl, Dominik; Frick, Julia-Stefanie; Hemminki, Kari; Schafmayer, Clemens; Weber, Alexander N R

    2013-12-15

    Toll-like receptors (TLR) are overexpressed on many types of cancer cells, including colorectal cancer cells, but little is known about the functional relevance of these immune regulatory molecules in malignant settings. Here, we report frequent single-nucleotide polymorphisms (SNP) in the flagellin receptor TLR5 and the TLR downstream effector molecules MyD88 and TIRAP that are associated with altered survival in a large cohort of Caucasian patients with colorectal cancer (n = 613). MYD88 rs4988453, a SNP that maps to a promoter region shared with the acetyl coenzyme-A acyl-transferase-1 (ACAA1), was associated with decreased survival of patients with colorectal cancer and altered transcriptional activity of the proximal genes. In the TLR5 gene, rs5744174/F616L was associated with increased survival, whereas rs2072493/N592S was associated with decreased survival. Both rs2072493/N592S and rs5744174/F616L modulated TLR5 signaling in response to flagellin or to different commensal and pathogenic intestinal bacteria. Notably, we observed a reduction in flagellin-induced p38 phosphorylation, CD62L shedding, and elevated expression of interleukin (IL)-6 and IL-1β mRNA in human primary immune cells from TLR5 616LL homozygote carriers, as compared with 616FF carriers. This finding suggested that the well-documented effect of cytokines like IL-6 on colorectal cancer progression might be mediated by TLR5 genotype-dependent flagellin sensing. Our results establish an important link between TLR signaling and human colorectal cancer with relevance for biomarker and therapy development. PMID:24154872

  8. Familial Clustering of Executive Functioning in Affected Sibling Pair Families with ADHD

    ERIC Educational Resources Information Center

    Slaats-Willemse, Dorine; Swaab-Barneveld, Hanna; De Sonneville, Leo; Buitelaar, Jan

    2005-01-01

    Objective: To investigate familial clustering of executive functioning (i.e., response inhibition, fine visuomotor functioning, and attentional control) in attention-deficit/hyperactivity disorder (ADHD)-affected sibling pairs. Method: Fifty-two affected sibling pairs aged 6 to 18 years and diagnosed with ADHD according to DSM-IV performed the…

  9. Picornaviruses and nuclear functions: targeting a cellular compartment distinct from the replication site of a positive-strand RNA virus

    PubMed Central

    Flather, Dylan; Semler, Bert L.

    2015-01-01

    The compartmentalization of DNA replication and gene transcription in the nucleus and protein production in the cytoplasm is a defining feature of eukaryotic cells. The nucleus functions to maintain the integrity of the nuclear genome of the cell and to control gene expression based on intracellular and environmental signals received through the cytoplasm. The spatial separation of the major processes that lead to the expression of protein-coding genes establishes the necessity of a transport network to allow biomolecules to translocate between these two regions of the cell. The nucleocytoplasmic transport network is therefore essential for regulating normal cellular functioning. The Picornaviridae virus family is one of many viral families that disrupt the nucleocytoplasmic trafficking of cells to promote viral replication. Picornaviruses contain positive-sense, single-stranded RNA genomes and replicate in the cytoplasm of infected cells. As a result of the limited coding capacity of these viruses, cellular proteins are required by these intracellular parasites for both translation and genomic RNA replication. Being of messenger RNA polarity, a picornavirus genome can immediately be translated upon entering the cell cytoplasm. However, the replication of viral RNA requires the activity of RNA-binding proteins, many of which function in host gene expression, and are consequently localized to the nucleus. As a result, picornaviruses disrupt nucleocytoplasmic trafficking to exploit protein functions normally localized to a different cellular compartment from which they translate their genome to facilitate efficient replication. Furthermore, picornavirus proteins are also known to enter the nucleus of infected cells to limit host-cell transcription and down-regulate innate antiviral responses. The interactions of picornavirus proteins and host-cell nuclei are extensive, required for a productive infection, and are the focus of this review. PMID:26150805

  10. Phosphate Ions Affect the Water Structure at Functionalized Membrane Surfaces.

    PubMed

    Barrett, Aliyah; Imbrogno, Joseph; Belfort, Georges; Petersen, Poul B

    2016-09-01

    Antifouling surfaces improve function, efficiency, and safety in products such as water filtration membranes, marine vehicle coatings, and medical implants by resisting protein and biofilm adhesion. Understanding the role of water structure at these materials in preventing protein adhesion and biofilm formation is critical to designing more effective coatings. Such fouling experiments are typically performed under biological conditions using isotonic aqueous buffers. Previous studies have explored the structure of pure water at a few different antifouling surfaces, but the effect of electrolytes and ionic strength (I) on the water structure at antifouling surfaces is not well studied. Here sum frequency generation (SFG) spectroscopy is used to characterize the interfacial water structure at poly(ether sulfone) (PES) and two surface-modified PES films in contact with 0.01 M phosphate buffer with high and low salt (Ionic strength, I= 0.166 and 0.025 M, respectively). Unmodified PES, commonly used as a filtration membrane, and modified PES with a hydrophobic alkane (C18) and with a poly(ethylene glycol) (PEG) were used. In the low ionic strength phosphate buffer, water was strongly ordered near the surface of the PEG-modified PES film due to exclusion of phosphate ions and the creation of a surface potential resulting from charge separation between phosphate anions and sodium cations. However, in the high ionic strength phosphate buffer, the sodium and potassium chloride (138 and 3 mM, respectively) in the phosphate buffered saline screened this charge and substantially reduced water ordering. A much smaller water ordering and subsequent reduction upon salt addition was observed for the C18-modified PES, and little water structure change was seen for the unmodified PES. The large difference in water structuring with increasing ionic strength between widely used phosphate buffer and phosphate buffered saline at the PEG interface demonstrates the importance of studying

  11. Multi-functionality Redefined with Colloidal Carotene Carbon Nanoparticles for Synchronized Chemical Imaging, Enriched Cellular Uptake and Therapy.

    PubMed

    Misra, Santosh K; Mukherjee, Prabuddha; Chang, Huei-Huei; Tiwari, Saumya; Gryka, Mark; Bhargava, Rohit; Pan, Dipanjan

    2016-01-01

    Typically, multiplexing high nanoparticle uptake, imaging, and therapy requires careful integration of three different functions of a multiscale molecular-particle assembly. Here, we present a simpler approach to multiplexing by utilizing one component of the system for multiple functions. Specifically, we successfully synthesized and characterized colloidal carotene carbon nanoparticle (C(3)-NP), in which a single functional molecule served a threefold purpose. First, the presence of carotene moieties promoted the passage of the particle through the cell membrane and into the cells. Second, the ligand acted as a potent detrimental moiety for cancer cells and, finally, the ligands produced optical contrast for robust microscopic detection in complex cellular environments. In comparative tests, C(3)-NP were found to provide effective intracellular delivery that enables both robust detection at cellular and tissue level and presents significant therapeutic potential without altering the mechanism of intracellular action of β-carotene. Surface coating of C(3) with phospholipid was used to generate C(3)-Lipocoat nanoparticles with further improved function and biocompatibility, paving the path to eventual in vivo studies. PMID:27405011

  12. Multi-functionality Redefined with Colloidal Carotene Carbon Nanoparticles for Synchronized Chemical Imaging, Enriched Cellular Uptake and Therapy

    NASA Astrophysics Data System (ADS)

    Misra, Santosh K.; Mukherjee, Prabuddha; Chang, Huei-Huei; Tiwari, Saumya; Gryka, Mark; Bhargava, Rohit; Pan, Dipanjan

    2016-07-01

    Typically, multiplexing high nanoparticle uptake, imaging, and therapy requires careful integration of three different functions of a multiscale molecular-particle assembly. Here, we present a simpler approach to multiplexing by utilizing one component of the system for multiple functions. Specifically, we successfully synthesized and characterized colloidal carotene carbon nanoparticle (C3-NP), in which a single functional molecule served a threefold purpose. First, the presence of carotene moieties promoted the passage of the particle through the cell membrane and into the cells. Second, the ligand acted as a potent detrimental moiety for cancer cells and, finally, the ligands produced optical contrast for robust microscopic detection in complex cellular environments. In comparative tests, C3-NP were found to provide effective intracellular delivery that enables both robust detection at cellular and tissue level and presents significant therapeutic potential without altering the mechanism of intracellular action of β-carotene. Surface coating of C3 with phospholipid was used to generate C3-Lipocoat nanoparticles with further improved function and biocompatibility, paving the path to eventual in vivo studies.

  13. Multi-functionality Redefined with Colloidal Carotene Carbon Nanoparticles for Synchronized Chemical Imaging, Enriched Cellular Uptake and Therapy

    PubMed Central

    Misra, Santosh K.; Mukherjee, Prabuddha; Chang, Huei-Huei; Tiwari, Saumya; Gryka, Mark; Bhargava, Rohit; Pan, Dipanjan

    2016-01-01

    Typically, multiplexing high nanoparticle uptake, imaging, and therapy requires careful integration of three different functions of a multiscale molecular-particle assembly. Here, we present a simpler approach to multiplexing by utilizing one component of the system for multiple functions. Specifically, we successfully synthesized and characterized colloidal carotene carbon nanoparticle (C3-NP), in which a single functional molecule served a threefold purpose. First, the presence of carotene moieties promoted the passage of the particle through the cell membrane and into the cells. Second, the ligand acted as a potent detrimental moiety for cancer cells and, finally, the ligands produced optical contrast for robust microscopic detection in complex cellular environments. In comparative tests, C3-NP were found to provide effective intracellular delivery that enables both robust detection at cellular and tissue level and presents significant therapeutic potential without altering the mechanism of intracellular action of β-carotene. Surface coating of C3 with phospholipid was used to generate C3-Lipocoat nanoparticles with further improved function and biocompatibility, paving the path to eventual in vivo studies. PMID:27405011

  14. Cellular Signaling Networks Function as Generalized Wiener-Kolmogorov Filters to Suppress Noise

    NASA Astrophysics Data System (ADS)

    Hinczewski, Michael; Thirumalai, D.

    2014-10-01

    Cellular signaling involves the transmission of environmental information through cascades of stochastic biochemical reactions, inevitably introducing noise that compromises signal fidelity. Each stage of the cascade often takes the form of a kinase-phosphatase push-pull network, a basic unit of signaling pathways whose malfunction is linked with a host of cancers. We show that this ubiquitous enzymatic network motif effectively behaves as a Wiener-Kolmogorov optimal noise filter. Using concepts from umbral calculus, we generalize the linear Wiener-Kolmogorov theory, originally introduced in the context of communication and control engineering, to take nonlinear signal transduction and discrete molecule populations into account. This allows us to derive rigorous constraints for efficient noise reduction in this biochemical system. Our mathematical formalism yields bounds on filter performance in cases important to cellular function—such as ultrasensitive response to stimuli. We highlight features of the system relevant for optimizing filter efficiency, encoded in a single, measurable, dimensionless parameter. Our theory, which describes noise control in a large class of signal transduction networks, is also useful both for the design of synthetic biochemical signaling pathways and the manipulation of pathways through experimental probes such as oscillatory input.

  15. Dimer monomer transition and dimer re-formation play important role for ATM cellular function during DNA repair

    SciTech Connect

    Du, Fengxia; Zhang, Minjie; Li, Xiaohua; Yang, Caiyun; Meng, Hao; Wang, Dong; Chang, Shuang; Xu, Ye; Price, Brendan; Sun, Yingli

    2014-10-03

    Highlights: • ATM phosphorylates the opposite strand of the dimer in response to DNA damage. • The PETPVFRLT box of ATM plays a key role in its dimer dissociation in DNA repair. • The dephosphorylation of ATM is critical for dimer re-formation after DNA repair. - Abstract: The ATM protein kinase, is a serine/threonine protein kinase that is recruited and activated by DNA double-strand breaks, mediates responses to ionizing radiation in mammalian cells. Here we show that ATM is held inactive in unirradiated cells as a dimer and phosphorylates the opposite strand of the dimer in response to DNA damage. Cellular irradiation induces rapid intermolecular autophosphorylation of serine 1981 that causes dimer dissociation and initiates cellular ATM kinase activity. ATM cannot phosphorylate the substrates when it could not undergo dimer monomer transition. After DNA repair, the active monomer will undergo dephosphorylation to form dimer again and dephosphorylation is critical for dimer re-formation. Our work reveals novel function of ATM dimer monomer transition and explains why ATM dimer monomer transition plays such important role for ATM cellular activity during DNA repair.

  16. Functional cellular analyses reveal energy metabolism defect and mitochondrial DNA depletion in a case of mitochondrial aconitase deficiency.

    PubMed

    Sadat, Roa; Barca, Emanuele; Masand, Ruchi; Donti, Taraka R; Naini, Ali; De Vivo, Darryl C; DiMauro, Salvatore; Hanchard, Neil A; Graham, Brett H

    2016-05-01

    Defects in the tricarboxylic acid cycle (TCA) are associated with a spectrum of neurological phenotypes that are often difficult to diagnose and manage. Whole-exome sequencing (WES) led to a rapid expansion of diagnostic capabilities in such disorders and facilitated a better understanding of disease pathogenesis, although functional characterization remains a bottleneck to the interpretation of potential pathological variants. We report a 2-year-old boy of Afro-Caribbean ancestry, who presented with neuromuscular symptoms without significant abnormalities on routine diagnostic evaluation. WES revealed compound heterozygous missense variants of uncertain significance in mitochondrial aconitase (ACO2), which encodes the TCA enzyme ACO2. Pathogenic variants in ACO2 have been described in a handful of families as the cause of infantile cerebellar-retinal degeneration syndrome. Using biochemical and cellular assays in patient fibroblasts, we found that ACO2 expression was quantitatively normal, but ACO2 enzyme activity was <20% of that observed in control cells. We also observed a deficiency in cellular respiration and, for the first time, demonstrate evidence of mitochondrial DNA depletion and altered expression of some TCA components and electron transport chain subunits. The observed cellular defects were completely restored with ACO2 gene rescue. Our findings demonstrate the pathogenicity of two VUS in ACO2, provide novel mechanistic insights to TCA disturbances in ACO2 deficiency, and implicate mitochondrial DNA depletion in the pathogenesis of this recently described disorder. PMID:26992325

  17. Radiation-Induced Loss of Salivary Gland Function Is Driven by Cellular Senescence and Prevented by IL6 Modulation.

    PubMed

    Marmary, Yitzhak; Adar, Revital; Gaska, Svetlana; Wygoda, Annette; Maly, Alexander; Cohen, Jonathan; Eliashar, Ron; Mizrachi, Lina; Orfaig-Geva, Carmit; Baum, Bruce J; Rose-John, Stefan; Galun, Eithan; Axelrod, Jonathan H

    2016-03-01

    Head and neck cancer patients treated by radiation commonly suffer from a devastating side effect known as dry-mouth syndrome, which results from the irreversible loss of salivary gland function via mechanisms that are not completely understood. In this study, we used a mouse model of radiation-induced salivary hypofunction to investigate the outcomes of DNA damage in the head and neck region. We demonstrate that the loss of salivary function was closely accompanied by cellular senescence, as evidenced by a persistent DNA damage response (γH2AX and 53BP1) and the expression of senescence-associated markers (SA-βgal, p19ARF, and DcR2) and secretory phenotype (SASP) factors (PAI-1 and IL6). Notably, profound apoptosis or necrosis was not observed in irradiated regions. Signs of cellular senescence were also apparent in irradiated salivary glands surgically resected from human patients who underwent radiotherapy. Importantly, using IL6 knockout mice, we found that sustained expression of IL6 in the salivary gland long after initiation of radiation-induced DNA damage was required for both senescence and hypofunction. Additionally, we demonstrate that IL6 pretreatment prevented both senescence and salivary gland hypofunction via a mechanism involving enhanced DNA damage repair. Collectively, these results indicate that cellular senescence is a fundamental mechanism driving radiation-induced damage in the salivary gland and suggest that IL6 pretreatment may represent a promising therapeutic strategy to preserve salivary gland function in head and neck cancer patients undergoing radiotherapy. PMID:26759233

  18. Innervation of Gill Lateral Cells in the Bivalve Mollusc Crassostrea virginica Affects Cellular Membrane Potential and Cilia Activity

    PubMed Central

    Catapane, Edward J; Nelson, Michael; Adams, Trevon; Carroll, Margaret A

    2016-01-01

    Gill lateral cells of Crassostrea virginica are innervated by the branchial nerve, which contains serotonergic and dopaminergic fibers that regulate cilia beating rate. Terminal release of serotonin or dopamine results in an increase or decrease, respectively, of cilia beating rate in lateral gill cells. In this study we used the voltage sensitive fluorescent probe DiBAC4(3) to quantify changes in gill lateral cell membrane potential in response to electrical stimulation of the branchial nerve or to applications of serotonin and dopamine, and correlate these changes to cilia beating rates. Application of serotonin to gill lateral cells caused prolonged membrane depolarization, similar to plateau potentials, while increasing cilia beating rate. Application of dopamine hyperpolarized the resting membrane while decreasing cilia beating rate. Low frequency (5 Hz) electrical stimulations of the branchial nerve, which cause terminal release of endogenous serotonin, or high frequency (20 Hz) stimulations, which cause terminal release of endogenous dopamine, had the same effects on gill lateral cell membrane potentials and cilia beating rate as the respective applications of serotonin or dopamine. The study shows that innervation of gill lateral cells by the branchial nerve affects membrane potential as well as cilia beating rate, and demonstrates a strong correlation between changes in membrane potential and regulation of cilia beating rate. The study furthers the understanding of serotonin and dopamine signaling in the innervation and regulation of gill cilia in bivalves. The study also shows that voltage sensitive fluorescent probes like DiBAC 4(3) can be successfully used as an alternative to microelectrodes to measure changes in membrane potential of ciliated gill cells and other small cells with fast moving cilia. PMID:27489887

  19. Low-dose AgNPs reduce lung mechanical function and innate immune defense in the absence of cellular toxicity.

    PubMed

    Botelho, Danielle J; Leo, Bey Fen; Massa, Christopher B; Sarkar, Srijata; Tetley, Terry D; Chung, Kian Fan; Chen, Shu; Ryan, Mary P; Porter, Alexandra E; Zhang, Junfeng; Schwander, Stephan K; Gow, Andrew J

    2016-01-01

    Multiple studies have examined the direct cellular toxicity of silver nanoparticles (AgNPs). However, the lung is a complex biological system with multiple cell types and a lipid-rich surface fluid; therefore, organ level responses may not depend on direct cellular toxicity. We hypothesized that interaction with the lung lining is a critical determinant of organ level responses. Here, we have examined the effects of low dose intratracheal instillation of AgNPs (0.05 μg/g body weight) 20 and 110 nm diameter in size, and functionalized with citrate or polyvinylpyrrolidone. Both size and functionalization were significant factors in particle aggregation and lipid interaction in vitro. One day post-intratracheal instillation lung function was assessed, and bronchoalveolar lavage (BAL) and lung tissue collected. There were no signs of overt inflammation. There was no change in surfactant protein-B content in the BAL but there was loss of surfactant protein-D with polyvinylpyrrolidone (PVP)-stabilized particles. Mechanical impedance data demonstrated a significant increase in pulmonary elastance as compared to control, greatest with 110 nm PVP-stabilized particles. Seven days post-instillation of PVP-stabilized particles increased BAL cell counts, and reduced lung function was observed. These changes resolved by 21 days. Hence, AgNP-mediated alterations in the lung lining and mechanical function resolve by 21 days. Larger particles and PVP stabilization produce the largest disruptions. These studies demonstrate that low dose AgNPs elicit deficits in both mechanical and innate immune defense function, suggesting that organ level toxicity should be considered. PMID:26152688

  20. Adoptive transfer of natural antibodies to non-immunized chickens affects subsequent antigen-specific humoral and cellular immune responses.

    PubMed

    Lammers, Aart; Klomp, Marcel E V; Nieuwland, Mike G B; Savelkoul, Huub F J; Parmentier, Henk K

    2004-01-01

    To determine a regulatory function of natural antibodies in the immune response of chickens, pooled plasma obtained from non-immunized (naïve) 15 months old hens was subjected to keyhole limpet hemocyanin (KLH) antigen-affinity chromatography. Purified KLH-binding antibodies were adoptively transferred intravenously to 5 weeks-old cocks that were subsequently immunized subcutaneously 24 h later with KLH. Control groups consisted of birds that were either adoptively transferred with KLH-binding antibodies purified from plasma of KLH-immunized chickens, or PBS, or a salt precipitated total immunoglobulin fraction obtained from the corresponding pooled nai;ve chicken plasma, respectively.Total, IgM and IgY antibody titers to KLH in the plasma of recipients adoptively transferred with KLH-NAb, but not in the plasma of the groups transferred with salt precipitate or KLH-binding specific antibodies, were significantly enhanced as compared to the non-treated, KLH immunized group. Titers of IgA antibodies binding KLH were decreased in the plasma of the group that received specific KLH-binding antibodies, but not in the plasma of the other groups. Proliferation from peripheral blood leucocytes in whole blood from the KLH-NAb treated group, the group treated with KLH-binding specific antibodies and the group treated with salt precipitate, respectively, to both concanavalin A and KLH were significantly decreased as compared to the group receiving PBS. Our data show that antigen-specific antibodies can be isolated from plasma obtained from non-immunized chickens. Such antibodies that resemble natural antibodies as described in mammals may perform an important role in the enhancement of subsequent antigen-specific antibody responses or the maturation of the immune system, which may differ from the role of specific antibodies. PMID:12962982

  1. Cellular composition of periapical granulomas and its function. Histological, immunohistochemical and electronmicroscopic study.

    PubMed

    Babál, P; Brozman, M; Jakubovský, J; Basset, F; Jány, Z

    1989-01-01

    Periapical granulomas have been investigated histologically, immunohistologically using polyclonal and monoclonal antibodies, as well as electronmicroscopically. Lesions were formed by inflammatory granulation tissue frequently with foci of purulent exudation and fibrosis. Most numerous were plasma cells usually in cellular regions of the granulation tissue where they were tightly pressed. Of other cellular types were numerous lymphocytes, fibroblasts, less frequent were macrophages, scattered granulocytes and mast cells. More than a half of the plasma cells were IgG positive, about 20% IgA positive, up to 10% IgM, rarely IgE and sporadically IgD positive cells. In the vascular walls and their surrounding as well as in the phagocytes fine granular to granular positivities of C3 and C4 components of the complement were present. The majority of lymphocytes beared markers of T lymphocytes of which the T-suppressor markedly prevailed over the T-helper lymphocytes. In electron microscopy the plasma cells were most frequent. They were usually close to each other, sometimes with a disintegrated cytoplasmic membrane and non-damaged organelles being free around the nucleus. Mast cells were numerous and did not show any signs of marked degranulation. Rich production of immunoglobulins as well as the presence of IgG and IgM positive material in phagocytes, and the presence of positivities of the C3 and C4 components of the complement in the surrounding of the vessels and in phagocytes on the other hand supported the presumption that immune complexes participate in the pathogenesis of periapical granulomas. In spite of the presence of the IgE producing cells the morphological picture of mast cells did not suggest the presence of anaphylactic reaction in periapical lesions. Diffuse distribution of T lymphocytes, moreover with the prevalence of T-suppressor/cytotoxic over T-helper lymphocytes and not numerous macrophages in the inflammatory infiltrates did not suggest the

  2. Cellular Functions and X-ray Structure of Anthrolysin O, a Cholesterol-dependent Cytolysin Secreted by Bacillus anthracis*S⃞

    PubMed Central

    Bourdeau, Raymond W.; Malito, Enrico; Chenal, Alexandre; Bishop, Brian L.; Musch, Mark W.; Villereal, Mitch L.; Chang, Eugene B.; Mosser, Elise M.; Rest, Richard F.; Tang, Wei-Jen

    2009-01-01

    Anthrolysin O (ALO) is a pore-forming, cholesterol-dependent cytolysin (CDC) secreted by Bacillus anthracis, the etiologic agent for anthrax. Growing evidence suggests the involvement of ALO in anthrax pathogenesis. Here, we show that the apical application of ALO decreases the barrier function of human polarized epithelial cells as well as increases intracellular calcium and the internalization of the tight junction protein occludin. Using pharmacological agents, we also found that barrier function disruption requires increased intracellular calcium and protein degradation. We also report a crystal structure of the soluble state of ALO. Based on our analytical ultracentrifugation and light scattering studies, ALO exists as a monomer. Our ALO structure provides the molecular basis as to how ALO is locked in a monomeric state, in contrast to other CDCs that undergo antiparallel dimerization or higher order oligomerization in solution. ALO has four domains and is globally similar to perfringolysin O (PFO) and intermedilysin (ILY), yet the highly conserved undecapeptide region in domain 4 (D4) adopts a completely different conformation in all three CDCs. Consistent with the differences within D4 and at the D2-D4 interface, we found that ALO D4 plays a key role in affecting the barrier function of C2BBE cells, whereas PFO domain 4 cannot substitute for this role. Novel structural elements and unique cellular functions of ALO revealed by our studies provide new insight into the molecular basis for the diverse nature of the CDC family. PMID:19307185

  3. Inhibiting the NF-kappaB pathway to assess its function in the cellular response to space radiation

    NASA Astrophysics Data System (ADS)

    Koch, Kristina; Baumstark-Khan, Christa; Hellweg, Christine; Testard, Isabelle; Reitz, Guenther

    2012-07-01

    Radiation is regarded as one of the limiting factors for space missions. Therefore the cellular radiation response needs to be studied in order to estimate risks and to develop appropriate countermeasures. Exposure of human cells to ionizing radiation can provoke cell cycle arrest, leading to cellular senescence or premature differentiation, and different types of cell death. Previous heavy ion experiments have shown that the Nuclear Factor κB (NF-κB) pathway is activated by fluences that can be reached during long-term missions and thereby NF-κB was identified as an important modulating factor in the cellular radiation response. It could improve cellular survival after exposure to high radiation doses and influence the cancer risk of astronauts. The classical and the genotoxic stress induced NF-κB pathway result in nuclear translocation of the p65/p50 dimer. Both pathways might contribute to the cellular radiation response. Chemical inhibitors were tested to suppress the NF-κB pathway in recombinant HEK-pNF-κB-d2EGFP/Neo cells. The efficacy and cytotoxicity of the inhibitors targeting different elements of the NF-κB pathway were analyzed and found mostly inappropriate as inhibitors were partly cytotoxic or unspecific. Alternatively a functional knock-out of RelA (p65) was used to identify the contribution of the NF-κB pathway to different cellular outcomes. Small hairpin RNA constructs (shRNA) were transfected into the HEK-pNF-κB-d2EGFP/Neo cell line. Their functionality was assessed by quantitative Reverse Transcriptase real-time PCR (qRT-PCR) to verify that the RelA mRNA amount was reduced by more than 80% in the knock-down cells The original cell line had been stably transfected with a reporter system to monitor NF-κB activation by measuring destabilized Enhanced Green Fluorescent Protein (d2EGFP)-expression. It was shown that after 18 hours d2EGFP reaches its highest expression level after activation of NF-κB and can be measured by FACS analysis

  4. A knowledge base for the discovery of function, diagnostic potential and drug effects on cellular and extracellular miRNAs

    PubMed Central

    2014-01-01

    Background MicroRNAs (miRNAs) are small noncoding RNAs that play an important role in the regulation of various biological processes through their interaction with cellular mRNAs. A significant amount of miRNAs has been found in extracellular human body fluids (e.g. plasma and serum) and some circulating miRNAs in the blood have been successfully revealed as biomarkers for diseases including cardiovascular diseases and cancer. Released miRNAs do not necessarily reflect the abundance of miRNAs in the cell of origin. It is claimed that release of miRNAs from cells into blood and ductal fluids is selective and that the selection of released miRNAs may correlate with malignancy. Moreover, miRNAs play a significant role in pharmacogenomics by down-regulating genes that are important for drug function. In particular, the use of drugs should be taken into consideration while analyzing plasma miRNA levels as drug treatment. This may impair their employment as biomarkers. Description We enriched our manually curated extracellular/circulating microRNAs database, miRandola, by providing (i) a systematic comparison of expression profiles of cellular and extracellular miRNAs, (ii) a miRNA targets enrichment analysis procedure, (iii) information on drugs and their effect on miRNA expression, obtained by applying a natural language processing algorithm to abstracts obtained from PubMed. Conclusions This allows users to improve the knowledge about the function, diagnostic potential, and the drug effects on cellular and circulating miRNAs. PMID:25077952

  5. Characterization of molecular and cellular functions of the cyclin-dependent kinase CDK9 using a novel specific inhibitor

    PubMed Central

    Albert, T K; Rigault, C; Eickhoff, J; Baumgart, K; Antrecht, C; Klebl, B; Mittler, G; Meisterernst, M

    2014-01-01

    BACKGROUND AND PURPOSE The cyclin-dependent kinase CDK9 is an important therapeutic target but currently available inhibitors exhibit low specificity and/or narrow therapeutic windows. Here we have used a new highly specific CDK9 inhibitor, LDC000067 to interrogate gene control mechanisms mediated by CDK9. EXPERIMENTAL APPROACH The selectivity of LDC000067 was established in functional kinase assays. Functions of CDK9 in gene expression were assessed with in vitro transcription experiments, single gene analyses and genome-wide expression profiling. Cultures of mouse embryonic stem cells, HeLa cells, several cancer cell lines, along with cells from patients with acute myelogenous leukaemia were also used to investigate cellular responses to LDC000067. KEY RESULTS The selectivity of LDC000067 for CDK9 over other CDKs exceeded that of the known inhibitors flavopiridol and DRB. LDC000067 inhibited in vitro transcription in an ATP-competitive and dose-dependent manner. Gene expression profiling of cells treated with LDC000067 demonstrated a selective reduction of short-lived mRNAs, including important regulators of proliferation and apoptosis. Analysis of de novo RNA synthesis suggested a wide ranging positive role of CDK9. At the molecular and cellular level, LDC000067 reproduced effects characteristic of CDK9 inhibition such as enhanced pausing of RNA polymerase II on genes and, most importantly, induction of apoptosis in cancer cells. CONCLUSIONS AND IMPLICATIONS Our study provides a framework for the mechanistic understanding of cellular responses to CDK9 inhibition. LDC000067 represents a promising lead for the development of clinically useful, highly specific CDK9 inhibitors. PMID:24102143

  6. Cellular Defense and Sensory Cell Survival Require Distinct Functions of ebi in Drosophila

    PubMed Central

    Lim, Young-Mi; Yagi, Yoshimasa; Tsuda, Leo

    2015-01-01

    The innate immune response and stress-induced apoptosis are well-established signaling pathways related to cellular defense. NF-κB and AP-1 are redox-sensitive transcription factors that play important roles in those pathways. Here we show that Ebi, a Drosophila homolog of the mammalian co-repressor molecule transducin β-like 1 (TBL1), variously regulates the expression of specific genes that are targets of redox-sensitive transcription factors. In response to different stimuli, Ebi activated gene expression to support the acute immune response in fat bodies, whereas Ebi repressed genes that are involved in apoptosis in photoreceptor cells. Thus, Ebi seems to act as a regulatory switch for genes that are activated or repressed in response to different external stimuli. Our results offer clear in vivo evidence that the Ebi-containing co-repressor complex acts in a distinct manner to regulate transcription that is required for modulating the output of various processes during Drosophila development. PMID:26524764

  7. Molecular Biomechanics: The Molecular Basis of How Forces Regulate Cellular Function

    PubMed Central

    Bao, Gang; Kamm, Roger D.; Thomas, Wendy; Hwang, Wonmuk; Fletcher, Daniel A.; Grodzinsky, Alan J.; Zhu, Cheng; Mofrad, Mohammad R. K.

    2010-01-01

    Recent advances have led to the emergence of molecular biomechanics as an essential element of modern biology. These efforts focus on theoretical and experimental studies of the mechanics of proteins and nucleic acids, and the understanding of the molecular mechanisms of stress transmission, mechanosensing and mechanotransduction in living cells. In particular, single-molecule biomechanics studies of proteins and DNA, and mechanochemical coupling in biomolecular motors have demonstrated the critical importance of molecular mechanics as a new frontier in bioengineering and life sciences. To stimulate a more systematic study of the basic issues in molecular biomechanics, and attract a broader range of researchers to enter this emerging field, here we discuss its significance and relevance, describe the important issues to be addressed and the most critical questions to be answered, summarize both experimental and theoretical/computational challenges, and identify some short-term and long-term goals for the field. The needs to train young researchers in molecular biomechanics with a broader knowledge base, and to bridge and integrate molecular, subcellular and cellular level studies of biomechanics are articulated. PMID:20700472

  8. Flavoprotein imaging in the cerebellar cortex in vivo: cellular and metabolic basis and insights into cerebellar function

    NASA Astrophysics Data System (ADS)

    Gao, Wangcai; Chen, Gang; Ebner, Timothy J.

    2009-02-01

    Flavoprotein autofluorescence is an activity dependent intrinsic signal. Flavoproteins are involved in the electron transport chain and change their fluorescence according to the cellular redox state. We have been using flavoprotein autofluorescence in the cerebellum to examine properties of cerebellar circuits. Studies have also focused on understanding the cellular and metabolic origins of this intrinsic optical signal. Parallel fiber stimulation evokes a beamlike response intersected by bands of decreased fluorescence. The beam response is biphasic, with an early fluorescence increase (light phase) followed by a slower decrease (dark phase). We show this signal originates from flavoproteins as determined by its wavelength selectivity and sensitivity to blockers of the electron transport chain. Selectively blocking glutamate receptors abolished the on-beam light phase with the dark phase remaining intact. This demonstrates that the light phase is due to postsynaptic neuronal activation and suggests the dark phase is primarily due to glial activation. The bands of reduced fluorescence intersecting the beam are primarily neuronal in origin, mediated by GABAergic transmission, and due to the inhibitory action of molecular layer interneurons on Purkinje cells and the interneurons themselves. This parasagittally organized molecular layer inhibition differentially modulates the spatial pattern of cerebellar cortical activity. Flavoprotein imaging also reveals the functional architectures underlying the responses to inferior olive and peripheral whisker pad stimulation. Therefore, flavoprotein autofluorescence imaging is providing new insights into cerebellar cortical function and neurometabolic coupling.

  9. SIRT1-dependent regulation of chromatin and transcription: linking NAD(+) metabolism and signaling to the control of cellular functions.

    PubMed

    Zhang, Tong; Kraus, W Lee

    2010-08-01

    Sirtuins comprise a family of NAD(+)-dependent protein deacetylases and ADP-ribosyltransferases. Mammalian SIRT1 - a homolog of yeast Sir2, the prototypical member of the sirtuin family - is an important regulator of metabolism, cell differentiation and senescence, stress response, and cancer. As an NAD(+)-dependent enzyme, SIRT1 regulates gene expression programs in response to cellular metabolic status, thereby coordinating metabolic adaptation of the whole organism. Several important mechanisms have emerged for SIRT1-dependent regulation of transcription. First, SIRT1 can modulate chromatin function through direct deacetylation of histones as well as by promoting alterations in the methylation of histones and DNA, leading to the repression of transcription. The latter is accomplished through the recruitment of other nuclear enzymes to chromatin for histone methylation and DNA CpG methylation, suggesting a broader role of SIRT1 in epigenetic regulation. Second, SIRT1 can interact and deacetylate a broad range of transcription factors and coregulators, thereby regulating target gene expression both positively and negatively. Cellular energy state, specifically NAD(+) metabolism, plays a major role in the regulation of SIRT1 activity. Recent studies on the NAD(+) biosynthetic enzymes in the salvage pathway, nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide mononucleotide adenylyltransferase 1 (NMNAT-1), have revealed important functions for these enzymes in SIRT1-dependent transcription regulation. The collective molecular actions of SIRT1 control specific patterns of gene expression that modulate a wide variety of physiological outcomes. PMID:19879981

  10. The Na+/Glucose Cotransporter Inhibitor Canagliflozin Activates AMPK by Inhibiting Mitochondrial Function and Increasing Cellular AMP Levels.

    PubMed

    Hawley, Simon A; Ford, Rebecca J; Smith, Brennan K; Gowans, Graeme J; Mancini, Sarah J; Pitt, Ryan D; Day, Emily A; Salt, Ian P; Steinberg, Gregory R; Hardie, D Grahame

    2016-09-01

    Canagliflozin, dapagliflozin, and empagliflozin, all recently approved for treatment of type 2 diabetes, were derived from the natural product phlorizin. They reduce hyperglycemia by inhibiting glucose reuptake by sodium/glucose cotransporter (SGLT) 2 in the kidney, without affecting intestinal glucose uptake by SGLT1. We now report that canagliflozin also activates AMPK, an effect also seen with phloretin (the aglycone breakdown product of phlorizin), but not to any significant extent with dapagliflozin, empagliflozin, or phlorizin. AMPK activation occurred at canagliflozin concentrations measured in human plasma in clinical trials and was caused by inhibition of Complex I of the respiratory chain, leading to increases in cellular AMP or ADP. Although canagliflozin also inhibited cellular glucose uptake independently of SGLT2, this did not account for AMPK activation. Canagliflozin also inhibited lipid synthesis, an effect that was absent in AMPK knockout cells and that required phosphorylation of acetyl-CoA carboxylase (ACC) 1 and/or ACC2 at the AMPK sites. Oral administration of canagliflozin activated AMPK in mouse liver, although not in muscle, adipose tissue, or spleen. Because phosphorylation of ACC by AMPK is known to lower liver lipid content, these data suggest a potential additional benefit of canagliflozin therapy compared with other SGLT2 inhibitors. PMID:27381369

  11. Predicting the accuracy of facial affect recognition: the interaction of child maltreatment and intellectual functioning.

    PubMed

    Shenk, Chad E; Putnam, Frank W; Noll, Jennie G

    2013-02-01

    Previous research demonstrates that both child maltreatment and intellectual performance contribute uniquely to the accurate identification of facial affect by children and adolescents. The purpose of this study was to extend this research by examining whether child maltreatment affects the accuracy of facial recognition differently at varying levels of intellectual functioning. A sample of maltreated (n=50) and nonmaltreated (n=56) adolescent females, 14 to 19 years of age, was recruited to participate in this study. Participants completed demographic and study-related questionnaires and interviews to control for potential psychological and psychiatric confounds such as symptoms of posttraumatic stress disorder, negative affect, and difficulties in emotion regulation. Participants also completed an experimental paradigm that recorded responses to facial affect displays starting in a neutral expression and changing into a full expression of one of six emotions: happiness, sadness, anger, disgust, fear, or surprise. Hierarchical multiple regression assessed the incremental advantage of evaluating the interaction between child maltreatment and intellectual functioning. Results indicated that the interaction term accounted for a significant amount of additional variance in the accurate identification of facial affect after controlling for relevant covariates and main effects. Specifically, maltreated females with lower levels of intellectual functioning were least accurate in identifying facial affect displays, whereas those with higher levels of intellectual functioning performed as well as nonmaltreated females. These results suggest that maltreatment and intellectual functioning interact to predict the recognition of facial affect, with potential long-term consequences for the interpersonal functioning of maltreated females. PMID:23036371

  12. TRPV4 is necessary for trigeminal irritant pain and functions as a cellular formalin receptor

    PubMed Central

    Chen, Yong; Kanju, Patrick; Fang, Quan; Lee, Suk Hee; Parekh, Puja K.; Lee, Whasil; Moore, Carlene; Brenner, Daniel; Gereau, Robert W.; Wang, Fan; Liedtke, Wolfgang

    2014-01-01

    Detection of external irritants by head nociceptor neurons has deep evolutionary roots. Irritant-induced aversive behavior is a popular pain model in laboratory animals. It is used widely in the formalin-model, where formaldehyde is injected into the rodent paw, eliciting quantifiable nocifensive behavior that has a direct, tissue-injury-evoked phase, and a subsequent tonic phase caused by neural maladaptation. The formalin model has elucidated many anti-pain compounds and pain-modulating signaling pathways. We have adopted this model to trigeminally-innervated territories in mice. Also, we have examined the involvement of TRPV4 channels in formalin-evoked trigeminal pain behavior, because TRPV4 is abundantly expressed in trigeminal ganglion (TG) sensory neurons, also because we have recently defined TRPV4’s role in response to air-borne irritants, and in a model for temporomandibular joint pain. We found TRPV4 to be important for trigeminal nocifensive behavior evoked by formalin whiskerpad injections. This conclusion is supported by studies with Trpv4−/− mice and TRPV4-specific antagonists. Our results imply TRPV4 in MEK-ERK activation in TG sensory neurons. Furthermore, cellular studies in primary TG neurons and in heterologous TRPV4-expressing cells suggest that TRPV4 can be activated directly by formalin to gate Ca++. Using TRPA1-blocker and Trpa1−/− mice, we found that both TRP channels co-contribute to the formalin trigeminal pain response. These results imply TRPV4 as an important signaling molecule in irritation-evoked trigeminal pain. TRPV4-antagonistic therapies can therefore be envisioned as novel analgesics, possibly for specific targeting of trigeminal pain disorders, such as migraine, headaches, TMJ, facial and dental pain, and irritation of trigeminally-innervated surface epithelia. PMID:25281928

  13. Previously uncharacterized isoforms of divalent metal transporter (DMT)-1: implications for regulation and cellular function.

    PubMed

    Hubert, Nadia; Hentze, Matthias W

    2002-09-17

    Divalent metal transporter 1 (DMT1) mediates apical iron uptake into duodenal enterocytes and also transfers iron from the endosome into the cytosol after cellular uptake via the transferrin receptor. Hence, mutations in DMT1 cause systemic iron deficiency and anemia. DMT1 mRNA levels are increased in the duodenum of iron-deficient animals. This regulation has been observed for DMT1 mRNA harboring an iron-responsive element (IRE) in its 3' UTR, but not for a processing variant lacking a 3'UTR IRE, suggesting that the IRE regulates the expression of DMT1 mRNA in response to iron levels. Here, we show that iron regulation of DMT1 involves the expression of a previously unrecognized upstream 5' exon (exon 1A) of the human and murine DMT1 gene. The expression of this previously uncharacterized 5' exon is tissue-specific and particularly prevalent in the duodenum and kidney. It adds an in-frame AUG translation initiation codon extending the DMT1 ORF by a conserved sequence of 29-31 amino acids. In combination with the IRE- and non-IRE variants in the 3'UTR, our results reveal the existence of four DMT1 mRNA isoforms predicting the synthesis of four different DMT1 proteins. We show that two regulatory regions, the 5' promoter/exon 1A region and the IRE-containing terminal exon participate in iron regulation of DMT1 expression, which operate in a tissue-specific way. These results uncover an unexpected complexity of DMT1 expression and regulation, with implications for understanding the physiology, cell biology, and pathophysiology of mammalian iron metabolism. PMID:12209011

  14. Anacardic Acid, Salicylic Acid, and Oleic Acid Differentially Alter Cellular Bioenergetic Function in Breast Cancer Cells.

    PubMed

    Radde, Brandie N; Alizadeh-Rad, Negin; Price, Stephanie M; Schultz, David J; Klinge, Carolyn M

    2016-11-01

    Anacardic acid is a dietary and medicinal phytochemical that inhibits breast cancer cell proliferation and uncouples oxidative phosphorylation (OXPHOS) in isolated rat liver mitochondria. Since mitochondrial-targeted anticancer therapy (mitocans) may be useful in breast cancer, we examined the effect of anacardic acid on cellular bioenergetics and OXPHOS pathway proteins in breast cancer cells modeling progression to endocrine-independence: MCF-7 estrogen receptor α (ERα)+ endocrine-sensitive; LCC9 and LY2 ERα+, endocrine-resistant, and MDA-MB-231 triple negative breast cancer (TNBC) cells. At concentrations similar to cell proliferation IC50 s, anacardic acid reduced ATP-linked oxygen consumption rate (OCR), mitochondrial reserve capacity, and coupling efficiency while increasing proton leak, reflecting mitochondrial toxicity which was greater in MCF-7 compared to endocrine-resistant and TNBC cells. These results suggest tolerance in endocrine-resistant and TNBC cells to mitochondrial stress induced by anacardic acid. Since anacardic acid is an alkylated 2-hydroxybenzoic acid, the effects of salicylic acid (SA, 2-hydroxybenzoic acid moiety) and oleic acid (OA, monounsaturated alkyl moiety) were tested. SA inhibited whereas OA stimulated cell viability. In contrast to stimulation of basal OCR by anacardic acid (uncoupling effect), neither SA nor OA altered basal OCR- except OA inhibited basal and ATP-linked OCR, and increased ECAR, in MDA-MB-231 cells. Changes in OXPHOS proteins correlated with changes in OCR. Overall, neither the 2-hydroxybenzoic acid moiety nor the monounsaturated alky moiety of anacardic acid is solely responsible for the observed mitochondria-targeted anticancer activity in breast cancer cells and hence both moieties are required in the same molecule for the observed effects. J. Cell. Biochem. 117: 2521-2532, 2016. © 2016 Wiley Periodicals, Inc. PMID:26990649

  15. Utilization of microscale silicon cantilevers to assess cellular contractile function in vitro

    PubMed Central

    Smith, Alec S.T.; Long, Christopher J.; McAleer, Christopher; Bobbitt, Nathaniel; Srinivasan, Balaji; Hickman, James J.

    2016-01-01

    The development of more predictive and biologically relevant in vitro assays is predicated on the advancement of versatile cell culture systems which facilitate the functional assessment of the seeded cells. To that end, microscale cantilever technology offers a platform with which to measure the contractile functionality of a range of cell types, including skeletal, cardiac and smooth muscle cells, through assessment of contraction induced substrate bending. Application of multiplexed cantilever arrays provides the means to develop moderate to high-throughput protocols for assessing drug efficacy and toxicity, disease phenotype and progression, as well as neuromuscular and other cell-cell interactions. This manuscript provides the details for fabricating reliable cantilever arrays for this purpose, and the methods required to successfully culture cells on these surfaces. Further description is provided on the steps necessary to perform functional analysis of contractile cell types maintained on such arrays using a novel laser and photo-detector system. The representative data provided highlights the precision and reproducible nature of the analysis of contractile function possible using this system, as well as the wide range of studies to which such technology can be applied. Successful widespread adoption of this system could provide investigators with the means to perform rapid, low cost functional studies in vitro, leading to more accurate predictions of tissue performance, disease development and response to novel therapeutic treatment. PMID:25350792

  16. RNA in unexpected places: long non-coding RNA functions in diverse cellular contexts

    PubMed Central

    Geisler, Sarah; Coller, Jeff

    2016-01-01

    The increased application of transcriptome-wide profiling approaches has led to an explosion in the number of documented long non-coding RNAs (lncRNAs). While these new and enigmatic players in the complex transcriptional milieu are encoded by a significant proportion of the genome, their functions are mostly unknown. Early discoveries support a paradigm in which lncRNAs regulate transcription via chromatin modulation, but new functions are steadily emerging. Given the biochemical versatility of RNA, lncRNAs may be used for various tasks, including post-transcriptional regulation, organization of protein complexes, cell-cell signalling and allosteric regulation of proteins. PMID:24105322

  17. The emerging role of pseudogene expressed non-coding RNAs in cellular functions

    PubMed Central

    Groen, Jessica N.; Capraro, David; Morris, Kevin V.

    2014-01-01

    A paradigm shift is sweeping modern day molecular biology following the realisation that large amounts of “junk” DNA”, thought initially to be evolutionary remnants, may actually be functional. Several recent studies support a functional role for pseudogene-expressed non-coding RNAs in regulating their protein-coding counterparts. Several hundreds of pseudogenes have been reported as transcribed into RNA in a large variety of tissues and tumours. Most studies have focused on pseudogenes expressed in the sense direction, but some reports suggest that pseudogenes can also be transcribed as antisense RNAs (asRNAs). A few examples of key regulatory genes, such as PTEN and OCT4, have in fact been reported to be under the regulation of pseudogene-expressed asRNAs. Here, we review what are known about pseudogene expressed non-coding RNA mediated gene regulation and their roles in the control of epigenetic states. PMID:24842102

  18. Stress, ageing and their influence on functional, cellular and molecular aspects of the immune system.

    PubMed

    Vitlic, Ana; Lord, Janet M; Phillips, Anna C

    2014-06-01

    The immune response is essential for keeping an organism healthy and for defending it from different types of pathogens. It is a complex system that consists of a large number of components performing different functions. The adequate and controlled interaction between these components is necessary for a robust and strong immune response. There are, however, many factors that interfere with the way the immune response functions. Stress and ageing now consistently appear in the literature as factors that act upon the immune system in the way that is often damaging. This review focuses on the role of stress and ageing in altering the robustness of the immune response first separately, and then simultaneously, discussing the effects that emerge from their interplay. The special focus is on the psychological stress and the impact that it has at different levels, from the whole system to the individual molecules, resulting in consequences for physical health. PMID:24562499

  19. The N-terminal half of membrane CD14 is a functional cellular lipopolysaccharide receptor.

    PubMed Central

    Viriyakosol, S; Kirkland, T N

    1996-01-01

    CD14, a glycosylphosphatidylinositol-anchored protein on the surface of monocytes, macrophages, and polymorphonuclear leukocytes, is a receptor for lipopolysaccharide (LPS). It was recently reported that an N-terminal 152-amino-acid fragment of soluble CD14 was an active soluble lipopolysaccharide receptor (T. S. -C. Juan, M. J. Kelley, D. A. Johnson, L. A. Busse, E. Hailman, S. D. Wright, and H. S. Lichenstein, J. Biol. Chem. 270:1382-1387, 1995). To determine whether the N-terminal half of the membrane CD14 was a functional LPS receptor on the cell membrane, we engineered a chimeric gene coding for amino acids 1 to 151 of CD14 fused to the C-terminal region of decay-accelerating factor and expressed it in Chinese hamster ovary cells and 70Z/3 cells. We found that the chimeric, truncated CD14 is a fully functional LPS receptor in both cell lines. PMID:8550221

  20. Bioinspired genotype–phenotype linkages: mimicking cellular compartmentalization for the engineering of functional proteins

    PubMed Central

    van Vliet, Liisa D.; Colin, Pierre-Yves; Hollfelder, Florian

    2015-01-01

    The idea of compartmentalization of genotype and phenotype in cells is key for enabling Darwinian evolution. This contribution describes bioinspired systems that use in vitro compartments—water-in-oil droplets and gel-shell beads—for the directed evolution of functional proteins. Technologies based on these principles promise to provide easier access to protein-based therapeutics, reagents for processes involving enzyme catalysis, parts for synthetic biology and materials with biological components. PMID:26464791

  1. Cellular and molecular basis of chronic constipation: Taking the functional/idiopathic label out

    PubMed Central

    Bassotti, Gabrio; Villanacci, Vincenzo; Creƫoiu, Dragos; Creƫoiu, Sanda Maria; Becheanu, Gabriel

    2013-01-01

    In recent years, the improvement of technology and the increase in knowledge have shifted several strongly held paradigms. This is particularly true in gastroenterology, and specifically in the field of the so-called “functional” or “idiopathic” disease, where conditions thought for decades to be based mainly on alterations of visceral perception or aberrant psychosomatic mechanisms have, in fact, be reconducted to an organic basis (or, at the very least, have shown one or more demonstrable abnormalities). This is particularly true, for instance, for irritable bowel syndrome, the prototype entity of “functional” gastrointestinal disorders, where low-grade inflammation of both mucosa and myenteric plexus has been repeatedly demonstrated. Thus, researchers have also investigated other functional/idiopathic gastrointestinal disorders, and found that some organic ground is present, such as abnormal neurotransmission and myenteric plexitis in esophageal achalasia and mucosal immune activation and mild eosinophilia in functional dyspepsia. Here we show evidence, based on our own and other authors’ work, that chronic constipation has several abnormalities reconductable to alterations in the enteric nervous system, abnormalities mainly characterized by a constant decrease of enteric glial cells and interstitial cells of Cajal (and, sometimes, of enteric neurons). Thus, we feel that (at least some forms of) chronic constipation should no more be considered as a functional/idiopathic gastrointestinal disorder, but instead as a true enteric neuropathic abnormality. PMID:23864772

  2. Cellular uptake behavior of unfunctionalized and functionalized PBCA particles prepared in a miniemulsion.

    PubMed

    Weiss, Clemens K; Lorenz, Myriam R; Landfester, Katharina; Mailänder, Volker

    2007-07-01

    Fluorescent dye labeled unfunctionalized and functionalized poly(n-butylcyanoacrylate) nanoparticles were prepared using a miniemulsion technique. Amino acid and methoxyPEG functionalization could be introduced by using aqueous solutions as an initiator for the anionic polymerization in the heterophase. All the particles prepared had sizes smaller than 250 nm and negative zeta-potentials. The molar mass distribution of the polymer was dependent on the acid used as the continuous phase and the initiator solution applied. Cells of three lines (HeLa, Jurkat and mesenchymal stem cells) were incubated with the particles. The molar mass of the polymer determined the onset and extent of apoptosis, and the total uptake was determined by the size and functionalization of the particles. Different uptake kinetics were obtained with HeLa and Jurkat cells after incubation with the same particle batch. The intracellular particle distribution, visualized by confocal laser scanning microscopy, did not show significant differences for either of the cell lines or particle batches. PMID:17595680

  3. Tissue architecture and function: dynamic reciprocity via extra- and intra-cellular matrices

    PubMed Central

    Boudreau, Aaron

    2009-01-01

    Mammary gland development, functional differentiation, and homeostasis are orchestrated and sustained by a balance of biochemical and biophysical cues from the organ’s microenvironment. The three-dimensional microenvironment of the mammary gland, predominantly ‘encoded’ by a collaboration between the extracellular matrix (ECM), hormones, and growth factors, sends signals from ECM receptors through the cytoskeletal intracellular matrix to nuclear and chromatin structures resulting in gene expression; the ECM in turn is regulated and remodeled by signals from the nucleus. In this chapter, we discuss how coordinated ECM deposition and remodeling is necessary for mammary gland development, how the ECM provides structural and biochemical cues necessary for tissue-specific function, and the role of the cytoskeleton in mediating the extra—to intracellular dialogue occurring between the nucleus and the microenvironment. When operating normally, the cytoskeletal-mediated dynamic and reciprocal integration of tissue architecture and function directs mammary gland development, tissue polarity, and ultimately, tissue-specific gene expression. Cancer occurs when these dynamic inter-actions go awry for an extended time. PMID:19160017

  4. Tissue architecture and function: dynamic reciprocity via extra- and intra-cellular matrices

    SciTech Connect

    Xu, Ren; Boudreau, Aaron; Bissell, Mina J

    2008-12-23

    Mammary gland development, functional differentiation, and homeostasis are orchestrated and sustained by a balance of biochemical and biophysical cues from the organ's microenvironment. The three-dimensional microenvironment of the mammary gland, predominantly 'encoded' by a collaboration between the extracellular matrix (ECM), hormones, and growth factors, sends signals from ECM receptors through the cytoskeletal intracellular matrix to nuclear and chromatin structures resulting in gene expression; the ECM in turn is regulated and remodeled by signals from the nucleus. In this chapter, we discuss how coordinated ECM deposition and remodeling is necessary for mammary gland development, how the ECM provides structural and biochemical cues necessary for tissue-specific function, and the role of the cytoskeleton in mediating the extra - to intracellular dialogue occurring between the nucleus and the microenvironment. When operating normally, the cytoskeletal-mediated dynamic and reciprocal integration of tissue architecture and function directs mammary gland development, tissue polarity, and ultimately, tissue-specific gene expression. Cancer occurs when these dynamic interactions go awry for an extended time.

  5. Function and expression of a novel rat salt-tolerant protein: evidence of a role in cellular sodium metabolism.

    PubMed

    Tsuji, E; Tsuji, Y; Sasaguri, M; Arakawa, K

    1998-09-01

    Higher dietary salt intake in humans is associated with higher BP, but the BP response to NaCl, so-called salt sensitivity, is heterogeneous among individuals. It has been postulated that modifications in cellular cation metabolism may be related to salt sensitivity in mammalian hypertension. The authors have isolated a novel rat complementary DNA, called salt-tolerant protein (STP), that can functionally complement Saccharomyces cervisiae HAL1, which improves salt tolerance by modulating the cation transport system. On high-salt (8% NaCl) diets, both Dahl salt-sensitive and salt-resistant rats displayed an elevated BP and increased STP mRNA expression. Immunohistochemistry using an anti-rat STP antibody demonstrated the presence of STP immunoreactivity in the proximal tubules. In cells that transiently expressed STP, the intracellular [Na+]/[K+] ratio was higher than that in control cells. STP contains predicted coiled-coil and Src homology 3 domains, and shows a partially high degree of nucleotide identity to human thyroid-hormone receptor interacting protein. These results suggest that STP may play an important role in salt sensitivity through cellular sodium metabolism by mediating signal transduction and a hormone-dependent transcription mechanism. PMID:9727364

  6. The Influence of Metal Stress on the Availability and Redox State of Ascorbate, and Possible Interference with Its Cellular Functions

    PubMed Central

    Bielen, An; Remans, Tony; Vangronsveld, Jaco; Cuypers, Ann

    2013-01-01

    Worldwide, metals have been distributed to excessive levels in the environment due to industrial and agricultural activities. Plants growing on soils contaminated with excess levels of metals experience a disturbance of the cellular redox balance, which leads to an augmentation of reactive oxygen species (ROS). Even though the increased ROS levels can cause cellular damage, controlled levels play an important role in modulating signaling networks that control physiological processes and stress responses. Plants control ROS levels using their antioxidative defense system both under non-stress conditions, as well as under stress conditions such as exposure to excess metals. Ascorbate (AsA) is a well-known and important component of the plant’s antioxidative system. As primary antioxidant, it can reduce ROS directly and indirectly via ascorbate peroxidase in the ascorbate–glutathione cycle. Furthermore, AsA fulfills an essential role in physiological processes, some of which are disturbed by excess metals. In this review, known direct effects of excess metals on AsA biosynthesis and functioning will be discussed, as well as the possible interference of metals with the role of AsA in physiological and biochemical processes. PMID:23519107

  7. VolRoverN: Enhancing surface and volumetric reconstruction for realistic dynamical simulation of cellular and subcellular function

    PubMed Central

    Edwards, John; Daniel, Eric; Kinney, Justin; Bartol, Tom; Sejnowski, Terrence; Johnston, Daniel; Harris, Kristen; Bajaj, Chandrajit

    2014-01-01

    Establishing meaningful relationships between cellular structure and function requires accurate morphological reconstructions. In particular, there is an unmet need for high quality surface reconstructions to model subcellular and synaptic interactions among neurons at nanometer resolution. We address this need with VolRoverN, a software package that produces accurate, efficient, and automated 3D surface reconstructions from stacked 2D contour tracings. While many techniques and tools have been developed in the past for 3D visualization of cellular structure, the reconstructions from VolRoverN meet specific quality criteria that are important for dynamical simulations. These criteria include manifoldness, water-tightness, lack of self- and object-object-intersections, and geometric accuracy. These enhanced surface reconstructions are readily extensible to any cell type (including glia) and are used here on complex spiny dendrites and axons from mature rat hippocampal area CA1. Both spatially realistic surface reconstructions and reduced skeletonizations are produced and formatted by VolRoverN for easy input into analysis software packages for neurophysiological simulations at multiple spatial and temporal scales ranging from ion electro-diffusion to electrical cable models. PMID:24100964

  8. Snai2 and Snai3 transcriptionally regulate cellular fitness and functionality of T cell lineages through distinct gene programs.

    PubMed

    Pioli, Peter D; Whiteside, Sarah K; Weis, Janis J; Weis, John H

    2016-05-01

    T lymphocytes are essential contributors to the adaptive immune system and consist of multiple lineages that serve various effector and regulatory roles. As such, precise control of gene expression is essential to the proper development and function of these cells. Previously, we identified Snai2 and Snai3 as being essential regulators of immune tolerance partly due to the impaired function of CD4(+) regulatory T cells in Snai2/3 conditional double knockout mice. Here we extend those previous findings using a bone marrow transplantation model to provide an environmentally unbiased view of the molecular changes imparted onto various T lymphocyte populations once Snai2 and Snai3 are deleted. The data presented here demonstrate that Snai2 and Snai3 transcriptionally regulate the cellular fitness and functionality of not only CD4(+) regulatory T cells but effector CD8(α+) and CD4(+) conventional T cells as well. This is achieved through the modulation of gene sets unique to each cell type and includes transcriptional targets relevant to the survival and function of each T cell lineage. As such, Snai2 and Snai3 are essential regulators of T cell immunobiology. PMID:26831822

  9. Positive Affect in the Midst of Distress: Implications for Role Functioning

    PubMed Central

    Moskowitz, Judith Tedlie; Shmueli-Blumberg, Dikla; Acree, Michael; Folkman, Susan

    2012-01-01

    Stress has been shown to deplete the self-regulation resources hypothesized to facilitate effective role functioning. However, recent research suggests that positive affect may help to replenish these vital self-regulation resources. Based on revised Stress and Coping theory and the Broaden-and-Build theory of positive emotion, three studies provide evidence of the potential adaptive function of positive affect in the performance of roles for participants experiencing stress. Participants were students (Study 1), caregivers of ill children (Study 2), and individuals recently diagnosed with HIV (Study 3). In cross sectional analyses, using role functioning as an indicator of self-regulation performance, we found that positive affect was significantly correlated with better self regulation performance, independent of the effects of negative affect. The effects were not as strong longitudinally, however, and there was little evidence of a reciprocal association between increases in positive affect and improvements in role functioning over time. The results provide some modest support for hypotheses stemming from the Broaden and Build model of positive emotion and revised Stress and Coping theory, both of which argue for unique adaptive functions of positive affect under stressful conditions. PMID:23175617

  10. c-Myc and AMPK Control Cellular Energy Levels by Cooperatively Regulating Mitochondrial Structure and Function

    PubMed Central

    Edmunds, Lia R.; Sharma, Lokendra; Wang, Huabo; Kang, Audry; d’Souza, Sonia; Lu, Jie; McLaughlin, Michael; Dolezal, James M.; Gao, Xiaoli; Weintraub, Susan T.; Ding, Ying; Zeng, Xuemei; Yates, Nathan; Prochownik, Edward V.

    2015-01-01

    The c-Myc (Myc) oncoprotein and AMP-activated protein kinase (AMPK) regulate glycolysis and oxidative phosphorylation (Oxphos) although often for different purposes. Because Myc over-expression depletes ATP with the resultant activation of AMPK, we explored the potential co-dependency of and cross-talk between these proteins by comparing the consequences of acute Myc induction in ampk+/+ (WT) and ampk-/- (KO) murine embryo fibroblasts (MEFs). KO MEFs showed a higher basal rate of glycolysis than WT MEFs and an appropriate increase in response to activation of a Myc-estrogen receptor (MycER) fusion protein. However, KO MEFs had a diminished ability to increase Oxphos, mitochondrial mass and reactive oxygen species in response to MycER activation. Other differences between WT and KO MEFs, either in the basal state or following MycER induction, included abnormalities in electron transport chain function, levels of TCA cycle-related oxidoreductases and cytoplasmic and mitochondrial redox states. Transcriptional profiling of pathways pertinent to glycolysis, Oxphos and mitochondrial structure and function also uncovered significant differences between WT and KO MEFs and their response to MycER activation. Finally, an unbiased mass-spectrometry (MS)-based survey capable of quantifying ~40% of all mitochondrial proteins, showed about 15% of them to be AMPK- and/or Myc-dependent in their steady state. Significant differences in the activities of the rate-limiting enzymes pyruvate kinase and pyruvate dehydrogenase, which dictate pyruvate and acetyl coenzyme A abundance, were also differentially responsive to Myc and AMPK and could account for some of the differences in basal metabolite levels that were also detected by MS. Thus, Myc and AMPK are highly co-dependent and appear to engage in significant cross-talk across numerous pathways which support metabolic and ATP-generating functions. PMID:26230505

  11. Functional expression and cellular distribution of diastrophic dysplasia sulfate transporter (DTDST) gene mutations in HEK cells.

    PubMed

    Karniski, Lawrence P

    2004-10-01

    Defects in sulfate transport in chondrocytes lead to undersulfation of the cartilage extracellular matrix proteoglycans. Mutations in the diastrophic dysplasia sulfate transporter (DTDST) gene have been linked to four chondrodysplasias of varying severity. To characterize disease-causing mutations of DTDST, we expressed DTDST-mediated sulfate transport in mammalian HEK-293 cells and determined that the wild-type protein is glycosylated and localized to the cell plasma membrane. Four mutations, A715V, C653S, Q454P and R279W, stimulated sulfate transport at rates only 39-62% of wild-type DTDST. These four mutations were expressed on the plasma membrane of the cell, but the amount of expressed protein was reduced when compared with wild-type DTDST. The Q454P mutant is unique in that it is not properly glycosylated in HEK cells. There was no difference in sulfate transport activity between cells transfected with either the DeltaV340 or the G678V mutations and control HEK cells. Furthermore, the G678V mutation is not expressed along the plasma membrane, but is trapped within the cytoplasm. When comparing the sulfate transport capacity of each DTDST mutation with the chondrodysplasia in which it has been identified, we find that individuals with severe achondrogenesis 1B phenotype have null mutations on both DTDST alleles. Heterozygotes for both a null mutation and a partial-function mutation result in either atelosteogenesis type 2 or DTD, whereas the milder, recessive multiple epiphyseal dysplasia phenotype is homozygous for partial-function mutations. In contrast to previous studies in Xenopus laevis oocytes, we find a strong correlation between the severity of the phenotype and the level of residual transport function in mammalian cells. PMID:15294877

  12. Expression and cellular function of vSNARE proteins in brain astrocytes.

    PubMed

    Ropert, N; Jalil, A; Li, D

    2016-05-26

    Gray matter protoplasmic astrocytes, a major type of glial cell in the mammalian brain, extend thin processes ensheathing neuronal synaptic terminals. Albeit electrically silent, astrocytes respond to neuronal activity with Ca(2+) signals that trigger the release of gliotransmitters, such as glutamate, d-serine, and ATP, which modulate synaptic transmission. It has been suggested that the astrocytic processes, together with neuronal pre- and post-synaptic elements, constitute a tripartite synapse, and that astrocytes actively regulate information processing. Astrocytic vesicles expressing VAMP2 and VAMP3 vesicular SNARE (vSNARE) proteins have been suggested to be a key feature of the tripartite synapse and mediate gliotransmitter release through Ca(2+)-regulated exocytosis. However, the concept of exocytotic release of gliotransmitters by astrocytes has been challenged. Here we review studies investigating the expression profile of VAMP2 and VAMP3 vSNARE proteins in rodent astrocytes, and the functional implication of VAMP2/VAMP3 vesicles in astrocyte signaling. We also discuss our recent data suggesting that astrocytic VAMP3 vesicles regulate the trafficking of glutamate transporters at the plasma membrane and glutamate uptake. A better understanding of the functional consequences of the astrocytic vSNARE vesicles on glutamate signaling, neuronal excitability and plasticity, will require the development of new strategies to selectively interrogate the astrocytic vesicles trafficking in vivo. PMID:26518463

  13. Evolution and cellular function of monothiol glutaredoxins: involvement in iron-sulphur cluster assembly.

    PubMed

    Vilella, Felipe; Alves, Rui; Rodríguez-Manzaneque, María Teresa; Bellí, Gemma; Swaminathan, Swarna; Sunnerhagen, Per; Herrero, Enrique

    2004-01-01

    A number of bacterial species, mostly proteobacteria, possess monothiol glutaredoxins homologous to the Saccharomyces cerevisiae mitochondrial protein Grx5, which is involved in iron-sulphur cluster synthesis. Phylogenetic profiling is used to predict that bacterial monothiol glutaredoxins also participate in the iron-sulphur cluster (ISC) assembly machinery, because their phylogenetic profiles are similar to the profiles of the bacterial homologues of yeast ISC proteins. High evolutionary co-occurrence is observed between the Grx5 homologues and the homologues of the Yah1 ferredoxin, the scaffold proteins Isa1 and Isa2, the frataxin protein Yfh1 and the Nfu1 protein. This suggests that a specific functional interaction exists between these ISC machinery proteins. Physical interaction analyses using low-definition protein docking predict the formation of strong and specific complexes between Grx5 and several components of the yeast ISC machinery. Two-hybrid analysis has confirmed the in vivo interaction between Grx5 and Isa1. Sequence comparison techniques and cladistics indicate that the other two monothiol glutaredoxins of S. cerevisiae, Grx3 and Grx4, have evolved from the fusion of a thioredoxin gene with a monothiol glutaredoxin gene early in the eukaryotic lineage, leading to differential functional specialization. While bacteria do not contain these chimaeric glutaredoxins, in many eukaryotic species Grx5 and Grx3/4-type monothiol glutaredoxins coexist in the cell. PMID:18629168

  14. Silk sericin-alginate-chitosan microcapsules: hepatocytes encapsulation for enhanced cellular functions.

    PubMed

    Nayak, Sunita; Dey, Sanchareeka; Kundu, Subhas C

    2014-04-01

    The encapsulation based technology permits long-term delivery of desired therapeutic products in local regions of body without the need of immunosuppressant drugs. In this study microcapsules composed of sericin and alginate micro bead as inner core and with an outer chitosan shell are prepared. This work is proposed for live cell encapsulation for potential therapeutic applications. The sericin protein is obtained from cocoons of non-mulberry silkworm Antheraea mylitta. The sericin-alginate micro beads are prepared via ionotropic gelation under high applied voltage. The beads further coated with chitosan and crosslinked with genipin. The microcapsules developed are nearly spherical in shape with smooth surface morphology. Alamar blue assay and confocal microscopy indicate high cell viability and uniform encapsulated cell distribution within the sericin-alginate-chitosan microcapsules indicating that the microcapsules maintain favourable microenvironment for the cells. The functional analysis of encapsulated cells demonstrates that the glucose consumption, urea secretion rate and intracellular albumin content increased in the microcapsules. The study suggests that the developed sericin-alginate-chitosan microcapsule contributes towards the development of cell encapsulation model. It also offers to generate enriched population of metabolically and functionally active cells for the future therapeutics especially for hepatocytes transplantation in acute liver failure. PMID:24486492

  15. Next-generation biomedical implants using additive manufacturing of complex, cellular and functional mesh arrays.

    PubMed

    Murr, L E; Gaytan, S M; Medina, F; Lopez, H; Martinez, E; Machado, B I; Hernandez, D H; Martinez, L; Lopez, M I; Wicker, R B; Bracke, J

    2010-04-28

    In this paper, we examine prospects for the manufacture of patient-specific biomedical implants replacing hard tissues (bone), particularly knee and hip stems and large bone (femoral) intramedullary rods, using additive manufacturing (AM) by electron beam melting (EBM). Of particular interest is the fabrication of complex functional (biocompatible) mesh arrays. Mesh elements or unit cells can be divided into different regions in order to use different cell designs in different areas of the component to produce various or continually varying (functionally graded) mesh densities. Numerous design elements have been used to fabricate prototypes by AM using EBM of Ti-6Al-4V powders, where the densities have been compared with the elastic (Young) moduli determined by resonant frequency and damping analysis. Density optimization at the bone-implant interface can allow for bone ingrowth and cementless implant components. Computerized tomography (CT) scans of metal (aluminium alloy) foam have also allowed for the building of Ti-6Al-4V foams by embedding the digital-layered scans in computer-aided design or software models for EBM. Variations in mesh complexity and especially strut (or truss) dimensions alter the cooling and solidification rate, which alters the alpha-phase (hexagonal close-packed) microstructure by creating mixtures of alpha/alpha' (martensite) observed by optical and electron metallography. Microindentation hardness measurements are characteristic of these microstructures and microstructure mixtures (alpha/alpha') and sizes. PMID:20308113

  16. Regulation of cellular function via electromagnetic field frequency and extracellular environment: A theoretical- experimental approach

    NASA Astrophysics Data System (ADS)

    Taghian, Toloo; Sheikh, Abdul; Narmoneva, Daria; Kogan, Andrei

    2015-03-01

    Application of external electric field (EF) as a non-pharmacological, non-invasive tool to control cell function is of great therapeutic interest. We developed a theoretical-experimental approach to investigate the biophysical mechanisms of EF interaction with cells in electrode-free physiologically-relevant configuration. Our numerical results demonstrated that EF frequency is the major parameter to control cell response to EF. Non-oscillating or low-frequency EF leads to charge accumulation on the cell surface membrane that may mediate membrane initiated cell responses. In contrast, high-frequency EF penetrates the cell membrane and reaches cell cytoplasm, where it may directly activate intracellular responses. The theoretical predictions were confirmed in our experimental studies of the effects of applied EF on vascular cell function. Results show that non-oscillating EF increases vascular endothelial growth factor (VEGF) expression while field polarity controls cell adhesion rate. High-frequency, but not low frequency, EF provides differential regulation of cytoplasmic focal adhesion kinase and VEGF expression depending on the substrate, with increased expression in cells cultured on RGD-rich synthetic hydrogels, and decreased expression for matrigel culture. The authors acknowledge the financial support from the NSF (DMR-1206784 & DMR-0804199 to AK); the NIH (1R21 DK078814-01A1 to DN) and the University of Cincinnati (Interdisciplinary Faculty Research Support Grant to DN and AK).

  17. NMDA-R inhibition affects cellular process formation in Tilapia melanocytes; a model for pigmented adrenergic neurons in process formation and retraction.

    PubMed

    Ogundele, Olalekan Michael; Okunnuga, Adetokunbo Adedotun; Fabiyi, Temitope Deborah; Olajide, Olayemi Joseph; Akinrinade, Ibukun Dorcas; Adeniyi, Philip Adeyemi; Ojo, Abiodun Ayodele

    2014-06-01

    elongation of secondary cellular processes (highly branched) from primary major processes (Less branched); co-incubation of glutamate and ketamine induced short and highly branched process formation. Cyanide toxicity induced degeneration and reduction of cell size while co-treatment of cyanide and ketamine gave changes similar to that observed in glutamate-ketamine co-incubation. NMDA-R is present in the melanocytes. Activation of the receptor reduced elongation process, while inhibition of the receptor facilitated cell process elongation and branching. This confirms that like pigmented adrenergic cells of the nervous system, this cell contains NMDA-R and this receptor also regulates cell process elongation. The study also showed that inhibition of NMDA-R in melanocytes gave opposite outcomes to the role of the receptor in developing neurons; a function that is protective in adult neurons. PMID:24242214

  18. Alteration of some cellular function in amikacin resistant Pseudomonas aeruginosa transfected macrophages: a time dependent approach

    PubMed Central

    Chakraborty, Subhankari Prasad; KarMahapatra, Santanu; Das, Sabyasachi; Roy, Somenath

    2011-01-01

    Objective To evaluate the free radical generation and antioxidant enzymes status in murine peritoneal macrophage during in vitro amikacin resistant Pseudomonas aeruginosa (ARPA) treatment with different time interval. Methods Peritoneal macrophages were treated with 1×108 CFU/mL ARPA cell suspension in vitro for different time interval (1, 2, 3, 6, 12, and 24 h) and super oxide anion generation, NO generation, reduced glutathione level and antioxidant enzymes status were analyzed. Results Super oxide anion generation and NO generation got peak at 12 h, indicating maximal free radical generation through activation of NADPH oxidase in murine peritoneal macrophages during ARPA transfection. Reduced glutathione level and antioxidant enzymes status were decreased significantly (P<0.05) with increasing time of ARPA transfection. All the changes in peritoneal macrophages after 12 h in vitro ARPA transfection had significant difference (P<0.05). Conclusions From this study, it may be summarized that in vitro ARPA infection not only generates excess free radical but also affects the antioxidant system and glutathione cycle in murine peritoneal macrophage. PMID:23569818

  19. Viral Interference with Functions of the Cellular Receptor Tyrosine Phosphatase CD45

    PubMed Central

    Thiel, Nadine; Zischke, Jasmin; Elbasani, Endrit; Kay-Fedorov, Penelope; Messerle, Martin

    2015-01-01

    The receptor tyrosine phosphatase CD45 is expressed on the surface of almost all cells of hematopoietic origin. CD45 functions are central to the development of T cells and determine the threshold at which T and B lymphocytes can become activated. Given this pivotal role of CD45 in the immune system, it is probably not surprising that viruses interfere with the activity of CD45 in lymphocytes to dampen the immune response and that they also utilize this molecule to accomplish their replication cycle. Here we report what is known about the interaction of viral proteins with CD45. Moreover, we debate putative interactions of viruses with CD45 in myeloid cells and the resulting consequences—subjects that remain to be investigated. Finally, we summarize the evidence that pathogens were the driving force for the evolution of CD45. PMID:25807057

  20. 3D Conducting Polymer Platforms for Electrical Control of Protein Conformation and Cellular Functions

    PubMed Central

    Wan, Alwin Ming-Doug; Inal, Sahika; Williams, Tiffany; Wang, Karin; Leleux, Pierre; Estevez, Luis; Giannelis, Emmanuel P.; Fischbach, Claudia; Malliaras, George G.; Gourdon, Delphine

    2015-01-01

    We report the fabrication of three dimensional (3D) macroporous scaffolds made from poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) via an ice-templating method. The scaffolds offer tunable pore size and morphology, and are electrochemically active. When a potential is applied to the scaffolds, reversible changes take place in their electrical doping state, which in turn enables precise control over the conformation of adsorbed proteins (e.g., fibronectin). Additionally, the scaffolds support the growth of mouse fibroblasts (3T3-L1) for 7 days, and are able to electrically control cell adhesion and pro-angiogenic capability. These 3D matrix-mimicking platforms offer precise control of protein conformation and major cell functions, over large volumes and long cell culture times. As such, they represent a new tool for biological research with many potential applications in bioelectronics, tissue engineering, and regenerative medicine. PMID:26413300

  1. Role of Mitochondria in Cerebral Vascular Function: Energy Production, Cellular Protection, and Regulation of Vascular Tone.

    PubMed

    Busija, David W; Rutkai, Ibolya; Dutta, Somhrita; Katakam, Prasad V

    2016-01-01

    Mitochondria not only produce energy in the form of ATP to support the activities of cells comprising the neurovascular unit, but mitochondrial events, such as depolarization and/or ROS release, also initiate signaling events which protect the endothelium and neurons against lethal stresses via pre-/postconditioning as well as promote changes in cerebral vascular tone. Mitochondrial depolarization in vascular smooth muscle (VSM), via pharmacological activation of the ATP-dependent potassium channels on the inner mitochondrial membrane (mitoKATP channels), leads to vasorelaxation through generation of calcium sparks by the sarcoplasmic reticulum and subsequent downstream signaling mechanisms. Increased release of ROS by mitochondria has similar effects. Relaxation of VSM can also be indirectly achieved via actions of nitric oxide (NO) and other vasoactive agents produced by endothelium, perivascular and parenchymal nerves, and astroglia following mitochondrial activation. Additionally, NO production following mitochondrial activation is involved in neuronal preconditioning. Cerebral arteries from female rats have greater mitochondrial mass and respiration and enhanced cerebral arterial dilation to mitochondrial activators. Preexisting chronic conditions such as insulin resistance and/or diabetes impair mitoKATP channel relaxation of cerebral arteries and preconditioning. Surprisingly, mitoKATP channel function after transient ischemia appears to be retained in the endothelium of large cerebral arteries despite generalized cerebral vascular dysfunction. Thus, mitochondrial mechanisms may represent the elusive signaling link between metabolic rate and blood flow as well as mediators of vascular change according to physiological status. Mitochondrial mechanisms are an important, but underutilized target for improving vascular function and decreasing brain injury in stroke patients. © 2016 American Physiological Society. Compr Physiol 6:1529-1548, 2016. PMID:27347901

  2. Physicochemical properties and cellular toxicity of (poly)aminoalkoxysilanes-functionalized ZnO quantum dots

    NASA Astrophysics Data System (ADS)

    Aboulaich, Abdelhay; Tilmaciu, Carmen-Mihaela; Merlin, Christophe; Mercier, Cédric; Guilloteau, Hélène; Medjahdi, Ghouti; Schneider, Raphaël

    2012-08-01

    Luminescent ZnO nanocrystals were synthesized by basic hydrolysis of Zn(OAc)2 in the presence of oleic acid and then functionalized with (poly)aminotrimethoxysilanes in the presence of tetramethylammonium hydroxide to render the QDs water-dispersible. The highest photoluminescence quantum yield (17%) was achieved using N1-(2-aminoethyl)-N2-[3-(trimethoxysilyl)propyl]-1,2-ethanediamine as surface ligand. Transmission electron microscopy and powder x-ray diffraction showed highly crystalline materials with a ZnO nanoparticle diameter of about 4 nm. The cytotoxicity of the different siloxane-capped ZnO QDs towards growing Escherichia coli bacterial cells was evaluated in MOPS-minimal medium. Although concentrations of 5 mM in QDs caused a complete growth arrest in E. coli, siloxane-capped ZnO QDs appeared weakly toxic at lower doses (0.5 or 1 mM). The concentration of bioavailable Zn 2+ ions leaked from ZnO QDs was evaluated using the biosensor bacteria Cupriavidus metallidurans AE1433. The results obtained clearly demonstrate that concentrations of bioavailable Zn2+ are too low to explain the inhibitory effects of the ZnO QDs against bacteria cells at 1 mM and that the siloxane shell prevents ZnO QDs from dissolution contrary to uncapped ZnO nanoparticles. Because of their low cytotoxicity, good biocompatibility, low cost and large number of functional amine end groups, which makes them easy to tailor for end-user purposes, siloxane-capped ZnO QDs offer a high potential as fluorescent probes and as biosensors.

  3. Physicochemical properties and cellular toxicity of (poly)aminoalkoxysilanes-functionalized ZnO quantum dots.

    PubMed

    Aboulaich, Abdelhay; Tilmaciu, Carmen-Mihaela; Merlin, Christophe; Mercier, Cédric; Guilloteau, Hélène; Medjahdi, Ghouti; Schneider, Raphaël

    2012-08-24

    Luminescent ZnO nanocrystals were synthesized by basic hydrolysis of Zn(OAc)(2) in the presence of oleic acid and then functionalized with (poly)aminotrimethoxysilanes in the presence of tetramethylammonium hydroxide to render the QDs water-dispersible. The highest photoluminescence quantum yield (17%) was achieved using N(1)-(2-aminoethyl)-N(2)-[3-(trimethoxysilyl)propyl]-1,2-ethanediamine as surface ligand. Transmission electron microscopy and powder x-ray diffraction showed highly crystalline materials with a ZnO nanoparticle diameter of about 4 nm. The cytotoxicity of the different siloxane-capped ZnO QDs towards growing Escherichia coli bacterial cells was evaluated in MOPS-minimal medium. Although concentrations of 5 mM in QDs caused a complete growth arrest in E. coli, siloxane-capped ZnO QDs appeared weakly toxic at lower doses (0.5 or 1 mM). The concentration of bioavailable Zn (2+) ions leaked from ZnO QDs was evaluated using the biosensor bacteria Cupriavidus metallidurans AE1433. The results obtained clearly demonstrate that concentrations of bioavailable Zn(2+) are too low to explain the inhibitory effects of the ZnO QDs against bacteria cells at 1 mM and that the siloxane shell prevents ZnO QDs from dissolution contrary to uncapped ZnO nanoparticles. Because of their low cytotoxicity, good biocompatibility, low cost and large number of functional amine end groups, which makes them easy to tailor for end-user purposes, siloxane-capped ZnO QDs offer a high potential as fluorescent probes and as biosensors. PMID:22865601

  4. Cyclic Di-GMP Regulates Multiple Cellular Functions in the Symbiotic Alphaproteobacterium Sinorhizobium meliloti

    PubMed Central

    Schäper, Simon; Krol, Elizaveta; Skotnicka, Dorota; Kaever, Volkhard; Hilker, Rolf; Søgaard-Andersen, Lotte

    2015-01-01

    ABSTRACT Sinorhizobium meliloti undergoes major lifestyle changes between planktonic states, biofilm formation, and symbiosis with leguminous plant hosts. In many bacteria, the second messenger 3′,5′-cyclic di-GMP (c-di-GMP, or cdG) promotes a sessile lifestyle by regulating a plethora of processes involved in biofilm formation, including motility and biosynthesis of exopolysaccharides (EPS). Here, we systematically investigated the role of cdG in S. meliloti Rm2011 encoding 22 proteins putatively associated with cdG synthesis, degradation, or binding. Single mutations in 21 of these genes did not cause evident changes in biofilm formation, motility, or EPS biosynthesis. In contrast, manipulation of cdG levels by overproducing endogenous or heterologous diguanylate cyclases (DGCs) or phosphodiesterases (PDEs) affected these processes and accumulation of N-Acyl-homoserine lactones in the culture supernatant. Specifically, individual overexpression of the S. meliloti genes pleD, SMb20523, SMb20447, SMc01464, and SMc03178 encoding putative DGCs and of SMb21517 encoding a single-domain PDE protein had an impact and resulted in increased levels of cdG. Compared to the wild type, an S. meliloti strain that did not produce detectable levels of cdG (cdG0) was more sensitive to acid stress. However, it was symbiotically potent, unaffected in motility, and only slightly reduced in biofilm formation. The SMc01790-SMc01796 locus, homologous to the Agrobacterium tumefaciens uppABCDEF cluster governing biosynthesis of a unipolarly localized polysaccharide, was found to be required for cdG-stimulated biofilm formation, while the single-domain PilZ protein McrA was identified as a cdG receptor protein involved in regulation of motility. IMPORTANCE We present the first systematic genome-wide investigation of the role of 3′,5′-cyclic di-GMP (c-di-GMP, or cdG) in regulation of motility, biosynthesis of exopolysaccharides, biofilm formation, quorum sensing, and symbiosis in a

  5. A Phylogenomic Census of Molecular Functions Identifies Modern Thermophilic Archaea as the Most Ancient Form of Cellular Life

    PubMed Central

    Kim, Kyung Mo; Caetano-Anollés, Gustavo

    2014-01-01

    The origins of diversified life remain mysterious despite considerable efforts devoted to untangling the roots of the universal tree of life. Here we reconstructed phylogenies that described the evolution of molecular functions and the evolution of species directly from a genomic census of gene ontology (GO) definitions. We sampled 249 free-living genomes spanning organisms in the three superkingdoms of life, Archaea, Bacteria, and Eukarya, and used the abundance of GO terms as molecular characters to produce rooted phylogenetic trees. Results revealed an early thermophilic origin of Archaea that was followed by genome reduction events in microbial superkingdoms. Eukaryal genomes displayed extraordinary functional diversity and were enriched with hundreds of novel molecular activities not detected in the akaryotic microbial cells. Remarkably, the majority of these novel functions appeared quite late in evolution, synchronized with the diversification of the eukaryal superkingdom. The distribution of GO terms in superkingdoms confirms that Archaea appears to be the simplest and most ancient form of cellular life, while Eukarya is the most diverse and recent. PMID:25249790

  6. Effect of Surface Functionalization on the Cellular Uptake and Toxicity of Nanozeolite A.

    PubMed

    Męczyńska-Wielgosz, Sylwia; Piotrowska, Agata; Majkowska-Pilip, Agnieszka; Bilewicz, Aleksander; Kruszewski, Marcin

    2016-12-01

    Extensive use of zeolite nanoparticles in many areas, including medicine, has led to the concern about an impact and possible risk of their use for human health and the environment.In our studies, we investigated an uptake, retention, and cytotoxicity of nanozeolite A (BaA) functionalized with aminopropyl or poly(ethylene glycol) (PEG) of different chain lengths using human cervical carcinoma cell line. For internalization studies, nanozeolite was labeled with (133)Ba radionuclide.The results show that in the case of PEG modification, toxicity and uptake depend on the PEG chain length. The highest toxicity has been observed for nanozeolites coated with short-length chain (Ba-silane-PEGm(MW350). Also, amine-modified nanozeolites exhibited high toxicity, while nanozeolites coated with long PEG molecules, BaA-silane-PEGm(MW1000), and BaA-silane-PEGm(MW2000), as well as unmodified nanozeolite, seem to be nontoxic.In conclusion, this study shows that uptake, retention, and toxicity of nanozeolites coated with various length PEG molecules groups depend on the molecular weight of PEG. PMID:26935303

  7. Functional genomics and proteomics of the cellular osmotic stress response in 'non-model' organisms.

    PubMed

    Kültz, Dietmar; Fiol, Diego; Valkova, Nelly; Gomez-Jimenez, Silvia; Chan, Stephanie Y; Lee, Jinoo

    2007-05-01

    All organisms are adapted to well-defined extracellular salinity ranges. Osmoregulatory mechanisms spanning all levels of biological organization, from molecules to behavior, are central to salinity adaptation. Functional genomics and proteomics approaches represent powerful tools for gaining insight into the molecular basis of salinity adaptation and euryhalinity in animals. In this review, we discuss our experience in applying such tools to so-called 'non-model' species, including euryhaline animals that are well-suited for studies of salinity adaptation. Suppression subtractive hybridization, RACE-PCR and mass spectrometry-driven proteomics can be used to identify genes and proteins involved in salinity adaptation or other environmental stress responses in tilapia, sharks and sponges. For protein identification in non-model species, algorithms based on sequence homology searches such as MSBLASTP2 are most powerful. Subsequent gene ontology and pathway analysis can then utilize sets of identified genes and proteins for modeling molecular mechanisms of environmental adaptation. Current limitations for proteomics in non-model species can be overcome by improving sequence coverage, N- and C-terminal sequencing and analysis of intact proteins. Dependence on information about biochemical pathways and gene ontology databases for model species represents a more severe barrier for work with non-model species. To minimize such dependence, focusing on a single biological process (rather than attempting to describe the system as a whole) is key when applying 'omics' approaches to non-model organisms. PMID:17449824

  8. Role of Heat-Shock Proteins in Cellular Function and in the Biology of Fungi

    PubMed Central

    Tiwari, Shraddha; Thakur, Raman; Shankar, Jata

    2015-01-01

    Stress (biotic or abiotic) is an unfavourable condition for an organism including fungus. To overcome stress, organism expresses heat-shock proteins (Hsps) or chaperons to perform biological function. Hsps are involved in various routine biological processes such as transcription, translation and posttranslational modifications, protein folding, and aggregation and disaggregation of proteins. Thus, it is important to understand holistic role of Hsps in response to stress and other biological conditions in fungi. Hsp104, Hsp70, and Hsp40 are found predominant in replication and Hsp90 is found in transcriptional and posttranscriptional process. Hsp90 and Hsp70 in combination or alone play a major role in morphogenesis and dimorphism. Heat stress in fungi expresses Hsp60, Hsp90, Hsp104, Hsp30, and Hsp10 proteins, whereas expression of Hsp12 protein was observed in response to cold stress. Hsp30, Hsp70, and Hsp90 proteins showed expression in response to pH stress. Osmotic stress is controlled by small heat-shock proteins and Hsp60. Expression of Hsp104 is observed under high pressure conditions. Out of these heat-shock proteins, Hsp90 has been predicted as a potential antifungal target due to its role in morphogenesis. Thus, current review focuses on role of Hsps in fungi during morphogenesis and various stress conditions (temperature, pH, and osmotic pressure) and in antifungal drug tolerance. PMID:26881084

  9. The cytoplasmic peptide:N-glycanase (NGLY1) - Structure, expression and cellular functions.

    PubMed

    Suzuki, Tadashi; Huang, Chengcheng; Fujihira, Haruhiko

    2016-02-10

    NGLY1/Ngly1 is a cytosolic peptide:N-glycanase, i.e. de-N-glycosylating enzyme acting on N-glycoproteins in mammals, generating free, unconjugated N-glycans and deglycosylated peptides in which the N-glycosylated asparagine residues are converted to aspartates. This enzyme is known to be involved in the quality control system for the newly synthesized glycoproteins in the endoplasmic reticulum (ER). In this system, misfolded (glyco)proteins are retrotranslocated to the cytosol, where the 26S proteasomes play a central role in degrading the proteins: a process referred to as ER-associated degradation or ERAD in short. PNGase-mediated deglycosylation is believed to facilitate the efficient degradation of some misfolded glycoproteins. Human patients harboring mutations of NGLY1 gene (NGLY1-deficiency) have recently been discovered, clearly indicating the functional importance of this enzyme. This review summarizes the current state of our knowledge on NGLY1 and its gene product in mammalian cells. PMID:26611529

  10. Comparing exosome-like vesicles with liposomes for the functional cellular delivery of small RNAs.

    PubMed

    Stremersch, Stephan; Vandenbroucke, Roosmarijn E; Van Wonterghem, Elien; Hendrix, An; De Smedt, Stefaan C; Raemdonck, Koen

    2016-06-28

    Exosome-like vesicles (ELVs) play an important role in intercellular communication by acting as natural carriers for biomolecule transfer between cells. This unique feature rationalizes their exploitation as bio-inspired drug delivery systems. However, the therapeutic application of ELVs is hampered by the lack of efficient and reproducible drug loading methods, in particular for therapeutic macromolecules. To overcome this limitation, we present a generic method to attach siRNA to the surface of isolated ELVs by means of a cholesterol anchor. Despite a feasible uptake in both a dendritic and lung epithelial cell line, B16F10- and JAWSII-derived ELVs were unable to functionally deliver the associated small RNAs, neither exogenous cholesterol-conjugated siRNA nor endogenous miRNA derived from the melanoma producer cell. The latter results were confirmed both for purified ELVs and ELVs delivered via a transwell co-culture set-up. In contrast, simple anionic fusogenic liposomes were able to induce a marked siRNA-mediated gene knockdown under equal experimental conditions, both indicating successful cytosolic delivery of surface-bound cholesterol-conjugated siRNA and further underscoring the incapacity of the here evaluated ELVs to guide cytosolic delivery of small RNAs. In conclusion, we demonstrate that a more in-depth understanding of the biomolecular delivery mechanism and specificity is required before ELVs can be envisioned as a generic siRNA carrier. PMID:27072025

  11. Vitamin B6 nutritional status and cellular availability of pyridoxal 5'-phosphate govern the function of the transsulfuration pathway's canonical reactions and hydrogen sulfide production via side reactions.

    PubMed

    Gregory, Jesse F; DeRatt, Barbara N; Rios-Avila, Luisa; Ralat, Maria; Stacpoole, Peter W

    2016-07-01

    The transsulfuration pathway (TS) acts in sulfur amino acid metabolism by contributing to the regulation of cellular homocysteine, cysteine production, and the generation of H2S for signaling functions. Regulation of TS pathway kinetics involves stimulation of cystathionine β-synthase (CBS) by S-adenosylmethionine (SAM) and oxidants such as H2O2, and by Michaelis-Menten principles whereby substrate concentrations affect reaction rates. Although pyridoxal phosphate (PLP) serves as coenzyme for both CBS and cystathionine γ-lyase (CSE), CSE exhibits much greater loss of activity than CBS during PLP insufficiency. Thus, cellular and plasma cystathionine concentrations increase in vitamin B6 deficiency mainly due to the bottleneck caused by reduced CSE activity. Because of the increase in cystathionine, the canonical production of cysteine (homocysteine → cystathionine → cysteine) is largely maintained even during vitamin B6 deficiency. Typical whole body transsulfuration flux in humans is 3-7 μmol/h per kg body weight. The in vivo kinetics of H2S production via side reactions of CBS and CSE in humans are unknown but they have been reported for cultured HepG2 cells. In these studies, cells exhibit a pronounced reduction in H2S production capacity and rates of lanthionine and homolanthionine synthesis in deficiency. In humans, plasma concentrations of lanthionine and homolanthionine exhibit little or no mean change due to 4-wk vitamin B6 restriction, nor do they respond to pyridoxine supplementation of subjects in chronically low-vitamin B6 status. Wide individual variation in responses of the H2S biomarkers to such perturbations of human vitamin B6 status suggests that the resulting modulation of H2S production may have physiological consequences in a subset of people. Supported by NIH grant DK072398. This paper refers to data from studies registered at clinicaltrials.gov as NCT01128244 and NCT00877812. PMID:26765812

  12. Exosome poly-ubiquitin inhibits platelet activation, downregulates CD36, and inhibits pro-atherothombotic cellular functions

    PubMed Central

    Srikanthan, Sowmya; Li, Wei; Silverstein, Roy L.; McIntyre, Thomas M.

    2014-01-01

    Introduction Activated platelets shed microparticles from plasma membranes, but also release smaller exosomes from internal compartments. While microparticles participate in athero-thrombosis, little is known of exosomes in this process. Materials & Methods Ex vivo biochemical experiments with human platelets and exosomes, and FeCl3-induced murine carotid artery thrombosis. Results Both microparticles and exosomes were abundant in human plasma. Platelet-derived exosomes suppressed ex vivo platelet aggregation and reduced adhesion to collagen-coated microfluidic channels at high shear. Injected exosomes inhibited occlusive thrombosis in FeCl3-damaged murine carotid arteries. Control platelets infused into irradiated, thrombocytopenic mice reconstituted thrombosis in damaged carotid arteries, but failed to do so after prior ex vivo incubation with exosomes. CD36 promotes platelet activation, and exosomes dramatically reduced platelet CD36. CD36 is also expressed by macrophages where it binds and internalizes oxidized LDL and microparticles, supplying lipid to promote foam cell formation. Platelet exosomes inhibited oxidized-LDL binding and cholesterol loading into macrophages. Exosomes were not competitive CD36 ligands, but instead sharply reduced total macrophage CD36 content. Exosomal proteins, in contrast to microparticle or cellular proteins, were highly adducted by ubiquitin. Exosomes enhanced ubiquitination of cellular proteins, including CD36, and blockade of proteosome proteolysis with MG-132 rescued CD36 expression. Recombinant unanchored K48 poly-ubiquitin behaved similarly to exosomes, inhibiting platelet function, macrophage CD36 expression, and macrophage particle uptake. Conclusions Platelet-derived exosomes inhibit athero-thrombotic processes by reducing CD36-dependent lipid loading of macrophages and by suppressing platelet thrombosis. Exosomes increase protein ubiquitination, and enhance proteasome degradation of CD36. PMID:25163645

  13. Novel metastasis-related gene CIM functions in the regulation of multiple cellular stress-response pathways.

    PubMed

    Yanagisawa, Kiyoshi; Konishi, Hiroyuki; Arima, Chinatsu; Tomida, Shuta; Takeuchi, Toshiyuki; Shimada, Yukako; Yatabe, Yasushi; Mitsudomi, Tetsuya; Osada, Hirotaka; Takahashi, Takashi

    2010-12-01

    Various stresses of the tumor microenvironment produced by insufficient nutrients, pH, and oxygen can contribute to the generation of altered metabolic and proliferative states that promote the survival of metastatic cells. Among many cellular stress-response pathways activated under such conditions are the hypoxia-inducible factor (HIF) pathway and the unfolded protein response (UPR), which is elicited as a response to endoplasmic reticulum (ER) stress. In this study, we report the identification of a novel cancer invasion and metastasis-related gene (hereafter referred to as CIM, also called ERLEC1), which influences both of these stress-response pathways to promote metastasis. CIM was identified by comparing the gene expression profile of a highly metastatic human lung cancer cell line with its weakly metastatic parental clone. We showed that CIM is critical for metastatic properties in this system. Proteomic approaches combined with bioinformatic analyses revealed that CIM has multifaceted roles in controlling the response to hypoxia and ER stress. Specifically, CIM sequestered OS-9 from the HIF-1α complex and PHD2, permitting HIF-1α accumulation by preventing its degradation. Ectopic expression of CIM in lung cancer cells increased their tolerance to hypoxia. CIM also modulated UPR through interaction with the key ER stress protein BiP, influencing cell proliferation under ER stress conditions. Our findings shed light on how tolerance to multiple cellular stresses at a metastatic site can be evoked by an integrated mechanism involving CIM, which can function to coordinate those responses in a manner that promotes metastatic cell survival. PMID:21118962

  14. Affect and the Brain's Functional Organization: A Resting-State Connectivity Approach

    PubMed Central

    Rohr, Christiane S.; Okon-Singer, Hadas; Craddock, R. Cameron; Villringer, Arno; Margulies, Daniel S.

    2013-01-01

    The question of how affective processing is organized in the brain is still a matter of controversial discussions. Based on previous initial evidence, several suggestions have been put forward regarding the involved brain areas: (a) right-lateralized dominance in emotional processing, (b) hemispheric dominance according to positive or negative valence, (c) one network for all emotional processing and (d) region-specific discrete emotion matching. We examined these hypotheses by investigating intrinsic functional connectivity patterns that covary with results of the Positive and Negative Affective Schedule (PANAS) from 65 participants. This approach has the advantage of being able to test connectivity rather than activation, and not requiring a potentially confounding task. Voxelwise functional connectivity from 200 regions-of-interest covering the whole brain was assessed. Positive and negative affect covaried with functional connectivity involving a shared set of regions, including the medial prefrontal cortex, the anterior cingulate, the visual cortex and the cerebellum. In addition, each affective domain had unique connectivity patterns, and the lateralization index showed a right hemispheric dominance for negative affect. Therefore, our results suggest a predominantly right-hemispheric network with affect-specific elements as the underlying organization of emotional processes. PMID:23935850

  15. Plant Species and Functional Group Combinations Affect Green Roof Ecosystem Functions

    PubMed Central

    Lundholm, Jeremy; MacIvor, J. Scott; MacDougall, Zachary; Ranalli, Melissa

    2010-01-01

    Background Green roofs perform ecosystem services such as summer roof temperature reduction and stormwater capture that directly contribute to lower building energy use and potential economic savings. These services are in turn related to ecosystem functions performed by the vegetation layer such as radiation reflection and transpiration, but little work has examined the role of plant species composition and diversity in improving these functions. Methodology/Principal Findings We used a replicated modular extensive (shallow growing- medium) green roof system planted with monocultures or mixtures containing one, three or five life-forms, to quantify two ecosystem services: summer roof cooling and water capture. We also measured the related ecosystem properties/processes of albedo, evapotranspiration, and the mean and temporal variability of aboveground biomass over four months. Mixtures containing three or five life-form groups, simultaneously optimized several green roof ecosystem functions, outperforming monocultures and single life-form groups, but there was much variation in performance depending on which life-forms were present in the three life-form mixtures. Some mixtures outperformed the best monocultures for water capture, evapotranspiration, and an index combining both water capture and temperature reductions. Combinations of tall forbs, grasses and succulents simultaneously optimized a range of ecosystem performance measures, thus the main benefit of including all three groups was not to maximize any single process but to perform a variety of functions well. Conclusions/Significance Ecosystem services from green roofs can be improved by planting certain life-form groups in combination, directly contributing to climate change mitigation and adaptation strategies. The strong performance by certain mixtures of life-forms, especially tall forbs, grasses and succulents, warrants further investigation into niche complementarity or facilitation as mechanisms

  16. The application of multiple biophysical cues to engineer functional neocartilage for treatment of osteoarthritis. Part I: cellular response.

    PubMed

    Brady, Mariea A; Waldman, Stephen D; Ethier, C Ross

    2015-02-01

    Osteoarthritis (OA) is a complex disease of the joint for which current treatments are unsatisfactory, thus motivating development of tissue engineering (TE)-based therapies. To date, TE strategies have had some success, developing replacement tissue constructs with biochemical properties approaching that of native cartilage. However, poor biomechanical properties and limited postimplantation integration with surrounding tissue are major shortcomings that need to be addressed. Functional tissue engineering strategies that apply physiologically relevant biophysical cues provide a platform to improve TE constructs before implantation. In the previous decade, new experimental and theoretical findings in cartilage biomechanics and electromechanics have emerged, resulting in an increased understanding of the complex interplay of multiple biophysical cues in the extracellular matrix of the tissue. The effect of biophysical stimulation on cartilage, and the resulting chondrocyte-mediated biosynthesis, remodeling, degradation, and repair, has, therefore, been extensively explored by the TE community. This article compares and contrasts the cellular response of chondrocytes to multiple biophysical stimuli, and may be read in conjunction with its companion paper that compares and contrasts the subsequent intracellular signal transduction cascades. Mechanical, magnetic, and electrical stimuli promote proliferation, differentiation, and maturation of chondrocytes within established dose parameters or "biological windows." This knowledge will provide a framework for ongoing studies incorporating multiple biophysical cues in TE functional neocartilage for treatment of OA. PMID:24919456

  17. Study on the effect of polysaccharides from Solanum nigrum Linne on cellular immune function in tumour-bearing mice.

    PubMed

    Chen, Hai; Qi, Xiaodong

    2013-01-01

    We investigated the anti-tumour effect of polysaccharides from Solanum nigrum Linne, and its relationship with the immune function of tumour-bearing organisms. MTT assay was used to observe the effect of different doses of polysaccharides from Solanum nigrum Linne on proliferation of lymphocytes in tumour-bearing mice. ELISA assay was also used to detect the levels of IL-2 in mice, and a laser scanning confocal microscope was used to detect the effect of polysaccharides from Solanum nigrum Linne on intralymphocytic free calcium ion concentration in tumour-bearing mice. Different doses of polysaccharides from Solanum nigrum Linne significantly inhibited the growth of mouse H22 solid tumours, improved the survival time of tumour-bearing mice, increased the proliferation of lymphocytes, elevated the levels of IL-2, and increased the concentration of calcium ions in the lymphocytes. Polysaccharides from Solanum nigrum Linne have certain anti-tumour effect, which is related with the cellular immune function that regulates the body. PMID:24146499

  18. Abr and Bcr, Two Homologous Rac GTPase-Activating Proteins, Control Multiple Cellular Functions of Murine Macrophages▿ †

    PubMed Central

    Cho, Young Jin; Cunnick, Jess M.; Yi, Sun-Ju; Kaartinen, Vesa; Groffen, John; Heisterkamp, Nora

    2007-01-01

    Small GTPases of the Rho family are key regulators of phagocytic leukocyte function. Abr and Bcr are homologous, multidomain proteins. Their C-terminal domain has GTPase-activating protein (GAP) activity that, in vitro, is specific for Rac and Cdc42. To address the in vivo relevance of these entire proteins, of which little is known, the current study examined the effect of the genetic ablation of Abr and Bcr in murine macrophages. The concomitant loss of Abr and Bcr induced multiple alterations of macrophage cellular behavior known to be under the control of Rac. Macrophages lacking both Abr and Bcr exhibited an atypical, elongated morphology that was reproduced by the ectopic expression of GAP domain mutant Abr and Bcr in a macrophage cell line and of constitutively active Rac in primary macrophages. A robust increase in colony-stimulating factor 1 (CSF-1)-directed motility was observed in macrophages deficient for both proteins and, in response to CSF-1 stimulation, Abr and Bcr transiently translocated to the plasma membrane. Phagocytosis of opsonized particles was also increased in macrophages lacking both proteins and correlated with sustained Rac activation. Bcr and Abr GAP mutant proteins localized around phagosomes and induced distinct phagocytic cup formation. These results identify Abr and Bcr as the only GAPs to date that specifically negatively regulate Rac function in vivo in primary macrophages. PMID:17116687

  19. Cellular interactions and stimulated biological functions mediated by nanostructured carbon for tissue reconstruction and tracheal tubes and sutures.

    PubMed

    Misra, R D K; Chaudhari, P M

    2013-02-01

    Nylon 6,6 is used for biological applications including gastrointestinal segments, tracheal tubes and sutures, vascular graft, and for hard tissue reconstruction. While it is a relatively inexpensive polymer, it is not widely acceptable as a preferred biomaterial because of bioactivity. To this end, we have discovered the exciting evidence that introduction of a novel nanostructured carbon, graphene, in the void space between the nylon chains and processing at elevated pressure favorably stimulates cellular functions and provides high degree of cytocompatibility. The cell-substrate interactions on stand alone Nylon 6,6 and Nylon 6,6-graphene oxide hybrid system were investigated in terms of cell attachment, viability, proliferation, and assessment of proteins, actin, vinculin, and fibronectin. The enhanced biological functions in the nanostructured hybrid system are attributed to relatively superior hydrophilicity of the surface and to the presence of graphene. Furthermore, it is proposed that the negatively charged graphene interacts with the polar nature of cells and the culture medium, such that the interaction is promoted through polar forces. This is accomplished by investigating cell attachment, proliferation, and morphology, including cytomorphometry evaluation, and quantitative assessment of prominent proteins, actin, vinculin, and fibronectin that are sensitive to cell-substrate interactions. Osteoblasts were studied to establish the practical viability of the hybrid nanostructured biomaterial. The study strengthens the foundation for utilizing nano- or quantum-size effects of nanostructured biomaterials. PMID:22927360

  20. Toxicity of Functional Nano-Micro Zinc Oxide Tetrapods: Impact of Cell Culture Conditions, Cellular Age and Material Properties

    PubMed Central

    Papavlassopoulos, Heike; Mishra, Yogendra K.; Kaps, Sören; Paulowicz, Ingo; Abdelaziz, Ramzy; Elbahri, Mady; Maser, Edmund; Adelung, Rainer; Röhl, Claudia

    2014-01-01

    With increasing production and applications of nanostructured zinc oxide, e.g., for biomedical and consumer products, the question of safety is getting more and more important. Different morphologies of zinc oxide structures have been synthesized and accordingly investigated. In this study, we have particularly focused on nano-micro ZnO tetrapods (ZnO-T), because their large scale fabrication has been made possible by a newly introduced flame transport synthesis approach which will probably lead to several new applications. Moreover, ZnO-T provide a completely different morphology then classical spherical ZnO nanoparticles. To get a better understanding of parameters that affect the interactions between ZnO-T and mammalian cells, and thus their biocompatibility, we have examined the impact of cell culture conditions as well as of material properties on cytotoxicity. Our results demonstrate that the cell density of fibroblasts in culture along with their age, i.e., the number of preceding cell divisions, strongly affect the cytotoxic potency of ZnO-T. Concerning the material properties, the toxic potency of ZnO-T is found to be significantly lower than that of spherical ZnO nanoparticles. Furthermore, the morphology of the ZnO-T influenced cellular toxicity in contrast to surface charges modified by UV illumination or O2 treatment and to the material age. Finally, we have observed that direct contact between tetrapods and cells increases their toxicity compared to transwell culture models which allow only an indirect effect via released zinc ions. The results reveal several parameters that can be of importance for the assessment of ZnO-T toxicity in cell cultures and for particle development. PMID:24454775

  1. Pressuromodulation at the cell membrane as the basis for small molecule hormone and peptide regulation of cellular and nuclear function.

    PubMed

    Sarin, Hemant

    2015-01-01

    Building on recent knowledge that the specificity of the biological interactions of small molecule hydrophiles and lipophiles across microvascular and epithelial barriers, and with cells, can be predicted on the basis of their conserved biophysical properties, and the knowledge that biological peptides are cell membrane impermeant, it has been further discussed herein that cellular, and thus, nuclear function, are primarily regulated by small molecule hormone and peptide/factor interactions at the cell membrane (CM) receptors. The means of regulating cellular, and thus, nuclear function, are the various forms of CM Pressuromodulation that exist, which include Direct CM Receptor-Mediated Stabilizing Pressuromodulation, sub-classified as Direct CM Receptor-Mediated Stabilizing Shift Pressuromodulation (Single, Dual or Tri) or Direct CM Receptor-Mediated Stabilizing Shift Pressuromodulation (Single, Dual or Tri) cum External Cationomodulation (≥3+ → 1+); which are with respect to acute CM receptor-stabilizing effects of small biomolecule hormones, growth factors or cytokines, and also include Indirect CM- or CM Receptor-Mediated Pressuromodulation, sub-classified as Indirect 1ary CM-Mediated Shift Pressuromodulation (Perturbomodulation), Indirect 2ary CM Receptor-Mediated Shift Pressuromodulation (Tri or Quad Receptor Internal Pseudo-Cationomodulation: SS 1+), Indirect 3ary CM Receptor-Mediated Shift Pressuromodulation (Single or Dual Receptor Endocytic External Cationomodulation: 2+) or Indirect (Pseudo) 3ary CM Receptor-Mediated Shift Pressuromodulation (Receptor Endocytic Hydroxylocarbonyloetheroylomodulation: 0), which are with respect to sub-acute CM receptor-stabilizing effects of small biomolecules, growth factors or cytokines. As a generalization, all forms of CM pressuromodulation decrease CM and nuclear membrane (NM) compliance (whole cell compliance), due to pressuromodulation of the intracellular microtubule network and increases the exocytosis of pre

  2. CFH Variants Affect Structural and Functional Brain Changes and Genetic Risk of Alzheimer's Disease.

    PubMed

    Zhang, Deng-Feng; Li, Jin; Wu, Huan; Cui, Yue; Bi, Rui; Zhou, He-Jiang; Wang, Hui-Zhen; Zhang, Chen; Wang, Dong; Kong, Qing-Peng; Li, Tao; Fang, Yiru; Jiang, Tianzi; Yao, Yong-Gang

    2016-03-01

    The immune response is highly active in Alzheimer's disease (AD). Identification of genetic risk contributed by immune genes to AD may provide essential insight for the prognosis, diagnosis, and treatment of this neurodegenerative disease. In this study, we performed a genetic screening for AD-related top immune genes identified in Europeans in a Chinese cohort, followed by a multiple-stage study focusing on Complement Factor H (CFH) gene. Effects of the risk SNPs on AD-related neuroimaging endophenotypes were evaluated through magnetic resonance imaging scan, and the effects on AD cerebrospinal fluid biomarkers (CSF) and CFH expression changes were measured in aged and AD brain tissues and AD cellular models. Our results showed that the AD-associated top immune genes reported in Europeans (CR1, CD33, CLU, and TREML2) have weak effects in Chinese, whereas CFH showed strong effects. In particular, rs1061170 (P(meta)=5.0 × 10(-4)) and rs800292 (P(meta)=1.3 × 10(-5)) showed robust associations with AD, which were confirmed in multiple world-wide sample sets (4317 cases and 16 795 controls). Rs1061170 (P=2.5 × 10(-3)) and rs800292 (P=4.7 × 10(-4)) risk-allele carriers have an increased entorhinal thickness in their young age and a higher atrophy rate as the disease progresses. Rs800292 risk-allele carriers have higher CSF tau and Aβ levels and severe cognitive decline. CFH expression level, which was affected by the risk-alleles, was increased in AD brains and cellular models. These comprehensive analyses suggested that CFH is an important immune factor in AD and affects multiple pathological changes in early life and during disease progress. PMID:26243271

  3. Cellular uptake of poly(allylamine hydrochloride) microcapsules with different deformability and its influence on cell functions.

    PubMed

    Yu, Wei; Zhang, Wenbo; Chen, Ying; Song, Xiaoxue; Tong, Weijun; Mao, Zhengwei; Gao, Changyou

    2016-03-01

    It is important to understand the safety issue and cell interaction pattern of polyelectrolyte microcapsules with different deformability before their use in biomedical applications. In this study, SiO2, poly(sodium-p-styrenesulfonate) (PSS) doped CaCO3 and porous CaCO3 spheres, all about 4μm in diameter, were used as templates to prepare microcapsules with different inner structure and subsequent deformability. As a result, three kinds of covalently assembled poly(allylaminehydrochloride)/glutaraldehyde (PAH/GA) microcapsules with similar size but different deformability under external osmotic pressure were prepared. The impact of different microcapsules on cell viability and functions are studied using smooth muscle cells (SMCs), endothelial cells (ECs) and HepG2 cells. The results demonstrated that viabilities of SMCs, ECs and HepG2 cells were not significantly influenced by either of the three kinds of microcapsules. However, the adhesion ability of SMCs and ECs as well as the mobility of SMCs, ECs and HepG2 cells were significantly impaired after treatment with microcapsules in a deformability dependent manner, especially the microcapsules with lower deformability caused higher impairment on cell functions. The cellular uptake kinetics, uptake pathways, intracellular distribution of microcapsules are further investigated in SMCs to reveal the potential mechanism. The SMCs showed faster uptake rate and exocytosis rate of microcapsules with lower deformability (Cap@CaCO3/PSS and Cap@CaCO3), leading to higher intracellular accumulation of microcapsules with lower deformability and possibly larger retardation of cell functions. The results pointed out that the deformability of microcapsules is an important factor governing the biological performance of microcapsules, which requires careful adjustment for further biomedical applications. PMID:26674230

  4. How do changes to plate thickness, length, and face-connectivity affect femoral cancellous bone's density and surface area? An investigation using regular cellular models.

    PubMed

    Anderson, I A; Carman, J B

    2000-03-01

    Models of regular cellular-solids representing femoral head 'medial group' bone were used to (1) compare thickness data for plate-like and beam-like structures at realistic surface areas and densities; (2) test the validity of a standard formula for trabecular thickness (Tb.Th); and (3) study how systematic changes in cancellous bone thicknesses, spacing, and face-connectivity affect relative density and surface area. Models of different face-connectivities, produced by plate removal from the unit cell, were fitted to bone density and surface area data. The medial group bone was anisotropic: the supero-inferior (SI) direction was the principal direction for bone plate alignment and the plane normal to this had the largest number of bone/void intersections per unit line length (P(I)). A comparison of boundary perimeter per unit area data, in planes normal to SI, with surface area data placed the medial group bone between prismatic structures in which walls are parallel to one principal direction and isotropic structures. Selective removal of plates from a closed-cell model produced a similar result. For the same relative density and surface-area, plate-like models had significantly thinner cross-sections than beam-like models. The formula for Tb.Th produced overestimates of model plate thickness by up to 20% at realistic femoral cancellous densities. Trends in data on surface area to volume ratio and density observed on sampled medial group bone could be simulated by plate thickness changes on models of intermediate face-connectivity (approximately 1.5) or by plate removal from models with relatively thick and short (low aspect-ratio) plates. The latter mechanism is unrealistic for it resulted in beam-like structures at low 'medial group' densities, an architecture unlike the predominantly plate-like bone in the sample. PMID:10673116

  5. Acute Zonal Occult Outer Retinopathy in Japanese Patients: Clinical Features, Visual Function, and Factors Affecting Visual Function

    PubMed Central

    Saito, Saho; Saito, Wataru; Saito, Michiyuki; Hashimoto, Yuki; Mori, Shohei; Noda, Kousuke; Namba, Kenichi; Ishida, Susumu

    2015-01-01

    Purpose To evaluate the clinical features and investigate their relationship with visual function in Japanese patients with acute zonal occult outer retinopathy (AZOOR). Methods Fifty-two eyes of 38 Japanese AZOOR patients (31 female and 7 male patients; mean age at first visit, 35.0 years; median follow-up duration, 31 months) were retrospectively collected: 31 untreated eyes with good visual acuity and 21 systemic corticosteroid-treated eyes with progressive visual acuity loss. Variables affecting the logMAR values of best-corrected visual acuity (BCVA) and the mean deviation (MD) on Humphrey perimetry at initial and final visits were examined using multiple stepwise linear regression analysis. Results In untreated eyes, the mean MD at the final visit was significantly higher than that at the initial visit (P = 0.00002). In corticosteroid-treated eyes, the logMAR BCVA and MD at the final visit were significantly better than the initial values (P = 0.007 and P = 0.02, respectively). The final logMAR BCVA was 0.0 or less in 85% of patients. Variables affecting initial visual function were moderate anterior vitreous cells, myopia severity, and a-wave amplitudes on electroretinography; factors affecting final visual function were the initial MD values, female sex, moderate anterior vitreous cells, and retinal atrophy. Conclusions Our data indicated that visual functions in enrolled patients significantly improved spontaneously or after systemic corticosteroids therapy, suggesting that Japanese patients with AZOOR have good visual outcomes during the follow-up period of this study. Furthermore, initial visual field defects, gender, anterior vitreous cells, and retinal atrophy affected final visual functions in these patients. PMID:25919689

  6. Metacognitive Awareness of Facial Affect in Higher-Functioning Children and Adolescents with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    McMahon, Camilla M.; Henderson, Heather A.; Newell, Lisa; Jaime, Mark; Mundy, Peter

    2016-01-01

    Higher-functioning participants with and without autism spectrum disorder (ASD) viewed a series of face stimuli, made decisions regarding the affect of each face, and indicated their confidence in each decision. Confidence significantly predicted accuracy across all participants, but this relation was stronger for participants with typical…

  7. Automatic Processing of Emotional Faces in High-Functioning Pervasive Developmental Disorders: An Affective Priming Study

    ERIC Educational Resources Information Center

    Kamio, Yoko; Wolf, Julie; Fein, Deborah

    2006-01-01

    This study examined automatic processing of emotional faces in individuals with high-functioning Pervasive Developmental Disorders (HFPDD) using an affective priming paradigm. Sixteen participants (HFPDD and matched controls) were presented with happy faces, fearful faces or objects in both subliminal and supraliminal exposure conditions, followed…

  8. Handgrip Strength, Positive Affect, and Perceived Health Are Prospectively Associated with Fewer Functional Limitations among Centenarians

    ERIC Educational Resources Information Center

    Franke, Warren D.; Margrett, Jennifer A.; Heinz, Melinda; Martin, Peter

    2012-01-01

    This study assessed the association between perceived health, fatigue, positive and negative affect, handgrip strength, objectively measured physical activity, body mass index, and self-reported functional limitations, assessed 6 months later, among 11 centenarians (age = 102 plus or minus 1). Activities of daily living, assessed 6 months prior to…

  9. Weight Reduction in Athletes May Adversely Affect the Phagocytic Function of Monocytes.

    ERIC Educational Resources Information Center

    Kono, Ichiro; And Others

    1988-01-01

    Study of the monocyte phagocytic function in nine competitive athletes before and after a two-week weight reduction (through calorie restriction) program revealed that their pre-program phagocytic activity was higher than in sedentary controls but decreased significantly after the program. This suggests calorie restriction may affect the human…

  10. Cobalt and chromium exposure affects osteoblast function and impairs the mineralization of prosthesis surfaces in vitro.

    PubMed

    Shah, Karan M; Wilkinson, Jeremy Mark; Gartland, Alison

    2015-11-01

    Cobalt (Co) and chromium (Cr) ions and nanoparticles equivalent to those released through tribo-corrosion of prosthetic metal-on-metal (MOM) bearings and taper junctions are detrimental to osteoblast activity and function in vitro when examined as individual species. Here we examined the effects of Co(2+):Cr(3+) and Co(2+):Cr(6+) combinations on osteoblast-like SaOS-2 cellular activity, alkaline phosphatase (ALP) activity and mineralization to better reflect clinical exposure conditions in vivo. We also assessed the effect of Co(2+):Cr(3+) combinations and Co:Cr nanoparticles on SaOS-2 cell osteogenic responses on grit-blasted, plasma-sprayed titanium-coated, and hydroxyapatite-coated prosthesis surfaces. Cellular activity and ALP activity were reduced to a greater extent with combination treatments compared to individual ions. Co(2+) and Cr(3+) interacted additively and synergistically to reduce cellular activity and ALP activity, respectively, while the Co(2+) with Cr(6+) combination was dominated by the effect of Cr(6+) alone. Mineralization by osteoblasts was greater on hydroxyapatite-coated surfaces compared to grit-blasted and plasma-sprayed titanium-coated surfaces. Treatments with Co(2+):Cr(3+) ions and Co:Cr nanoparticles reduced the percentage mineralization on all surfaces, with hydroxyapatite-coated surfaces having the least reduction. In conclusion, our data suggests that previous studies investigating individual metal ions underestimate their potential clinical effects on osteoblast activity. Furthermore, the data suggests that hydroxyapatite-coated surfaces may modulate osteoblast responses to metal debris. PMID:25929464

  11. Regulatory and effector functions of gamma-delta (γδ) T cells and their therapeutic potential in adoptive cellular therapy for cancer.

    PubMed

    Paul, Sourav; Lal, Girdhari

    2016-09-01

    γδ T cells are an important innate immune component of the tumor microenvironment and are known to affect the immune response in a wide variety of tumors. Unlike αβ T cells, γδ T cells are capable of spontaneous secretion of IL-17A and IFN-γ without undergoing clonal expansion. Although γδ T cells do not require self-MHC-restricted priming, they can distinguish "foreign" or transformed cells from healthy self-cells by using activating and inhibitory killer Ig-like receptors. γδ T cells were used in several clinical trials to treat cancer patient due to their MHC-unrestricted cytotoxicity, ability to distinguish transformed cells from normal cells, the capacity to secrete inflammatory cytokines and also their ability to enhance the generation of antigen-specific CD8(+) and CD4(+) T cell response. In this review, we discuss the effector and regulatory function of γδ T cells in the tumor microenvironment with special emphasis on the potential for their use in adoptive cellular immunotherapy. PMID:27012367

  12. D77, one benzoic acid derivative, functions as a novel anti-HIV-1 inhibitor targeting the interaction between integrase and cellular LEDGF/p75

    SciTech Connect

    Du Li; Zhao Yaxue; Chen, Jing; Yang Liumeng; Zheng Yongtang; Tang Yun Shen Xu Jiang Hualiang

    2008-10-10

    Integration of viral-DNA into host chromosome mediated by the viral protein HIV-1 integrase (IN) is an essential step in the HIV-1 life cycle. In this process, Lens epithelium-derived growth factor (LEDGF/p75) is discovered to function as a cellular co-factor for integration. Since LEDGF/p75 plays an important role in HIV integration, disruption of the LEDGF/p75 interaction with IN has provided a special interest for anti-HIV agent discovery. In this work, we reported that a benzoic acid derivative, 4-[(5-bromo-4-{l_brace}[2,4-dioxo-3-(2-oxo-2-phenylethyl) -1,3-thiazolidin-5-ylidene]methyl{r_brace}-2-ethoxyphenoxy)methyl]benzoic acid (D77) could potently inhibit the IN-LEDGF/p75 interaction and affect the HIV-1 IN nuclear distribution thus exhibiting antiretroviral activity. Molecular docking with site-directed mutagenesis analysis and surface plasmon resonance (SPR) binding assays has clarified possible binding mode of D77 against HIV-1 integrase. As the firstly discovered small molecular compound targeting HIV-1 integrase interaction with LEDGF/p75, D77 might supply useful structural information for further anti-HIV agent discovery.

  13. Automatic facial responses to affective stimuli in high-functioning adults with autism spectrum disorder.

    PubMed

    Mathersul, Danielle; McDonald, Skye; Rushby, Jacqueline A

    2013-01-17

    Individuals with autism spectrum disorder (ASD) demonstrate atypical behavioural responses to affective stimuli, although the underlying mechanisms remain unclear. Investigating automatic responses to these stimuli may help elucidate these mechanisms. 18 high-functioning adults with ASDs and 18 typically developing controls viewed 54 extreme pleasant (erotica), extreme unpleasant (mutilations), and non-social neutral images from the International Affective Picture System (IAPS). Two-thirds of images received an acoustic startle probe 3s post-picture onset. Facial electromyography (EMG) activity (orbicularis, zygomaticus, corrugator), skin conductance (SCR) and cardiac responses were recorded. The adults with ASDs demonstrated typical affective startle modulation and automatic facial EMG responses but atypical autonomic (SCRs and cardiac) responses, suggesting a failure to orient to, or a deliberate effort to disconnect from, socially relevant stimuli (erotica, mutilations). These results have implications for neural systems known to underlie affective processes, including the orbitofrontal cortex and amygdala. PMID:23142408

  14. Robust passive and active efflux of cellular cholesterol to a designer functional mimic of high density lipoprotein

    PubMed Central

    Luthi, Andrea J.; Lyssenko, Nicholas N.; Quach, Duyen; McMahon, Kaylin M.; Millar, John S.; Vickers, Kasey C.; Rader, Daniel J.; Phillips, Michael C.; Mirkin, Chad A.; Thaxton, C. Shad

    2015-01-01

    The ability of HDL to support macrophage cholesterol efflux is an integral part of its atheroprotective action. Augmenting this ability, especially when HDL cholesterol efflux capacity from macrophages is poor, represents a promising therapeutic strategy. One approach to enhancing macrophage cholesterol efflux is infusing blood with HDL mimics. Previously, we reported the synthesis of a functional mimic of HDL (fmHDL) that consists of a gold nanoparticle template, a phospholipid bilayer, and apo A-I. In this work, we characterize the ability of fmHDL to support the well-established pathways of cellular cholesterol efflux from model cell lines and primary macrophages. fmHDL received cell cholesterol by unmediated (aqueous) and ABCG1- and scavenger receptor class B type I (SR-BI)-mediated diffusion. Furthermore, the fmHDL holoparticle accepted cholesterol and phospholipid by the ABCA1 pathway. These results demonstrate that fmHDL supports all the cholesterol efflux pathways available to native HDL and thus, represents a promising infusible therapeutic for enhancing macrophage cholesterol efflux. fmHDL accepts cholesterol from cells by all known pathways of cholesterol efflux: unmediated, ABCG1- and SR-BI-mediated diffusion, and through ABCA1. PMID:25652088

  15. [The influence to the function of cellular immunity after being infected by HBV in the PBMC in chronic hepatitis B].

    PubMed

    Xuan, S Y; Sun, Y; Zhang, J

    1997-04-01

    In this study, HBV DNA was detected by PCR from PBMC of chronic hepatitis B. A total number of 54 cases were positive and 71 cases were negative. When detecting the competence of NK cells, the subgroup of T cells the ratio of CD4/CD8, the concentration of sIL-2R in three groups, and between the two CHB groups and a normal control group, the differences between HBV DNA positive group and HBV DNA negative group and between HBVDNA positive group and the normal control group were all dramatically significant (P < 0.01). We also found that a lineal correlation of the competence of NK cells, the ratio of CD4/CD8 and the concentration of sIL-2R(P < 0.01) in the positive group, whereas in the negative group only the ratio of CD4/CD8 was consistent with the concentration of sIL-2R(P < 0.01), and the competence of NK cells did not decrease obviously. The results indicated that it was the infection of HBV in PBMC which caused the disorder of the function of cellular immunity. This finding helped us to explain the pathogenesis of hepatitis B. It could also lay a theoretical ground for the prevention and the treatment of hepatitis B. PMID:9812503

  16. Robust passive and active efflux of cellular cholesterol to a designer functional mimic of high density lipoprotein.

    PubMed

    Luthi, Andrea J; Lyssenko, Nicholas N; Quach, Duyen; McMahon, Kaylin M; Millar, John S; Vickers, Kasey C; Rader, Daniel J; Phillips, Michael C; Mirkin, Chad A; Thaxton, C Shad

    2015-05-01

    The ability of HDL to support macrophage cholesterol efflux is an integral part of its atheroprotective action. Augmenting this ability, especially when HDL cholesterol efflux capacity from macrophages is poor, represents a promising therapeutic strategy. One approach to enhancing macrophage cholesterol efflux is infusing blood with HDL mimics. Previously, we reported the synthesis of a functional mimic of HDL (fmHDL) that consists of a gold nanoparticle template, a phospholipid bilayer, and apo A-I. In this work, we characterize the ability of fmHDL to support the well-established pathways of cellular cholesterol efflux from model cell lines and primary macrophages. fmHDL received cell cholesterol by unmediated (aqueous) and ABCG1- and scavenger receptor class B type I (SR-BI)-mediated diffusion. Furthermore, the fmHDL holoparticle accepted cholesterol and phospholipid by the ABCA1 pathway. These results demonstrate that fmHDL supports all the cholesterol efflux pathways available to native HDL and thus, represents a promising infusible therapeutic for enhancing macrophage cholesterol efflux. fmHDL accepts cholesterol from cells by all known pathways of cholesterol efflux: unmediated, ABCG1- and SR-BI-mediated diffusion, and through ABCA1. PMID:25652088

  17. Spontaneous Mesotheliomas in F344/N Rats are Characterized by Dysregulation of Cellular Growth and Immune Function Pathways

    PubMed Central

    Blackshear, Pamela E.; Pandiri, Arun R.; Ton, Thai-Vu T.; Clayton, Natasha P.; Shockley, Keith R.; Peddada, Shyamal D.; Gerrish, Kevin E.; Sills, Robert C.; Hoenerhoff, Mark J.

    2016-01-01

    Aged male Fischer 344/N rats are prone to developing spontaneous peritoneal mesotheliomas, which arise predominantly from the tunica vaginalis of the testes. A definitive cause for the predominance of this neoplasm in F344/N rats is unknown. Investigation of the molecular alterations that occur in spontaneous rat mesotheliomas may provide insight into their pathogenesis, as well enable a better understanding regarding the mechanisms underlying chemically induced mesothelioma in rodents. Mesothelial cell function represents a complex interplay of pathways related to host defense mechanisms and maintenance of cellular homeostasis. Global gene expression profiles of spontaneous mesotheliomas from vehicle control male F344/N rats from two-year National Toxicology Program carcinogenicity bioassays were analyzed to determine the molecular features of these tumors, and elucidate tumor-specific gene expression profiles. The resulting gene expression pattern showed that spontaneous mesotheliomas are associated with upregulation various growth factors, oncogenes, cytokines, pattern recognition response receptors (PRR) and pathogen associated molecular patterns (PAMP) receptors, and the production of reactive oxygen and nitrogen species, as well as downregulation of apoptosis pathways. Alterations in these pathways in turn trigger molecular responses that stimulate cell proliferation and promote tumor survival and progression. PMID:23980201

  18. Small but Powerful: Top Predator Local Extinction Affects Ecosystem Structure and Function in an Intermittent Stream

    PubMed Central

    Rodríguez-Lozano, Pablo; Verkaik, Iraima; Rieradevall, Maria; Prat, Narcís

    2015-01-01

    Top predator loss is a major global problem, with a current trend in biodiversity loss towards high trophic levels that modifies most ecosystems worldwide. Most research in this area is focused on large-bodied predators, despite the high extinction risk of small-bodied freshwater fish that often act as apex consumers. Consequently, it remains unknown if intermittent streams are affected by the consequences of top-predators’ extirpations. The aim of our research was to determine how this global problem affects intermittent streams and, in particular, if the loss of a small-bodied top predator (1) leads to a ‘mesopredator release’, affects primary consumers and changes whole community structures, and (2) triggers a cascade effect modifying the ecosystem function. To address these questions, we studied the top-down effects of a small endangered fish species, Barbus meridionalis (the Mediterranean barbel), conducting an enclosure/exclosure mesocosm experiment in an intermittent stream where B. meridionalis became locally extinct following a wildfire. We found that top predator absence led to ‘mesopredator release’, and also to ‘prey release’ despite intraguild predation, which contrasts with traditional food web theory. In addition, B. meridionalis extirpation changed whole macroinvertebrate community composition and increased total macroinvertebrate density. Regarding ecosystem function, periphyton primary production decreased in apex consumer absence. In this study, the apex consumer was functionally irreplaceable; its local extinction led to the loss of an important functional role that resulted in major changes to the ecosystem’s structure and function. This study evidences that intermittent streams can be affected by the consequences of apex consumers’ extinctions, and that the loss of small-bodied top predators can lead to large ecosystem changes. We recommend the reintroduction of small-bodied apex consumers to systems where they have been

  19. Small but powerful: top predator local extinction affects ecosystem structure and function in an intermittent stream.

    PubMed

    Rodríguez-Lozano, Pablo; Verkaik, Iraima; Rieradevall, Maria; Prat, Narcís

    2015-01-01

    Top predator loss is a major global problem, with a current trend in biodiversity loss towards high trophic levels that modifies most ecosystems worldwide. Most research in this area is focused on large-bodied predators, despite the high extinction risk of small-bodied freshwater fish that often act as apex consumers. Consequently, it remains unknown if intermittent streams are affected by the consequences of top-predators' extirpations. The aim of our research was to determine how this global problem affects intermittent streams and, in particular, if the loss of a small-bodied top predator (1) leads to a 'mesopredator release', affects primary consumers and changes whole community structures, and (2) triggers a cascade effect modifying the ecosystem function. To address these questions, we studied the top-down effects of a small endangered fish species, Barbus meridionalis (the Mediterranean barbel), conducting an enclosure/exclosure mesocosm experiment in an intermittent stream where B. meridionalis became locally extinct following a wildfire. We found that top predator absence led to 'mesopredator release', and also to 'prey release' despite intraguild predation, which contrasts with traditional food web theory. In addition, B. meridionalis extirpation changed whole macroinvertebrate community composition and increased total macroinvertebrate density. Regarding ecosystem function, periphyton primary production decreased in apex consumer absence. In this study, the apex consumer was functionally irreplaceable; its local extinction led to the loss of an important functional role that resulted in major changes to the ecosystem's structure and function. This study evidences that intermittent streams can be affected by the consequences of apex consumers' extinctions, and that the loss of small-bodied top predators can lead to large ecosystem changes. We recommend the reintroduction of small-bodied apex consumers to systems where they have been extirpated, to restore

  20. Cholinergic and serotonergic modulations differentially affect large-scale functional networks in the mouse brain.

    PubMed

    Shah, Disha; Blockx, Ines; Keliris, Georgios A; Kara, Firat; Jonckers, Elisabeth; Verhoye, Marleen; Van der Linden, Annemie

    2016-07-01

    Resting-state functional MRI (rsfMRI) is a widely implemented technique used to investigate large-scale topology in the human brain during health and disease. Studies in mice provide additional advantages, including the possibility to flexibly modulate the brain by pharmacological or genetic manipulations in combination with high-throughput functional connectivity (FC) investigations. Pharmacological modulations that target specific neurotransmitter systems, partly mimicking the effect of pathological events, could allow discriminating the effect of specific systems on functional network disruptions. The current study investigated the effect of cholinergic and serotonergic antagonists on large-scale brain networks in mice. The cholinergic system is involved in cognitive functions and is impaired in, e.g., Alzheimer's disease, while the serotonergic system is involved in emotional and introspective functions and is impaired in, e.g., Alzheimer's disease, depression and autism. Specific interest goes to the default-mode-network (DMN), which is studied extensively in humans and is affected in many neurological disorders. The results show that both cholinergic and serotonergic antagonists impaired the mouse DMN-like network similarly, except that cholinergic modulation additionally affected the retrosplenial cortex. This suggests that both neurotransmitter systems are involved in maintaining integrity of FC within the DMN-like network in mice. Cholinergic and serotonergic modulations also affected other functional networks, however, serotonergic modulation impaired the frontal and thalamus networks more extensively. In conclusion, this study demonstrates the utility of pharmacological rsfMRI in animal models to provide insights into the role of specific neurotransmitter systems on functional networks in neurological disorders. PMID:26195064

  1. An investigation on pharmacy functions and services affecting satisfaction of patients with prescriptions in community pharmacies.

    PubMed

    Sakurai, Hidehiko; Nakajima, Fumio; Tada, Yuichirou; Yoshikawa, Emi; Iwahashi, Yoshiki; Fujita, Kenji; Hayase, Yukitoshi

    2009-05-01

    Various functions expected by patient expects are needed with progress in the system for separation of dispensing and prescribing functions. In this investigation, the relationship between patient satisfaction and pharmacy function were analyzed quantitatively. A questionnaire survey was conducted in 178 community pharmacies. Questions on pharmacy functions and services totaled 87 items concerning information service, amenities, safety, personnel training, etc. The questionnaires for patients had five-grade scales and composed 11 items (observed variables). Based on the results, "the percentage of satisfied patients" was determined. Multivariate analysis was performed to investigate the relationship between patient satisfaction and pharmacy functions or services provided, to confirm patient's evaluation of the pharmacy, and how factors affected comprehensive satisfaction. In correlation analysis, "the number of pharmacists" and "comprehensive satisfaction" had a negative correlation. Other interesting results were obtained. As a results of factor analysis, three latent factors were obtained: the "human factor," "patients' convenience," and "environmental factor," Multiple regression analysis showed that the "human factor" affected "comprehensive satisfaction" the most. Various pharmacy functions and services influence patient satisfaction, and improvement in their quality increases patient satisfaction. This will result in the practice of patient-centered medicine. PMID:19420889

  2. Functions and sources of perceived social support among children affected by HIV/AIDS in China.

    PubMed

    Zhao, Guoxiang; Li, Xiaoming; Fang, Xiaoyi; Zhao, Junfeng; Hong, Yan; Lin, Xiuyun; Stanton, Bonita

    2011-06-01

    While the relationship between perceived social support (PSS) and psychosocial well-being has been well documented in the global literature, existing studies also suggest the existence of multiple domains in definition and measurement of PSS. The current study, utilizing data from 1299 rural children affected by HIV/AIDS in central China, examines the relative importance of PSS functional measures (informational/emotional, material/tangible, affectionate, and social interaction) and PSS structural measures (family/relatives, teachers, friends, and significant others) in predicting psychosocial outcomes including internalizing problems, externalizing problems, and educational resilience. Both functional and structural measures of PSS provided reliable measures of related but unique aspects of PSS. The findings of the current study confirmed the previous results that PSS is highly correlated with children's psychosocial well-being and such correlations vary by functions and sources of the PSS as well as different psychosocial outcomes. The findings in the current study suggested the roles of specific social support functions or resources may need to be assessed in relation to specific psychosocial outcome and the context of children's lives. The strong association between PSS and psychosocial outcomes underscores the importance of adequate social support to alleviate stressful life events and improve psychosocial well-being of children affected by HIV/AIDS. Meanwhile, the study findings call for gender and developmentally appropriate and situation-specific social support for children and families affected by HIV/AIDS. PMID:21287421

  3. Cognitive Function in Adolescent Patients with Anorexia Nervosa and Unipolar Affective Disorders.

    PubMed

    Sarrar, Lea; Holzhausen, Martin; Warschburger, Petra; Pfeiffer, Ernst; Lehmkuhl, Ulrike; Schneider, Nora

    2016-05-01

    Studies have shown impairments in cognitive function among adult patients with anorexia nervosa (AN) and affective disorders (AD). The association between cognitive dysfunctions, AN and AD as well as the specificity for these psychiatric diagnoses remains unclear. Therefore, we examined cognitive flexibility and processing speed in 47 female adolescent patients with AN, 21 female adolescent patients with unipolar affective disorders and 48 female healthy adolescents. All participants completed a neuropsychological test battery. There were no significant group differences regarding cognitive function, except for psychomotor processing speed with poorer performance in patients with AN. A further analysis revealed that all groups performed with the normal range, although patients with AN were over represented in the poorest performing quartile. We found no severe cognitive impairments in either patient group. Nevertheless, belonging to the AN group contributed significantly to poor performances in neuropsychological tasks. Therefore, we conclude that the risk for cognitive impairments is slightly higher for patients with AN. PMID:26695683

  4. The relationship between sleep-wake cycle and cognitive functioning in young people with affective disorders.

    PubMed

    Carpenter, Joanne S; Robillard, Rébecca; Lee, Rico S C; Hermens, Daniel F; Naismith, Sharon L; White, Django; Whitwell, Bradley; Scott, Elizabeth M; Hickie, Ian B

    2015-01-01

    Although early-stage affective disorders are associated with both cognitive dysfunction and sleep-wake disruptions, relationships between these factors have not been specifically examined in young adults. Sleep and circadian rhythm disturbances in those with affective disorders are considerably heterogeneous, and may not relate to cognitive dysfunction in a simple linear fashion. This study aimed to characterise profiles of sleep and circadian disturbance in young people with affective disorders and examine associations between these profiles and cognitive performance. Actigraphy monitoring was completed in 152 young people (16-30 years; 66% female) with primary diagnoses of affective disorders, and 69 healthy controls (18-30 years; 57% female). Patients also underwent detailed neuropsychological assessment. Actigraphy data were processed to estimate both sleep and circadian parameters. Overall neuropsychological performance in patients was poor on tasks relating to mental flexibility and visual memory. Two hierarchical cluster analyses identified three distinct patient groups based on sleep variables and three based on circadian variables. Sleep clusters included a 'long sleep' cluster, a 'disrupted sleep' cluster, and a 'delayed and disrupted sleep' cluster. Circadian clusters included a 'strong circadian' cluster, a 'weak circadian' cluster, and a 'delayed circadian' cluster. Medication use differed between clusters. The 'long sleep' cluster displayed significantly worse visual memory performance compared to the 'disrupted sleep' cluster. No other cognitive functions differed between clusters. These results highlight the heterogeneity of sleep and circadian profiles in young people with affective disorders, and provide preliminary evidence in support of a relationship between sleep and visual memory, which may be mediated by use of antipsychotic medication. These findings have implications for the personalisation of treatments and improvement of functioning in

  5. The Relationship between Sleep-Wake Cycle and Cognitive Functioning in Young People with Affective Disorders

    PubMed Central

    Carpenter, Joanne S.; Robillard, Rébecca; Lee, Rico S. C.; Hermens, Daniel F.; Naismith, Sharon L.; White, Django; Whitwell, Bradley; Scott, Elizabeth M.; Hickie, Ian B.

    2015-01-01

    Although early-stage affective disorders are associated with both cognitive dysfunction and sleep-wake disruptions, relationships between these factors have not been specifically examined in young adults. Sleep and circadian rhythm disturbances in those with affective disorders are considerably heterogeneous, and may not relate to cognitive dysfunction in a simple linear fashion. This study aimed to characterise profiles of sleep and circadian disturbance in young people with affective disorders and examine associations between these profiles and cognitive performance. Actigraphy monitoring was completed in 152 young people (16–30 years; 66% female) with primary diagnoses of affective disorders, and 69 healthy controls (18–30 years; 57% female). Patients also underwent detailed neuropsychological assessment. Actigraphy data were processed to estimate both sleep and circadian parameters. Overall neuropsychological performance in patients was poor on tasks relating to mental flexibility and visual memory. Two hierarchical cluster analyses identified three distinct patient groups based on sleep variables and three based on circadian variables. Sleep clusters included a ‘long sleep’ cluster, a ‘disrupted sleep’ cluster, and a ‘delayed and disrupted sleep’ cluster. Circadian clusters included a ‘strong circadian’ cluster, a ‘weak circadian’ cluster, and a ‘delayed circadian’ cluster. Medication use differed between clusters. The ‘long sleep’ cluster displayed significantly worse visual memory performance compared to the ‘disrupted sleep’ cluster. No other cognitive functions differed between clusters. These results highlight the heterogeneity of sleep and circadian profiles in young people with affective disorders, and provide preliminary evidence in support of a relationship between sleep and visual memory, which may be mediated by use of antipsychotic medication. These findings have implications for the personalisation of treatments

  6. Asymmetrical Fc Engineering Greatly Enhances Antibody-dependent Cellular Cytotoxicity (ADCC) Effector Function and Stability of the Modified Antibodies*

    PubMed Central

    Liu, Zhi; Gunasekaran, Kannan; Wang, Wei; Razinkov, Vladimir; Sekirov, Laura; Leng, Esther; Sweet, Heather; Foltz, Ian; Howard, Monique; Rousseau, Anne-Marie; Kozlosky, Carl; Fanslow, William; Yan, Wei

    2014-01-01

    Antibody-dependent cellular cytotoxicity (ADCC) is mediated through the engagement of the Fc segment of antibodies with Fcγ receptors (FcγRs) on immune cells upon binding of tumor or viral antigen. The co-crystal structure of FcγRIII in complex with Fc revealed that Fc binds to FcγRIII asymmetrically with two Fc chains contacting separate regions of the FcγRIII by utilizing different residues. To fully explore this asymmetrical nature of the Fc-FcγR interaction, we screened more than 9,000 individual clones in Fc heterodimer format in which different mutations were introduced at the same position of two Fc chains using a high throughput competition AlphaLISA® assay. To this end, we have identified a panel of novel Fc variants with significant binding improvement to FcγRIIIA (both Phe-158 and Val-158 allotypes), increased ADCC activity in vitro, and strong tumor growth inhibition in mice xenograft human tumor models. Compared with previously identified Fc variants in conventional IgG format, Fc heterodimers with asymmetrical mutations can achieve similar or superior potency in ADCC-mediated tumor cell killing and demonstrate improved stability in the CH2 domain. Fc heterodimers also allow more selectivity toward activating FcγRIIA than inhibitory FcγRIIB. Afucosylation of Fc variants further increases the affinity of Fc to FcγRIIIA, leading to much higher ADCC activity. The discovery of these Fc variants will potentially open up new opportunities of building the next generation of therapeutic antibodies with enhanced ADCC effector function for the treatment of cancers and infectious diseases. PMID:24311787

  7. Amygdala Perfusion Is Predicted by Its Functional Connectivity with the Ventromedial Prefrontal Cortex and Negative Affect

    PubMed Central

    Coombs III, Garth; Loggia, Marco L.; Greve, Douglas N.; Holt, Daphne J.

    2014-01-01

    Background Previous studies have shown that the activity of the amygdala is elevated in people experiencing clinical and subclinical levels of anxiety and depression (negative affect). It has been proposed that a reduction in inhibitory input to the amygdala from the prefrontal cortex and resultant over-activity of the amygdala underlies this association. Prior studies have found relationships between negative affect and 1) amygdala over-activity and 2) reduced amygdala-prefrontal connectivity. However, it is not known whether elevated amygdala activity is associated with decreased amygdala-prefrontal connectivity during negative affect states. Methods Here we used resting-state arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) in combination to test this model, measuring the activity (regional cerebral blood flow, rCBF) and functional connectivity (correlated fluctuations in the BOLD signal) of one subregion of the amygdala with strong connections with the prefrontal cortex, the basolateral nucleus (BLA), and subsyndromal anxiety levels in 38 healthy subjects. Results BLA rCBF was strongly correlated with anxiety levels. Moreover, both BLA rCBF and anxiety were inversely correlated with the strength of the functional coupling of the BLA with the caudal ventromedial prefrontal cortex. Lastly, BLA perfusion was found to be a mediator of the relationship between BLA-prefrontal connectivity and anxiety. Conclusions These results show that both perfusion of the BLA and a measure of its functional coupling with the prefrontal cortex directly index anxiety levels in healthy subjects, and that low BLA-prefrontal connectivity may lead to increased BLA activity and resulting anxiety. Thus, these data provide key evidence for an often-cited circuitry model of negative affect, using a novel, multi-modal imaging approach. PMID:24816735

  8. DISC1 gene and affective psychopathology: a combined structural and functional MRI study.

    PubMed

    Opmeer, Esther M; van Tol, Marie-José; Kortekaas, Rudie; van der Wee, Nic J A; Woudstra, Saskia; van Buchem, Mark A; Penninx, Brenda W; Veltman, Dick J; Aleman, André

    2015-02-01

    The gene Disrupted-In-Schizophrenia-1 (DISC1) has been indicated as a determinant of psychopathology, including affective disorders, and shown to influence prefrontal cortex (PFC) and hippocampus functioning, regions of major interest for affective disorders. We aimed to investigate whether DISC1 differentially modulates brain function during executive and memory processing, and morphology in regions relevant for depression and anxiety disorders (affective disorders). 128 participants, with (n = 103) and without (controls; n = 25) affective disorders underwent genotyping for Ser704Cys (with Cys-allele considered as risk-allele) and structural and functional (f) Magnetic Resonance Imaging (MRI) during visuospatial planning and emotional episodic memory tasks. For both voxel-based morphometry and fMRI analyses, we investigated the effect of genotype in controls and explored genotypeXdiagnosis interactions. Results are reported at p < 0.05 FWE small volume corrected. In controls, Cys-carriers showed smaller bilateral (para)hippocampal volumes compared with Ser-homozygotes, and lower activation in the anterior cingulate cortex (ACC) and dorsolateral PFC during visuospatial planning. In anxiety patients, Cys-carriers showed larger (para)hippocampal volumes and more ACC activation during visuospatial planning. In depressive patients, no effect of genotype was observed and overall, no effect of genotype on episodic memory processing was detected. We demonstrated that Ser704Cys-genotype influences (para)hippocampal structure and functioning the dorsal PFC during executive planning, most prominently in unaffected controls. Results suggest that presence of psychopathology moderates Ser704Cys effects. PMID:25533973

  9. Increase in cellular triacylglycerol content and emergence of large ER-associated lipid droplets in the absence of CDP-DG synthase function

    PubMed Central

    He, Yue; Yam, Candice; Pomraning, Kyle; Chin, Jacqueline S. R.; Yew, Joanne Y.; Freitag, Michael; Oliferenko, Snezhana

    2014-01-01

    Excess fatty acids and sterols are stored as triacylglycerols and sterol esters in specialized cellular organelles, called lipid droplets. Understanding what determines the cellular amount of neutral lipids and their packaging into lipid droplets is of fundamental and applied interest. Using two species of fission yeast, we show that cycling cells deficient in the function of the ER-resident CDP-DG synthase Cds1 exhibit markedly increased triacylglycerol content and assemble large lipid droplets closely associated with the ER membranes. We demonstrate that these unusual structures recruit the triacylglycerol synthesis machinery and grow by expansion rather than by fusion. Our results suggest that interfering with the CDP-DG route of phosphatidic acid utilization rewires cellular metabolism to adopt a triacylglycerol-rich lifestyle reliant on the Kennedy pathway. PMID:25318672

  10. Increase in cellular triacylglycerol content and emergence of large ER-associated lipid droplets in the absence of CDP-DG synthase function.

    PubMed

    He, Yue; Yam, Candice; Pomraning, Kyle; Chin, Jacqueline S R; Yew, Joanne Y; Freitag, Michael; Oliferenko, Snezhana

    2014-12-15

    Excess fatty acids and sterols are stored as triacylglycerols and sterol esters in specialized cellular organelles, called lipid droplets. Understanding what determines the cellular amount of neutral lipids and their packaging into lipid droplets is of fundamental and applied interest. Using two species of fission yeast, we show that cycling cells deficient in the function of the ER-resident CDP-DG synthase Cds1 exhibit markedly increased triacylglycerol content and assemble large lipid droplets closely associated with the ER membranes. We demonstrate that these unusual structures recruit the triacylglycerol synthesis machinery and grow by expansion rather than by fusion. Our results suggest that interfering with the CDP-DG route of phosphatidic acid utilization rewires cellular metabolism to adopt a triacylglycerol-rich lifestyle reliant on the Kennedy pathway. PMID:25318672

  11. Affective Response to a Loved One's Pain: Insula Activity as a Function of Individual Differences

    PubMed Central

    Mazzola, Viridiana; Latorre, Valeria; Petito, Annamaria; Gentili, Nicoletta; Fazio, Leonardo; Popolizio, Teresa; Blasi, Giuseppe; Arciero, Giampiero; Bondolfi, Guido

    2010-01-01

    Individual variability in emotion processing may be associated with genetic variation as well as with psychological predispositions such as dispositional affect styles. Our previous fMRI study demonstrated that amygdala reactivity was independently predicted by affective-cognitive styles (phobic prone or eating disorders prone) and genotype of the serotonin transporter in a discrimination task of fearful facial expressions. Since the insula is associated with the subjective evaluation of bodily states and is involved in human feelings, we explored whether its activity could also vary in function of individual differences. In the present fMRI study, the association between dispositional affects and insula reactivity has been examined in two groups of healthy participants categorized according to affective-cognitive styles (phobic prone or eating disorders prone). Images of the faces of partners and strangers, in both painful and neutral situations, were used as visual stimuli. Interaction analyses indicate significantly different activations in the two groups in reaction to a loved one's pain: the phobic prone group exhibited greater activation in the left posterior insula. These results demonstrate that affective-cognitive style is associated with insula activity in pain empathy processing, suggesting a greater involvement of the insula in feelings for a certain cohort of people. In the mapping of individual differences, these results shed new light on variability in neural networks of emotion. PMID:21179564

  12. Nicotine withdrawal modulates frontal brain function during an affective Stroop task

    PubMed Central

    Modlin, Leslie; Wang, Lihong; Kozink, Rachel V.; McClernon, F. Joseph

    2013-01-01

    Background Among nicotine-dependent smokers, smoking abstinence disrupts multiple cognitive and affective processes including conflict resolution and emotional information processing (EIP). However, the neurobiological basis of abstinence effects on resolving emotional interference on cognition remains largely uncharacterized. In this study, functional magnetic resonance imaging (fMRI) was used to investigate smoking abstinence effects on emotion–cognition interactions. Methods Smokers (n=17) underwent fMRI while performing an affective Stroop task (aST) over two sessions: once following 24-h abstinence and once following smoking as usual. The aST includes trials that serially present incongruent or congruent numerical grids bracketed by neutral or negative emotional distractors and view-only emotional image trials. Statistical analyses were conducted using a statistical threshold of p<0.05 cluster corrected. Results Smoking abstinence increased Stroop blood-oxygenation-level-dependent response in the right middle frontal and rostral anterior cingulate gyri. Moreover, withdrawal-induced negative affect was associated with less activation in frontoparietal regions during negative emotional information processing; whereas, during Stroop trials, negative affect predicted greater activation in frontal regions during negative, but not neutral emotional distractor trials. Conclusion Hyperactivation in the frontal executive control network during smoking abstinence may represent a need to recruit additional executive resources to meet task demands. Moreover, abstinence-induced negative affect may disrupt cognitive control neural circuitry during EIP and place additional demands on frontal executive neural resources during cognitive demands when presented with emotionally distracting stimuli. PMID:21989805

  13. Genes Encoding Cher-TPR Fusion Proteins Are Predominantly Found in Gene Clusters Encoding Chemosensory Pathways with Alternative Cellular Functions

    PubMed Central

    Rico-Jiménez, Miriam; Alfonso, Carlos; Krell, Tino

    2012-01-01

    Chemosensory pathways correspond to major signal transduction mechanisms and can be classified into the functional families flagellum-mediated taxis, type four pili-mediated taxis or pathways with alternative cellular functions (ACF). CheR methyltransferases are core enzymes in all of these families. CheR proteins fused to tetratricopeptide repeat (TPR) domains have been reported and we present an analysis of this uncharacterized family. We show that CheR-TPRs are widely distributed in GRAM-negative but almost absent from GRAM-positive bacteria. Most strains contain a single CheR-TPR and its abundance does not correlate with the number of chemoreceptors. The TPR domain fused to CheR is comparatively short and frequently composed of 2 repeats. The majority of CheR-TPR genes were found in gene clusters that harbor multidomain response regulators in which the REC domain is fused to different output domains like HK, GGDEF, EAL, HPT, AAA, PAS, GAF, additional REC, HTH, phosphatase or combinations thereof. The response regulator architectures coincide with those reported for the ACF family of pathways. Since the presence of multidomain response regulators is a distinctive feature of this pathway family, we conclude that CheR-TPR proteins form part of ACF type pathways. The diversity of response regulator output domains suggests that the ACF pathways form a superfamily which regroups many different regulatory mechanisms, in which all CheR-TPR proteins appear to participate. In the second part we characterize WspC of Pseudomonas putida, a representative example of CheR-TPR. The affinities of WspC-Pp for S-adenosylmethionine and S-adenosylhomocysteine were comparable to those of prototypal CheR, indicating that WspC-Pp activity is in analogy to prototypal CheRs controlled by product feed-back inhibition. The removal of the TPR domain did not impact significantly on the binding constants and consequently not on the product feed-back inhibition. WspC-Pp was found to be

  14. Functional ultrastructure of eggs and cellular organization of hexacanths of the cyclophyllidean cestode Thysanotaenia congolensis: a phylogenetic implication of obtained results.

    PubMed

    Świderski, Zdzisław; Miquel, Jordi; Conn, David Bruce

    2016-03-01

    The functional ultrastructure of eggs and cellular organization of hexacanths from gravid proglottids of Thysanotaenia congolensis, from black rats from Cape Verde, were examined by transmission electron microscopy. Mature eggs with fully formed hexacanths are grouped within parenchymatous capsules of gravid proglottids. Oncospheral envelopes surrounding mature hexacanths are reduced to a very thin membranous embryophore as their protective function is taken over by the parenchymatous capsules originating from the medullary parenchyma of immature proglottids and composed of three layers. Six major cell types are present: a bi-nucleate medullary centre; a six-nucleate U-shaped penetration gland; a second type of penetration gland; two neurosecretory-type nerve cells; about 30 somatic cells; and about 12 germinative cells. Present results on the functional ultrastructure of eggs and cellular organization of hexacanths support the phylogenetic distinction between T. congolensis and cestodes of the subfamily Anoplocephalinae. PMID:26689933

  15. Estradiol affects liver mitochondrial function in ovariectomized and tamoxifen-treated ovariectomized female rats

    SciTech Connect

    Moreira, Paula I.; Custodio, Jose B.A.; Nunes, Elsa; Moreno, Antonio; Seica, Raquel; Oliveira, Catarina R.; Santos, Maria S. . E-mail: mssantos@ci.uc.pt

    2007-05-15

    Given the tremendous importance of mitochondria to basic cellular functions as well as the critical role of mitochondrial impairment in a vast number of disorders, a compelling question is whether 17{beta}-estradiol (E2) modulates mitochondrial function. To answer this question we exposed isolated liver mitochondria to E2. Three groups of rat females were used: control, ovariectomized and ovariectomized treated with tamoxifen. Tamoxifen has antiestrogenic effects in the breast tissue and is the standard endocrine treatment for women with breast cancer. However, under certain circumstances and in certain tissues, tamoxifen can also exert estrogenic agonist properties. We observed that at basal conditions, ovariectomy and tamoxifen treatment do not induce any statistical alteration in oxidative phosphorylation system and respiratory chain parameters. Furthermore, tamoxifen treatment increases the capacity of mitochondria to accumulate Ca{sup 2+} delaying the opening of the permeability transition pore. The presence of 25 {mu}M E2 impairs respiration and oxidative phosphorylation system these effects being similar in all groups of animals studied. Curiously, E2 protects against lipid peroxidation and increases the production of H{sub 2}O{sub 2} in energized mitochondria of control females. Our results indicate that E2 has in general deleterious effects that lead to mitochondrial impairment. Since mitochondrial dysfunction is a triggering event of cell degeneration and death, the use of exogenous E2 must be carefully considered.

  16. Psychosocial Functioning in Depressive Patients: A Comparative Study between Major Depressive Disorder and Bipolar Affective Disorder

    PubMed Central

    Mittal, Pankaj Kumar; Swami, Mukesh Kumar

    2014-01-01

    Introduction. Major depressive disorder (MDD) and bipolar affective disorder (BAD) are among the leading causes of disability. These are often associated with widespread impairments in all domains of functioning including relational, occupational, and social. The main aim of the study was to examine and compare nature and extent of psychosocial impairment of patients with MDD and BAD during depressive phase. Methodology. 96 patients (48 in MDD group and 48 in BAD group) were included in the study. Patients were recruited in depressive phase (moderate to severe depression). Patients having age outside 18–45 years, psychotic symptoms, mental retardation, and current comorbid medical or axis-1 psychiatric disorder were excluded. Psychosocial functioning was assessed using Range of Impaired Functioning Tool (LIFE-RIFT). Results. Domains of work, interpersonal relationship, life satisfaction, and recreation were all affected in both groups, but the groups showed significant difference in global psychosocial functioning score only (P = 0.031) with BAD group showing more severe impairment. Conclusion. Bipolar depression causes higher global psychosocial impairment than unipolar depression. PMID:24744917

  17. Cellular Stress Responses and Monitored Cellular Activities.

    PubMed

    Sawa, Teiji; Naito, Yoshifumi; Kato, Hideya; Amaya, Fumimasa

    2016-08-01

    To survive, organisms require mechanisms that enable them to sense changes in the outside environment, introduce necessary responses, and resist unfavorable distortion. Consequently, through evolutionary adaptation, cells have become equipped with the apparatus required to monitor their fundamental intracellular processes and the mechanisms needed to try to offset malfunction without receiving any direct signals from the outside environment. It has been shown recently that eukaryotic cells are equipped with a special mechanism that monitors their fundamental cellular functions and that some pathogenic proteobacteria can override this monitoring mechanism to cause harm. The monitored cellular activities involved in the stressed intracellular response have been researched extensively in Caenorhabditis elegans, where discovery of an association between key mitochondrial activities and innate immune responses was named "cellular associated detoxification and defenses (cSADD)." This cellular surveillance pathway (cSADD) oversees core cellular activities such as mitochondrial respiration and protein transport into mitochondria, detects xenobiotics and invading pathogens, and activates the endocrine pathways controlling behavior, detoxification, and immunity. The cSADD pathway is probably associated with cellular responses to stress in human inflammatory diseases. In the critical care field, the pathogenesis of lethal inflammatory syndromes (e.g., respiratory distress syndromes and sepsis) involves the disturbance of mitochondrial respiration leading to cell death. Up-to-date knowledge about monitored cellular activities and cSADD, especially focusing on mitochondrial involvement, can probably help fill a knowledge gap regarding the pathogenesis of lethal inflammatory syndromes in the critical care field. PMID:26954943

  18. The protective function of personal growth initiative among a genocide-affected population in Rwanda.

    PubMed

    Blackie, Laura E R; Jayawickreme, Eranda; Forgeard, Marie J C; Jayawickreme, Nuwan

    2015-07-01

    The aim of the current study was to investigate the extent to which individual differences in personal growth initiative (PGI) were associated with lower reports of functional impairment of daily activities among a genocide-affected population in Rwanda. PGI measures an individual's motivation to develop as a person and the extent to which he or she is active in setting goals that work toward achieving self-improvement. We found that PGI was negatively associated with functional impairment when controlling for depression, posttraumatic stress disorder, and other demographic factors. Our results suggest that PGI may constitute an important mindset for facilitating adaptive functioning in the aftermath of adversity and in the midst of psychological distress, and as such they might have practical applications for the development of intervention programs. PMID:26147518

  19. Developing fragility functions for the areas affected by the 2009 Samoa earthquake and tsunami

    NASA Astrophysics Data System (ADS)

    Gokon, H.; Koshimura, S.; Imai, K.; Matsuoka, M.; Namegaya, Y.; Nishimura, Y.

    2014-12-01

    Fragility functions in terms of flow depth, flow velocity and hydrodynamic force are developed to evaluate structural vulnerability in the areas affected by the 2009 Samoa earthquake and tsunami. First, numerical simulations of tsunami propagation and inundation are conducted to reproduce the features of tsunami inundation. To validate the results, flow depths measured in field surveys and waveforms measured by Deep-ocean Assessment and Reporting of Tsunamis (DART) gauges are utilized. Next, building damage is investigated by visually interpreting changes between pre- and post-tsunami high-resolution satellite images. Finally, the data related to tsunami features and building damage are integrated using Geographic Information System (GIS), and tsunami fragility functions are developed based on the statistical analyses. From the developed fragility functions, we quantitatively understood the vulnerability of a coastal region in American Samoa characterized by steep terrains and ria coasts.

  20. Intracellular Localization and Cellular Factors Interaction of HTLV-1 and HTLV-2 Tax Proteins: Similarities and Functional Differences

    PubMed Central

    Bertazzoni, Umberto; Turci, Marco; Avesani, Francesca; Di Gennaro, Gianfranco; Bidoia, Carlo; Romanelli, Maria Grazia

    2011-01-01

    Human T-lymphotropic viruses type 1 (HTLV-1) and type 2 (HTLV-2) present very similar genomic structures but HTLV-1 is more pathogenic than HTLV-2. Is this difference due to their transactivating Tax proteins, Tax-1 and Tax-2, which are responsible for viral and cellular gene activation? Do Tax-1 and Tax-2 differ in their cellular localization and in their interaction pattern with cellular factors? In this review, we summarize Tax-1 and Tax-2 structural and phenotypic properties, their interaction with factors involved in signal transduction and their localization-related behavior within the cell. Special attention will be given to the distinctions between Tax-1 and Tax-2 that likely play an important role in their transactivation activity. PMID:21994745

  1. Ex vivo assessment of cellular immune function - applications in patient care and clinical studies.

    PubMed

    Lindemann, M

    2014-11-01

    Cellular ex vivo assays have a broad range of applications in patient care and clinical studies, especially when they are standardized and highly sensitive. As compared to analyses by molecular genetics such as the single nucleotide polymorphism (SNP) testing, they are usually more global. These assays partly mimic the in vivo situation, relying on a complex interaction of various immune cells. For example, they can be used to determine modulation of alloresponses by treatment or underlying disease, diagnose and quantify primary and secondary cellular immunodeficiency, follow-up vaccination responses, measure adoptive transfer of virus-specific immunity via hematopoietic stem cell or liver transplantation, assess allergy, antimicrobial immunity and also rare effector/memory cells directed against tumor antigens. This review will first shortly describe various cellular in vitro methods and then present applications, summarizing some own studies performed within the last 18 years. PMID:25329632

  2. Plant diversity and functional groups affect Si and Ca pools in aboveground biomass of grassland systems.

    PubMed

    Schaller, Jörg; Roscher, Christiane; Hillebrand, Helmut; Weigelt, Alexandra; Oelmann, Yvonne; Wilcke, Wolfgang; Ebeling, Anne; Weisser, Wolfgang W

    2016-09-01

    Plant diversity is an important driver of nitrogen and phosphorus stocks in aboveground plant biomass of grassland ecosystems, but plant diversity effects on other elements also important for plant growth are less understood. We tested whether plant species richness, functional group richness or the presence/absence of particular plant functional groups influences the Si and Ca concentrations (mmol g(-1)) and stocks (mmol m(-2)) in aboveground plant biomass in a large grassland biodiversity experiment (Jena Experiment). In the experiment including 60 temperate grassland species, plant diversity was manipulated as sown species richness (1, 2, 4, 8, 16) and richness and identity of plant functional groups (1-4; grasses, small herbs, tall herbs, legumes). We found positive species richness effects on Si as well as Ca stocks that were attributable to increased biomass production. The presence of particular functional groups was the most important factor explaining variation in aboveground Si and Ca stocks (mmol m(-2)). Grass presence increased the Si stocks by 140 % and legume presence increased the Ca stock by 230 %. Both the presence of specific plant functional groups and species diversity altered Si and Ca stocks, whereas Si and Ca concentration were affected mostly by the presence of specific plant functional groups. However, we found a negative effect of species diversity on Si and Ca accumulation, by calculating the deviation between mixtures and mixture biomass proportions, but in monoculture concentrations. These changes may in turn affect ecosystem processes such as plant litter decomposition and nutrient cycling in grasslands. PMID:27164912

  3. A newly recognized autosomal recessive syndrome affecting neurologic function and vision.

    PubMed

    Salih, Mustafa A; Tzschach, Andreas; Oystreck, Darren T; Hassan, Hamdy H; AlDrees, Abdulmajeed; Elmalik, Salah A; El Khashab, Heba Y; Wienker, Thomas F; Abu-Amero, Khaled K; Bosley, Thomas M

    2013-06-01

    Genetic factors represent an important etiologic group in the causation of intellectual disability. We describe a Saudi Arabian family with closley related parents in which four of six children were affected by a congenital cognitive disturbance. The four individuals (aged 18, 16, 13, and 2 years when last examined) had motor and cognitive delay with seizures in early childhood, and three of the four (sparing only the youngest child) had progressive, severe cognitive decline with spasticity. Two affected children had ocular malformations, and the three older children had progressive visual loss. The youngest had normal globes with good functional vision when last examined but exhibited the oculodigital sign, which may signify a subclinical visual deficit. A potentially deleterious nucleotide change (c.1A>G; p.Met1Val) in the C12orf57 gene was homozygous in all affected individuals, heterozygous in the parents, and absent in an unaffected sibling and >350 normal individuals. This gene has no known function. This family manifests a autosomal recessive syndrome with some phenotypic variability that includes abnormal development of brain and eyes, delayed cognitive and motor milestones, seizures, and a severe cognitive and visual decline that is associated with a homozygous variant in a newly identified gene. PMID:23633300

  4. Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis.

    PubMed

    Dang, Wei; Zhang, Wen; Du, Wei-Guo

    2015-01-01

    Identifying how developmental temperature affects the immune system is critical for understanding how ectothermic animals defend against pathogens and their fitness in the changing world. However, reptiles have received little attention regarding this issue. We incubated eggs at three ecologically relevant temperatures to determine how incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis. When exposed to bacterial infections, hatchlings from 24 °C had lower cumulative mortalities (55%, therefore, higher immunocompetence) than those from 28 °C (85%) or 32 °C (100%). Consistent with higher immunocompetence, hatchlings from low incubation temperature had higher IgM, IgD, and CD3γ expressions than their counterparts from the other two higher incubation temperatures. Conversely, the activity of immunity-related enzymes did not match the among-temperature difference in immune function. Specifically, enzyme activity was higher at intermediate temperatures (alkaline phosphatase) or was not affected by incubation temperature (acid phosphatase, lysozyme). Our study is the first to provide unequivocal evidence (at the molecular and organismal level) about the significant effect of incubation temperature on offspring immunity in reptiles. Our results also indicate that the reduced immunity induced by high developmental temperatures might increase the vulnerability of reptiles to the outbreak of diseases under global warming scenarios. PMID:26028216

  5. Incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis

    PubMed Central

    Dang, Wei; Zhang, Wen; Du, Wei-Guo

    2015-01-01

    Identifying how developmental temperature affects the immune system is critical for understanding how ectothermic animals defend against pathogens and their fitness in the changing world. However, reptiles have received little attention regarding this issue. We incubated eggs at three ecologically relevant temperatures to determine how incubation temperature affects the immune function of hatchling soft-shelled turtles, Pelodiscus sinensis. When exposed to bacterial infections, hatchlings from 24 °C had lower cumulative mortalities (55%, therefore, higher immunocompetence) than those from 28 °C (85%) or 32 °C (100%). Consistent with higher immunocompetence, hatchlings from low incubation temperature had higher IgM, IgD, and CD3γ expressions than their counterparts from the other two higher incubation temperatures. Conversely, the activity of immunity-related enzymes did not match the among-temperature difference in immune function. Specifically, enzyme activity was higher at intermediate temperatures (alkaline phosphatase) or was not affected by incubation temperature (acid phosphatase, lysozyme). Our study is the first to provide unequivocal evidence (at the molecular and organismal level) about the significant effect of incubation temperature on offspring immunity in reptiles. Our results also indicate that the reduced immunity induced by high developmental temperatures might increase the vulnerability of reptiles to the outbreak of diseases under global warming scenarios. PMID:26028216

  6. Phthalate esters affect maturation and function of primate testis tissue ectopically grafted in mice

    PubMed Central

    Rodriguez-Sosa, Jose R; Bondareva, Alla; Tang, Lin; Avelar, Gleide F.; Coyle, Krysta M.; Modelski, Mark; Alpaugh, Whitney; Conley, Alan; Wynne-Edwards, Katherine; França, Luiz R; Meyers, Stuart; Dobrinski, Ina

    2014-01-01

    Di-n-Butyl (DBP) and Di-(2-EthylHexyl) (DEHP) phthalates can leach from daily-use products resulting in environmental exposure. In male rodents, phthalate exposure results in reproductive effects. To evaluate effects on the immature primate testis, testis fragments from 6-month-old rhesus macaques were grafted subcutaneously to immune-deficient mice, which were exposed to 0, 10, or 500 mg/kg of DBP or DEHP for 14 weeks or 28 weeks (DBP only). DBP exposure reduced the expression of key steroidogenic genes, indicating that Leydig cell function was compromised. Exposure to 500 mg/kg impaired tubule formation and germ cell differentiation and reduced numbers of spermatogonia. Exposure to 10 mg/kg did not affect development, but reduced Sertoli cell number and resulted in increased expression of inhibin B. Exposure to DEHP for 14 week also affected steroidogenic genes expression. Therefore, long-term exposure to phthalate esters affected development and function of the primate testis in a time and dosage dependent manner. PMID:25450860

  7. Elementary neurocognitive function, facial affect recognition and social-skills in schizophrenia.

    PubMed

    Meyer, Melissa B; Kurtz, Matthew M

    2009-05-01

    Social-skill deficits are pervasive in schizophrenia and negatively impact many key aspects of functioning. Prior studies have found that measures of elementary neurocognition and social cognition are related to social-skills. In the present study we selected a range of neurocognitive measures and examined their relationship with identification of happy and sad faces and performance-based social-skills. Fifty-three patients with schizophrenia or schizoaffective disorder participated. Results revealed that: 1) visual vigilance, problem-solving and affect recognition were related to social-skill; 2) links between problem-solving and social-skill, but not visual vigilance and social-skill, remained significant when estimates of verbal intelligence were controlled; 3) affect recognition deficits explained unique variance in social-skill after neurocognitive variables were controlled; and 4) affect recognition deficits partially mediated the relationship of visual vigilance and social-skill. These results support the conclusion that facial affect recognition deficits are a crucial domain of impairment in schizophrenia that both contribute unique variance to social-skill deficits and may also mediate the relationship between some aspects of neurocognition and social-skill. These findings may help guide the development and refinement of cognitive and social-cognitive remediation methods for social-skill impairment. PMID:19328653

  8. Functional Connectivity of Pain-Mediated Affect Regulation in Borderline Personality Disorder

    PubMed Central

    Niedtfeld, Inga; Kirsch, Peter; Schulze, Lars; Herpertz, Sabine C.; Bohus, Martin; Schmahl, Christian

    2012-01-01

    Affective instability and self-injurious behavior are important features of Borderline Personality Disorder. Whereas affective instability may be caused by a pattern of limbic hyperreactivity paired with dysfunctional prefrontal regulation mechanisms, painful stimulation was found to reduce affective arousal at the neural level, possibly underlying the soothing effect of pain in BPD. We used psychophysiological interactions to analyze functional connectivity of (para-) limbic brain structures (i.e. amygdala, insula, anterior cingulate cortex) in Borderline Personality Disorder in response to painful stimulation. Therefore, we re-analyzed a dataset from 20 patients with Borderline Personality Disorder and 23 healthy controls who took part in an fMRI-task inducing negative (versus neutral) affect and subsequently applying heat pain (versus warmth perception). Results suggest an enhanced negative coupling between limbic as well as paralimbic regions and prefrontal regions, specifically with the medial and dorsolateral prefrontal cortex, when patients experienced pain in addition to emotional arousing pictures. When neutral pictures were combined with painful heat sensation, we found positive connectivity in Borderline Personality Disorder between (para-)limbic brain areas and parts of the basal ganglia (lentiform nucleus, putamen), as well areas involved in self-referential processing (precuneus and posterior cingulate). We found further evidence for alterations in the emotion regulation process in Borderline Personality Disorder, in the way that pain improves the inhibition of limbic activity by prefrontal areas. This study provides new insights in pain processing in BPD, including enhanced coupling of limbic structures and basal ganglia. PMID:22428013

  9. Interleukin-6 (IL-6) and IL-17 Synergistically Promote Viral Persistence by Inhibiting Cellular Apoptosis and Cytotoxic T Cell Function

    PubMed Central

    Hou, Wanqiu; Jin, Young-Hee; Kang, Hyun Seok

    2014-01-01

    ABSTRACT Interleukin-6 (IL-6) plays an important role in the development and progression of inflammatory responses, autoimmune diseases, and cancers. Many viral infections, including Theiler's murine encephalomyelitis virus (TMEV), result in the vigorous production of IL-6. However, the role of IL-6 in the development of virus-induced inflammatory responses is unclear. The infection of susceptible mice with TMEV induces the development of chronic demyelinating disease, which is considered a relevant infectious model for multiple sclerosis. In this study, we demonstrate that resistant C57BL/6 mice carrying an IL-6 transgene (IL-6 Tg) develop a TMEV-induced demyelinating disease accompanied by an increase in viral persistence and an elevated Th17 cell response in the central nervous system. Either IL-6 or IL-17 induced the expression of Bcl-2 and Bcl-xL at a high concentration. The upregulated expression of prosurvival molecules in turn inhibited target cell destruction by virus-specific CD8+ T cells. More interestingly, IL-6 and IL-17 synergistically promoted the expression of these prosurvival molecules, preventing cellular apoptosis at a much lower (<5-fold) concentration. The signals involved in the synergy appear to include the activation of both STAT3 and NF-κB via distinct cytokine-dependent pathways. Thus, the excessive IL-6 promotes the generation of Th17 cells, and the resulting IL-6 and IL-17 synergistically promote viral persistence by protecting virus-infected cells from apoptosis and CD8+ T cell-mediated target destruction. These results suggest that blocking both IL-6 and IL-17 functions are important considerations for therapies of chronic viral diseases, autoimmune diseases, and cancers. IMPORTANCE This study indicates that an excessive level of IL-6 cytokine produced following viral infection promotes the development of IL-17-producing pathogenic helper T cells. We demonstrate here for the first time that IL-6 together with IL-17 synergistically

  10. Cellular function and pathological role of ATP13A2 and related P-type transport ATPases in Parkinson's disease and other neurological disorders

    PubMed Central

    van Veen, Sarah; Sørensen, Danny M.; Holemans, Tine; Holen, Henrik W.; Palmgren, Michael G.; Vangheluwe, Peter

    2014-01-01

    Mutations in ATP13A2 lead to Kufor-Rakeb syndrome, a parkinsonism with dementia. ATP13A2 belongs to the P-type transport ATPases, a large family of primary active transporters that exert vital cellular functions. However, the cellular function and transported substrate of ATP13A2 remain unknown. To discuss the role of ATP13A2 in neurodegeneration, we first provide a short description of the architecture and transport mechanism of P-type transport ATPases. Then, we briefly highlight key P-type ATPases involved in neuronal disorders such as the copper transporters ATP7A (Menkes disease), ATP7B (Wilson disease), the Na+/K+-ATPases ATP1A2 (familial hemiplegic migraine) and ATP1A3 (rapid-onset dystonia parkinsonism). Finally, we review the recent literature of ATP13A2 and discuss ATP13A2's putative cellular function in the light of what is known concerning the functions of other, better-studied P-type ATPases. We critically review the available data concerning the role of ATP13A2 in heavy metal transport and propose a possible alternative hypothesis that ATP13A2 might be a flippase. As a flippase, ATP13A2 may transport an organic molecule, such as a lipid or a peptide, from one membrane leaflet to the other. A flippase might control local lipid dynamics during vesicle formation and membrane fusion events. PMID:24904274

  11. Molecular Basis and Therapeutic Strategies to Rescue Factor IX Variants That Affect Splicing and Protein Function.

    PubMed

    Tajnik, Mojca; Rogalska, Malgorzata Ewa; Bussani, Erica; Barbon, Elena; Balestra, Dario; Pinotti, Mirko; Pagani, Franco

    2016-05-01

    Mutations that result in amino acid changes can affect both pre-mRNA splicing and protein function. Understanding the combined effect is essential for correct diagnosis and for establishing the most appropriate therapeutic strategy at the molecular level. We have identified a series of disease-causing splicing mutations in coagulation factor IX (FIX) exon 5 that are completely recovered by a modified U1snRNP particle, through an SRSF2-dependent enhancement mechanism. We discovered that synonymous mutations and missense substitutions associated to a partial FIX secretion defect represent targets for this therapy as the resulting spliced-corrected proteins maintains normal FIX coagulant specific activity. Thus, splicing and protein alterations contribute to define at the molecular level the disease-causing effect of a number of exonic mutations in coagulation FIX exon 5. In addition, our results have a significant impact in the development of splicing-switching therapies in particular for mutations that affect both splicing and protein function where increasing the amount of a correctly spliced protein can circumvent the basic functional defects. PMID:27227676

  12. Molecular Basis and Therapeutic Strategies to Rescue Factor IX Variants That Affect Splicing and Protein Function

    PubMed Central

    Bussani, Erica; Barbon, Elena; Pinotti, Mirko; Pagani, Franco

    2016-01-01

    Mutations that result in amino acid changes can affect both pre-mRNA splicing and protein function. Understanding the combined effect is essential for correct diagnosis and for establishing the most appropriate therapeutic strategy at the molecular level. We have identified a series of disease-causing splicing mutations in coagulation factor IX (FIX) exon 5 that are completely recovered by a modified U1snRNP particle, through an SRSF2-dependent enhancement mechanism. We discovered that synonymous mutations and missense substitutions associated to a partial FIX secretion defect represent targets for this therapy as the resulting spliced-corrected proteins maintains normal FIX coagulant specific activity. Thus, splicing and protein alterations contribute to define at the molecular level the disease-causing effect of a number of exonic mutations in coagulation FIX exon 5. In addition, our results have a significant impact in the development of splicing-switching therapies in particular for mutations that affect both splicing and protein function where increasing the amount of a correctly spliced protein can circumvent the basic functional defects. PMID:27227676

  13. Microbial Functional Potential and Community Composition in Permafrost-Affected Soils of the NW Canadian Arctic

    PubMed Central

    Frank-Fahle, Béatrice A.; Yergeau, Étienne; Greer, Charles W.; Lantuit, Hugues; Wagner, Dirk

    2014-01-01

    Permafrost-affected soils are among the most obvious ecosystems in which current microbial controls on organic matter decomposition are changing as a result of global warming. Warmer conditions in polygonal tundra will lead to a deepening of the seasonal active layer, provoking changes in microbial processes and possibly resulting in exacerbated carbon degradation under increasing anoxic conditions. To identify current microbial assemblages in carbon rich, water saturated permafrost environments, four polygonal tundra sites were investigated on Herschel Island and the Yukon Coast, Western Canadian Arctic. Ion Torrent sequencing of bacterial and archaeal 16S rRNA amplicons revealed the presence of all major microbial soil groups and indicated a local, vertical heterogeneity of the polygonal tundra soil community with increasing depth. Microbial diversity was found to be highest in the surface layers, decreasing towards the permafrost table. Quantitative PCR analysis of functional genes involved in carbon and nitrogen-cycling revealed a high functional potential in the surface layers, decreasing with increasing active layer depth. We observed that soil properties driving microbial diversity and functional potential varied in each study site. These results highlight the small-scale heterogeneity of geomorphologically comparable sites, greatly restricting generalizations about the fate of permafrost-affected environments in a warming Arctic. PMID:24416279

  14. Molecular and Cellular Mechanisms Elucidating Neurocognitive Basis of Functional Impairments Associated with Intellectual Disability in Down Syndrome

    ERIC Educational Resources Information Center

    Rachidi, Mohammed; Lopes, Carmela

    2010-01-01

    Down syndrome, the most common genetic cause of intellectual disability, is associated with brain disorders due to chromosome 21 gene overdosage. Molecular and cellular mechanisms involved in the neuromorphological alterations and cognitive impairments are reported herein in a global model. Recent advances in Down syndrome research have lead to…

  15. The Functional Effect of Teacher Positive and Neutral Affect on Task Performance of Students with Significant Disabilities

    ERIC Educational Resources Information Center

    Park, Sungho; Singer, George H. S.; Gibson, Mary

    2005-01-01

    The study uses an alternating treatment design to evaluate the functional effect of teacher's affect on students' task performance. Tradition in special education holds that teachers should engage students using positive and enthusiastic affect for task presentations and praise. To test this assumption, we compared two affective conditions. Three…

  16. Extender components and surfactants affect boar sperm function and membrane behavior during cryopreservation.

    PubMed

    Pettitt, M J; Buhr, M M

    1998-01-01

    To determine how the individual components of extenders affected boar sperm function and membrane structure and to test a new surfactant's cryoprotective ability, boar sperm were cryopreserved in straws in BF5 extender plus or minus egg yolk plus or minus glycerol plus or minus a surfactant (Orvus ES Paste [OEP] or various concentrations of Pluronic F-127). After thawing, sperm function and fluidity of the isolated head plasma membrane (HPM) were determined. Total motility and adenosine triphosphate content (a measure of viability) were superior postthaw in sperm extended in egg yolk plus glycerol (P < 0.05); neither surfactant improved function. Egg yolk plus any other ingredients improved normal acrosome morphology, whereas a combined measure of motility and normal acrosome morphology was better in the presence of 0.33% OEP or 0.1% Pluronic F-127 (P < 0.05 vs. controls). Head plasma membrane was isolated from freshly collected spermatozoa and spermatozoa cryopreserved in the various extenders. Membrane fluidity was monitored with the probes cis-parinaric acid (cPNA), transparinaric acid (tPNA), and 1,6-diphenyl-1 ,3,5-hexatriene (DPH). The cPNA and the DPH monitor the fluidity of gel and liquid-crystalline areas of the membrane, whereas the tPNA preferentially monitors the gel-phase domains of the membrane. Additionally, DPH monitors the hydrophobic core of the bilayer. In the HPM from fresh sperm, the fluidity of each domain changed over time in a manner unique to that domain, and the behavior of the DPH domain varied among boars. The fluidity dynamics of each domain responded uniquely to cryopreservation. The cPNA domain was unaffected, the tPNA domain was altered by four of the eight extenders, and all extenders affected the fluidity of the DPH domain. Membrane structure was significantly correlated with cell function for sperm cryopreserved in extenders that preserved viability and motility. Sperm cryopreserved in egg yolk plus glycerol plus either OEP or 0

  17. Ultra-endurance exercise induces stress and inflammation and affects circulating hematopoietic progenitor cell function.

    PubMed

    Stelzer, I; Kröpfl, J M; Fuchs, R; Pekovits, K; Mangge, H; Raggam, R B; Gruber, H-J; Prüller, F; Hofmann, P; Truschnig-Wilders, M; Obermayer-Pietsch, B; Haushofer, A C; Kessler, H H; Mächler, P

    2015-10-01

    Although amateur sports have become increasingly competitive within recent decades, there are as yet few studies on the possible health risks for athletes. This study aims to determine the impact of ultra-endurance exercise-induced stress on the number and function of circulating hematopoietic progenitor cells (CPCs) and hematological, inflammatory, clinical, metabolic, and stress parameters in moderately trained amateur athletes. Following ultra-endurance exercise, there were significant increases in leukocytes, platelets, interleukin-6, fibrinogen, tissue enzymes, blood lactate, serum cortisol, and matrix metalloproteinase-9. Ultra-endurance exercise did not influence the number of CPCs but resulted in a highly significant decline of CPC functionality after the competition. Furthermore, Epstein-Barr virus was seen to be reactivated in one of seven athletes. The link between exercise-induced stress and decline of CPC functionality is supported by a negative correlation between cortisol and CPC function. We conclude that ultra-endurance exercise induces metabolic stress and an inflammatory response that affects not only mature hematopoietic cells but also the function of the immature hematopoietic stem and progenitor cell fraction, which make up the immune system and provide for regeneration. PMID:25438993

  18. Cure Kinetics of Epoxy Nanocomposites Affected by MWCNTs Functionalization: A Review

    PubMed Central

    Saeb, Mohammad Reza; Bakhshandeh, Ehsan; Khonakdar, Hossein Ali; Mäder, Edith; Scheffler, Christina; Heinrich, Gert

    2013-01-01

    The current paper provides an overview to emphasize the role of functionalization of multiwalled carbon nanotubes (MWCNTs) in manipulating cure kinetics of epoxy nanocomposites, which itself determines ultimate properties of the resulting compound. In this regard, the most commonly used functionalization schemes, that is, carboxylation and amidation, are thoroughly surveyed to highlight the role of functionalized nanotubes in controlling the rate of autocatalytic and vitrification kinetics. The current literature elucidates that the mechanism of curing in epoxy/MWCNTs nanocomposites remains almost unaffected by the functionalization of carbon nanotubes. On the other hand, early stage facilitation of autocatalytic reactions in the presence of MWCNTs bearing amine groups has been addressed by several researchers. When carboxylated nanotubes were used to modify MWCNTs, the rate of such reactions diminished as a consequence of heterogeneous dispersion within the epoxy matrix. At later stages of curing, however, the prolonged vitrification was seen to be dominant. Thus, the type of functional groups covalently located on the surface of MWCNTs directly affects the degree of polymer-nanotube interaction followed by enhancement of curing reaction. Our survey demonstrated that most widespread efforts ever made to represent multifarious surface-treated MWCNTs have not been directed towards preparation of epoxy nanocomposites, but they could result in property synergism. PMID:24348181

  19. Six-Digit CPK and Mildly Affected Renal Function in McArdle Disease

    PubMed Central

    Mcinnes, Andrew D.; DeGroote, Richard J.

    2014-01-01

    A previously healthy, white 12-year-old girl presented with diffuse body aches and poor perfusion. She developed severe respiratory failure and marked rhabdomyolysis and was mechanically ventilated. Although her CPK peaked at 500,000 IU/L, her renal function was mildly affected and her creatinine did not exceed the 0.8 mg/dL. The rhabdomyolysis was gradually resolved following aggressive fluid hydration. The patient did not require dialysis and made a complete recovery. Genetic studies revealed the diagnosis of McArdle disease. PMID:25371840

  20. Functional Profiling Discovers the Dieldrin Organochlorinated Pesticide Affects Leucine Availability in Yeast

    PubMed Central

    Vulpe, Chris D.

    2013-01-01

    Exposure to organochlorinated pesticides such as dieldrin has been linked to Parkinson’s and Alzheimer’s diseases, endocrine disruption, and cancer, but the cellular and molecular mechanisms of toxicity behind these effects remain largely unknown. Here we demonstrate, using a functional genomics approach in the model eukaryote Saccharomyces cerevisiae, that dieldrin alters leucine availability. This model is supported by multiple lines of congruent evidence: (1) mutants defective in amino acid signaling or transport are sensitive to dieldrin, which is reversed by the addition of exogenous leucine; (2) dieldrin sensitivity of wild-type or mutant strains is dependent upon leucine concentration in the media; (3) overexpression of proteins that increase intracellular leucine confer resistance to dieldrin; (4) leucine uptake is inhibited in the presence of dieldrin; and (5) dieldrin induces the amino acid starvation response. Additionally, we demonstrate that appropriate negative regulation of the Ras/protein kinase A pathway, along with an intact pyruvate dehydrogenase complex, is required for dieldrin tolerance. Many yeast genes described in this study have human orthologs that may modulate dieldrin toxicity in humans. PMID:23358190

  1. Deletion of CGI-58 or adipose triglyceride lipase differently affects macrophage function and atherosclerosis[S

    PubMed Central

    Goeritzer, Madeleine; Schlager, Stefanie; Radovic, Branislav; Madreiter, Corina T.; Rainer, Silvia; Thomas, Gwynneth; Lord, Caleb C.; Sacks, Jessica; Brown, Amanda L.; Vujic, Nemanja; Obrowsky, Sascha; Sachdev, Vinay; Kolb, Dagmar; Chandak, Prakash G.; Graier, Wolfgang F.; Sattler, Wolfgang; Brown, J. Mark; Kratky, Dagmar

    2014-01-01

    Cellular TG stores are efficiently hydrolyzed by adipose TG lipase (ATGL). Its coactivator comparative gene identification-58 (CGI-58) strongly increases ATGL-mediated TG catabolism in cell culture experiments. To investigate the consequences of CGI-58 deficiency in murine macrophages, we generated mice with a targeted deletion of CGI-58 in myeloid cells (macCGI-58−/− mice). CGI-58−/− macrophages accumulate intracellular TG-rich lipid droplets and have decreased phagocytic capacity, comparable to ATGL−/− macrophages. In contrast to ATGL−/− macrophages, however, CGI-58−/− macrophages have intact mitochondria and show no indications of mitochondrial apoptosis and endoplasmic reticulum stress, suggesting that TG accumulation per se lacks a significant role in processes leading to mitochondrial dysfunction. Another notable difference is the fact that CGI-58−/− macrophages adopt an M1-like phenotype in vitro. Finally, we investigated atherosclerosis susceptibility in macCGI-58/ApoE-double KO (DKO) animals. In response to high-fat/high-cholesterol diet feeding, DKO animals showed comparable plaque formation as observed in ApoE−/− mice. In agreement, antisense oligonucleotide-mediated knockdown of CGI-58 in LDL receptor−/− mice did not alter atherosclerosis burden in the aortic root. These results suggest that macrophage function and atherosclerosis susceptibility differ fundamentally in these two animal models with disturbed TG catabolism, showing a more severe phenotype by ATGL deficiency. PMID:25316883

  2. Genome-wide functional screen identifies a compendium of genes affecting sensitivity to tamoxifen

    PubMed Central

    Mendes-Pereira, Ana M.; Sims, David; Dexter, Tim; Fenwick, Kerry; Assiotis, Ioannis; Kozarewa, Iwanka; Mitsopoulos, Costas; Hakas, Jarle; Zvelebil, Marketa; Lord, Christopher J.; Ashworth, Alan

    2012-01-01

    Therapies that target estrogen signaling have made a very considerable contribution to reducing mortality from breast cancer. However, resistance to tamoxifen remains a major clinical problem. Here we have used a genome-wide functional profiling approach to identify multiple genes that confer resistance or sensitivity to tamoxifen. Combining whole-genome shRNA screening with massively parallel sequencing, we have profiled the impact of more than 56,670 RNA interference reagents targeting 16,487 genes on the cellular response to tamoxifen. This screen, along with subsequent validation experiments, identifies a compendium of genes whose silencing causes tamoxifen resistance (including BAP1, CLPP, GPRC5D, NAE1, NF1, NIPBL, NSD1, RAD21, RARG, SMC3, and UBA3) and also a set of genes whose silencing causes sensitivity to this endocrine agent (C10orf72, C15orf55/NUT, EDF1, ING5, KRAS, NOC3L, PPP1R15B, RRAS2, TMPRSS2, and TPM4). Multiple individual genes, including NF1, a regulator of RAS signaling, also correlate with clinical outcome after tamoxifen treatment. PMID:21482774

  3. Ecosystem structure, function, and composition in rangelands are negatively affected by livestock grazing.

    PubMed

    Eldridge, David J; Poore, Alistair G B; Ruiz-Colmenero, Marta; Letnic, Mike; Soliveres, Santiago

    2016-06-01

    Reports of positive or neutral effects of grazing on plant species richness have prompted calls for livestock grazing to be used as a tool for managing land for conservation. Grazing effects, however, are likely to vary among different response variables, types, and intensity of grazing, and across abiotic conditions. We aimed to examine how grazing affects ecosystem structure, function, and composition. We compiled a database of 7615 records reporting an effect of grazing by sheep and cattle on 278 biotic and abiotic response variables for published studies across Australia. Using these data, we derived three ecosystem measures based on structure, function, and composition, which were compared against six contrasts of grazing pressure, ranging from low to heavy, two different herbivores (sheep, cattle), and across three different climatic zones. Grazing reduced structure (by 35%), function (24%), and composition (10%). Structure and function (but not composition) declined more when grazed by sheep and cattle together than sheep alone. Grazing reduced plant biomass (40%), animal richness (15%), and plant and animal abundance, and plant and litter cover (25%), but had no effect on plant richness nor soil function. The negative effects of grazing on plant biomass, plant cover, and soil function were more pronounced in drier environments. Grazing effects on plant and animal richness and composition were constant, or even declined, with increasing aridity. Our study represents a comprehensive continental assessment of the implications of grazing for managing Australian rangelands. Grazing effects were largely negative, even at very low levels of grazing. Overall, our results suggest that livestock grazing in Australia is unlikely to produce positive outcomes for ecosystem structure, function, and composition or even as a blanket conservation tool unless reduction in specific response variables is an explicit management objective. PMID:27509764

  4. A genome-wide screen for genes affecting eisosomes reveals Nce102 function in sphingolipid signaling

    PubMed Central

    Fröhlich, Florian; Moreira, Karen; Aguilar, Pablo S.; Hubner, Nina C.; Mann, Matthias; Walter, Peter

    2009-01-01

    The protein and lipid composition of eukaryotic plasma membranes is highly dynamic and regulated according to need. The sphingolipid-responsive Pkh kinases are candidates for mediating parts of this regulation, as they affect a diverse set of plasma membrane functions, such as cortical actin patch organization, efficient endocytosis, and eisosome assembly. Eisosomes are large protein complexes underlying the plasma membrane and help to sort a group of membrane proteins into distinct domains. In this study, we identify Nce102 in a genome-wide screen for genes involved in eisosome organization and Pkh kinase signaling. Nce102 accumulates in membrane domains at eisosomes where Pkh kinases also localize. The relative abundance of Nce102 in these domains compared with the rest of the plasma membrane is dynamically regulated by sphingolipids. Furthermore, Nce102 inhibits Pkh kinase signaling and is required for plasma membrane organization. Therefore, Nce102 might act as a sensor of sphingolipids that regulates plasma membrane function. PMID:19564405

  5. Aging. Aging-induced type I interferon signaling at the choroid plexus negatively affects brain function

    PubMed Central

    Baruch, Kuti; Deczkowska, Aleksandra; David, Eyal; Castellano, Joseph M.; Miller, Omer; Kertser, Alexander; Berkutzki, Tamara; Barnett-Itzhaki, Zohar; Bezalel, Dana; Wyss-Coray, Tony; Amit, Ido; Schwartz, Michal

    2016-01-01

    Age-associated cognitive decline is affected by factors produced inside and outside the brain. We found in aged mice and humans, that the choroid plexus (CP), an epithelial interface between the brain and the circulation, shows a type I interferon (IFN-I)-dependent expression profile, often associated with anti-viral responses. This signature was induced by brain-derived signals present in the cerebrospinal fluid of aged mice. Blocking IFN-I signaling within the brain of cognitively-impaired aged mice, using IFN-I receptor neutralizing antibody, led to partial restoration of cognitive function and hippocampal neurogenesis, and reestablished IFN-II-dependent CP activity, lost in aging. Our data identify an aging-induced IFN-I signature at the CP, and demonstrate its negative influence on brain function, thereby suggesting a potential target for therapeutic intervention for age-related cognitive decline. PMID:25147279

  6. Metabolic stressors and signals differentially affect energy allocation between reproduction and immune function.

    PubMed

    Carlton, Elizabeth D; Cooper, Candace L; Demas, Gregory E

    2014-11-01

    Most free-living animals have finite energy stores that they must allocate to different physiological and behavioral processes. In times of energetic stress, trade-offs in energy allocation among these processes may occur. The manifestation of trade-offs may depend on the source (e.g., glucose, lipids) and severity of energy limitation. In this study, we investigated energetic trade-offs between the reproductive and immune systems by experimentally limiting energy availability to female Siberian hamsters (Phodopus sungorus) with 2-deoxy-d-glucose, a compound that disrupts cellular utilization of glucose. We observed how glucoprivation at two levels of severity affected allocation to reproduction and immunity. Additionally, we treated a subset of these hamsters with leptin, an adipose hormone that provides a direct signal of available fat stores, in order to determine how increasing this signal of fat stores influences glucoprivation-induced trade-offs. We observed trade-offs between the reproductive and immune systems and that these trade-offs depended on the severity of energy limitation and exogenous leptin signaling. The majority of the animals experiencing mild glucoprivation entered anestrus, whereas leptin treatment restored estrous cycling in these animals. Surprisingly, virtually all animals experiencing more severe glucoprivation maintained normal estrous cycling throughout the experiment; however, exogenous leptin resulted in lower antibody production in this group. These data suggest that variation in these trade-offs may be mediated by shifts between glucose and fatty acid utilization. Collectively, the results of the present study highlight the context-dependent nature of these trade-offs, as trade-offs induced by the same metabolic stressor can manifest differently depending on its intensity. PMID:25125082

  7. Factors affecting recovery of postoperative bowel function after pediatric laparoscopic surgery

    PubMed Central

    Michelet, Daphnée; Andreu-Gallien, Juliette; Skhiri, Alia; Bonnard, Arnaud; Nivoche, Yves; Dahmani, Souhayl

    2016-01-01

    Background and Aims: Laparoscopic pediatric surgery allows a rapid postoperative rehabilitation and hospital discharge. However, the optimal postoperative pain management preserving advantages of this surgical technique remains to be determined. This study aimed to identify factors affecting the postoperative recovery of bowel function after laparoscopic surgery in children. Material and Methods: A retrospective analysis of factors affecting recovery of bowel function in children and infants undergoing laparoscopic surgery between January 1, 2009 and September 30, 2009, was performed. Factors included were: Age, weight, extent of surgery (extensive, regional or local), chronic pain (sickle cell disease or chronic intestinal inflammatory disease), American Society of Anaesthesiologists status, postoperative analgesia (ketamine, morphine, nalbuphine, paracetamol, nonsteroidal anti-inflammatory drugs [NSAIDs], nefopam, regional analgesia) both in the Postanesthesia Care Unit and in the surgical ward; and surgical complications. Data analysis used classification and regression tree analysis (CART) with a 10-fold cross validation. Results: One hundred and sixty six patients were included in the analysis. Recovery of bowel function depended upon: The extent of surgery, the occurrence of postoperative surgical complications, the administration of postoperative morphine in the surgical ward, the coadministration of paracetamol and NSAIDs and/or nefopam in the surgical ward and the emergency character of the surgery. The CART method generated a decision tree with eight terminal nodes. The percentage of explained variability of the model and the cross validation were 58% and 49%, respectively. Conclusion: Multimodal analgesia using nonopioid analgesia that allows decreasing postoperative morphine consumption should be considered for the speed of bowel function recovery after laparoscopic pediatric surgery.

  8. Functional Connectivity under Anticipation of Shock: Correlates of Trait Anxious Affect versus Induced Anxiety.

    PubMed

    Bijsterbosch, Janine; Smith, Stephen; Bishop, Sonia J

    2015-09-01

    Sustained anxiety about potential future negative events is an important feature of anxiety disorders. In this study, we used a novel anticipation of shock paradigm to investigate individual differences in functional connectivity during prolonged threat of shock. We examined the correlates of between-participant differences in trait anxious affect and induced anxiety, where the latter reflects changes in self-reported anxiety resulting from the shock manipulation. Dissociable effects of trait anxious affect and induced anxiety were observed. Participants with high scores on a latent dimension of anxious affect showed less increase in ventromedial pFC-amygdala connectivity between periods of safety and shock anticipation. Meanwhile, lower levels of induced anxiety were linked to greater augmentation of dorsolateral pFC-anterior insula connectivity during shock anticipation. These findings suggest that ventromedial pFC-amygdala and dorsolateral pFC-insula networks might both contribute to regulation of sustained fear responses, with their recruitment varying independently across participants. The former might reflect an evolutionarily old mechanism for reducing fear or anxiety, whereas the latter might reflect a complementary mechanism by which cognitive control can be implemented to diminish fear responses generated due to anticipation of aversive stimuli or events. These two circuits might provide complementary, alternate targets for exploration in future pharmacological and cognitive intervention studies. PMID:25961638

  9. Noise affects the shape of female preference functions for acoustic signals.

    PubMed

    Reichert, Michael S; Ronacher, Bernhard

    2015-02-01

    The shape of female mate preference functions influences the speed and direction of sexual signal evolution. However, the expression of female preferences is modulated by interactions between environmental conditions and the female's sensory processing system. Noise is an especially relevant environmental condition because it interferes directly with the neural processing of signals. Although noise is therefore likely a significant force in the evolution of communication systems, little is known about its effects on preference function shape. In the grasshopper Chorthippus biguttulus, female preferences for male calling song characteristics are likely to be affected by noise because its auditory system is sensitive to fine temporal details of songs. We measured female preference functions for variation in male song characteristics in several levels of masking noise and found strong effects of noise on preference function shape. The overall responsiveness to signals in noise generally decreased. Preference strength increased for some signal characteristics and decreased for others, largely corresponding to expectations based on neurophysiological studies of acoustic signal processing. These results suggest that different signal characteristics will be favored under different noise conditions, and thus that signal evolution may proceed differently depending on the extent and temporal patterning of environmental noise. PMID:25546134

  10. Light availability affects stream biofilm bacterial community composition and function, but not diversity

    PubMed Central

    Wagner, Karoline; Besemer, Katharina; Burns, Nancy R.; Battin, Tom J.

    2015-01-01

    Summary Changes in riparian vegetation or water turbidity and browning in streams alter the local light regime with potential implications for stream biofilms and ecosystem functioning. We experimented with biofilms in microcosms grown under a gradient of light intensities (range: 5–152 μmole photons s−1 m−2) and combined 454‐pyrosequencing and enzymatic activity assays to evaluate the effects of light on biofilm structure and function. We observed a shift in bacterial community composition along the light gradient, whereas there was no apparent change in alpha diversity. Multifunctionality, based on extracellular enzymes, was highest under high light conditions and decoupled from bacterial diversity. Phenol oxidase activity, involved in the degradation of polyphenolic compounds, was twice as high on average under the lowest compared with the highest light condition. This suggests a shift in reliance of microbial heterotrophs on biofilm phototroph‐derived organic matter under high light availability to more complex organic matter under low light. Furthermore, extracellular enzyme activities correlated with nutrient cycling and community respiration, supporting the link between biofilm structure–function and biogeochemical fluxes in streams. Our findings demonstrate that changes in light availability are likely to have significant impacts on biofilm structure and function, potentially affecting stream ecosystem processes. PMID:26013911

  11. Surface chemical functionalities affect the behavior of human adipose-derived stem cells in vitro

    NASA Astrophysics Data System (ADS)

    Liu, Xujie; Feng, Qingling; Bachhuka, Akash; Vasilev, Krasimir

    2013-04-01

    This study examines the effect of surface chemical functionalities on the behavior of human adipose-derived stem cells (hASCs) in vitro. Plasma polymerized films rich in amine (sbnd NH2), carboxyl (sbnd COOH) and methyl (sbnd CH3), were generated on hydroxyapatite (HAp) substrates. The surface chemical functionalities were characterized by X-ray photoelectron spectroscopy (XPS). The ability of different substrates to absorb proteins was evaluated. The results showed that substrates modified with hydrophilic functional group (sbnd COOH and sbnd NH2) can absorb more proteins than these modified with more hydrophobic functional group (sbnd CH3). The behavior of human adipose-derived stem cells (hASCs) cultured on different substrates was investigated in vitro: cell counting kit-8 (CCK-8) analysis was used to characterize cell proliferation, scanning electronic microscopy (SEM) analysis was used to characterize cell morphology and alkaline phosphatase (ALP) activity analysis was used to account for differentiation. The results of this study demonstrated that the sbnd NH2 modified surfaces encourage osteogenic differentiation; the sbnd COOH modified surfaces promote cell adhesion and spreading and the sbnd CH3 modified surfaces have the lowest ability to induce osteogenic differentiation. These findings confirmed that the surface chemical states of biomaterials can affect the behavior of hASCs in vitro.

  12. Predicting self-care with patients and family members' affective states and family functioning.

    PubMed

    Musci, E C; Dodd, M J

    1990-01-01

    People with cancer manage the side effects of treatment with the assistance of their family members. This study was designed to describe self-care behaviors (SCBs) initiated by patients and their family members and to determine the relationship between patients and family members' affective states and family functioning and SCBs. Using a longitudinal design, 42 patients and 40 family members were followed during 3 cycles of chemotherapy (12-16 weeks). The patients completed measures of affective state (POMS) each cycle; patients and family members completed a family functioning measure (F-COPES) at second cycle only; and the patients reported in an SCB log on an ongoing basis. The overall pattern of SCBs corroborated previous findings. The average number of SCBs initiated was 1.4 per side effect. Depression and vigor significantly predicted SCBs at Cycle 1 only. The severity of side effects consistently predicted SCB over the 3 cycles (r 2 = -0.39 to -0.46). Patients who experienced more severe side effects were at risk of diminished self-care. PMID:2342973

  13. Family Functioning and Child Behavioral Problems in Households Affected by HIV and AIDS in Kenya.

    PubMed

    Thurman, Tonya R; Kidman, Rachel; Nice, Johanna; Ikamari, Lawrence

    2015-08-01

    HIV places acute stressors on affected children and families; especially in resource limited contexts like sub-Saharan Africa. Despite their importance, the epidemic's potential consequences for family dynamics and children's psychological health are understudied. Using a population-based sample of 2,487 caregivers and 3,423 children aged 8-14 years from the Central Province of Kenya, analyses were conducted to examine whether parental illness and loss were associated with family functioning and children's externalizing behaviors. After controlling for demographics, a significant relationship between parental illness and externalizing behaviors was found among children of both genders. Orphan status was associated with behavioral problems among only girls. Regardless of gender, children experiencing both parental loss and illness fared the worst. Family functioning measured from the perspective of both caregivers and children also had an independent and important relationship with behavioral problems. Findings suggest that psychological and behavioral health needs may be elevated in households coping with serious illness and reiterate the importance of a family-centered approach for HIV-affected children. PMID:25205474

  14. Arabidopsis AtADF1 is functionally affected by mutations on actin binding sites.

    PubMed

    Dong, Chun-Hai; Tang, Wei-Ping; Liu, Jia-Yao

    2013-03-01

    The plant actin depolymerizing factor (ADF) binds to both monomeric and filamentous actin, and is directly involved in the depolymerization of actin filaments. To better understand the actin binding sites of the Arabidopsis thaliana L. AtADF1, we generated mutants of AtADF1 and investigated their functions in vitro and in vivo. Analysis of mutants harboring amino acid substitutions revealed that charged residues (Arg98 and Lys100) located at the α-helix 3 and forming an actin binding site together with the N-terminus are essential for both G- and F-actin binding. The basic residues on the β-strand 5 (K82/A) and the α-helix 4 (R135/A, R137/A) form another actin binding site that is important for F-actin binding. Using transient expression of CFP-tagged AtADF1 mutant proteins in onion (Allium cepa) peel epidermal cells and transgenic Arabidopsis thaliana L. plants overexpressing these mutants, we analyzed how these mutant proteins regulate actin organization and affect seedling growth. Our results show that the ADF mutants with a lower affinity for actin filament binding can still be functional, unless the affinity for actin monomers is also affected. The G-actin binding activity of the ADF plays an essential role in actin binding, depolymerization of actin polymers, and therefore in the control of actin organization. PMID:23190411

  15. Climate change induced rainfall patterns affect wheat productivity and agroecosystem functioning dependent on soil types

    NASA Astrophysics Data System (ADS)

    Tabi Tataw, James; Baier, Fabian; Krottenthaler, Florian; Pachler, Bernadette; Schwaiger, Elisabeth; Whylidal, Stefan; Formayer, Herbert; Hösch, Johannes; Baumgarten, Andreas; Zaller, Johann G.

    2014-05-01

    Wheat is a crop of global importance supplying more than half of the world's population with carbohydrates. We examined, whether climate change induced rainfall patterns towards less frequent but heavier events alter wheat agroecosystem productivity and functioning under three different soil types. Therefore, in a full-factorial experiment Triticum aestivum L. was cultivated in 3 m2 lysimeter plots containing the soil types sandy calcaric phaeozem, gleyic phaeozem or calcic chernozem. Prognosticated rainfall patterns based on regionalised climate change model calculations were compared with current long-term rainfall patterns; each treatment combination was replicated three times. Future rainfall patterns significantly reduced wheat growth and yield, reduced the leaf area index, accelerated crop development, reduced arbuscular mycorrhizal fungi colonisation of roots, increased weed density and the stable carbon isotope signature (δ13C) of both old and young wheat leaves. Different soil types affected wheat growth and yield, ecosystem root production as well as weed abundance and biomass. The interaction between climate and soil type was significant only for the harvest index. Our results suggest that even slight changes in rainfall patterns can significantly affect the functioning of wheat agroecosystems. These rainfall effects seemed to be little influenced by soil types suggesting more general impacts of climate change across different soil types. Wheat production under future conditions will likely become more challenging as further concurrent climate change factors become prevalent.

  16. DNA Hypomethylation Affects Cancer-Related Biological Functions and Genes Relevant in Neuroblastoma Pathogenesis

    PubMed Central

    Mayol, Gemma; Martín-Subero, José I.; Ríos, José; Queiros, Ana; Kulis, Marta; Suñol, Mariona; Esteller, Manel; Gómez, Soledad; Garcia, Idoia; de Torres, Carmen; Rodríguez, Eva; Galván, Patricia; Mora, Jaume; Lavarino, Cinzia

    2012-01-01

    Neuroblastoma (NB) pathogenesis has been reported to be closely associated with numerous genetic alterations. However, underlying DNA methylation patterns have not been extensively studied in this developmental malignancy. Here, we generated microarray-based DNA methylation profiles of primary neuroblastic tumors. Stringent supervised differential methylation analyses allowed us to identify epigenetic changes characteristic for NB tumors as well as for clinical and biological subtypes of NB. We observed that gene-specific loss of DNA methylation is more prevalent than promoter hypermethylation. Remarkably, such hypomethylation affected cancer-related biological functions and genes relevant to NB pathogenesis such as CCND1, SPRR3, BTC, EGF and FGF6. In particular, differential methylation in CCND1 affected mostly an evolutionary conserved functionally relevant 3′ untranslated region, suggesting that hypomethylation outside promoter regions may play a role in NB pathogenesis. Hypermethylation targeted genes involved in cell development and proliferation such as RASSF1A, POU2F2 or HOXD3, among others. The results derived from this study provide new candidate epigenetic biomarkers associated with NB as well as insights into the molecular pathogenesis of this tumor, which involves a marked gene-specific hypomethylation. PMID:23144874

  17. Breakfast Staple Types Affect Brain Gray Matter Volume and Cognitive Function in Healthy Children

    PubMed Central

    Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Takeuchi, Hikaru; Asano, Michiko; Asano, Kohei; Kawashima, Ryuta

    2010-01-01

    Childhood diet is important for brain development. Furthermore, the quality of breakfast is thought to affect the cognitive functioning of well-nourished children. To analyze the relationship among breakfast staple type, gray matter volume, and intelligence quotient (IQ) in 290 healthy children, we used magnetic resonance images and applied voxel-based morphometry. We divided subjects into rice, bread, and both groups according to their breakfast staple. We showed that the rice group had a significantly larger gray matter ratio (gray matter volume percentage divided by intracranial volume) and significantly larger regional gray matter volumes of several regions, including the left superior temporal gyrus. The bread group had significantly larger regional gray and white matter volumes of several regions, including the right frontoparietal region. The perceptual organization index (POI; IQ subcomponent) of the rice group was significantly higher than that of the bread group. All analyses were adjusted for age, gender, intracranial volume, socioeconomic status, average weekly frequency of having breakfast, and number of side dishes eaten for breakfast. Although several factors may have affected the results, one possible mechanism underlying the difference between the bread and the rice groups may be the difference in the glycemic index (GI) of these two substances; foods with a low GI are associated with less blood-glucose fluctuation than are those with a high GI. Our study suggests that breakfast staple type affects brain gray and white matter volumes and cognitive function in healthy children; therefore, a diet of optimal nutrition is important for brain maturation during childhood and adolescence. PMID:21170334

  18. Sydnone SYD-1 affects the metabolic functions of isolated rat hepatocytes.

    PubMed

    Brandt, Anna Paula; Pires, Amanda do Rocio Andrade; Rocha, Maria Eliane Merlin; Noleto, Guilhermina Rodrigues; Acco, Alexandra; de Souza, Carlos Eduardo Alves; Echevarria, Aurea; Canuto, André Vinícius dos Santos; Cadena, Sílvia Maria Suter Correia

    2014-07-25

    Previously, we demonstrated that sydnone SYD-1 (3-[4-chloro-3-nitrophenyl]-1,2,3-oxadiazolium-5-olate) impairs the mitochondrial functions linked to energy provision and suggested that this effect could be associated with its antitumor activity. Herein, we evaluated the effects of SYD-1 (25 and 50 μM) on rat hepatocytes to determine its cytotoxicity on non-tumor cells. SYD-1 (25 and 50 μM) did not affect the viability of hepatocytes in suspension after 1-40 min of incubation. However, the viability of the cultured hepatocytes was decreased by ∼66% as a consequence of treatment with SYD-1 (50 μM) for 18 h. Under the same conditions, SYD-1 promoted an increase in the release of LDH by ∼19%. The morphological changes in the cultured cells treated with SYD-1 (50 μM) were suggestive of cell distress, which was demonstrated by the presence of rounded hepatocytes, cell fragments and monolayer impairment. Furthermore, fluorescence microscopy showed an increase in the annexin label after treatment with SYD-1 (50 μM), suggesting that apoptosis had been induced in these cells. SYD-1 did not affect the states of respiration in the suspended hepatocytes, but the pyruvate levels were decreased by ∼36%, whereas the lactate levels were increased by ∼22% (for the 50 μM treatment). The basal and uncoupled states of respiration of the cultured hepatocytes were inhibited by ∼79% and ∼51%, respectively, by SYD-1 (50 μM). In these cells, SYD-1 (50 μM) increased the pyruvate and lactate levels by ∼84% and ∼16%, respectively. These results show that SYD-1 affects important metabolic functions related to energy provision in hepatocytes and that this effect was more pronounced on cells in culture than those in suspension. PMID:24836382

  19. Loss of Cellular Sialidases Does Not Affect the Sialylation Status of the Prion Protein but Increases the Amounts of Its Proteolytic Fragment C1

    PubMed Central

    Katorcha, Elizaveta; Klimova, Nina; Makarava, Natallia; Savtchenko, Regina; Pan, Xuefang; Annunziata, Ida; Takahashi, Kohta; Miyagi, Taeko; Pshezhetsky, Alexey V.; d’Azzo, Alessandra; Baskakov, Ilia V.

    2015-01-01

    The central molecular event underlying prion diseases involves conformational change of the cellular form of the prion protein (PrPC), which is a sialoglycoprotein, into the disease-associated, transmissible form denoted PrPSc. Recent studies revealed a correlation between the sialylation status of PrPSc and incubation time to disease and introduced a new hypothesis that progression of prion diseases could be controlled or reversed by altering the sialylation level of PrPC. Of the four known mammalian sialidases, the enzymes that cleave off sialic acid residues, only NEU1, NEU3 and NEU4 are expressed in the brain. To test whether cellular sialidases control the steady-state sialylation level of PrPC and to identify the putative sialidase responsible for desialylating PrPC, we analyzed brain-derived PrPC from knockout mice deficient in Neu1, Neu3, Neu4, or from Neu3/Neu4 double knockouts. Surprisingly, no differences in the sialylation of PrPC or its proteolytic product C1 were noticed in any of the knockout mice tested as compared to the age-matched controls. However, significantly higher amounts of the C1 fragment relative to full-length PrPC were detected in the brains of Neu1 knockout mice as compared to WT mice or to the other knockout mice. Additional experiments revealed that in neuroblastoma cell line the sialylation pattern of C1 could be changed by an inhibitor of sialylatransferases. In summary, this study suggests that targeting cellular sialidases is apparently not the correct strategy for altering the sialylation levels of PrPC, whereas modulating the activity of sialylatransferases might offer a more promising approach. Our findings also suggest that catabolism of PrPC involves its α-cleavage followed by desialylation of the resulting C1 fragments by NEU1 and consequent fast degradation of the desialylated products. PMID:26569607

  20. High Basal Activity of the PTPN22 Gain-of-Function Variant Blunts Leukocyte Responsiveness Negatively Affecting IL-10 Production in ANCA Vasculitis

    PubMed Central

    Cao, Yali; Yang, Jiajin; Colby, Kerry; Hogan, Susan L.; Hu, Yichun; Jennette, Caroline E.; Berg, Elisabeth A.; Zhang, Youkang; Jennette, J. Charles; Falk, Ronald J.; Preston, Gloria A.

    2012-01-01

    Consequences of expression of the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gain-of-function variant were evaluated in leukocytes from patients with anti-neutrophil cytoplasmic autoantibody (ANCA) disease. The frequency of the gain-of-function allele within the Caucasian patient cohort was 22% (OR 1.45), compared to general American Caucasian population (16.5%, p = 0.03). Examination of the basal phosphatase activity of PTPN22 gain-of-function protein indicated persistently elevated activity in un-stimulated peripheral leukocytes, while basal activity was undetectable in leukocytes from patients without the gain-of-function variant. To examine consequences of persistently high PTPN22 activity, the activation status of ERK and p38 MAPK were analyzed. While moderate levels of activated ERK were observed in controls, it was undetectable in leukocytes expressing PTPN22 gain-of-function protein and instead p38MAPK was up-regulated. IL-10 transcription, reliant on the ERK pathway, was negatively affected. Over the course of disease, patients expressing variant PTPN22 did not show a spike in IL-10 transcription as they entered remission in contrast to controls, implying that environmentally triggered signals were blunted. Sustained activity of PTPN22, due to the gain-of-function mutation, acts as a dominant negative regulator of ERK activity leading to blunted cellular responsiveness to environmental stimuli and expression of protective cytokines. PMID:22880107

  1. Analysis of Common and Specific Mechanisms of Liver Function Affected by Nitrotoluene Compounds

    PubMed Central

    Deng, Youping; Meyer, Sharon A.; Guan, Xin; Escalon, Barbara Lynn; Ai, Junmei; Wilbanks, Mitchell S.; Welti, Ruth; Garcia-Reyero, Natàlia; Perkins, Edward J.

    2011-01-01

    Background Nitrotoluenes are widely used chemical manufacturing and munitions applications. This group of chemicals has been shown to cause a range of effects from anemia and hypercholesterolemia to testicular atrophy. We have examined the molecular and functional effects of five different, but structurally related, nitrotoluenes on using an integrative systems biology approach to gain insight into common and disparate mechanisms underlying effects caused by these chemicals. Methodology/Principal Findings Sprague-Dawley female rats were exposed via gavage to one of five concentrations of one of five nitrotoluenes [2,4,6-trinitrotoluene (TNT), 2-amino-4,6-dinitrotoluene (2ADNT) 4-amino-2,6-dinitrotoulene (4ADNT), 2,4-dinitrotoluene (2,4DNT) and 2,6-dinitrotoluene (2,6DNT)] with necropsy and tissue collection at 24 or 48 h. Gene expression profile results correlated well with clinical data and liver histopathology that lead to the concept that hematotoxicity was followed by hepatotoxicity. Overall, 2,4DNT, 2,6DNT and TNT had stronger effects than 2ADNT and 4ADNT. Common functional terms, gene expression patterns, pathways and networks were regulated across all nitrotoluenes. These pathways included NRF2-mediated oxidative stress response, aryl hydrocarbon receptor signaling, LPS/IL-1 mediated inhibition of RXR function, xenobiotic metabolism signaling and metabolism of xenobiotics by cytochrome P450. One biological process common to all compounds, lipid metabolism, was found to be impacted both at the transcriptional and lipid production level. Conclusions/Significance A systems biology strategy was used to identify biochemical pathways affected by five nitroaromatic compounds and to integrate data that tie biochemical alterations to pathological changes. An integrative graphical network model was constructed by combining genomic, gene pathway, lipidomic, and physiological endpoint results to better understand mechanisms of liver toxicity and physiological endpoints

  2. Earthworm-Mycorrhiza Interactions Can Affect the Diversity, Structure and Functioning of Establishing Model Grassland Communities

    PubMed Central

    Zaller, Johann G.; Heigl, Florian; Grabmaier, Andrea; Lichtenegger, Claudia; Piller, Katja; Allabashi, Roza; Frank, Thomas; Drapela, Thomas

    2011-01-01

    Both earthworms and arbuscular mycorrhizal fungi (AMF) are important ecosystem engineers co-occurring in temperate grasslands. However, their combined impacts during grassland establishment are poorly understood and have never been studied. We used large mesocosms to study the effects of different functional groups of earthworms (i.e., vertically burrowing anecics vs. horizontally burrowing endogeics) and a mix of four AMF taxa on the establishment, diversity and productivity of plant communities after a simulated seed rain of 18 grassland species comprising grasses, non-leguminous forbs and legumes. Moreover, effects of earthworms and/or AMF on water infiltration and leaching of ammonium, nitrate and phosphate were determined after a simulated extreme rainfall event (40 l m−2). AMF colonisation of all three plant functional groups was altered by earthworms. Seedling emergence and diversity was reduced by anecic earthworms, however only when AMF were present. Plant density was decreased in AMF-free mesocosms when both anecic and endogeic earthworms were active; with AMF also anecics reduced plant density. Plant shoot and root biomass was only affected by earthworms in AMF-free mesocosms: shoot biomass increased due to the activity of either anecics or endogeics; root biomass increased only when anecics were active. Water infiltration increased when earthworms were present in the mesocosms but remained unaffected by AMF. Ammonium leaching was increased only when anecics or a mixed earthworm community was active but was unaffected by AMF; nitrate and phosphate leaching was neither affected by earthworms nor AMF. Ammonium leaching decreased with increasing plant density, nitrate leaching decreased with increasing plant diversity and density. In order to understand the underlying processes of these interactions further investigations possibly under field conditions using more diverse belowground communities are required. Nevertheless, this study demonstrates that

  3. Synthesis, solubilization, and surface functionalization of highly fluorescent quantum dots for cellular targeting through a small molecule

    NASA Astrophysics Data System (ADS)

    Galloway, Justin F.

    To achieve long-term fluorescence imaging with quantum dots (QDs), a CdSe core/shell must first be synthesized. The synthesis of bright CdSe QDs is not trivial and as a consequence, the role of surfactant in nucleation and growth was investigated. It was found that the type of surfactant used, either phosphonic or fatty acid, played a pivotal role in the size of the CdSe core. The study of surfactant on CdSe synthesis, ultimately led to an electrical passivation method that utilized a short-chained phosphonic acid and highly reactive organometallic precursors to achieve high quantum yield (QY) as has been previously described. The synthesis of QDs using organometallic precursors and a phosphonic acid for passivation resulted in 4 out of 9 batches of QDs achieving QYs greater than 50% and 8 out of 9 batches with QYs greater than 35%. The synthesis of CdSe QDs was done in organic solutions rendering the surface of the particle hydrophobic. To perform cell-targeting experiments, QDs must be transferred to water. The transfer of QDs to water was successfully accomplished by using single acyl chain lipids. A systematic study of different lipid combinations and coatings demonstrated that 20-40 mol% single acyl chained lipids were able to transfer QDs to water resulting in monodispersed, stable QDs without adversely affecting the QY. The advantage to water solubilization using single acyl chain lipids is that the QD have a hydrodynamic radius less than 15 nm, QYs that can exceed 50% and additional surface functionalization can be down using the reactive sites incorporated into the lipid bilayer. QDs that are bright and stable in water were studied for the purpose of targeting G protein-coupled Receptors (GPCR). GPCRs are transmembrane receptors that internalize extracellular cues, and thus mediate signal transduction. The cyclic Adenosine Monophosphate Receptor 1 of the model organism Dictyostelium disodium was the receptor of interest. The Halo protein, a genetically

  4. Tetracapsuloides bryosalmonae infection affects the expression of genes involved in cellular signal transduction and iron metabolism in the kidney of the brown trout Salmo trutta.

    PubMed

    Kumar, Gokhlesh; Sarker, Subhodeep; Menanteau-Ledouble, Simon; El-Matbouli, Mansour

    2015-06-01

    Tetracapsuloides bryosalmonae is an enigmatic endoparasite which causes proliferative kidney disease in various species of salmonids in Europe and North America. The life cycle of the European strain of T. bryosalmonae generally completes in an invertebrate host freshwater bryozoan and vertebrate host brown trout (Salmo trutta) Linnaeus, 1758. Little is known about the gene expression in the kidney of brown trout during the developmental stages of T. bryosalmonae. In the present study, quantitative real-time PCR was applied to quantify the target genes of interest in the kidney of brown trout at different time points of T. bryosalmonae development. PCR primers specific for target genes were designed and optimized, and their gene expression levels were quantified in the cDNA kidney samples using SYBR Green Supermix. Expression of Rab GDP dissociation inhibitor beta, integral membrane protein 2B, NADH dehydrogenase 1 beta subcomplex subunit 6, and 26S protease regulatory subunit S10B were upregulated significantly in infected brown trout, while the expression of the ferritin M middle subunit was downregulated significantly. These results suggest that host genes involved in cellular signal transduction, proteasomal activities, including membrane transporters and cellular iron storage, are differentially upregulated or downregulated in the kidney of brown trout during parasite development. The gene expression pattern of infected renal tissue may support the development of intraluminal sporogonic stages of T. bryosalmonae in the renal tubular lumen of brown trout which may facilitate the release of viable parasite spores to transmit to the invertebrate host bryozoan. PMID:25786607

  5. Muscle disuse alters skeletal muscle contractile function at the molecular and cellular levels in older adult humans in a sex-specific manner

    PubMed Central

    Callahan, Damien M; Miller, Mark S; Sweeny, Andrew P; Tourville, Timothy W; Slauterbeck, James R; Savage, Patrick D; Maugan, David W; Ades, Philip A; Beynnon, Bruce D; Toth, Michael J

    2014-01-01

    Physical inactivity that accompanies ageing and disease may hasten disability by reducing skeletal muscle contractility. To characterize skeletal muscle functional adaptations to muscle disuse, we compared contractile performance at the molecular, cellular and whole-muscle levels in healthy active older men and women (n = 15) and inactive older men and women with advanced-stage, symptomatic knee osteoarthritis (OA) (n = 16). OA patients showed reduced (P < 0.01) knee extensor function. At the cellular level, single muscle fibre force production was reduced in OA patients in myosin heavy chain (MHC) I and IIA fibres (both P < 0.05) and differences in IIA fibres persisted after adjustments for fibre cross-sectional area (P < 0.05). Although no group differences in contractile velocity or power output were found for any fibre type, sex was found to modify the effect of OA, with a reduction in MHC IIA power output and a trend towards reduced shortening velocity in women, but increases in both variables in men (P < 0.05 and P = 0.07, respectively). At the molecular level, these adaptations in MHC IIA fibre function were explained by sex-specific differences (P ≤ 0.05) in myosin–actin cross-bridge kinetics. Additionally, cross-bridge kinetics were slowed in MHC I fibres in OA patients (P < 0.01), attributable entirely to reductions in women with knee OA (P < 0.05), a phenotype that could be reproduced in vitro by chemical modification of protein thiol residues. Our results identify molecular and cellular functional adaptations in skeletal muscle that may contribute to reduced physical function with knee OA-associated muscle disuse, with sex-specific differences that may explain a greater disposition towards disability in women. PMID:25038243

  6. Postnatal nutritional restriction affects growth and immune function of piglets with intra-uterine growth restriction.

    PubMed

    Hu, Liang; Liu, Yan; Yan, Chuan; Peng, Xie; Xu, Qin; Xuan, Yue; Han, Fei; Tian, Gang; Fang, Zhengfeng; Lin, Yan; Xu, Shengyu; Zhang, Keying; Chen, Daiwen; Wu, De; Che, Lianqiang

    2015-07-14

    Postnatal rapid growth by excess intake of nutrients has been associated with an increased susceptibility to diseases in neonates with intra-uterine growth restricted (IUGR). The aim of the present study was to determine whether postnatal nutritional restriction could improve intestinal development and immune function of neonates with IUGR using piglets as model. A total of twelve pairs of normal-birth weight (NBW) and IUGR piglets (7 d old) were randomly assigned to receive adequate nutrient intake or restricted nutrient intake (RNI) by artificially liquid feeding for a period of 21 d. Blood samples and intestinal tissues were collected at necropsy and were analysed for morphology, digestive enzyme activities, immune cells and expression of innate immunity-related genes. The results indicated that both IUGR and postnatal nutritional restriction delayed the growth rate during the sucking period. Irrespective of nutrient intake, piglets with IUGR had a significantly lower villous height and crypt depth in the ileum than the NBW piglets. Moreover, IUGR decreased alkaline phosphatase activity while enhanced lactase activity in the jejunum and mRNA expressions of Toll-like receptor 9 (TLR-9) and DNA methyltransferase 1 (DNMT1) in the ileum of piglets. Irrespective of body weight, RNI significantly decreased the number and/or percentage of peripheral leucocytes, lymphocytes and monocytes of piglets, whereas the percentage of neutrophils and the ratio of CD4+ to CD8+ were increased. Furthermore, RNI markedly enhanced the mRNA expression of TLR-9 and DNMT1, but decreased the expression of NOD2 and TRAF-6 in the ileum of piglets. In summary, postnatal nutritional restriction led to abnormal cellular and innate immune response, as well as delayed the growth and intestinal development of IUGR piglets. PMID:26059215

  7. Herbivore species richness and feeding complementarity affect community structure and function on a coral reef

    PubMed Central

    Burkepile, Deron E.; Hay, Mark E.

    2008-01-01

    Consumer effects on prey are well known for cascading through food webs and producing dramatic top-down effects on community structure and ecosystem function. Bottom-up effects of prey (primary producer) biodiversity are also well known. However, the role of consumer diversity in affecting community structure or ecosystem function is not well understood. Here, we show that herbivore species richness can be critical for maintaining the structure and function of coral reefs. In two experiments over 2 years, we constructed large cages enclosing single herbivore species, equal densities of mixed species of herbivores, or excluding herbivores and assessed effects on both seaweeds and corals. When compared with single-herbivore treatments, mixed-herbivore treatments lowered macroalgal abundance by 54–76%, enhanced cover of crustose coralline algae (preferred recruitment sites for corals) by 52–64%, increased coral cover by 22%, and prevented coral mortality. Complementary feeding by herbivorous fishes drove the herbivore richness effects, because macroalgae were unable to effectively deter fishes with different feeding strategies. Maintaining herbivore species richness appears critical for preserving coral reefs, because complementary feeding by diverse herbivores produces positive, but indirect, effects on corals, the foundation species for the ecosystem. PMID:18845686

  8. Artefacts and biases affecting the evaluation of scoring functions on decoy sets for protein structure prediction

    PubMed Central

    Handl, Julia; Knowles, Joshua; Lovell, Simon C.

    2009-01-01

    Motivation: Decoy datasets, consisting of a solved protein structure and numerous alternative native-like structures, are in common use for the evaluation of scoring functions in protein structure prediction. Several pitfalls with the use of these datasets have been identified in the literature, as well as useful guidelines for generating more effective decoy datasets. We contribute to this ongoing discussion an empirical assessment of several decoy datasets commonly used in experimental studies. Results: We find that artefacts and sampling issues in the large majority of these data make it trivial to discriminate the native structure. This underlines that evaluation based on the rank/z-score of the native is a weak test of scoring function performance. Moreover, sampling biases present in the way decoy sets are generated or used can strongly affect other types of evaluation measures such as the correlation between score and root mean squared deviation (RMSD) to the native. We demonstrate how, depending on type of bias and evaluation context, sampling biases may lead to both over- or under-estimation of the quality of scoring terms, functions or methods. Availability: Links to the software and data used in this study are available at http://dbkgroup.org/handl/decoy_sets. Contact: simon.lovell@manchester.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:19297350

  9. Aesthetic and functional rehabilitation of the primary dentition affected by amelogenesis imperfecta.

    PubMed

    Marquezin, Maria Carolina Salomé; Zancopé, Bruna Raquel; Pacheco, Larissa Ferreira; Gavião, Maria Beatriz Duarte; Pascon, Fernanda Miori

    2015-01-01

    The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI) in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars with stainless steel crowns and resin-filled celluloid forms. The main objectives of the selected treatment were to enhance the esthetics, restore masticatory function, and eliminate the teeth sensitivity. The child was monitored in the pediatric dentistry clinic at four-month intervals until the mixed dentition stage. Treatment not only restored function and esthetic, but also showed a positive psychological impact and thereby improved perceived quality of life. The preventive, psychological, and curative measures of a young child with AI were successful. This result can encourage the clinicians to seek a cost-effective technique such as stainless steel crowns, and resin-filled celluloid forms to reestablish the oral functions and improve the child's psychosocial development. PMID:25705526

  10. Aesthetic and Functional Rehabilitation of the Primary Dentition Affected by Amelogenesis Imperfecta

    PubMed Central

    Marquezin, Maria Carolina Salomé; Zancopé, Bruna Raquel; Pacheco, Larissa Ferreira; Gavião, Maria Beatriz Duarte; Pascon, Fernanda Miori

    2015-01-01

    The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI) in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars with stainless steel crowns and resin-filled celluloid forms. The main objectives of the selected treatment were to enhance the esthetics, restore masticatory function, and eliminate the teeth sensitivity. The child was monitored in the pediatric dentistry clinic at four-month intervals until the mixed dentition stage. Treatment not only restored function and esthetic, but also showed a positive psychological impact and thereby improved perceived quality of life. The preventive, psychological, and curative measures of a young child with AI were successful. This result can encourage the clinicians to seek a cost-effective technique such as stainless steel crowns, and resin-filled celluloid forms to reestablish the oral functions and improve the child's psychosocial development. PMID:25705526

  11. SIRT1 reduces endothelial activation without affecting vascular function in ApoE-/- mice

    PubMed Central

    Stein, Sokrates; Schäfer, Nicola; Breitenstein, Alexander; Besler, Christian; Winnik, Stephan; Lohmann, Christine; Heinrich, Kathrin; Brokopp, Chad E.; Handschin, Christoph; Landmesser, Ulf; Tanner, Felix C.; Lüscher, Thomas F.; Matter, Christian M.

    2010-01-01

    Excessive production of reactive oxygen species (ROS) contributes to progression of atherosclerosis, at least in part by causing endothelial dysfunction and inflammatory activation. The class III histone deacetylase SIRT1 has been implicated in extension of lifespan. In the vasculature,SIRT1 gain-of-function using SIRT1 overexpression or activation has been shown to improve endothelial function in mice and rats via stimulation of endothelial nitric oxide (NO) synthase (eNOS). However, the effects of SIRT1 loss-of-function on the endothelium in atherosclerosis remain to be characterized. Thus, we have investigated the endothelial effects of decreased endogenous SIRT1 in hypercholesterolemic ApoE-/- mice. We observed no difference in endothelial relaxation and eNOS (Ser1177) phosphorylation between 20-week old male atherosclerotic ApoE-/- SIRT1+/- and ApoE-/- SIRT1+/+ mice. However, SIRT1 prevented endothelial superoxide production, inhibited NF-κB signaling, and diminished expression of adhesion molecules. Treatment of young hypercholesterolemic ApoE-/- SIRT1+/- mice with lipopolysaccharide to boost NF-κB signaling led to a more pronounced endothelial expression of ICAM-1 and VCAM-1 as compared to ApoE-/- SIRT1+/+ mice. In conclusion, endogenous SIRT1 diminishes endothelial activation in ApoE-/- mice, but does not affect endothelium-dependent vasodilatation. PMID:20606253

  12. Human CalDAG-GEFI gene (RASGRP2) mutation affects platelet function and causes severe bleeding

    PubMed Central

    Canault, Matthias; Ghalloussi, Dorsaf; Grosdidier, Charlotte; Guinier, Marie; Perret, Claire; Chelghoum, Nadjim; Germain, Marine; Raslova, Hana; Peiretti, Franck; Morange, Pierre E.; Saut, Noemie; Pillois, Xavier; Nurden, Alan T.; Cambien, François; Pierres, Anne; van den Berg, Timo K.; Kuijpers, Taco W.; Tregouet, David-Alexandre

    2014-01-01

    The nature of an inherited platelet disorder was investigated in three siblings affected by severe bleeding. Using whole-exome sequencing, we identified the culprit mutation (cG742T) in the RAS guanyl-releasing protein-2 (RASGRP2) gene coding for calcium- and DAG-regulated guanine exchange factor-1 (CalDAG-GEFI). Platelets from individuals carrying the mutation present a reduced ability to activate Rap1 and to perform proper αIIbβ3 integrin inside-out signaling. Expression of CalDAG-GEFI mutant in HEK293T cells abolished Rap1 activation upon stimulation. Nevertheless, the PKC- and ADP-dependent pathways allow residual platelet activation in the absence of functional CalDAG-GEFI. The mutation impairs the platelet’s ability to form thrombi under flow and spread normally as a consequence of reduced Rac1 GTP-binding. Functional deficiencies were confined to platelets and megakaryocytes with no leukocyte alteration. This contrasts with the phenotype seen in type III leukocyte adhesion deficiency caused by the absence of kindlin-3. Heterozygous did not suffer from bleeding and have normal platelet aggregation; however, their platelets mimicked homozygous ones by failing to undergo normal adhesion under flow and spreading. Rescue experiments on cultured patient megakaryocytes corrected the functional deficiency after transfection with wild-type RASGRP2. Remarkably, the presence of a single normal allele is sufficient to prevent bleeding, making CalDAG-GEFI a novel and potentially safe therapeutic target to prevent thrombosis. PMID:24958846

  13. Plant species richness and functional traits affect community stability after a flood event.

    PubMed

    Fischer, Felícia M; Wright, Alexandra J; Eisenhauer, Nico; Ebeling, Anne; Roscher, Christiane; Wagg, Cameron; Weigelt, Alexandra; Weisser, Wolfgang W; Pillar, Valério D

    2016-05-19

    Climate change is expected to increase the frequency and magnitude of extreme weather events. It is therefore of major importance to identify the community attributes that confer stability in ecological communities during such events. In June 2013, a flood event affected a plant diversity experiment in Central Europe (Jena, Germany). We assessed the effects of plant species richness, functional diversity, flooding intensity and community means of functional traits on different measures of stability (resistance, resilience and raw biomass changes from pre-flood conditions). Surprisingly, plant species richness reduced community resistance in response to the flood. This was mostly because more diverse communities grew more immediately following the flood. Raw biomass increased over the previous year; this resulted in decreased absolute value measures of resistance. There was no clear response pattern for resilience. We found that functional traits drove these changes in raw biomass: communities with a high proportion of late-season, short-statured plants with dense, shallow roots and small leaves grew more following the flood. Late-growing species probably avoided the flood, whereas greater root length density might have allowed species to better access soil resources brought from the flood, thus growing more in the aftermath. We conclude that resource inputs following mild floods may favour the importance of traits related to resource acquisition and be less associated with flooding tolerance. PMID:27114578

  14. Proliferation of Purple Sulphur Bacteria at the Sediment Surface Affects Intertidal Mat Diversity and Functionality

    PubMed Central

    Hubas, Cédric; Jesus, Bruno; Ruivo, Mickael; Meziane, Tarik; Thiney, Najet; Davoult, Dominique; Spilmont, Nicolas; Paterson, David M.; Jeanthon, Christian

    2013-01-01

    There is a relative absence of studies dealing with mats of purple sulphur bacteria in the intertidal zone. These bacteria display an array of metabolic pathways that allow them to disperse and develop under a wide variety of conditions, making these mats important in terms of ecosystem processes and functions. Mass blooms of purple sulphur bacteria develop during summer on sediments in the intertidal zone especially on macroalgal deposits. The microbial composition of different types of mats differentially affected by the development of purple sulphur bacteria was examined, at low tide, using a set of biochemical markers (fatty acids, pigments) and composition was assessed against their influence on ecosystem functions (sediment cohesiveness, CO2 fixation). We demonstrated that proliferation of purple sulphur bacteria has a major impact on intertidal mats diversity and functions. Indeed, assemblages dominated by purple sulphur bacteria (Chromatiaceae) were efficient exopolymer producers and their biostabilisation potential was significant. In addition, the massive growth of purple sulphur bacteria resulted in a net CO2 degassing whereas diatom dominated biofilms represented a net CO2 sink. PMID:24340018

  15. Inhibitory nitrosylation of mammalian thioredoxin reductase 1: Molecular characterization and evidence for its functional role in cellular nitroso-redox imbalance.

    PubMed

    Engelman, Rotem; Ziv, Tamar; Arnér, Elias S J; Benhar, Moran

    2016-08-01

    Mammalian thioredoxin 1 (Trx1) and the selenoprotein Trx reductase 1 (TrxR1) are key cellular enzymes that function coordinately in thiol-based redox regulation and signaling. Recent studies have revealed that the Trx1/TrxR1 system has an S-nitrosothiol reductase (denitrosylase) activity through which it can regulate nitric oxide-related cellular processes. In this study we revealed that TrxR1 is itself susceptible to nitrosylation, characterized the underlying mechanism, and explored its functional significance. We found that nitrosothiol or nitric oxide donating agents rapidly and effectively inhibited the activity of recombinant or endogenous TrxR1. In particular, the NADPH-reduced TrxR1 was partially and reversibly inhibited upon exposure to low concentrations (<10μM) of S-nitrosocysteine (CysNO) and markedly and continuously inhibited at higher doses. Concurrently, TrxR1 very efficiently reduced low, but not high, levels of CysNO. Biochemical and mass spectrometric analyses indicated that its active site selenocysteine residue renders TrxR1 highly susceptible to nitrosylation-mediated inhibition, and revealed both thiol and selenol modifications at the two redox active centers of the enzyme. Studies in HeLa cancer cells demonstrated that endogenous TrxR1 is sensitive to nitrosylation-dependent inactivation and pointed to an important role for glutathione in reversing or preventing this process. Notably, depletion of cellular glutathione with l-buthionine-sulfoximine synergized with nitrosating agents in promoting sustained nitrosylation and inactivation of TrxR1, events that were accompanied by significant oxidation of Trx1 and extensive cell death. Collectively, these findings expand our knowledge of the role and regulation of the mammalian Trx system in relation to cellular nitroso-redox imbalance. The observations raise the possibility of exploiting the nitrosylation susceptibility of TrxR1 for killing tumor cells. PMID:27377780

  16. Cognitive and cognitive-motor interventions affecting physical functioning: A systematic review

    PubMed Central

    2011-01-01

    Background Several types of cognitive or combined cognitive-motor intervention types that might influence physical functions have been proposed in the past: training of dual-tasking abilities, and improving cognitive function through behavioral interventions or the use of computer games. The objective of this systematic review was to examine the literature regarding the use of cognitive and cognitive-motor interventions to improve physical functioning in older adults or people with neurological impairments that are similar to cognitive impairments seen in aging. The aim was to identify potentially promising methods that might be used in future intervention type studies for older adults. Methods A systematic search was conducted for the Medline/Premedline, PsycINFO, CINAHL and EMBASE databases. The search was focused on older adults over the age of 65. To increase the number of articles for review, we also included those discussing adult patients with neurological impairments due to trauma, as these cognitive impairments are similar to those seen in the aging population. The search was restricted to English, German and French language literature without any limitation of publication date or restriction by study design. Cognitive or cognitive-motor interventions were defined as dual-tasking, virtual reality exercise, cognitive exercise, or a combination of these. Results 28 articles met our inclusion criteria. Three articles used an isolated cognitive rehabilitation intervention, seven articles used a dual-task intervention and 19 applied a computerized intervention. There is evidence to suggest that cognitive or motor-cognitive methods positively affects physical functioning, such as postural control, walking abilities and general functions of the upper and lower extremities, respectively. The majority of the included studies resulted in improvements of the assessed functional outcome measures. Conclusions The current evidence on the effectiveness of cognitive or

  17. Stable complex formation between HIV Rev and the nucleosome assembly protein, NAP1, affects Rev function

    SciTech Connect

    Cochrane, Alan; Murley, Laura Lea; Gao Mian; Wong, Raymond; Clayton, Kiera; Brufatto, Nicole; Canadien, Veronica; Mamelak, Daniel; Chen, Tricia; Richards, Dawn; Zeghouf, Mahel; Greenblatt, Jack; Burks, Christian; Frappier, Lori

    2009-05-25

    The Rev protein of HIV-1 is essential for HIV-1 proliferation due to its role in exporting viral RNA from the nucleus. We used a modified version of tandem affinity purification (TAP) tagging to identify proteins interacting with HIV-1 Rev in human cells and discovered a prominent interaction between Rev and nucleosome assembly protein 1 (Nap1). This interaction was also observed by specific retention of Nap1 from human cell lysates on a Rev affinity column. Nap1 was found to bind Rev through the Rev arginine-rich domain and altered the oligomerization state of Rev in vitro. Overexpression of Nap1 stimulated the ability of Rev to export RNA, reduced the nucleolar localization of Rev, and affected Rev nuclear import rates. The results suggest that Nap-1 may influence Rev function by increasing the availability of Rev.

  18. Metacognitive Awareness of Facial Affect in Higher-Functioning Children and Adolescents with Autism Spectrum Disorder.

    PubMed

    McMahon, Camilla M; Henderson, Heather A; Newell, Lisa; Jaime, Mark; Mundy, Peter

    2016-03-01

    Higher-functioning participants with and without autism spectrum disorder (ASD) viewed a series of face stimuli, made decisions regarding the affect of each face, and indicated their confidence in each decision. Confidence significantly predicted accuracy across all participants, but this relation was stronger for participants with typical development than participants with ASD. In the hierarchical linear modeling analysis, there were no differences in face processing accuracy between participants with and without ASD, but participants with ASD were more confident in their decisions. These results suggest that individuals with ASD have metacognitive impairments and are overconfident in face processing. Additionally, greater metacognitive awareness was predictive of better face processing accuracy, suggesting that metacognition may be a pivotal skill to teach in interventions. PMID:26496991

  19. How measurement artifacts affect cerebral autoregulation outcomes: A technical note on transfer function analysis.

    PubMed

    Meel-van den Abeelen, Aisha S S; de Jong, Daan L K; Lagro, Joep; Panerai, Ronney B; Claassen, Jurgen A H R

    2016-05-01

    Cerebral autoregulation (CA) is the mechanism that aims to maintain adequate cerebral perfusion during changes in blood pressure (BP). Transfer function analysis (TFA), the most reported method in literature to quantify CA, shows large between-study variability in outcomes. The aim of this study is to investigate the role of measurement artifacts in this variation. Specifically, the role of distortion in the BP and/or CBFV measurementon TFA outcomes was investigated. The influence of three types of artifacts on TFA outcomes was studied: loss of signal, motion artifacts, and baseline drifts. TFA metrics of signals without the simulated artifacts were compared with those of signals with artifacts. TFA outcomes scattered highly when more than 10% of BP signal or over 8% of the CBFV signal was lost, or when measurements contained one or more artifacts resulting from head movement. Furthermore, baseline drift affected interpretation of TFA outcomes when the power in the BP signal was 5 times the power in the LF band. In conclusion, loss of signal in BP and loss in CBFV, affects interpretation of TFA outcomes. Therefore, it is vital to validate signal quality to the defined standards before interpreting TFA outcomes. PMID:26935320

  20. Low-dose irradiation affects the functional behavior of oral microbiota in the context of mucositis.

    PubMed

    Vanhoecke, Barbara W A; De Ryck, Tine R G; De boel, Kevin; Wiles, Siouxsie; Boterberg, Tom; Van de Wiele, Tom; Swift, Simon

    2016-01-01

    The role of host-microbe interactions in the pathobiology of oral mucositis is still unclear; therefore, this study aimed to unravel the effect of irradiation on behavioral characteristics of oral microbial species in the context of mucositis. Using various experimental in vitro setups, the effects of irradiation on growth and biofilm formation of two Candida spp., Streptococcus salivarius and Klebsiella oxytoca in different culture conditions were evaluated. Irradiation did not affect growth of planktonic cells, but reduced the number of K. oxytoca cells in newly formed biofilms cultured in static conditions. Biofilm formation of K. oxytoca and Candida glabrata was affected by irradiation and depended on the culturing conditions. In the presence of mucins, these effects were lost, indicating the protective nature of mucins. Furthermore, the Galleria melonella model was used to study effects on microbial virulence. Irradiated K. oxytoca microbes were more virulent in G. melonella larvae compared to the nonirradiated ones. Our data indicate that low-dose irradiation can have an impact on functional characteristics of microbial species. Screening for pathogens like K. oxytoca in the context of mucosits could be useful to allow early detection and immediate intervention. PMID:26202372

  1. Sensory integration dysfunction affects efficacy of speech therapy on children with functional articulation disorders

    PubMed Central

    Tung, Li-Chen; Lin, Chin-Kai; Hsieh, Ching-Lin; Chen, Ching-Chi; Huang, Chin-Tsan; Wang, Chun-Hou

    2013-01-01

    Background Articulation disorders in young children are due to defects occurring at a certain stage in sensory and motor development. Some children with functional articulation disorders may also have sensory integration dysfunction (SID). We hypothesized that speech therapy would be less efficacious in children with SID than in those without SID. Hence, the purpose of this study was to compare the efficacy of speech therapy in two groups of children with functional articulation disorders: those without and those with SID. Method: A total of 30 young children with functional articulation disorders were divided into two groups, the no-SID group (15 children) and the SID group (15 children). The number of pronunciation mistakes was evaluated before and after speech therapy. Results: There were no statistically significant differences in age, sex, sibling order, education of parents, and pretest number of mistakes in pronunciation between the two groups (P > 0.05). The mean and standard deviation in the pre- and post-test number of mistakes in pronunciation were 10.5 ± 3.2 and 3.3 ± 3.3 in the no-SID group, and 10.1 ± 2.9 and 6.9 ± 3.5 in the SID group, respectively. Results showed great changes after speech therapy treatment (F = 70.393; P < 0.001) and interaction between the pre/post speech therapy treatment and groups (F = 11.119; P = 0.002). Conclusions: Speech therapy can improve the articulation performance of children who have functional articulation disorders whether or not they have SID, but it results in significantly greater improvement in children without SID. SID may affect the treatment efficiency of speech therapy in young children with articulation disorders. PMID:23355780

  2. Macrofauna assemblage composition and soil moisture interact to affect soil ecosystem functions

    NASA Astrophysics Data System (ADS)

    Collison, E. J.; Riutta, T.; Slade, E. M.

    2013-02-01

    Changing climatic conditions and habitat fragmentation are predicted to alter the soil moisture conditions of temperate forests. It is not well understood how the soil macrofauna community will respond to changes in soil moisture, and how changes to species diversity and community composition may affect ecosystem functions, such as litter decomposition and soil fluxes. Moreover, few studies have considered the interactions between the abiotic and biotic factors that regulate soil processes. Here we attempt to disentangle the interactive effects of two of the main factors that regulate soil processes at small scales - moisture and macrofauna assemblage composition. The response of assemblages of three common temperate soil invertebrates (Glomeris marginata Villers, Porcellio scaber Latreille and Philoscia muscorum Scopoli) to two contrasting soil moisture levels was examined in a series of laboratory mesocosm experiments. The contribution of the invertebrates to the leaf litter mass loss of two common temperate tree species of contrasting litter quality (easily decomposing Fraxinus excelsior L. and recalcitrant Quercus robur L.) and to soil CO2 fluxes were measured. Both moisture conditions and litter type influenced the functioning of the invertebrate assemblages, which was greater in high moisture conditions compared with low moisture conditions and on good quality vs. recalcitrant litter. In high moisture conditions, all macrofauna assemblages functioned at equal rates, whereas in low moisture conditions there were pronounced differences in litter mass loss among the assemblages. This indicates that species identity and assemblage composition are more important when moisture is limited. We suggest that complementarity between macrofauna species may mitigate the reduced functioning of some species, highlighting the importance of maintaining macrofauna species richness.

  3. Methyl donor deficiency affects small-intestinal differentiation and barrier function in rats.

    PubMed

    Bressenot, Aude; Pooya, Shabnam; Bossenmeyer-Pourie, Carine; Gauchotte, Guillaume; Germain, Adeline; Chevaux, Jean-Baptiste; Coste, Florence; Vignaud, Jean-Michel; Guéant, Jean-Louis; Peyrin-Biroulet, Laurent

    2013-02-28

    Dietary methyl donors and their genetic determinants are associated with Crohn's disease risk. We investigated whether a methyl-deficient diet (MDD) may affect development and functions of the small intestine in rat pups from dams subjected to the MDD during gestation and lactation. At 1 month before pregnancy, adult females were fed with either a standard food or a diet without vitamin B12, folate and choline. A global wall hypotrophy was observed in the distal small bowel (MDD animals 0·30 mm v. controls 0·58 mm; P< 0·001) with increased crypt apoptosis (3·37 v. 0·4%; P< 0·001), loss of enterocyte differentiation in the villus and a reduction in intestinal alkaline phosphatase production. Cleaved caspase-3 immunostaining (MDD animals 3·37% v. controls 0·4%, P< 0·001) and the Apostain labelling index showed increased crypt apoptosis (3·5 v. 1·4%; P= 0·018). Decreased proliferation was observed in crypts of the proximal small bowel with a reduced number of minichromosome maintenance 6 (MDD animals 52·83% v. controls 83·17%; P= 0·048) and proliferating cell nuclear antigen-positive cells (46·25 v. 59 %; P= 0·05). This lack of enterocyte differentiation in the distal small bowel was associated with an impaired expression of β-catenin and a decreased β-catenin-E-cadherin interaction. The MDD affected the intestinal barrier in the proximal small bowel by decreasing Paneth cell number after immunostaining for lysosyme (MDD animals 8·66% v. controls 21·66%) and by reducing goblet cell number and mucus production after immunostaining for mucin-2 (crypts 8·66 v. 15·33%; villus 7 v. 17%). The MDD has dual effects on the small intestine by producing dramatic effects on enterocyte differentiation and barrier function in rats. PMID:22794784

  4. Retrospective analysis of lung function abnormalities of Bhopal gas tragedy affected population

    PubMed Central

    De, Sajal

    2012-01-01

    Background & objectives: A large numbers of subjects were exposed to the aerosol of methyl isocyanate (MIC) during Bhopal gas disaster and lung was one of the most commonly affected organs. The aim of the present study was to analyze retrospectively the lung function abnormalities among the surviving MIC exposed population (gas victims) and to compare it with the non-MIC exposed (non gas exposed) population. Methods: The spirometry data of both gas victims and non gas exposed population who attended the Bhopal Memorial Hospital & Research Centre for evaluation of their respiratory complaints from August 2001 to December 2009, were retrospectively evaluated and compared. Results: A total 4782 gas victims and 1190 non gas exposed individuals performed spirometry during the study period. Among the gas victims, obstructive pattern was the commonest (50.8%) spirometric abnormality followed by restrictive pattern (13.3%). The increased relative risk of developing restrictive abnormality among gas victims was observed in 20-29 yr age group only (adjusted relative risk: 2.94, P<0.001). Male gas victims were more affected by severe airflow obstruction than females and the overall increased relative risk (1.33 to 1.45, P<0.001) of developing obstructive pattern among gas victims was observed. Interpretation & conclusions: The present study showed that the relative risk for pulmonary function abnormalities in gas victims was significantly more among those who were young at the time of disaster. Increased smoking habit among gas victims might have played an additive effect on predominance of obstructive pattern in spirometry. PMID:22446861

  5. Chronic Exposure to Bisphenol A Affects Uterine Function During Early Pregnancy in Mice.

    PubMed

    Li, Quanxi; Davila, Juanmahel; Kannan, Athilakshmi; Flaws, Jodi A; Bagchi, Milan K; Bagchi, Indrani C

    2016-05-01

    Environmental and occupational exposure to bisphenol A (BPA), a chemical widely used in polycarbonate plastics and epoxy resins, has received much attention in female reproductive health due to its widespread toxic effects. Although BPA has been linked to infertility and recurrent miscarriage in women, the impact of its exposure on uterine function during early pregnancy remains unclear. In this study, we addressed the effect of prolonged exposure to an environmental relevant dose of BPA on embryo implantation and establishment of pregnancy. Our studies revealed that treatment of mice with BPA led to improper endometrial epithelial and stromal functions thus affecting embryo implantation and establishment of pregnancy. Upon further analyses, we found that the expression of progesterone receptor (PGR) and its downstream target gene, HAND2 (heart and neural crest derivatives expressed 2), was markedly suppressed in BPA-exposed uterine tissues. Previous studies have shown that HAND2 controls embryo implantation by repressing fibroblast growth factor and the MAPK signaling pathways and inhibiting epithelial proliferation. Interestingly, we observed that down-regulation of PGR and HAND2 expression in uterine stroma upon BPA exposure was associated with enhanced activation of fibroblast growth factor and MAPK signaling in the epithelium, thus contributing to aberrant proliferation and lack of uterine receptivity. Further, the differentiation of endometrial stromal cells to decidual cells, an event critical for the establishment and maintenance of pregnancy, was severely compromised in response to BPA. In summary, our studies revealed that chronic exposure to BPA impairs PGR-HAND2 pathway and adversely affects implantation and the establishment of pregnancy. PMID:27022677

  6. Behavioral Functions of the Mesolimbic Dopaminergic System: an Affective Neuroethological Perspective

    PubMed Central

    Alcaro, Antonio; Huber, Robert; Panksepp, Jaak

    2008-01-01

    The mesolimbic dopaminergic (ML-DA) system has been recognized for its central role in motivated behaviors, various types of reward, and, more recently, in cognitive processes. Functional theories have emphasized DA's involvement in the orchestration of goal-directed behaviors, and in the promotion and reinforcement of learning. The affective neuroethological perspective presented here, views the ML-DA system in terms of its ability to activate an instinctual emotional appetitive state (SEEKING) evolved to induce organisms to search for all varieties of life-supporting stimuli and to avoid harms. A description of the anatomical framework in which the ML system is embedded is followed by the argument that the SEEKING disposition emerges through functional integration of ventral basal ganglia (BG) into thalamocortical activities. Filtering cortical and limbic input that spread into BG, DA transmission promotes the “release” of neural activity patterns that induce active SEEKING behaviors when expressed at the motor level. Reverberation of these patterns constitutes a neurodynamic process for the inclusion of cognitive and perceptual representations within the extended networks of the SEEKING urge. In this way, the SEEKING disposition influences attention, incentive salience, associative learning, and anticipatory predictions. In our view, the rewarding properties of drugs of abuse are, in part, caused by the activation of the SEEKING disposition, ranging from appetitive drive to persistent craving depending on the intensity of the affect. The implications of such a view for understanding addiction are considered, with particular emphasis on factors predisposing individuals to develop compulsive drug seeking behaviors. PMID:17905440

  7. Cellular imaging using biocompatible dendrimer-functionalized graphene oxide-based fluorescent probe anchored with magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Wate, Prateek S.; Banerjee, Shashwat S.; Jalota-Badhwar, Archana; Mascarenhas, Russel R.; Zope, Khushbu R.; Khandare, Jayant; Misra, R. Devesh K.

    2012-10-01

    We describe a novel multicomponent graphene nanostructured system that is biocompatible, and has strong NIR optical absorbance and superparamagnetic properties. The fabrication of the multicomponent nanostructure system involves the covalent attachment of 3 components; Fe3O4(Fe) nanoparticles, PAMAM-G4-NH2 (G4) dendrimer and Cy5 (Cy) on a graphene oxide (GO) surface to synthesize a biologically relevant multifunctional system. The resultant GO-G4-Fe-Cy nanosystem exhibits high dispersion in an aqueous medium, and is magnetically responsive and fluorescent. In vitro experiments provide a clear indication of successful uptake of the GO-G4-Fe-Cy nanosystem by MCF-7 breast cancer cells, and it is seen to behave as a bright and stable fluorescent marker. The study also reveals varied cellular distribution kinetics profile for the GO nanostructured system compared to free Cy. Furthermore, the newly developed GO nanostructured system is observed to be non-toxic to MDA-MB-231 cell growth, in striking contrast to free G4 dendrimer and GO-G4 conjugate. The GO-G4-Fe-Cy nanostructured system characterized by multifunctionality suggests the merits of graphene for cellular bioimaging and the delivery of bioactives.

  8. The aprosodias: further functional-anatomical evidence for the organisation of affective language in the right hemisphere.

    PubMed Central

    Gorelick, P B; Ross, E D

    1987-01-01

    Fourteen right-handed patients with right hemispheric strokes were examined for disorders of affective language in order to further define the clinical-anatomical correlates of the aprosodias. A bedside evaluation strategy and CT scan mappings were utilised to make these comparisons. There were six patients with motor aprosodia, one with global aprosodia, two with conduction aprosodia, one with sensory aprosodia, one with transcortical sensory aprosodia, one with pure affective deafness and two with normal examinations of affect. Functional-anatomical correlations were consistent with those predicted previously. Recovery of affective language function in selected cases was characterised by improvements in affective-prosodic repetition and/or evolution into other aprosodic subtypes. Our results lend further support to the hypothesis that the organisation of affective language in the right hemisphere mirrors that of propositional language in the left hemisphere. Images PMID:2438386

  9. Genetic Dominance & Cellular Processes

    ERIC Educational Resources Information Center

    Seager, Robert D.

    2014-01-01

    In learning genetics, many students misunderstand and misinterpret what "dominance" means. Understanding is easier if students realize that dominance is not a mechanism, but rather a consequence of underlying cellular processes. For example, metabolic pathways are often little affected by changes in enzyme concentration. This means that…

  10. Systematic Functional Dissection of Common Genetic Variation Affecting Red Blood Cell Traits.

    PubMed

    Ulirsch, Jacob C; Nandakumar, Satish K; Wang, Li; Giani, Felix C; Zhang, Xiaolan; Rogov, Peter; Melnikov, Alexandre; McDonel, Patrick; Do, Ron; Mikkelsen, Tarjei S; Sankaran, Vijay G

    2016-06-01

    Genome-wide association studies (GWAS) have successfully identified thousands of associations between common genetic variants and human disease phenotypes, but the majority of these variants are non-coding, often requiring genetic fine-mapping, epigenomic profiling, and individual reporter assays to delineate potential causal variants. We employ a massively parallel reporter assay (MPRA) to simultaneously screen 2,756 variants in strong linkage disequilibrium with 75 sentinel variants associated with red blood cell traits. We show that this assay identifies elements with endogenous erythroid regulatory activity. Across 23 sentinel variants, we conservatively identified 32 MPRA functional variants (MFVs). We used targeted genome editing to demonstrate endogenous enhancer activity across 3 MFVs that predominantly affect the transcription of SMIM1, RBM38, and CD164. Functional follow-up of RBM38 delineates a key role for this gene in the alternative splicing program occurring during terminal erythropoiesis. Finally, we provide evidence for how common GWAS-nominated variants can disrupt cell-type-specific transcriptional regulatory pathways. PMID:27259154

  11. Histopathology of growth anomaly affecting the coral, Montipora capitata: implications on biological functions and population viability.

    PubMed

    Burns, John H R; Takabayashi, Misaki

    2011-01-01

    Growth anomalies (GAs) affect the coral, Montipora capitata, at Wai'ōpae, southeast Hawai'i Island. Our histopathological analysis of this disease revealed that the GA tissue undergoes changes which compromise anatomical machinery for biological functions such as defense, feeding, digestion, and reproduction. GA tissue exhibited significant reductions in density of ova (66.1-93.7%), symbiotic dinoflagellates (38.8-67.5%), mesenterial filaments (11.2-29.0%), and nematocytes (28.8-46.0%). Hyperplasia of the basal body wall but no abnormal levels of necrosis and algal or fungal invasion was found in GA tissue. Skeletal density along the basal body wall was significantly reduced in GAs compared to healthy or unaffected sections. The reductions in density of the above histological features in GA tissue were collated with disease severity data to quantify the impact of this disease at the colony and population level. Resulting calculations showed this disease reduces the fecundity of M. capitata colonies at Wai'ōpae by 0.7-49.6%, depending on GA severity, and the overall population fecundity by 2.41±0.29%. In sum, GA in this M. capitata population reduces the coral's critical biological functions and increases susceptibility to erosion, clearly defining itself as a disease and an ecological threat. PMID:22205976

  12. Nongenetic functions of the genome.

    PubMed

    Bustin, Michael; Misteli, Tom

    2016-05-01

    The primary function of the genome is to store, propagate, and express the genetic information that gives rise to a cell's architectural and functional machinery. However, the genome is also a major structural component of the cell. Besides its genetic roles, the genome affects cellular functions by nongenetic means through its physical and structural properties, particularly by exerting mechanical forces and by serving as a scaffold for binding of cellular components. Major cellular processes affected by nongenetic functions of the genome include establishment of nuclear structure, signal transduction, mechanoresponses, cell migration, and vision in nocturnal animals. We discuss the concept, mechanisms, and implications of nongenetic functions of the genome. PMID:27151873

  13. Functional interaction between the human cytomegalovirus 86-kilodalton IE2 protein and the cellular transcription factor CREB.

    PubMed Central

    Lang, D; Gebert, S; Arlt, H; Stamminger, T

    1995-01-01

    The 86-kDa IE2 protein (IE86) of human cytomegalovirus (HCMV) has been described as a promiscuous transactivator of viral, as well as cellular, gene expression. Investigation of the mechanism used by IE86 to activate gene expression from the early UL112/113 promoter of HCMV revealed the existence of three binding sites for IE86 located between nucleotides -290 and -120 relative to the transcriptional start site (H. Arlt, D. Lang, S. Gebert, and T. Stamminger, J. Virol. 68:4117-4125, 1994). As shown previously, deletion of these target sites resulted in a reduction of IE86-mediated transactivation by approximately 70%. The remaining promoter, however, could still be stimulated about 40-fold, indicating the presence of an additional responsive element within these sequences. Here, we provide evidence that a binding site for the cellular transcription factor CREB can also act as a target for IE86 transactivation. By DNase I protection analysis, a binding sequence for CREB could be detected between nucleotides -78 and -56 within the respective promoter region. After in vitro mutagenesis of this CREB-binding site within the context of the entire UL112/113 promoter, a marked reduction in transactivation levels was evident. Moreover, when individual CREB-binding sites were positioned upstream of a minimal, TATA box-containing UL112/113 promoter, they were able to confer strong IE86 responsiveness, whereas a mutated sequence did not exert any effect. In far Western blot and pull-down experiments, a direct interaction of IE86 with the cellular transcription factor CREB could be observed. The in vivo relevance of this in vitro interaction was confirmed by using various GAL4 fusion proteins in the presence or absence of IE86 which revealed a strong activation only in the presence of both a GAL4-CREB fusion and IE86. This shows that at least one specific member of the ATF/CREB family of transcription factors is involved in mediating transactivation by the HCMV IE86 protein

  14. Selexipag: a selective prostacyclin receptor agonist that does not affect rat gastric function.

    PubMed

    Morrison, Keith; Ernst, Roland; Hess, Patrick; Studer, Rolf; Clozel, Martine

    2010-10-01

    Selexipag [2-{4-[(5,6-diphenylpyrazin-2-yl)(isopropyl)amino]butoxy}-N-(methylsulfonyl)acetamide] is an orally available prostacyclin (PGI(2)) receptor (IP receptor) agonist that is chemically distinct from PGI(2) and is in clinical development for the treatment of pulmonary arterial hypertension. Selexipag is highly selective for the human IP receptor in vitro, whereas analogs of PGI(2) can activate prostanoid receptors other than the IP receptor. The goal of this study was to determine the impact of selectivity for the IP receptor on gastric function by measuring 1) contraction of rat gastric fundus ex vivo and 2) the rates of gastric emptying and intestinal transport in response to selexipag in comparison with other PGI(2) analogs. The rat gastric fundus expresses mRNA encoding multiple prostanoid receptors to different levels: prostaglandin E receptor 1 (EP(1)) > prostaglandin E receptor 3 (EP(3)), IP receptor > prostaglandin D(2) receptor 1, thromboxane receptor. Selexipag and metabolite {4-[(5,6-diphenylpyrazin-2-yl)(isopropyl)amino]butoxy}acetic acid (ACT-333679) did not contract gastric fundus at concentrations up to 10(-3) M. In contrast, the PGI(2) analogs iloprost and beraprost evoked concentration-dependent contraction of gastric fundus. Contraction to treprostinil was observed at high concentration (10(-4) M). Contraction to all PGI(2) analogs was mediated via activation of EP(3) receptors, although EP(1) receptors also contributed to the contraction of gastric fundus to iloprost and beraprost. Antagonism of IP receptors did not affect responses. Oral selexipag did not significantly alter gastric function in vivo, as measured by rates of stomach emptying and intestinal transport, whereas beraprost slowed gastrointestinal transport. The high functional selectivity of selexipag and ACT-333679 for the IP receptor precludes a stimulatory action on gastric smooth muscle and may help minimize gastric side effects such as nausea and vomiting. PMID:20660124

  15. Key soil functional properties affected by soil organic matter - evidence from published literature

    NASA Astrophysics Data System (ADS)

    Murphy, Brian

    2015-07-01

    The effect of varying the amount of soil organic matter on a range of individual soil properties was investigated using a literature search of published information largely from Australia, but also included relevant information from overseas. Based on published pedotransfer functions, soil organic matter was shown to increase plant available water by 2 to 3 mm per 10 cm for each 1% increase in soil organic carbon, with the largest increases being associated with sandy soils. Aggregate stability increased with increasing soil organic carbon, with aggregate stability decreasing rapidly when soil organic carbon fell below 1.2 to 1.5 5%. Soil compactibility, friability and soil erodibility were favourably improved by increasing the levels of soil organic carbon. Nutrient cycling was a major function of soil organic matter. Substantial amounts of N, P and S become available to plants when the soil organic matter is mineralised. Soil organic matter also provides a food source for the microorganisms involved in the nutrient cycling of N, P, S and K. In soils with lower clay contents, and less active clays such as kaolinites, soil organic matter can supply a significant amount of the cation exchange capacity and buffering capacity against acidification. Soil organic matter can have a cation exchange capacity of 172 to 297 cmol(+)/kg. As the cation exchange capacity of soil organic matter varies with pH, the effectiveness of soil organic matter to contribute to cation exchange capacity below pH 5.5 is often minimal. Overall soil organic matter has the potential to affect a range of functional soil properties.

  16. PARP1 Gene Knock-Out Increases Resistance to Retinal Degeneration without Affecting Retinal Function

    PubMed Central

    Sahaboglu, Ayse; Tanimoto, Naoyuki; Kaur, Jasvir; Sancho-Pelluz, Javier; Huber, Gesine; Fahl, Edda; Arango-Gonzalez, Blanca; Zrenner, Eberhart; Ekström, Per; Löwenheim, Hubert; Seeliger, Mathias; Paquet-Durand, François

    2010-01-01

    Retinitis pigmentosa (RP) is a group of inherited neurodegenerative diseases affecting photoreceptors and causing blindness in humans. Previously, excessive activation of enzymes belonging to the poly-ADP-ribose polymerase (PARP) group was shown to be involved in photoreceptor degeneration in the human homologous rd1 mouse model for RP. Since there are at least 16 different PARP isoforms, we investigated the exact relevance of the predominant isoform - PARP1 - for photoreceptor cell death using PARP1 knock-out (KO) mice. In vivo and ex vivo morphological analysis using optic coherence tomography (OCT) and conventional histology revealed no major alterations of retinal phenotype when compared to wild-type (wt). Likewise, retinal function as assessed by electroretinography (ERG) was normal in PARP1 KO animals. We then used retinal explant cultures derived from wt, rd1, and PARP1 KO animals to test their susceptibility to chemically induced photoreceptor degeneration. Since photoreceptor degeneration in the rd1 retina is triggered by a loss-of-function in phosphodiesterase-6 (PDE6), we used selective PDE6 inhibition to emulate the rd1 situation on non-rd1 genotypes. While wt retina subjected to PDE6 inhibition showed massive photoreceptor degeneration comparable to rd1 retina, in the PARP1 KO situation, cell death was robustly reduced. Together, these findings demonstrate that PARP1 activity is in principle dispensable for normal retinal function, but is of major importance for photoreceptor degeneration under pathological conditions. Moreover, our results suggest that PARP dependent cell death or PARthanatos may play a major role in retinal degeneration and highlight the possibility to use specific PARP inhibitors for the treatment of RP. PMID:21124852

  17. A New Flow-Regulating Cell Type in the Demosponge Tethya wilhelma – Functional Cellular Anatomy of a Leuconoid Canal System

    PubMed Central

    Hammel, Jörg U.; Nickel, Michael

    2014-01-01

    Demosponges possess a leucon-type canal system which is characterized by a highly complex network of canal segments and choanocyte chambers. As sponges are sessile filter feeders, their aquiferous system plays an essential role in various fundamental physiological processes. Due to the morphological and architectural complexity of the canal system and the strong interdependence between flow conditions and anatomy, our understanding of fluid dynamics throughout leuconoid systems is patchy. This paper provides comprehensive morphometric data on the general architecture of the canal system, flow measurements and detailed cellular anatomical information to help fill in the gaps. We focus on the functional cellular anatomy of the aquiferous system and discuss all relevant cell types in the context of hydrodynamic and evolutionary constraints. Our analysis is based on the canal system of the tropical demosponge Tethya wilhelma, which we studied using scanning electron microscopy. We found a hitherto undescribed cell type, the reticuloapopylocyte, which is involved in flow regulation in the choanocyte chambers. It has a highly fenestrated, grid-like morphology and covers the apopylar opening. The minute opening of the reticuloapopylocyte occurs in an opened, intermediate and closed state. These states permit a gradual regulation of the total apopylar opening area. In this paper the three states are included in a theoretical study into flow conditions which aims to draw a link between functional cellular anatomy, the hydrodynamic situation and the regular body contractions seen in T. wilhelma. This provides a basis for new hypotheses regarding the function of bypass elements and the role of hydrostatic pressure in body contractions. Our study provides insights into the local and global flow conditions in the sponge canal system and thus enhances current understanding of related physiological processes. PMID:25409176

  18. Functional Anthology of Intrinsic Disorder. II. Cellular Components, Domains, Technical Terms, Developmental Processes and Coding Sequence Diversities Correlated with Long Disordered Regions

    PubMed Central

    Vucetic, Slobodan; Xie, Hongbo; Iakoucheva, Lilia M.; Oldfield, Christopher J.; Dunker, A. Keith; Obradovic, Zoran; Uversky, Vladimir N.

    2008-01-01

    Biologically active proteins without stable ordered structure (i.e., intrinsically disordered proteins) are attracting increased attention. Functional repertoires of ordered and disordered proteins are very different, and the ability to differentiate whether a given function is associated with intrinsic disorder or with a well-folded protein is crucial for modern protein science. However, there is a large gap between the number of proteins experimentally confirmed to be disordered and their actual number in nature. As a result, studies of functional properties of confirmed disordered proteins, while helpful in revealing the functional diversity of protein disorder, provide only a limited view. To overcome this problem, a bioinformatics approach for comprehensive study of functional roles of protein disorder was proposed in the first paper of this series (Xie H., Vucetic S., Iakoucheva L.M., Oldfield C.J., Dunker A.K., Obradovic Z., Uversky V.N. (2006) Functional anthology of intrinsic disorder. I. Biological processes and functions of proteins with long disordered regions. J. Proteome Res.). Applying this novel approach to Swiss-Prot sequences and functional keywords, we found over 238 and 302 keywords to be strongly positively or negatively correlated, respectively, with long intrinsically disordered regions. This paper describes ~90 Swiss-Prot keywords attributed to the cellular components, domains, technical terms, developmental processes and coding sequence diversities possessing strong positive and negative correlation with long disordered regions. PMID:17391015

  19. Dual Functional Nanocarrier for Cellular Imaging and Drug Delivery in Cancer Cells Based on π-Conjugated Core and Biodegradable Polymer Arms.

    PubMed

    Kulkarni, Bhagyashree; Surnar, Bapurao; Jayakannan, Manickam

    2016-03-14

    Multipurpose polymer nanoscaffolds for cellular imaging and delivery of anticancer drug are urgently required for the cancer therapy. The present investigation reports a new polymer drug delivery concept based on biodegradable polycaprolactone (PCL) and highly luminescent π-conjugated fluorophore as dual functional nanocarrier for cellular imaging and delivery vehicles for anticancer drug to cancer cells. To accomplish this goal, a new substituted caprolactone monomer was designed, and it was subjected to ring opening polymerization using a blue luminescent bishydroxyloligo-phenylenevinylene (OPV) fluorophore as an initiator. A series of A-B-A triblock copolymer building blocks with a fixed OPV π-core and variable chain biodegradable PCL arm length were tailor-made. These triblocks self-assembled in organic solvents to produce well-defined helical nanofibers, whereas in water they produced spherical nanoparticles (size ∼150 nm) with blue luminescence. The hydrophobic pocket of the polymer nanoparticle was found to be an efficient host for loading water insoluble anticancer drug such as doxorubicin (DOX). The photophysical studies revealed that there was no cross-talking between the OPV and DOX chromophores, and their optical purity was retained in the nanoparticle assembly for cellular imaging. In vitro studies revealed that the biodegradable PCL arm was susceptible to enzymatic cleavage at the intracellular lysosomal esterase under physiological conditions to release the loaded drugs. The nascent nanoparticles were found to be nontoxic to cancer cells, whereas the DOX-loaded nanoparticles accomplished more than 80% killing in HeLa cells. Confocal microscopic analysis confirmed the cell penetrating ability of the blue luminescent polymer nanoparticles and their accumulation preferably in the cytoplasm. The DOX loaded red luminescent polymer nanoparticles were also taken up by the cells, and the drug was found to be accumulated at the perinuclear environment

  20. Hydrogen peroxide sensors for cellular imaging based on horse radish peroxidase reconstituted on polymer-functionalized TiO2 nanorods

    NASA Astrophysics Data System (ADS)

    Tahir, Muhammad Nawaz; André, Rute; Sahoo, Jugal Kishore; Jochum, Florian D.; Theato, Patrick; Natalio, Filipe; Berger, Rüdiger; Branscheid, Robert; Kolb, Ute; Tremel, Wolfgang

    2011-09-01

    We describe the reconstitution of apo-horse radish peroxidase (apo-HRP) onto TiO2 nanorods functionalized with a multifunctional polymer. After functionalization, the horse radish peroxidase (HRP) functionalized TiO2 nanorods were well dispersible in aqueous solution, catalytically active and biocompatible, and they could be used to quantify and image H2O2 which is a harmful secondary product of cellular metabolism. The shape, size and structure of TiO2 nanorods (anatase) were analyzed by transmission electron microscopy (TEM), high resolution TEM (HRTEM), electron diffraction (ED) and X-ray diffraction (XRD). The surface functionalization, HRP reconstitution and catalytic activity were confirmed by UV-Vis, FT-IR, CLSM and atomic force microscopy (AFM). Biocompatibility and cellular internalization of active HRP reconstituted TiO2 nanorods were confirmed by a classical MTT cytotoxicity assay and confocal laser scanning microscopy (CLSM) imaging, respectively. The intracellular localization allowed H2O2 detection, imaging and quantification in HeLa cells. The polymer functionalized hybrid system creates a complete sensor including a ``cell positioning system'' in each single particle. The flexible synthetic concept with functionalization by post-polymerization modification allows introduction of various dyes for sensitisation at different wavelengths and introduction of various anchor groups for anchoring on different particles.We describe the reconstitution of apo-horse radish peroxidase (apo-HRP) onto TiO2 nanorods functionalized with a multifunctional polymer. After functionalization, the horse radish peroxidase (HRP) functionalized TiO2 nanorods were well dispersible in aqueous solution, catalytically active and biocompatible, and they could be used to quantify and image H2O2 which is a harmful secondary product of cellular metabolism. The shape, size and structure of TiO2 nanorods (anatase) were analyzed by transmission electron microscopy (TEM), high