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1

Virus-like particles from rabbit hemorrhagic disease virus can induce an anti-tumor response  

Microsoft Academic Search

Recombinant virus-like particles (VLP) expressing heterologous tumor antigens have recently been investigated for use as vaccines. We have chemically conjugated ovalbumin (OVA) or OVA-derived CD4 (OTII) and CD8 (OTI) epitopes, to rabbit hemorrhagic disease virus (RHDV) VLP. VLP conjugated with OVA were able to cross-prime CD8+ cells from OT1 mice transgenic for the OVA T cell receptor. VLP.OTI was able

Matthew Peacey; Sarah Wilson; Rachel Perret; Franca Ronchese; Vernon K. Ward; Vivienne Young; Sarah L. Young; Margaret A. Baird

2008-01-01

2

Total revision of the hip using allograft to correct particle disease induced osteolysis: A case study  

Microsoft Academic Search

Total hip replacement is considered to be a highly successful and routine surgery; however, the internal components produce particles through friction and wear in the device. These particles are identified as one of the main reasons for total hip revisions. The generated, biologically active, particles provoke the formation of osteolytic areas through the inhibition of bone formation and increased fluid

Drew W. Taylor; Jennifer E. Taylor; Igal Raizman; Allan E. Gross

3

Total revision of the hip using allograft to correct particle disease induced osteolysis: a case study.  

PubMed

Total hip replacement is considered to be a highly successful and routine surgery; however, the internal components produce particles through friction and wear in the device. These particles are identified as one of the main reasons for total hip revisions. The generated, biologically active, particles provoke the formation of osteolytic areas through the inhibition of bone formation and increased fluid production. The resulting bone loss can be managed through the use of allograft bone in combination with bone chips and cement. In addition, implants constructed with highly porous trabecular metal can be used to further facilitate rapid and extensive tissue infiltration resulting in strong implant attachment. In this case study we show the use of a tibial allograft coupled with bone chips and cement to cover and support a lytic cyst in the proximal femur, distal to the greater trochanter. Additionally, we detail the use of a trabecular metal cup to halt the migration of the component into the acetabulum and promote greater fixation and bone ingrowth. PMID:19753282

Taylor, Drew W; Taylor, Jennifer E; Raizman, Igal; Gross, Allan E

2009-01-01

4

Newcastle disease virus-like particles containing respiratory syncytial virus G protein induced protection in BALB/c mice, with no evidence of immunopathology.  

PubMed

Respiratory syncytial virus (RSV) is the leading cause of serious respiratory infections in children as well as a serious cause of disease in elderly and immunosuppressed populations. There are no licensed vaccines available to prevent RSV disease. We have developed a virus-like particle (VLP) vaccine candidate for protection from RSV. The VLP is composed of the NP and M proteins of Newcastle disease virus (NDV) and a chimeric protein containing the cytoplasmic and transmembrane domains of the NDV HN protein and the ectodomain of the human RSV G protein (H/G). Immunization of mice with 10 or 40 microg total VLP-H/G protein by intraperitoneal or intramuscular inoculation stimulated antibody responses to G protein which were as good as or better than those stimulated by comparable amounts of UV-inactivated RSV. Immunization of mice with two doses or even a single dose of these particles resulted in the complete protection of mice from RSV replication in the lungs. Immunization with these particles induced neutralizing antibodies with modest titers. Upon RSV challenge of VLP-H/G-immunized mice, no enhanced pathology in the lungs was observed, although lungs of mice immunized in parallel with formalin-inactivated RSV (FI-RSV) showed the significant pathology that has previously been documented after immunization with FI-RSV. Thus, the VLP-H/G candidate vaccine was immunogenic in BALB/c mice and prevented replication of RSV in murine lungs, with no evidence of immunopathology. These data support further development of virus-like particle vaccine candidates for protection against RSV. PMID:19889768

Murawski, Matthew R; McGinnes, Lori W; Finberg, Robert W; Kurt-Jones, Evelyn A; Massare, Michael J; Smith, Gale; Heaton, Penny M; Fraire, Armando E; Morrison, Trudy G

2010-01-01

5

Drug-induced pulmonary disease  

MedlinePLUS

Drug-induced pulmonary disease is lung disease brought on by a bad reaction to a medicine. ... Maldonado F, Limper AH. Drug-induced pulmonary disease. In: Mason RJ, ... of Respiratory Medicine . 5th ed. Philadelphia, PA: Elsevier ...

6

[Gluten induced diseases].  

PubMed

The introduction of cereals in human nutrition 10 000 years ago caused the occurrence of gluten induced diseases. This protein complex is involved in pathogenesis of wheat allergy, celiac disease, and gluten sensitivity. Wheat allergy and celiac disease are mediated by the system of adaptive immunity. Gluten sensitivity is a recently defined entity induced by innate immune mechanisms. These subjects present various intestinal and particularly extraintestinal symptoms. The differences between celiac disease and gluten intolerance include permeability of the intestinal mucosal barrier, histology of duodenal biopsy, and mucosal gene expression. The symptoms of gluten sensitivity may also have another genetic background of food intolerance independent of the HLADQ2, -?DQ8 system and tissue transglutaminase (eg. in some psychiatric disorders). At present, there is no specific bio-marker of gluten sensitivity. The diagnosis is possible only by exclusion of other causes of symptoms and improvement on a glutenfree diet applied in a doubleblind placebo controlled manner with optional sequence of both stages to exclude the placebo effect due to nutritional intervention. PMID:23767452

Fri?, P; Zavoral, M; Dvo?áková, T

2013-05-01

7

Rosmarinic acid inhibits lung injury induced by diesel exhaust particles  

Microsoft Academic Search

Epidemiological and experimental studies have suggested that diesel exhaust particles (DEP) may be involved in recent increases in lung diseases. DEP has been shown to generate reactive oxygen species. Intratracheal instillation of DEP induces lung inflammation and edema in mice. Rosmarinic acid is a naturally occurring polyphenol with antioxidative and anti-inflammatory activities. We investigated the effects of rosmarinic acid on

Chiaki Sanbongi; Hirohisa Takano; Naomi Osakabe; Naoko Sasa; Midori Natsume; Rie Yanagisawa; Ken-ichiro Inoue; Yoji Kato; Toshihiko Osawa; Toshikazu Yoshikawa

2003-01-01

8

Energetic-particle-induced geodesic acoustic mode.  

PubMed

A new energetic particle-induced geodesic acoustic mode (EGAM) is shown to exist. The mode frequency and mode structure are determined nonperturbatively by energetic particle kinetic effects. In particular the EGAM frequency is found to be substantially lower than the standard GAM frequency. The radial mode width is determined by the energetic particle drift orbit width and can be fairly large for high energetic particle pressure and large safety factor. These results are consistent with the recent experimental observation of the beam-driven n=0 mode in DIII-D. PMID:18999836

Fu, G Y

2008-10-31

9

Oxidative stress and changed gene expression profiles in fiber-\\/particle-induced carcinogenesis  

Microsoft Academic Search

KEYWORDS Fibers; metals; gene expression; oxidative stress; cancer ABSTRACT Exposure to ambient air pollution (particles, fibres) is associated with pulmonary diseases and cancer. The mechanisms of induced health effects are believed to involve inflammation and oxidative stress. Oxidative stress mediated by airborne particles and\\/or fibres may arise from direct generation of reactive oxygen species (ROS) from the surface of particles\\/fibres,

Kunal Bhattacharya; Gerrit Alink; Elke Dopp

2007-01-01

10

Asbestos-induced lung disease.  

PubMed Central

This review attempts to deal with two major questions concerning asbestos-induced lung disease: How does inhaled asbestos cause cell proliferation and fibrosis? and Will there continue to be risk from exposure to asbestos in schools and public buildings? The first is a scientific question that has spawned many interesting new experiments over the past 10 years, and there appear to be two hypothetical schemes which could explain, at least in part, the fibroproliferative effects of asbestos fibers. One supports the view that toxic oxygen radicals generated on fiber surfaces and/or intracellularly are the central mediators of disease. The second hypothesis is not mutually exclusive of the first, but, in my opinion, may be integral to it, i.e., the cellular injury induced by oxygen radicals stimulates the elaboration of multiple varieties of growth factors and cytokines that mediate the pathogenesis of asbestosis. There is increasing evidence that molecules such as platelet-derived growth factor and transforming growth factor beta, both synthesized and secreted by activated lung macrophages, are responsible, respectively, for the increased interstitial cell populations and extracellular matrix proteins that are the hallmarks of asbestos-induced fibrosis. The challenge today is to establish which combinations of the many factors released actually are playing a role in disease pathogenesis. The issue of continued risk currently is more a question of policy and perception than science because a sufficient database has not yet been established to allow full knowledge of the circumstances under which asbestos in buildings constitutes an ongoing health hazard. The litigious nature of this question does not help its resolution. In as much as public policy statements and risk assessment are not within my purview, I have focused on the state-of-the-art of asbestos as a complete carcinogen. It appears to be generally nongenotoxic, but all asbestos fiber types can induce chromosomal mutations and aneuploidy, perhaps through their ability to disrupt normal chromosome segregation. Images FIGURE 1. 1a FIGURE 1. 1b FIGURE 2. FIGURE 3. FIGURE 4. 4a FIGURE 4. 4b FIGURE 5. 5a FIGURE 5. 5b FIGURE 6. PMID:8354168

Brody, A R

1993-01-01

11

Oestrogen deficiency modulates particle-induced osteolysis  

PubMed Central

Introduction Postmenopausal osteoporosis may modulate bone response to wear debris. In this article, we evaluate the influence of oestrogen deficiency on experimental particle-induced osteolysis. Methods Polyethylene (PE) particles were implanted onto the calvaria of normal controls, sham-ovariectomized (OVX), OVX mice and OVX mice supplemented with oestrogen (OVX+E). After 14 days, seven skulls per group were analyzed using a high-resolution micro-computed tomography (micro-CT) and histomorphometry, and for tartrate-specific alkaline phosphatase. Five calvariae per group were cultured for the assay of IL-1?, IL-6, TNF-? and receptor activator of the nuclear factor ?B (RANKL) secretion using quantitative ELISA. Serum IL-6 concentrations were obtained. The expression of RANKL and osteoprotegerin (OPG) mRNA were evaluated using real-time PCR. Results As assessed by ?CT and by histomorphometry, PE particles induced extensive bone resorption and an intense inflammatory reaction in normal controls, sham-OVX and OVX+E mice, but not in the OVX mice group. In normal controls, sham-OVX and OVX+E mice, PE particles induced an increase in serum IL-6, in TNF-? and RANKL local concentrations, and resulted in a significant increase in RANKL/OPG messenger RNA (mRNA) ratio. Conversely, these parameters remained unchanged in OVX mice after PE implantation. Conclusions Oestrogen privation in the osteolysis murine model ultimately attenuated osteolytic response to PE particles, suggesting a protective effect. This paradoxical phenomenon was associated with a down-regulation of pro-resorptive cytokines. It is hypothesized that excessive inflammatory response was controlled, illustrated by the absence of increase of serum IL-6 in OVX mice after PE implantation. PMID:21696618

2011-01-01

12

Particle production in antiproton induced nuclear reactions  

E-print Network

The quantum molecular dynamics model has been improved to investigate the reaction dynamics induced by antiprotons. The reaction channels of elastic scattering, annihilation, charge exchange and inelastic collisions have been included in the model. Dynamics on particle production, in particular pions, kaons, antikaons and hyperons, is investigated in collisions of $\\overline{p}$ on $^{12}$C, $^{20}$Ne, $^{40}$Ca, $^{112}$Sn, $^{181}$Ta, $^{197}$Au and $^{238}$U from a low to high incident momentum. The rapidity and momentum distributions of $\\pi^{+}$ and protons from the LEAR measurements can be well reproduced. The impacts of system size and incident momentum on particle emissions are investigated from the inclusive spectra, transverse momentum and rapidity distributions. It is found that the annihilations of $\\overline{p}$ on nucleons are of importance on the particle production. Hyperons are mainly produced via meson induced reactions on nucleons and strangeness exchange collisions when the incident momentum is below the threshold value of annihilation reaction. A higher nuclear temperature is obtained from the kaon emission, but it has a lower value for hyperon production.

Zhao-Qing Feng; Horst Lenske

2014-05-07

13

Force variations on particle induced by bubble-particle collision  

Microsoft Academic Search

The force variation on a particle during a bubble-particle collision is investigated in two different liquid phases: (1) distilled water and (2) 80 wt% glycerin in water solution. The force variations on a stationary particle due to the collision are experimentally measured and the collision processes are visualized. A simple analytical model of the collision process is developed to account

T. Hong; L.-S. Fan; D. J. Lee

1999-01-01

14

Calcium oxalate nephrolithiasis, a free or fixed particle disease  

Microsoft Academic Search

Calcium oxalate nephrolithiasis, a free or fixed particle disease. The chances of stone formation occurring through a free particle mechanism were calculated using the approach of Finlayson and Reid [1]. For these calculations we used new data on nephron dimensions, supersaturation and crystal growth rates in urine, and also incorporated the size increasing effect of crystal agglomeration. The calculations were

Dirk J Kok; Saeed R Khan

1994-01-01

15

Drug-induced hyperthermia in Huntington's disease.  

PubMed

Until now, only three patients with Huntington's disease (HD) and a neuroleptic malignant syndrome (NMS) have been reported in the literature. We describe four cases with advanced stage Huntington's disease who within a period of one year developed drug-induced hyperthermia, either the neuroleptic malignant syndrome, or the serotonin syndrome. Possible contributing factors that may have been specific for HD patients could be identified and included advanced neurological disease with severe illness, occurrence in summer, with possible infectious disease, dehydration, and pre-existing extra-pyramidal signs that may mask incipient NMS/serotonin syndrome. Measures to avoid these potentially lifethreatening conditions are discussed. PMID:15083292

Gaasbeek, D; Naarding, P; Stor, T; Kremer, H P H

2004-04-01

16

A human norovirus-like particle vaccine adjuvanted with ISCOM or mLT induces cytokine and antibody responses and protection to the homologous GII.4 human norovirus in a gnotobiotic pig disease model  

PubMed Central

We inoculated gnotobiotic pigs oraly/intranasally with human norovirus GII.4 HS66 strain virus-like particles (VLP) and immunostimulating complexes (ISCOM) or mutant E. coli LT toxin (mLT, R192G) as mucosal adjuvants, then assessed intestinal and systemic antibody and cytokine responses and homologous protection. Both vaccines induced high rates of seroconversion (100%) and coproconversion (75–100%). The VLP+mLT vaccine induced Th1/Th2 serum cytokines and cytokine secreting cells, whereas the VLP+ISCOM vaccine induced Th2 biased responses with significantly elevated IgM, IgA and IgG antibody-secreting cells in intestine. Nevertheless, both vaccines induced increased protection rates against viral shedding and diarrhea (75–100%) compared to controls; however, only 57% of controls shed virus. PMID:18022293

Souza, Menira; Costantini, Veronica; Azevedo, Marli S. P; Saif, Linda J.

2014-01-01

17

Pulmonary Effects Induced by Ultrafine PTFE Particles  

Microsoft Academic Search

PTFE (polytetrafluoroethylene) fumes consisting of large numbers of ultrafine (uf) particles and low concentrations of gas-phase compounds can cause severe acute lung injury. Our studies were designed to test three hypotheses: (i) uf PTFE fume particles are causally involved in the induction of acute lung injury, (ii) uf PTFE elicit greater pulmonary effects than larger sized PTFE accumulation mode particles,

Carl J. Johnston; Jacob N. Finkelstein; Pamela Mercer; Nancy Corson; Robert Gelein; Günter Oberdörster

2000-01-01

18

Particle-induced cytokine responses in cardiac cell cultures--the effect of particles versus soluble mediators released by particle-exposed lung cells.  

PubMed

Increased levels of particulate matter have been associated with adverse effects in the respiratory as well as the cardiovascular system. The biological mechanisms behind these associations are still unresolved. Among potential mechanisms, particulate matter-associated cardiac effects may be initiated by inhaled small-sized particles, particle components and/or mediators related to inflammation that translocate into the pulmonary circulation. In the present study cytokine responses (interleukin [IL]-6, IL-1beta, and tumor necrosis factor [TNF]-alpha) of primary rat cardiomyocytes and cardiofibroblasts in mono- and cocultures induced by direct exposure to particles, were compared with cytokine responses induced by mediators released by particle-exposed primary rat epithelial lung cells (conditioned media). Cells were exposed to a model ultrafine particle (ultrafine carbon black, Printex 90) and in selected experiments to an urban air particle sample (SRM 1648, St Louis, MO). In lung cell cultures both particle types induced release of IL-6 and IL-1beta, whereas TNF-alpha was only detected upon exposure to St Louis particles. The release of IL-6 by cardiac cells was strongly enhanced upon exposure to conditioned media, and markedly exceeded the response to direct particle exposure. IL-1, but not TNF-alpha, seemed necessary, but not sufficient, for this enhanced IL-6 release. The role of IL-1 was demonstrated by use of an IL-1 receptor antagonist that partially reduced the effect of the conditioned media, and by a stimulating effect on the cardiac cell release of IL-6 by exogenous addition of IL-1alpha and IL-1beta. These in vitro findings lend support to the hypothesis that particle-induced cardiac inflammation and disease may involve lung-derived mediators. PMID:18700232

Totlandsdal, Annike I; Refsnes, Magne; Skomedal, Tor; Osnes, Jan-Bjørn; Schwarze, Per E; Låg, Marit

2008-11-01

19

Suppression of nanosilica particle-induced inflammation by surface modification of the particles.  

PubMed

It has gradually become evident that nanomaterials, which are widely used in cosmetics, foods, and medicinal products, could induce substantial inflammation. However, the roles played by the physical characteristics of nanomaterials in inflammatory responses have not been elucidated. Here, we examined how particle size and surface modification influenced the inflammatory effects of nanosilica particles, and we investigated the mechanisms by which the particles induced inflammation. We compared the inflammatory effects of silica particles with diameters of 30-1,000 nm in vitro and in vivo. In macrophages in vitro, 30- and 70-nm nanosilica particles (nSP30 and nSP70) induced higher production of tumor necrosis factor-? (TNF?) than did larger particles. In addition, intraperitoneal injection of nSP30 and nSP70 induced stronger inflammatory responses involving cytokine production than did larger particles in mice. nSP70-induced TNF? production in macrophage depended on the production of reactive oxygen species and the activation of mitogen-activated protein kinases (MAPKs). Furthermore, nSP70-induced inflammatory responses were dramatically suppressed by surface modification of the particles with carboxyl groups in vitro and in vivo; the mechanism of the suppression involved reduction in MAPK activation. These results provide basic information that will be useful for the development of safe nanomaterials. PMID:22418595

Morishige, Tomohiro; Yoshioka, Yasuo; Inakura, Hiroshi; Tanabe, Aya; Narimatsu, Shogo; Yao, Xinglei; Monobe, Youko; Imazawa, Takayoshi; Tsunoda, Shin-ichi; Tsutsumi, Yasuo; Mukai, Yohei; Okada, Naoki; Nakagawa, Shinsaku

2012-08-01

20

Role of Reactive Oxygen Species on Diesel Exhaust Particle-Induced Cytotoxicity in Rat Cardiac Myocytes  

Microsoft Academic Search

Exposure to air pollution containing diesel exhaust particles (DEP) is associated with an increase in mortality rate attributed to cardiovascular diseases, but the mechanisms by which DEP produces adverse cardiovascular effects at the cellular level are not elucidated. This study investigated the cytotoxic mechanisms underlying DEP-induced neonatal rat cardiac myocytes effects in vitro, focusing on the role of reactive oxygen

Yuta Okayama; Masayoshi Kuwahara; Akira K. Suzuki; Hirokazu Tsubone

2006-01-01

21

Dielectric response of particles in flowing media: The effect of shear-induced rotation on the variation in particle polarizability  

Microsoft Academic Search

When particles in liquid suspensions flow through channels and pipes in a laminar fashion, the resulting parabolic velocity profile gives rise to shear, which induces the particles to rotate. If flowing suspensions containing dielectric particles are immersed in an external electric field, the anisotropic polarization induced in rotating nonspherical particles will vary with the orientation of the particle with respect

Marija Nikolic-Jaric; Graham A. Ferrier; Douglas J. Thomson; Greg E. Bridges; Mark R. Freeman

2011-01-01

22

RESEARCH ARTICLE Open Access Oestrogen deficiency modulates particle-induced  

E-print Network

1 and Moussa Hamadouche1 Abstract Introduction: Postmenopausal osteoporosis may modulate bone and by histomorphometry, PE particles induced extensive bone resorption and an intense inflammatory reaction in normal mice after PE implantation. Introduction Aseptic loosening of total joint replacements develops

Boyer, Edmond

23

Virus-Like Particle Vaccine Induces Protective Immunity against Homologous and Heterologous Strains of Influenza Virus  

Microsoft Academic Search

Recurrent outbreaks of highly pathogenic avian influenza virus pose the threat of pandemic spread of lethal disease and make it a priority to develop safe and effective vaccines. Influenza virus-like particles (VLPs) have been suggested to be a promising vaccine approach. However, VLP-induced immune responses, and their roles in inducing memory immune responses and cross-protective immunity have not been investigated.

Fu-Shi Quan; Chunzi Huang; Richard W. Compans; Sang-Moo Kang

2007-01-01

24

[Drug-induced interstitial lung diseases].  

PubMed

Drug-induced infiltrative lung disease may manifest as variable clinical radiological patterns, including subacute or chronic interstitial pneumonia, pulmonary fibrosis, eosinophilic pneumonia, organising pneumonia, pulmonary edema, or sarcoidosis. A large amount of drugs have been incriminated, including those used in cardiovascular diseases (amiodarone, statins and angiotensin converting enzyme inhibitors), antibiotics (minocycline, nitrofurantoin), most of anticancer drugs (and especially chemotherapy and chest radiation), treatment of rheumatoid arthritis, as well as more recent drugs. A high index of suspicion is therefore required in any patient with infiltrative lung disease and the web-based tool www.pneumotox.com will help to list possible causative drugs. The following steps are necessary: history and timing of drug exposure, clinical and imaging pattern, exclusion of other causes of infiltrative lung disease, improvement following drug discontinuation. Rechallenge, dangerous, is not recommended. PMID:25362778

Bonniaud, Philippe; Georges, Marjolaine; Favrolt, Nicolas; Camus, Philippe

2014-09-01

25

Optics of spin-1 particles from gravity-induced phases  

E-print Network

The Maxwell and Maxwell-de Rham equations can be solved exactly to first order in an external gravitational field. The gravitational background induces phases in the wave functions of spin-1 particles. These phases yield the optics of the particles without requiring any thin lens approximation.

G. Papini; G. Scarpetta; A. Feoli; G. Lambiase

2007-11-19

26

Particle climbing induced by reciprocating air flow  

NASA Astrophysics Data System (ADS)

We present in this letter a phenomenon of "particle climbing against gravity," in which granular materials rise against gravity and fill a container placed upside down on the surface of the vibrating granular layer. While the granular layer vibrates, the pressure at the top of the container fluctuates above and below the atmospheric pressure, and a reciprocating air flow existing between the tube and the bed brings the particles' directional upwards movements, which can be used to develop the methods of granular material hoisting and transporting.

Liu, Chuanping; Wu, Ping; Zhang, Fuweng; Wang, Li

2013-05-01

27

Intrinsic particle-induced lateral transport in microchannels  

PubMed Central

In microfluidic systems at low Reynolds number, the flow field around a particle is assumed to maintain fore-aft symmetry, with fluid diverted by the presence of a particle, returning to its original streamline downstream. This current model considers particles as passive components of the system. However, we demonstrate that at finite Reynolds number, when inertia is taken into consideration, particles are not passive elements in the flow but significantly disturb and modify it. In response to the flow field, particles translate downstream while rotating. The combined effect of the flow of fluid around particles, particle rotation, channel confinement (i.e., particle dimensions approaching those of the channel), and finite fluid inertia creates a net recirculating flow perpendicular to the primary flow direction within straight channels that resembles the well-known Dean flow in curved channels. Significantly, the particle generating this flow remains laterally fixed as it translates downstream and only the fluid is laterally transferred. Therefore, as the particles remain inertially focused, operations can be performed around the particles in a way that is compatible with downstream assays such as flow cytometry. We apply this particle-induced transfer to perform fluid switching and mixing around rigid microparticles as well as deformable cells. This transport phenomenon, requiring only a simple channel geometry with no external forces to operate, offers a practical approach for fluid transfer at high flow rates with a wide range of applications, including sample preparation, flow reaction, and heat transfer. PMID:22761309

Amini, Hamed; Sollier, Elodie; Weaver, Westbrook M.; Di Carlo, Dino

2012-01-01

28

Amorphous nanosilica particles induce ROS generation in Langerhans cells.  

PubMed

Generation of total intracellular reactive oxygen species (ROS) was measured in XS52 cells, a Langerhans cell-like line, treated with different sized amorphous silica particles. The results suggested that exposure to amorphous nanosilica particles (nSPs) with a particle size of 70 nm induced a higher level of ROS generation than did exposure to micron-sized amorphous silica particles. This finding means that it is essential to examine the biological effects of ROS generated after exposure to nSPs, which will provide useful information for hazard identification as well as the design of safer nanomaterials. PMID:22957442

Yoshida, T; Yoshikawa, T; Nabeshi, H; Matsuyama, K; Hirai, T; Akase, T; Yoshioka, Y; Itoh, N; Tsutsumi, Y

2012-08-01

29

Ripple induced trapped particle loss in tokamaks  

SciTech Connect

The threshold for stochastic transport of high energy trapped particles in a tokamak due to toroidal field ripple is calculated by explicit construction of primary resonances, and a numerical examination of the route to chaos. Critical field ripple amplitude is determined for loss. The expression is given in magnetic coordinates and makes no assumptions regarding shape or up-down symmetry. An algorithm is developed including the effects of prompt axisymmetric orbit loss, ripple trapping, convective banana flow, and stochastic ripple loss, which gives accurate ripple loss predictions for representative Tokamak Fusion Test Reactor and International Thermonuclear Experimental Reactor equilibria. The algorithm is extended to include the effects of collisions and drag, allowing rapid estimation of alpha particle loss in tokamaks.

White, R.B.

1996-05-01

30

Aeolian Induced Erosion and Particle Entrainment  

NASA Technical Reports Server (NTRS)

The Granular Physics Department at The Kennedy Space Center is addressing the problem of erosion on the lunar surface. The early stages of research required an instrument that would produce erosion at a specific rate with a specific sample variation. This paper focuses on the development and experimental procedures to measure and record erosion rates. This was done with the construction of an open air wind tunnel, and examining the relationship between airflow and particle motion.

Saint, Brandon

2007-01-01

31

Transient Flow Induced by the Adsorption of Particles  

NASA Astrophysics Data System (ADS)

When small particles, e.g., glass, flour, pollen, etc., come in contact with a fluid-liquid interface they disperse so quickly to form a monolayer on the interface that it appears explosive, especially on the surface of mobile liquids like water. This is a consequence of the fact that the adsorption of a particle in an interface causes a lateral flow which on the interface away from the particle. In this study we use the particle image velocimetry (PIV) technique to measure the transient three-dimensional flow that arises due to the adsorption of spherical particles. The PIV measurements show that the flow develops a fraction of a second after the adsorption of the particle and persists for several seconds. The fluid below the particle rises upwards and on the surface moves away from the particle. These latter PIV results are consistent with the surface velocity measurements performed in earlier studies. The strength of the induced flow, and the time duration for which the flow persists, both decrease with decreasing particle size. For a spherical particle the flow is axisymmetric about the vertical line passing through the center of the particle.

Musunuri, Naga; Codjoe, Daniel; Dalal, Bhavin; Fischer, Ian; Singh, Pushpendra

2013-03-01

32

Apoptosis in animal models of virus-induced disease  

Microsoft Academic Search

Apoptosis is associated with virus-induced human diseases of the central nervous system, heart and liver, and causes substantial morbidity and mortality. Although virus-induced apoptosis is well characterized in individual cells in cell culture, virus-induced apoptosis in vivo and the role of apoptosis in virus-induced disease is not well established. This Review focuses on animal models of virus-induced diseases of the

Kenneth L. Tyler; Penny Clarke

2009-01-01

33

Plasma-Particle Interactions in a Laser-Induced Plasma: Implications for Laser-Induced  

E-print Network

Plasma-Particle Interactions in a Laser-Induced Plasma: Implications for Laser-Induced Breakdown of Florida, Gainesville, Florida 32611-6300 The interaction between laser-induced plasmas and indi- vidual of tens of microseconds within plasmas formed by 300-mJ Nd: YAG laser pulses. Significant spatial

Hahn, David W.

34

Infectious particles, stress, and induced prion amyloids  

PubMed Central

Transmissible encephalopathies (TSEs) are believed by many to arise by spontaneous conversion of host prion protein (PrP) into an infectious amyloid (PrP-res, PrPSc) without nucleic acid. Many TSE agents reside in the environment, with infection controlled by public health measures. These include the disappearance of kuru with the cessation of ritual cannibalism, the dramatic reduction of epidemic bovine encephalopathy (BSE) by removal of contaminated feed, and the lack of endemic scrapie in geographically isolated Australian sheep with susceptible PrP genotypes. While prion protein modeling has engendered an intense focus on common types of protein misfolding and amyloid formation in diverse organisms and diseases, the biological characteristics of infectious TSE agents, and their recognition by the host as foreign entities, raises several fundamental new directions for fruitful investigation such as: (1) unrecognized microbial agents in the environmental metagenome that may cause latent neurodegenerative disease, (2) the evolutionary social and protective functions of different amyloid proteins in diverse organisms from bacteria to mammals, and (3) amyloid formation as a beneficial innate immune response to stress (infectious and non-infectious). This innate process however, once initiated, can become unstoppable in accelerated neuronal aging. PMID:23633671

2013-01-01

35

External front instabilities induced by a shocked particle ring  

NASA Astrophysics Data System (ADS)

The dispersion of a cylindrical particle ring by a blast or shock wave induces the formation of coherent structures which take the form of particle jets. A blast wave, issuing from the discharge of a planar shock wave at the exit of a conventional shock tube, is generated in the center of a granular medium ring initially confined inside a Hele-Shaw cell. With the present experimental setup, under impulsive acceleration, a solid particle-jet formation is observed in a quasi-two-dimensional configuration. The aim of the present investigation is to observe in detail the formation of very thin perturbations created around the external surface of the dispersed particle layer. By means of fast flow visualization with an appropriate recording window, we focus solely on the first instants during which the external particle ring becomes unstable. We find that the critical area of the destabilization of the external ring surface is constant regardless of the acceleration of the initial layer. Moreover, we observe in detail the external front perturbation wavelength, rendered dimensionless by the initial ring perimeter, and follow its evolution with the initial particle layer acceleration. We report this quantity to be constant regardless of the evolution of the initial particle layer acceleration. Finally, we can reasonably assert that external front perturbations depend solely on the material of the particles.

Rodriguez, V.; Saurel, R.; Jourdan, G.; Houas, L.

2014-10-01

36

CARDIAC MOLECULAR EFFECTS INDUCED BY AIR POLLUTION PARTICLES  

EPA Science Inventory

Abstract Submitted to the American Thoracic Society 98th International Conference, May 17 - 22, 2002, Atlanta, GA CARDIAC MOLECULAR EFFECTS INDUCED BY AIR POLLUTION PARTICLES K. Dreher1, R. Jaskot1, J. Richards1, and T. Knuckles2. 1U. S. Environmental Protection Agency,...

37

A compilation of charged-particle induced thermonuclear reaction rates  

Microsoft Academic Search

Low-energy cross section data for 86 charged-particle induced reactions involving light (1 ? Z ? 14), mostly stable, nuclei are compiled. The corresponding Maxwellian-averaged thermonuclear reaction rates of relevance in astrophysical plasmas at temperatures in the range from 106 K to 1010 K are calculated. These evaluations assume either that the target nuclei are in their ground state, or that

C. Angulo; M. Arnould; M. Rayet; P. Descouvemont; D. Baye; C. Leclercq-Willain; A. Coc; S. Barhoumi; P. Aguer; C. Rolfs; R. Kunz; J. W. Hammer; A. Mayer; T. Paradellis; S. Kossionides; C. Chronidou; K. Spyrou; S. Degl'Innocenti; G. Fiorentini; B. Ricci; S. Zavatarelli; C. Providencia; H. Wolters; J. Soares; C. Grama; J. Rahighi; A. Shotter; M. Lamehi Rachti

1999-01-01

38

Jet and inclusive particle production in photon induced collisions  

E-print Network

Recent progress in application of higher order QCD calculations to jet and inclusive particle production in photon induced collisions is reviewed. Attention is paid to theoretical uncertainties of such calculations, particularly those coming from the choice of renormalization and factorization scales.

Jiri Chyla

2005-11-10

39

Nilotinib-induced interstitial lung disease.  

PubMed

Nilotinib is a second-generation tyrosine kinase inhibitor active in patients with chronic myeloid leukemia (CML) resistant to imatinib, and has been recently approved for newly diagnosed patients. We present a case of nilotinib-induced interstitial lung disease (ILD). A 67-year-old female patient was initially treated with imatinib for chronic-phase Philadelphia chromosome-positive (Ph(+)) CML. Imatinib was replaced by nilotinib because of hematological toxicity. The patient had received nilotinib for about 3 years without significant adverse effects. She visited the clinic due to chronic cough; chest X-ray revealed consolidations in both lung fields. Nilotinib-induced ILD was diagnosed based on intensive workup, including lung biopsy. She responded dramatically to corticosteroid therapy. To our knowledge, this is the first reported case of nilotinib-induced ILD in a patient with Ph(+) CML. We emphasize that if unexplained lung abnormalities progress in patients receiving nilotinib, physicians should consider this potentially fatal complication in their differential diagnoses. PMID:23877149

Go, Se-Il; Lee, Won Sup; Lee, Gyeong-Won; Kang, Jung Hun; Kang, Myung Hee; Lee, Jeong-Hee; Kim, Hoon-Gu

2013-09-01

40

Foot-and-mouth disease virus-like particles produced by a SUMO fusion protein system in Escherichia coli induce potent protective immune responses in guinea pigs, swine and cattle  

PubMed Central

Foot-and-mouth disease virus (FMDV) causes a highly contagious infection in cloven-hoofed animals. The format of FMD virus-like particles (VLP) as a non-replicating particulate vaccine candidate is a promising alternative to conventional inactivated FMDV vaccines. In this study, we explored a prokaryotic system to express and assemble the FMD VLP and validated the potential of VLP as an FMDV vaccine candidate. VLP composed entirely of FMDV (Asia1/Jiangsu/China/2005) capsid proteins (VP0, VP1 and VP3) were simultaneously produced as SUMO fusion proteins by an improved SUMO fusion protein system in E. coli. Proteolytic removal of the SUMO moiety from the fusion proteins resulted in the assembly of VLP with size and shape resembling the authentic FMDV. Immunization of guinea pigs, swine and cattle with FMD VLP by intramuscular inoculation stimulated the FMDV-specific antibody response, neutralizing antibody response, T-cell proliferation response and secretion of cytokine IFN-?. In addition, immunization with one dose of the VLP resulted in complete protection of these animals from homologous FMDV challenge. The 50% protection dose (PD50) of FMD VLP in cattle is up to 6.34. These results suggest that FMD VLP expressed in E. coli are an effective vaccine in guinea pigs, swine and cattle and support further development of these VLP as a vaccine candidate for protection against FMDV. PMID:23826638

2013-01-01

41

Phason-induced dynamics of colloidal particles on quasicrystalline substrates.  

PubMed

Phasons are special hydrodynamic modes that occur in quasicrystals. The trajectories of particles due to a phasonic drift were recently studied by Kromer et al. (Phys. Rev. Lett. 108, 218301 (2012)) for the case where the particles stay in the minima of a quasicrystalline potential. Here, we study the mean motion of colloidal particles in quasicrystalline laser fields when a phasonic drift or displacement is applied and also consider the cases where the colloids cannot follow the potential minima. While the mean square displacement is similar to the one of particles in a random potential with randomly changing potential wells, there also is a net drift of the colloids that reverses its direction when the phasonic drift velocity is increased. Furthermore, we explore the dynamics of the structural changes in a laser-induced quasicrystal during the rearrangement process that is caused by a steady phasonic drift or an instantaneous phasonic displacement. PMID:23512714

A Kromer, Justus; Schmiedeberg, Michael; Roth, Johannes; Stark, Holger

2013-03-01

42

Iron-Induced Fibrin in Cardiovascular Disease  

PubMed Central

Accumulating evidence within the last two decades indicates the association between cardiovascular disease (CVD) and chronic inflammatory state. Under normal conditions fibrin clots are gradually degraded by the fibrinolytic enzyme system, so no permanent insoluble deposits remain in the circulation. However, fibrinolytic therapy in coronary and cerebral thrombosis is ineffective unless it is installed within 3-5 hours of the onset. We have shown that trivalent iron (FeIII) initiates a hydroxyl radical-catalyzed conversion of fibrinogen into a fibrin-like polymer (parafibrin) that is remarkably resistant to the proteolytic dissolution and thus promotes its intravascular deposition. Here we suggest that the persistent presence of proteolysis-resistant fibrin clots causes chronic inflammation. We study the effects of certain amphiphilic substances on the iron- and thrombin-induced fibrinogen polymerization visualized using scanning electron microscopy. We argue that the culprit is an excessive accumulation of free iron in blood, known to be associated with CVD. The only way to prevent iron overload is by supplementation with iron chelating agents. However, administration of free radical scavengers as effective protection against persistent presence of fibrin-like deposits should also be investigated to contribute to the prevention of cardiovascular and other degenerative diseases. PMID:23721262

Lipinski, Boguslaw; Pretorius, Etheresia

2013-01-01

43

Predicted cross-sections for photon-induced particle emission  

Microsoft Academic Search

Cross-sections for the photon-induced particle-emission reactions (?,n), (?,p), and (?,?) are given for all natural isotopes from Ti to Bi. The target nuclei are assumed to be in their ground states, except for 180Ta which is naturally occurring as the isomer 180mTa. The cross-sections are calculated in a statistical model (Hauser–Feshbach) approach and covering an energy range from threshold up

T. Rauscher; F.-K. Thielemann

2004-01-01

44

Gravitationally induced particle production: Thermodynamics and kinetic theory  

NASA Astrophysics Data System (ADS)

A relativistic kinetic description for the irreversible thermodynamic process of gravitationally induced particle production is proposed in the context of an expanding Friedmann-Robertson-Walker geometry. We show that the covariant thermodynamic treatment referred to as "adiabatic" particle production provoked by the cosmic time-varying gravitational field has a consistent kinetic counterpart. The variation of the distribution function is associated to a noncollisional kinetic term of quantum-gravitational origin which is proportional to the ratio ?/H, where ? is the gravitational particle production rate and H is the Hubble parameter. For ? ?H the process is negligible and as should be expected it also vanishes (regardless of the value of ?) in the absence of gravitation. The resulting nonequilibrium distribution function has the same functional form of equilibrium with the evolution laws corrected by the particle production process. The macroscopic temperature evolution law is also kinetically derived for massive and massless particles. The present approach points to the possibility of an exact (semiclassical) quantum-gravitational kinetic treatment by incorporating backreaction effects in the cosmic background.

Lima, J. A. S.; Baranov, I.

2014-08-01

45

Mycoplasma arthritidis-induced ocular inflammatory disease.  

PubMed Central

Mycoplasma arthritidis was demonstrated to incite experimental conjunctivitis and uveitis in Swiss Webster mice which have a known susceptibility to the arthritis customarily associated with infection by this mycoplasma. The initial symptom of ocular involvement was conjunctivitis, which appeared as early as 1 day after intravenous injection with viable culture concentrates of M. arthritidis. By day 2, histological analysis showed intraocular localized inflammatory reactions that were confined primarily to the anterior portion of the uvea and produced results which were compatible with those seen in iridocyclitis. Serological assays of the titer and the class of antibodies involved in the early humoral immune response to infection confirmed the predominance of immunoglobulin G (IgG) concentrations over IgM concentrations that was described by others (Cole et al., Infect. Immun. 4:431-440, 1971) and revealed significant titers of the IgG2a and IgG2b subclasses of complement-fixing antibodies. The rapid onset of acute conjunctivitis, together with the early appearance of immunoglobulins of the IgG class, suggests that the M. arthritidis-infected Swiss Webster mice may have experienced an anamnestic response to the mycoplasma antigens. These observations introduce a new animal model for the study of mycoplasma-induced experimental uveitis and conjunctivitis, which are demonstrated here to accompany a disseminated systemic disease process. Images PMID:7200961

Thirkill, C E; Gregerson, D S

1982-01-01

46

SENSITIZATION AND EXACERBATION OF ALLERGIC DISEASES BY DIESEL ENGINE PARTICLES  

SciTech Connect

Most studies of the health effects of diesel exhaust have focused on the controversial issue of its role in cancer. However, recently the role of combustion products such as diesel exhaust particles (DEP) in modulating the immune response has garnered much attention. In particular the effect of DEP on allergic and asthmatic diseases has been the focus of many studies. A link between industrialization and allergic disease has long been presumed. Indeed, only 50 years after the first recorded reported case of allergy in 1819, Charles Blackely wrote that the ''hay-fever epidemic'' was associated with the movement of people from the country into the cities. Ishizaki et al. (1987) found that people in Japan living on busy roads lined with cedar trees have more allergies to cedar than residents living on similar streets with much less traffic. Since that time other epidemiological studies have reported similar findings. Kramer, et al., showed that hay fever is greater in residential areas with heavy truck traffic, while Weiland, et al., reported that allergic symptoms correlate with the distance of residences to roads with heavy traffic.

Diaz-Sanchez, David

2000-08-20

47

Metal-Induced Lung Disease. Lessons from Japan's Experience  

Microsoft Academic Search

Abstract: Metal-Induced Lung Disease: Lessons from Japan’s Experience: Yukinori K USAKA, et al. Department of Environmental Health, School of Medicine, Fukui Medical University— Metals inducing occupational respiratory diseases, e.g. metal fever, acute and chronic pneumonia, asthma, bronchitis, chronic obstructive lung disease, pulmonary fibrosis and lung cancer are described. The metals mentioned are the following: aluminum, antimony, arsenic, barium, beryllium, cadmium,

Yukinori KUSAKA; Kazuhiro SATO; Narufumi SUGANUMA; Yutaka HOSODA

2001-01-01

48

Diabetes mellitus may induce cardiovascular disease by decreasing neuroplasticity  

PubMed Central

Summary Neuroplasticity has been defined “the ability of the nervous system to respond to intrinsic or extrinsic stimuli by reorganizing its structure, function and connections”. The nervous system monitors and coordinates internal organ function. Thus neuroplasticity may be associated with the pathogenesis of other diseases besides neuropsychiatric diseases. Decreased neuroplasticity is associated with cardiovascular disease (CVD) and a disease related to decreased neuroplasticity may confer a greater CVD risk. Diabetes mellitus (DM) is related to CVD and DM induces decreased neuroplasticity, which is manifested as depression, Alzheimer’s disease and diabetic neuropathy. Therefore we conclude that DM may induce CVD by decreasing neuroplasticity. PMID:25014044

Zheng, Zhihua; Wu, Junyan; Wang, Ruolun; Zeng, Yingtong

2014-01-01

49

The EPIC-MOS Particle-Induced Background Spectrum  

NASA Technical Reports Server (NTRS)

We have developed a method for constructing a spectrum of the particle-induced instrumental background of the XMM-Newton EPIC MOS detectors that can be used for observations of the diffuse background and extended sources that fill a significant fraction of the instrument field of view. The strength and spectrum of the particle-induced background, that is, the background due to the interaction of particles with the detector and the detector surroundings, is temporally variable as well as spatially variable over individual chips. Our method uses a combination of the filter-wheel-closed data and a database of unexposed-region data to construct a spectrum of the "quiescent" background. We show that, using this method of background subtraction, the differences between independent observations of the same region of "blank sky" are consistent with the statistical uncertainties except when there is clear evidence of solar wind charge exchange emission. We use the blank sky observations to show that contamination by SWCX emission is a strong function of the solar wind proton flux, and that observations through the flanks of the magnetosheath appear to be contaminated only at much higher solar wind fluxes. We have also developed a spectral model of the residual soft proton flares, which allows their effects to be removed to a substantial degree during spectral fitting.

Kuntz, K. D.; Snowden, S. L.

2006-01-01

50

Radiation-induced coronary artery disease  

SciTech Connect

This report describes three patients who developed myocardial infarction at an untimely age, 4 to 12 years after radiation therapy for Hodgkin's disease. These cases lend credence to the cause and effect relation of such therapy to coronary artery disease.

Dunsmore, L.D.; LoPonte, M.A.; Dunsmore, R.A.

1986-07-01

51

Cellular Chemotaxis Induced by Wear Particles from Joint Replacements  

PubMed Central

The destruction of bone around joint replacements (periprosthetic osteolysis) is an adverse biological response associated with the generation of excessive wear particles. Wear debris from the materials used for joint replacements stimulate a chronic inflammatory and foreign body reaction that leads to increased osteoclast differentiation and maturation, and decreased bone formation. Wear debris induces both local and systemic trafficking of inflammatory cells to the site of particle generation. Recent studies have shown that this effect is mediated primarily by chemotactic cytokines (chemokines) including macrophage chemotactic protein-1 (MCP-1, also known as CCL2), macrophage inhibitory protein-1 (MIP-1), Interleukin-8 (IL-8 or CXCL8) and others. These ligands migrate along a concentration gradient to interact with G-protein-linked transmembrane receptors on the cell surface. Chemokines are involved in the innate and adaptive immune responses, angiogenesis, wound healing and tissue repair. In vitro, in vivo and tissue retrieval studies have shown that chemokine-directed systemic trafficking of polymorphonuclear leukocytes and cells of the monocyte/macrophage lineage to wear particles results in the release of pro-inflammatory factors and subsequent bone loss. Modulation of the chemokine ligand-receptor axis is a potential strategy to mitigate the adverse effects of wear particles from joint replacements. PMID:20398931

Goodman, Stuart B.; Ma, Ting

2010-01-01

52

Solar radiation induced rotational bursting of interplanetary particles  

NASA Technical Reports Server (NTRS)

It is suggested that the magnitudes of the two radiation-induced rotational bursting mechanisms (Radzieskii effect and windmill effect) have been overestimated and that they do not work significantly faster than the Poynting-Robertson effect in removing interplanetary particles. These two mechanisms are described, and serious doubts are raised regarding the derivation of their radiation pressure-torque proportionality constants, which are required for calculating their magnitudes. It is shown that both mechanisms will cause the alignment of elongated particles and, consequently, the polarization of zodiacal light. Since no positive polarization has been measured at the antisolar point, it is concluded that the magnitudes of the rotational bursting mechanisms are smaller than that of the Poynting-Robertson effect.

Sparrow, J. G.

1975-01-01

53

DNA damage response induced by HZE particles in human cells  

NASA Astrophysics Data System (ADS)

Convincing evidences indicate that high-linear energy transfer (LET) ionizing radiation (IR) induced complex DNA lesions are more difficult to repair than isolated DNA lesions induced by low-LET IR; this has been associated with the increased RBE for cell killing, chromosomal aberrations, mutagenesis, and carcinogenesis in high energy charged-particle irradiated human cells. We have employed an in situ method to directly monitor induction and repair of clustered DNA lesions at the single-cell level. We showed, consistent with biophysical modeling, that the kinetics of loss of clustered DNA lesions was substantially compromised in human fibroblasts. The unique spatial distribution of different types of DNA lesions within the clustered damages determined the cellular ability to repair these damages. Importantly, examination of metaphase cells derived from HZE particle irradiated cells revealed that the extent of chromosome aberrations directly correlated with the levels of unrepaired clustered DNA lesions. In addition, we used a novel organotypic human lung three-dimensional (3D) model to investigate the biological significance of unrepaired DNA lesions in differentiated lung epithelial cells. We found that complex DNA lesions induced by HZE particles were even more difficult to be repaired in organotypic 3D culture, resulting enhanced cell killing and chromosome aberrations. Our data suggest that DNA repair capability in differentiated cells renders them vulnerable to DSBs, promoting genome instability that may lead to carcinogenesis. As the organotypic 3D model mimics human lung, it opens up new experimental approaches to explore the effect of radiation in vivo and will have important implications for evaluating radiation risk in human tissues.

Chen, David; Aroumougame, Asaithamby

54

Electron and photon-induced complex particle emission  

Microsoft Academic Search

Electron- and photon-induced emission of d, t, 3He and alpha-particles from 12C, 27Al, 56Fe, 58Ni, 60Ni, 92Mo, 94Mo, natSn, 181Ta and 197Au has been studied with electrons of energies 30-140 MeV. The data are presented as energy spectra, angular distributions and excitation functions. It is shown that a model which includes pre-equilibrium emission following high-energy photon absorption on a quasideuteron

A. G. Flowers; P. J. Thorley; I. Anthony; D. Branford; J. C. McGeorge; M. R. Sene; A. C. Shotter; C. H. Zimmerman; R. O. Owens

1984-01-01

55

Induced radioactivity in and around high-energy particle accelerators.  

PubMed

Particle accelerators and their surroundings are locations of residual radioactivity production that is induced by the interaction of high-energy particles with matter. This paper gives an overview of the principles of activation caused at proton accelerators, which are the main machines operated at Conseil Européen pour la Recherche Nucléaire. It describes the parameters defining radio-nuclide production caused by beam losses. The second part of the paper concentrates on the analytic calculation of activation and the Monte Carlo approach as it is implemented in the FLUKA code. Techniques used to obtain, on the one hand, estimates of radioactivity in Becquerel and, on the other hand, residual dose rates caused by the activated material are discussed. The last part of the paper focuses on experiments that allow for benchmarking FLUKA activation calculations and on simulations used to predict activation in and around high-energy proton machines. In that respect, the paper addresses the residual dose rate that will be induced by proton-proton collisions at an energy of two times 7 TeV in and around the Compact Muon Solenoid (CMS) detector. Besides activation of solid materials, the air activation expected in the CMS cavern caused by this beam operation is also discussed. PMID:21697180

Vincke, Helmut; Theis, Chris; Roesler, Stefan

2011-07-01

56

Diesel exhaust particles induce the over expression of tumor necrosis factor-alpha (TNF-alpha) gene in alvelor machrophage and failed to induce apoptosis through activation of nuclear factor-kappaB (NF-kappaB)  

EPA Science Inventory

Exposure to particulate matter (PM2.5-10), including diesel exhaust particles (DEP) has been reported to induce lung injury and exacerbation of asthma and chronic obstructive pulmonary disease. Alveolar macrophages play a major role in the lung's response to inhaled particles and...

57

The effect of enoxacin on osteoclastogenesis and reduction of titanium particle-induced osteolysis via suppression of JNK signaling pathway.  

PubMed

The aim of this study was to assess the effect of enoxacin on osteoclastogenesis and titanium particle-induced osteolysis. Wear particles liberated from the surface of prostheses are associated with aseptic prosthetic loosening. It is well established that wear particles induce inflammation, and that extensive osteoclastogenesis plays a critical role in peri-implant osteolysis and subsequent prosthetic loosening. Therefore, inhibiting extensive osteoclast formation and bone resorption could be a potential therapeutic target to prevent prosthetic loosening. In this study, we demonstrated that enoxacin, a fluoroquinolone antibiotic, exerts potent inhibitory effects on titanium particle-induced osteolysis in a mouse calvarial model. Interestingly, the number of mature osteoclasts decreased after treatment with enoxacin in vivo, suggesting that osteoclast formation might be inhibited by enoxacin. We then performed in vitro studies to confirm our hypothesis and revealed the mechanism of action of enoxacin. Enoxacin inhibited osteoclast formation by specifically abrogating RANKL-induced JNK signaling. Collectively, these results suggest that enoxacin, an antibiotic with few side effects that is widely used in clinics, had significant potential for the treatment of particle-induced peri-implant osteolysis and other diseases caused by excessive osteoclast formation and function. PMID:24767789

Liu, Xuqiang; Qu, Xinhua; Wu, Chuanlong; Zhai, Zanjing; Tian, Bo; Li, Haowei; Ouyang, Zhengxiao; Xu, Xinchen; Wang, Wengang; Fan, Qiming; Tang, Tingting; Qin, An; Dai, Kerong

2014-07-01

58

A novel particle separation method based on induced-charge electro-osmotic flow and polarizability of dielectric particles.  

PubMed

A new microfluidic method of particle separation was proposed and studied theoretically in this paper. This method is based on the induced charge electro-osmotic flow (ICEOF) and polarizability of dielectric particles. In this method, a pair of metal plates is embedded on the side channel walls to create a region of circulating flows under applied electric field. When a dielectric particle enters this region, the vortices produced by ICEOF around the particle will interact with the circulating flows produced by the metal plates. Such hydrodynamic interaction influences the particle's trajectory, and may result in the particle being trapped in the flow circulating zone or passing through this flow circulating zone. Because the hydrodynamic interaction is sensitive to the applied electric field, and the polarizability and the size of the particles, separation of different particles can be realized by controlling these parameters. Comparing with electrophoresis and dielectrophoresis methods, this strategy presented in this paper is simple and sensitive. PMID:25043290

Zhang, Fang; Li, Dongqing

2014-10-01

59

Applying Particle Image Velocimetry to Map Fire Ant Alate Wing Beat Induced Flows Lichuan Gui1  

E-print Network

Applying Particle Image Velocimetry to Map Fire Ant Alate Wing Beat Induced Flows Lichuan Gui1, Mississippi A particle image velocimetry (PIV) system was built at the University of Mississippi's National

Gui, Lichuan

60

Diesel exhaust particles induce endothelial dysfunction in apoE{sup -/-} mice  

SciTech Connect

Background: Particulate air pollution can aggravate cardiovascular disease by mechanisms suggested to involve translocation of particles to the bloodstream and impairment of endothelial function, possibly dependent on present atherosclerosis. Aim: We investigated the effects of exposure to diesel exhaust particles (DEP) in vivo and ex vivo on vasomotor functions in aorta from apoE{sup -/-} mice with slight atherosclerosis and from normal apoE{sup +/+} mice. Methods: DEP 0, 0.5 or 5 mg/kg bodyweight in saline was administered i.p. The mice were sacrificed 1 h later and aorta ring segments were mounted on wire myographs. Segments from unexposed mice were also incubated ex vivo with 0, 10 and 100 {mu}g DEP/ml before measurement of vasomotor functions. Results: Exposure to 0.5 mg/kg DEP in vivo caused a decrease in the endothelium-dependent acetylcholine elicited vasorelaxation in apoE{sup -/-} mice, whereas the response was enhanced in apoE{sup +/+} mice. No significant change was observed after administration of 5 mg/kg DEP. In vivo DEP exposure did not affect constriction induced by K{sup +} or phenylephrine. In vitro exposure to 100 {mu}g DEP/ml enhanced acetylcholine-induced relaxation and attenuated phenylephrine-induced constriction. Vasodilation induced by sodium nitroprusside was not affected by any DEP exposure. Conclusion: Exposure to DEP has acute effect on vascular functions. Endothelial dysfunction possibly due to decreased NO production as suggested by decreased acetylcholine-induced vasorelaxation and unchanged sodium nitroprusside response can be induced by DEP in vivo only in vessels of mice with some atherosclerosis.

Hansen, Christian S. [Department of Environmental and Occupational Health, Institute of Public Health, University of Copenhagen, Oster Farimagsgade 5, Building 5B, 2nd Floor, 1014 Copenhagen K (Denmark); Sheykhzade, Majid [Department of Pharmacology and Pharmacotherapy, Danish University of Pharmaceutical Sciences (Denmark); Moller, Peter [Department of Environmental and Occupational Health, Institute of Public Health, University of Copenhagen, Oster Farimagsgade 5, Building 5B, 2nd Floor, 1014 Copenhagen K (Denmark); Folkmann, Janne Kjaergaard [Department of Environmental and Occupational Health, Institute of Public Health, University of Copenhagen, Oster Farimagsgade 5, Building 5B, 2nd Floor, 1014 Copenhagen K (Denmark); Amtorp, Ole [Department of Pharmacology, University of Copenhagen (Denmark); Jonassen, Thomas [Department of Pharmacology, University of Copenhagen (Denmark); Loft, Steffen [Department of Environmental and Occupational Health, Institute of Public Health, University of Copenhagen, Oster Farimagsgade 5, Building 5B, 2nd Floor, 1014 Copenhagen K (Denmark)]. E-mail: s.loft@pubhealth.ku.dk

2007-02-15

61

Schisantherin A suppresses osteoclast formation and wear particle-induced osteolysis via modulating RANKL signaling pathways.  

PubMed

Receptor activator of NF-?B ligand (RANKL) plays critical role in osteoclastogenesis. Targeting RANKL signaling pathways has been a promising strategy for treating osteoclast related bone diseases such as osteoporosis and aseptic prosthetic loosening. Schisantherin A (SA), a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been used as an antitussive, tonic, and sedative agent, but its effect on osteoclasts has been hitherto unknown. In the present study, SA was found to inhibit RANKL-induced osteoclast formation and bone resorption. The osteoclastic specific marker genes induced by RANKL including c-Src, SA inhibited OSCAR, cathepsin K and TRAP in a dose dependent manner. Further signal transduction studies revealed that SA down-regulate RANKL-induced nuclear factor-kappaB (NF-?B) signaling activation by suppressing the phosphorylation and degradation of I?B?, and subsequently preventing the NF-?B transcriptional activity. Moreover, SA also decreased the RANKL-induced MAPKs signaling pathway, including JNK and ERK1/2 posphorylation while had no obvious effects on p38 activation. Finally, SA suppressed the NF-?B and MAPKs subsequent gene expression of NFATc1 and c-Fos. In vivo studies, SA inhibited osteoclast function and exhibited bone protection effect in wear-particle-induced bone erosion model. Taken together, SA could attenuate osteoclast formation and wear particle-induced osteolysis by mediating RANKL signaling pathways. These data indicated that SA is a promising therapeutic natural compound for the treatment of osteoclast-related prosthesis loosening. PMID:24845381

He, Yi; Zhang, Qing; Shen, Yi; Chen, Xia; Zhou, Feng; Peng, Dan

2014-07-01

62

A compilation of charged-particle induced thermonuclear reaction rates  

NASA Astrophysics Data System (ADS)

Low-energy cross section data for 86 charged-particle induced reactions involving light (1 <=Z <=14), mostly stable, nuclei are compiled. The corresponding Maxwellian-averaged thermonuclear reaction rates of relevance in astrophysical plasmas at temperatures in the range from 106 K to 1010 K are calculated. These evaluations assume either that the target nuclei are in their ground state, or that the target states are thermally populated following a Maxwell-Boltzmann distribution, except in some cases involving isomeric states. Adopted values complemented with lower and upper limits of the rates are presented in tabular form. Analytical approximations to the adopted rates, as well as to the inverse/direct rate ratios, are provided.

Angulo, C.; Arnould, M.; Rayet, M.; Descouvemont, P.; Baye, D.; Leclercq-Willain, C.; Coc, A.; Barhoumi, S.; Aguer, P.; Rolfs, C.; Kunz, R.; Hammer, J. W.; Mayer, A.; Paradellis, T.; Kossionides, S.; Chronidou, C.; Spyrou, K.; degl'Innocenti, S.; Fiorentini, G.; Ricci, B.; Zavatarelli, S.; Providencia, C.; Wolters, H.; Soares, J.; Grama, C.; Rahighi, J.; Shotter, A.; Lamehi Rachti, M.

1999-08-01

63

Visual phenomena induced by cosmic rays and accelerated particles  

NASA Technical Reports Server (NTRS)

Experiments, conducted at cyclotrons together with observations by Apollo astronauts, suggest with little doubt that cosmic nuclei interacting with the visual apparatus cause the phenomenon of light flashes seen on translunar and transearth coast over the past four Apollo missions. Other experiments with high and low energy neutrons and a helium ion beam suggest that slow protons and helium ions with a stopping power greater than 10 to the 8th power eV/gram sq cm can cause the phenomenon in the dark adapted eye. It was demonstrated that charged particles induced by neutrons and helium ions can stimulate the visual apparatus. Some approaches to understanding the long term mission effects of galactic cosmic nuclei interacting with man and his nervous system are outlined.

Tobias, C. A.; Budinger, T. F.; Leith, J. T.; Mamoon, A.; Chapman, P. K.

1972-01-01

64

Dielectric response of particles in flowing media: the effect of shear-induced rotation on the variation in particle polarizability.  

PubMed

When particles in liquid suspensions flow through channels and pipes in a laminar fashion, the resulting parabolic velocity profile gives rise to shear, which induces the particles to rotate. If flowing suspensions containing dielectric particles are immersed in an external electric field, the anisotropic polarization induced in rotating nonspherical particles will vary with the orientation of the particle with respect to the external field; what results is an uncertainty in experimental measurements that involve particle polarization. The present study establishes the limits of this uncertainty and shows that departure from spherical symmetry in individual particles can lead to a significant overlap in measurements attempting to discriminate between particle subpopulations in suspensions. For example, the uncertainty in signal amplitude for a population of activated T-lymphocytes can be as high as 20%. Such concerns arise in applications like field-flow fractionation, dielectrophoretic sorting of particles, flow impedance measurements and cytometry, and, most recently, isodielectric separation, all of which are used to separate particles in a flow based on their dielectric response. This paper considers axisymmetric particles as the first departure from the approximation of spherical symmetry, shows how to calculate an estimate of the size of the population overlap, and suggests possible strategies to minimize it. PMID:21867228

Nikolic-Jaric, Marija; Ferrier, Graham A; Thomson, Douglas J; Bridges, Greg E; Freeman, Mark R

2011-07-01

65

Chloroquine-induced lipidosis mimicking Fabry disease  

Microsoft Academic Search

Intracellular accumulation of phospholipids may be a consequence of inherited or acquired metabolic disorders. In Fabry disease, deficiency of ?-galactosidase A results in storage of globotriasylceramide in numerous cells including endothelium, striated muscle (skeletal, cardiac), smooth muscle, and renal epithelium among others; the ultrastructural appearance of the inclusions is of whorled layers of alternating dense and pale material (‘zebra bodies’

Diana Albay; Sharon G Adler; Jaya Philipose; C C Calescibetta; Stephen G Romansky; Arthur H Cohen

2005-01-01

66

A high school gym-induced disease  

Microsoft Academic Search

Physical exercise may induce upper and lower airway symptoms such as rhinitis and asthma. Rhinitis symptoms are often neglected although runny nose and nasal congestion may interfere with performance of the affected individual. A detailed history regarding locality and time of symptoms is of most significance for taking the appropriate diagnostic measures and identifying, as in this case, an uncommon

C S Seitz; E B Bröcker; A Trautmann

2008-01-01

67

Induced pluripotent stem cells for modelling human diseases  

PubMed Central

Research into the pathophysiological mechanisms of human disease and the development of targeted therapies have been hindered by a lack of predictive disease models that can be experimentally manipulated in vitro. This review describes the current state of modelling human diseases with the use of human induced pluripotent stem (iPS) cell lines. To date, a variety of neurodegenerative diseases, haematopoietic disorders, metabolic conditions and cardiovascular pathologies have been captured in a Petri dish through reprogramming of patient cells into iPS cells followed by directed differentiation of disease-relevant cells and tissues. However, realizing the true promise of iPS cells for advancing our basic understanding of disease and ultimately providing novel cell-based therapies will require more refined protocols for generating the highly specialized cells affected by disease, coupled with strategies for drug discovery and cell transplantation. PMID:21727133

Unternaehrer, Juli J.; Daley, George Q.

2011-01-01

68

Contact nucleation of ice induced by biological aerosol particles  

NASA Astrophysics Data System (ADS)

The contact freezing of supercooled water droplets is one of the potentially important and the least understood heterogeneous mechanism of ice formation in tropospheric clouds. On the time scales of cloud lifetime the freezing of supercooled water droplets via contact mechanism may occur at higher temperature compared to the same IN immersed in the droplet. Recently we have developed an experimental method allowing for quantification of the freezing probability on a single droplet-particle collision event [1]. In the previous experimental studies with mineral dust (kaolinite, illite, feldspar, and hematite) we have been able to show that the rate of freezing at a given temperature is governed by the rate of droplet - particle collisions, and by the properties of the contact ice nuclei: its size, morphology and composition [1, 2]. In this contribution, we focus on the contact freezing efficiency of biological ice nuclei. We demonstrate that the contact freezing efficiency of Snomax (freeze-dried fragments of Pseudomonas syringae bacteria) follows very similar pattern observed in immersion freezing experiments, indicating that the INA-protein identified as the ice nucleation agent in the immersion freezing mode is also responsible for initiation of contact freezing. The same similarity is observed for contact freezing induced by semi-dry residual particles of birch pollen washing water, providing an evidence for the importance of organic macromolecules of biological origin for nucleation of atmospheric ice. Finally, our experiments show that mixing the birch pollen washing water with mineral dust (illite) significantly increases the IN efficiency of mineral dust and extends the temperature range of its IN activity. These findings suggest a possible route of multiplication of the effect of biological IN beyond observed atmospheric concentrations of pollen grains. [1] - Hoffmann, N., Kiselev, A., Rzesanke, D., Duft, D., and Leisner, T.: Experimental quantification of contact freezing in an electrodynamic balance Atmos. Meas. Tech., 6, 2373-2382, 2013. [2] - Hoffmann, N., Duft, D., Kiselev, A., and Leisner, T.: Contact freezing efficiency of mineral dust aerosols studied in an electrodynamic balance: quantitative size and temperature dependence for illite particles, Faraday Discuss., 2013.

Kiselev, Alexei; Hoffmann, Nadine; Schaefer, Manfred; Duft, Denis; Leisner, Thomas

2014-05-01

69

Using human induced pluripotent stem cells to treat retinal disease?  

PubMed Central

The eye is an ideal target for exploiting the potential of human induced pluripotent stem cell (hiPSC) technology in order to understand disease pathways and explore novel therapeutic strategies for inherited retinal disease. The aim of this article is to map the pathway from state-of-the art laboratory-based discoveries to realising the translational potential of this emerging technique. We describe the relevance and routes to establishing hiPSCs in selected models of human retinal disease. Additionally, we define pathways for applying hiPSC technology in treating currently incurable, progressive and blinding retinal disease. PMID:24104210

Borooah, S.; Phillips, M.J.; Bilican, B.; Wright, A.F.; Wilmut, I.; Chandran, S.; Gamm, D.; Dhillon, B.

2013-01-01

70

Management of drug-induced liver disease  

Microsoft Academic Search

The treatment and prevention of drug-induced liver injury starts with the recognition of hepatotoxicity at the earliest possible\\u000a time so that the suspected drug can be discontinued expeditiously. Both liver enzyme monitoring and vigilance for signs of\\u000a hypersensitivity involving the liver are useful strategies for many agents known to cause hepatocellular necrosis leading\\u000a to liver failure. Specific antidotes to prevent

Gustavo Marino; Hyman J. Zimmerman; James H. Lewis

2001-01-01

71

Coxsackievirus-induced acute neonatal central nervous system disease model  

PubMed Central

Coxsackievirus B (CVB) is a significant pathogen that causes pediatric central nervous system disease with acute syndromes commonly. The onset of its infection was abrupt, and after recovery there usually will be severe mental sequelae. The disease model for research was not established by the way of natural infection, although there are various investigations about the CVB-induced central nervous system (CNS) diseases. Thus, we have established an acute neonatal CNS disease mice model by CVB orally infecting. This model imitated the natural infection route and focuses the onset of CNS disease, inducing severe infection and lesion in the hippocampus and cortex regions, and the stability of the model was demonstrated. A pathology score system was developed for quantitative pathology analysis, which standardizes the CNS pathology analysis by statistics analysis. By this model, the track of CVB penetrating the blood brain barrier in vivo has been captured. One of the experimental strains CVB3/Macocy, as a new variant, was isolated, and its genomic RNA was cloned. According to its nucleotide sequence, we have characterized its genomic structure and defined its genotype. Based on the sequence, some mutations which do not change the CVB-induced CNS damage have been found. The model is an effective tool for studies on CVB-induced CNS diseases. PMID:24696707

Wang, Lulu; Dong, Changyuan; Chen, Dong-E; Song, Zhen

2014-01-01

72

Environmentally Induced Epigenetic Transgenerational Inheritance of Ovarian Disease  

PubMed Central

The actions of environmental toxicants and relevant mixtures in promoting the epigenetic transgenerational inheritance of ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1 and F3 generation progeny adult onset ovarian disease was assessed. Transgenerational disease phenotypes observed included an increase in cysts resembling human polycystic ovarian disease (PCO) and a decrease in the ovarian primordial follicle pool size resembling primary ovarian insufficiency (POI). The F3 generation granulosa cells were isolated and found to have a transgenerational effect on the transcriptome and epigenome (differential DNA methylation). Epigenetic biomarkers for environmental exposure and associated gene networks were identified. Epigenetic transgenerational inheritance of ovarian disease states was induced by all the different classes of environmental compounds, suggesting a role of environmental epigenetics in ovarian disease etiology. PMID:22570695

Nilsson, Eric; Larsen, Ginger; Manikkam, Mohan; Guerrero-Bosagna, Carlos; Savenkova, Marina I.; Skinner, Michael K.

2012-01-01

73

Environmentally induced epigenetic transgenerational inheritance of ovarian disease.  

PubMed

The actions of environmental toxicants and relevant mixtures in promoting the epigenetic transgenerational inheritance of ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1 and F3 generation progeny adult onset ovarian disease was assessed. Transgenerational disease phenotypes observed included an increase in cysts resembling human polycystic ovarian disease (PCO) and a decrease in the ovarian primordial follicle pool size resembling primary ovarian insufficiency (POI). The F3 generation granulosa cells were isolated and found to have a transgenerational effect on the transcriptome and epigenome (differential DNA methylation). Epigenetic biomarkers for environmental exposure and associated gene networks were identified. Epigenetic transgenerational inheritance of ovarian disease states was induced by all the different classes of environmental compounds, suggesting a role of environmental epigenetics in ovarian disease etiology. PMID:22570695

Nilsson, Eric; Larsen, Ginger; Manikkam, Mohan; Guerrero-Bosagna, Carlos; Savenkova, Marina I; Skinner, Michael K

2012-01-01

74

Time course of Newcastle disease virus-induced apoptotic pathways  

Microsoft Academic Search

Newcastle disease virus (NDV) causes economically significant Newcastle disease (ND) in almost all birds worldwide. Previous studies have shown that NDV induces caspase dependent apoptotic pathways in infected cells. In the present study, time course induction of apoptotic pathways in Vero cells is described. In NDV-infected cells, caspase-8 activity, percentage of cells showing TRAIL expression was higher at 24h p.i.

P. V. Ravindra; Ashok K. Tiwari; Barkha Ratta; Manish V. Bais; Uttara Chaturvedi; Sudesh Kumar Palia; Bhaskar Sharma; R. S. Chauhan

2009-01-01

75

Animal models of beryllium-induced lung disease  

Microsoft Academic Search

The Inhalation Toxicology Research Institute (ITRI) is conducting research to improve the understanding of chronic beryllium disease (CBD) and beryllium-induced lung cancer. Initial animal studies examined beagle dogs that inhaled BeO calcined at either 500 or 1000°C. At similar lung burdens, the 500°C BeO induced more severe and extensive granulomatous pneumonia, lymphocytic infiltration into the lung, and positive Be-specific lymphocyte

G. L. Finch; M. D. Hoover; F. F. Hahn

1996-01-01

76

ccsd00000796 Electric-eld induced capillary interaction of charged particles at a polar interface  

E-print Network

induced capillary interaction of charged particles at a polar interface. The algebraic tailsccsd­00000796 (version 1) : 28 Oct 2003 Electric-#12;eld induced capillary interaction of charged particles at a polar interface Lionel Foret and Alois Wurger CPMOH #3; , Universit#19;e Bordeaux 1, 351

77

Manipulation of quantum particles in rapidly oscillating potentials by inducing phase Armin Ridinger  

E-print Network

Manipulation of quantum particles in rapidly oscillating potentials by inducing phase hops Armin potential can be significantly manipulated by inducing phase hops, i.e., by instantaneously changing.65.Ge 03.75.Ss I. INTRODUCTION Potentials which oscillate rapidly relative to the mo- tion of particles

Paris-Sud XI, Université de

78

Particle image velocimetry and planar laser-induced fluorescence measurements on lobed jet mixing flows  

E-print Network

Particle image velocimetry and planar laser-induced fluorescence measurements on lobed jet mixing-induced ¯uores- cence (PLIF) and particle image velocimetry (PIV) were used to accomplish ¯ow visualisation character- istics downstream of a lobed nozzle/mixer systematically by using laser Doppler velocimetry (LDV

Hu, Hui

79

Calculation of Beam Loss Induced Particle Flux for CTF3 Matthew Wood  

E-print Network

Calculation of Beam Loss Induced Particle Flux for CTF3 Matthew Wood Northwestern University January 8, 2004 CTF3 Note 061 This research was partially supported by the Illinois Consortium to compute the beam loss induced particle ux outside the CTF3 accelerator vacuum chamber. GEANT 3

80

Immune Potentiation of Ultrafine Dietary Particles in Normal Subjects and Patients with Inflammatory Bowel Disease  

Microsoft Academic Search

Various specific and non-specific environmental factors have been associated with the induction and\\/or exacerbation of disease activity in patients with Crohn's disease and ulcerative colitis. One such factor is the potential role of ingested ultrafine particles. In fact, based on a Western diet, recent data suggest that more than 1012ultrafine particles are ingested per person every day. These microparticles have

J. J Powell; R. S. J Harvey; P Ashwood; R Wolstencroft; M. E Gershwin; R. P. H Thompson

2000-01-01

81

Quantifying Turbulence-Induced Segregation of Inertial Particles Enrico Calzavarini,1,* Massimo Cencini,2  

E-print Network

different flow structures: light particles (#12; > 1, e.g., air bubbles in water) preferentially concentrateQuantifying Turbulence-Induced Segregation of Inertial Particles Enrico Calzavarini,1,* Massimo 1, 44100 Ferrara, Italy (Received 5 February 2008; published 22 August 2008) Particles

Cencini, Massimo

82

3D Modeling of Shock-Induced Trapping of Solar Energetic Particles in the Earth's Magnetosphere  

E-print Network

3D Modeling of Shock-Induced Trapping of Solar Energetic Particles in the Earth's Magnetosphere M of Solar Energetic Particles (SEPs) in the inner magnetosphere around L=2-2.5 has been reported, including of solar energetic particles, both protons and heavy ions, with higher fluxes and harder spectra associated

Dartmouth College

83

Particle streak velocimetry and CH laser-induced fluorescence diagnostics in strained, premixed,  

E-print Network

Particle streak velocimetry and CH laser-induced fluorescence diagnostics in strained, premixed, 91125 Abstract We present the use of simultaneous Particle Streak Velocimetry (PSV) and CH Planar Laser Streak Velocimetry (PSV) [1­3], a tech- nique similar to particle tracking velocimetry [4], is used

Barr, Al

84

Virus-like particles associated with banana bunchy top disease contain small single-stranded DNA  

Microsoft Academic Search

Virus-like particles were purified from banana plants with banana bunchy top disease. These particles were isometric with a diameter of 18 to 20 nm and a density of 1.28 to 1-30 g\\/ml in caesium sulphate. Associated with these particles were an ssDNA of about 1 kb and one major protein of Mr 20100. DsDNA was synthe- sized from nucleic acid

Robert M. Harding; Thomas M. Burns; James L. Dale

1991-01-01

85

Electric-field induced capillary interaction of charged particles at a polar interface  

E-print Network

We study the electric-field induced capillary interaction of charged particles at a polar interface. The algebraic tails of the electrostatic pressure of each charge results in a deformation of the interface $u\\sim \\rho ^{-4}$. The resulting capillary interaction is repulsive and varies as $\\rho ^{-6}$ with the particle distance. As a consequence, electric-field induced capillary forces cannot be at the origin of the secondary minimum observed recently for charged PMMA particles at on oil-water interface.

Lionel Foret; Alois Würger

2003-10-28

86

Thermally relativistic flows induced by gravitational-force-free particle motion in curved spacetime  

SciTech Connect

Thermally relativistic flows in the early Universe can be characterized by the emergence of flows induced by gravitational-force-free particle motion in curved spacetime as well as induced by the gravitational force. In this paper, thermally relativistic flows induced by gravitational-force-free particle motion in curved spacetime are discussed on the basis of the general relativistic Boltzmann equation. As an object of analysis, we consider the flow from the static state inside the Schwarzschild radius of a thermally relativistic stuffed black hole induced by such motion. Analytical results obtained using the collisionless, nongravitational general relativistic Boltzmann equation reveal that the initial cluster is induced by gravitational-force-free particle motion. Numerical results obtained using the nongravitational general relativistic Anderson-Witting model confirm the presence of an initial cluster inside the thermally relativistic stuffed black hole, which is induced by gravitational-force-free particle motion.

Yano, Ryosuke; Suzuki, Kojiro; Kuroda, Hisayasu [Department of Advanced Energy, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Department of Advanced Energy, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Department of Information Technology, University of Ehime, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577 (Japan)

2009-12-15

87

Dynamics of magnetic particles near a surface: model and experiments on field-induced disaggregation.  

PubMed

Magnetic particles are widely used in biological research and bioanalytical applications. As the corresponding tools are progressively being miniaturized and integrated, the understanding of particle dynamics and the control of particles down to the level of single particles become important. Here, we describe a numerical model to simulate the dynamic behavior of ensembles of magnetic particles, taking account of magnetic interparticle interactions, interactions with the liquid medium and solid surfaces, as well as thermal diffusive motion of the particles. The model is verified using experimental data of magnetic field-induced disaggregation of magnetic particle clusters near a physical surface, wherein the magnetic field properties, particle size, cluster size, and cluster geometry were varied. Furthermore, the model clarifies how the cluster configuration, cluster alignment, magnitude of the field gradient, and the field repetition rate play a role in the particle disaggregation process. The simulation model will be very useful for further in silico studies on magnetic particle dynamics in biotechnological tools. PMID:24827250

van Reenen, A; Gao, Y; de Jong, A M; Hulsen, M A; den Toonder, J M J; Prins, M W J

2014-04-01

88

Electric Field Induced by Particles Accelerated in a Reconnecting Current Sheet  

Microsoft Academic Search

Particle acceleration in a reconnecting current sheet is studied by using 2D-3V particle-in-cell (PIC) simulation code which takes into account the electric and magnetic field induced by particles. The simulations are performed for a reduced particles mass ratio that allows to simulate simultaneously the dynamics of both electrons and protons. The size of a simulation region is chosen to be

T. Siversky; V. Zharkova

2008-01-01

89

Hypoxia and Hypoxia Inducible Factors: Diverse Roles in Liver Diseases  

PubMed Central

Hypoxia has been shown to have a role in the pathogenesis of several forms of liver disease. The Hypoxia Inducible Factors (HIFs) are a family of evolutionarily conserved transcriptional regulators that affect a homeostatic response to low oxygen tension and have been identified as key mediators of angiogenesis, inflammation, and metabolism. In this review, we summarize the evidence for a role of HIFs across a range of hepatic pathophysiology. We describe regulation of the hypoxia inducible factors and review investigations that demonstrate a role for HIFs in the development of liver fibrosis, activation of innate immune pathways, hepatocellular carcinoma, as well as other liver diseases in both human disease as well as murine models. PMID:22120903

Nath, Bharath; Szabo, Gyongyi

2011-01-01

90

A small nonhuman primate model for filovirus-induced disease.  

PubMed

Ebolavirus and Marburgvirus are members of the filovirus family and induce a fatal hemorrhagic disease in humans and nonhuman primates with 90% case fatality. To develop a small nonhuman primate model for filovirus disease, common marmosets (Callithrix jacchus) were intramuscularly inoculated with wild type Marburgvirus Musoke or Ebolavirus Zaire. The infection resulted in a systemic fatal disease with clinical and morphological features closely resembling human infection. Animals experienced weight loss, fever, high virus titers in tissue, thrombocytopenia, neutrophilia, high liver transaminases and phosphatases and disseminated intravascular coagulation. Evidence of a severe disseminated viral infection characterized principally by multifocal to coalescing hepatic necrosis was seen in EBOV animals. MARV-infected animals displayed only moderate fibrin deposition in the spleen. Lymphoid necrosis and lymphocytic depletion observed in spleen. These findings provide support for the use of the common marmoset as a small nonhuman primate model for filovirus induced hemorrhagic fever. PMID:21959017

Carrion, Ricardo; Ro, Youngtae; Hoosien, Kareema; Ticer, Anysha; Brasky, Kathy; de la Garza, Melissa; Mansfield, Keith; Patterson, Jean L

2011-11-25

91

Different particle determinants induce apoptosis and cytokine release in primary alveolar macrophage cultures  

PubMed Central

Background Particles are known to induce both cytokine release (MIP-2, TNF-?), a reduction in cell viability and an increased apoptosis in alveolar macrophages. To examine whether these responses are triggered by the same particle determinants, alveolar macrophages were exposed in vitro to mineral particles of different physical-chemical properties. Results The crystalline particles of the different stone types mylonite, gabbro, basalt, feldspar, quartz, hornfels and fine grain syenite porphyr (porphyr), with a relatively equal size distribution (? 10 ?m), but different chemical/mineral composition, all induced low and relatively similar levels of apoptosis. In contrast, mylonite and gabbro induced a marked MIP-2 response compared to the other particles. For particles of smaller size, quartz (? 2 ?m) seemed to induce a somewhat stronger apoptotic response than even smaller quartz (? 0.5 ?m) and larger quartz (? 10 ?m) in relation to surface area, and was more potent than hornfels and porphyr (? 2 ?m). The reduction in cell viability induced by quartz of the different sizes was roughly similar when adjusted to surface area. With respect to cytokines, the release was more marked after exposure to quartz ? 0.5 ?m than to quartz ? 2 ?m and ? 10 ?m. Furthermore, hornfels (? 2 ?m) was more potent than the corresponding hornfels (? 10 ?m) and quartz (? 2 ?m) to induce cytokine responses. Pre-treatment of hornfels and quartz particles ? 2 ?m with aluminium lactate, to diminish the surface reactivity, did significantly reduce the MIP-2 response to hornfels. In contrast, the apoptotic responses to the particles were not affected. Conclusion These results indicate that different determinants of mineral/stone particles are critical for inducing cytokine responses, reduction in cell viability and apoptosis in alveolar macrophages. The data suggest that the particle surface reactivity was critical for cytokine responses, but contributed less to cell death for the types of particles tested. The size-dependent variations, specially in cytokine release, seem not to be explained only by particle surface area. PMID:16774673

Refsnes, Magne; Hetland, Ragna B; ?vrevik, Johan; Sundf?r, Idunn; Schwarze, Per E; Lag, Marit

2006-01-01

92

Toxicogenomic analysis of the particle dose- and size-response relationship of silica particles-induced toxicity in mice  

NASA Astrophysics Data System (ADS)

This study investigated the relationship between particle size and toxicity of silica particles (SP) with diameters of 30, 70, and 300 nm, which is essential to the safe design and application of SP. Data obtained from histopathological examinations suggested that SP of these sizes can all induce acute inflammation in the liver. In vivo imaging showed that intravenously administrated SP are mainly present in the liver, spleen and intestinal tract. Interestingly, in gene expression analysis, the cellular response pathways activated in the liver are predominantly conserved independently of particle dose when the same size SP are administered or are conserved independently of particle size, surface area and particle number when nano- or submicro-sized SP are administered at their toxic doses. Meanwhile, integrated analysis of transcriptomics, previous metabonomics and conventional toxicological results support the view that SP can result in inflammatory and oxidative stress, generate mitochondrial dysfunction, and eventually cause hepatocyte necrosis by neutrophil-mediated liver injury.

Lu, Xiaoyan; Jin, Tingting; Jin, Yachao; Wu, Leihong; Hu, Bin; Tian, Yu; Fan, Xiaohui

2013-01-01

93

Co-Cr-Mo Alloy Particles Induce Tumor Necrosis Factor Alpha Production in MLO-Y4 Osteocytes: A Role for Osteocytes in Particle Induced Inflammation  

PubMed Central

Wear debris-induced osteolysis is purportedly the limiting problem affecting the long term results of joint arthroplasty. Pathogenic effects of wear debris in peri-implant cells such as macrophages, osteoblasts and osteoclasts have been well studied. In contrast, the affects of wear-debris on osteocytes, which make up over 90% of all bone cells, remains unknown. We hypothesized that metal implant debris can induce the proinflammatory response in osteocytes. This study demonstrated the effects of cobalt-chromium-molybdenum alloy (Co-Cr-Mo) particles on a well-characterized MLO-Y4 osteocyte cell line. Co-Cr-Mo alloy particle treatment significantly (p<0.05) up-regulated tumor necrosis factor alpha (TNF?) gene expression after 3 and 6 hr and TNF? protein production after 24 hr, but down-regulated interleukin-6 (IL-6) gene expression after 6 hr. Co-Cr-Mo alloy particle treatment also induced osteocyte apoptosis after 24 hr. This apoptotic effect was partially (40%) dependent on TNF?. Therefore, our results suggest that osteocytes play a role in particle induced inflammation and bone resorption following total hip arthroplasty by inducing pro-inflammatory cytokines and inducing osteocyte apoptosis. PMID:19497395

Kanaji, Arihiko; Caicedo, Marco S.; Virdi, Amarjit S.; Sumner, D. Rick; Hallab, Nadim J.; Sena, Kotaro

2009-01-01

94

Development of disease-resistant rice using regulatory components of induced disease resistance  

PubMed Central

Infectious diseases cause huge crop losses annually. In response to pathogen attacks, plants activate defense systems that are mediated through various signaling pathways. The salicylic acid (SA) signaling pathway is the most powerful of these pathways. Several regulatory components of the SA signaling pathway have been identified, and are potential targets for genetic manipulation of plants’ disease resistance. However, the resistance associated with these regulatory components is often accompanied by fitness costs; that is, negative effects on plant growth and crop yield. Chemical defense inducers, such as benzothiadiazole and probenazole, act on the SA pathway and induce strong resistance to various pathogens without major fitness costs, owing to their ‘priming effect.’ Studies on how benzothiadiazole induces disease resistance in rice have identified WRKY45, a key transcription factor in the branched SA pathway, and OsNPR1/NH1. Rice plants overexpressing WRKY45 were extremely resistant to rice blast disease caused by the fungus Magnaporthe oryzae and bacterial leaf blight disease caused by Xanthomonas oryzae pv. oryzae (Xoo), the two major rice diseases. Disease resistance is often accompanied by fitness costs; however, WRKY45 overexpression imposed relatively small fitness costs on rice because of its priming effect. This priming effect was similar to that of chemical defense inducers, although the fitness costs were amplified by some environmental factors. WRKY45 is degraded by the ubiquitin–proteasome system, and the dual role of this degradation partly explains the priming effect. The synergistic interaction between SA and cytokinin signaling that activates WRKY45 also likely contributes to the priming effect. With a main focus on these studies, I review the current knowledge of SA-pathway-dependent defense in rice by comparing it with that in Arabidopsis, and discuss potential strategies to develop disease-resistant rice using signaling components.

Takatsuji, Hiroshi

2014-01-01

95

Successful crizotinib rechallenge after crizotinib-induced interstitial lung disease.  

PubMed

We report the case of a 70-year-old Japanese male diagnosed with advanced lung adenocarcinoma harboring the echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase fusion gene. As soon as crizotinib was administered, tumor shrank immediately. On Day 25, he developed interstitial lung disease. Bronchoalveolar lavage fluid analysis demonstrated elevated lymphocytes fractionation. A drug lymphocyte stimulating test for crizotinib with the bronchoalveolar lavage lymphocytes was negative. Crizotinib administration was discontinued, but a life-threatening flare of tumor growth occurred. Since there was no alternative treatment for the lung cancer, we restarted crizotinib in combination with prednisolone. The patient experienced neither disease progression nor recurrence of interstitial lung disease at 6 months. In cases in which no alternate treatment is known, crizotinib retreatment combined with steroid therapy after crizotinib-induced interstitial lung disease could be considered after a careful consideration of the potential risks and benefits. PMID:24872405

Tachihara, Motoko; Kobayashi, Kazuyuki; Ishikawa, Yumiko; Hori, Suya; Tamura, Daisuke; Otera, Hiroshi; Funada, Yasuhiro; Nishimura, Yoshihiro

2014-08-01

96

Misinterpretation of NSAID-induced Colopathy as Crohn's disease.  

PubMed

Although NSAID-induced colonopathy characterised by erosions, ulcers, strictures and diaphragms has been known for quite some time, it is not infrequently misinterpreted endoscopically and histologically as Crohn's disease. This is exemplified by the present case history of a 39-year-old man with bloody diarrhoea and a stenosis in the transverse colon that was histologically interpreted as "consistent with Crohn's disease". Treatment with glucocorticoids, however, merely gave rise to adverse reactions. After surgical treatment of the stenosis, the episodes of bloody diarrhoea persisted, and endoscopy continued to reveal erosions and ulcers in the transverse colon. Changing treatment to azathioprine also failed to produce any positive response, merely causing side effects. Subsequent evaluation of the histological specimens by a consultant pathologist turned up the tentative diagnosis of NSAID-induced colonopathy. An analysis of the patient's medical history revealed that he was suffering from Bechterew's disease, for which he had long been taking diclofenac. This case history is a good example of the fact that NSAID-induced enterocolopathy is still too poorly recognised among internists, gastroenterologists and pathologists, and, on the basis of the discontinuous endoscopic and histological findings, is often misinterpreted as Crohn's disease. PMID:20140840

Stolte, M; Hartmann, F O

2010-04-01

97

Interleukin-35 induces regulatory B cells that suppress autoimmune disease.  

PubMed

Interleukin-10 (IL-10)-producing regulatory B (Breg) cells suppress autoimmune disease, and increased numbers of Breg cells prevent host defense to infection and promote tumor growth and metastasis by converting resting CD4(+) T cells to regulatory T (Treg) cells. The mechanisms mediating the induction and development of Breg cells remain unclear. Here we show that IL-35 induces Breg cells and promotes their conversion to a Breg subset that produces IL-35 as well as IL-10. Treatment of mice with IL-35 conferred protection from experimental autoimmune uveitis (EAU), and mice lacking IL-35 (p35 knockout (KO) mice) or defective in IL-35 signaling (IL-12R?2 KO mice) produced less Breg cells endogenously or after treatment with IL-35 and developed severe uveitis. Adoptive transfer of Breg cells induced by recombinant IL-35 suppressed EAU when transferred to mice with established disease, inhibiting pathogenic T helper type 17 (TH17) and TH1 cells while promoting Treg cell expansion. In B cells, IL-35 activates STAT1 and STAT3 through the IL-35 receptor comprising the IL-12R?2 and IL-27R? subunits. As IL-35 also induced the conversion of human B cells into Breg cells, these findings suggest that IL-35 may be used to induce autologous Breg and IL-35(+) Breg cells and treat autoimmune and inflammatory disease. PMID:24743305

Wang, Ren-Xi; Yu, Cheng-Rong; Dambuza, Ivy M; Mahdi, Rashid M; Dolinska, Monika B; Sergeev, Yuri V; Wingfield, Paul T; Kim, Sung-Hye; Egwuagu, Charles E

2014-06-01

98

Passing particle toroidal precession induced by electric field in a tokamak  

SciTech Connect

Characteristics of a rotation of passing particles in a tokamak with radial electric field are calculated. The expression for time-averaged toroidal velocity of the passing particle induced by the electric field is derived. The electric-field-induced additive to the toroidal velocity of the passing particle appears to be much smaller than the velocity of the electric drift calculated for the poloidal magnetic field typical for the trapped particle. This quantity can even have the different sign depending on the azimuthal position of the particle starting point. The unified approach for the calculation of the bounce period and of the time-averaged toroidal velocity of both trapped and passing particles in the whole volume of plasma column is presented. The results are obtained analytically and are confirmed by 3D numerical calculations of the trajectories of charged particles.

Andreev, V. V. [Peoples' Friendship University of Russia, Ordzhonikidze St. 3, Moscow 117198 (Russian Federation)] [Peoples' Friendship University of Russia, Ordzhonikidze St. 3, Moscow 117198 (Russian Federation); Ilgisonis, V. I.; Sorokina, E. A. [Peoples' Friendship University of Russia, Ordzhonikidze St. 3, Moscow 117198 (Russian Federation) [Peoples' Friendship University of Russia, Ordzhonikidze St. 3, Moscow 117198 (Russian Federation); NRC “Kurchatov Institute”, Kurchatov Sq. 1, Moscow 123182 (Russian Federation)

2013-12-15

99

Adenovirus Particles that Display the Plasmodium falciparum Circumsporozoite Protein NANP Repeat Induce Sporozoite-Neutralizing Antibodies in Mice  

PubMed Central

Adenovirus particles can be engineered to display exogenous peptides on their surfaces by modification of viral capsid proteins, and particles that display pathogen-derived peptides can induce protective immunity. We constructed viable recombinant adenoviruses that display B-cell epitopes from the Plasmodium falciparum circumsporozoite protein (PfCSP) in the major adenovirus capsid protein, hexon. Recombinants induced high-titer antibodies against CSP when injected intraperitoneally into mice. Serum obtained from immunized mice recognized both recombinant PfCSP protein and P. falciparum sporozoites, and neutralized P. falciparum sporozoites in vitro. Replicating adenovirus vaccines have provided economical protection against adenovirus disease for over three decades. The recombinants described here may provide a path to an affordable malaria vaccine in the developing world. PMID:21199707

Palma, Christopher; Overstreet, Michael G.; Guedon, Jean-Marc; Hoiczyk, Egbert; Ward, Cameron; Karen, Kasey A.; Zavala, Fidel; Ketner, Gary

2011-01-01

100

Temperature induced formation of particle coated non-spherical droplets.  

PubMed

Herein we offer a simple method to produce non-spherical emulsion droplets stabilized by freshly formed Mg(OH)(2) nanoparticles (MPs). The non-spherical degree of droplets as a function of experiment conditions was investiged and the origins of the presence of non-spherical droplets were discussed. The results of optical microscope images show that stable spherical droplets can be fused into non-spherical at given aging temperature. It is also recognized that particle concentration, oil/water ratio and aging time significantly affect droplet fusion and excess particles that are not adsorbed on the oil/water interface are helpful in restraining droplet fusion. Based on the TEM, XRD and Fluorescence confocal microscopy results, the origins of droplet fusion are inferred from the presence of vacant holes in the particle layer. Because of Oswald ripening, particles on droplet surfaces grow larger than the freshly precipitated ones under a given aging temperature. The growth of particles results in the reduction of total cover area of particle layer and thus creates vacant holes in the particle layer which would cause partial coalescence of droplets once they collide. Thus, these findings can offer a simple alternative to obtain a large amount of non-spherical emulsion droplets but also can help the preparation of non-spherical colloid particles. PMID:21507415

Tan, Junjun; Zhang, Mei; Wang, Jun; Xu, Jian; Sun, Dejun

2011-07-01

101

Photon and Electron induced Particle Production on Nuclei  

E-print Network

We discuss several particle production reactions on nuclei within a BUU transport model. After a short presentation of the model we show our results for the transparency ratio for the nucleon knock-out reaction in different nuclei. The influence of the nucleon spectral function on subthreshold particle production is discussed.

J. Lehr; U. Mosel

2001-08-08

102

Asymmetry-induced particle drift in a rotating flow  

Microsoft Academic Search

We report on an intriguing phenomenon taking place in a liquid rotating around a fixed horizontal axis. Under suitable conditions, bubbles and particles are observed to drift along the axis of rotation maintaining a constant distance from it and a constant angle of elevation above the horizontal. Absence of fore-aft symmetry of the bubble or particle shape is a prerequisite

J. J. Bluemink; E. A. van Nierop; S. Luther; N. G. Deen; J. Magnaudet; A. Prosperetti; D. Lohse

2005-01-01

103

Modeling three-dimensional constituent particle microstructure and particle-induced pitting corrosion in rolled aluminum alloys  

NASA Astrophysics Data System (ADS)

In the last two decades there has been a surge in research surrounding the corrosion and fatigue properties of high strength aluminum alloys aimed at extending the service life of commercial and military aircraft. It is recognized that corrosion damage in aluminum alloys is the direct result of local galvanic coupling between constituent particles and the metal matrix. As the corrosion pit associated with an individual particle grows it often coalesces with adjacent pits and can expose subsurface constituent particles, perpetuating the evolution of corrosion damage. As a result, heavily clustered groups of constituent particles tend to foster the most severe corrosion pits, and the morphology of these multi-particle pits has been found to exhibit a strong correlation with that of the instigating particle cluster. Severe pits are particularly detrimental to the fatigue life of aluminum components, nucleating fatigue cracks and circumventing the low growth rates of the short crack regime. The goal of this work is to provide a tool for predicting the evolution of particle-induced corrosion damage in rolled aluminum alloys by way of numerical simulation techniques. A three-dimensional constituent particle microstructure model is proposed. This model is used to generate statistically representative three-dimensional constituent particle microstructure from two-dimensional, orthogonal sections. The temporal evolution of severe corrosion damage for a particular constituent particle microstructure can then be simulated via a particle-based corrosion model. This corrosion simulation algorithm makes it possible to perform material-specific, numerical corrosion analyses and represents a significant advancement in the quest to develop reliable and cost efficient life-cycle prediction methods for aging airframes.

Cullin, Matthew Joseph

104

[Particle pollution effects on the risk of cardiovascular diseases].  

PubMed

The effects of air pollution on health are quite well-documented and the influence of particulate pollution on morbidity and mortality from myocardial infarction and stroke is increasingly evident. The objective of this literature review is to identify and synthesize articles on the impact of air pollution by PM10 and PM2.5 of myocardial infarction and stroke. A total of 14 studies were reported on the effects of PM10 and five on the effects of PM2.5. Nine out of 14 studies for PM10 and two studies of five for PM2.5 have found a significant association with myocardial infarction and/or stroke. Particle composition according to location, study period and population must be considered in interpreting the results on the health effects of air pollution. The integration of these elements is important for decision making in tune with social and economic conditions specific to each environment. PMID:24041338

Massamba, V K; Coppieters, Y; Mercier, G; Collart, P; Levêque, A

2014-02-01

105

Piribedil-induced sleep attacks in Parkinson's disease.  

PubMed

'Sleep attacks', episodes of sudden onset of sleep without any prodromal symptoms, were initially described in patients with Parkinson's disease (PD) taking the newer dopamine agonists pramipexole and ropinirole. Piribedil, a nonergot agonist with both D2 and D3 agonist action, is an effective antiparkinsonian medication. However, there are very few reports of Piribedil-induced sleep attacks in PD. Among 50 PD patients seen at our Movement Disorder Clinic who had recently taken Piribedil, we identified three (6%) who satisfied the clinical description of sleep attacks. Here we provide details of the clinical characteristics of Piribedil-induced sleep attacks in these PD patients. PMID:12588638

Tan, E K

2003-02-01

106

Aloe vera Induced Biomimetic Assemblage of Nucleobase into Nanosized Particles  

PubMed Central

Aim Biomimetic nano-assembly formation offers a convenient and bio friendly approach to fabricate complex structures from simple components with sub-nanometer precision. Recently, biomimetic (employing microorganism/plants) synthesis of metal and inorganic materials nano-particles has emerged as a simple and viable strategy. In the present study, we have extended biological synthesis of nano-particles to organic molecules, namely the anticancer agent 5-fluorouracil (5-FU), using Aloe vera leaf extract. Methodology The 5-FU nano- particles synthesized by using Aloe vera leaf extract were characterized by UV, FT-IR and fluorescence spectroscopic techniques. The size and shape of the synthesized nanoparticles were determined by TEM, while crystalline nature of 5-FU particles was established by X-ray diffraction study. The cytotoxic effects of 5-FU nanoparticles were assessed against HT-29 and Caco-2 (human adenocarcinoma colorectal) cell lines. Results Transmission electron microscopy and atomic force microscopic techniques confirmed nano-size of the synthesized particles. Importantly, the nano-assembled 5-FU retained its anticancer action against various cancerous cell lines. Conclusion In the present study, we have explored the potential of biomimetic synthesis of nanoparticles employing organic molecules with the hope that such developments will be helpful to introduce novel nano-particle formulations that will not only be more effective but would also be devoid of nano-particle associated putative toxicity constraints. PMID:22403622

Chauhan, Arun; Zubair, Swaleha; Sherwani, Asif; Owais, Mohammad

2012-01-01

107

Time course of Newcastle disease virus-induced apoptotic pathways.  

PubMed

Newcastle disease virus (NDV) causes economically significant Newcastle disease (ND) in almost all birds worldwide. Previous studies have shown that NDV induces caspase dependent apoptotic pathways in infected cells. In the present study, time course induction of apoptotic pathways in Vero cells is described. In NDV-infected cells, caspase-8 activity, percentage of cells showing TRAIL expression was higher at 24h p.i. (post-infection) compared to 48 h p.i. In contrast, caspase-9 activity, efflux of cytochrome c, loss of mitochondrial membrane potential was higher at 48 h compared to 24h p.i. The caspase-3 activity was high both times. Based on these results, it was concluded that at 24h p.i., NDV induces apoptosis through extrinsic apoptotic pathway while at 48 h p.i. predominantly through intrinsic apoptotic pathway. PMID:19501124

Ravindra, P V; Tiwari, Ashok K; Ratta, Barkha; Bais, Manish V; Chaturvedi, Uttara; Palia, Sudesh Kumar; Sharma, Bhaskar; Chauhan, R S

2009-09-01

108

Stress-Induced Blood Pressure Reactivity and Silent Cerebrovascular Disease  

Microsoft Academic Search

Background and Purpose—Exaggerated blood pressure (BP) responses to mental stress, an index of autonomic dysregulation, have been related to enhanced risk for stroke. This study examined cross-sectional relations of stress-induced BP reactivity to silent cerebrovascular disease assessed by magnetic resonance imaging (MRI) in healthy older adults. Methods—Sixty-seven nondemented, community-dwelling older adults (ages 55 to 81; 75% male) free of major

Shari R. Waldstein; Eliot L. Siegel; David Lefkowitz; Karl J. Maier; Jessica R. Pelletier Brown; Abraham M. Obuchowski; Leslie I. Katzel

2010-01-01

109

DIESEL EXHAUST PARTICLES INDUCE ABERRANT ALVEOLAR EPITHELIAL DIRECTED CELL MOVEMENT BY DISRUPTION OF POLARITY MECHANISMS  

EPA Science Inventory

Disruption of the respiratory epithelium contributes to the progression of a variety of respiratory diseases that are aggravated by exposure to air pollutants, specifically traffic-based pollutants such as diesel exhaust particles (DEP). Recognizing that lung repair following inj...

110

Characterization of nuclear physics targets using Rutherford backscattering and particle induced x-ray emission  

E-print Network

Rutherford backscattering and particle induced x-ray emission have been utilized to precisely characterize targets used in nuclear fission experiments. The method allows for a fast and non destructive determination of target thickness, homogeneity and element composition.

Th. Rubehn; G. J. Wozniak; L. Phair; L. G. Moretto; Kin M. Yu

1996-09-23

111

Capillary tube wetting induced by particles: towards armoured bubbles tailoring.  

PubMed

In this paper, we report on the strongly modified dynamics of a liquid finger pushed inside a capillary tube, when partially wettable particles are lying on the walls. Particles promote the appearance of new regimes and enable the tailored synthesis of bubbles encapsulated in a monolayer of particles (so-called "armoured bubbles"). This remarkable behavior arises due to the collection of particles at the air-liquid interface, which modify the global energy balance and stabilize the interface. Armoured-bubbles are of primary interest in industrial processes since they display increased stability, interfacial rigidity and can even sustain non-spherical shapes. This work opens perspective for a low cost bubbles-on-demand technology enabling the synthesis of armoured bubbles with specific sizes, shapes and composition. PMID:25271805

Zoueshtiagh, Farzam; Baudoin, Michael; Guerrin, David

2014-12-21

112

Asymmetry-induced particle drift in a rotating flow  

NASA Astrophysics Data System (ADS)

We report on an intriguing phenomenon taking place in a liquid rotating around a fixed horizontal axis. Under suitable conditions, bubbles and particles are observed to drift along the axis of rotation maintaining a constant distance from it and a constant angle of elevation above the horizontal. Absence of fore-aft symmetry of the bubble or particle shape is a prerequisite for this phenomenon. For bubbles, this requires a volume sufficiently large for surface-tension effects to be small and large deformations to be possible. Particle image velocimetry and flow visualization suggest that the wake does not play a role. The dependence on bubble radius, particle shape, liquid viscosity, and speed of rotation is investigated.

Bluemink, J. J.; van Nierop, E. A.; Luther, S.; Deen, N. G.; Magnaudet, J.; Prosperetti, A.; Lohse, D.

2005-07-01

113

Aging induced changes on NEXAFS fingerprints in individual combustion particles  

NASA Astrophysics Data System (ADS)

Soot particles can significantly influence the Earth's climate by absorbing and scattering solar radiation as well as by acting as cloud condensation nuclei. However, despite their environmental (as well as economic and political) importance, the way these properties are affected by atmospheric processing of the combustion exhaust gases is still a subject of discussion. In this work, individual soot particles emitted from two different vehicles, a EURO 2 transporter, a EURO 3 passenger car, and a wood stove were investigated on a single-particle basis. The emitted exhaust, including the particulate and the gas phase, was processed in a smog chamber with artificial solar radiation. Single particle specimens of both unprocessed and aged soot were characterized using near edge X-ray absorption fine structure spectroscopy (NEXAFS) and scanning electron microscopy. Comparison of NEXAFS spectra from the unprocessed particles and those resulting from exhaust photooxidation in the chamber revealed changes in the carbon functional group content. For the wood stove emissions, these changes were minor, related to the relatively mild oxidation conditions. For the EURO 2 transporter emissions, the most apparent change was that of carboxylic carbon from oxidized organic compounds condensing on the primary soot particles. For the EURO 3 car emissions oxidation of primary soot particles upon photochemical aging has likely contributed as well. Overall, the changes in the NEXAFS fingerprints were in qualitative agreement with data from an aerosol mass spectrometer. Furthermore, by taking full advantage of our in situ microreactor concept, we show that the soot particles from all three combustion sources changed their ability to take up water under humid conditions upon photochemical aging of the exhaust. Due to the selectivity and sensitivity of the NEXAFS technique for the water mass, also small amounts of water taken up into the internal voids of agglomerated particles could be detected. Because such small amounts of water uptake do not lead to measurable changes in particle diameter, it may remain beyond the limits of volume growth measurements, especially for larger agglomerated particles.

Zelenay, V.; Mooser, R.; Tritscher, T.; K?epelová, A.; Heringa, M. F.; Chirico, R.; Prévôt, A. S. H.; Weingartner, E.; Baltensperger, U.; Dommen, J.; Watts, B.; Raabe, J.; Huthwelker, T.; Ammann, M.

2011-11-01

114

Ultrafine particles from diesel vehicle emissions at different driving cycles induce differential vascular pro-inflammatory responses: Implication of chemical components and NF-?B signaling  

Microsoft Academic Search

BACKGROUND: Epidemiological evidence supports the association between exposure to ambient particulate matter (PM) and cardiovascular diseases. Chronic exposure to ultrafine particles (UFP; Dp <100 nm) is reported to promote atherosclerosis in ApoE knockout mice. Atherogenesis-prone factors induce endothelial dysfunction that contributes to the initiation and progression of atherosclerosis. We previously demonstrated that UFP induced oxidative stress via c-Jun N-terminal Kinases

Rongsong Li; Zhi Ning; Rohit Majumdar; Jeffery Cui; Wakako Takabe; Nelson Jen; Constantinos Sioutas; Tzung Hsiai

2010-01-01

115

Mechanism of bubble coalescence induced by surfactant covered antifoam particles.  

PubMed

Mechanism of inter-bubble coalescence by an aqueous fatty alcohol particle suspension antifoam containing a nonionic surfactant has been investigated. By observing visually two colliding air bubbles in a liquid pool in the presence of the antifoam, a four-step mechanism is identified. The role of the surfactant in the antifoam is, for the first time, proposed. A surface tension gradient due to the local surfactant concentration difference enables a surfactant laden hydrophobic particle located on bubble surface to move from the periphery of a liquid film between two colliding air bubbles to their region of contact. Drop volume tensiometry and macroscopic foam column experiments are used to further prove this observation. Subsequently, the particle bridges and dewets the bubbles resulting in film rupture. The rate of drainage of the liquid film depends on the particle hydrophobicity, which necessitates complete surfactant desorption from particle surface. This is corroborated experimentally by Wilhelmy plate tensiometry. In addition, cryo-scanning electron and atomic force microscopy are used to determine the particle shape and the force for its entry into the bubble. PMID:19726048

Joshi, K S; Baumann, A; Jeelani, S A K; Blickenstorfer, C; Naegeli, I; Windhab, E J

2009-11-15

116

A new disease: pregnancy-induced sudden sensorineural hearing loss?  

PubMed

Sudden sensorineural hearing loss (SSNHL) may occur during pregnancy, but its prevalence is very low. It is conjectured that SSNHL is closely related to the changes in the cardiovascular system, hematological system, endocrine system, and/or some other systems due to pregnancy. These changes possibly evoke disorders of cochlear circulation or cochlear fluid homeostasis leading to SSNHL. Two SSNHL cases were observed in our clinic, and their clinical features were analyzed. In one patient the SSNHL was likely to be related to the disturbance of cochlear fluid homestasis and in the other it might be induced by some disorders in cochlear circulation. Based on their distinct clinic profiles, we defined a new disease, called "pregnancy-induced sudden sensorineural hearing loss," similar to the definition of "pregnancy-induced hypertension." This study also deepened our understanding of the etiology of SSNHL. PMID:21426273

Hou, Zhi-Qiang; Wang, Qiu-Ju

2011-07-01

117

The Role of TLR and Chemokine in Wear Particle-Induced Aseptic Loosening  

PubMed Central

Wear particle-induced periprosthetic osteolysis remains the principal cause of aseptic loosening of orthopaedic implants. Monocytes/macrophages phagocytose wear particles and release cytokines that induce inflammatory response. This response promotes osteoclast differentiation and osteolysis. The precise mechanisms by which wear particles are recognized and induce the accumulation of inflammatory cells in the periprosthetic tissue have not been fully elucidated. Recent studies have shown that toll-like receptors (TLRs) contribute to the cellular interaction with wear particles. Wear particles are recognized by monocytes/macrophages through TLRs coupled with the adaptor protein MyD88. After the initial interaction, wear particles induce both local and systemic migration of monocytes/macrophages to the periprosthetic region. The cellular migration is mediated through chemokines including interleukin-8, macrophage chemotactic protein-1, and macrophage inhibitory protein-1 in the periprosthetic tissues. Interfering with chemokine-receptor axis can inhibit cellular migration and inflammatory response. This paper highlights recent advances in TLR, and chemokine participated in the pathogenesis of aseptic loosening. A comprehensive understanding of the recognition and migration mechanism is critical to the development of measures that prevent wear particle-induced aseptic loosening of orthopaedic implants. PMID:23193363

Gu, Qiaoli; Shi, Qin; Yang, Huilin

2012-01-01

118

Intercalation-Induced Stress and Heat Generation within Single Lithium-Ion Battery Cathode Particles  

E-print Network

-induced stress and heat generation inside Li-ion battery cathode LiMn2O4 particles under potentiodynamic control particles, in improving battery performance when stress and heat generation are the only factors considered. Excessive heat generation in Li batteries, resulting in thermal runaway, results in complete cell failure

Sastry, Ann Marie

119

Analysis on the Self-Induced Sloshing using Particle Image Velocimetry  

E-print Network

Analysis on the Self-Induced Sloshing using Particle Image Velocimetry Koji OKAMOTO, Souichi SAEKI Image Velocimetry. Using the double pulsed Nd:YAG Laser and high resolution CCD camera, phase averaged in the smaller vessel using the high resolution Particle Image Velocimetry technique. While the vessel size

Hu, Hui

120

Electric field-induced motion of solid particles in two-dimensional fluids  

Microsoft Academic Search

Electric field induced motion of spherical and cylindrical glass particles were studied in a smectic A liquid crystal octyl cyanobiphenyl (8CB) medium. The particles were dispersed in the smectic A medium, sandwiched between to glass plates with conductive inner surfaces. Under DC fields the smectic layers become parallel to the glass substrates. Such configuration corresponds to a two dimensional isotropic

Antal Jackli; Guangxun Liao; Jack R. Kelly

2004-01-01

121

Walking-induced particle resuspension in indoor environments  

NASA Astrophysics Data System (ADS)

Resuspension of particles indoors increases the risk of consequent exposure through inhalation and non-dietary ingestion. Studies have been conducted to characterize indoor particle resuspension but results do not always agree, and there are still many open questions in this field. This paper reviews the recent research of indoor resuspension and summarizes findings to answer six critical questions: 1) How does the resuspension sources compared to other indoor sources; 2) How is resuspension determined and how does the resuspension measure change as a function of particle size; 3) What are the primary resuspension mechanisms; 4) What are the factors affecting resuspension; 5) What are the knowledge gaps and future research directions in this area; and 6) How can what we know about resuspension guide better exposure mitigation strategies? From synthesized results, we conclude that resuspension is an important source for indoor particulate matter, compared with other indoor sources. Among all existing quantification terms of resuspension, resuspension fraction has the least variation in its estimates by explicitly defining surface loading and walking frequency, and thus is recommended to be adopted in future research over other terms. Resuspension increases with particle size in the range of 0.7-10 ?m, although differences exist in resuspension estimates by orders of magnitude. The primary mechanism of particle resuspension involves rolling detachment, and the adhesive forces can be greatly reduced by microscopic surface roughness. Particle resuspension is by nature complicated, affected by various factors and their interactions. There are still many open questions to be answered to achieve an understanding of resuspension fundamentals. Given the complex and multidisciplinary nature of resuspension, understanding indoor particle resuspension behavior requires cross-disciplinary participation from experts in aerosol science, textile science, surface chemistry, electrostatics, and fluid mechanics.

Qian, Jing; Peccia, Jordan; Ferro, Andrea R.

2014-06-01

122

TURBULENCE-INDUCED RELATIVE VELOCITY OF DUST PARTICLES. I. IDENTICAL PARTICLES  

SciTech Connect

We study the relative velocity of inertial particles suspended in turbulent flows and discuss implications for dust particle collisions in protoplanetary disks. We simulate a weakly compressible turbulent flow, evolving 14 particle species with friction timescale, ?{sub p}, covering the entire range of scales in the flow. The particle Stokes numbers, St, measuring the ratio of ?{sub p} to the Kolmogorov timescale, are in the range 0.1 ?< St ?< 800. Using simulation results, we show that the model by Pan and Padoan gives satisfactory predictions for the rms relative velocity between identical particles. The probability distribution function (PDF) of the relative velocity is found to be highly non-Gaussian. The PDF tails are well described by a 4/3 stretched exponential function for particles with ?{sub p} ? 1-2 T{sub L}, where T{sub L} is the Lagrangian correlation timescale, consistent with a prediction based on PP10. The PDF approaches Gaussian only for very large particles with ?{sub p} ?> 54 T{sub L}. We split particle pairs at given distances into two types with low and high relative speeds, referred to as continuous and caustic types, respectively, and compute their contributions to the collision kernel. Although amplified by the effect of clustering, the continuous contribution vanishes in the limit of infinitesimal particle distance, where the caustic contribution dominates. The caustic kernel per unit cross section rises rapidly as St increases toward ? 1, reaches a maximum at ?{sub p} ? 2 T{sub L}, and decreases as ?{sub p}{sup -1/2} for ?{sub p} >> T{sub L}.

Pan, Liubin [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Padoan, Paolo, E-mail: lpan@cfa.harvard.edu, E-mail: ppadoan@icc.ub.edu [ICREA and ICC, University of Barcelona, Marti i Franquès 1, E-08028 Barcelona (Spain)

2013-10-10

123

SHORT COMMUNICATION Development of diet-induced fatty liver disease in  

E-print Network

SHORT COMMUNICATION Development of diet-induced fatty liver disease in the aging mouse, USA The age-induced decline in the body's ability to fight disease is exacerbated by obesity and metabolic disease. Using a mouse model of diet-induced obesity, the combined challenge of a high-fat diet

124

Effect of induced electric field on migration of a charged porous particle.  

PubMed

The effect of ambient fluid flow on a charged porous spherical particle suspended in an aqueous medium is analyzed. The porous particle is ion permeable and fluid penetrable. The induced electric field due to the polarization of the particle's electric double layer and counterion condensation leads to a hindrance effect on particle migration by producing an electric force. The influence of this retardation force on the hydrodynamics of the particle is studied through the Nernst-Planck equations, which are coupled with the Stokes-Brinkman equation. The interactions of the double-layer polarization, shielding effect, electroosmosis of unbalanced ions and fluid convection are analyzed. The settling velocity and fluid collection efficiency of the charged aggregate is determined. We have studied the electrokinetics for a wide range of fixed charge density and permeability of the particle with no assumption made on the thickness of the double layer relative to the dimension of the particle. PMID:25374308

Gopmandal, Partha P; Bhattacharyya, S; Barman, Bhanuman

2014-11-01

125

Egr-1 Regulates Autophagy in Cigarette Smoke-Induced Chronic Obstructive Pulmonary Disease  

E-print Network

Egr-1 Regulates Autophagy in Cigarette Smoke-Induced Chronic Obstructive Pulmonary Disease Zhi obstructive pulmonary disease (COPD) is a progressive lung disease characterized by abnormal cellular-Induced Chronic Obstructive Pulmonary Disease. PLoS ONE 3(10): e3316. doi:10.1371/journal.pone.0003316 Editor

126

Possible mechanisms for arsenic-induced proliferative diseases  

SciTech Connect

Possible mechanisms for cardiovascular diseases and cancers which have been observed on chronic exposure to arsenic have been investigated. We tested the hypothesis that nonlethal levels of arsenic are mitogenic, cause oxidative stress, increase nuclear translocation of trans-acting factors, and increase expression of genes involved in proliferation. Cultured porcine vascular (from aorta) endothelial cells were used as a model cell system to study the effects of arsenic on the target cells for cardiovascular diseases. Treatment of postconfluent cell cultures with nonovertly toxic concentrations of arsenite increased DNA synthesis, similar to the mitogenic response observed with hydrogen peroxide. Within 1 hour of adding noncytotoxic concentrations of arsenite, cellular levels of oxidants increased relative to control levels, indicating that arsenite promotes cellular oxidations. Arsenite treatment increased nuclear translocation of NF-{kappa}B, an oxidative stress-responsive transcription factor, in a manner similar to that observed with hydrogen peroxide. Pretreatment of intact cells with the antioxidants N-acetylcysteine and dimethylfumarate prevented the arsenite-induced increases in cellular oxidant formation and NF-KB translocation. Arsenite had little or no effect on binding of NF-KB to its DNA recognition sequence in vitro, indicating that it is unlikely that arsenite directly affects NF-KB. The steady-state mRNA levels of intracellular adhesion molecule and urokinase-like plasminogen activator, genes associated with the active endothelial phenotype in arteriosclerosis and cancer metastasis, were increased by nontoxic concentrations of arsenite. These data suggest that arsenite promotes proliferative diseases like heart disease and cancer by activating oxidant-sensitive endothelial cell signaling and gene expression. It is possible that antioxidant therapy would be useful in preventing arsenic-induced cardiovascular disease and cancer.

Wetterhahn, K.E.; Dudek, E.J.; Shumilla, J.A. [Dartmouth College and Medical School, Hanover, NH (United States)] [and others

1996-12-31

127

Thermal fatigue of particle reinforced metal–matrix composite induced by laser heating and mechanical load  

Microsoft Academic Search

The thermal fatigue of particle reinforced metal–matrix composite induced by repetition-pulsed laser heating and mechanical load was experimentally and numerically studied. It is found that the fatigue damage is initial at the intersection region of laser irradiated brim region and the perpendicular direction of tensile load. The initial damage is induced by void nucleation, growth and subsequent coalescence in the

S. G. Long; Y. C. Zhou

2005-01-01

128

Buckling-induced jamming in channel flow of particle rafts  

NASA Astrophysics Data System (ADS)

We report on observations of the flow of plastic particles floating on the surface of water in a rectangular channel. The system is driven by moving one wall of the channel at a constant velocity. The opposite side of the channel is open, and the particles are pushed into a region free of material. During the flow, video of the particle motions is captured, and the average force on the pushing wall is measured. We have studied particle shapes that are both circular disks and rectangular bars. We find that when the rectangular bars form a layer at the side walls of the channel (whether or not the central region is filled with disks or additional rectangular bars), the system exhibits sudden increases and decreases in the average force on the driving wall. This behavior is consistent with the existence of jamming in the system. We report on the shape and velocity dependence of these force fluctuations, and the evidence that buckling of the rectangular blocks at the wall is responsible for generating the jamming dynamics.

Kuo, Chin-Chang; Dennin, Michael

2013-03-01

129

Role of direct estrogen receptor signaling in wear particle-induced osteolysis  

PubMed Central

Estrogen withdrawal following surgical ovariectomy was recently shown to mitigate particle-induced osteolysis in the murine calvarial model. Currently, we hypothesize that estrogen receptors (ERs) were involved in this paradoxical phenomenon. To test this hypothesis, we first evaluated polyethylene (PE) particle-induced osteolysis in the murine calvarial model, using wild type (WT) C57BL6J female mice, ER? deficient (ER?KO) mice, and WT mice either treated with 17?-estradiol (E2) or with the ER pan-antagonist ICI 182,780. According to micro-CT and histomorphometry, we showed that bone resorption was consistently altered in both ER?KO and ICI 182,780 treated mice as compared to WT and E2 groups. Then, we demonstrated that ER disruption consistently decreased both PE and polymethylmethacrylate (PMMA) particle-induced production of TNF-? by murine macrophages in vitro. Similar results were obtained following ER blockade using ICI 182,780 in RAW 264.7 and WT macrophages. ER disruption and pre treatment with ICI 182,780 resulted in a consistent down-regulation of particle-induced TNF-? mRNA expression relative to WT macrophages or untreated RAW cells. These results indicate that the response to wear particles involves estrogen receptors in female mice, as part of macrophage activation. Estrogen receptors may be considered as a future therapeutic target for particle-induced osteolysis. PMID:23113918

Nich, Christophe; Rao, Allison J.; Valladares, Roberto D.; Li, Chenguang; Christman, Jane E.; Antonios, Joseph K.; Yao, Zhenyu; Zwingenberger, Stefan; Petite, Hervé; Hamadouche, Moussa; Goodman, Stuart B.

2014-01-01

130

The preferential targeting of the diseased microvasculature by disk-like particles  

PubMed Central

Different classes of nanoparticles (NPs) have been developed for controlling and improving the systemic administration of therapeutic and contrast agents. Particle shape has been shown to be crucial in the vascular transport and adhesion of NPs. Here, we use mesoporous silicon non-spherical particles, of disk and rod shapes, ranging in size from 200 nm to 1800 nm. The fabrication process of the mesoporous particles is described in detail, and their transport and adhesion properties under flow are studied using a parallel plate flow chamber. Numerical simulations predict the hydrodynamic forces on the particles and help in interpreting their distinctive behaviors. Under microvascular flow conditions, for disk-like shape, 1000×400 nm particles show maximum adhesion, whereas smaller (600×200 nm) and larger (1800×600 nm) particles adhere less by a factor of about two. Larger rods (1800×400 nm) are observed to adhere at least 3 times more than smaller ones (1500×200 nm). For particles of equal volumes, disks adhere about 2 times more than rods. Maximum adhesion for intermediate sized disks reflects the balance between adhesive interfacial interactions and hydrodynamic dislodging forces. In view of the growing evidence on vascular molecular heterogeneity, the present data suggest that thin disk-like particles could more effectively target the diseased microvasculature as compared to spheres and slender rods. PMID:22579236

Adriani, Giulia; de Tullio, Marco D.; Ferrari, Mauro; Hussain, Fazle; Pascazio, Giuseppe; Liu, Xuewu; Decuzzi, Paolo

2012-01-01

131

FACTORS THAT INFLUENCE THE RELATIVE POTENCY OF DIESEL EXHAUST PARTICLES AS ADJUVANTS IN ALLERGIC AIRWAY DISEASE  

EPA Science Inventory

Description: Studies have shown that diesel exhaust particles (DEP) worsen respiratory diseases including allergic asthma. The adjuvant effects of DEP in the airways have been widely reported; however, the precise determinants and mechanisms of these effects are ill-defined. S...

132

Comparison of the performance of particle filter algorithms applied to tracking of a disease epidemic.  

PubMed

We present general methodology for sequential inference in nonlinear stochastic state-space models to simultaneously estimate dynamic states and fixed parameters. We show that basic particle filters may fail due to degeneracy in fixed parameter estimation and suggest the use of a kernel density approximation to the filtered distribution of the fixed parameters to allow the fixed parameters to regenerate. In addition, we show that "seemingly" uninformative uniform priors on fixed parameters can affect posterior inferences and suggest the use of priors bounded only by the support of the parameter. We show the negative impact of using multinomial resampling and suggest the use of either stratified or residual resampling within the particle filter. As a motivating example, we use a model for tracking and prediction of a disease outbreak via a syndromic surveillance system. Finally, we use this improved particle filtering methodology to relax prior assumptions on model parameters yet still provide reasonable estimates for model parameters and disease states. PMID:25016201

Sheinson, Daniel M; Niemi, Jarad; Meiring, Wendy

2014-09-01

133

Mineralogical and geochemical aspects of mineral-induced disease  

SciTech Connect

Many minerals are known to cause disease following inhalation, including asbestos, silica, zeolites, and clays. The mineralogical properties that determine toxicity are not known, hindering effective risk assessment. Consequently, many minerals that do not pose risks are controlled excessively and many minerals that do pose risk remain uncontrolled. The authors are integrating mineralogy and biology in an interdisciplinary scientific investigation of the mechanisms of mineral-induced disease. The biological endpoints include the formation of ferruginous bodies and chemical signaling (e.g., production of cytokines or active oxygen species) by cells; the mineralogical variables include structure, composition, and surface properties. The authors are also determining what information about the biological reaction is preserved in the mineral surface.

Guthrie, G.; Raymond, R.; Saffiotti, U.; Aust, A. [Los Alamos National Lab., NM (United States); Mossman, B. [Univ. of Vermont, Burlington, VT (United States)

1996-04-01

134

Correlation of picosecond laser-induced latchup and energetic particle-induced latchup in CMOS test structures  

Microsoft Academic Search

We show that the thresholds for picosecond (psec) laser pulse-induced latchup and energetic particle-induced latchup are well correlated over a range of bulk CMOS test structures designed to be susceptible to latchup. The spatial length of the latchup-sensitive node of the test structures covers a range of values that commonly occur in bulk CMOS devices. The accuracy of this correlation

Steven C. MOSS; Stephen D. LaLumondiere; John R. Scarpulla; Kenneth P. MacWilliams; W. R. Crain; Rocky Koga

1995-01-01

135

Familial Alzheimer's disease modelling using induced pluripotent stem cell technology  

PubMed Central

Alzheimer’s disease (AD) is a progressive neurodegenerative disease in which patients exhibit gradual loss of memory that impairs their ability to learn or carry out daily tasks. Diagnosis of AD is difficult, particularly in early stages of the disease, and largely consists of cognitive assessments, with only one in four patients being correctly diagnosed. Development of novel therapeutics for the treatment of AD has proved to be a lengthy, costly and relatively unproductive process with attrition rates of > 90%. As a result, there are no cures for AD and few treatment options available for patients. Therefore, there is a pressing need for drug discovery platforms that can accurately and reproducibly mimic the AD phenotype and be amenable to high content screening applications. Here, we discuss the use of induced pluripotent stem cells (iPSCs), which can be derived from adult cells, as a method of recapitulation of AD phenotype in vitro. We assess their potential use in high content screening assays and the barriers that exist to realising their full potential in predictive efficacy, toxicology and disease modelling. At present, a number of limitations need to be addressed before the use of iPSC technology can be fully realised in AD therapeutic applications. However, whilst the use of AD-derived iPSCs in drug discovery remains a fledgling field, it is one with immense potential that is likely to reach fruition within the next few years. PMID:24772250

Mohamet, Lisa; Miazga, Natalie J; Ward, Christopher M

2014-01-01

136

Epigenetic regulation of hypoxia inducible factor in diseases and therapeutics.  

PubMed

Hypoxia-inducible factors (HIFs) are master regulators of angiogenesis and cellular adaptation in hypoxic microenvironments. Accumulating evidence indicates that HIFs also regulate cell survival, glucose metabolism, microenvironmental remodeling, cancer metastasis, and tumor progression, and thus, HIFs are viewed as therapeutic targets in many diseases. Epigenetic changes are involved in the switching 'on' and 'off' of many genes, and it has been suggested that the DNA hypermethylation of specific gene promoters, histone modifications (acetylation, phosphorylation, and methylation) and small interfering or micro RNAs be regarded epigenetic gene targets for the regulation of disease-associated cellular changes. Furthermore, the hypoxic microenvironment is one of the most important cellular stress stimuli in terms of the regulation of cellular epigenetic status via histone modification. Therefore, drug development and therapeutic approaches to ischemic diseases or cancer for targeting HIFs by modulation of epigenetic status become an attractive area. Here, the authors provide a review of the literature regarding the targeting of HIF, a key modulator of hypoxic-cell response under various disease conditions, by modulating histone or DNA using endogenous small RNAs or exogenous chemicals. PMID:23440580

Nguyen, Minh Phuong; Lee, Sangkyu; Lee, You Mie

2013-03-01

137

Hypoxia Inducible Factor-1 as a Target for Neurodegenerative Diseases  

PubMed Central

Hypoxia inducible factor-1 (HIF-1) is a transcriptional factor responsible for cellular and tissue adaption to low oxygen tension. HIF-1, a heterodimer consisting of a constitutively expressed ? subunit and an oxygen-regulated ? subunit, regulates a series of genes that participate in angiogenesis, iron metabolism, glucose metabolism, and cell proliferation/survival. The activity of HIF-1 is controlled by post-translational modifications on different amino acid residues of its subunits, mainly the alpha subunit. Besides in ischemic stroke (see review [1]), emerging evidence has revealed that HIF-1 activity and expression of its down-stream genes, such as vascular endothelial growth factor and erythropoietin, are altered in a range of neurodegenerative diseases. At the same time, experimental and clinical evidence has demonstrated that regulating HIF-1 might ameliorate the cellular and tissue damage in the neurodegenerative diseases. These new findings suggest HIF-1 as a potential medicinal target for the neurodegenerative diseases. This review focuses on HIF-1? protein modifications and HIF-1’s potential neuroprotective roles in Alzheimer’s (AD), Parkinson’s (PD), Huntington’s diseases (HD), and amyotrophic lateral sclerosis (ALS). PMID:21861815

Zhang, Ziyan; Yan, Jingqi; Chang, Yanzhong; Yan, Shirley ShiDu; Shi, Honglian

2011-01-01

138

Neonatal jaundice, animal-induced injuries and disease, and immunizations.  

PubMed

The past years' literature on topics of interest to the general practitioner in the areas of neonatal jaundice, animal-induced injury and disease, and immunizations is reviewed. Highlighted are current practice implications of recent publications. As always, the pursuit of excellence in clinical care involves balancing new information with experienced practice. Public health policy, child advocacy, and managed care demands additionally influence the current practice of pediatrics and modify our behavior as pediatricians. However, it is at the bedside that we must strive to provide the most beneficial and compassionate care. PMID:9300206

Gerson, W T

1997-08-01

139

Nonlinear mechanisms for drift wave saturation and induced particle transport  

SciTech Connect

A detailed theoretical study of the nonlinear dynamics of gyrokinetic particle simulations of electrostatic collisionless and weakly collisional drift waves is presented. In previous studies it was shown that, in the nonlinearly saturated phase of the evolution, the saturation levels and especially the particle fluxes have an unexpected dependence on collisionality. In this paper, the explanations for these collisionality dependences are found to be as follows: The saturation level is determined by a balance between the electron and ion fluxes. The ion flux is small for levels of the potential below an E {times} B-trapping threshold and increases sharply once this threshold is crossed. Due to the presence of resonant electrons, the electron flux has a much smoother dependence on the potential. In the 2-1/2-dimensional ( pseudo-3D'') geometry, the electrons are accelerated away from the resonance as they diffuse spatially, resulting in an inhibition of their diffusion. Collisions and three-dimensional effects can repopulate the resonance thereby increasing the value of the particle flux. 30 refs., 32 figs., 2 tabs.

Dimits, A.M. (Maryland Univ., College Park, MD (USA). Lab. for Plasma Research); Lee, W.W. (Princeton Univ., NJ (USA). Plasma Physics Lab.)

1989-12-01

140

Animal models of beryllium-induced lung disease.  

PubMed Central

The inhalation Toxicology Research Institute (ITRI) is conducting research to improve the understanding of chronic beryllium disease (CBD) and beryllium-induced lung cancer. Initial animal studies examined beagle dogs that inhaled BeO calcined at either 500 or 1000 degrees C. At similar lung burdens, the 500 degrees C BeO induced more severe and extensive granulomatous pneumonia, lymphocytic infiltration into the lung, and positive Be-specific lymphocyte proliferative responses in vitro than the 1000 degrees C BeO. However, the progressive nature of human CBD was not duplicated. More recently, Strains A/J and C3H/Hej mice were exposed to Be metal by inhalation. This produced a marked granulomatous pneumonia, diffuse infiltrates, and multifocal aggregates of interstitial lymphocytes with a pronounced T helper component and pulmonary in situ lymphocyte proliferation. With respect to lung cancer, at a mean lung burden as low as 17 micrograms Be/g lung, inhaled Be metal induced benign and/or malignant lung tumors in over 50% of male and female F344 rats surviving > or = 1 year on study. Substantial tumor multiplicity was found, but K-ras and p53 gene mutations were virtually absent. In mice, however, a lung burden of approximately 60 micrograms (-300 micrograms Be/g lung) caused only a slight increase in crude lung tumor incidence and multiplicity over controls in strain A/J mice and no elevated incidence in strain C3H mice. Taken together, this research program constitutes a coordinated effort to understand beryllium-induced lung disease in experimental animal models. PMID:8933044

Finch, G L; Hoover, M D; Hahn, F F; Nikula, K J; Belinsky, S A; Haley, P J; Griffith, W C

1996-01-01

141

Animal models of beryllium-induced lung disease  

SciTech Connect

The Inhalation Toxicology Research Institute (ITRI) is conducting research to improve the understanding of chronic beryllium disease (CBD) and beryllium-induced lung cancer. Initial animal studies examined beagle dogs that inhaled BeO calcined at either 500 or 1000{degrees}C. At similar lung burdens, the 500{degrees}C BeO induced more severe and extensive granulomatous pneumonia, lymphocytic infiltration into the lung, and positive Be-specific lymphocyte proliferative responses in vitro than the 1000{degrees}C BeO. However, the progressive nature of human CBD was not duplicated. More recently, Strains A/J and C3H/HeJ mice were exposed to Be metal by inhalation. This produced a marked granulomatous pneumonia, diffuse infiltrates, and multifocal aggregates of interstitial lymphocytes with a pronounced T helper component and pulmonary in situ lymphocyte proliferation. With respect to lung cancer, at a mean lung burden as low as 17 pg Be/g lung, inhaled Be metal induced benign and/or malignant lung tumors in over 50% of male and female F344 rats surviving {ge}1 year on study. Substantial tumor multiplicity was found, but K-ras and p53 gene mutations were virtually absent. In mice, however, a lung burden of approximately 60 {mu}g ({approximately}300 {mu}g Be/g lung) caused only a slight increase in crude lung tumor incidence and multiplicity over controls in strain A/J mice and no elevated incidence in strain C3H mice. Taken together, this research program constitutes a coordinated effort to understand beryllium-induced lung disease in experimental animal models. 47 refs., 1 fig., 3 tabs.

Finch, G.L.; Hoover, M.D.; Hahn, F.F. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States)] [and others

1996-10-01

142

Wear particles generated from studded tires and pavement induces inflammatory reactions in mouse macrophage cells.  

PubMed

Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. These health risks are of increasing concern in society, and to protect public health, a clarification of the toxic properties of particles from different sources is of importance. Lately, wear particles generated from traffic have been recognized as a major contributing source to the overall particle load, especially in the Nordic countries where studded tires are used. The aim of this study was to further investigate and compare the ability to induce inflammatory mediators of different traffic-related wear particles collected from an urban street, a subway station, and studded tire-pavement wear. Inflammatory effects were measured as induction of nitric oxide (NO), IL-6, TNF-alpha, arachidonic acid (AA), and lipid peroxidation after exposure of the murine macrophage like cell line RAW 264.7. In addition, the redox potential of the particles was measured in a cell-free system. The results show that all particles tested induce IL-6, TNF-alpha, and NO, and those from the urban street were the most potent ones. In contrast, particles collected from a subway station were most potent to induce lipid peroxidation, AA release, and formation of ROS. Particles from studded tire-pavement wear, generated using a road simulator, were able to induce inflammatory cytokines, NO, lipid peroxidation, and ROS formation. Interestingly, particles generated from pavement containing granite as the main stone material were more potent than those generated from pavement containing quartzite as the main stone material. PMID:17516662

Lindbom, John; Gustafsson, Mats; Blomqvist, Göran; Dahl, Andreas; Gudmundsson, Anders; Swietlicki, Erik; Ljungman, Anders G

2007-06-01

143

Wave induced transport and mixing of buoyant particles  

NASA Astrophysics Data System (ADS)

The modeling of wave-current and wave-turbulence interactions have received much attention during recent years. Both the breaking of surface waves and the inclusion of the Stokes shear production have been shown to increase the upper ocean turbulence. Furthermore the Coriolis force acting on the Stokes drift redistributes the momentum in the upper ocean, leading to a deflection of the currents. An important application affected by these processes that still needs to be studied is the mixing and drift of particles. Using an ocean column model, modified to take surface wave effects into account, we investigate how the increased mixing by wave breaking and Stokes shear production as well as the stronger veering by the Coriolis-Stokes force effects the drift of suspended particles. Here the suspended particles are buoyant tracers that can represent oil droplets or plankton, for example fish eggs and larvae. The energy and momentum fluxes as well as the Stokes drift depend on the directional wave spectrum that can be obtained from a wave model or from observations. Comparing with classical Ekman theory some physical effects on the system are studied, and as a realistic test case we use the model to study the oil drift after an offshore oil spill that took place outside the western coast of Norway in 2007. During this accident the average net drift of oil was observed to be approximately 0.1% of the wind speed at an angle of about 90-120 degrees to the right, far slower and more deflected away from the wind direction than predicted by both numerical and empirical models. With wind and wave forcing from ECMWF reanalysis data, it is shown that the wave effects are important for the resultant drift in this case, and has the potential to improve drift forecasting.

Drivdal, Magnus; Broström, Göran; Christensen, Kai H.

2014-05-01

144

Corporation-induced diseases, upstream epidemiologic surveillance, and urban health.  

PubMed

Corporation-induced diseases are defined as diseases of consumers, workers, or community residents who have been exposed to disease agents contained in corporate products. To study the epidemiology and to guide expanded surveillance of these diseases, a new analytical framework is proposed. This framework is based on the agent-host-environment model and the upstream multilevel epidemiologic approach and posits an epidemiologic cascade starting with government-sanctioned corporate profit making and ending in a social cost, i.e., harm to population health. Each of the framework's levels addresses a specific level of analysis, including government, corporations, corporate conduits, the environment of the host, and the host. The explained variable at one level is also the explanatory variable at the next lower level. In this way, a causal chain can be followed along the epidemiologic cascade from the site of societal power down to the host. The framework thus describes the pathways by which corporate decisions filter down to disease production in the host and identifies opportunities for epidemiologic surveillance. Since the environment of city dwellers is strongly shaped by corporations that are far upstream and several levels away, the framework has relevance for the study of urban health. Corporations that influence the health of urban populations include developers and financial corporations that determine growth or decay of urban neighborhoods, as well as companies that use strategies based on neighborhood characteristics to sell products that harm consumer health. Epidemiological inquiry and surveillance are necessary at all levels to provide the knowledge needed for action to protect the health of the population. To achieve optimal inquiry and surveillance at the uppermost levels, epidemiologists will have to work with political scientists and other social scientists and to utilize novel sources of information. PMID:18437580

Jahiel, René I

2008-07-01

145

Corporation-induced Diseases, Upstream Epidemiologic Surveillance, and Urban Health  

PubMed Central

Corporation-induced diseases are defined as diseases of consumers, workers, or community residents who have been exposed to disease agents contained in corporate products. To study the epidemiology and to guide expanded surveillance of these diseases, a new analytical framework is proposed. This framework is based on the agent–host–environment model and the upstream multilevel epidemiologic approach and posits an epidemiologic cascade starting with government-sanctioned corporate profit making and ending in a social cost, i.e., harm to population health. Each of the framework’s levels addresses a specific level of analysis, including government, corporations, corporate conduits, the environment of the host, and the host. The explained variable at one level is also the explanatory variable at the next lower level. In this way, a causal chain can be followed along the epidemiologic cascade from the site of societal power down to the host. The framework thus describes the pathways by which corporate decisions filter down to disease production in the host and identifies opportunities for epidemiologic surveillance. Since the environment of city dwellers is strongly shaped by corporations that are far upstream and several levels away, the framework has relevance for the study of urban health. Corporations that influence the health of urban populations include developers and financial corporations that determine growth or decay of urban neighborhoods, as well as companies that use strategies based on neighborhood characteristics to sell products that harm consumer health. Epidemiological inquiry and surveillance are necessary at all levels to provide the knowledge needed for action to protect the health of the population. To achieve optimal inquiry and surveillance at the uppermost levels, epidemiologists will have to work with political scientists and other social scientists and to utilize novel sources of information. PMID:18437580

2008-01-01

146

MHD-Induced Alpha Particle Loss in TFTR S.J. Zweben, D.S. Darrow, E.D. Fredrickson,  

E-print Network

1 MHD-Induced Alpha Particle Loss in TFTR S.J. Zweben, D.S. Darrow, E.D. Fredrickson, G. Taylor, S MHD-induced increases in alpha particle loss to the wall were observed for both coherent modes of the coherent MHD-induced alpha loss as seen by these detectors was normally comparable to the MHD

147

Transition induced by fixed and freely convecting spherical particles in laminar boundary layers  

NASA Astrophysics Data System (ADS)

An experimental and analytical study of aspects of transition induced by disturbances from spherical particles in laminar boundary layers is discussed. The generation of turbulent wedges by fixed spherical particles in a laminar boundary layer on or near the surface of a flat plate is considered experimentally using flow visualization with fluorescent dye and laser Doppler velocimetry. Turbulent spots generated by freely convecting spherical particles that are released in the freestream to fall into a flat plate laminar boundary layer and impact the plate are also discussed. A combination of dye flow visualization and a video based particle tracking technique was used to study the convecting particle problem. Although the Reynolds number at the critical condition for turbulent wedge generation by fixed particles and turbulent spot generation by convecting particles are similar, transition in these two situations appears to be fundamentally different. The development of a turbulent wedge near the critical condition is a relatively gradual process. In contrast, turbulent spots form relatively quickly after the convecting particles enter the boundary layer and impact the plate. Turbulent wedge formation downstream of a fixed particle results from the destabilization of the near wall flow by the vortical structures shed into particle wake. This shedding process is dominated by periodically shed loop shaped hairpin vortices. Observation of subharmonic oscillations at 1/2 and 1/4 of this shedding frequency suggest that a chaotic route to turbulence by a series of period doubling bifurcations is possible.

Petrie, H. L.; Morris, P. J.; Bajwa, A. R.; Vincent, D. C.

1993-08-01

148

In vivo Expression of Inducible Nitric Oxide Synthase in Experimentally Induced Neurologic Diseases  

NASA Astrophysics Data System (ADS)

The purpose of this study was to investigate the induction of inducible nitric oxide synthase (iNOS) mRNA in the brain tissue of rats and mice under the following experimental conditions: in rats infected with borna disease virus and rabies virus, in mice infected with herpes simplex virus, and in rats after the induction of experimental allergic encephalitis. The results showed that iNOS mRNA, normally nondetectable in the brain, was present in animals after viral infection or after induction of experimental allergic encephalitis. The induction of iNOS mRNA coincided with the severity of clinical signs and in some cases with the presence of inflammatory cells in the brain. The results indicate that nitric oxide produced by cells induced by iNOS may be the toxic factor accounting for cell damage and this may open the door to approaches to the study of the pathogenesis of neurological diseases.

Koprowski, Hilary; Zheng, Yong Mu; Heber-Katz, Ellen; Fraser, Nigel; Rorke, Lucy; Fu, Zhen Fang; Hanlon, Cathleen; Dietzschold, Bernhard

1993-04-01

149

Self-induced polar order of active Brownian particles in a harmonic trap  

E-print Network

Hydrodynamically interacting active particles in an external harmonic potential form a self-assembled fluid pump at large enough P\\'eclet numbers. Here, we give a quantitative criterion for the formation of the pump and show that particle orientations align in the self-induced flow field in surprising analogy to ferromagnetic order where the active P\\'eclet number plays the role of inverse temperature. The particle orientations follow a Boltzmann distribution $\\Phi(\\mathbf{p}) \\sim \\exp(A p_z)$ where the ordering mean field $A$ scales with active P\\'eclet number and polar order parameter. The mean flow field in which the particles' swimming directions align corresponds to a regularized stokeslet with strength proportional to swimming speed. Analytic mean-field results are compared with results from Brownian dynamics simulations with hydrodynamic interactions included and are found to capture the self-induced alignment very well.

Marc Hennes; Katrin Wolff; Holger Stark

2014-02-06

150

Desorption of carbon dioxide from small potassium niobate particles induced by the particles’ ferroelectric transition  

Microsoft Academic Search

The aim of this work is to understand surface properties of ferroelectric crystals related to gas adsorption. Various ferroelectric crystals involved in these studies readily adsorb carbon dioxide, thus our studies were centered on adsorption studies of this molecule. It has been claimed that a dipole moment is induced on carbon dioxide molecules that are near an oxide surface. Our

E. Ramos-Moore; J. A. Baier-Saip; A. L. Cabrera

2006-01-01

151

Desorption of carbon dioxide from small potassium niobate particles induced by the particles' ferroelectric transition  

Microsoft Academic Search

The aim of this work is to understand surface properties of ferroelectric crystals related to gas adsorption. Various ferroelectric crystals involved in these studies readily adsorb carbon dioxide, thus our studies were centered on adsorption studies of this molecule. It has been claimed that a dipole moment is induced on carbon dioxide molecules that are near an oxide surface. Our

E. Ramos-Moore; J. A. Baier-Saip; A. L. Cabrera

2006-01-01

152

Particle-induced amorphization of complex ceramics. Final report  

SciTech Connect

The crystalline-to-amorphous (c-a) phase transition is of fundamental importance. Particle irradiations provide an important, highly controlled means of investigating this phase transformation and the structure of the amorphous state. The interaction of heavy-particles with ceramics is complex because these materials have a wide range of structure types, complex compositions, and because chemical bonding is variable. Radiation damage and annealing can produce diverse results, but most commonly, single crystals become aperiodic or break down into a polycrystalline aggregate. The authors continued the studies of the transition from the periodic-to-aperiodic state in natural materials that have been damaged by {alpha}-recoil nuclei in the uranium and thorium decay series and in synthetic, analogous structures. The transition from the periodic to aperiodic state was followed by detailed x-ray diffraction analysis, in-situ irradiation/transmission electron microscopy, high resolution transmission electron microscopy, extended x-ray absorption fine structure spectroscopy/x-ray absorption near edge spectroscopy and other spectroscopic techniques. These studies were completed in conjunction with bulk irradiations that can be completed at Los Alamos National Laboratory or Sandia National Laboratories. Principal questions addressed in this research program included: (1) What is the process at the atomic level by which a ceramic material is transformed into a disordered or aperiodic state? (2) What are the controlling effects of structural topology, bond-type, dose rate, and irradiation temperature on the final state of the irradiated material? (3) What is the structure of the damaged material? (4) What are the mechanisms and kinetics for the annealing of interstitial and aggregate defects in these irradiated ceramic materials? (5) What general criteria may be applied to the prediction of amorphization in complex ceramics?

Ewing, R.C.; Wang, L.M.

1998-08-01

153

Optical fiber measurements of particle velocity using laser-induced phosphorescence  

SciTech Connect

An optical fiber anemometer that uses laser-induced phosphorescence to measure particle time of flight in dense gas-solid suspensions is described. The anemometer is tested using a spinning disk coated with a phosphor having a persistent afterglow. The diagnostic technique is illustrated by measuring the velocity of free-falling particles coated with the same phosphor. Monte Carlo simulations are employed to determine the optical characteristics of the probe, including its measurement volume.

Louge, M.Y. (Cornell University, Ithaca, New York 14853-7501 (USA)); Iyer, S.A.; Giannelis, E.P. (Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853-7501 (USA)); Lischer, D.J.; Chang, H. (Sibley School of Mechanical Aerospace Engineering, Cornell University, Ithaca, New York 14853-7501 (USA))

1991-05-20

154

Detection of Aerosol Particles by Time-Resolved Laser Induced Breakdown Spectroscopy and its Emission Properties  

NASA Astrophysics Data System (ADS)

Development of in-situ and real-time detection techniques for is strongly expected for the human health and public welfare. Particles of SPM size in the air can be exploded by a focused high power laser pulse, and the concentration and composition of the particles are observed by measuring the intensity and the spectra of plasma emission of the particles exploded. Laser induced breakdown spectroscopy is a conventional detection method based on this particle explosion. In the present work, the time-resolved technique was combined with the laser induced breakdown spectroscopic method, in order to improve the signal/noise ratio and efficiency. In this work, firstly, the time-resolved laser induced breakdown spectroscopy system was established in the laboratory and the CaCO3 particles flowing in the air was detected by measuring the Ca II emission at 396nm. Linear calibration curve was obtained between 1x10-4g/m3-5x10-4g/m3 for CaCO3 particles. Secondly, we studied whether TiO2 particles in the presence and in the absence of Eu on their surface could be distinguished by the time-resolved laser induced breakdown spectroscopy. It was found that the dependence of peak intensity of Ti I emission at 453 nm on the laser power consisted of two regions for low Eu loading and of one for high Eu loading. This difference is considered to be caused by different mechanisms in initial electron density formation, suggesting that TiO2 particles in the presence and in the absence of Eu on their surface was distinguished.

Nagasaki, S.; Tanaka, Y.; Kado, S.; Tanaka, S.

2001-12-01

155

Measurement of sputtered Mg particles in a plasma display panel discharge using laser induced fluorescence technique  

Microsoft Academic Search

Spatiotemporal distribution of Mg particles emitted from an MgO surface during an alternating current (ac) plasma display panel (PDP) discharge was directly measured using the laser induced fluorescence (LIF) technique. The results showed the existence of floating Mg particles intermittently emitted during short-lived PDP discharges. A spatial profile at 2 mm above the MgO surface had a peak at around

Youl-Moon Sung; Masahisa Otsubo; Chikahisa Honda

2006-01-01

156

Use of a Soluble Epoxide Hydrolase Inhibitor in Smoke-Induced Chronic Obstructive Pulmonary Disease  

E-print Network

Use of a Soluble Epoxide Hydrolase Inhibitor in Smoke-Induced Chronic Obstructive Pulmonary Disease Tobacco smoke-induced chronic obstructive pulmonary disease (COPD) is a prolonged inflammatory condition; anti-inflammatory agents; airway obstruction Chronic obstructive pulmonary disease (COPD) is a major

Hammock, Bruce D.

157

Infectious particles, stress, and induced prion amyloids: a unifying perspective.  

PubMed

Transmissible encephalopathies (TSEs) are believed by many to arise by spontaneous conversion of host prion protein (PrP) into an infectious amyloid (PrP-res, PrP (Sc) ) without nucleic acid. Many TSE agents reside in the environment, with infection controlled by public health measures. These include the disappearance of kuru with the cessation of ritual cannibalism, the dramatic reduction of epidemic bovine encephalopathy (BSE) by removal of contaminated feed, and the lack of endemic scrapie in geographically isolated Australian sheep with susceptible PrP genotypes. While prion protein modeling has engendered an intense focus on common types of protein misfolding and amyloid formation in diverse organisms and diseases, the biological characteristics of infectious TSE agents, and their recognition by the host as foreign entities, raises several fundamental new directions for fruitful investigation such as: (1) unrecognized microbial agents in the environmental metagenome that may cause latent neurodegenerative disease, (2) the evolutionary social and protective functions of different amyloid proteins in diverse organisms from bacteria to mammals, and (3) amyloid formation as a beneficial innate immune response to stress (infectious and non-infectious). This innate process however, once initiated, can become unstoppable in accelerated neuronal aging. PMID:23633671

Manuelidis, Laura

2013-07-01

158

Non-targeted effects induced by high LET charged particles  

NASA Astrophysics Data System (ADS)

Radiation-induced non-targeted response represents a paradigm shift in our understanding of the radiobiological effects of ionizing radiation in that extranuclear and extracellular effects may also contribute to the final biological consequences of exposure to low doses of radiation. Using the gpt delta transgenic mouse model, there is evidence that irradiation of a small area (1 cm by 1 cm) of the lower abdominal area of animals with a 5 Gy dose of X-rays induced cyclooxygenase-2 as well as deletion mutations in the out-of-field lung tissues of the animals. The mutation correlated with an increase in prostaglandin levels in the bystander lung tissues and with an increase in the level of 8-hydroxydeoxyguanosine (8-OHdG), an oxidative DNA damage marker. An increase in COX-2 level was also detected in the out-of-field lung tissues of animals similarly exposed to high LET argon and carbon ions accelerated at the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences in Japan. These results provide the first evidence that the COX-2 -related pathway, which is essential in mediating cellular inflammatory response, is the critical signaling link for the non-targeted, bystander phenomenon. A better understanding of the cellular and molecular mechanisms of the non-targeted, out of field phenomenon together with evidence of their occurrence in vivo will allow us to formulate a more accurate assessment of radiation risk.

Hei, Tom K.; Chai, Yunfei; Hamada, Nobuyuki; Kakinuma, Shizuko; Uchihori, Yukio

159

Preparation of polystyrene latex particles by ?-rays-induced emulsifier-free emulsion polymerization  

NASA Astrophysics Data System (ADS)

Monodisperse polystyrene latex particles were prepared by 60Co- ?-ray radiation-induced emulsifier-free emulsion polymerization with the use of surfactant monomer at room temperature. The surfactant monomer 10(9)-hydroxyl-9(10)-allyl ether octadecanoic acid (HAEOA) was synthesized and characterized by FT-IR and 1H-NMR spectra. TEM was used to characterize the polystyrene latex particles. HAEOA acted as not only a comonomer but also a stabilizer to copolymerize with styrene and stabilize the polystyrene latex particles. Kinetics analysis shows that there is no constant rate stage which seems to indicate a droplet nucleation mechanism.

Wang, Xinbo; Zhang, Zhicheng

2006-09-01

160

Turbulence-Induced Relative Velocity of Dust Particles II: The Bidisperse Case  

E-print Network

We investigate the relative velocity of inertial particles induced by turbulent motions, extending our earlier work on equal-size particles to the bidisperse case for different particles of arbitrary sizes. The model of Pan & Padoan (PP10) shows that the relative velocity between different particles has two contributions, named the generalized shear and acceleration terms, respectively. The generalized shear term represents the particles' memory of the spatial flow velocity difference across the particle distance at given times in the past, while the acceleration term is associated with the temporal flow velocity difference on individual particle trajectories. The latter vanishes for equal-size particles. Using a simulation, we compute the root-mean-square (rms) relative velocity, ^1/2, as a function of the particle friction times, tau_p1 and tau_p2, and show that the prediction of the PP10 model is in satisfactory agreement with the data, confirming the validity of its physical picture. For a given tau_p...

Pan, Liubin; Scalo, John

2014-01-01

161

Sheath-induced distortions in particle distributions near enhanced polar outflow probe particle sensors  

NASA Astrophysics Data System (ADS)

We discuss sheath and kinetic effects on ion and electron distribution functions at the aperture of enhanced Polar Outflow Probe particle sensors. For this purpose, the interaction between the CASSIOPE spacecraft and space environment is simulated fully kinetically using the electrostatic Particle In Cell code PTetra. The simulations account for the geometry of the main features of the spacecraft body, the booms, and the sensors. In addition to the background plasma, the model also accounts for Earth magnetic field. The plasma parameters assumed in the simulations are obtained from the latest version of the International Reference Ionosphere (IRI) model and the value of magnetic field is obtained from the International Geophysical Reference Field model. Our analysis shows significant distortions in the ion distribution function in the plane of the sensor aperture, as well as in the direction along the boom holding the sensor. We argue that significant distortions and asymmetries should also occur at the aperture of the suprathermal electron imager when suprathermal electrons are detected, with energies of 5 eV or more.

Hussain, S.; Marchand, R.

2014-07-01

162

Rapid appearance of transient secondary adrenocortical insufficiency after alpha-particle radiation therapy for Cushing's disease  

Microsoft Academic Search

A 17-year-old woman received 12,000 rads of alpha-particle radiation for the treatment of Cushing's disease. One day after the completion of therapy, the patient developed nausea, vomiting, headache, and postural hypotension. Laboratory evaluation demonstrated a marked fall of the previously elevated urinary 17-hydroxycorticosteroids (17-OHCS) and undetectable plasma cortisols. The urinary 17-OHCS transiently returned to supranormal levels but over a 2¹\\/â-week

D. M. Cook; R. M. Jordan; J. W. Kendall; J. A. Linfoot

1976-01-01

163

Laser-induced incandescence of soot particles in the flue gas evolved by coal pyrolysis  

NASA Astrophysics Data System (ADS)

For the measurement of solid fine particles in pyrolysis systems, laser-induced incandescence (LII) has been proved to be a powerful technique for obtaining volume fraction and primary particles sizes of soot particles. In this paper, a Monte Carlo simulation is developed to analyze the influence on the detected LII flux of soot particles with the presence of coal pyrolysis products between a detector and a laser-induced incandescence control zone. The analysis corresponds to a first approach of the measurement technique, when two distinct aerosols are present around the LII control volume. The evolved flue gas of coal pyrolysis is assumed to be composed of N2, CO2, CO, CH4 and fine carbon particles (soot and fly-ash particles), exhibiting spectrally dependent absorption, and anisotropically light scattering. The developed Monte Carlo simulation is applied to analyze successive absorption and scattering, especially multiple scattering events in any sequence during the propagation of LII emission. The results show that the influence of the flue gas on the detected fluxes is not uniform along the whole wavelengths spectrum. The measurement bias of LII technique for soot particles is presented when modifying coal pyrolysis products composition.

Chen, Linghong; Garo, Annie; Cen, Kefa; Grehan, Gerard

2007-06-01

164

PIV Measurements of Particle and Fluid Motion Induced by AC Electric Fields  

NASA Astrophysics Data System (ADS)

The techniques to induce particle and fluid motion inside microsystems using ac electric fields have important applications in sensing and manipulating bioparticles. Micron-Resolution Particle Image Velocimetry (m-PIV) is a powerful tool to measure the spatially resolved motion with resolution approaching 1mm. In the presence of nonuniform ac electric fields, the particles experience dielectrophoretic (DEP) forces due to polarization and drag forces due to viscous interaction with the suspending medium, and the fluid is put into motion by electrothermal effect, ac electroosmosis, or both. Typically, m-PIV measures the fluid velocity by tracking the motion of fluorescent particles with an assumption that the particles faithfully follow the fluid flow. But in our experiments the particle velocity is different from the underlining fluid velocity due to the DEP forces on the particles induced by the applied electric fields. In order to determine fluid velocity under nonuniform electric fields, we used a technique called Two-color m-PIV (Meinhart et al., 2003). In an effort to find the mechanisms behind the fluid motion, we measured fluid velocity at several regions within a microchannel over a range of applied voltages. The results indicate that the fluid motion is caused by combination of electrothermal effect and ac electroosmosis, and that electrothermal effect is more important at the bulk fluid.

Wang, Dazhi; Meinhart, Carl; Sigurdson, Marin

2003-11-01

165

Drug-induced autoimmune liver disease: A diagnostic dilemma of an increasingly reported disease  

PubMed Central

The aetiology of autoimmune hepatitis (AIH) is uncertain but the disease can be triggered in susceptible patients by external factors such as viruses or drugs. AIH usually develops in individuals with a genetic background mainly consisting of some risk alleles of the major histocompatibility complex (HLA). Many drugs have been linked to AIH phenotypes, which sometimes persist after drug discontinuation, suggesting that they awaken latent autoimmunity. At least three clinical scenarios have been proposed that refers to drug- induced autoimmune liver disease (DIAILD): AIH with drug-induced liver injury (DILI); drug induced-AIH (DI-AIH); and immune mediated DILI (IM-DILI). In addition, there are instances showing mixed features of DI-AIH and IM-DILI, as well as DILI cases with positive autoantibodies. Histologically distinguishing DILI from AIH remains a challenge. Even more challenging is the differentiation of AIH from DI-AIH mainly relying in histological features; however, a detailed standardised histologic evaluation of large cohorts of AIH and DI-AIH patients would probably render more subtle features that could be of help in the differential diagnosis between both entities. Growing information on the relationship of drugs and AIH is being available, being drugs like statins and biologic agents more frequently involved in cases of DIAILD. In addition, there is some evidence on the fact that patients diagnosed with DIAILD may have had a previous episode of hepatotoxicity. Further collaborative studies in DIAILD will strengthen the knowledge and understanding of this intriguing and complex disorder which might represent different phenotypes across the spectrum of disease PMID:24799984

Castiella, Agustin; Zapata, Eva; Lucena, M Isabel; Andrade, Raul J

2014-01-01

166

Gross Cystic Disease Fluid Protein-15/Prolactin-Inducible Protein as a Biomarker for Keratoconus Disease  

PubMed Central

Keratoconus (KC) is a bilateral degenerative disease of the cornea characterized by corneal bulging, stromal thinning, and scarring. The etiology of the disease is unknown. In this study, we identified a new biomarker for KC that is present in vivo and in vitro. In vivo, tear samples were collected from age-matched controls with no eye disease (n?=?36) and KC diagnosed subjects (n?=?17). Samples were processed for proteomics using LC-MS/MS. In vitro, cells were isolated from controls (Human Corneal Fibroblasts-HCF) and KC subjects (Human Keratoconus Cells-HKC) and stimulated with a Vitamin C (VitC) derivative for 4 weeks, and with one of the three transforming growth factor-beta (TGF-?) isoforms. Samples were analyzed using real-time PCR and Western Blots. By using proteomics analysis, the Gross cystic disease fluid protein-15 (GCDFP-15) or prolactin-inducible protein (PIP) was found to be the best independent biomarker able to discriminate between KC and controls. The intensity of GCDFP-15/PIP was significantly higher in healthy subjects compared to KC-diagnosed. Similar findings were seen in vitro, using a 3D culture model. All three TGF-? isoforms significantly down-regulated the expression of GCDFP-15/PIP. Zinc-alpha-2-glycoprotein (AZGP1), a protein that binds to PIP, was identified by proteomics and cell culture to be highly regulated. In this study by different complementary techniques we confirmed the potential role of GCDFP-15/PIP as a novel biomarker for KC disease. It is likely that exploring the GCDFP-15/PIP-AZGP1 interactions will help better understand the mechanism of KC disease. PMID:25405607

Priyadarsini, Shrestha; Hjortdal, Jesper; Sarker-Nag, Akhee; Sejersen, Henrik; Asara, John M.; Karamichos, Dimitrios

2014-01-01

167

Differential Requirements for T Cells in Viruslike Particle and Rotavirus-Induced Protective Immunity  

Microsoft Academic Search

Correlates of protection from rotavirus infection are controversial. We compared the roles of B and T lymphocytes in protective immunity induced either by intranasally administered nonreplicating viruslike particles or inactivated virus or by orally administered murine rotavirus. We found that protection induced by nonreplicating vaccines requires CD4 T cells and CD40\\/CD40L. In contrast, T cells were not required for short-term

Sarah E. Blutt; Kelly L. Warfield; Mary K. Estes; Margaret E. Conner

2008-01-01

168

Determination of low-z elements in atmospheric aerosols by charged-particle-induced nuclear reactions  

Microsoft Academic Search

Nuclear reactions induced by charged particles are used to determine total carbon, nitrogen, and oxygen in atmospheric aerosols. These simple activation methods are quite sensitive, nondestructive, and require only a short amount of beam time (one minute in most cases) for each sample analysis. The method for determination of nitrogen in aerosols uses a proton beam to induce the ¹⁴N(p,..cap

Clemenson

1979-01-01

169

ULTRAFINE CARBON PARTICLES INDUCE INTERLEUKIN-8 GENE TRANSCRIPTION AND P38 MAPK ACTIVATION IN NORMAL BRONCHIAL EPITHELIAL CELLS  

EPA Science Inventory

Epidemiological studies suggest that ultrafine particles contribute to particulate matter-induced adverse health effects. Interleukin (IL)-8 is an important proinflammatory cytokine in the human lung that is induced in respiratory cells exposed to a variety of environmental insul...

170

Local effect of IL-4 delivery on polyethylene particle induced osteolysis in the murine calvarium  

PubMed Central

Wear particles generated with use of total joint replacements incite a chronic macrophage-mediated inflammatory reaction, which leads to implant failure. Macrophage activation may be polarized into two states, with an M1 proinflammatory state dominating an alternatively activated M2 anti-inflammatory state. We hypothesized that IL-4, an activator of M2 macrophages, could modulate polyethylene (PE) particle-induced osteolysis in an experimental murine model. Four animal groups included (a) calvarial saline injection with harvest at 14 days (b) single calvarial injection of PE particles subcutaneously (SC) without IL-4 (c) PE particles placed as in (b), then IL-4 given SC for 14 consecutive days and (d) PE particles as in (b) then IL-4 beginning 7 days after particle injection for 7 days. The calvarial bone volume to total tissue volume was measured using microCT and histomorphometry. Calvaria were cultured for 24 h to assess release of RANKL, OPG, TNF-?, and IL-1ra and isolation and identification of M1 and M2 specific proteins. MicroCT and histomorphometric analysis showed that bone loss was significantly decreased following IL-4 administration to PE treated calvaria for both 7 and 14 days. Western blot analysis showed an increased M1/M2 ratio in the PE treated calvaria, which decreased with addition of IL-4. Cytokine analysis showed that the RANKL/OPG ratio and TNF-?/IL-1ra ratio decreased in PE-treated calvaria following IL-4 addition for 14 days. IL-4 delivery mitigated PE particle-induced osteolysis through macrophage polarization. Modulation of macrophage polarization is a potential treatment strategy for wear particle induced periprosthetic osteolysis. PMID:23225668

Rao, Allison J.; Nich, Christophe; Dhulipala, Lakshmi S.; Gibon, Emmanuel; Valladares, Roberto; Zwingenberger, Stefan; Smith, R. Lane; Goodman, Stuart B.

2014-01-01

171

Light flash phenomena induced by HzE particles  

NASA Technical Reports Server (NTRS)

Astronauts and Apollo and Skylab missions have reported observing a variety of visual phenomena when their eyes are closed and adapted to darkness. These phenomena have been collectively labelled as light flashes. Visual phenomena which are similar in appearance to those observed in space have been demonstrated at the number of accelerator facilities by expressing the eyes of human subjects to beams of various types of radiation. In some laboratory experiments Cerenkov radiation was found to be the basis for the flashes observed while in other experiments Cerenkov radiation could apparently be ruled out. Experiments that differentiate between Cerenkov radiation and other possible mechanisms for inducing visual phenomena was then compared. The phenomena obtained in the presence and absence of Cerenkov radiation were designed and conducted. A new mechanism proposed to explain the visual phenomena observed by Skylab astronauts as they passed through the South Atlantic Anomaly, namely nuclear interactions in and near the sensitive layer of the retina, is covered. Also some studies to search for similar transient effects of space radiation on sensors and microcomputer memories are described.

Mcnulty, P. J.; Pease, V. P.

1980-01-01

172

Molecular basis of asbestos-induced lung disease.  

PubMed

Asbestos causes asbestosis and malignancies by molecular mechanisms that are not fully understood. The modes of action underlying asbestosis, lung cancer, and mesothelioma appear to differ depending on the fiber type, lung clearance, and genetics. After reviewing the key pathologic changes following asbestos exposure, we examine recently identified pathogenic pathways, with a focus on oxidative stress. Alveolar epithelial cell apoptosis, which is an important early event in asbestosis, is mediated by mitochondria- and p53-regulated death pathways and may be modulated by the endoplasmic reticulum. We review mitochondrial DNA (mtDNA)-damage and -repair mechanisms, focusing on 8-oxoguanine DNA glycosylase, as well as cross talk between reactive oxygen species production, mtDNA damage, p53, OGG1, and mitochondrial aconitase. These new insights into the molecular basis of asbestos-induced lung diseases may foster the development of novel therapeutic targets for managing degenerative diseases (e.g., asbestosis and idiopathic pulmonary fibrosis), tumors, and aging, for which effective management is lacking. PMID:23347351

Liu, Gang; Cheresh, Paul; Kamp, David W

2013-01-24

173

Molecular Basis of Asbestos-Induced Lung Disease  

PubMed Central

Asbestos causes asbestosis and malignancies by molecular mechanisms that are not fully understood. The modes of action underlying asbestosis, lung cancer, and mesothelioma appear to differ depending on the fiber type, lung clearance, and genetics. After reviewing the key pathologic changes following asbestos exposure, we examine recently identified pathogenic pathways, with a focus on oxidative stress. Alveolar epithelial cell apoptosis, which is an important early event in asbestosis, is mediated by mitochondria- and p53-regulated death pathways and may be modulated by the endoplasmic reticulum. We review mitochondrial DNA (mtDNA)-damage and -repair mechanisms, focusing on 8-oxoguanine DNA glycosylase, as well as cross talk between reactive oxygen species production, mtDNA damage, p53, OGG1, and mitochondrial aconitase. These new insights into the molecular basis of asbestos-induced lung diseases may foster the development of novel therapeutic targets for managing degenerative diseases (e.g., asbestosis and idiopathic pulmonary fibrosis), tumors, and aging, for which effective management is lacking. PMID:23347351

Liu, Gang; Cheresh, Paul; Kamp, David W.

2013-01-01

174

Castration Induces Parkinson Disease Pathologies in Young Male Mice via Inducible Nitric-oxide Synthase*  

PubMed Central

Although Parkinson disease (PD) is a progressive neurodegenerative disorder, available animal models do not exhibit irreversible neurodegeneration, and this is a major obstacle in finding out an effective drug against this disease. Here we delineate a new irreversible model to study PD pathogenesis. The model is based on simple castration of young male mice. Levels of inducible nitric-oxide synthase (iNOS), glial markers (glial fibrillary acidic protein and CD11b), and ?-synuclein were higher in nigra of castrated male mice than normal male mice. On the other hand, after castration, the level of glial-derived neurotrophic factor (GDNF) markedly decreased in the nigra of male mice. Accordingly, castration also induced the loss of tyrosine hydroxylase-positive neurons in the nigra and decrease in tyrosine hydroxylase-positive fibers and neurotransmitters in the striatum. Reversal of nigrostriatal pathologies in castrated male mice by subcutaneous implantation of 5?-dihydrotestosterone pellets validates an important role of male sex hormone in castration-induced nigrostriatal pathology. Interestingly, castration was unable to cause glial activation, decrease nigral GDNF, augment the death of nigral dopaminergic neurons, induce the loss of striatal fibers, and impair neurotransmitters in iNOS?/? male mice. Furthermore, we demonstrate that iNOS-derived NO is responsible for decreased expression of GDNF in activated astrocytes. Together, our results suggest that castration induces nigrostriatal pathologies via iNOS-mediated decrease in GDNF. These results are important because castrated young male mice may be used as a simple, toxin-free, and nontransgenic animal model to study PD-related nigrostriatal pathologies, paving the way for easy drug screening against PD. PMID:23744073

Khasnavis, Saurabh; Ghosh, Anamitra; Roy, Avik; Pahan, Kalipada

2013-01-01

175

Mitochondrial permeability transition pore induces mitochondria injury in Huntington disease  

PubMed Central

Background Mitochondrial impairment has been implicated in the pathogenesis of Huntington’s disease (HD). However, how mutant huntingtin impairs mitochondrial function and thus contributes to HD has not been fully elucidated. In this study, we used striatal cells expressing wild type (STHdhQ7/Q7) or mutant (STHdhQ111/Q111) huntingtin protein, and cortical neurons expressing the exon 1 of the huntingtin protein with physiological or pathological polyglutamine domains, to examine the interrelationship among specific mitochondrial functions. Results Depolarization induced by KCl resulted in similar changes in calcium levels without compromising mitochondrial function, both in wild type and mutant cells. However, treatment of mutant cells with thapsigargin (a SERCA antagonist that raises cytosolic calcium levels), resulted in a pronounced decrease in mitochondrial calcium uptake, increased production of reactive oxygen species (ROS), mitochondrial depolarization and fragmentation, and cell viability loss. The mitochondrial dysfunction in mutant cells was also observed in cortical neurons expressing exon 1 of the huntingtin protein with 104 Gln residues (Q104-GFP) when they were exposed to calcium stress. In addition, calcium overload induced opening of the mitochondrial permeability transition pore (mPTP) in mutant striatal cells. The mitochondrial impairment observed in mutant cells and cortical neurons expressing Q104-GFP was prevented by pre-treatment with cyclosporine A (CsA) but not by FK506 (an inhibitor of calcineurin), indicating a potential role for mPTP opening in the mitochondrial dysfunction induced by calcium stress in mutant huntingtin cells. Conclusions Expression of mutant huntingtin alters mitochondrial and cell viability through mPTP opening in striatal cells and cortical neurons. PMID:24330821

2013-01-01

176

DIESEL EXHAUST PARTICLE INDUCED GENE EXPRESSION CHANGES IN A MURINE MUCOSAL SENSITIZATION MODEL  

EPA Science Inventory

Studies in humans and animals have shown diesel exhaust particles (DEP) can act as an immunological adjuvant to enhance the development of allergic lung disease and this effect is influenced by the chemical composition of the DEP. The adjuvancy of NIST SRM 2975 (NDEP) generated...

177

Moving force of metal particle migration induced by laser irradiation in borosilicate glass.  

PubMed

We optically manipulated a metal particle in borosilicate glass. The glass in the neighborhood of the laser-heated metal particle softened; hence, the metal particle was able to migrate in the glass. In this letter, the driving force of the metal particle toward the light source in the glass provided by laser illumination was investigated. The variation in the surface tension of the glass at the interface between the glass and the metal particle induced by the temperature gradient was calculated via a numerical temperature calculation. It was found that the temperature at the laser-illuminated surface of a stainless-steel particle with a radius of 40 ?m was ~320 K higher than that on the nonilluminated side. The force applied to the metal particle from the surrounding glass was calculated to be ~100 ?N, which was approximately equal to the viscous resistance force. In addition, the experimental and numerically calculated speeds of the moving particle, which was measured while varying the laser power, are discussed. PMID:23938809

Hidai, Hirofumi; Matsushita, Makoto; Matsusaka, Souta; Chiba, Akira; Morita, Noboru

2013-08-12

178

Fluid-Induced Propulsion of Rigid Particles in Wormlike Micellar Solutions  

E-print Network

In the absence of inertia, a reciprocal swimmer achieves no net motion in a viscous Newtonian fluid. Here, we investigate the ability of a reciprocally actuated particle to translate through a complex fluid that possesses a network using tracking methods and birefringence imaging. A geometrically polar particle, a rod with a bead on one end, is reciprocally rotated using magnetic fields. The particle is immersed in a wormlike micellar (WLM) solution that is known to be susceptible to the formation of shear bands and other localized structures due to shear-induced remodeling of its microstructure. Results show that the nonlinearities present in this WLM solution break time-reversal symmetry under certain conditions, and enable propulsion of an artificial "swimmer." We find three regimes dependent on the Deborah number (De): net motion towards the bead-end of the particle at low De, net motion towards the rod-end of the particle at intermediate De, and no appreciable propulsion at high De. At low De, where the particle time-scale is longer then the fluid relaxation time, we believe that propulsion is caused by an imbalance in the fluid first normal stress differences between the two ends of the particle (bead and rod). At De~1, however, we observe the emergence of a region of network anisotropy near the rod using birefringence imaging. This anisotropy suggests alignment of the micellar network, which is "locked in" due to the shorter time-scale of the particle relative to the fluid.

David A. Gagnon; Nathan C. Keim; Xiaoning Shen; Paulo E. Arratia

2014-02-20

179

Fluid-induced propulsion of rigid particles in wormlike micellar solutions  

NASA Astrophysics Data System (ADS)

In the absence of inertia, a reciprocal swimmer achieves no net motion in a viscous Newtonian fluid. Here, using tracking methods and birefringence imaging, we investigate the ability of a reciprocally actuated particle to translate through a complex fluid that possesses a network. A geometrically polar particle, a rod with a bead on one end, is reciprocally rotated using magnetic fields. The particle is immersed in a wormlike micellar (WLM) solution that is known to be susceptible to the formation of shear bands and other localized structures due to shear-induced remodeling of its microstructure. Results show that the nonlinearities present in this WLM solution break time-reversal symmetry under certain conditions, and enable propulsion of an artificial "swimmer." We find three regimes dependent on the Deborah number (De): net motion towards the bead-end of the particle at low De, net motion towards the rod-end of the particle at intermediate De, and no appreciable propulsion at high De. At low De, where the particle time scale is longer than the fluid relaxation time, we believe that propulsion is caused by an imbalance in the fluid first normal stress differences between the two ends of the particle (bead and rod). At De ˜ 1, however, we observe the emergence of a region of network anisotropy near the rod using birefringence imaging. This anisotropy suggests alignment of the micellar network, which is "locked in" due to the shorter time scale of the particle relative to the fluid.

Gagnon, David A.; Keim, Nathan C.; Shen, Xiaoning; Arratia, Paulo E.

2014-10-01

180

Particle-Induced Desorption of Kilodalton Molecules Embedded in a Matrix: A Molecular Dynamics Study  

E-print Network

Particle-Induced Desorption of Kilodalton Molecules Embedded in a Matrix: A Molecular Dynamics and the mechanistic analysis of representative trajectories help us understand the main features of molecular significantly progressed with the development of sophisticated molecular dynamics (MD) simulation codes.1

181

Numerical Simulation of Intercalation-Induced Stress in Li-Ion Battery Electrode Particles  

E-print Network

Numerical Simulation of Intercalation-Induced Stress in Li-Ion Battery Electrode Particles in lithium-ion cells. Because of the presently unknown contributions of manufacturing and intercalation and manufacturing methods for these cells. Both global and localized loads must be estimated, in order to select

Sastry, Ann Marie

182

VISUALIZING THE FLOW INDUCED BY AN AIR CURTAIN OVER A MANNEQUIN USING STEREO PARTICLE IMAGE VELOCIMETRY  

E-print Network

VELOCIMETRY by JOHN EDWARD FERNANDES Presented to the Faculty of the Graduate School of The University image velocimetry system. Without his guidance, I would be far from done with my experimental work. I INDUCED BY AN AIR CURTAIN OVER A MANNEQUIN USING STEREO PARTICLE IMAGE VELOCIMETRY John Edward Fernandes

Texas at Arlington, University of

183

DIESEL AND CARBON PARTICLES ENHANCE HOUSE DUST MITE-INDUCED PULMONARY HYPERSENSITIVITY IN BROWN NORWAY RATS  

EPA Science Inventory

Diesel and Carbon Particles Enhance House Dust Mite-Induced Pulmonary Hypersensitivity in Brown Norway Rats. P. Singh1, M.J. Daniels2, D. Winsett2, J. Richards2, K. Crissman2, M. Madden2 and M.I. Gilmour2. 1NCSU, Raleigh, NC and 2 USEPA, Research Triangle Park, NC. Ep...

184

URBAN PARTICLE-INDUCED PULMONARY ARTERY CONSTRUCTION IS MEDIATED BY SUPEROXIDE PRODUCTION  

EPA Science Inventory

URBAN PARTICLE-INDUCED PULMONARY ARTERY CONSTRICTION IS MEDIATED BY SUPEROXIDE PRODUCTION.Jacqueline D. Carter, Zhuowei Li, Lisa A. Dailey, Yuh-Chin T. Huang. CEMALB, University of North Carolina, and ORD, US EPA, Chapel Hill, North Carolina. Exposure to particulate matter...

185

Particle Induced X-Ray Emission Analysis of Atmospheric Aerosols Collected in Upstate New York  

Microsoft Academic Search

Elemental analysis of atmospheric aerosols collected in the historic Stockade District of Schenectady, New York, was performed using particle induced X-ray emission (PIXE) spectroscopy. This is part of a systematic study in the Mohawk River Valley of upstate New York to identify the sources and understand the transport, transformation, and effects of airborne pollutants and the connection between aerosols, the

Colin Gleason; Charles Harrington; Katie Schuff; Scott Labrake; Michael Vineyard

2009-01-01

186

Manipulation of micro-particles by flexible polymer-based optically-induced dielectrophoretic devices.  

PubMed

This study presents a novel technology to manipulate micro-particles with the assistance from flexible polymer-based optically-induced dielectrophoretic (ODEP) devices. Bending the flexible ODEP devices downwards or upwards to create convex or concave curvatures, respectively, enables the more effective separation or collection of micro-particles with different diameters. The travel distances of the polystyrene beads of 40 ?m diameter, as induced by the projected light in a given time period was increased by ~100%, which were 43.0 ± 5.0 and 84.6 ± 4.0 ?m for flat and convex ODEP devices, respectively. A rapid separation or collection of micro-particles can be achieved with the assistance of gravity because the falling polystyrene beads followed the inclination of the downward and upward bent ODEP devices. PMID:22274380

Lin, Shu-Ju; Hung, Shih-Hsun; Jeng, Jun-Yuan; Guo, Tzung-Fang; Lee, Gwo-Bin

2012-01-01

187

Particle irradiation induces FGF2 expression in normal human lens cells  

NASA Technical Reports Server (NTRS)

Particle Irradiation Induces FGF2 Expression in Normal Human Lens Cells. Particle radiations, including both proton and helium-ion beams, have been used to successfully treat choroidal melanoma, but with the complication of radiation-induced cataract. We have investigated a role for radiation-induced changes in the expression of basic fibroblast growth factor (FGF2) gene expression as part of the mechanism(s) underlying lens cell injury associated with cataract. Normal human lens epithelial (HLE) cells were cultured in vitro on extracellular matrix (ECM) originated from bovine corneal endothelial cells. This study reports evidence for rapid but transient induction of FGF2 transcripts, an increase of between 5- and 8-fold, within 0.5 h after exposure to particle radiation, followed by another wave of increased transcription at 2-3 h postirradiation. Immunofluorescence results confirm the enhanced levels of FGF2 protein rapidly after exposure to protons or helium ions, followed by another wave of increased activity unique to helium at 6 h postirradiation. This second wave of increased immunoreactivity was not observed in the proton-irradiated samples. Total FGF2 protein analysis after helium-ion exposures shows induced expression of three FGF2 isoforms, with an increase of up to 2-fold in the 18-kDa low-molecular-weight species. Studies of the effects of protons on individual FGF2 protein isoforms are in progress. Several mechanisms involving a role for FGF2 in radiation-induced cataract are discussed.

Chang, P. Y.; Bjornstad K, A.; Chang, E.; McNamara, M.; Barcellos-Hoff, M. H.; Lin, S. P.; Aragon, G.; Polansky, J. R.; Lui, G. M.; Blakely, E. A.

2000-01-01

188

Mechanism of production of light complex particles in nucleon-induced reactions  

E-print Network

The Improved Quantum Molecular Dynamics (ImQMD) model incorporated with the statistical decay model is successful in describing emission of nucleons in the intermediate energy spallation reactions, but not good enough in describing productions of light complex particles, i.e. $d$, $t$, $^3$He and $^4$He. To improve the description on emission of light complex particles, a phenomenological mechanism called surface coalescence and emission is introduced into ImQMD model: nucleon ready to escape from the compound nuclei can coalesce with the other nucleon(s) to form light complex particle and be emitted. With updated ImQMD model, the description on the experimental data of light complex particles produced in nucleon-induced reactions are great improved.

Dexian Wei; Ning Wang; Li Ou

2013-09-29

189

Asian dust storm particles induce a broad toxicological transcriptional program in human epidermal keratinocytes.  

PubMed

Exposure to airborne dust particles originated from seasonal Asian dust storms in Chinese and Mongolian deserts results in increased incidence of a range of diseases including asthma, contact dermatitis and conjunctivitis. The areas affected by Asian dust particles extend from East China to the west coast of North America. In order to study toxicological mechanisms in human skin, we evaluated the effects of dust particles collected during Asian dust storms (Asian dust particles) on gene expression in human epidermal keratinocytes (HEK). In HEK, exposure to Asian dust particles significantly increased gene expressions of cytochrome P450 1A1 (CYP1A1), CYP1A2, and CYP1B1, which is an indication of aryl hydrocarbon receptor (AHR) activation. In addition, Asian dust particles increased gene transcription of the cytokines IL-6, IL-8, and GM-CSF, which have broad pro-inflammatory and immunomodulatory properties. Asian dust particles significantly up-regulated expression of caspase 14 in HEK, suggesting that Asian dust particles directly affect keratinocyte differentiation. We also demonstrated that protein extract of pollen, a material frequently adsorbed onto Asian dust particles, potentially contributes to the increased transcription of IL-6, CYP1A1, CYP1A2, and CYP1B1. Taken together, these studies suggest that Asian dust particles can exert toxicological effects on human skin through the activation of the cellular detoxification system, the production of pro-inflammatory and immunomodulatory cytokines, and changes in the expression of proteins essential in normal epidermal differentiation. PMID:21056094

Choi, Hyun; Shin, Dong Wook; Kim, Wonnyon; Doh, Seong-Jae; Lee, Soo Hwan; Noh, Minsoo

2011-01-15

190

Turbulence-induced Relative Velocity of Dust Particles. II. The Bidisperse Case  

NASA Astrophysics Data System (ADS)

We extend our earlier work on turbulence-induced relative velocity between equal-size particles (Paper I, in this series) to particles of arbitrarily different sizes. The Pan & Padoan (PP10) model shows that the relative velocity between different particles has two contributions, named the generalized shear and acceleration terms, respectively. The generalized shear term represents the particles' memory of the spatial flow velocity difference across the particle distance in the past, while the acceleration term is associated with the temporal flow velocity difference on individual particle trajectories. Using the simulation of Paper I, we compute the root-mean-square relative velocity, langw 2rang1/2, as a function of the friction times, ?p1 and ?p2, of the two particles and show that the PP10 prediction is in satisfactory agreement with the data, confirming its physical picture. For a given ?p1 below the Lagrangian correlation time of the flow, T L, langw 2rang1/2 as a function of ?p2 shows a dip at ?p2 ~= ?p1, indicating tighter velocity correlation between similar particles. Defining a ratio f ? ?p, l/?p, h, with ?p, l and ?p, h the friction times of the smaller and larger particles, we find that langw 2rang1/2 increases with decreasing f due to the generalized acceleration contribution, which dominates at f <~ 1/4. At a fixed f, our model predicts that langw 2rang1/2 scales as \\tau _p,h^{1/2} for ?p, h in the inertial range of the flow, stays roughly constant for T L <~ ?p, h <~ T L/f, and finally decreases as \\tau _p,h^{-1/2} for ?p, h Gt T L/f. The acceleration term is independent of the particle distance, r, and reduces the r dependence of langw 2rang1/2 in the bidisperse case.

Pan, Liubin; Padoan, Paolo; Scalo, John

2014-08-01

191

Adjuvant effects of chitosan and calcium phosphate particles in an inactivated Newcastle disease vaccine.  

PubMed

The adjuvant activity of chitosan (CS) and calcium phosphate (CAP) particles was studied following intranasal (mucosal) administration to commercial chickens with inactivated Newcastle disease virus (NDV) vaccine. After three vaccinations with inactivated NDV in combination with CS or CAP an increase in antibody titers in blood and mucosal samples in chickens was observed when compared with the administration of NDV antigen only. A lower level of humoral immunity was observed in broiler chickens compared to layer-type birds. The CS-based vaccine demonstrated higher antigenic and protective activity following lethal challenge than the vaccine containing CAP. Because CS particles efficiently changed mucosal and humoral immunity and protective activity, CS may in the future be considered for use as a potential adjuvant for production of vaccines for poultry. PMID:24758112

Volkova, Marina A; Irza, Anna V; Chvala, Irina A; Frolov, Sergy F; Drygin, Vladimir V; Kapczynski, Darrell R

2014-03-01

192

Lateral aggregation induced by magnetic perturbations in a magnetorheological fluid based on non-Brownian particles.  

PubMed

A study of lateral aggregation, induced by an oscillatory field, in a magnetorheological fluid based on non-Brownian magnetic particles is presented. We investigate the behavior of chains formed by the particles, due to the simultaneous application of a static magnetic field and a sinusoidal magnetic field transverse to each other. We show that the effective oscillating field enhances the aggregation process. We discuss this result in terms of an effective particle concentration induced by the oscillating field when chains oscillate angularly and sweep the area around them. The oscillating field produces a lateral aggregation similar to that observed in systems composed of Brownian particles which is induced by thermal fluctuations. We study the effect of the oscillating field on the angular amplitude described by single chains. It is observed that the angular amplitude decreases as the frequency of the oscillating field increases; we discuss this behavior numerically in terms of a simple model for this system. Lateral aggregation is studied in detail in isolated pairs of chains of equal length at several conditions of separation and displacement. From the results, a phase diagram is obtained showing the conditions under which aggregation is possible. PMID:24125266

Moctezuma, R E; Donado, F; Arauz-Lara, J L

2013-09-01

193

Purification, characterization and serological detection of virus-like particles associated with banana bunchy top disease in Australia  

Microsoft Academic Search

Isometric virus-like particles, 18 nm in diameter, have been isolated from banana (Musa spp.) affected by bunchy top disease in Australia. Banana bunchy top disease-associated virus-like particles (BBTV) banded as a single component with buoyant density of 1-28 to 1.29 g\\/ml in Cs2SO4 and sedimented at about 46S in isokinetic sucrose density gradients. The A260\\/.42S 0 of purified preparations was

John E. Thomas; Ralf G. Dietzgen

1991-01-01

194

A sandwiched flexible polymer mold for control of particle-induced defects in nanoimprint lithography  

NASA Astrophysics Data System (ADS)

Particle related defects are one of the key concerns for nanoimprint lithography, since the particle can amplify the defect to become much larger than the particle itself. We developed a flexible tri-layer mold for control of particle-induced defects. The mold was composed of a PDMS cushion layer sandwiched between a rigid imprint pattern layer and a plastic polyethylene terephthalate (PET) backplane. The PET foil was used as the backplane of the mold to protect the sticky PDMS surface. The PDMS as a cushion layer could locally deform to conform the shape of substrate due to its high elasticity. The multifunctional epoxysiloxane was used for the formation of an imprint layer because of its insensitivity toward oxygen during curing, high transparency, excellent mechanical strength and high resistance to oxygen plasma after cross-linking. Nanostructures with different geometries and sizes were faithfully duplicated by this mold through a UV-curing imprint process. The particle-induced defectivity was dramatically improved by the deformation of the PDMS cushion layer with a slight external pressure. 500 nm pitch grating structures were successfully imprinted on a microposts array surface, both the top and the intervening bottom portions between the microposts.

Li, Bin; Zhang, Jizong; Ge, Haixiong

2013-01-01

195

Prediction of Lung Cells Oncogenic Transformation for Induced Radon Progeny Alpha Particles Using Sugarscape Cellular Automata  

PubMed Central

Background Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Methods Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. Results The model results have successfully validated in comparison with “in vitro oncogenic transformation data” for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. Conclusion It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

2014-01-01

196

Quantitative elemental detection of size-segregated particles using laser-induced breakdown spectroscopy  

NASA Astrophysics Data System (ADS)

In order to simulate coal combustion and develop optimal and stable boiler control systems in real power plants, it is imperative to obtain the detailed information in coal combustion processes as well as to measure species contents in fly ash, which should be controlled and analyzed for enhancing boiler efficiency and reducing environmental pollution. The fly ash consists of oxides (SiO2, Al2O3, Fe2O3, CaO, and so on), unburned carbon, and other minor elements. Recently laser-induced breakdown spectroscopy (LIBS) technique has been applied to coal combustion and other industrial fields because of the fast response, high sensitivity, real-time and non-contact features. In these applications it is important to measure controlling factors without any sample preparation to maintain the real-time measurement feature. The relation between particle content and particle diameter is also one of the vital researches, because compositions of particles are dependent on their diameter. In this study, we have detected the contents of size-segregated particles using LIBS. Particles were classified by an Anderson cascade impactor and their contents were measured using the output of 1064 nm YAG laser, a spectrograph and an ICCD camera. The plasma conditions such as plasma temperature are dependent on the size of particles and these effects must be corrected to obtain quantitative information. The plasma temperature was corrected by the emission intensity ratio from the same atom. Using this correction method, the contents of particles can be measured quantitatively in fixed experimental parameters. This method was applied to coal and fly ash from a coal-fired burner to measure unburned carbon and other contents according to the particle diameter. The acquired results demonstrate that the LIBS technique is applicable to measure size-segregated particle contents in real time and this method is useful for the analysis of coal combustion and its control because of its sensitive and fast analysis features.

Wang, Zhen Zhen; Deguchi, Yoshihiro; Kuwahara, Masakazu; Taira, Takuya; Zhang, Xiao Bo; Yan, Jun Jie; Liu, Ji Ping; Watanabe, Hiroaki; Kurose, Ryoichi

2013-09-01

197

MATERNALLY INDUCED TRANSPLANTATION IMMUNITY, TOLERANCE, AND RUNT DISEASE IN RATS  

PubMed Central

A previous report that the offspring of outbred Sprague-Dawley rats, born of mothers presensitized or tolerant with respect to tissue antigens of the Lewis strain, and reinoculated with Lewis cells during their pregnancy, reject test grafts of Lewis skin in an accelerated manner has been confirmed. This "maternally induced" alteration in reactivity of the progeny has been found to be long lasting, immunologically specific, and probably not due to transfer of humoral antibody. It has been established that the reexposure of the mothers to donor cellular antigen during pregnancy augmented the influence of the prior states of tolerance or sensitivity. To obviate the complications inherent in working with the outbred Sprague-Dawley rats, the key experiments summarized above were repeated with isogenic Fischer rats as parents and Lewis rats as the tissue donors as before. With this combination it was found that a state of prior sensitization or tolerance in the mothers resulted in the apparent induction of tolerance in some of their progeny. Reinoculation of either the tolerant or sensitized mothers during pregnancy slightly increased the incidence and degree of impairment of their offsprings' capacity to reject Lewis skin grafts. A single intraperitoneal injection of 100 x 106 million Lewis lymphoid cells into normal Fischer rats in the 14th–16th day of pregnancy also weakened the reactivity of their progeny to Lewis test grafts. Further to test the premise that this weakened reactivity might be due to maternal induction of tolerance, by antenatal transmission of alien cells, the lymphohematopoietic tissue system of adult Fischer females was replaced by that from Lewis donors with the aid of cyclophosphamide. It was anticipated that when these animals were mated with Fischer males, sufficient Lewis leukocytes might cross the placentas to induce high degrees of tolerance. Although normal sized healthy litters were born, about 50% of the infants succumbed to graft-versus-host (GVH) or runt disease within 40 days, many of them giving evidence of being tolerant of Lewis grafts. The mothers, too, developed chronic GVH disease. The offspring of Fischer females made chimeric with cells from (Fischer x Lewis)F1 hybrid donors, as well as their mothers, remained healthy. Intraperitoneal injection of normal Fischer females, in the 15th–17th day of pregnancy, with 100 million lymphoid cells from specifically sensitized Lewis rats, also caused fatal runt disease to develop in about 50% of their offspring, but left the mothers unscathed. Taken together, these various findings indicate that in some genetic contexts at least the extent of the natural surreptitious transplacental cellular traffic can be considerably augmented experimentally, though how this comes about and why lymphocytic cells that are foreign to the mother can apparently gain access to fetuses more readily than her own cells remain to be determined. PMID:4553013

Beer, Alan E.; Billingham, R. E.; Yang, S. L.

1972-01-01

198

Comparison of fluorescence-based techniques for the quantification of particle-induced hydroxyl radicals  

Microsoft Academic Search

BACKGROUND: Reactive oxygen species including hydroxyl radicals can cause oxidative stress and mutations. Inhaled particulate matter can trigger formation of hydroxyl radicals, which have been implicated as one of the causes of particulate-induced lung disease. The extreme reactivity of hydroxyl radicals presents challenges to their detection and quantification. Here, three fluorescein derivatives [aminophenyl fluorescamine (APF), amplex ultrared, and dichlorofluorescein (DCFH)

Corey A Cohn; Sanford R Simon; Martin AA Schoonen

2008-01-01

199

Fiber Bragg grating filter using evaporated induced self assembly of silica nano particles  

NASA Astrophysics Data System (ADS)

In the present work we conduct a study of fiber filters produced by evaporation of silica particles upon a MM-fiber core. A band filter was designed and theoretically verified using a 2D Comsol simulation model of a 3D problem, and calculated in the frequency domain in respect to refractive index. The fiber filters were fabricated by stripping and chemically etching the middle part of an MM-fiber until the core was exposed. A mono layer of silica nano particles were evaporated on the core using an Evaporation Induced Self-Assembly (EISA) method. The experimental results indicated a broader bandwidth than indicated by the simulations which can be explained by the mismatch in the particle size distributions, uneven particle packing and finally by effects from multiple mode angles. Thus, there are several closely connected Bragg wavelengths that build up the broader bandwidth. The experimental part shows that it is possible by narrowing the particle size distributing and better control of the particle packing, the filter effectiveness can be greatly improved.

Hammarling, Krister; Zhang, Renyung; Manuilskiy, Anatoliy; Nilsson, Hans-Erik

2014-03-01

200

The cellular composition of induced sputum in chronic obstructive pulmonary disease  

Microsoft Academic Search

The cellular composition of induced sputum in chronic obstructive pulmonary disease. R.A. Peleman, P.H. Rytila ¨, J.C. Kips, G.F. Joos, R.A. Pauwels. #ERS Journals Ltd 1999. ABSTRACT: Asthma and chronic obstructive pulmonary disease are characterized by airway inflammation, which can be assessed by bronchoscopic techniques as well as by the analysis of induced sputum. A method to induce sputum with

R. A. Peleman; P. H. Rytilä; J. C. Kips; G. F. Joos; R. A. Pauwels

1999-01-01

201

Quantification of particle-induced inflammatory stress response: a novel approach for toxicity testing of earth materials  

PubMed Central

Background Reactive oxygen species (ROS) are vital regulators of many cellular functions in the body. The intracellular ROS concentration is highly regulated by a balance between pro-oxidants and anti-oxidants. A chronic excess of pro-oxidants leads to elevated ROS concentrations and inflammation, possibly initiating or enhancing disease onset. Mineral-induced generation of ROS, the role of minerals in upregulating cellular ROS, and their role in the development of several occupational diseases are now widely recognized. However, there is no standard protocol to determine changes in ROS production in cells after exposure to mineral dust or earth materials in general. In this study, a new method for determining the degree of cellular toxicity (i.e., cytotoxicity) of particles is described that will help bridge the gap in knowledge. Results By measuring the production of ROS and the viability of cells, an inflammatory stress response (ISR) indicator is defined. This approach normalizes the ROS upregulation with respect to the number of viable cells at the time of measurement. We conducted experiments on a series of minerals and soils that represent materials that are inert (i.e., glass beads, anatase, and a soil with low trace element content), moderately reactive (i.e., soil with high trace element content), and highly reactive (i.e., pyrite). Inert materials generated the lowest ISR, averaging 350% compared to the control. Acid washed pyrite produced the highest ISR (1,100 fold higher than the control). The measurements conducted as a function of time showed a complex response. Most materials showed an increase in ISR with particle loading. Conclusions The amount of cellularly generated ROS and cell viability combined provide a better understanding of particle-induced oxidative stress. The results indicate that some earth materials may solicit an initial burst of ROS, followed by a second phase in which cell viability decreases and ROS production increases, leading to a high ISR value. Hence, measurements conducted over a range of particle loading combined with multiple data measurements up to 24 hours can provide new insights in the possible effect of exposure to earth materials on human health. PMID:22513118

2012-01-01

202

DISEASE-SPECIFIC SUSCEPTIBILITY TO ACUTE OZONE-INDUCED INJURY AND INFLAMMATION IN EIGHT RAT STRAINS  

EPA Science Inventory

Susceptibility to environmental pollutant-induced injuries may be influenced by presence of disease and genetic make-up. To identify disease-specific susceptibility phenotype, we used eight rat strains with or without genetic cardiovascular disease. Male 12-15 wk old Sprague Dawl...

203

Ebola virus VP40-induced particle formation and association with the lipid bilayer.  

PubMed

Viral protein 40 (VP40) of Ebola virus appears equivalent to matrix proteins of other viruses, yet little is known about its role in the viral life cycle. To elucidate the functions of VP40, we investigated its ability to induce the formation of membrane-bound particles when it was expressed apart from other viral proteins. We found that VP40 is indeed able to induce particle formation when it is expressed in mammalian cells, and this process appeared to rely on a conserved N-terminal PPXY motif, as mutation or loss of this motif resulted in markedly reduced particle formation. These findings demonstrate that VP40 alone possesses the information necessary to induce particle formation, and this process most likely requires cellular WW domain-containing proteins that interact with the PPXY motif of VP40. The ability of VP40 to bind cellular membranes was also studied. Flotation gradient analysis indicated that VP40 binds to membranes in a hydrophobic manner, as NaCl at 1 M did not release the protein from the lipid bilayer. Triton X-114 phase-partitioning analysis suggested that VP40 possesses only minor features of an integral membrane protein. We confirmed previous findings that truncation of the 50 C-terminal amino acids of VP40 results in decreased association with cellular membranes and demonstrated that this deletion disrupts hydrophobic interactions of VP40 with the lipid bilayer, as well as abolishing particle formation. Truncation of the 150 C-terminal amino acids or 100 N-terminal amino acids of VP40 enhanced the protein's hydrophobic association with cellular membranes. These data suggest that VP40 binds the lipid bilayer in an efficient yet structurally complex fashion. PMID:11333902

Jasenosky, L D; Neumann, G; Lukashevich, I; Kawaoka, Y

2001-06-01

204

Wave-induced precipitation as a loss process for radiation belt particles  

NASA Astrophysics Data System (ADS)

Precipitation of radiation belt electrons by VLF waves injected from ground based transmitters was achieved during the Stimulated Emission of Energetic Particles (SEEP) experiments (Imhof et al., 1983), the first direct satellite based observation of modulated precipitation of electrons in the bounce loss cone. This paper considers the temporal and spectral shape as well as the absolute flux level of the observed precipitation pulses. In order to model these results, both the pitch angle dependence of the particle distribution near the edge of the loss cone and atmospheric backscatter which leads to multiple interactions of the particles with the wave are considered. Based on a comparison of theory with observations, the leverage of the precipitation process is estimated. Crude estimates of the percentage depletion of the radiation belt population due to the observed transmitter induced precipitation are also made.

Inan, U. S.; Chang, H. C.; Helliwell, R. A.; Katsufrakis, J. P.; Imhof, W. L.

205

Ebola Virus VP40Induced Particle Formation and Association with the Lipid Bilayer  

Microsoft Academic Search

Viral protein 40 (VP40) of Ebola virus appears equivalent to matrix proteins of other viruses, yet little is known about its role in the viral life cycle. To elucidate the functions of VP40, we investigated its ability to induce the formation of membrane-bound particles when it was expressed apart from other viral proteins. We found that VP40 is indeed able

LUKE D. JASENOSKY; GABRIELE NEUMANN; IGOR LUKASHEVICH; YOSHIHIRO KAWAOKA

2001-01-01

206

Diesel Exhaust Particles Enhance Antigen-induced Airway Inflammation and Local Cytokine Expression in Mice  

Microsoft Academic Search

Previous experimental studies have suggested that nasal instillation of diesel exhaust particles (DEP) can enhance nasal IgE response and cytokine production. However, there is no experimental evi- dence for the relation of DEP to allergic asthma. We investigated the effects of DEP inoculated in- tratracheally on antigen-induced airway inflammation, local expression of cytokine proteins, and antigen-specific immunoglobulin production in mice.

HIROHISA TAKANO; TOSHIKAZU YOSHIKAWA; TAKAMICHI ICHINOSE; YUICHI MIYABARA; KOICHI IMAOKA; MASARU SAGAI

1997-01-01

207

Effects of ultrafine particles-induced oxidative stress on Clara cells in allergic lung inflammation  

Microsoft Academic Search

BACKGROUND: Clara cell protein (CC16), the main secretory product of bronchiolar Clara cells, plays an important protective role in the respiratory tract against oxidative stress and inflammation. The purpose of the study was to investigate the role of elemental carbon ultrafine particles (EC-UFP)-induced oxidative stress on Clara cells and CC16 in a mouse model of allergic lung inflammation. METHODS: Ovalbumin

Francesca Alessandrini; Ingrid Weichenmeier; Erik van Miert; Shinji Takenaka; Erwin Karg; Cornelia Blume; Martin Mempel; Holger Schulz; Alfred Bernard; Heidrun Behrendt

2010-01-01

208

On inducing finite dimensional physical field representations for massless particles in even dimensions  

NASA Technical Reports Server (NTRS)

Assuming trivial action of Euclidean translations, the method of induced representations is used to derive a correspondence between massless field representations transforming under the full generalized even dimensional Lorentz group, and highest weight states of the relevant little group. This gives a connection between 'helicity' and 'chirality' in all dimensions. Restrictions on 'gauge independent' representations for physical particles that this induction imposes are also stated.

Bhansali, Vineer

1993-01-01

209

Mutilocus genetic determinants of LDL particle size in coronary artery disease families  

SciTech Connect

Recent interest in atherosclerosis has focused on the genetic determinants of low-density lipoprotein (LDL) particle size, because of (1) the association of small dense LDL particles with a three-fold increased risk for coronary artery disease (CAD) and (2) the recent report of linkage of the trait to the LDL receptor (chromosome 19). By utilizing nonparametric quantitative sib-pair and relative-pair-analysis methods in CAD families, we tested for linkage of a gene or genes controlling LDL particle sizes with the genetic loci for the major apolipoproteins and enzymes participating in lipoprotein metabolism. We confirmed evidence for linkage to the LDL receptor locus (P = .008). For six candidate gene loci, including apolipoprotein(apo)B, apoAII, apo(a), apoE-CI-CII, lipoprotein lipase, and high-density lipoprotein-binding protein, no evidence for linkage was observed by sib-pair linkage analyses (P values ranged from .24 to .81). However, in addition, we did find tentative evidence for linkage with the apoAI-CIII-AIV locus (chromosome 11) (P = .06) and significant evidence for linkage of the cholesteryl ester transfer protein locus (chromosome 16) (P = .01) and the manganese superoxide dismutase locus (chromosome 6) (P = .001), thus indicating multilocus determination of this atherogenic trait. 73 refs., 3 figs., 4 tabs.

Rotter, J.I.; Bu, X.; Cantor, R.M. [and others

1996-03-01

210

Polyethylene wear particles induce TLR 2 upregulation in the synovial layer of mice.  

PubMed

A cellular and receptor mediated response to ultra-high-molecular-weight-polyethylene (UHMWPE) wear particles results in a release of proinflammatory cytokines and induces an inflammatory reaction causing osteolysis in total joint replacement. This investigation offers insight into the toll-like receptor (TLR) mediated activation by polyethylene wear particles in the synovial layer of mice. We hypothesized that, similar to recent in vitro results, UHMWPE particles lead to an upregulation of TLR 1 and 2 and TLR 4 in vivo in the synovial tissue of mice as well. Therefore, UHMWPE particles were generated in a common knee simulator according to the ISO standard, separated by acid digestion and determined by scanning electron microscopy. Endotoxin was removed using a method based on ultracentrifugation. A particle suspension (50 ?l; 0.1 vol./vol.%) was injected into the left knee joint of female Balb/c mice (n = 8). In a control group, phosphate-buffered saline was injected into the left knee of Balb/c mice (n = 8). The mice were sacrificed after 7 days. Immunohistochemical staining was performed with TLR 1, 2 and 4 polyclonal antibodies for Balb/c mice and evaluated by light microscopy. The particle-stimulated group showed a thickened synovial layer, an increased cellular infiltration and a TLR 2-upregulation in the synovial layer compared to the control group. An increased expression of TLR 1 and TLR 4 could not be demonstrated. These results indicate a mainly TLR 2-induced inflammation to polyethylene wear debris in the synovial layer of mice. PMID:24249629

Paulus, A C; Frenzel, J; Ficklscherer, A; Roßbach, B P; Melcher, C; Jansson, V; Utzschneider, S

2014-02-01

211

Exposure to Concentrated Ambient Particles Does Not Affect Vascular Function in Patients with Coronary Heart Disease  

PubMed Central

Background Exposure to fine particulate air pollution is associated with increased cardiovascular morbidity and mortality. We previously demonstrated that exposure to dilute diesel exhaust causes vascular dysfunction in humans. Objectives We conducted a study to determine whether exposure to ambient particulate matter causes vascular dysfunction. Methods Twelve male patients with stable coronary heart disease and 12 age-matched volunteers were exposed to concentrated ambient fine and ultrafine particles (CAPs) or filtered air for 2 hr using a randomized, double-blind cross-over study design. We measured peripheral vascular vasomotor and fibrinolytic function, and inflammatory variables—including circulating leukocytes, serum C-reactive protein, and exhaled breath 8-isoprostane and nitrotyrosine—6–8 hr after both exposures. Results Particulate concentrations (mean ± SE) in the exposure chamber (190 ± 37 ?g/m3) were higher than ambient levels (31 ± 8 ?g/m3) and levels in filtered air (0.5 ± 0.4 ?g/m3; p < 0.001). Chemical analysis of CAPs identified low levels of elemental carbon. Exhaled breath 8-isoprostane concentrations increased after exposure to CAPs (16.9 ± 8.5 vs. 4.9 ± 1.2 pg/mL, p < 0.05), but markers of systemic inflammation were largely unchanged. Although there was a dose-dependent increase in blood flow and plasma tissue plasminogen activator release (p < 0.001 for all), CAPs exposure had no effect on vascular function in either group. Conclusions Despite achieving marked increases in particulate matter, exposure to CAPs—low in combustion-derived particles—did not affect vasomotor or fibrinolytic function in either middle-aged healthy volunteers or patients with coronary heart disease. These findings contrast with previous exposures to dilute diesel exhaust and highlight the importance of particle composition in determining the vascular effects of particulate matter in humans. PMID:18560524

Mills, Nicholas L.; Robinson, Simon D.; Fokkens, Paul H. B.; Leseman, Daan L. A. C.; Miller, Mark R.; Anderson, David; Freney, Evelyn J.; Heal, Mathew R.; Donovan, Robert J.; Blomberg, Anders; Sandstrom, Thomas; MacNee, William; Boon, Nicholas A.; Donaldson, Ken; Newby, David E.; Cassee, Flemming R.

2008-01-01

212

Particles from wood smoke and traffic induce differential pro-inflammatory response patterns in co-cultures  

SciTech Connect

The inflammatory potential of particles from wood smoke and traffic has not been well elucidated. In this study, a contact co-culture of monocytes and pneumocytes was exposed to 10-40 {mu}g/cm{sup 2} of particles from wood smoke and traffic for 12, 40 and 64 h to determine their influence on pro-inflammatory cytokine release (TNF-{alpha}, IL-1, IL-6, IL-8) and viability. To investigate the role of organic constituents in cytokine release the response to particles, their organic extracts and the washed particles were compared. Antagonists were used to investigate source-dependent differences in intercellular signalling (TNF-{alpha}, IL-1). The cytotoxicity was low after exposure to particles from both sources. However, wood smoke, and to a lesser degree traffic-derived particles, induced a reduction in cell number, which was associated with the organic fraction. The release of pro-inflammatory cytokines was similar for both sources after 12 h, but traffic induced a greater release than wood smoke particles with increasing exposure time. The organic fraction accounted for the majority of the cytokine release induced by wood smoke, whereas the washed traffic particles induced a stronger response than the corresponding organic extract. TNF-{alpha} and IL-1 antagonists reduced the release of IL-8 induced by particles from both sources. In contrast, the IL-6 release was only reduced by the IL-1 antagonist during exposure to traffic-derived particles. In summary, particles from wood smoke and traffic induced differential pro-inflammatory response patterns with respect to cytokine release and cell number. Moreover, the influence of the organic particle fraction and intercellular signalling on the pro-inflammatory response seemed to be source-dependent.

Kocbach, Anette [Division of Environmental Medicine, Norwegian Institute of Public Health, Geitemyrsveien 75, 0462 Oslo (Norway)], E-mail: anette.kocbach@fhi.no; Herseth, Jan Inge [Biomedical Laboratory Science, Faculty of Health Sciences, Oslo University College, Pilestredet 50, 0167 Oslo (Norway); Lag, Marit; Refsnes, Magne; Schwarze, Per E. [Division of Environmental Medicine, Norwegian Institute of Public Health, Geitemyrsveien 75, 0462 Oslo (Norway)

2008-10-15

213

Smad7 foci are present in micronuclei induced by heavy particle radiation.  

PubMed

DNA damage and reactive oxygen species (ROS) generated by ionizing radiation (IR) activate DNA damage response (DDR) and cytokine signaling pathways, including double strand break (DSB) repair and TGF?/Smad signaling pathway. Proteins assembled at IR-induced DSB sites can be visualized as foci, including ?H2AX, 53BP1, ATM and ATF2. Unrepaired DSBs are thought to be one origin of micronuclei (MN), an indicator of genotoxic stress and chromosomal instability. Studies have detected ?H2AX in IR-induced MN, indicating the presence of DSB in MN. Previously we reported that TGF? downstream proteins Smad7 and phospho-Smad2 (pSmad2) co-localized with DDR proteins following radiation. Here we studied the status of Smad7 and pSmad2 in MN post high linear energy transfer (LET) radiation in human normal and cancerous cells. We observed ?H2AX foci in IR-induced MN, whereas 53BP1 and ATF2 were absent. Interestingly, Smad7 foci, but not pSmad2, were detectable in both spontaneous and IR-induced MN. We compared the effect of particle track structures on the yield of MN using 5.6MeV/u boron (B) and 600MeV/u iron (Fe) particles with similar LET (200 and 180keV/?m, respectively) in human fibroblasts. The frequency of MN induced by B was lower than that by Fe particles, albeit the proportion of Smad7-positive to Smad7-negative MN remained constant. An increased frequency of spontaneous MN, with slightly higher ratio of Smad7 or ?H2AX positive, was found in human prostate cancer cells (PC3) compared to normal cells. 24h after 1Gy of Fe particles exposure, the yield of MN increased, and the majority (?70%) carried ?H2AX and Smad7. Phospho-ATM (Ser1981) foci were found in both spontaneous and IR-induced MN in PC3 cells, displaying a much lower frequency compared to ?H2AX and Smad7. Our data suggest a unique role of Smad7 in IR-induced MN formation, which may associate with DNA repair, apoptosis and genomic instability. PMID:23643526

Wang, Minli; Saha, Janapriya; Cucinotta, Francis A

2013-08-30

214

Electric field-induced motion of solid particles in two-dimensional fluids  

NASA Astrophysics Data System (ADS)

Electric field induced motion of spherical and cylindrical glass particles were studied in a smectic A liquid crystal octyl cyanobiphenyl (8CB) medium. The particles were dispersed in the smectic A medium, sandwiched between to glass plates with conductive inner surfaces. Under DC fields the smectic layers become parallel to the glass substrates. Such configuration corresponds to a two dimensional isotropic fluid structure along the film surface: the motion of solid particles results viscous forces along the substrates, whereas the motion across the layers is opposed by elastic permeation forces. Under DC fields above a threshold instability occurs and the particles move with constant speed in arbitrary directions normal to the electric field. The moving spheres and the cylinders rotate about their symmetry axis along the layers. When air bubbles are present in the film the, spheres tend to stick to the bubbles, and rotate collectively with a field- dependent speed that is independent of the radius of the bubbles (the angular velocity is inversely proportional to the radius). The details of the motion and the underlying physical mechanism will be discussed. The studies may have relevance of understanding particle motions in cell membranes under electric actuations and will contribute to our understanding of the hydrodynamic properties of two-dimensional fluid systems.

Jackli, Antal; Liao, Guangxun; Kelly, Jack R.

2004-03-01

215

Fine ambient particles induce oxidative stress and metal binding genes in human alveolar macrophages.  

PubMed

Exposure to pollutant particles increased respiratory morbidity and mortality. The alveolar macrophages (AMs) are one cell type in the lung directly exposed to particles. Upon contact with particles, AMs are activated and produce reactive oxygen species, but the scope of this oxidative stress response remains poorly defined. In this study, we determined the gene expression profile in human AMs exposed to particles, and sought to characterize the global response of pro- and antioxidant genes. We exposed AMs obtained by bronchoscopy from normal individuals to Chapel Hill particulate matter of 2.5-microm diameter or smaller (PM(2.5); 1 microg/ml) or vehicle for 4 hours (n = 6 independent samples). mRNAs were extracted, amplified, and hybridized to Agilent human 1A microarray. Significant genes were identified by significance analysis of microarrays (false discovery rate, 10%; P < or = 0.05) and mapped with Gene Ontology in the Database for Annotation, Visualization, and Integrated Discovery. We found 34 and 41 up- and down-regulated genes, respectively; 22 genes (approximately 30%) were involved in metal binding, and 11 were linked to oxidative stress, including up-regulation of five metallothionein (MT)-1 isoforms. Exogenous MT1 attenuated PM(2.5)-induced H2O2 release. PM(2.5) premixed with MT1 stimulated less H2O2 release. Knockdown of MT1F gene increased PM(2.5)-induced H2O2 release. PM(2.5) at 1 microg/ml did not increase H2O2 release. Mount St. Helens PM(2.5) and acid-extracted Chapel Hill PM(2.5), both poor in metals, did not induce MT1F or H2O2 release. Our results show that PM(2.5) induced a gene expression profile prevalent with genes related to metal binding and oxidative stress in human AMs, independent of oxidative stress. Metals associated with PM may play an important role in particle-induced gene changes. PMID:19251948

Huang, Yuh-Chin T; Li, Zhuowei; Carter, Jacqueline D; Soukup, Joleen M; Schwartz, David A; Yang, Ivana V

2009-11-01

216

Cellular and molecular analysis of mutagenesis induced by charged particles of defined linear energy transfer  

NASA Technical Reports Server (NTRS)

Mutation induction by charged particles of defined linear energy transfer (LET) and gamma rays was scored using human-hamster hybrid AL cells. The LET values for charged particles accelerated at the Radiological Research Accelerator Facility ranged from 10 keV/microm protons to 150 keV/microm 4He ions. The induced mutant fractions at both the S1 and HGPRT loci were dependent on the dose and LET. In addition, for each dose examined, the mutant yield at the S1 locus was 30-60 fold higher than at the corresponding HGPRT locus. To determine whether the mutation spectrum was comparably dependent on dose and LET, independent S1- and HGPRT- mutants induced by 150 keV/microm 4He ions and gamma rays were isolated, and their DNA was analyzed by both Southern blotting and multiplex PCR methods. While the majority of radiation-induced mutants showed deletions of varying sizes, the relative percentage of large deletions was found to be related to both the dose and LET of the radiation examined. Using a mutation system that can detect multilocus changes, results of the present study show that radiation-induced chromosomal loss can be in the millions of base pairs.

Zhu, L. X.; Waldren, C. A.; Vannias, D.; Hei, T. K.; Chatterjee, A. (Principal Investigator)

1996-01-01

217

Brain signaling and behavioral responses induced by exposure to (56)Fe-particle radiation  

NASA Technical Reports Server (NTRS)

Previous experiments have demonstrated that exposure to 56Fe-particle irradiation (1.5 Gy, 1 GeV) produced aging-like accelerations in neuronal and behavioral deficits. Astronauts on long-term space flights will be exposed to similar heavy-particle radiations that might have similar deleterious effects on neuronal signaling and cognitive behavior. Therefore, the present study evaluated whether radiation-induced spatial learning and memory behavioral deficits are associated with region-specific brain signaling deficits by measuring signaling molecules previously found to be essential for behavior [pre-synaptic vesicle proteins, synaptobrevin and synaptophysin, and protein kinases, calcium-dependent PRKCs (also known as PKCs) and PRKA (PRKA RIIbeta)]. The results demonstrated a significant radiation-induced increase in reference memory errors. The increases in reference memory errors were significantly negatively correlated with striatal synaptobrevin and frontal cortical synaptophysin expression. Both synaptophysin and synaptobrevin are synaptic vesicle proteins that are important in cognition. Striatal PRKA, a memory signaling molecule, was also significantly negatively correlated with reference memory errors. Overall, our findings suggest that radiation-induced pre-synaptic facilitation may contribute to some previously reported radiation-induced decrease in striatal dopamine release and for the disruption of the central dopaminergic system integrity and dopamine-mediated behavior.

Denisova, N. A.; Shukitt-Hale, B.; Rabin, B. M.; Joseph, J. A.

2002-01-01

218

Potential applications of magnetic particles to detect and treat Alzheimer's disease  

PubMed Central

Nanotechnology is an exciting and promising scientific discipline. At the nanoscale, a material displays novel physical properties that offer many new and beneficial products and applications. In particular, magnetic nanoparticles - a core/shell nanoparticle - present considerable diagnostic and therapeutic potentials, and superparamagnetic iron oxide nanoparticles (SPIONs) are considered promising theranostic tools. Alzheimer's disease (AD) is a neurodegenerative disorder that predominantly affects people over 65 years of age. The disease is characterized by the presence of extracellular plaques in the brain which are formed by interwoven fibrils composed of variants of the ?-amyloid peptide. Medication can temporarily retard worsening of symptoms, but only in the first stages of the disease; early detection is thus of crucial importance. This minireview covers the progress made in research on the use of magnetic nanoparticles for ex vivo and/or in vivo detection and diagnosis of AD by means of magnetic resonance imaging (MRI), or to label peptides and fibrils. Of particular importance is the use of these nanoparticles to detect AD biomarkers in biological fluids. A description is given of the bio-barcode amplification assay using functionalized magnetic particles, as well as the use of such nanoparticles as a system for inhibiting or delaying the assembly of peptide monomers into oligomers and fibrils. Lastly, a brief overview is given of possible future lines of research in this. PMID:25288921

2014-01-01

219

Toll-like receptors-2 and 4 are overexpressed in an experimental model of particle-induced osteolysis.  

PubMed

Aseptic loosening secondary to particle-associated periprosthetic osteolysis remains a major cause of failure of total joint replacements (TJR) in the mid- and long term. As sentinels of the innate immune system, macrophages are central to the recognition and initiation of the inflammatory cascade, which results in the activation of bone resorbing osteoclasts. Toll-like receptors (TLRs) are involved in the recognition of pathogen-associated molecular patterns and danger-associated molecular patterns. Experimentally, polymethylmethacrylate and polyethylene (PE) particles have been shown to activate macrophages via the TLR pathway. The specific TLRs involved in PE particle-induced osteolysis remain largely unknown. We hypothesized that TLR-2, -4, and -9 mediated responses play a critical role in the development of PE wear particle-induced osteolysis in the murine calvarium model. To test this hypothesis, we first demonstrated that PE particles caused observable osteolysis, visible by microCT and bone histomorphometry when the particles were applied to the calvarium of C57BL/6 mice. The number of TRAP positive osteoclasts was significantly greater in the PE-treated group when compared to the control group without particles. Finally, using immunohistochemistry, TLR-2 and TLR-4 were highly expressed in PE particle-induced osteolytic lesions, whereas TLR-9 was downregulated. TLR-2 and -4 may represent novel therapeutic targets for prevention of wear particle-induced osteolysis and accompanying TJR failure. PMID:24115330

Valladares, Roberto D; Nich, Christophe; Zwingenberger, Stefan; Li, Chenguang; Swank, Katherine R; Gibon, Emmanuel; Rao, Allison J; Yao, Zhenyu; Goodman, Stuart B

2014-09-01

220

Strontium ranelate inhibits titanium-particle-induced osteolysis by restraining inflammatory osteoclastogenesis in vivo.  

PubMed

Wear-particle-induced osteolysis is considered to be the main reason for revision after arthroplasty. Although the exact mechanism remains unclear, inflammatory osteoclastogenesis plays an important role in this process. Strontium ranelate (SR) was found to have a therapeutic effect on osteoporosis in postmenopausal women. Based on prior studies, the present authors hypothesized that SR prevents wear-particle-induced osteolysis through restraining inflammatory osteoclastogenesis. The present study used 80 male C57BL/J6 mice to test this hypothesis in a murine osteolysis model. All experimental animals were randomly divided into four groups: a control group; a SR group; a titanium group; and a titanium+SR group. Once titanium particles had been implanted in mice, the mice were administered SR (900mgkg(-1)day(-1)) by gavage for 14days. After 14days, the calvaria were collected for micro-computed tomography (?CT), histological and molecular analysis. The results of ?CT and histomorphometric analysis demonstrated that SR markedly inhibited bone resorption and the generation of tartrate-resistant acid-phosphatase-positive cells in vivo, compared with titanium-stimulated calvaria. Reverse transcription polymerase chain reaction and ELISAs showed that SR stimulated the mRNA and protein expression of osteoprotegerin, and inhibited gene and protein expression of receptor activators of nuclear factor-kappa B ligand in titanium-particle-charged calvaria. In addition, SR obviously reduced the secretion of tumor necrosis factor-? and interleukin-1? in the calvaria of the titanium group. It was concluded that SR inhibits titanium-induced osteolysis by restraining inflammatory osteoclastogenesis, and that it could be developed as a new drug to prevent and treat aseptic loosening. PMID:25078426

Liu, Xing; Zhu, Shijun; Cui, Jingfu; Shao, Hongguo; Zhang, Wen; Yang, Huilin; Xu, Yaozeng; Geng, Dechun; Yu, Long

2014-11-01

221

Therapeutic application of metallic nanoparticles combined with particle-induced x-ray emission effect  

NASA Astrophysics Data System (ADS)

Metallic nanoparticles (MNP) are able to release localized x-rays when activated with a high energy proton beam by the particle-induced x-ray emission (PIXE) effect. The exploitation of this phenomenon in the therapeutic irradiation of tumors has been investigated. PIXE-based x-ray emission directed at CT26 tumor cells in vitro, when administered with either gold (average diameter 2 and 13 nm) or iron (average diameter 14 nm) nanoparticles (GNP or SNP), increased with MNP solution concentration over the range of 0.1-2 mg ml - 1. With irradiation by a 45 MeV proton therapy (PT) beam, higher concentrations had a decreased cell survival fraction. An in vivo study in CT26 mouse tumor models with tumor regression assay demonstrated significant tumor dose enhancement, thought to be a result of the PIXE effect when compared to conventional PT without MNP (radiation-only group) using a 45 MeV proton beam (p < 0.02). Those receiving GNP or SNP injection doses of 300 mg kg - 1 body weight before proton beam therapy demonstrated 90% or 75% tumor volume reduction (TVR) in 20 days post-PT while the radiation-only group showed only 18% TVR and re-growth of tumor volume after 20 days. Higher complete tumor regression (CTR) was observed in 14-24 days after a single treatment of PT with an average rate of 33-65% for those receiving MNP compared with 25% for the radiation-only group. A lower bound of therapeutic effective MNP concentration range, in vivo, was estimated as 30-79 µg g - 1 tissue for both gold and iron nanoparticles. The tumor dose enhancement may compensate for an increase in entrance dose associated with conventional PT when treating large, solid tumors with a spread-out Bragg peak (SOBP) technique. The use of a combined high energy Bragg peak PT with PIXE generated by MNP, or PIXE alone, may result in new treatment options for infiltrative metastatic tumors and other diffuse inflammatory diseases.

Kim, Jong-Ki; Seo, Seung-Jun; Kim, Ki-Hong; Kim, Tae-Jeong; Chung, Myung-Hwan; Kim, Kye-Ryung; Yang, Tae-Keun

2010-10-01

222

Modeling fundamental plasma transport and particle-induced emission in a simplified Test Cell  

NASA Astrophysics Data System (ADS)

This work involves the modeling of fundamental plasma physics processes occurring within environments that are similar to that of the discharge and plume regions of electric propulsion devices such as Hall effect thrusters. The research is conducted as a collaborative effort with the Plasma & Space Propulsion Laboratory at the University of California, Los Angeles (UCLA), as part of the University of Michigan/AFRL Center for Excellence in Electric Propulsion (MACEEP). Transport physics, such as particle-particle collisions and particle-induced electron emission, are simulated within the UCLA experimental facility and its representative electric propulsion environment. Simulation methods employed include the direct simulation Monte Carlo (DSMC) and particle-in-cell (PIC) techniques for the kinetic simulation of charged, rarefied species on high-performance computing architectures. Momentum- (MEX) and charge-exchange (CEX) collision cross-section models for Xe and Xe+, both total and differential, are successfully validated at collision energies of ˜1.5 keV within the novel facility. Heavy-species collisional transport models are validated and the importance of scattering anisotropy in this collision-dominated environment is shown. The theory of particle-induced electron emission (PIE) is then investigated in the context of the relevant energies and environments of the UCLA facility and electric propulsion devices and diagnostics. Reduced, semi-empirical models for total yield and emitted electron energy distribution functions that are easily implemented in a DSMC-PIC code are developed for the simulation of secondary-electron emission due to low-energy ions and high-energy atoms, even in the case of incomplete target-material information. These models are important for the characterization of electric propulsion devices due to the problematic nature of low-temperature plasma diagnostic techniques in which the emission of electrons is physically indistinguishable from the collection of ions.

Giuliano, Paul Nicholas

223

Haemodialysis-induced myocardial stunning in chronic kidney disease - a new aspect of cardiovascular disease.  

PubMed

Chronic haemodialysis (HD) patients are already primed by a large number of structural and functional peripheral vascular and cardiac abnormalities to experience demand myocardial ischaemia. Transient myocardial ischaemia may lead to left ventricular (LV) dysfunction that can persist after the return of normal perfusion. This prolonged dysfunction is known as myocardial stunning. Repetitive episodes of ischaemia can be cumulative and have been shown to lead to prolonged LV dysfunction (in patients with ischaemic heart disease). Conventional HD itself is a sufficient cardiovascular functional stressor to precipitate such recurrent ischaemic insults, leading to myocardial functional and structural changes, eventually resulting in fixed systolic dysfunction and heart failure (conferring a dismal prognosis for patients undergoing dialysis). Furthermore these same haemodynamic insults may also adversely affect other vascular beds in other vulnerable organ systems, driving an even wider range of pathophysiological processes. A variety of therapeutic manoeuvres aimed at improving the haemodynamic tolerability of treatment have been shown to reduce acute dialysis-induced myocardial ischaemia. This article aims to give an appreciation of the possibility that modification of the dialysis treatment to improve tolerability of therapy may have the potential to provide us with additional therapeutic targets, to reduce currently excessive rates of cardiovascular morbidity and mortality. PMID:20093813

McIntyre, Chris W

2010-01-01

224

Oral Transmissibility of Prion Disease Is Enhanced by Binding to Soil Particles  

PubMed Central

Soil may serve as an environmental reservoir for prion infectivity and contribute to the horizontal transmission of prion diseases (transmissible spongiform encephalopathies [TSEs]) of sheep, deer, and elk. TSE infectivity can persist in soil for years, and we previously demonstrated that the disease-associated form of the prion protein binds to soil particles and prions adsorbed to the common soil mineral montmorillonite (Mte) retain infectivity following intracerebral inoculation. Here, we assess the oral infectivity of Mte- and soil-bound prions. We establish that prions bound to Mte are orally bioavailable, and that, unexpectedly, binding to Mte significantly enhances disease penetrance and reduces the incubation period relative to unbound agent. Cox proportional hazards modeling revealed that across the doses of TSE agent tested, Mte increased the effective infectious titer by a factor of 680 relative to unbound agent. Oral exposure to Mte-associated prions led to TSE development in experimental animals even at doses too low to produce clinical symptoms in the absence of the mineral. We tested the oral infectivity of prions bound to three whole soils differing in texture, mineralogy, and organic carbon content and found soil-bound prions to be orally infectious. Two of the three soils increased oral transmission of disease, and the infectivity of agent bound to the third organic carbon-rich soil was equivalent to that of unbound agent. Enhanced transmissibility of soil-bound prions may explain the environmental spread of some TSEs despite the presumably low levels shed into the environment. Association of prions with inorganic microparticles represents a novel means by which their oral transmission is enhanced relative to unbound agent. PMID:17616973

Johnson, Christopher J; Pedersen, Joel A; Chappell, Rick J; McKenzie, Debbie; Aiken, Judd M

2007-01-01

225

Nuclear factor-? B inducing kinase is required for graft-versus-host disease  

PubMed Central

Background Donor T lymphocytes are directly responsible for graft-versus-host disease. Molecules important in T-cell function may, therefore, be appropriate targets for graft-versus-host disease therapy and/or prophylaxis. Here we analyzed whether nuclear factor-? B inducing kinase might have a role in graft-versus-host disease. Design and Methods We studied the expression of nuclear factor-? B inducing kinase in human samples from patients with graft-versus-host disease. We also explored the effect of nuclear factor-? B inducing kinase in a murine model of graft-versus-host disease using donor cells from aly/aly mice (deficient in nuclear factor-? B inducing kinase) and C57BL/6 mice (control). Results We detected expression of nuclear factor-? B inducing kinase in T-lymphocytes in the pathological lesions of patients with acute graft-versus-host disease. Mice transplanted with aly/aly T lymphocytes did not develop graft-versus-host disease at all, while mice receiving C57BL/6 cells died of a lethal form of the disease. Deficiency of nuclear factor-? B inducing kinase did not affect the engrafting ability of donor T cells, but severely impaired their expansion capacity early after transplantation, and aly/aly T cells showed a higher proportion of apoptosis than did C57BL/6 T cells. Effector T lymphocytes were the T-cell subset most affected by nuclear factor-? B inducing kinase deficiency. We also detected lower amounts of inflammatory cytokines in the serum of mice receiving aly/aly T cells than in the serum of mice receiving C57BL/6 T cells. Conclusions Our results show that nuclear factor-? B inducing kinase has a role in graft-versus-host disease by maintaining the viability of activated alloreactive T lymphocytes. PMID:20823135

Sanchez-Valdepenas, Carmen; Casanova, Lucia; Colmenero, Isabel; Arriero, Mar; Gonzalez, Africa; Lozano, Nieves; Gonzalez-Vicent, Marta; Diaz, Miguel A.; Madero, Luis; Fresno, Manuel; Ramirez, Manuel

2010-01-01

226

Protein Kinase C-? Mediates Lung Injury Induced by Diesel Exhaust Particles  

PubMed Central

Recently, we reported that diesel exhaust particles (DEPs) disrupt tight junctions (TJs) in alveolar epithelial cells (AECs) via an increase in reactive oxygen species (ROS). In this study, we investigated the role of protein kinase C (PKC)–? activation in DEP-induced lung injury. C57/bl6 mice were instilled intratracheally with 50 ?l of saline containing 100 ?g of DEPs or titanium dioxide (TiO2). Twenty-four hours later, bronchoalveolar lavage was performed to assess neutrophil counts and protein concentrations. In addition, in vitro experiments were performed in primary rat and human AECs exposed to DEPs (50 ?g/cm2) for 3 hours. Transepithelial electrical conductance was measured, and TJ protein association was analyzed by immunoprecipitation. To determine whether the overexpression of antioxidants prevented DEP-induced lung injury, AECs and mice were infected with adenoviruses containing catalase and manganese superoxide dismutase (MnSOD) plasmids. In vivo, the overexpression of catalase and MnSOD prevented DEP-induced neutrophil recruitment. The inhibition of PKC-? activation also prevented DEP-induced neutrophil recruitment in vivo. In vitro, DEPs activated PKC-? in AECs, but not in alveolar macrophages. Using a specific myristolated PKC-? pseudosubstrate pepetide (PKC-? ps), we showed that PKC-? mediated the DEP-induced dissociation of occludin and zonula occludin–1 (ZO1) in rat and human AECs. In addition, the overexpression of constitutively active PKC-? induced the dissociation of occludin and ZO1 in AECs. DEP-induced TJ disruption occurs via PKC-?. TJ disruption seems to be in part responsible for DEP-induced lung injury. PMID:23221045

Caraballo, Juan C.; Borcherding, Jennifer; Thorne, Peter S.

2013-01-01

227

Near-infrared-induced heating of confined water in polymeric particles for efficient payload release.  

PubMed

Near-infrared (NIR) light-triggered release from polymeric capsules could make a major impact on biological research by enabling remote and spatiotemporal control over the release of encapsulated cargo. The few existing mechanisms for NIR-triggered release have not been widely applied because they require custom synthesis of designer polymers, high-powered lasers to drive inefficient two-photon processes, and/or coencapsulation of bulky inorganic particles. In search of a simpler mechanism, we found that exposure to laser light resonant with the vibrational absorption of water (980 nm) in the NIR region can induce release of payloads encapsulated in particles made from inherently non-photo-responsive polymers. We hypothesize that confined water pockets present in hydrated polymer particles absorb electromagnetic energy and transfer it to the polymer matrix, inducing a thermal phase change. In this study, we show that this simple and highly universal strategy enables instantaneous and controlled release of payloads in aqueous environments as well as in living cells using both pulsed and continuous wavelength lasers without significant heating of the surrounding aqueous solution. PMID:24717072

Viger, Mathieu L; Sheng, Wangzhong; Doré, Kim; Alhasan, Ali H; Carling, Carl-Johan; Lux, Jacques; de Gracia Lux, Caroline; Grossman, Madeleine; Malinow, Roberto; Almutairi, Adah

2014-05-27

228

Is delayed genomic instability specifically induced by high-LET particles?  

NASA Astrophysics Data System (ADS)

Ionizing radiation can induce a large variety of damages in the DNA. The processing or repair of this damage occurs in the first minutes up to several hours after irradiation. Afterwhile the remaining lesions are fixed in an irreparable state. However, in recent years, data have accumulated to suggest that genomic instability can manifest in the progeny of irradiated cells leading to accumulation of damage through cell generations. Different biological endpoints were described: delayed cell death, delayed mutations, de novo chromosomal instability. The question regarding the ability of sparsely ionizing X-or ?-rays to induce such phenomenon is still unclear for normal cells. In most of the reports, high linear energy transfer (LET) particles are able to induce genomic instability but not low-LET particles. The mechanisms underlying this phenomenon are still unknown. In human fibroblasts irradiated by heavy ions in a large range of LETs, we showed that the chromosomal instability is characterized by telomeric associations (TAS) involving specific chromosomes. The same instability is observed during the senescence process and during the first passages after viral transfection. The specific chromosomal instability that we observed after irradiation would not be a direct consequence of irradiation but would be a natural phenomenon occurring after many cell divisions. The effect of the irradiation would lie on the bypass of the senescence process that would permit cells with end to end fusions to survive and be transmitted through cell generations, accumulating chromosome rearrangements and chromosome imbalances. Research on molecular mechanisms of chromosomal instability is focused on the role of telomeres in end to end fusions. Such observations could contribute to understand why chromosomal instability is not a dose dependant phenomenon. Why high-LET particles would be so potent in inducing delayed instability? The answer might lie in the study of primary effects of ionizing radiations (X-rays, ?-rays and heavy ions). Cell survival studies showed that K-shell ionizations could be the primary physical events responsible of cell death. The quality of the DNA damages and gene mutations high-LET induced could be the keyhole leading to the great efficiency of these particles.

Testard, Isabelle; Sabatier, Laure

1998-12-01

229

Hypoxia and Hypoxia-Inducible Factor in Renal Disease  

Microsoft Academic Search

Tissue hypoxia occurs when local metabolism is disturbed by an imbalance between oxygen supply and consumption. In patients with chronic kidney disease, chronic hypoxia in the kidneys is the end result of multiple processes and mechanisms. Once established, however, accumulating evidence points to this chronic hypoxia as the central player and final common pathway to end-stage renal disease. The cellular

Masaomi Nangaku; Reiko Inagi; Toshio Miyata; Toshiro Fujita

2008-01-01

230

ORIGINAL ARTICLE Evidence that disease-induced population decline  

E-print Network

, Australia; 2 Institute for Antarctic and Southern Ocean Studies, University of Tasmania, Hobart, Tasmania of Zoology, University of Tasmania, Hobart, Tasmania, Australia Infectious disease has been shown the east coast of Tasmania. We observed a significant increase in inbreed- ing (FIS pre/post-disease Ã?0

Storfer, Andrew

231

Environmentally Induced Epigenetic Transgenerational Inheritance of Ovarian Disease  

Microsoft Academic Search

The actions of environmental toxicants and relevant mixtures in promoting the epigenetic transgenerational inheritance of ovarian disease was investigated with the use of a fungicide, a pesticide mixture, a plastic mixture, dioxin and a hydrocarbon mixture. After transient exposure of an F0 gestating female rat during embryonic gonadal sex determination, the F1 and F3 generation progeny adult onset ovarian disease

Eric Nilsson; Ginger Larsen; Mohan Manikkam; Carlos Guerrero-Bosagna; Marina I. Savenkova; Michael K. Skinner

2012-01-01

232

Particle Generation by Pulsed Excimer Laser Ablation in Liquid: Hollow Structures and Laser-Induced Reactions  

NASA Astrophysics Data System (ADS)

Pulsed laser ablation of solid targets in liquid media is a powerful method to fabricate micro-/nanoparticles, which has attracted much interest in the past decade. It represents a combinatorial library of constituents and interactions, and one can explore disparate regions of parameter space with outcomes that are impossible to envision a priori. In this work, a pulsed excimer laser (wavelength 248 nm, pulse width 30 ns) has been used to ablate targets in liquid media with varying laser fluences, frequencies, ablation times and surfactants. It is observed that hollow particles could be fabricated by excimer laser ablation of Al, Pt, Zn, Mg, Ag, Si, TiO2, and Nb2O5 in water or aqueous solutions. The hollow particles, with sizes from tens of nanometers to micrometers, may have smooth and continuous shells or have morphologies demonstrating that they were assembled from nanoparticles. A new mechanism has been proposed to explain the formation of these novel particle geometries. They were formed on laser-produced bubbles through bubble interface pinning by laser-produced solid species. Considering the bubble dynamics, thermodynamic and kinetic requirements have been discussed in the mechanism that can explain some phenomena associated with the formation of hollow particles, especially (1) larger particles are more likely to be hollow particles; (2) Mg and Al targets have stronger tendency to generate hollow particles; and (3) the 248 nm excimer laser is more beneficial to fabricate hollow particles in water than other lasers with longer wavelengths. The work has also demonstrated the possiblities to fabricate novel nanostructures through laser-induced reactions. Zn(OH)2/dodecyl sulfate flower-like nanostructures, AgCl cubes, and Ag2O cubes, pyramids, triangular plates, pentagonal rods and bars have been obtained via reactions between laser-produced species with water, electrolyes, or surfactant molecules. The underlying mechanisms of forming these structures have been discussed. The experimental results and the associated mechanisms developed in my research, and described in this thesis, have enriched the current understanding of particle generation by pulsed laser ablation in liquid. In so doing, my research has expanded the mechanistic routes for novel, or designer, nanoparticle geometries. Within the combinatorial and non-equilibrium environment provided by the unique experimental arrangement, the basic laws of material science still apply. Understanding and utilizing the laws will help researchers to fabricate new nanostructures by this and other methods providing similar environment.

Yan, Zijie

233

Particle disease: Biologic mechanisms of periprosthetic osteolysis in total hip arthroplasty  

PubMed Central

Numerous studies provide detailed insight into the triggering and amplification mechanisms of the inflammatory response associated with prosthetic wear particles, promoting final dominance of bone resorption over bone formation in multiple bone multicellular units around an implant. In fact, inflammation is a highly regulated process tightly linked to simultaneous stimulation of tissue protective and regenerative mechanisms in order to prevent collateral damage of periprosthetic tissues. A variety of cytokines, chemokines, hormones and specific cell populations, including macrophages, dendritic and stem cells, attempt to balance tissue architecture and minimize inflammation. Based on this fact, we postulate that the local tissue homeostatic mechanisms more effectively regulate the pro-inflammatory/pro-osteolytic cells/pathways in patients with none/mild periprosthetic osteolysis (PPOL) than in patients with severe PPOL. In this line of thinking, ‘particle disease theory’ can be understood, at least partially, in terms of the failure of local tissue homeostatic mechanisms. As a result, we envision focusing current research on homeostatic mechanisms in addition to traditional efforts to elucidate details of pro-inflammatory/pro-osteolytic pathways. We believe this approach could open new avenues for research and potential therapeutic strategies. PMID:22751380

Gallo, Jiri; Goodman, Stuart B; Konttinen, Yrjo T; Raska, Milan

2013-01-01

234

Assembly and biological and immunological properties of Newcastle disease virus-like particles.  

PubMed

Virus-like particles (VLPs) released from avian cells expressing the Newcastle disease virus (NDV) strain AV proteins NP, M, HN (hemagglutinin-neuraminidase), and F were characterized. The VLP-associated HN and F glycoproteins directed the attachment of VLPs to cell surfaces and fusion of VLP membranes with red blood cell membranes, indicating that they were assembled into VLPs in an authentic conformation. These particles were quantitatively prepared and used as an immunogen, without adjuvant, in BALB/c mice. The resulting immune responses, detected by enzyme-linked immunosorbent assay (ELISA), virus neutralization, and intracellular cytokine staining, were comparable to the responses to equivalent amounts of inactivated NDV vaccine virus. HN and F proteins from another strain of NDV, strain B1, could be incorporated into these VLPs. Foreign peptides were incorporated into these VLPs when fused to the NP or HN protein. The ectodomain of a foreign glycoprotein, the Nipah virus G protein, fused to the NDV HN protein cytoplasmic and transmembrane domains was incorporated into ND VLPs. Thus, ND VLPs are a potential NDV vaccine candidate. They may also serve as a platform to construct vaccines for other pathogens. PMID:20181713

McGinnes, Lori W; Pantua, Homer; Laliberte, Jason P; Gravel, Kathryn A; Jain, Surbhi; Morrison, Trudy G

2010-05-01

235

Pre-saddle neutron multiplicity for fission reactions induced by heavy ions and light particles  

E-print Network

Pre-saddle neutron multiplicity has been calculated for several fission reactions induced by heavy ions and light particles. Experimentally, it is impossible to determine the contribution of neutrons being emitted before the saddle point and those emitted between the saddle and the scission points. Determination of the pre-saddle neutron multiplicity in our research is based on the comparison between the experimental anisotropies and those predicted by the standard saddle-point statistical model. Analysis of the results shows that the pre-saddle neutron multiplicity depends on the fission barrier height and stability of the compound nucleus. In heavy ion induced fission, the number of pre-saddle neutrons decreases with increasing the excitation energy of the compound nucleus. A main cause of this behavior is due to a reduction in the ground state-to-saddle point transition time with increasing the excitation energy of the compound nucleus. Whereas in induced fission by light particles, the number of pre-saddle neutrons increases with increasing the excitation energy of the compound nucleus.

S. Soheyli; M. K. Khalili

2013-06-03

236

APS/123-QED A Theory for Particle Settling and Shear-Induced Migration in Thin Film Flow  

E-print Network

APS/123-QED A Theory for Particle Settling and Shear-Induced Migration in Thin Film Flow Benjamin P the film depth, unlike Zhou et al.'s model. Average velocities for the liquid and particulate phases by the relative motion of the liquid and particulate phases. At FIG. 1: Particle-rich ridge in an inclined film

Soatto, Stefano

237

What is Alzheimer's Disease? Alzheimer's disease is a form of brain degeneration in which abnormal particles called neurofibrillary  

E-print Network

What is Alzheimer's Disease? Alzheimer's disease is a form of brain degeneration in which abnormal fact and remember it 30 minutes, or a day later, a skill we refer to as "memory". Who Gets Alzheimer's disease? The two main categories of Alzheimer's disease (AD) are familial and sporadic. Familial Alzheimer

Contractor, Anis

238

Bragg scattering and Brownian motion dynamics in optically induced crystals of submicron particles  

NASA Astrophysics Data System (ADS)

A set of four confocal laser beams of 1064-nm wavelength is used to prepare optically induced crystals of submicron particles in aqueous solution. Thousands of polystyrene spheres of about 200 nm in diameter are trapped in three dimensions. Bragg scattering patterns obtained with a probe beam of 532-nm wavelength are in agreement with the calculated lattice structure and its polarization dependence. The decay and rise of the Bragg scattering intensity upon switching the lattice off and on reveal the Brownian motion dynamics of the particles in the periodic optical trapping potential. Experimental results agree well with results from trajectory simulations based on the Langevin equation. The results exhibit the interplay between Brownian motion and deterministic forces in an inhomogeneous (near-)periodic optical trapping potential.

Sapiro, R. E.; Slama, B. N.; Raithel, G.

2013-05-01

239

Bragg scattering and Brownian motion dynamics in optically induced crystals of submicron particles.  

PubMed

A set of four confocal laser beams of 1064-nm wavelength is used to prepare optically induced crystals of submicron particles in aqueous solution. Thousands of polystyrene spheres of about 200 nm in diameter are trapped in three dimensions. Bragg scattering patterns obtained with a probe beam of 532-nm wavelength are in agreement with the calculated lattice structure and its polarization dependence. The decay and rise of the Bragg scattering intensity upon switching the lattice off and on reveal the Brownian motion dynamics of the particles in the periodic optical trapping potential. Experimental results agree well with results from trajectory simulations based on the Langevin equation. The results exhibit the interplay between Brownian motion and deterministic forces in an inhomogeneous (near-)periodic optical trapping potential. PMID:23767544

Sapiro, R E; Slama, B N; Raithel, G

2013-05-01

240

Long-term changes in amphetamine-induced reinforcement and aversion in rats following exposure to 56Fe particle  

NASA Technical Reports Server (NTRS)

Exposing rats to heavy particles produces alterations in the functioning of dopaminergic neurons and in the behaviors that depend upon the integrity of the dopaminergic system. Two of these dopamine-dependent behaviors include amphetamine-induced reinforcement, measure using the conditioned place preference procedure, and amphetamine-induced reinforcement, measured using the conditioned place preference procedure, and amphetamine-induced aversion, measured using the conditioned taste aversion. Previous research has shown that exposing rats to 1.0 Gy of 1GeV/n 56Fe particles produced a disruption of an amphetamine-induced taste aversion 3 days following exposure, but produced an apparent enhancement of the aversion 112 days following exposure. The present experiments were designed to provide a further evaluation of these results by examining taste aversion learning 154 days following exposure to 1.0 Gy 56Fe particles and to establish the convergent validity of the taste aversion results by looking at the effects of exposure on the establishment of an amphetamine-induced conditioned place preference 3, 7, and 16 weeks following irradiation. The taste aversion results failed to confirm the apparent enhancement of the amphetamine-induced CTA observed in the prior experiment. However, exposure to 56Fe particles prevented the acquisition of amphetamine-induced place preference at all three-time intervals. The results are interpreted as indicating that exposure to heavy particles can produce long-term changes in behavioral functioning. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.

2003-01-01

241

Preventing diet induced disease: bioavailable nutrient-rich, low-  

E-print Network

.g. malnutrition, typhoid fever and polio. Currently many of the chronic diseases epidemic in human populations to look beyond the status quo e.g. medical efforts focusing more on treatments for older people than

Paris-Sud XI, Université de

242

Human alkaloid biosynthesis : chemical inducers of Parkinson's disease?  

E-print Network

The occurrence of certain alkaloids in the human brain appears to be associated with the onset of Parkinson's disease (PD). Recently, a human protein bearing homology to an alkaloid synthase in plants was identified. This ...

Hatzios, Stavroula K. (Stavroula-Artemis K.)

2005-01-01

243

Analytical Applications Of Particle-Induced X-Ray Emission (PIXE)  

NASA Astrophysics Data System (ADS)

In this paper a complex study of the capabilities of Particle-Induced X-ray Emission (PIXE) technique for the determination of major, minor and trace constituents of metallurgical, biological and environmental samples has been done. The elements identified in the metallurgical samples (steels) using PIXE were: K, Ca, V, Cr, Mn, Fe, Co, Cu, Ni, Zn, W, Ga, As, Pb, Mo, Rb, In, Rh, Zr, Pd, Nb, Sn and Sb. In the investigated biological and environmental samples (vegetals leaves, soil and mosses) PIXE analysis allowed determination of: S, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, As, Hg and Pb.

Popescu, I. V.; Ene, A.; Stihi, C.; Bancuta, A.; Dima, G.; Badica, T.; Ghisa, V.

2007-04-01

244

Methotrexate-induced pneumonitis in a patient with Crohn's disease  

Microsoft Academic Search

Pulmonary toxicity is a well recognised but infrequent adverse event of treatment with methotrexate. The vast majority of cases have occurred in patients with rheumatoid arthritis; here we present the case of a 44-year old woman with ileo-colonic Crohn's disease who developed methotrexate pneumonitis. The patient had a 10year history of Crohn's disease and, in the last 18months, she was

Giovanna Margagnoni; Valeria Papi; Annalisa Aratari; Luca Triolo; Claudio Papi

2010-01-01

245

Cellular therapy and induced neuronal replacement for Huntington's disease.  

PubMed

Huntington's disease (HD) is an inherited, relentlessly progressive neurodegenerative disease with an invariably fatal outcome. HD is inherited in an autosomal dominant fashion, and is characterized pathologically by the loss of cortical and striatal neurons, and clinically by involuntary choreiform movements accompanied by progressive cognitive impairment and emotional lability. The disorder is caused by an expanded cystosine adenine guanine (CAG) tri-nucleotide repeat encoding polyglutamine (polyQ) in the first exon of the Huntingtin gene. There is a correlation between the number of CAG repeats and disease onset, such that in patients with CAG repeat lengths of 36 to 60, disease symptoms typically manifest after 35 years of age, whereas CAG repeat lengths >60 yield the more severe juvenile form of the disease. Even though mutant huntingtin is expressed throughout the brain, it is characterized by the selective degeneration of medium spiny neurons of the caudate and putamen, which heralds more widespread neuronal degeneration with disease progression. The mechanisms of cell dysfunction and death in HD have been the subjects of a number of studies, which have led to therapeutic strategies largely based on the amelioration of mutant huntingtin-related metabolic impairment and cellular toxicity. Each of these approaches has aimed to delay or stop the preferential degeneration of medium spiny neurons early in the disease course. Yet, in later stages of the disease, after cell death has become prominent, cell replacement therapy (whether by direct cell transplantation or by the mobilization of endogenous progenitors) may comprise a stronger potential avenue for therapy. In this review, we will consider recent progress in the transplantation of fetal striatal cells to the HD brain, as well as emerging alternative sources for human striatal progenitor cells. We will then consider the potential application of gene therapy toward the induction of striatal neurogenesis and neuronal recruitment, with an eye toward its potential therapeutic use in HD. PMID:21971961

Benraiss, Abdellatif; Goldman, Steven A

2011-10-01

246

Multielement analysis of biological materials by particle-induced X-ray emission (PIXE)  

SciTech Connect

An analytical particle-induced X-ray emission (PIXE) procedure for the multielement analysis of biological materials consists of various stages. These include sample and specimen preparation, specimen bombardment, spectral data processing, quantification and correction for matrix effects. Critical aspects of the procedure are contamination and/or losses during sample and specimen preparation and the danger of radiation or heat-induced losses during specimen bombardment. With optimized PIXE procedures precisions of 1-2% and an accuracy of better than 5% are obtainable, whereas the detection limits are down to 0.1 microgram/g. Because of its inherent characteristics, PIXE offers great potential for trace element analysis in the biological and medical fields, and this is demonstrated through selected examples of applications.121 references.

Maenhaut, W. (Instituut voor Nucleaire Wetenschappen, Rijksuniversiteit Gent (Belgium))

1990-03-01

247

Newcastle disease virus-induced cytopathic effect in infected cells is caused by apoptosis  

Microsoft Academic Search

The velogenic Newcastle disease virus (NDV) causes highly infectious and economically significant Newcastle disease (ND) in birds of various species. In cell culture NDV induces cytopathic effect (CPE) characterized by rounding, vacuolation, syncytia formation and cell death. Aside from cell to cell fusion caused by the F and HN glycoprotein of the virus molecular events leading to cell death are

P. V. Ravindra; Ashok K. Tiwari; Barkha Ratta; Uttara Chaturvedi; Sudesh Kumar Palia; R. S. Chauhan

2009-01-01

248

Examination of Susceptibility to Libby Amphibole Asbestos-Induced Injury in Rat Models of Cardiovascular Disease  

EPA Science Inventory

Although cardiovascular disease (CVD) is considered a risk factor for the exacerbation of air pollution health effects, no studies have been done assessing the influence of the disease on the development of lung injury induced by asbestos exposure. In this study we examined lung ...

249

MIF induces osteoclast differentiation and contributes to progression of periodontal disease in mice  

Microsoft Academic Search

Periodontal disease (PD) is a chronic inflammatory and alveolar bone destructive disease triggered by microorganisms from the oral biofilm. Oral inoculation of mice with the periodontopathogen Aggregatibacter actinomycetemcomitans (Aa) induces marked alveolar bone loss and local production of inflammatory mediators, including Macrophage Migration Inhibitory Factor (MIF). The role of MIF for alveolar bone resorption during PD is not known. In

Mila Fernandes Moreira Madeira; Celso Martins Queiroz-Junior; Graciela Mitre Costa; Patrícia Campi Santos; Elcia Maria Silveira; Gustavo Pompermaier Garlet; Patrícia Silva Cisalpino; Mauro Martins Teixeira; Tarcília Aparecida Silva; Daniele da Glória Souza

250

Fluorescent Light-Induced Chromatid Breaks Distinguish Alzheimer Disease Cells from Normal Cells in Tissue Culture  

Microsoft Academic Search

The neurodegeneration and amyloid deposition of sporadic Alzheimer disease (AD) also occur in familial AD and in all trisomy-21 Down syndrome (DS) patients, suggesting a common pathogenetic mechanism. We investigated whether defective processing of damaged DNA might be that mechanism, as postulated for the neurodegeneration in xeroderma pigmentosum, a disease with defective repair not only of UV radiation-induced, but also

Ram Parshad; Katherine K. Sanford; Floyd M. Price; Lynn K. Melnick; Linda E. Nee; Mark B. Schapiro; Robert E. Tarone; Jay H. Robbins

1996-01-01

251

Effect of electric-field-induced capillary attraction on the motion of particles at an oil-water interface.  

PubMed

Here, we investigate experimentally and theoretically the motion of spherical glass particles of radii 240-310 microm attached to a tetradecane-water interface. Pairs of particles, which are moving toward each other under the action of lateral capillary force, are observed by optical microscopy. The purpose is to check whether the particle electric charges influence the particle motion, and whether an electric-field-induced capillary attraction could be detected. The particles have been hydrophobized by using two different procedures, which allow one to prepare charged and uncharged particles. To quantify the hydrodynamic viscous effects, we developed a semiempirical quantitative approach, whose validity was verified by control experiments with uncharged particles. An appropriate trajectory function was defined, which should increase linearly with time if the particle motion is driven solely by the gravity-induced capillary force. The analysis of the experimental results evidences for the existence of an additional attraction between two like-charged particles at the oil-water interface. This attraction exceeds the direct electrostatic repulsion between the two particles and leads to a noticeable acceleration of their motion. PMID:18060167

Boneva, Mariana P; Christov, Nikolay C; Danov, Krassimir D; Kralchevsky, Peter A

2007-12-28

252

Chemical characterization of single micro- and nano-particles by optical catapulting-optical trapping-laser-induced breakdown spectroscopy  

NASA Astrophysics Data System (ADS)

Spectral identification of individual micro- and nano-sized particles by the sequential intervention of optical catapulting, optical trapping and laser-induced breakdown spectroscopy is presented. The three techniques are used for different purposes. Optical catapulting (OC) serves to put the particulate material under inspection in aerosol form. Optical trapping (OT) permits the isolation and manipulation of individual particles from the aerosol, which are subsequently analyzed by laser-induced breakdown spectroscopy (LIBS). Once catapulted, the dynamics of particle trapping depends both on the laser beam characteristics (power and intensity gradient) and on the particle properties (size, mass and shape). Particles are stably trapped in air at atmospheric pressure and can be conveniently manipulated for a precise positioning for LIBS analysis. The spectra acquired from the individually trapped particles permit a straightforward identification of the material inspected. Variability of LIBS signal for the inspection of Ni microspheres was 30% relative standard deviation. OC-OT-LIBS permits the separation of particles in a heterogeneous mixture and the subsequent analysis of the isolated particle of interest. In order to evaluate the sensitivity of the approach, the number of absolute photons emitted by a single trapped particle was calculated. The limit of detection (LOD) for Al2O3 particles was calculated to be 200 attograms aluminium.

Fortes, Francisco J.; Fernández-Bravo, Angel; Javier Laserna, J.

2014-10-01

253

Gluten induces an intestinal cytokine response strongly dominated by interferon gamma in patients with celiac disease  

Microsoft Academic Search

Background & Aims: Celiac disease appears to be a T cell–mediated enteropathy induced by gluten in genetically predisposed individuals. Duodenal biopsy specimens from patients with celiac disease and histologically normal controls were investigated to see if cytokine expression is related to disease activity. Methods: Cytokine messenger RNA (mRNA) expression was determined by quantitative reverse-transcription polymerase chain reaction and in situ

Ellen M. Nilsen; Frode L. Jahnsen; Knut E. A. Lundin; Olav Fausa; Ludvig M. Sollid; Jørgen Jahnsen; Helge Scott; Per Brandtzaeg

1998-01-01

254

particles  

NASA Astrophysics Data System (ADS)

We explore a facile and nontoxic hydrothermal route for synthesis of a Cu2ZnSnS4 nanocrystalline material by using l-cysteine as the sulfur source and ethylenediaminetetraacetic acid (EDTA) as the complexing agent. The effects of the amount of EDTA, the mole ratio of the three metal ions, and the hydrothermal temperature and time on the phase composition of the obtained product have been systematically investigated. The addition of EDTA and an excessive dose of ZnCl2 in the hydrothermal reaction system favor the generation of kesterite Cu2ZnSnS4. Pure kesterite Cu2ZnSnS4 has been synthesized at 180°C for 12 h from the reaction system containing 2 mmol of EDTA at 2:2:1 of Cu/Zn/Sn. It is confirmed by Raman spectroscopy that those binary and ternary phases are absent in the kesterite Cu2ZnSnS4 product. The kesterite Cu2ZnSnS4 material synthesized by the hydrothermal process consists of flower-like particles with 250 to 400 nm in size. It is revealed that the flower-like particles are assembled from single-crystal Cu2ZnSnS4 nanoflakes with ca. 20 nm in size. The band gap of the Cu2ZnSnS4 nanocrystalline material is estimated to be 1.55 eV. The films fabricated from the hierarchical Cu2ZnSnS4 particles exhibit fast photocurrent responses under intermittent visible-light irradiation, implying that they show potentials for use in solar cells and photocatalysis.

Xia, Yu; Chen, Zhihong; Zhang, Zhengguo; Fang, Xiaoming; Liang, Guozheng

2014-05-01

255

Current-induced transition from particle-by-particle to concurrent intercalation in phase-separating battery electrodes.  

PubMed

Many battery electrodes contain ensembles of nanoparticles that phase-separate on (de)intercalation. In such electrodes, the fraction of actively intercalating particles directly impacts cycle life: a vanishing population concentrates the current in a small number of particles, leading to current hotspots. Reports of the active particle population in the phase-separating electrode lithium iron phosphate (LiFePO4; LFP) vary widely, ranging from near 0% (particle-by-particle) to 100% (concurrent intercalation). Using synchrotron-based X-ray microscopy, we probed the individual state-of-charge for over 3,000 LFP particles. We observed that the active population depends strongly on the cycling current, exhibiting particle-by-particle-like behaviour at low rates and increasingly concurrent behaviour at high rates, consistent with our phase-field porous electrode simulations. Contrary to intuition, the current density, or current per active internal surface area, is nearly invariant with the global electrode cycling rate. Rather, the electrode accommodates higher current by increasing the active particle population. This behaviour results from thermodynamic transformation barriers in LFP, and such a phenomenon probably extends to other phase-separating battery materials. We propose that modifying the transformation barrier and exchange current density can increase the active population and thus the current homogeneity. This could introduce new paradigms to enhance the cycle life of phase-separating battery electrodes. PMID:25218062

Li, Yiyang; El Gabaly, Farid; Ferguson, Todd R; Smith, Raymond B; Bartelt, Norman C; Sugar, Joshua D; Fenton, Kyle R; Cogswell, Daniel A; Kilcoyne, A L David; Tyliszczak, Tolek; Bazant, Martin Z; Chueh, William C

2014-12-01

256

Attraction between particles at a liquid interface due to the interplay of gravity- and electric-field-induced interfacial deformations.  

PubMed

In a previous study, we established that the attraction between electrically charged particles attached to a water/tetradecane interface is stronger than predicted on the basis of the gravity-induced lateral capillary force. Here, our goal is to explain this effect. The investigated particles are hydrophobized glass spheres of radii between 240 and 320 microm. Their weight is large enough to deform the liquid interface. The interfacial deformation is considerably greater for charged particles because of the electrodipping force that pushes the particles toward the water phase. By independent experiments with particles placed between two electrodes, we confirmed the presence of electric charges at the particle/tetradecane interface. The theoretical analysis shows that if the distribution of these surface charges is isotropic, the meniscus produced by the particle electric field decays too fast with distance and cannot explain the experimental observations. However, if the surface-charge distribution is anisotropic, it induces a saddle-shaped deformation in the liquid interface around each particle. This deformation, which is equivalent to a capillary quadrupole, decays relatively slow. Its interference with the gravity-induced isotropic meniscus around the other particle gives rise to a long-range attractive capillary force, F approximately 1/L3 (L=interparticle distance). The obtained agreement between the experimental and theoretical curves, and the reasonable values of the parameters determined from the fits, indicate that the observed stronger attraction in the investigated system can be really explained as a hybrid interaction between gravity-induced "capillary charges" and electric-field-induced "capillary quadrupoles". PMID:19719220

Boneva, Mariana P; Danov, Krassimir D; Christov, Nikolay C; Kralchevsky, Peter A

2009-08-18

257

Mineral particles of varying composition induce differential chemokine release from epithelial lung cells: importance of physico-chemical characteristics.  

PubMed

Presently, little is known about the potential health effects of mineral particles other than asbestos and quartz. In this study, a human epithelial lung cell line (A549), primary human small airway epithelial cells (SAECs) and primary rat type 2 (T2) cells were exposed to stone quarry particles of two size fractions (<10 and <2.5 microm) from nine different rock samples. The ability to induce the release of chemokines from lung cells was investigated and compared with the particles' mineral and element composition and the amount of soluble elements. The stone particles induced the release of only low levels of interleukin (IL)-8 from A549 cells. In contrast, some of the other particles induced the release of high levels of macrophage inflammatory protein (MIP)-2 from T2 cells, and high levels of IL-8 from SAECs. Differences in particle surface area could account for differences in activity between the <10 and <2.5 microm fractions of six out of the nine rock samples. For two samples the <2.5 microm fraction was most active and for one sample the <10 microm fraction was most active. Content of the mineral plagioclase displayed a strong, negative correlation with the potential to induce MIP-2, whereas the mineral pyroxene was positively correlated with MIP-2 induction. However, neither plagioclase nor pyroxene content was sufficient to explain differences in bioactivity between the particles. No statistically significant correlation was found between the amounts of total or soluble elements and MIP-2 release. In conclusion, the results suggest that mineral particles with a high content of plagioclase have a low potential to induce a pro-inflammatory response. However, a particular mineral or element responsible for eliciting strong increases in chemokine release could not be identified. Thus, at present it appears that analysing mineral and element content is insufficient to predict stone particle bioactivity, and that biological testing is a necessity. PMID:15640311

Ovrevik, J; Myran, T; Refsnes, M; Låg, M; Becher, R; Hetland, R B; Schwarze, P E

2005-04-01

258

Nimesulide Improves the Symptomatic and Disease Modifying Effects of Leflunomide in Collagen Induced Arthritis  

PubMed Central

Nimesulide is a COX-2 inhibitor used for symptomatic relief of rheumatoid arthritis. Leflunomide is an anti-pyrimidine used to manage the progression of rheumatoid arthritis. Herein we studied the influence of nimesulide and leflunomide combination in terms of disease symptoms and progression using collagen-induced arthritis model in mice, as a model for rheumatoid arthritis. Collagen induced arthritis was induced by immunization with type II collagen. Assessment of joint stiffness and articular hyperalgesia were evaluated using a locomotor activity cage and the Hargreaves method, respectively. Disease progression was assessed via arthritic index scoring, X-ray imaging, myeloperoxidase enzyme activity and histopathologic examination. Nimesulide induced only transient symptomatic alleviation on the top of decreased leucocytic infiltration compared to arthritis group. However, nimesulide alone failed to induce any significant improvement in the radiological or pathological disease progression. Leflunomide alone moderately alleviates the symptoms of arthritis and moderately retarded the radiological and pathological disease progression. Combination of nimesulide and leflunomide significantly improved symptomatic (analgesia and joint stiffness) and arthritic disease progression (radiological, pathological and Myeloperoxidase enzyme activity) in collagen induced arthritis animal model. PMID:25375820

Al-Abd, Ahmed M.; Al-Abbasi, Fahad A.; Nofal, Salwa M.; Khalifa, Amani E.; Williams, Richard O.; El-Eraky, Wafaa I.; Nagy, Ayman A.; Abdel-Naim, Ashraf B.

2014-01-01

259

Diesel exhaust particle-induced alterations of pulmonary phase I and phase II enzymes of rats.  

PubMed

Although diesel exhaust particles (DEP) are known to produce pulmonary disorders, the xenobiotic metabolic pathways associated with DEP detoxification and bioactivation remain unclear. In this study, the effect of acute exposure of DEP on phase I and phase II enzymes of rat lung was investigated. Intratracheal administration of DEP produced an induction of cytochrome P-450 (CYP) 1A1 enzyme protein and activity at 1 d postexposure, with the enzyme level returning to control at 5 d postexposure. On the other hand, carbon black (CB), a particle control, did not show any induction of CYP1A1 protein or enzyme activity. However, both DEP and CB significantly decreased CYP2B1 protein and enzyme activity at 1 d postexposure. The decrease in CYP2B1 enzyme protein and activity by DEP or CB treatment was observed up to 7 d postexposure. DEP and CB treatments also significantly attenuated glutathione S-transferase (GST)-pi protein at 1 d postexposure. Both DEP and CB at 35 mg/kg significantly decreased the activities of GST and catalase at 1 and 7 d postexposure. DEP, but not CB, significantly induced quinone reductase (QR) activity at 7 d postexposure. This study suggests that DEP may induce CYP1A1 and QR enzymes via a chemical effect, while the carbonaceous core may be involved in the attenuation of CYP2B1, GST, and catalase proteins and enzyme activities. PMID:12653020

Rengasamy, A; Barger, M W; Kane, E; Ma, J K H; Castranova, V; Ma, J Y C

2003-01-24

260

Targeted cytoplasmic irradiation with alpha particles induces mutations in mammalian cells  

PubMed Central

Ever since x-rays were shown to induce mutation in Drosophila more than 70 years ago, prevailing dogma considered the genotoxic effects of ionizing radiation, such as mutations and carcinogenesis, as being due mostly to direct damage to the nucleus. Although there was indication that alpha particle traversal through cellular cytoplasm was innocuous, the full impact remained unknown. The availability of the microbeam at the Radiological Research Accelerator Facility of Columbia University made it possible to target and irradiate the cytoplasm of individual cells in a highly localized spatial region. By using dual fluorochrome dyes (Hoechst and Nile Red) to locate nucleus and cellular cytoplasm, respectively, thereby avoiding inadvertent traversal of nuclei, we show here that cytoplasmic irradiation is mutagenic at the CD59 (S1) locus of human–hamster hybrid (AL) cells, while inflicting minimal cytotoxicity. The principal class of mutations induced are similar to those of spontaneous origin and are entirely different from those of nuclear irradiation. Furthermore, experiments with radical scavenger and inhibitor of intracellular glutathione indicated that the mutagenicity of cytoplasmic irradiation depends on generation of reactive oxygen species. These findings suggest that cytoplasm is an important target for genotoxic effects of ionizing radiation, particularly radon, the second leading cause of lung cancer in the United States. In addition, cytoplasmic traversal by alpha particles may be more dangerous than nuclear traversal, because the mutagenicity is accomplished by little or no killing of the target cells. PMID:10220401

Wu, Li-Jun; Randers-Pehrson, Gerhard; Xu, An; Waldren, Charles A.; Geard, Charles R.; Yu, ZengLiang; Hei, Tom K.

1999-01-01

261

HZE particle radiation induces tissue-specific and p53-dependent mutagenesis in transgenic animals  

NASA Technical Reports Server (NTRS)

Transgenic animals, with the integrated target gene, provide a unique approach for measuring and characterizing mutations in any tissue of the animal. We are using the plasmid-based lacZ transgenic mice with different p53 genetic background to examine radiation-induced genetic damage resulting from exposure to heavy particle radiation. We measured lacZ mutation frequencies (MF) in the brain and spleen tissues at various times after exposing animals to an acute dose of 1 Gy of 1GeV/amu iron particles. MF in the spleen of p53+/+ animals increased up to 2.6-fold above spontaneous levels at 8 weeks post irradiation. In contrast, brain MF from the same animals increased 1.7-fold above controls in the same period. In the p53-/- animals, brain MF increased to 2.2-fold above spontaneous levels at 1 week after treatment, but returned to control levels thereafter. Radiation also induced alterations in the spectrum of mutants in both tissues, accompanied by changes in the frequency of mutants with deletions extending past the transgene into mouse genomic DNA. Our results indicate that the accumulation of transgene MF after radiation exposure is dependant on the tissue examined as well as the p53 genetic background of the animals.

Chang, P. Y.; Kanazawa, N.; Lutze-Mann, L.; Winegar, R.

2001-01-01

262

Interaction of the human cytomegalovirus particle with the host cell induces hypoxia-inducible factor 1 alpha  

SciTech Connect

The cellular protein hypoxia-inducible factor 1 alpha (HIF-1{alpha}) was induced after infection of human fibroblasts with human cytomegalovirus (HCMV). HCMV irradiated with ultraviolet light (uv-HCMV) also elicited the effect, demonstrating that the response was provoked by interaction of the infecting virion with the cell and that viral gene expression was not required. Although induction of HIF-1{alpha} was initiated by an early event, accumulation of the protein was not detected until 9 hours post infection, with levels increasing thereafter. Infection with uv-HCMV resulted in increased abundance of HIF-1{alpha}-specific RNA, indicating stimulation of transcription. In addition, greater phosphorylation of the protein kinase Akt was observed, and the activity of this enzyme was required for induction of HIF-1{alpha} to occur. HIF-1{alpha} controls the expression of many cellular gene products; therefore the findings reveal new ways in which interaction of the HCMV particle with the host cell may cause significant alterations to cellular physiology.

McFarlane, Steven; Nicholl, Mary Jane; Sutherland, Jane S.; Preston, Chris M., E-mail: Christopher.preston@glasgow.ac.u

2011-05-25

263

Influence of 70 nm silica particles in mice with cisplatin or paraquat-induced toxicity.  

PubMed

In the pharmaceutical industry, nano-size materials are designed as drug carriers and diagnosis probes. Interactions between nano-size materials and chemicals need investigating. Here, we investigated whether nano-size materials affect chemical-induced toxicity using silica particles, which have been widely used in cosmetics and drug delivery and have diameters of 70 (SP70), 300 (SP300) and 1000 (SP1000) nm, a popular anti-tumor agent, cisplatin, and a widely used herbicide, paraquat. Mice were treated with either cisplatin (100 micromol/kg, intraperitoneally) or paraquat (50 mg/kg, intraperitoneally), with or without intravenous silica particle administration. All treatments were non-lethal and did not show severe toxicity, except for injection with both cisplatin and SP70, which were lethal. When mice received with paraquat and/or the silica particles, synergistic enhanced toxicity was observed in both paraquat- and SP70-treated mice. These synergic effects were not observed with either Si300 or 1000 treatment. Our findings suggest that further evaluation on the interaction between nano-size materials and chemicals is critical for the pharmaceutical application of nanotechnology. PMID:19618677

Nishimori, H; Kondoh, M; Isoda, K; Tsunoda, S; Tsutsumi, Y; Yagi, K

2009-06-01

264

Angular distribution in two-particle emission induced by neutrinos and electrons  

E-print Network

The angular distribution of the phase space arising in two-particle emission reactions induced by electrons and neutrinos is computed in the laboratory (Lab) system by boosting the isotropic distribution in the center of mass (CM) system used in Monte Carlo generators. The Lab distribution has a singularity for some angular values, coming from the Jacobian of the angular transformation between CM and Lab systems. We recover the formula we obtained in a previous calculation for the Lab angular distribution. This is in accordance with the Monte Carlo method used to generate two-particle events for neutrino scattering\\cite{Sob12}. Inversely, by performing the transformation to the CM system, it can be shown that the phase-space function, which is proportional to the two particle-two hole (2p-2h) hadronic tensor for a constant current operator, can be computed analytically in the frozen nucleon approximation, if Pauli blocking is absent. The results in the CM frame confirm our previous work done using an alternative approach in the Lab frame. The possibilities of using this method to compute the hadronic tensor by a boost to the CM system are analyzed.

I. Ruiz Simo; C. Albertus; J. E. Amaro; M. B. Barbaro; J. A. Caballero; T. W. Donnelly

2014-07-26

265

Angular distribution in two-particle emission induced by neutrinos and electrons  

E-print Network

The angular distribution of the phase space arising in two-particle emission reactions induced by electrons and neutrinos is computed in the laboratory (Lab) system by boosting the isotropic distribution in the center of mass (CM) system used in Monte Carlo generators. The Lab distribution has a singularity for some angular values, coming from the Jacobian of the angular transformation between CM and Lab systems. We recover the formula we obtained in a previous calculation for the Lab angular distribution. This is in accordance with the Monte Carlo method used to generate two-particle events for neutrino scattering~\\cite{Sob12}. Inversely, by performing the transformation to the CM system, it can be shown that the phase-space function, which is proportional to the two particle-two hole (2p-2h) hadronic tensor for a constant current operator, can be computed analytically in the frozen nucleon approximation, if Pauli blocking is absent. The results in the CM frame confirm our previous work done using an alterna...

Simo, I Ruiz; Amaro, J E; Barbaro, M B; Caballero, J A; Donnelly, T W

2014-01-01

266

Angular distribution in two-particle emission induced by neutrinos and electrons  

NASA Astrophysics Data System (ADS)

The angular distribution of the phase space arising in two-particle emission reactions induced by electrons and neutrinos is computed in the laboratory (Lab) system by boosting the isotropic distribution in the center of mass (CM) system used in Monte Carlo generators. The Lab distribution has a singularity for some angular values, coming from the Jacobian of the angular transformation between CM and Lab systems. We recover the formula we obtained in a previous calculation for the Lab angular distribution. This is in accordance with the Monte Carlo method used to generate two-particle events for neutrino scattering [J. T. Sobczyk, Phys. Rev. C 86, 015504 (2012)]. Inversely, by performing the transformation to the CM system, it can be shown that the phase-space function, which is proportional to the two-particle-two-hole (2p-2h) hadronic tensor for a constant current operator, can be computed analytically in the frozen nucleon approximation, if Pauli blocking is absent. The results in the CM frame confirm our previous work done using an alternative approach in the Lab frame. The possibilities of using this method to compute the hadronic tensor by a boost to the CM system are analyzed.

Simo, I. Ruiz; Albertus, C.; Amaro, J. E.; Barbaro, M. B.; Caballero, J. A.; Donnelly, T. W.

2014-09-01

267

The effect of flow geometry on shear-induced particle segregation and resuspension  

NASA Astrophysics Data System (ADS)

In this thesis, we investigate through theory and experiment the influence of the flow geometry on various shear-induced migration phenomena such as particle demixing, viscous resuspension and meniscus accumulation for a suspension of rigid, non-colloidal particles. The major focus of this thesis is the elucidation of a particle flux mechanism that has been ignored in the literature in the theoretical calculation of the concentration distribution in shear-induced migration phenomena. This mechanism is the convective flux due to the secondary currents arising from the non-Newtonian rheology of suspensions. Historically, suspensions have been modeled as Newtonian fluids with concentration dependent viscosities when calculating velocity distributions due to the tremendous simplification of the governing equations. The results presented in this thesis, however, demonstrate that it is critical to consider the complete rheology of a concentrated suspension when modeling flows in complex geometries. While the magnitude of the secondary currents is small, in many cases they are the dominant mechanism governing the resulting particle concentration distribution. In chapters 2 through 4, we investigate the impact of these secondary currents on the concentration profiles developed in suspension flow through conduits of arbitrary geometry, and in resuspension flow through a tube. In chapter 5, we examine the radial segregation of particles in the squeeze flow of concentrated suspensions. This flow is identical to that produced in loading suspensions on to a parallel plate viscometer and thus the concentration inhomogeneities generated during the loading phenomenon may play a role in the well known scatter of torque measurements in this system. We develop a criterion in terms of the experimental parameters in a parallel plate experiment for the onset of radial inhomogeneities. In the final investigation reported in this thesis, we develop a theoretical model for describing the droplet distribution in the Poiseuille flow of an emulsion through a tube. We show that the mathematical problem that results from this model is amenable to self-similar analysis via the trial function approach. The self-similar solution so obtained is used to evaluate oscillatory flows as a possible technique for separation of the dispersed phase from suspending fluid.

Ramachandran, Arun

268

Dopamine-induced nonmotor symptoms of Parkinson's disease.  

PubMed

Nonmotor symptoms of Parkinson's disease (PD) may emerge secondary to the underlying pathogenesis of the disease, while others are recognized side effects of treatment. Inevitably, there is an overlap as the disease advances and patients require higher dosages and more complex medical regimens. The non-motor symptoms that emerge secondary to dopaminergic therapy encompass several domains, including neuropsychiatric, autonomic, and sleep. These are detailed in the paper. Neuropsychiatric complications include hallucinations and psychosis. In addition, compulsive behaviors, such as pathological gambling, hypersexuality, shopping, binge eating, and punding, have been shown to have a clear association with dopaminergic medications. Dopamine dysregulation syndrome (DDS) is a compulsive behavior that is typically viewed through the lens of addiction, with patients needing escalating dosages of dopamine replacement therapy. Treatment side effects on the autonomic system include nausea, orthostatic hypotension, and constipation. Sleep disturbances include fragmented sleep, nighttime sleep problems, daytime sleepiness, and sleep attacks. Recognizing the non-motor symptoms that can arise specifically from dopamine therapy is useful to help optimize treatment regimens for this complex disease. PMID:21603184

Park, Ariane; Stacy, Mark

2011-01-01

269

Case Report: Subdural Hematoma in Grave's Disease Induced Thrombocytopenia.  

E-print Network

disorders it may occur spontaneously. It is a rare complication of immune thrombocytopenia. Here we report, in bleeding disorders it may occur spontaneously. It is a rare complication of immune thrombocytopenia.1 Mild increased to 2.8lacs/cumm. The final diagnosis was Grave's disease with anaemia and autoimmune

Carr, Leslie

270

Dopamine-Induced Nonmotor Symptoms of Parkinson's Disease  

PubMed Central

Nonmotor symptoms of Parkinson's disease (PD) may emerge secondary to the underlying pathogenesis of the disease, while others are recognized side effects of treatment. Inevitably, there is an overlap as the disease advances and patients require higher dosages and more complex medical regimens. The non-motor symptoms that emerge secondary to dopaminergic therapy encompass several domains, including neuropsychiatric, autonomic, and sleep. These are detailed in the paper. Neuropsychiatric complications include hallucinations and psychosis. In addition, compulsive behaviors, such as pathological gambling, hypersexuality, shopping, binge eating, and punding, have been shown to have a clear association with dopaminergic medications. Dopamine dysregulation syndrome (DDS) is a compulsive behavior that is typically viewed through the lens of addiction, with patients needing escalating dosages of dopamine replacement therapy. Treatment side effects on the autonomic system include nausea, orthostatic hypotension, and constipation. Sleep disturbances include fragmented sleep, nighttime sleep problems, daytime sleepiness, and sleep attacks. Recognizing the non-motor symptoms that can arise specifically from dopamine therapy is useful to help optimize treatment regimens for this complex disease. PMID:21603184

Park, Ariane; Stacy, Mark

2011-01-01

271

Rosuvastatin-Induced Arrest in Progression of Renal Disease  

Microsoft Academic Search

Preclinical and limited clinical data suggest that statins decrease the progressive decline in renal function that occurs in patients with renal disease. Pooled analysis of data obtained from a population of hyperlipidemic patients enrolled in the rosuvastatin (Crestor®) clinical development program permitted assessment of its effects on renal function both early and later in the course of treatment. Study participants

Donald G. Vidt; Michael D. Cressman; Susan Harris; John S. Pears; Howard G. Hutchinson

2004-01-01

272

Interferon induction by viruses. VIII. Vesicular stomatitis virus: (+-)DI-011 particles induce interferon in the absence of standard virions  

SciTech Connect

Evidence was presented that VSV (+-)DI-011 particles, which contain a genome of covalently linked totally self-complementary RNA, were excellent inducers of interferon (IFN) - by virtue of the dsRNA presumed to form within an infected cell, and that one molecule of that dsRNA per cell sufficed to induce a quantum yield of IFN. While the IFN-inducing capacity of (+-)DI-011 particle preparations has been confirmed, some researchers contend that DIP by themselves cannot induce IFN and that induction requires the presence of coinfecting (contaminating) standard VSV PFP. Consequently, we reexamined this question and now report that under five different conditions where the function of contaminating standard virus is reduced markedly, or eliminated, there was no diminution of the interferon-inducing particle (IFP) activity in preparations of (+-)DI-011 particles. Thus, inactivation of contaminating PFP by uv radiation or heat, the elimination (during induction) of cycling infection through the use of anti-serum (in the case of mouse L cells), and the reduction of PFP by four successive velocity sedimentation-gradient purifications had no adverse affect on the IFN-inducing capacity of DI-011 in either ''aged'' primary chick embryo cells or in mouse L(Y) cells. Furthermore, dilutions of DI-011 stocks which precluded the presence of even a single PFP still induced IFN in ''aged'' chick embryo cells. In concert these data demonstrate convincingly that IFN induction by DI-011 particles does not require coinfection with standard virus. It follows that DI-011 particles are intrinsically capable of inducing IFN.

Sekellick, M.J.; Marcus, P.I.

1982-02-01

273

Epigenetic transgenerational inheritance of vinclozolin induced mouse adult onset disease and associated sperm epigenome biomarkers.  

PubMed

The endocrine disruptor vinclozolin has previously been shown to promote epigenetic transgenerational inheritance of adult onset disease in the rat. The current study was designed to investigate the transgenerational actions of vinclozolin on the mouse. Transient exposure of the F0 generation gestating female during gonadal sex determination promoted transgenerational adult onset disease in F3 generation male and female mice, including spermatogenic cell defects, testicular abnormalities, prostate abnormalities, kidney abnormalities and polycystic ovarian disease. Pathology analysis demonstrated 75% of the vinclozolin lineage animals developed disease with 34% having two or more different disease states. Interestingly, the vinclozolin induced transgenerational disease was observed in the outbred CD-1 strain, but not the inbred 129 mouse strain. Analysis of the F3 generation sperm epigenome identified differential DNA methylation regions that can potentially be utilized as epigenetic biomarkers for transgenerational exposure and disease. PMID:23041264

Guerrero-Bosagna, Carlos; Covert, Trevor R; Haque, Md M; Settles, Matthew; Nilsson, Eric E; Anway, Matthew D; Skinner, Michael K

2012-12-01

274

Quinones and aromatic chemical compounds in particulate matter induce mitochondrial dysfunction: implications for ultrafine particle toxicity.  

PubMed

Particulate pollutants cause adverse health effects through the generation of oxidative stress. A key question is whether these effects are mediated by the particles or their chemical compounds. In this article we show that aliphatic, aromatic, and polar organic compounds, fractionated from diesel exhaust particles (DEPs), exert differential toxic effects in RAW 264.7 cells. Cellular analyses showed that the quinone-enriched polar fraction was more potent than the polycyclic aromatic hydrocarbon (PAH)-enriched aromatic fraction in O2 .- generation, decrease of membrane potential (Delta-Psi m), loss of mitochondrial membrane mass, and induction of apoptosis. A major effect of the polar fraction was to promote cyclosporin A (CsA)-sensitive permeability transition pore (PTP) opening in isolated liver mitochondria. This opening effect is dependent on a direct effect on the PTP at low doses as well as on an effect on Delta-Psi m at high doses in calcium (Ca2+)-loaded mitochondria. The direct PTP effect was mimicked by redox-cycling DEP quinones. Although the aliphatic fraction failed to perturb mitochondrial function, the aromatic fraction increased the Ca2+ retention capacity at low doses and induced mitochondrial swelling and a decrease in Delta-Psi m at high doses. This swelling effect was mostly CsA insensitive and could be reproduced by a mixture of PAHs present in DEPs. These chemical effects on isolated mitochondria could be reproduced by intact DEPs as well as ambient ultrafine particles (UFPs). In contrast, commercial polystyrene nanoparticles failed to exert mitochondrial effects. These results suggest that DEP and UFP effects on the PTP and Delta-Psi m are mediated by adsorbed chemicals rather than the particles themselves. PMID:15471724

Xia, Tian; Korge, Paavo; Weiss, James N; Li, Ning; Venkatesen, M Indira; Sioutas, Constantinos; Nel, Andre

2004-10-01

275

Amphetamine-induced taste aversion learning in young and old F-344 rats following exposure to 56Fe particles  

PubMed Central

Exposure to 56Fe particles produces changes in dopaminergic function and in dopamine-dependent behaviors, including amphetamine-induced conditioned taste aversion (CTA) learning. Because many of these changes are characteristic of the changes that accompany the aging process, the present study was designed to determine whether or not there would be an interaction between age and exposure to 56Fe particles in the disruption of an amphetamine-induced CTA. One hundred and forty F-344 male rats 2-, 7-, 12-, and 16-months old, were radiated with 56Fe particles (0.25–2.00 Gy, 1 GeV/n) at Brookhaven National Laboratory. Three days following irradiation, the rats were tested for the effects of radiation on the acquisition of a CTA produced by injection of amphetamine (3 mg/kg, i.p.). The main effect of age was to produce a significant decrease in conditioning day sucrose intake; there was no affect of age on the acquisition of the amphetamine-induced CTA. Exposing rats to 56Fe particles disrupted the acquisition of the CTA produced by injection of amphetamine only in the 2-month-old rats. These results do not support the hypothesis of an interaction between age and exposure to 56Fe particles in producing a disruption of amphetamine-induced CTA learning. As such, these results suggest that the aging produced by exposure to 56Fe particles may be endpoint specific. PMID:19424832

Carrihill-Knoll, K. L.; Shukitt-Hale, B.; Joseph, J. A.; Carey, A.

2007-01-01

276

Understanding the mechanisms of sickle cell disease by simulations with a discrete particle model  

NASA Astrophysics Data System (ADS)

Sickle cell disease (SCD) is an inherited blood disorder characterized by rigid, sickle-shaped red blood cells (RBCs). Because of their rigidity and shape, sickle cells can get stuck in smaller blood vessels, causing blockages and depriving oxygen to tissues. This study develops and applies mathematical models to better understand the mechanism of SCD. Two-dimensional models of RBCs and blood vessels have been constructed by representing them as discrete particles interacting with different forces. The nonlinear, elastic property of healthy RBCs could be adequately reproduced using a cosine angle bending force and a worm-like chain spring force. With the ability to deform, RBCs can squeeze through narrow blood vessels. In modeling sickle cells as rigid bodies and applying repelling and friction forces from the blood vessel, this study shows that geometrical factors (dimensions of the sickle cell and blood vessels) as well as rigidity and adhesiveness of the sickle cell all play an important role in determining how, and if, sickle cells become trapped within narrow blood capillaries. With lack of data to validate the model, this study primarily provides a sensitivity analysis of factors influencing sickle cell occlusion and identified critical data to support future modeling.

Hui, Katrina; Lin, Guang; Pan, Wenxiao

2013-01-01

277

A new mechanism for DNA alterations induced by alpha particles such as those emitted by radon and radon progeny.  

PubMed Central

The mechanism(s) by which alpha (alpha) particles like those emitted from inhaled radon and radon progeny cause their carcinogenic effects in the lung remains unclear. Although direct nuclear traversals by alpha-particles may be involved in mediating these outcomes, increasing evidence indicates that a particles can cause alterations in DNA in the absence of direct hits to cell nuclei. Using the occurrence of excessive sister chromatid exchanges (SCE) as an index of DNA damage in human lung fibroblasts, we investigated the hypothesis that alpha-particles may induce DNA damage through the generation of extracellular factors. We have found that a relatively low dose of alpha-particles can result in the generation of extracellular factors, which, upon transfer to unexposed normal human cells, can cause excessive SCE to an extent equivalent to that observed when the cells are directly irradiated with the same irradiation dose. A short-lived, SCE-inducing factor(s) is generated in alpha-irradiated culture medium containing serum in the absence of cells. A more persistent SCE-inducing factor(s), which can survive freeze-thaw and is heat labile is produced by fibroblasts after exposure to the alpha-particles. These results indicate that the initiating target for alpha-particle-induced genetic changes can be larger than a cell's nucleus or even a whole cell. How transmissible factors like those observed here in vitro may extend to the in vivo condition in the context of a-particle-induced carcinogenesis in the respiratory tract remains to be determined. PMID:9400706

Lehnert, B E; Goodwin, E H

1997-01-01

278

Hemolytic Disease of the Newborn Anti c Antibody Induced Hemolysis  

Microsoft Academic Search

Hemolytic disease in the newborn, as a cause of early jaundice, is not uncommon. This is mostly due to Rh (D), ABO incompatibility\\u000a and rarely due to other minor blood group incompatibility. The authors report two cases of Rh anti c isoimmunization presenting\\u000a as significant early neonatal jaundice within the 20 h of life. Both the babies were treated with intensive

Srinivas Murki; Hemasree Kandraju; Surekha A. Devi

279

Macromolecular prodrug of dexamethasone prevents particle-induced peri-implant osteolysis with reduced systemic side effects.  

PubMed

Aseptic implant loosening related to implant wear particle-induced inflammation is the most common cause of failure after joint replacement. Modulation of the inflammatory reaction to the wear products represents a rational approach for preventing aseptic implant failure. Long-term treatment using anti-inflammatory agents, however, can be associated with significant systemic side effects due to the drugs' lack of tissue specificity. To address this issue, N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-dexamethasone conjugate (P-Dex) was developed and evaluated for prevention of wear particle-induced osteolysis and the loss of fixation in a murine prosthesis failure model. Daily administration of free dexamethasone (Dex) was able to prevent wear particle-induced osteolysis, as assessed by micro-CT and histological analysis. Remarkably, monthly P-Dex administration (dose equivalent to free Dex treatment) was equally effective as free dexamethasone, but was not associated with systemic bone loss (a major adverse side effect of glucocorticoids). The reduced systemic toxicity of P-Dex is related to preferential targeting of the sites of wear particle-induced inflammation and its subcellular sequestration and retention by local inflammatory cell populations, resulting in sustained therapeutic action. These results demonstrate the feasibility of utilizing a macromolecular prodrug with reduced systemic toxicity to prevent wear particle-induced osteolysis. PMID:24326124

Ren, Ke; Dusad, Anand; Yuan, Fang; Yuan, Hongjiang; Purdue, P Edward; Fehringer, Edward V; Garvin, Kevin L; Goldring, Steven R; Wang, Dong

2014-02-10

280

Impact of Alcoholism and Alcohol Induced Disease on America  

E-print Network

Alcoholism is a serious disease that affects the lives of millions of Americans, devastates families, compromises national preparedness, depresses economic vitality, and burdens the country’s health care systems. This disease touches virtually all Americans. More than half of all adults have a family history of alcoholism or problem drinking. Three in ten adults 18 years of age and over have had alcoholism and/or engaged in alcohol abuse at some point in their lives and their drinking will impact their families, communities, and society as a whole. Untreated addiction costs America $400 billion annually and recent research indicates that alcoholism and alcohol abuse alone cost the nation’s economy approximately $185 billion each year. Fifteen percent of this amount is the cost of medical consequences and alcohol treatment; more than 70 percent is due to reduced, lost and forgone earnings; and the remainder is the cost of lost workforce productivity, accidents, violence, and premature death. 1 This paper documents the deleterious impact of heavy drinking, alcohol abuse and alcoholism on the United States. As explained more fully below, heavy drinking (defined as having five or more drinks in a single day at least once a week for males, and 4 or more for females), contributes to illness in each of the top three causes of death: heart disease, cancer, and

unknown authors

2011-01-01

281

Induced Systemic Resistance in Biocontrol of Plant Diseases  

Microsoft Academic Search

\\u000a Induction of resistance to pathogens by some strains of plant growth-promoting rhizobacteria (PGPR) and other microorganisms\\u000a is termed induced systemic resistance (ISR). In contrast to systemic acquired resistance, ISR develops as a result of the\\u000a colonization of plant roots by PGPR and other plant-beneficial microorganisms. ISR is mediated predominantly by a jasmonate-\\u000a or ethylene-sensitive pathway. Some strains of Pseudomonas, Bacillus,

Sudhamoy Mandal; Ramesh C. Ray

282

Induced Hatching to Avoid Infectious Egg Disease in Whitefish  

Microsoft Academic Search

Reacting to a threat before physical contact, e.g., induced by air- or water-borne substances [1], appears to be an elegant way of defense. The reaction may be behavioral [2–5], developmental, morphological, or physiological [5–7], and it can involve a shift in niche or life history [8, 9]. Hatching from eggs is a shift in niche and in life history. From

Claus Wedekind

2002-01-01

283

Role of Mutagenicity in Asbestos Fiber-Induced Carcinogenicity and Other Diseases  

PubMed Central

The cellular and molecular mechanisms of how asbestos fibers induce cancers and other diseases are not well understood. Both serpentine and amphibole asbestos fibers have been shown to induce oxidative stress, inflammatory responses, cellular toxicity and tissue injuries, genetic changes, and epigenetic alterations in target cells in vitro and tissues in vivo. Most of these mechanisms are believe to be shared by both fiber-induced cancers and noncancerous diseases. This article summarizes the findings from existing literature with a focus on genetic changes, specifically, mutagenicity of asbestos fibers. Thus far, experimental evidence suggesting the involvement of mutagenesis in asbestos carcinogenicity is more convincing than asbestos-induced fibrotic diseases. The potential contributions of mutagenicity to asbestos-induced diseases, with an emphasis on carcinogenicity, are reviewed from five aspects: (1) whether there is a mutagenic mode of action (MOA) in fiber-induced carcinogenesis; (2) mutagenicity/carcinogenicity at low dose; (3) biological activities that contribute to mutagenicity and impact of target tissue/cell type; (4) health endpoints with or without mutagenicity as a key event; and finally, (5) determinant factors of toxicity in mutagenicity. At the end of this review, a consensus statement of what is known, what is believed to be factual but requires confirmation, and existing data gaps, as well as future research needs and directions, is provided. PMID:21534089

Huang, Sarah X. L.; Jaurand, Marie-Claude; Kamp, David W.; Whysner, John; Hei, Tom K.

2011-01-01

284

Role of mutagenicity in asbestos fiber-induced carcinogenicity and other diseases.  

PubMed

The cellular and molecular mechanisms of how asbestos fibers induce cancers and other diseases are not well understood. Both serpentine and amphibole asbestos fibers have been shown to induce oxidative stress, inflammatory responses, cellular toxicity and tissue injuries, genetic changes, and epigenetic alterations in target cells in vitro and tissues in vivo. Most of these mechanisms are believe to be shared by both fiber-induced cancers and noncancerous diseases. This article summarizes the findings from existing literature with a focus on genetic changes, specifically, mutagenicity of asbestos fibers. Thus far, experimental evidence suggesting the involvement of mutagenesis in asbestos carcinogenicity is more convincing than asbestos-induced fibrotic diseases. The potential contributions of mutagenicity to asbestos-induced diseases, with an emphasis on carcinogenicity, are reviewed from five aspects: (1) whether there is a mutagenic mode of action (MOA) in fiber-induced carcinogenesis; (2) mutagenicity/carcinogenicity at low dose; (3) biological activities that contribute to mutagenicity and impact of target tissue/cell type; (4) health endpoints with or without mutagenicity as a key event; and finally, (5) determinant factors of toxicity in mutagenicity. At the end of this review, a consensus statement of what is known, what is believed to be factual but requires confirmation, and existing data gaps, as well as future research needs and directions, is provided. PMID:21534089

Huang, Sarah X L; Jaurand, Marie-Claude; Kamp, David W; Whysner, John; Hei, Tom K

2011-01-01

285

Shear-induced fat particle structure variation and the stability of food emulsions: I. Effects of shear history, shear rate and temperature  

Microsoft Academic Search

The shear-induced fat particle structure variation and the stability of food emulsions were investigated by the back-light scattering technique. The effects of temperature, shear rate, and shear history on the fat particle structure and stability of food emulsions were studied. Increasing the shear time initially improves the fat particle structure; afterwards, the fat particle packing structure becomes less ordered. The

Wen Xu; Alex Nikolov; Darsh T. Wasan

2005-01-01

286

Transmission dynamics of Tasmanian devil facial tumor disease may lead to disease-induced extinction.  

PubMed

Most pathogens threatening to cause extinction of a host species are maintained on one or more reservoir hosts, in addition to the species that is threatened by disease. Further, most conventional host-pathogen theory assumes that transmission is related to host density, and therefore a pathogen should become extinct before its sole host. Tasmanian devil facial tumor disease is a recently emerged infectious cancer that has led to massive population declines and grave concerns for the future persistence of this largest surviving marsupial carnivore. Here we report the results of mark-recapture studies at six sites and use these data to estimate epidemiological parameters critical to both accurately assessing the risk of extinction from this disease and effectively managing this disease threat. Three sites were monitored from before or close to the time of disease arrival, and at three others disease was well established when trapping began, in one site for at least 10 years. We found no evidence for sex-specific differences in disease prevalence and little evidence of consistent seasonal variation in the force of infection. At all sites, the disease was maintained at high levels of prevalence (>50% in 2-3-year-old animals), despite causing major population declines. We also provide the first estimates of the basic reproductive rate R0 for this disease. Using a simple age-structured deterministic model, we show that our results are not consistent with transmission being proportional to the density of infected hosts but are consistent with frequency-dependent transmission. This conclusion is further supported by the observation that local disease prevalence in 2-3-year-olds still exceeds 50% at a site where population density has been reduced by up to 90% in the past 12 years. These findings lend considerable weight to concerns that this host-specific pathogen will cause the extinction of the Tasmanian devil. Our study highlights the importance of rapidly implementing monitoring programs to determine how transmission depends on host density and emphasizes the need for ongoing management strategies involving a disease-free "insurance population," along with ongoing field monitoring programs to confirm whether local population extinction occurs. PMID:20120807

McCallum, Hamish; Jones, Menna; Hawkins, Clare; Hamede, Rodrigo; Lachish, Shelly; Sinn, David L; Beeton, Nick; Lazenby, Billie

2009-12-01

287

Dust-induced interstitial lung disease in the tropics.  

PubMed

Inhalation of dusts is an important cause of interstitial lung disease in the tropical countries such as India. While dusts of organic origin, such as the cotton dust causing byssinosis, generally cause bronchial or bronchiolar involvement and hypersensitivity pneumonitis, inorganic metallic dusts cause progressive pulmonary fibrosis. Silicosis, coal workers' pneumoconiosis, and asbestosis are the three most commonly recognized forms of pneumoconiotic pulmonary fibrosis. Pulmonary tuberculosis is an important complication seen in up to 50% of patients of silicosis in some reports from India. The presentation is generally chronic, although acute and accelerated forms of silicosis are known when the exposures are heavy. Breathlessness, dry cough, and general constitutional symptoms are commonly seen. Patients with silicotuberculosis or other forms of infection may also have significant expectoration, hemoptysis, fever, and rapid progression. Respiratory failure and chronic cor pulmonale occur in the later stages. The diagnosis is easily established if the occupational history is available. Dense nodular opacities on chest roentgenograms, which may be large in patients with massive pulmonary fibrosis, are characteristic. Emphysematous changes generally appear in advanced stages or in patients who smoke. Bronchoalveolar lavage and/or lung biopsy may occasionally be required to establish or exclude other causes of interstitial lung disease. Treatment is largely palliative, although a variety of drugs including corticosteroids and procedures such as whole lung lavage have been tried. None of these methods has yet been found successful in the treatment. Preventive safety steps, including removal of the patient from the site of exposure, are the only effective strategies to control disease progression. PMID:11584175

Jindal, S K; Aggarwal, A N; Gupta, D

2001-09-01

288

A case of venlafaxine-induced interstitial lung disease.  

PubMed

A patient treated with venlafaxine for major depression developed an interstitial lung disease (ILD) with the characteristic clinical, radiological and pathological features of chronic hypersensitivity pneumonitis. A high resolution computed tomography scan demonstrated ground glass opacity, mosaic perfusion with air-trapping and traction bronchiectasis in both lungs. The pathological findings were consistent with a nonspecific interstitial pneumonia pattern. Clinical and radiological improvements were noted after the discontinuation of venlafaxine and the administration of a corticosteroid. This report provides further evidence that the anti-depressant venlafaxine can cause ILD. PMID:25237379

Oh, Serim; Cha, Seung-Ick; Kim, Hyera; Kim, Minjung; Choi, Sun Ha; Seo, Hyewon; Park, Tae-In

2014-08-01

289

Anacardic acids from cashew nuts ameliorate lung damage induced by exposure to diesel exhaust particles in mice.  

PubMed

Anacardic acids from cashew nut shell liquid, a Brazilian natural substance, have antimicrobial and antioxidant activities and modulate immune responses and angiogenesis. As inflammatory lung diseases have been correlated to environmental pollutants exposure and no reports addressing the effects of dietary supplementation with anacardic acids on lung inflammation in vivo have been evidenced, we investigated the effects of supplementation with anacardic acids in a model of diesel exhaust particle- (DEP-) induced lung inflammation. BALB/c mice received an intranasal instillation of 50? ? g of DEP for 20 days. Ten days prior to DEP instillation, animals were pretreated orally with 50, 150, or 250?mg/kg of anacardic acids or vehicle (100? ? L of cashew nut oil) for 30 days. The biomarkers of inflammatory and antioxidant responses in the alveolar parenchyma, bronchoalveolar lavage fluid (BALF), and pulmonary vessels were investigated. All doses of anacardic acids ameliorated antioxidant enzyme activities and decreased vascular adhesion molecule in vessels. Animals that received 50?mg/kg of anacardic acids showed decreased levels of neutrophils and tumor necrosis factor in the lungs and BALF, respectively. In summary, we demonstrated that AAs supplementation has a potential protective role on oxidative and inflammatory mechanisms in the lungs. PMID:23533495

Carvalho, Ana Laura Nicoletti; Annoni, Raquel; Torres, Larissa Helena Lobo; Durão, Ana Carolina Cardoso Santos; Shimada, Ana Lucia Borges; Almeida, Francine Maria; Hebeda, Cristina Bichels; Lopes, Fernanda Degobbi Tenorio Quirino Santos; Dolhnikoff, Marisa; Martins, Milton Arruda; Silva, Luiz Fernando Ferraz; Farsky, Sandra Helena Poliselli; Saldiva, Paulo Hilário Nascimento; Ulrich, Cornelia M; Owen, Robert W; Marcourakis, Tania; Trevisan, Maria Teresa Salles; Mauad, Thais

2013-01-01

290

Anacardic Acids from Cashew Nuts Ameliorate Lung Damage Induced by Exposure to Diesel Exhaust Particles in Mice  

PubMed Central

Anacardic acids from cashew nut shell liquid, a Brazilian natural substance, have antimicrobial and antioxidant activities and modulate immune responses and angiogenesis. As inflammatory lung diseases have been correlated to environmental pollutants exposure and no reports addressing the effects of dietary supplementation with anacardic acids on lung inflammation in vivo have been evidenced, we investigated the effects of supplementation with anacardic acids in a model of diesel exhaust particle- (DEP-) induced lung inflammation. BALB/c mice received an intranasal instillation of 50??g of DEP for 20 days. Ten days prior to DEP instillation, animals were pretreated orally with 50, 150, or 250?mg/kg of anacardic acids or vehicle (100??L of cashew nut oil) for 30 days. The biomarkers of inflammatory and antioxidant responses in the alveolar parenchyma, bronchoalveolar lavage fluid (BALF), and pulmonary vessels were investigated. All doses of anacardic acids ameliorated antioxidant enzyme activities and decreased vascular adhesion molecule in vessels. Animals that received 50?mg/kg of anacardic acids showed decreased levels of neutrophils and tumor necrosis factor in the lungs and BALF, respectively. In summary, we demonstrated that AAs supplementation has a potential protective role on oxidative and inflammatory mechanisms in the lungs. PMID:23533495

Carvalho, Ana Laura Nicoletti; Annoni, Raquel; Torres, Larissa Helena Lobo; Durao, Ana Carolina Cardoso Santos; Shimada, Ana Lucia Borges; Almeida, Francine Maria; Hebeda, Cristina Bichels; Lopes, Fernanda Degobbi Tenorio Quirino Santos; Dolhnikoff, Marisa; Martins, Milton Arruda; Silva, Luiz Fernando Ferraz; Farsky, Sandra Helena Poliselli; Saldiva, Paulo Hilario Nascimento; Ulrich, Cornelia M.; Owen, Robert W.; Marcourakis, Tania; Trevisan, Maria Teresa Salles; Mauad, Thais

2013-01-01

291

Maintenance of surgically induced remission of Crohn's disease.  

PubMed

At 1 year after a first resection, up to 80% of patients show an endoscopic recurrence, 10-20% have clinical relapse, and 5% have surgical recurrence. Smoking is one of the most important risk factors for postoperative recurrence. Preoperative disease activity and the severity of endoscopic lesions in the neoterminal ileum within the first postoperative year are predictors of symptomatic recurrence. Mesalazine is generally the first-line treatment used in the postoperative setting but still provokes considerable controversy as to its efficacy, in spite of the results of a meta-analysis. Immunosuppressive treatment (azathioprine, 6-mercaptopurine) is based on scant evidence but is currently used as a second-line treatment in postsurgical patients at high risk for recurrence, with symptoms or with early endoscopic lesions in the neoterminal ileum. Nitroimidazole antibiotics (metronidazole, ornidazole) are also effective in the control of active Crohn's disease in the postoperative setting. Given their known toxicity, they may be used as a third-line treatment as initial short-term prevention therapy rather than in the long term. Conventional corticosteroids, budesonide or probiotics have no proven role in postoperative prophylaxis. Infliximab has not as yet been studied for use in the prevention of relapse after surgery. PMID:18239404

Froehlich, Florian; Juillerat, Pascal; Pittet, Valérie; Felley, Christian; Mottet, Christian; Vader, John-Paul; Michetti, Pierre; Gonvers, Jean-Jacques

2007-01-01

292

Nuclear physics of cosmic ray interaction with semiconductor materials: Particle-induced soft errors from a physicist's perspective  

Microsoft Academic Search

The key issues of cosmic-ray-induced soft-error rates, SER (also referred to as single-event upset, SEU, rates) in microelectronic devices are discussed from the viewpoint of fundamental atomic and nuclear interactions between high-energy particles and semiconductors. From sea level to moderate altitudes, the cosmic ray spectrum is dominated by three particle species: nucleons (protons and neutrons), pions, and muons. The characteristic

Henry H. K. Tang

1996-01-01

293

Modeling particle-induced electron emission in a simplified plasma Test Cell  

SciTech Connect

Particle-induced electron emission (PIE) is modeled in a simplified, well-characterized plasma Test Cell operated at UCLA. In order for PIE to be a useful model in this environment, its governing equations are first reduced to lower-order models which can be implemented in a direct simulation Monte Carlo and Particle-in-Cell framework. These reduced-order models are described in full and presented as semi-empirical models. The models are implemented to analyze the interaction of low- and high-energy ({approx}1-2 keV) xenon ions and atoms with the stainless steel electrodes of the Test Cell in order to gain insight into the emission and transport of secondary electrons. Furthermore, there is a lack of data for xenon-stainless steel atom- and ion-surface interactions for similar environments. Using experimental data as a reference, both total yields and emitted electron energy distribution functions can be deduced by observing sensitivities of current collection results to these numerical models and their parameters.

Giuliano, Paul N.; Boyd, Iain D. [Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2013-03-21

294

Particle Induced X-Ray Emission Analysis of Atmospheric Aerosols Collected in Upstate New York  

NASA Astrophysics Data System (ADS)

Elemental analysis of atmospheric aerosols collected in the historic Stockade District of Schenectady, New York, was performed using particle induced X-ray emission (PIXE) spectroscopy. This is part of a systematic study in the Mohawk River Valley of upstate New York to identify the sources and understand the transport, transformation, and effects of airborne pollutants and the connection between aerosols, the deposition of pollution, and the uptake of pollutants by wildlife and vegetation. The atmospheric aerosols were collected with a nine-stage cascade impactor that allows for the analysis of the particulate matter as a function of particle size. The samples were bombarded with 2-MeV proton beams from the Union College Pelletron Accelerator and the energy spectra of the X-rays were measured with a silicon drift detector. The X-ray spectra were analyzed using GUPIX software to extract the elemental concentrations of the particulate matter. The sample collection and analysis will be described, and preliminary results will be presented.

Gleason, Colin; Harrington, Charles; Schuff, Katie; Labrake, Scott; Vineyard, Michael

2009-10-01

295

Nanosized titanium dioxide particles do not induce DNA damage in human peripheral blood lymphocytes.  

PubMed

Industrial application of titanium dioxide nanoparticles (TiO(2) -NPs) as an additive in pharmaceutical and cosmetic products is increasing. However, the knowledge about the toxicity of this material is still incomplete and data concerning health and environmental safety and results of recent studies on TiO(2) nanotoxicology are inconsistent. The in vitro geno- and cytotoxicity of TiO(2) -NPs in the anatase crystal phase was evaluated in human peripheral blood lymphocytes from 10 male donors. Initially, transmission electron microscopy (TEM) was performed to describe particle morphology and size, the degree of particle aggregation, and the intracellular distribution. Cells were exposed to nanoparticles in increasing concentrations of 20, 50, 100, and 200 ?g/ml for 24 hr. Cytotoxic effects were analyzed by trypan blue exclusion test and the single-cell microgel electrophoresis (comet) assay was applied to detect DNA double-strand breakage. TiO(2) -NPs were sphere shaped with a diameter of 15-30 nm. Despite dispersive pretreatment, a strong tendency to form aggregates was observed. Particles were detected in the cytoplasm of lymphocytes, but also a transfer into the nucleus was seen. The trypan blue exclusion test did not show any decrease in lymphocyte viability, and there was no evidence of genotoxicity in the comet assay for any of the tested concentrations. In conclusion, TiO(2) -NPs reached the cytoplasm as well as the nucleus and did not induce cyto- or genotoxic effects in human peripheral blood lymphocytes. Complement investigations on different human cell systems will be performed to estimate the biocompatibility of TiO(2) -NPs. Environ. Mol. Mutagen. PMID:20740634

Hackenberg, Stephan; Friehs, Gudrun; Kessler, Michael; Froelich, Katrin; Ginzkey, Christian; Koehler, Christian; Scherzed, Agmal; Burghartz, Marc; Kleinsasser, Norbert

2011-05-01

296

A model for vehicle-induced non-tailpipe emissions of particles along Swedish roads  

NASA Astrophysics Data System (ADS)

One of the most important parameters that controls the suspension of road dust particles in the air is road surface moisture. This is calculated every hour from a budget equation that takes into account precipitation, evaporation and runoff. During wet conditions a road dust layer is built up from road wear which strongly depends on the use of studded tyres and road sanding. The dust layer is reduced during dry road conditions by suspension of particles due to vehicle-induced turbulence. The dust layer is also reduced by wash-off due to precipitation. Direct non-tailpipe vehicle emissions due to the wear and tear of the road surface, brakes and tyres are accounted for in the traditional way as constant emission factors expressed as mass emitted per vehicle kilometre. The model results are compared with measurements from both a narrow street canyon in the city centre of Stockholm and from an open highway outside the city. The model is able to account for the main features in the day-to-day mean PM 10 variability for the street canyon and for the highway. A peak in the PM 10 concentration is typically observed in late winter and early spring in the Nordic countries where studded tyres are used. This behaviour is due to a combination of factors: frequent conditions with dry roads, high number of cars with studded tyres and an accumulated road dust layer that increases suspension of particles. The study shows that using a constant emission factor for PM 10 or relating PM 10 emissions to NO x cannot be used for prediction of day-to-day variations in PM 10 concentrations in the traffic environments studied here. The model needs to describe variations in dust load, wetness of the road and how dust suspension interacts with these processes.

Omstedt, G.; Bringfelt, B.; Johansson, C.

297

Exposure to wear particles generated from studded tires and pavement induces inflammatory cytokine release from human macrophages.  

PubMed

Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. Lately, wear particles generated from traffic have been recognized to be a major contributing source to the overall particle load, especially in the Nordic countries were studded tires are used. In this work, we investigated the inflammatory effect of PM10 generated from the wear of studded tires on two different types of pavement. As comparison, we also investigated PM10 from a traffic-intensive street, a subway station, and diesel exhaust particles (DEP). Human monocyte-derived macrophages, nasal epithelial cells (RPMI 2650), and bronchial epithelial cells (BEAS-2B) were exposed to the different types of particles, and the secretion of IL-6, IL-8, IL-10, and TNF-alpha into the culture medium was measured. The results show a significant release of cytokines from macrophages after exposure for all types of particles. When particles generated from asphalt/granite pavement were compared to asphalt/quartzite pavement, the granite pavement had a significantly higher capacity to induce the release of cytokines. The granite pavement particles induced cytokine release at the same magnitude as the street particles did, which was higher than what particles from both a subway station and DEP did. Exposure of epithelial cells to PM10 resulted in a significant increase of TNF-alpha secreted from BEAS-2B cells for all types of particles used (DEP was not tested), and the highest levels were induced by subway particles. None of the particle types were able to evoke detectable cytokine release from RPMI 2650 cells. The results indicate that PM10 generated by the wear of studded tires on the street surface is a large contributor to the cytokine-releasing ability of particles in traffic-intensive areas and that the type of pavement used is important for the level of this contribution. Furthermore, the airway inflammatory potential of wear particles from tires and pavement might be of a greater magnitude than that of DEP. PMID:16608163

Lindbom, John; Gustafsson, Mats; Blomqvist, Göran; Dahl, Andreas; Gudmundsson, Anders; Swietlicki, Erik; Ljungman, Anders G

2006-04-01

298

Moisture-induced surface crystallization of spray-dried amorphous lactose particles studied by atomic force microscopy.  

PubMed

The aim of this study was to show that atomic force microscopy (AFM) can be used to obtain mechanistic and kinetic information about the process of moisture-induced surface crystallization of single particles of amorphous lactose. Completely amorphous lactose particles were prepared by spray-drying a solution of alpha-lactose monohydrate, and moisture-induced crystallization was monitored for a bed of particles by microcalorimetry and for single particles by AFM. From the AFM images it was found that crystallization of the surface of single particles can be described in terms of a sequence of three events: an initial smoothening of the surface, formation of crystalline nanostructures dispersed in amorphous material, and growth of these structures to a complete crystalline surface. The surface roughness parameter rugosity was used to estimate the fraction crystalline surface, and the growth kinetics were found to obey the JMAK equation. The fraction crystalline surface at different times could also be estimated by determining the growth rate of individual crystals. It was concluded that AFM offers a unique means of visualizing the process of moisture-induced surface crystallization of amorphous particles and enables mechanistic and kinetic information about the process to be extracted. PMID:14648633

Mahlin, Denny; Berggren, Jonas; Alderborn, Göran; Engström, Sven

2004-01-01

299

Diesel Exhaust Particles Induce Cysteine Oxidation and S-Glutathionylation in House Dust Mite Induced Murine Asthma  

PubMed Central

Background Diesel exhaust particle (DEP) exposure enhances allergic inflammation and has been linked to the incidence of asthma. Oxidative stress on the thiol molecules cysteine (Cys) and glutathione (GSH) can promote inflammatory host responses. The effect of DEP on the thiol oxidation/reduction (redox) state in the asthmatic lung is unknown. Objective To determine if DEP exposure alters the Cys or GSH redox state in the asthmatic airway. Methods Bronchoalveolar lavage fluid was obtained from a house dust mite (HDM) induced murine asthma model exposed to DEP. GSH, glutathione disulfide (GSSG), Cys, cystine (CySS), and s-glutathionylated cysteine (CySSG) were determined by high pressure liquid chromatography. Results DEP co-administered with HDM, but not DEP or HDM alone, decreased total Cys, increased CySS, and increased CySSG without significantly altering GSH or GSSG. Conclusions DEP exposure promotes oxidation and S-glutathionylation of cysteine amino acids in the asthmatic airway, suggesting a novel mechanism by which DEP may enhance allergic inflammatory responses. PMID:23555996

Lee, Gerald B.; Brandt, Eric B.; Xiao, Chang; Gibson, Aaron M.; Le Cras, Timothy D.; Brown, Lou Ann S.; Fitzpatrick, Anne M.; Khurana Hershey, Gurjit K.

2013-01-01

300

Epicuticular lipids induce aggregation in Chagas disease vectors  

PubMed Central

Background The triatomine bugs are vectors of the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. Aggregation behavior plays an important role in their survival by facilitating the location of refuges and cohesion of aggregates, helping to keep them safely assembled into shelters during daylight time, when they are vulnerable to predators. There are evidences that aggregation is mediated by thigmotaxis, by volatile cues from their faeces, and by hexane-extractable contact chemoreceptive signals from their cuticle surface. The epicuticular lipids of Triatoma infestans include a complex mixture of hydrocarbons, free and esterified fatty acids, alcohols, and sterols. Results We analyzed the response of T. infestans fifth instar nymphs after exposure to different amounts either of total epicuticular lipid extracts or individual lipid fractions. Assays were performed in a circular arena, employing a binary choice test with filter papers acting as aggregation attractive sites; papers were either impregnated with a hexane-extract of the total lipids, or lipid fraction; or with the solvent. Insects were significantly aggregated around papers impregnated with the epicuticular lipid extracts. Among the lipid fractions separately tested, only the free fatty acid fraction promoted significant bug aggregation. We also investigated the response to different amounts of selected fatty acid components of this fraction; receptiveness varied with the fatty acid chain length. No response was elicited by hexadecanoic acid (C16:0), the major fatty acid component. Octadecanoic acid (C18:0) showed a significant assembling effect in the concentration range tested (0.1 to 2 insect equivalents). The very long chain hexacosanoic acid (C26:0) was significantly attractant at low doses (? 1 equivalent), although a repellent effect was observed at higher doses. Conclusion The detection of contact aggregation pheromones has practical application in Chagas disease vector control. These data may be used to help design new tools against triatomine bugs. PMID:19173716

Figueiras, Alicia N Lorenzo; Girotti, Juan R; Mijailovsky, Sergio J; Juarez, M Patricia

2009-01-01

301

Evaluation of hydrophobic and hydrophilic kaolin particle films for peach crop, arthropod and disease management.  

PubMed

Hydrophobic and/or hydrophilic kaolin particle film treatments to peach (Prunus persica (L) Batsch) trees were evaluated for crop and pest management capabilities in six studies from 1997 to 2000. Unsprayed control and standard treatments, the latter consisting of a commercial pesticide program, were included for comparison. Treatments in initial studies were applied via handgun, which resulted in a uniform and heavy deposit of kaolin after the first application. In contrast, treatments in subsequent studies used airblast equipment, which provided a uniform but less dense coverage, even after multiple applications. Results showed that both formulations of kaolin provided control of oriental fruit moth (Grapholita molesta (Busck)), plum curculio (Conotrachelus nenuphar (Herbst)) and Japanese beetle (Popillia japonica Newman) that was comparable with or better than the standard pesticide program. Effective management of late season catfacing insects (tarnished plant bugs Lygus lineolaris (Palisot de Beauvois) and stinkbugs Acrosternum hilare (Say), Euschistus servus (Say), and E tristigmus (Say)) and leafrollers (undetermined species) was also observed, although kaolin applications significantly increased phytophagous mite (Panonychus ulmi (Koch)) levels. In contrast to arthropod management, kaolin failed to control either peach scab (Cladosporium carpophilum (Von Thumen)) or rusty spot (Podosphaera leucotricha (Ell and Ev) ES Salmon) in any of the 4 years of the study. However, hydrophobic kaolin provided effective brown rot (Monilinia fructicola (G Winter) Honey) control when applied via handgun, and partial control when applied via airblast; hydrophilic kaolin failed to provide any control. These results suggest that hydrophobicity and deposit density may be important factors for effective disease management. The application of kaolin significantly delayed fruit maturation, increased fruit size and increased soluble solids relative to the standard. This effect, attributed to a reduction in plant stress, also resulted in increased fruit number and yield on young trees, indicating that an accentuated beneficial response from kaolin applications may be possible. PMID:15593071

Lalancette, Norman; Belding, Robert D; Shearer, Peter W; Frecon, Jerome L; Tietjen, William H

2005-01-01

302

Clinical Features, Pathophysiology, and Treatment of Levodopa-Induced Dyskinesias in Parkinson's Disease  

PubMed Central

Dyskinetic disorders are characterized by excess of motor activity that may interfere with normal movement control. In patients with Parkinson's disease, the chronic levodopa treatment induces dyskinetic movements known as levodopa-induced dyskinesias (LID). This paper analyzed the pathophysiology, clinical manifestations, pharmacological treatments, and surgical procedures to treat hyperkinetic disorders. Surgery is currently the only treatment available for Parkinson's disease that may improve both parkinsonian motor syndrome and LID. However, this paper shows the different mechanisms involved are not well understood. PMID:23125942

Guridi, J.; Gonzalez-Redondo, R.; Obeso, J. A.

2012-01-01

303

[Assessment of risk for occupationally induced diseases in purification plant workers at a petroleum refinery].  

PubMed

The risk for occupationally induced diseases was assessed in purification plant workers at a petroleum refinery. The auxiliary process (purification and prepurification plants, biochemical purification) of the refinery OAO "Naftan" was the study object. Epidemiological, sanitary-and-hygienic studies were conducted to examine the negative influence of dangerous and harmful production factors on the workers' health status. The harmful and dangerous production factors recorded at this enterprise have been found to have a negative influence on the workers' health workers, which leads to the development of occupationally induced diseases in them. PMID:21598648

Chebotarev, P A; Kharlashova, N V

2011-01-01

304

Detection of rhinovirus in induced sputum at exacerbation of chronic obstructive pulmonary disease  

Microsoft Academic Search

Detection of rhinovirus in induced sputum at exacerbation of chronic obstructive pulmonary disease. T.A.R. Seemungal, R. Harper-Owen, A. Bhowmik, D.J. Jeffries, J.A. Wedzicha. #ERS Journals Ltd 2000. ABSTRACT: Common colds are associated with exacerbations of chronic obstructive pulmonary disease (COPD). However, the role of the common cold virus (human rhinovirus) in the production of symptoms and lower airway inflammation at

T. A. R. Seemungal; R. Harper-Owen; A. Bhowmik; D. J. Jeffries; J. A. Wedzicha

2000-01-01

305

c-myc as an inducer of polycystic kidney disease in transgenic mice  

Microsoft Academic Search

c-myc as an inducer of polycystic kidney disease in transgenic mice. In this study, a genetic model of polycystic kidney disease (PKD) has been produced in transgenic mice bearing the murine c-mycgene driven by the SV40 enhancer and the adult ?-globin promoter. These animals reproducibly develop PKD and die of renal failure. The phenotype appears to result from the overexpression

Marie Trudel; Vivette D'Agati; Frank Costantini

1991-01-01

306

The Pathogenic Role of Macrophage Migration Inhibitory Factor in Immunologically Induced Kidney Disease in the Rat  

Microsoft Academic Search

Summary Macrophage migration inhibitory factor (MIF) plays a pivotal role in the inflammatory response in endotoxemia and in the delayed-type hypersensitivity response, but its potential as a regula- tor of immunologically induced disease is unknown. We have addressed this issue by adminis- tering a neutralizing anti-MIF antibody in a rat model of immunologically induced crescentic anti-glomerular basement membrane (GBM) glomerulonephritis.

Hui Y. Lan; Michael Bacher; Niansheng Yang; Wei Mu; David J. Nikolic-Paterson; Christine Metz; Andreas Meinhardt; Richard Bucala; Robert C. Atkins

2010-01-01

307

Laboratory experiments on the determination of polycyclic aromatic hydrocarbon coverage of submicrometer particles by laser-induced aerosol photoemission  

SciTech Connect

First measurements of laser-induced photoelectric charging of submicrometer particles with different polycyclic aromatic hydrocarbon (PAH) coatings are presented. Pure carbon and NaCl particles were generated, and a monodisperse fraction was selected for subsequent coating with a PAH. The growth of the particles due to PAH adsorption or condensation was controlled with a screen type diffusion battery with a resolution better than 1 nm. These aerosols were irradiated with an excimer-laser-pumped dye laser that was frequency-doubled with a BBO crystal. Once photoelectrons were emitted, the remaining positively charged particles were detected with an aerosol electrometer. Wavelengths between 207.5 and 241 nm were investigated. Pure NaCl particles showed a clearly nonlinear behavior when irradiated with increasing energy density of the laser at a fixed wavelength, while pure carbon particles showed a linear behavior. The spectral dependences of the charging of NaCl and carbon particles are given for different PAH submonolayer coatings. Emission of coated NaCl particles is enhanced for all the PAHs, while in the case of carbon particles different PAHs had a different influence on the emission.

Niessner, R.; Robers, W.; Wilbring, P.

1989-02-15

308

Concentrated ambient ultrafine particle exposure induces cardiac change in young healthy volunteers  

EPA Science Inventory

Exposure to ambient ultrafine particles has been associated with cardiopulmonary toxicity and mortality. Adverse effects specifically linked to ultrafine particles include loss of sympathovagal balance and altered hemostasis. To characterize the effects of ultrafine particles in ...

309

Expression of ORF A1 of infectious bursal disease virus results in the formation of virus-like particles  

Microsoft Academic Search

A recombinant vaccinia virus inducibly expressing ORF A1 of infectious bursal disease virus (IBDV) has been constructed and characterized. Cells infected with this recombinant virus express the IBDV poly- protein, which is proteolytically processed to give mature VP2, VP3, and VP4 polypeptides. An elec- tron microscopy study revealed that the cytoplasm of cells infected with the recombinant virus contains abundant

A. Ferna; C. Risco; S. Marti; J. P. Albar; J. F. Rodri; Estructura de Macromole

310

Oncogene-Induced Senescence as a New Mechanism of Disease: The Paradigm of Erdheim–Chester Disease  

PubMed Central

Erdheim–Chester disease (ECD) is a rare form of systemic histiocytosis characterized by the diffuse infiltration of tissues by lipid-laden macrophages. As the clinical course and prognosis are highly influenced by site of disease involvement, ECD course ranges from asymptomatic to life threatening, with a reported global 5-year mortality of 30–40%. Whether ECD is an inflammatory or clonal disease in its nature has long been debated. The disease is characterized by a network of pro-inflammatory cyto/chemokines responsible for the recruitment and activation of histiocytes into ECD lesions, similarly to what reported in Langerhans cell histiocytosis (LCH). Growing evidence supports a central role of the oncogenic BRAFV600E mutation in histiocytosis pathogenesis, and suggests oncogene-induced senescence (OIS), a major protective mechanism against oncogenic events characterized by cell-cycle arrest and the induction of pro-inflammatory molecules, as the possible link between the oncogenic mutation and the observed inflammation. Indeed, ECD recapitulates in vivo the molecular events associated with OIS, i.e., cell-cycle arrest and a potent local inflammatory response. Accordingly, the infiltration of different tissues by macrophages and the inflammatory local and systemic effects observed in ECD likely represent a drawback of OIS. Therefore, these findings delineate a new conception of OIS as a new pathogenic mechanism intrinsically responsible for disease development. PMID:24982657

Cavalli, Giulio; Biavasco, Riccardo; Borgiani, Bruno; Dagna, Lorenzo

2014-01-01

311

Neutrino-Induced Reactions for Nucleosynthesis by the Quasi-particle RPA  

NASA Astrophysics Data System (ADS)

We calculated neutrino-induced reactions in the energy range below the quasi-elastic region for nuclei of astrophysical importance. Neutrino-induced reactions have been found to be important for the nucleosynthesis in core collapsing supernovae explosions because expected neutrino flux is sufficiently high enough to excite many relevant nuclei in spite of small cross sections of the weak interaction. Our calculations are carried out with the Quasi-particle Random Phase Approximation (QRPA), which successfully described the nuclear beta decays of relevant nuclei by taking neutron-proton pairing as well as neutron-neutron and proton-proton pairing correlations into account. To describe neutrino-nucleus reactions, general multipole transitions by the weak interaction with finite momentum transfers are considered for neutral and charged current reactions. Both reactions are described in a theoretical framework. Our results are shown to well reproduce the sparse experimental data and extended further for neutrino reactions on various nuclear targets. Parts of the results are reported in this talk.

Cheoun, Myung-Ki; Ha, Eunja; Kajino, T.

2010-08-01

312

Enalapril protects endothelial cells against induced apoptosis in Alzheimer's disease  

PubMed Central

Background: Alzheimer's disease (AD) is a progressive neurodegenerative disease in which endothelial cell (EC) can be affected. In brain, functional changes in ECs contribute to reductions in resting blood flow. Furthermore, angiotensin-converting enzyme inhibitors (ACE-I) have beneficial effects on endothelial dysfunction. This is the first study that presents direct experimental evidence associating endothelial apoptosis as a basis of AD pathogenesis and response to an ACE-I therapy. Materials and Methods: Human umbilical vein ECs (HUVECs) were treated with sera from AD patients and sera from healthy volunteers (each group, n = 10). Apoptosis was determined by annexin V–propidium iodide staining and cell death detection kit. The effect of 50 ?M enalapril on endothelial apoptosis was assessed. Nitrite (NO2?) levels were determined in the culture supernatants. Results: Enalapril suppressed the induction of apoptosis by the serum of patients only when used before treating HUVECs with the sera of AD. Mean ± SD of apoptosis induction in the control group was 6.7 ± 3.69; in the group treated with sera of AD for 24 h was 47.78 ± 0.65; in the group wherein sera from AD was added (pretreatment) after exposure of HUVECs by 50 ?M enalapril for 24 h was 26.6 ± 2.63; and in the group wherein HUVECs were exposed in the sera of AD for 24 h and then 50 ?M enalapril was added to these cells for another 24 h (post-treatment) was 56.87 ± 5.51. Also, the mean ± SD of NO2? concentration showed significantly greater levels of dissolved NO2/NO3 metabolite in the culture media of untreated HUVECs by enalapril (1.03 ± 0.06) as compared with control (0.26 ± 0.13; P < 0.05), while the rate of nitric oxide (NO) significantly decreased when enalapril was presented in culture both in the pretreatment (0.07 ± 0.003) and in the post-treatment group (0.06 ± 0.005; P < 0.05). Conclusion: It could be concluded that EC treated with sera from AD patients activates apoptosis in HUVECs; this effect was reversed by enalapril pretreatment. This can be proposed as a therapeutic approach for Alzheimer's patients. PMID:23961275

Meamar, Rokhsareh; Dehghani, Leila; Ghasemi, Majid; Saadatnia, Mohamad; Basiri, Keivan; Faradonbeh, Nazanin Alaei; Javanmard, Shaghayegh Haghjooy

2013-01-01

313

Measurement of Beta Particles Induced Electron-Hole Pairs Recombination in Depletion Region of GaAs PN Junction  

Microsoft Academic Search

PN junctions and schottky diodes are widely employed as electron-hole pair collectors in electron beam induced current (EBIC) techniques and betavoltaic batteries, in which the recombination in depletion regions is ignored. We measured the beta particles induced electron-hole pairs recombination in the depletion region of a GaAs P+PN+ junction, based on comparisons between measured short currents and ideal values. The

Hai-Yang Chen; Lan Jiang; Da-Rang Li

2011-01-01

314

Inositol Hexakisphosphate Kinases Induce Cell Death in Huntington Disease  

PubMed Central

Inositol pyrophosphate diphosphoinositol pentakisphosphate is ubiquitously present in mammalian cells and contains highly energetic pyrophosphate bonds. We have previously reported that inositol hexakisphosphate kinase type 2 (InsP6K2), which converts inositol hexakisphosphate to inositol pyrophosphate diphosphoinositol pentakisphosphate, mediates apoptotic cell death via its translocation from the nucleus to the cytoplasm. Here, we report that InsP6K2 is localized mainly in the cytoplasm of lymphoblast cells from patients with Huntington disease (HD), whereas this enzyme is localized in the nucleus in control lymphoblast cells. The large number of autophagosomes detected in HD lymphoblast cells is consistent with the down-regulation of Akt in response to InsP6K2 activation. Consistent with these observations, the overexpression of InsP6Ks leads to the depletion of Akt phosphorylation and the induction of cell death. These results suggest that InsP6K2 activation is associated with the pathogenesis of HD. PMID:21652713

Nagata, Eiichiro; Saiardi, Adolfo; Tsukamoto, Hideo; Okada, Yoshinori; Itoh, Yoshiko; Satoh, Tadayuki; Itoh, Johbu; Margolis, Russell L.; Takizawa, Shunya; Sawa, Akira; Takagi, Shigeharu

2011-01-01

315

Luteolin Reduces Alzheimer's Disease Pathologies Induced by Traumatic Brain Injury  

PubMed Central

Traumatic brain injury (TBI) occurs in response to an acute insult to the head and is recognized as a major risk factor for Alzheimer’s disease (AD). Indeed, recent studies have suggested a pathological overlap between TBI and AD, with both conditions exhibiting amyloid-beta (A?) deposits, tauopathy, and neuroinflammation. Additional studies involving animal models of AD indicate that some AD-related genotypic determinants may be critical factors enhancing temporal and phenotypic symptoms of TBI. Thus in the present study, we examined sub-acute effects of moderate TBI delivered by a gas-driven shock tube device in A? depositing Tg2576 mice. Three days later, significant increases in b-amyloid deposition, glycogen synthase-3 (GSK-3) activation, phospho-tau, and pro-inflammatory cytokines were observed. Importantly, peripheral treatment with the naturally occurring flavonoid, luteolin, significantly abolished these accelerated pathologies. This study lays the groundwork for a safe and natural compound that could prevent or treat TBI with minimal or no deleterious side effects in combat personnel and others at risk or who have experienced TBI. PMID:24413756

Sawmiller, Darrell; Li, Song; Shahaduzzaman, Md; Smith, Adam J.; Obregon, Demian; Giunta, Brian; Borlongan, Cesar V.; Sanberg, Paul R.; Tan, Jun

2014-01-01

316

Luteolin reduces Alzheimer's disease pathologies induced by traumatic brain injury.  

PubMed

Traumatic brain injury (TBI) occurs in response to an acute insult to the head and is recognized as a major risk factor for Alzheimer's disease (AD). Indeed, recent studies have suggested a pathological overlap between TBI and AD, with both conditions exhibiting amyloid-beta (A?) deposits, tauopathy, and neuroinflammation. Additional studies involving animal models of AD indicate that some AD-related genotypic determinants may be critical factors enhancing temporal and phenotypic symptoms of TBI. Thus in the present study, we examined sub-acute effects of moderate TBI delivered by a gas-driven shock tube device in A? depositing Tg2576 mice. Three days later, significant increases in b-amyloid deposition, glycogen synthase-3 (GSK-3) activation, phospho-tau, and pro-inflammatory cytokines were observed. Importantly, peripheral treatment with the naturally occurring flavonoid, luteolin, significantly abolished these accelerated pathologies. This study lays the groundwork for a safe and natural compound that could prevent or treat TBI with minimal or no deleterious side effects in combat personnel and others at risk or who have experienced TBI. PMID:24413756

Sawmiller, Darrell; Li, Song; Shahaduzzaman, Md; Smith, Adam J; Obregon, Demian; Giunta, Brian; Borlongan, Cesar V; Sanberg, Paul R; Tan, Jun

2014-01-01

317

Resolution of inflammation in obesity-induced liver disease  

PubMed Central

Low-grade inflammation in adipose tissue is recognized as a critical event in the development of obesity-related co-morbidities. This chronic inflammation is powerfully augmented through the infiltration of macrophages, which together with adipocytes, perpetuate a vicious cycle of inflammatory cell recruitment and secretion of free fatty acids and deleterious adipokines that predispose to greater incidence of metabolic complications. In the last decade, many factors have been identified to contribute to mounting unresolved inflammation in obese adipose tissue. Among them, pro-inflammatory lipid mediators (i.e., leukotrienes) derived from the omega-6 polyunsaturated arachidonic acid have been shown to play a prominent role. Of note, the same lipid mediators that initially trigger the inflammatory response also signal its termination by stimulating the formation of anti-inflammatory signals. Resolvins and protectins derived from the omega-3 polyunsaturated docosahexaenoic and eicosapentaenoic acids have emerged as a representative family of this novel class of autacoids with dual anti-inflammatory and pro-resolving properties that act as “stop-signals” of the inflammatory response. This review discusses the participation of these endogenous autacoids in the resolution of adipose tissue inflammation, with a special emphasis in the amelioration of obesity-related metabolic dysfunctions, namely insulin resistance and non-alcoholic fatty liver disease. PMID:22934096

Rius, Bibiana; López-Vicario, Cristina; González-Périz, Ana; Morán-Salvador, Eva; García-Alonso, Verónica; Clária, Joan; Titos, Esther

2012-01-01

318

Modeling pathogenesis of Huntington's disease with inducible neuroprogenitor cells.  

PubMed

Huntington's disease (HD) is caused by an abnormal expansion of CAG trinucleotide repeats encoding polyglutamine (polyQ) in the first exon of the huntingtin (htt) gene. Despite considerable efforts, the pathogenesis of HD remains largely unclear due to a paucity of models that can reliably reproduce the pathological characteristics of HD. Here, we report a neuronal cell model of HD using the previously established tetracycline regulated rat neuroprogenitor cell line, HC2S2. Stable expression of enhanced green fluorescence protein tagged htt exon 1 (referred to as 28Q and 74Q, respectively) in the HC2S2 cells did not affect rapid neuronal differentiation. However, compared to the cells expressing wild type htt, the cell line expressing mutant htt showed an increase in time-dependent cell death and neuritic degeneration, and displayed increased vulnerability to oxidative stress. Increased protein aggregation during the process of neuronal aging or when the cells were exposed to oxidative stress reagents was detected in the cell line expressing 74Q but not in its counterpart. These results suggest that the neuroprogenitor cell lines mimic the major neuropathological characteristics of HD and may provide a useful tool for studying the neuropathogenesis of HD and for high throughput screening of therapeutic compounds. PMID:21452052

Dong, G; Ferguson, J M; Duling, A J; Nicholas, R G; Zhang, D; Rezvani, K; Fang, S; Monteiro, M J; Li, S; Li, X-J; Wang, H

2011-07-01

319

Effects of ultrafine particles-induced oxidative stress on Clara cells in allergic lung inflammation  

PubMed Central

Background Clara cell protein (CC16), the main secretory product of bronchiolar Clara cells, plays an important protective role in the respiratory tract against oxidative stress and inflammation. The purpose of the study was to investigate the role of elemental carbon ultrafine particles (EC-UFP)-induced oxidative stress on Clara cells and CC16 in a mouse model of allergic lung inflammation. Methods Ovalbumin (OVA)-sensitized mice were exposed to EC-UFP (507 ?g/m3 for 24 h) or filtered air immediately prior to allergen challenge and systemically treated with N-acetylcysteine (NAC) or vehicle prior and during EC-UFP inhalation. CC16 was measured up to one week after allergen challenge in bronchoalveolar lavage fluid (BALF) and in serum. The relative expression of CC16 and TNF-? mRNA were measured in lung homogenates. A morphometrical analysis of mucus hypersecretion and electron microscopy served to investigate goblet cell metaplasia and Clara cell morphological alterations. Results In non sensitized mice EC-UFP inhalation caused alterations in CC16 concentration, both at protein and mRNA level, and induced Clara cell hyperplasia. In sensitized mice, inhalation of EC-UFP prior to OVA challenge caused most significant alterations of BALF and serum CC16 concentration, BALF total protein and TNF-? relative expression compared to relevant controls; their Clara cells displayed the strongest morphological alterations and strongest goblet cell metaplasia occurred in the small airways. NAC strongly reduced both functional and morphological alterations of Clara cells. Conclusion Our findings demonstrate that oxidative stress plays an important role in EC-UFP-induced augmentation of functional and morphological alterations of Clara cells in allergic lung inflammation. PMID:20420656

2010-01-01

320

Fructose Induced Endotoxemia in Pediatric Nonalcoholic Fatty Liver Disease  

PubMed Central

In preclinical studies of fructose-induced NAFLD, endotoxin appears to play an important role. We retrospectively examined samples from three pediatric cohorts (1) to investigate whether endotoxemia is associated with the presence of hepatic steatosis; (2) to evaluate postprandial endotoxin levels in response to fructose beverage in an acute 24-hour feeding challenge, and (3) to determine the change of fasting endotoxin amounts in a 4-week randomized controlled trial comparing fructose to glucose beverages in NAFLD. We found that adolescents with hepatic steatosis had elevated endotoxin levels compared to obese controls and that the endotoxin level correlated with insulin resistance and several inflammatory cytokines. In a 24-hour feeding study, endotoxin levels in NAFLD adolescents increased after fructose beverages (consumed with meals) as compared to healthy children. Similarly, endotoxin was significantly increased after adolescents consumed fructose beverages for 2 weeks and remained high although not significantly at 4 weeks. In conclusion, these data provide support for the concept of low level endotoxemia contributing to pediatric NAFLD and the possible role of fructose in this process. Further studies are needed to determine if manipulation of the microbiome or other methods of endotoxin reduction would be useful as a therapy for pediatric NAFLD. PMID:25328713

Patel, Shivani S.; Sun, Xiaoyan; Song, Ming; Mannery, Yanci O.; McClain, Craig J.; Vos, Miriam B.

2014-01-01

321

Fructose induced endotoxemia in pediatric nonalcoholic Fatty liver disease.  

PubMed

In preclinical studies of fructose-induced NAFLD, endotoxin appears to play an important role. We retrospectively examined samples from three pediatric cohorts (1) to investigate whether endotoxemia is associated with the presence of hepatic steatosis; (2) to evaluate postprandial endotoxin levels in response to fructose beverage in an acute 24-hour feeding challenge, and (3) to determine the change of fasting endotoxin amounts in a 4-week randomized controlled trial comparing fructose to glucose beverages in NAFLD. We found that adolescents with hepatic steatosis had elevated endotoxin levels compared to obese controls and that the endotoxin level correlated with insulin resistance and several inflammatory cytokines. In a 24-hour feeding study, endotoxin levels in NAFLD adolescents increased after fructose beverages (consumed with meals) as compared to healthy children. Similarly, endotoxin was significantly increased after adolescents consumed fructose beverages for 2 weeks and remained high although not significantly at 4 weeks. In conclusion, these data provide support for the concept of low level endotoxemia contributing to pediatric NAFLD and the possible role of fructose in this process. Further studies are needed to determine if manipulation of the microbiome or other methods of endotoxin reduction would be useful as a therapy for pediatric NAFLD. PMID:25328713

Jin, Ran; Willment, Andrew; Patel, Shivani S; Sun, Xiaoyan; Song, Ming; Mannery, Yanci O; Kosters, Astrid; McClain, Craig J; Vos, Miriam B

322

Continuum- and particle-based modeling of shapes and dynamics of red blood cells in health and disease  

PubMed Central

We review recent advances in multiscale modeling of the mechanics of healthy and diseased red blood cells (RBCs), and blood flow in the microcirculation. We cover the traditional continuum-based methods but also particle-based methods used to model both the RBCs and the blood plasma. We highlight examples of successful simulations of blood flow including malaria and sickle cell anemia. PMID:23230450

Li,, Xuejin; Vlahovska, Petia M.

2012-01-01

323

On-line determination of nanometric and sub-micrometric particle physicochemical characteristics using spectral imaging-aided Laser-Induced Breakdown Spectroscopy coupled with a Scanning Mobility Particle Sizer  

Microsoft Academic Search

Laser-Induced Breakdown Spectroscopy has been employed to detect sodium chloride and metallic particles with sizes ranging from 40 nm up to 1 µm produced by two different particle generators. The Laser-Induced Breakdown Spectroscopy technique combined with a Scanning Mobility Particle Sizer was evaluated as a potential candidate for workplace surveillance in industries producing nanoparticle-based materials. Though research is still currently under way

Tanguy Amodeo; Christophe Dutouquet; Olivier Le Bihan; Michel Attoui; Emeric Frejafon

2009-01-01

324

Swainsonine-induced high mountain disease in calves.  

PubMed

Swainsonine, an indolizidine alkaloid in the locoweeds (certain species of the Astragalus and Oxytropis genera), was fed to young Holstein bull calves in their milk at high elevation (3090 m), and the incidence of high mountain disease (HMD) was compared with locoweed-fed and control calves. Five of 5 calves fed swainsonine and 5 of 5 calves fed fresh Oxytropis sericea showed outward signs of HMD, which included edema under the jaws, throat area and brisket and gross and microscopic lesions of HMD and locoweed poisoning. Grossly there were HMD lesions, including congestion of the liver, right ventricular hypertrophy, and dilatation and excessive fluid in the thoracic and abdominal cavities. Microscopically, the severe centrilobular lesions in the liver, edema of the pulmonary artery, severe edema and/or fibrosis of the roof of the right atrium were suggestive of HMD. The mild to moderate neurovisceral cytoplasmic foamy vacuolation of selected tissues and cerebellar neuroaxonal dystrophy in all calves fed swainsonine and locoweed were indicative of locoweed poisoning. In control calves, 1 of 6 showed equally severe outward, gross, and microscopic lesions of HMD, but none had any lesions indicative of locoweed poisoning. The ratio of right ventricle to left ventricle wall weights were significantly higher (P = 0.033) for the swainsonine-fed calves (1.4) and the locoweed-fed calves (1.3) compared to the controls (0.9). Scores indicating the severity of HMD from observations prior to necropsy were significantly higher for the swainsonine and locoweed-fed calves compared to controls (P = 0.032).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1907051

James, L F; Panter, K E; Broquist, H P; Hartley, W J

1991-06-01

325

Gut microbiome composition and function in experimental colitis during active disease and treatment-induced remission  

PubMed Central

Dysregulated immune responses to gut microbes are central to inflammatory bowel disease (IBD), and gut microbial activity can fuel chronic inflammation. Examining how IBD-directed therapies influence gut microbiomes may identify microbial community features integral to mitigating disease and maintaining health. However, IBD patients often receive multiple treatments during disease flares, confounding such analyses. Preclinical models of IBD with well-defined disease courses and opportunities for controlled treatment exposures provide a valuable solution. Here, we surveyed the gut microbiome of the T-bet?/? Rag2?/? mouse model of colitis during active disease and treatment-induced remission. Microbial features modified among these conditions included altered potential for carbohydrate and energy metabolism and bacterial pathogenesis, specifically cell motility and signal transduction pathways. We also observed an increased capacity for xenobiotics metabolism, including benzoate degradation, a pathway linking host adrenergic stress with enhanced bacterial virulence, and found decreased levels of fecal dopamine in active colitis. When transferred to gnotobiotic mice, gut microbiomes from mice with active disease versus treatment-induced remission elicited varying degrees of colitis. Thus, our study provides insight into specific microbial clades and pathways associated with health, active disease and treatment interventions in a mouse model of colitis. PMID:24500617

Rooks, Michelle G; Veiga, Patrick; Wardwell-Scott, Leslie H; Tickle, Timothy; Segata, Nicola; Michaud, Monia; Gallini, Carey Ann; Beal, Chloe; van Hylckama-Vlieg, Johan ET; Ballal, Sonia A; Morgan, Xochitl C; Glickman, Jonathan N; Gevers, Dirk; Huttenhower, Curtis; Garrett, Wendy S

2014-01-01

326

Gut microbiome composition and function in experimental colitis during active disease and treatment-induced remission.  

PubMed

Dysregulated immune responses to gut microbes are central to inflammatory bowel disease (IBD), and gut microbial activity can fuel chronic inflammation. Examining how IBD-directed therapies influence gut microbiomes may identify microbial community features integral to mitigating disease and maintaining health. However, IBD patients often receive multiple treatments during disease flares, confounding such analyses. Preclinical models of IBD with well-defined disease courses and opportunities for controlled treatment exposures provide a valuable solution. Here, we surveyed the gut microbiome of the T-bet(-/-) Rag2(-/-) mouse model of colitis during active disease and treatment-induced remission. Microbial features modified among these conditions included altered potential for carbohydrate and energy metabolism and bacterial pathogenesis, specifically cell motility and signal transduction pathways. We also observed an increased capacity for xenobiotics metabolism, including benzoate degradation, a pathway linking host adrenergic stress with enhanced bacterial virulence, and found decreased levels of fecal dopamine in active colitis. When transferred to gnotobiotic mice, gut microbiomes from mice with active disease versus treatment-induced remission elicited varying degrees of colitis. Thus, our study provides insight into specific microbial clades and pathways associated with health, active disease and treatment interventions in a mouse model of colitis. PMID:24500617

Rooks, Michelle G; Veiga, Patrick; Wardwell-Scott, Leslie H; Tickle, Timothy; Segata, Nicola; Michaud, Monia; Gallini, Carey Ann; Beal, Chloé; van Hylckama-Vlieg, Johan E T; Ballal, Sonia A; Morgan, Xochitl C; Glickman, Jonathan N; Gevers, Dirk; Huttenhower, Curtis; Garrett, Wendy S

2014-07-01

327

New lessons learned from disease modeling with induced Pluripotent Stem Cells  

PubMed Central

Cellular reprogramming and generation of induced pluripotent stem cells (iPSCs) from adult cell types has enabled the creation of patient-specific stem cells for use in disease modeling. To date, many iPSC lines have been generated from a variety of disorders, which have then been differentiated into disease-relevant cell types. When a disease-specific phenotype is detectable in such differentiated cells, the reprogramming technology provides a new opportunity to identify aberrant disease-associated pathways and drugs that can block them. Here, we highlight recent progress as well as limitations in the use of iPSCs to recapitulate disease phenotypes and to screen for therapeutics in vitro. PMID:22749051

Onder, Tamer T.; Daley, George Q.

2012-01-01

328

Human adjuvant disease: remission of silicone induced autoimmune disease after explanation of breast augmentation  

Microsoft Academic Search

Autoimmune diseases following silicone or paraffin implantation are rarely encountered complications of plastic surgery. A 42 year old woman is presented who developed clinical and immunological features of systemic lupus erythematosus 11 years after silicone augmentation. After explanation antinuclear antibody titres decreased from 1\\/1280 to 1\\/160, C4 complement fraction and the previously raised angiotensin converting enzyme normalised in step with

W kaiser; G Biesenbach; U Stuby; P Grafinger; J Zazgornik

1990-01-01

329

Mechanisms of action of inhaled fibers, particles and nanoparticles in lung and cardiovascular diseases  

Microsoft Academic Search

BACKGROUND: A symposium on the mechanisms of action of inhaled airborne particulate matter (PM), pathogenic particles and fibers such as silica and asbestos, and nanomaterials, defined as synthetic particles or fibers less than 100 nm in diameter, was held on October 27 and 28, 2005, at the Environmental Protection Agency (EPA) Conference Center in Research Triangle Park, North Carolina. The

Brooke T Mossman; Paul J Borm; Vincent Castranova; Daniel L Costa; Kenneth Donaldson; Steven R Kleeberger

2007-01-01

330

Application of human induced pluripotent stem cells for modeling and treating neurodegenerative diseases.  

PubMed

The advent of human induced pluripotent stem cells (hiPSCs), reprogrammed in vitro from both healthy and disease-state human somatic cells, has triggered an enormous global research effort to realize personalized regenerative medicine for numerous degenerative conditions. hiPSCs have been generated from cells of many tissue types and can be differentiated in vitro to most somatic lineages, not only for the establishment of disease models that can be utilized as novel drug screening platforms and to study the molecular and cellular processes leading to degeneration, but also for the in vivo cell-based repair or modulation of a patient's disease profile. hiPSCs derived from patients with the neurodegenerative diseases amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease and multiple sclerosis have been successfully differentiated in vitro into disease-relevant cell types, including motor neurons, dopaminergic neurons and oligodendrocytes. However, the generation of functional iPSC-derived neural cells that are capable of engraftment in humans and the identification of robust disease phenotypes for modeling neurodegeneration still require several key challenges to be addressed. Here, we discuss these challenges and summarize recent progress toward the application of iPSC technology for these four common neurodegenerative diseases. PMID:24815224

Payne, Natalie L; Sylvain, Aude; O'Brien, Carmel; Herszfeld, Daniella; Sun, Guizhi; Bernard, Claude C A

2015-01-25

331

AN EPIZOOTIC OF ADENOVIRUS-INDUCED HEMORRHAGIC DISEASE IN CAPTIVE BLACK-TAILED DEER (ODOCOILEUS HEMIONUS)  

Microsoft Academic Search

Ten fawns and four adult black-tailed deer (Odocoileus hemionus) in a captive herd died as a result of adenovirus-induced hemorrhagic disease. Acute, systemic infections were characterized by hemorrhagic enteropathy, pulmonary edema, and occasional ulceration of the upper alimentary tract. Localized infections were limited to the upper alimentary tract and included stomatitis, pharyngitis, mandibular osteomyelitis, and rumenitis. In deer with acute,

Walter M. Boyce; Leslie W. Woods; M. Kevin Keel; N. James MacLachlan; Charles O. Porter; Howard D. Lehmkuhl

332

SPONTANEOUSLY HYPERTENSIVE RATS ARE SUSCEPTIBLE TO AIRWAY DISEASE INDUCED BY SULFUR DIOXIDE  

EPA Science Inventory

Rodent models of chronic pulmonary diseases induced by sulfur dioxide (SO2), elastase or tobacco smoke have limited utility because of their lack of chronicity of inflammation, and they demonstrate limited sensitivity to a given experimental manipulation. We hypothesized that dis...

333

New Insights into the Pathogenesis of Alcohol-Induced ER Stress and Liver Diseases  

PubMed Central

Alcohol-induced liver disease increasingly contributes to human mortality worldwide. Alcohol-induced endoplasmic reticulum (ER) stress and disruption of cellular protein homeostasis have recently been established as a significant mechanism contributing to liver diseases. The alcohol-induced ER stress occurs not only in cultured hepatocytes but also? in vivo??in the livers of several species including mouse, rat, minipigs, zebrafish, and humans. Identified causes for the ER stress include acetaldehyde, oxidative stress, impaired one carbon metabolism, toxic lipid species, insulin resistance, disrupted calcium homeostasis, and aberrant epigenetic modifications. Importance of each of the causes in alcohol-induced liver injury depends on doses, duration and patterns of alcohol exposure, genetic disposition, environmental factors, cross-talks with other pathogenic pathways, and stages of liver disease. The ER stress may occur more or less all the time during alcohol consumption, which interferes with hepatic protein homeostasis, proliferation, and cell cycle progression promoting development of advanced liver diseases. Emerging evidence indicates that long-term alcohol consumption and ER stress may directly be involved in hepatocellular carcinogenesis (HCC). Dissecting ER stress signaling pathways leading to tumorigenesis will uncover potential therapeutic targets for intervention and treatment of human alcoholics with liver cancer. PMID:24868470

2014-01-01

334

EFFECTS OF SYSTEMIC NEUTROPHIL DEPLETION ON LPS-INDUCED AIRWAY DISEASE  

EPA Science Inventory

Effects of Systemic Neutrophil Depletion on LPS-induced Airway Disease Jordan D. Savov, Stephen H. Gavett*, David M. Brass, Daniel L. Costa*, David A. Schwartz Pulmonary and Critical Care Division, Dept of Medicine ? Duke University Medical Center * National Health and E...

335

Autophagy induced by Alexander disease-mutant GFAP accumulation is regulated by p38/MAPK  

E-print Network

Autophagy induced by Alexander disease-mutant GFAP accumulation is regulated by p38/MAPK and m of autophagy. Our study suggests that AxD mutant GFAP accumulation stimulates autophagy, in a manner regulated by p38 MAPK and mTOR signaling pathways. Autophagy, in turn, serves as a mechanism to reduce GFAP

Sulzer, David

336

A proteomic analysis of MCLR-induced neurotoxicity: implications for Alzheimer's disease.  

PubMed

Cyanobacteria-derived microcystin-leucine-arginine (MCLR), commonly characterized as a hepatotoxin, has recently been found to show neurotoxicity, but the exact mechanism is still unknown. To further our understanding of the neurotoxic effects of MCLR and the mechanisms behind it, we used two-dimensional gel electrophoresis and mass spectrometry analysis to identify global protein profiles associated with MCLR-induced neurotoxicity. MCLR-treated hippocampi showed alterations in proteins involved in cytoskeleton, neurodegenerative disease, oxidative stress, apoptosis, and energy metabolism. After validation by Western blot and quantitative real-time PCR, the expressions of three proteins related to neurodegenerative disease, septin 5, ?-internexin, and ?-synuclein, were identified to be altered by MCLR exposure. Based on our proteomic analysis that MCLR toxicity might be linked to neurodegeneration, we examined the activity of serine/threonine-specific protein phosphatases (PPs), which are markers of neurodegenerative disease. MCLR was found to induce inhibition of PPs and abnormal hyperphosphorylation of the neuronal microtubule-associated protein tau. This was found to lead to impairment of learning and memory, accompanied by severe histological damage and neuronal apoptosis in the hippocampal CA1 regions of rats. Our results support the hypothesis that MCLR could induce neurotoxic effects, the reason for which could be attributed to the disruption of the cytoskeleton, oxidative stress, and inhibition of PPs in the hippocampus. Moreover, MCLR was found to induce tau hyperphosphorylation, spatial memory impairment, neuronal degenerative changes, and apoptosis, suggesting that this cyanotoxin may contribute to Alzheimer's disease in humans. PMID:22430071

Li, Guangyu; Cai, Fei; Yan, Wei; Li, Cairong; Wang, Jianghua

2012-06-01

337

Exercise-induced Signals for Vascular Endothelial Adaptations: Implications for Cardiovascular Disease  

PubMed Central

This article reviews recent advances in our understanding of hemodynamic signals, external/compressive forces, and circulating factors that mediate exercise training-induced vascular adaptations, with particular attention to the roles of these signals in prevention and treatment of endothelial dysfunction and cardiovascular (CV) diseases. PMID:22844545

Jenkins, Nathan T.; Martin, Jeffrey S.; Laughlin, M. Harold; Padilla, Jaume

2012-01-01

338

Protective immune response of chickens against Newcastle disease, induced by the intranasal vaccination with inactivated virus  

Microsoft Academic Search

Intranasal vaccination of chickens with inactivated Newcastle disease virus (NDV) induced both local and systemic antibody responses, resulting in protection against intranasal challenge with a lethal dose of a virulent NDV strain. The immune response was enhanced by the use of cholera toxin B subunit (CTB) as an adjuvant and only small amounts of the challenge virus were recovered from

Ayato Takada; Hiroshi Kida

1996-01-01

339

Protection of the Reproductive Tract of Young Chicks by Newcastle Disease Virus-induced Haemagglutinationinhibition Antibodies  

Microsoft Academic Search

The present study was conducted to assess the haemagglutination-inhibition (HI) titres required to protect the chicken reproductive tract against direct damage caused by Newcastle disease virus (NDV). Precociously induced oviduct and uterus by oestrogen treatment of young chicks were used to assess the damage or protection against the damage by analysis of ciliostasis or histopathological lesions. Unvaccinated day-old female white

J. Raghul; G. Dhinakar Raj; B. Murali Manohar; C. Balachandran

2006-01-01

340

Theiler's murine encephalomyelitis virus-induced cardiac and skeletal muscle disease.  

PubMed Central

The DA strain of Theiler's murine encephalomyelitis virus, a member of the cardiovirus genus of picornaviruses, induces a restricted and persistent infection associated with a demyelinating process following intracerebral inoculation of mice; both virus infection and the immune response are believed to contribute to the late white matter disease. We now report that intraperitoneal inoculation with DA produces an acute myositis that progresses to a chronic inflammatory muscle disease in CD-1 mice as well as several inbred mouse strains. Some mouse strains also develop central nervous system white matter disease and a focal myocarditis. Infectious virus in skeletal muscle falls to undetectable levels 3 weeks postinoculation (p.i.), although viral genome persists for at least 12 weeks p.i., the longest period of observation. Severe combined immunodeficient animals have evidence of muscle pathology as long as 5 weeks p.i., suggesting that DA virus is capable of inducing chronic muscle disease in the absence of an immune response. The presence in immunocompetent mice, however, of prominent muscle inflammation in the absence of infectious virus suggests that the immune system also contributes to the pathology. T lymphocytes are the predominant cell type infiltrating the skeletal muscle during the chronic disease. This murine model may further our understanding of virus-induced chronic myositis and help to clarify the pathogenesis of human inflammatory myopathies. PMID:8971022

Gomez, R M; Rinehart, J E; Wollmann, R; Roos, R P

1996-01-01

341

Concentrated ambient fine particles and not ozone induce a systemic interleukin-6 response in humans.  

PubMed

Epidemiological studies have established significant associations between ambient pollutants, including fine particulate matter (PM(2.5)) and ozone (O(3)), and cardiopulmonary morbidity and mortality. One mechanism that has been proposed is a pulmonary/systemic inflammatory response. Although controlled human exposure studies have examined the independent inflammatory responses of PM(2.5) and O(3), no studies have previously examined their joint effects. The study objective was to examine the independent and combined associations between ambient PM(2.5) and O(3) and acute respiratory/inflammatory responses. Using their concentrated ambient particle (CAP) facility for PM(2.5), the authors studied 10 mild asthmatic and 13 nonasthmatic individuals. The 2-h exposures included CAP (range 48-199 microg/m(3)) and filtered air (FA), with/without O(3) (120 ppb), in a randomized block design. Response measures included pulmonary function and inflammatory indices in induced sputum (interleukin [IL]-6, cytology) and blood (IL-6, tumor necrosis factor [TNF]-alpha) measured before and after exposures. Three hours post exposure, there was an increase in blood levels of IL-6, but only after CAP alone exposures; the IL-6 increase was associated with increasing PM(2.5) mass concentration (p = .005). Some individuals switched to shallow breathing during CAP+O(3), possibly accounting for an attenuation of the resultant blood IL-6 response. Asthmatic and nonasthmatic responses were similar. There were no adverse changes in pulmonary function or other inflammatory measures. The study demonstrated an acute IL-6 response to PM(2.5), providing evidence to support the epidemiological findings of associations between ambient levels of particles and cardiopulmonary morbidity and mortality. PMID:20088738

Urch, Bruce; Speck, Mary; Corey, Paul; Wasserstein, David; Manno, Michael; Lukic, Karl Z; Brook, Jeffrey R; Liu, Ling; Coull, Brent; Schwartz, Joel; Gold, Diane R; Silverman, Frances

2010-02-01

342

Calcineurin/NFAT pathway mediates wear particle-induced TNF-? release and osteoclastogenesis from mice bone marrow macrophages in vitro  

PubMed Central

Aim: To investigate the roles of the calcineurin/nuclear factor of activated T cells (NFAT) pathway in regulation of wear particles-induced cytokine release and osteoclastogenesis from mouse bone marrow macrophages in vitro. Methods: Osteoclasts were induced from mouse bone marrow macrophages (BMMs) in the presence of 100 ng/mL receptor activator of NF-?B ligand (RANKL). Acridine orange staining and MTT assay were used to detect the cell viability. Osteoclastogenesis was determined using TRAP staining and RT-PCR. Bone pit resorption assay was used to examine osteoclast phenotype. The expression and cellular localization of NFATc1 were examined using RT-PCR and immunofluorescent staining. The production of TNF? was analyzed with ELISA. Results: Titanium (Ti) or polymethylmethacrylate (PMMA) particles (0.1 mg/mL) did not significantly change the viability of BMMs, but twice increased the differentiation of BMMs into mature osteoclasts, and markedly increased TNF-? production. The TNF-? level in the PMMA group was significantly higher than in the Ti group (96 h). The expression of NFATc1 was found in BMMs in the presence of the wear particles and RANKL. In bone pit resorption assay, the wear particles significantly increased the resorption area and total number of resorption pits in BMMs-seeded ivory slices. Addition of 11R-VIVIT peptide (a specific inhibitor of calcineurin-mediated NFAT activation, 2.0 ?mol/L) did not significantly affect the viability of BMMs, but abolished almost all the wear particle-induced alterations in BMMs. Furthermore, VIVIT reduced TNF-? production much more efficiently in the PMMA group than in the Ti group (96 h). Conclusion: Calcineurin/NFAT pathway mediates wear particles-induced TNF-? release and osteoclastogenesis from BMMs. Blockade of this signaling pathway with VIVIT may provide a promising therapeutic modality for the treatment of periprosthetic osteolysis. PMID:24056707

Liu, Feng-xiang; Wu, Chuan-long; Zhu, Zhen-an; Li, Mao-qiang; Mao, Yuan-qing; Liu, Ming; Wang, Xiao-qing; Yu, De-gang; Tang, Ting-ting

2013-01-01

343

Newcastle disease virus-like particles as a platform for the development of vaccines for human and agricultural pathogens  

PubMed Central

Vaccination is the single most effective way to control viral diseases. However, many currently used vaccines have safety concerns, efficacy issues or production problems. For other viral pathogens, classic approaches to vaccine development have, thus far, been unsuccessful. Virus-like particles (VLPs) are increasingly being considered as vaccine candidates because they offer significant advantages over many currently used vaccines or developing vaccine technologies. VLPs formed with structural proteins of Newcastle disease virus, an avian paramyxovirus, are a potential vaccine candidate for Newcastle disease in poultry. More importantly, these VLPs are a novel, uniquely versatile VLP platform for the rapid construction of effective vaccine candidates for many human pathogens, including genetically complex viruses and viruses for which no vaccines currently exist. PMID:21339837

Morrison, Trudy G

2011-01-01

344

Effects of heavy particle irradiation and diet on amphetamine- and lithium chloride-induced taste avoidance learning in rats  

NASA Technical Reports Server (NTRS)

Rats were maintained on diets containing either 2% blueberry or strawberry extract or a control diet for 8 weeks prior to being exposed to 1.5 Gy of 56Fe particles in the Alternating Gradient Synchrotron at Brookhaven National Laboratory. Three days following irradiation, the rats were tested for the effects of irradiation on the acquisition of an amphetamine- or lithium chloride-induced (LiCl) conditioned taste avoidance (CTA). The rats maintained on the control diet failed to show the acquisition of a CTA following injection of amphetamine. In contrast, the rats maintained on antioxidant diets (strawberry or blueberry extract) continued to show the development of an amphetamine-induced CTA following exposure to 56Fe particles. Neither irradiation nor diet had an effect on the acquisition of a LiCl-induced CTA. The results are interpreted as indicating that oxidative stress following exposure to 56Fe particles may be responsible for the disruption of the dopamine-mediated amphetamine-induced CTA in rats fed control diets; and that a reduction in oxidative stress produced by the antioxidant diets functions to reinstate the dopamine-mediated CTA. The failure of either irradiation or diet to influence LiCl-induced responding suggests that oxidative stress may not be involved in CTA learning following injection of LiCl.

Rabin, Bernard M.; Shukitt-Hale, Barbara; Szprengiel, Aleksandra; Joseph, James A.

2002-01-01

345

Human-induced pluripotent stem cells pave the road for a better understanding of motor neuron disease.  

PubMed

While motor neuron diseases are currently incurable, induced pluripotent stem cell research has uncovered some disease-relevant phenotypes. We will discuss strategies to model different aspects of motor neuron disease and the specific neurons involved in the disease. We will then describe recent progress to investigate common forms of motor neuron disease: amyotrophic lateral sclerosis, hereditary spastic paraplegia and spinal muscular atrophy. PMID:24821704

Winner, Beate; Marchetto, Maria C; Winkler, Jürgen; Gage, Fred H

2014-09-15

346

Effect of particle size on salt-induced diffusiophoresis compared to Brownian mobility.  

PubMed

For ternary polymer-salt-water systems at low polymer concentration (0.5%, w/w), we have experimentally investigated the effect of polymer size on polymer diffusiophoresis (i.e., polymer migration induced by a salt concentration gradient) and salt osmotic diffusion (i.e., salt migration induced by a polymer concentration gradient). Specifically, Rayleigh interferometry was employed to measure ternary diffusion coefficients for aqueous solutions of poly(ethylene glycol) (PEG) and KCl at 25 °C. Our investigation focused on four polymer molecular masses (from 10 to 100 kg mol(-1)) and two salt concentrations (0.25 and 0.50 M). To describe and examine our experimental results, we introduced a normalized diffusiophoresis coefficient as the ratio of polymer diffusiophoresis to polymer Brownian mobility. This coefficient was found to increase with polymer molecular mass, thereby demonstrating that the relative importance of polymer diffusiophoresis compared to its intrinsic Brownian mobility increases with particle size. The observed behavior was linked to preferential hydration (water thermodynamic excess) and hydration (bound water) of the macromolecule. The ratio of salt osmotic diffusion to binary salt-water diffusion approximately describes the nonuniform spatial distribution of salt along a static polymer concentration gradient at equilibrium. The significance of polymer diffusiophoresis, especially at high PEG molecular mass, was examined by considering a steady-state diffusion problem showing that salt concentration gradients can produce large enhancements and depletions of polymer concentration. This work is valuable for understanding and modeling the effect of salt concentration gradients on diffusion-based transport of polymers with applications to interfacial processes. PMID:24758490

McAfee, Michele S; Annunziata, Onofrio

2014-05-01

347

Results and perspectives of the investigation of traditional and thermal stress induced thermophoresis of particles in gas in microgravity  

NASA Astrophysics Data System (ADS)

Thermophoretic motion of particles suspended in a gas has been a subject of extensive theoretical and experimental investigations for many years because of its wide spread in nature, significance for fundamental and applied aerosol physic. Negative thermophoresis, i.e. solid particle motion towards hotter region in a gas and not as usually from hotter region, was predicted more than 40 years ago and remains an unsolved problem for a choice between different models treating main driving mechanisms -- thermal slip and thermal stress induced gas motion. For a problem of negative thermophoresis, we present experimental evidences in favor of the latter mechanism based on direct observation of particle motion at microgravity; Knudsen particle number 2\\cdot 10(-3) (Kn being the ratio of the molecular mean free path to the particle size); particle-to-gas heat conductivity ratios 2\\cdot 10(4) for copper solid particles and 1.8 for glass bubbles. For both types of particles the experimental results fit well the gas kinetic model of Beresnev and Chernyak [1]. We present characteristics of a set-up and procedures that are able to provide sufficient accuracy and volume of experimental data for testing any model of particle thermophoresis. High quality microgravity is a necessity for such investigations. The short duration microgravity of drop towers suits well this requirement. The sign and value of the thermophoretic force strongly depends on the Knudsen number, particle-to-gas heat conductivity ratio and accommodation coefficients, all of which vary within several decimal orders of magnitude. In order to make crucial conclusions on the choice of the adequate model, there should be hundreds of short duration microgravity experiments. The European Space Agency scientific project Interaction in Cosmic and Atmospheric Particle Systems (ICAPS) [2] planned for the International Space Station, provides complementary opportunities for the investigation of thermophoresis at large and very large Knudsen numbers for single particles and large clusters of particles under wide range of experimental parameters, i.e. different particle sizes, shapes, materials; different properties of gases; several types of additional forces and their time-space variation. ESA PRODEX Program, Belgian Federal Science Policy Office and Bremen Drop Tower Operation and Service Company ZARM FABmbH (Germany) are greatly acknowledged for their support. [1] Beresnev S., Chernyak V. Thermophoresis of a spherical particle in a rarefied gas: Numerical analysis based on the model kinetic equations // Phys. Fluids. 1995. V.7. P.1743. [2] Blum, J. et al. "Dust in Space", Europhysicsnews, Vol. 39, pp. 27-29, 2008.

Vedernikov, Andrei; Balapanov, Daniyar; Beresnev, Sergey; Queeckers, Patrick

348

A Review on Chemical-Induced Inflammatory Bowel Disease Models in Rodents  

PubMed Central

Ulcerative colitis and Crohn's disease are a set of chronic, idiopathic, immunological and relapsing inflammatory disorders of the gastrointestinal tract referred to as inflammatory bowel disorder (IBD). Although the etiological factors involved in the perpetuation of IBD remain uncertain, development of various animal models provides new insights to unveil the onset and the progression of IBD. Various chemical-induced colitis models are widely used on laboratory scale. Furthermore, these models closely mimic morphological, histopathological and symptomatical features of human IBD. Among the chemical-induced colitis models, trinitrobenzene sulfonic acid (TNBS)-induced colitis, oxazolone induced-colitis and dextran sulphate sodium (DSS)-induced colitis models are most widely used. TNBS elicits Th-1 driven immune response, whereas oxazolone predominantly exhibits immune response of Th-2 phenotype. DSS-induced colitis model also induces changes in Th-1/Th-2 cytokine profile. The present review discusses the methodology and rationale of using various chemical-induced colitis models for evaluating the pathogenesis of IBD. PMID:25177159

Randhawa, Puneet Kaur; Singh, Kavinder; Singh, Nirmal

2014-01-01

349

Particle-Induced X-Ray Emission (PIXE) Of Silicate Coatings On High Impact Resistance Polycarbonates  

NASA Astrophysics Data System (ADS)

Particle-Induced X-ray Emission (PIXE) analysis was employed to characterize hydroxypropyl methylcellulose (HPMC) C32H60O19 polymer film via areal density measurement on silicon-based substrates utilizing the differential PIXE concept, and compared with Rutherford backscattering spectrometry (RBS) results. It is demonstrated in this paper that PIXE and RBS measurements both yield comparable results for areal densities ranging from 1018 atom/cm2 to several 1019 atom/cm2. A collection of techniques including PIXE, RBS, tapping mode atomic force microscopy (TMAFM), and contact angle analysis were used to compute surface free energy, analyze surface topography and roughness parameters, determine surface composition and areal density, and to predict the water affinity and condensation behaviors of silicates and other compounds used for high impact resistance vision ware coatings. The visor surface under study is slightly hydrophilic, with root mean square of surface roughness on the order of one nm, and surface wavelength between 200 nm and 300 nm. Water condensation can be controlled on such surfaces via polymers adsorption. HPMC polymer areal density measurement supports the analysis of the surface water affinity and topography and the subsequent control of condensation behavior. HPMC film between 1018 atom/cm2 and 1019 atom/cm2 was found to effectively alter the water condensation pattern and prevents fogging by forming a wetting layer during condensation.

Xing, Qian; Hart, M. A.; Culbertson, R. J.; Bradley, J. D.; Herbots, N.; Wilkens, Barry J.; Sell, David A.; Watson, Clarizza Fiel

2011-06-01

350

Transition-Edge Sensors for Particle Induced X-ray Emission Measurements  

NASA Astrophysics Data System (ADS)

In this paper we present a new measurement setup, where a transition-edge sensor detector array is used to detect X-rays in particle induced X-ray emission (PIXE) measurements with a 2 MeV proton beam. Transition-edge sensors offer orders of magnitude improvement in energy resolution compared to conventional silicon or germanium detectors, making it possible to recognize spectral lines in materials analysis that have previously been impossible to resolve, and to get chemical information from the elements. Our sensors are cooled to the operation temperature (65 mK) with a cryogen-free adiabatic demagnetization refrigerator, which houses a specially designed X-ray snout that has a vacuum tight window to couple in the radiation. For the best pixel, the measured instrumental energy resolution was 3.06 eV full width at half maximum at 5.9 keV. We discuss the current status of the project, benefits of transition-edge sensors when used in PIXE spectroscopy, and the results from the first measurements.

Palosaari, M. R. J.; Kinnunen, K. M.; Julin, J.; Laitinen, M.; Napari, M.; Sajavaara, T.; Doriese, W. B.; Fowler, J.; Reintsema, C.; Swetz, D.; Schmidt, D.; Ullom, J.; Maasilta, I. J.

2014-08-01

351

FINE AMBIENT AIR PARTICULAR MATTER EXPOSURE INDUCES MOLECULAR ALTERATIONS INDICATIVE OF CARDIOVASCULAR DISEASE PROGRESSION IN ATHEROSCLEROTIC SUSCEPTIBLE MICE  

EPA Science Inventory

Epidemiological, clinical, and toxicological studies have demonstrated that exposure to ambient air particulate matter (PM) can alter cardiovascular function and may influence cardiovascular disease (CVD). It has been shown that exposure to concentrated ambient air particles (CA...

352

Light induced heterogeneous ozone processing on the pesticides adsorbed on silica particles  

NASA Astrophysics Data System (ADS)

In France, in 2010, the sales of pesticides reached 1.8 billion euros for 61 900 tons of active ingredients, positioning France as a first European consumer of pesticides, as reported by the European Crop Protection Association. About 19 million hectares of crops are sprayed annually with pesticides, i.e., 35% of the total surface area of France. This corresponds to an average pesticide dose of 3.2 kg ha-1. The consumption of herbicide and fungicide is favoured in comparison to the use of insecticides in France and the other European countries, as well. The partitioning of pesticides between the gas and particulate phases influences the atmospheric fate of these compounds such as their photo-chemical degradation. There is much uncertainty concerning the behavior of the pesticides in the atmosphere. Especially, there is a gap of knowledge concerning the degradation of the pesticides induced by heterogeneous reactions in absence and especially in presence of solar light. Considering that most of the pesticides currently used are semi-volatile, it is of crucial importance to investigate the heterogeneous reactivity of particulate pesticides with light and with atmospheric oxidants such as ozone and OH radical. The aim of the present work is to evaluate the light induced heterogeneous ozonation of suspended pesticide particles. 8 pesticides (cyprodinil, deltamethrin, difenoconazole, fipronil, oxadiazon, pendimethalin, permethrin and tetraconazole) were chosen for their physico-chemical properties and their concentration levels in the PACA (Région Provence-Alpes-Côte d'Azur) region, France. Silica particles with well-known properties were chosen as model particles of atmospheric relevance. Kinetic rate constants were determined to allow estimate the atmospheric lifetimes relating to ozone. The rate constants were determined as follows: k = (6.6 × 0.2) 10-19, (7.2 × 0.3) 10-19, (5.1 × 0.5) 10-19, (3.9 × 0.3) 10-19 [cm3 molecules-1 s-1] for Cyprodinil, delthamethrine, permethrine and pendimethaline, respectively. Concerning the other four pesticides under study i.e. difenoconazole, fipronil, oxadiazon and tetraconazole the obtained rate constants were extremely slow, < 3.9 10-19 [cm3 molecules-1 s-1]. In addition, we identified the condensed phase products in such heterogeneous reactions of ozone with the particulate pesticides by GC-MS coupled with the derivatization technique. The gas-phase products were followed on-line by PTR-MS-TOF. The obtained results will allow to recognize the impact of the pesticides and their degradation products on the human health, and to make recommendations in order to reduce population exposure to the pesticide plume. The results of this work will contribute to better describe and understand the pollution by phyto-sanitary products on the regional scale, which constitutes a necessary step in the development of environmental strategies. As a result the obtained results will help in the development of future environmental strategies to better understand and control phyto-sanitary product application and human exposure.

Socorro, J.; Désert, M.; Quivet, E.; Gligorovski, S.; Wortham, H.

2013-12-01

353

Integrity of Membrane Lipid Rafts Is Necessary for the Ordered Assembly and Release of Infectious Newcastle Disease Virus Particles  

PubMed Central

Membrane lipid raft domains are thought to be sites of assembly for many enveloped viruses. The roles of both classical lipid rafts and lipid rafts associated with the membrane cytoskeleton in the assembly of Newcastle disease virus (NDV) were investigated. The lipid raft-associated proteins caveolin-1, flotillin-2, and actin were incorporated into virions, while the non-lipid raft-associated transferrin receptor was excluded. Kinetic analyses of the distribution of viral proteins in lipid rafts, as defined by detergent-resistant membranes (DRMs), in non-lipid raft membranes, and in virions showed an accumulation of HN, F, and NP viral proteins in lipid rafts early after synthesis. Subsequently, these proteins exited the DRMs and were recovered quantitatively in purified virions, while levels of these proteins in detergent-soluble cell fractions remained relatively constant. Cholesterol depletion of infected cells drastically altered the association of viral proteins with DRMs and resulted in an enhanced release of virus particles with reduced infectivity. Decreased infectivity was not due to effects on subsequent virus entry, since the extraction of cholesterol from intact virus did not significantly reduce infectivity. Particles released from cholesterol-depleted cells had very heterogeneous densities and altered ratios of NP and glycoproteins, demonstrating structural abnormalities which potentially contributed to their lowered infectivity. Taken together, these results indicate that lipid rafts, including cytoskeleton-associated lipid rafts, are sites of NDV assembly and that these domains are important for ordered assembly and release of infectious Newcastle disease virus particles. PMID:17041223

Laliberte, Jason P.; McGinnes, Lori W.; Peeples, Mark E.; Morrison, Trudy G.

2006-01-01

354

Mathematical modelling of the pathogenesis of multiple myeloma-induced bone disease.  

PubMed

Multiple myeloma (MM) is the second most common haematological malignancy and results in destructive bone lesions. The interaction between MM cells and the bone microenvironment plays an important role in the development of the tumour cells and MM-induced bone disease and forms a 'vicious cycle' of tumour development and bone destruction, intensified by suppression of osteoblast activity and promotion of osteoclast activity. In this paper, a mathematical model is proposed to simulate how the interaction between MM cells and the bone microenvironment facilitates the development of the tumour cells and the resultant bone destruction. It includes both the roles of inhibited osteoblast activity and stimulated osteoclast activity. The model is able to mimic the temporal variation of bone cell concentrations and resultant bone volume after the invasion and then removal of the tumour cells and explains why MM-induced bone lesions rarely heal even after the complete removal of MM cells. The behaviour of the model compares well with published experimental data. The model serves as a first step to understand the development of MM-induced bone disease and could be applied further to evaluate the current therapies against MM-induced bone disease and even suggests new potential therapeutic targets. © 2014 The Authors. International Journal for Numerical Methods in Biomedical Engineering published by John Wiley & Sons Ltd. PMID:24817420

Ji, Bing; Genever, Paul G; Patton, Ronald J; Fagan, Michael J

2014-11-01

355

Emerging mechanistic targets in lung injury induced by combustion-generated particles.  

EPA Science Inventory

ABSTRACT The mechanism for biological effect following pulmonary exposure to combustion-generated particles is incompletely defined. Transient receptor potential (TRP) cation channels were identified as ?particle sensors? in that their activation was coupled with the initiation ...

356

Concentrated Ambient Air Particles Induce Mild Pulmonary Inflammation in Healthy Human Volunteers  

Microsoft Academic Search

We tested the hypothesis that exposure of healthy volunteers to concentrated ambient particles (CAPS) is associated with an influx of inflammatory cells into the lower respiratory tract. Thirty-eight volunteers were exposed to either filtered air or particles concen- trated from the immediate environment of the Environmental Pro- tection Agency (EPA) Human Studies Facility in Chapel Hill, North Carolina. Particle concentrations

ANDREW J. GHIO; CHONG KIM; ROBERT B. DEVLIN

2000-01-01

357

Anti-oxidative and inflammatory responses induced by fly ash particles and carbon black in lung epithelial cells.  

PubMed

Combustion-derived nanoparticles as constituents of ambient particulate matter have been shown to induce adverse health effects due to inhalation. However, the components inducing these effects as well as the biological mechanisms are still not fully understood. The fine fraction of fly ash particles collected from the electrostatic precipitator of a municipal solid waste incinerator was taken as an example for real particles with complex composition released into the atmosphere to study the mechanism of early biological responses of BEAS-2B human lung epithelial cells. The studies include the effects of the water-soluble and -insoluble fractions of the fly ash and the well-studied carbon black nanoparticles were used as a reference. Fly ash induced reactive oxygen species (ROS) and increased the total cellular glutathione (tGSH) content. Carbon black also induced ROS generation; however, in contrast to the fly ash, it decreased the intracellular tGSH. The fly ash-induced oxidative stress was correlated with induction of the anti-oxidant enzyme heme oxygenase-1 and increase of the redox-sensitive transcription factor Nrf2. Carbon black was not able to induce HO-1. ROS generation, tGSH increase and HO-1 induction were only induced by the insoluble fraction of the fly ash, not by the water-soluble fraction. ROS generation and HO-1 induction were markedly inhibited by pre-incubation of the cells with the anti-oxidant N-acetyl cysteine which confirmed the involvement of oxidative stress. Both effects were also reduced by the metal chelator deferoxamine indicating a contribution of bioavailable transition metals. In summary, both fly ash and carbon black induce ROS but only fly ash induced an increase of intracellular tGSH and HO-1 production. Bioavailable transition metals in the solid water-insoluble matrix of the fly ash mostly contribute to the effects. PMID:21626191

Diabaté, Silvia; Bergfeldt, Britta; Plaumann, Diana; Ubel, Caroline; Weiss, Carsten

2011-12-01

358

Violet diode laser-induced chlorophyll fluorescence: a tool for assessing mosaic disease severity in cassava (Manihot esculenta Crantz) cultivars.  

PubMed

Violet diode laser-induced chlorophyll fluorescence was used in agronomical assessment (disease severity and average yield per plant). Because cassava (Manihot esculenta Crantz) is of economic importance, improved cultivars with various levels of affinity for cassava mosaic disease were investigated. Fluorescence data correlated with cassava mosaic disease severity levels and with the average yield per plant. PMID:22519123

Anderson, Benjamin; Eghan, Moses J; Asare-Bediako, Elvis; Buah-Bassuah, Paul K

2012-01-01

359

Oxidative stress-induced signaling pathways implicated in the pathogenesis of Parkinson's disease.  

PubMed

Parkinson's disease is the second most common neurodegenerative movement disorder; however, its etiology remains elusive. Nevertheless, in vivo observations have concluded that oxidative stress is one of the most common causes in the pathogenesis of Parkinson's disease. It is known that mitochondria play a crucial role in reactive oxygen species-mediated pathways, and several gene products that associate with mitochondrial function are the subject of Parkinson's disease research. The PTEN-induced kinase 1 (PINK1) protects cells from mitochondrial dysfunction and is linked to the autosomal recessive familial form of the disease. PINK1 is a key player in many signaling pathways engaged in mitophagy, apoptosis, or microglial inflammatory response and is induced by oxidative stress. Several proteins participate in mitochondrial networks, and they are associated with PINK1. The E3 ubiquitin ligase Parkin, the protease presenilin-associated rhomboid-like serine protease, the tyrosine kinase c-Abl, the protein kinase MARK2, the protease HtrA2, and the tumor necrosis factor receptor-associated protein 1 (TRAP1) provide different steps of control in protection against oxidative stress. Furthermore, environmental toxins, such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, have been identified as contributors to parkinsonism by increasing oxidative stress in dopaminergic neurons. The present review discusses the mechanisms and effects of oxidative stress, the emerging concept of the impact of environmental toxins, and a possible neuroprotective role of the antioxidant astaxanthin in various neurodegenerative disorders with particular emphasis in Parkinson's disease. PMID:24522549

Gaki, Georgia S; Papavassiliou, Athanasios G

2014-06-01

360

The mifepristone-inducible gene regulatory system in mouse models of disease and gene therapy.  

PubMed

The mifepristone (Mfp)-inducible gene regulatory system is designed to allow control of the spatiotemporal expression of transgenes in vivo in a ligand-dependent manner. This regulatory system is composed of two components: (1) a chimeric transactivator protein that activates transgene transcription only in the presence of the progesterone antagonist Mfp, and (2) a target transgene placed in the context of a promoter which is responsive only to the Mfp-bound chimeric transactivator. Incorporation of the components of the Mfp-inducible gene regulatory system into transgenic mice has resulted in the establishment of several novel, Mfp-dependent models of disease. Similarly, adaptation of the Mfp-inducible system for use in gene knockout models has resulted in the development of new gene ablation technology which is both tissue-specific and Mfp-dependent. Additionally, the Mfp-inducible gene regulatory system has been used in animal experiments involving somatic gene therapy, where it has shown considerable promise in the regulation of both reporter and therapeutic gene expression. This review focuses on recent application of the Mfp-inducible system to transgenic models, gene knockout models, and somatic gene therapy experiments. In so doing, it demonstrates the considerable promise that future use of this system holds for better understanding and treatment of human disease. PMID:12240599

Ngan, Elly S W; Schillinger, Kurt; DeMayo, Francesco; Tsai, Sophia Y

2002-04-01

361

Increasing both CoCrMo-alloy Particle Size and Surface Irregularity Induces Increased Macrophage Inflammasome Activation In vitro Potentially through Lysosomal Destabilization Mechanisms  

PubMed Central

Recent investigations indicate that innate immune “danger-signaling” pathways mediate metal implant debris induced-inflammatory responses, e.g. NALP3 inflammasome. How the physical characteristics of particles, (size, shape and chemical composition) affect this inflammatory reactivity remains controversial. We examined the role of Cobalt-Chromium-Molybdenum (CoCrMo) alloy particle shape and size on human macrophage phagocytosis, lysosomal destabilization, and inflammasome activation. Round/smooth vs. irregularly shaped/rough CoCrMo-alloy particles of ~1µm and 6 to 7µm diameter were investigated for differential lysosomal damage and inflammasome activation in human monocytes/macrophages. While spherical/smooth 1µm CoCrMo-alloy particles did not measurably affect macrophage IL-1? production, irregular 1µm CoCrMo-alloy particles induced significant IL-1? increases over controls. Both round/smooth particles and irregular CoCrMo-alloy particles that were 6 to 7µ min size induced >10-fold increases in IL-1? production compared to similarly shaped smaller particles (p<0.05). Larger irregular particles induced a greater degree of intracellular lysosomal damage and a >3-fold increase in IL-1? vs. similarly sized round/smooth particles (at an equal dose, particles/cell). CoCrMo-alloy particle-size-induced IL-1? production was dependent on the lysosomal protease Cathepsin B, further supporting lysosomal destabilization as causative in inflammation. Phagocytosable larger/irregular shaped particles (6µm) demonstrated the greatest lysosomal destabilization (observed immunofluorescently) and inflammatory reactivity when compared on an equal dose basis (particles/cell) to smaller/spherical 1µm particles in vitro. PMID:23794526

Caicedo, Marco S; Samelko, Lauryn; McAllister, Kyron; Jacobs, Joshua J; Hallab, Nadim J

2014-01-01

362

Animal-induced injuries and disease, viral infections, neonatal jaundice, and immunizations.  

PubMed

This review highlights recent advances in four areas of interest to the pediatrician: animal-induced injuries and disease, viral infections, neonatal jaundice, and immunizations. Molecular biology techniques are dramatically impacting our understanding of the pathophysiology of disease states. The application of this "modern medicine" to the bedside is rapidly becoming commonplace. As clinicians we need to understand the opportunities this affords us as well as its potential limitations. The above four areas of concern will be explored with this in mind. PMID:7951675

Gerson, W T

1994-08-01

363

Animal-induced injuries and disease, neonatal jaundice, viral infections, and immunizations.  

PubMed

This section features recent information in four areas of interest to the practicing pediatrician: animal-induced injuries and disease, neonatal jaundice, viral infections, and immunizations. The focus is on areas of major current discussion: the clinical spectrum and etiology of cat-scratch disease, the debate on new neonatal bilirubin recommendations, viral etiology of previously recognized clinical diagnoses, new immunization recommendations, and new vaccines. In addition, isolated but thought-provoking papers in the four areas over the past year are briefly discussed. By paying careful attention to highlighted articles, the busy practitioner should be able to keep abreast of rapid new developments. PMID:8374681

McIntire, S C; Urbach, A H; Bloom, M D; Mendelsohn, M J; Zitelli, B J; Gartner, J C

1993-08-01

364

Bone Turnover Markers Correlate with Implant fixation in a Rat Model Using LPS Doped Particles to Induced Implant Loosening1  

PubMed Central

Revision surgery for particle-induced implant loosening in total joint replacement is expected to increase dramatically over the next few decades. This study was designed to investigate if local tissue and serum markers of bone remodeling reflect implant fixation following administration of lipopolysaccharide (LPS)-doped polyethylene (PE) particles in a rat model. 24 rats received bilateral implantation of intramedullary titanium rods in the distal femur, followed by weekly bilateral intra-articular injection of either LPS-doped PE particles (n = 12) or vehicle which contained no particles (n= 12) for 12 weeks. The group in which the particles were injected had increased serum C-terminal telopeptide of type I collagen, decreased serum osteocalcin, increased peri-implant eroded surface, decreased peri-implant bone volume, and decreased mechanical pull-out strength compared to the controls. Implant fixation strength was positively correlated with peri-implant bone volume and serum osteocalcin and inversely correlated with serum C-terminal telopeptide of type I collagen, while energy to yield was positively correlated with serum osteocalcin and inversely correlated with the number of tartrate resistant acid phosphatase positive cells at the interface and the amount of peri-implant eroded surface. There was no effect on trabecular bone volume at a remote site. Thus, the particle-induced impaired fixation in this rat model was directly associated with local and serum markers of elevated bone resorption and depressed bone formation, supporting the rationale of exploring both anti-catabolic and anabolic strategies to treat and prevent particle-related implant osteolysis and loosening and indicating that serum markers may prove useful in tracking implant fixation. PMID:22275163

Liu, Shuo; Virdi, Amarjit S.; Sena, Kotaro; Hughes, W. Frank; Sumner, Dale R.

2011-01-01

365

Agglomerates of ultrafine particles of elemental carbon and TiO2 induce generation of lipid mediators in alveolar macrophages.  

PubMed Central

Agglomerates of ultrafine particles (AUFPs) may cause adverse health effects because of their large surface area. To evaluate physiologic responses of immune cells, we studied whether agglomerates of 77-nm elemental carbon [(EC); specific surface area 750 m2/g] and 21 nm titanium dioxide (TiO(2) particles (specific surface area 50 m(2)/g) affect the release of lipid mediators by alveolar macrophages (AMs). After 60-min incubation with 1 microg/mL AUFP-EC (corresponding to 7.5 cm(2) particle surface area), canine AMs (1 x 10(6) cells/mL) released arachidonic acid (AA) and the cyclooxygenase (COX) products prostaglandin E(2) (PGE(2), thromboxane B(2), and 12-hydroxyheptadecatrienoic acid but not 5-lipoxygenase (5-LO) products. AUFP-TiO(2) with a 10-fold higher mass (10 microg/mL) than AUFP-EC, but a similar particle surface area (5 cm(2) also induced AMs to release AA and COX products. Agglomerates of 250 nm TiO(2) particles (specific surface area 6.5 m(2)/g) at 100 microg/mL mass concentration (particle surface area 6.5 cm(2) showed the same response. Interestingly, 75 cm(2)/mL surface area of AUFP-EC and 16 cm(2)/mL surface area of AUFP-TiO(2) additionally induced the release of the 5-LO products leukotriene B(4) and 5-hydroxyeicosatetraenoic acid. Respiratory burst activity of stimulated canine neutrophils was partially suppressed by supernatants of AMs treated with various mass concentrations of the three types of particles. Inhibition of neutrophil activity was abolished by supernatants of AMs treated with COX inhibitors prior to AUFP-incubation. This indicates that anti-inflammatory properties of PGE(2) dominate the overall response of lipid mediators released by AUFP-affected AMs. In conclusion, our data indicate that surface area rather than mass concentration determines the effect of AUFPs, and that activation of phospholipase A(subscript)2(/subscript) and COX pathway occurs at a lower particle surface area than that of 5-LO-pathway. We hypothesize a protective role of PGE(2) in downregulating potential inflammatory reactions induced by ultrafine particles. PMID:11544173

Beck-Speier, I; Dayal, N; Karg, E; Maier, K L; Roth, C; Ziesenis, A; Heyder, J

2001-01-01

366

Nrf2 Is a Protective Factor against Oxidative Stresses Induced by Diesel Exhaust Particle in Allergic Asthma  

PubMed Central

Epidemiological studies have shown that air pollutants, such as diesel exhaust particle (DEP), are implicated in the increased incidence of allergic airway disorders. In vitro studies of molecular mechanisms have focused on the role of reactive oxygen species generated directly and indirectly by the exposure to DEP. Antioxidants effectively reduce the allergic inflammatory effects induced by DEP both in vitro and in vivo. On the other hand, Nrf2 is a transcription factor essential for the inducible and/or constitutive expression of phase II and antioxidant enzymes. Disruption of Nrf2 enhances susceptibility to airway inflammatory responses and exacerbation of allergic inflammation induced by DEP in mice. Host responses to DEP are regulated by a balance between antioxidants and proinflammatory responses. Nrf2 may be an important protective factor against oxidative stresses induced by DEP in airway inflammation and allergic asthma and is expected to contribute to chemoprevention against DEP health effects in susceptible individuals. PMID:23738037

Kawada, Tomoyuki; Azuma, Arata

2013-01-01

367

A single amino acid in VP2 is critical for the attachment of infectious bursal disease subviral particles to immobilized metal ions and DF-1 cells.  

PubMed

VP2 protein is the primary host-protective immunogen of infectious bursal disease virus (IBDV). His249 and His253 are two surface histidine residues in IBDV subviral particles (SVP), which is formed by twenty VP2 trimers when the VP2 protein of a local isolate is expressed. Here, a systemic study was performed to investigate His249 or/and His253 on self-assembly, cell attachment and immunogenicity of SVP. Point-mutagenesis of either or both histidine residues to alanine did not affect self-assembly of the SVP, but the SVP lost its Ni-NTA binding affinity when the His253 was mutated. Indirect immunofluorescence assays and inhibitory experiments also showed that His253 is essential for SVP to attach onto the DF-1 cells and to inhibit IBDV infection of DF-1 cells. Finally, enzyme-linked immunosorbent assays and chicken protection assays demonstrated that SVP with a mutation of His253 to alanine induced comparable neutralizing antibody titers in chickens as the wild-type SVP did. It was concluded that VP2's His253, a site not significant for the overall immunogenicity induced by SVP, is crucial for the binding affinity of SVP to Ni-NTA and the attachment of an IBDV host cell line. This is the first paper to decipher the role of His253 played in receptor interaction and immunogenicity. PMID:24732578

Lai, Su-Yuan; Chang, Gary Ro-lin; Yang, Han-Jen; Lee, Cheng-Chung; Lee, Long-Huw; Vakharia, Vikram N; Wang, Min-Ying

2014-07-01

368

Student Preferences Regarding Teaching Methods in a Drug-Induced Diseases and Clinical Toxicology Course  

PubMed Central

Objectives. To determine which teaching method in a drug-induced diseases and clinical toxicology course was preferred by students and whether their preference correlated with their learning of drug-induced diseases. Design. Three teaching methods incorporating active-learning exercises were implemented. A survey instrument was developed to analyze students’ perceptions of the active-learning methods used and how they compared to the traditional teaching method (lecture). Examination performance was then correlated to students’ perceptions of various teaching methods. Assessment. The majority of the 107 students who responded to the survey found traditional lecture significantly more helpful than active-learning methods (p=0.01 for all comparisons). None of the 3 active-learning methods were preferred over the others. No significant correlations were found between students’ survey responses and examination performance. Conclusions. Students preferred traditional lecture to other instructional methods. Learning was not influenced by the teaching method or by preference for a teaching method. PMID:23966726

Gim, Suzanna

2013-01-01

369

Ameliorative Potential of Tamarindus indica on High Fat Diet Induced Nonalcoholic Fatty Liver Disease in Rats  

PubMed Central

Nonalcoholic fatty liver disease (NAFLD), the prevalence of which is rising globally with current upsurge in obesity, is one of the most frequent causes of chronic liver diseases. The present study evaluated the ameliorative effect of extract of Tamarindus indica seed coat (ETS) on high fat diet (HFD) induced NAFLD, after daily administration at 45, 90, and 180?mg/kg body weight dose levels for a period of 6 weeks, in albino Wistar rats. Treatment with ETS at all tested dose levels significantly attenuated the pathological alterations associated with HFD induced NAFLD viz. hepatomegaly, elevated hepatic lipid and lipid peroxides, serum alanine aminotransferase, and free fatty acid levels as well as micro-/macrohepatic steatosis. Moreover, extract treatment markedly reduced body weight and adiposity along with an improvement in insulin resistance index. The study findings, therefore suggested the therapeutic potential of ETS against NAFLD, acting in part through antiobesity, insulin sensitizing, and antioxidant mechanisms. PMID:24688399

Sasidharan, Suja Rani; Anandakumar, Senthilkumar; Venkatesan, Vijayabalaji; Ariyattu Madhavan, Chandrasekharan Nair; Agarwal, Amit

2014-01-01

370

Key Node Selection for Containing Infectious Disease Spread Using Particle Swarm Optimization  

E-print Network

optimization problem is done using particle swarm optimization. Numerical simulation shows the effectiveness, it is not feasible and take much longer time which might miss the correct prevention timing. During the SARS period with SARS infectives were forced to follow their Home Quarantine Orders. Schools were closed. Public

Wong, Limsoon

371

Disease-corrected haematopoietic progenitors from Fanconi anaemia induced pluripotent stem cells  

Microsoft Academic Search

The generation of induced pluripotent stem (iPS) cells has enabled the derivation of patient-specific pluripotent cells and provided valuable experimental platforms to model human disease. Patient-specific iPS cells are also thought to hold great therapeutic potential, although direct evidence for this is still lacking. Here we show that, on correction of the genetic defect, somatic cells from Fanconi anaemia patients

Ángel Raya; Ignasi Rodríguez-Pizà; Guillermo Guenechea; Rita Vassena; Susana Navarro; María José Barrero; Antonella Consiglio; Maria Castellà; Paula Río; Eduard Sleep; Federico González; Gustavo Tiscornia; Elena Garreta; Trond Aasen; Anna Veiga; Inder M. Verma; Jordi Surrallés; Juan Bueren; Juan Carlos Izpisúa Belmonte

2009-01-01

372

Identification of antigenic proteins associated with trichloroethylene-induced autoimmune disease by serological proteome analysis  

SciTech Connect

Although many studies indicated that trichloroethylene (TCE) could induce autoimmune diseases and some protein adducts were detected, the proteins were not identified and mechanisms remain unknown. To screen and identify autoantigens which might be involved in TCE-induced autoimmune diseases, three groups of sera were collected from healthy donors (I), patients suffering from TCE-induced exfoliative dermatitis (ED) (II), and the healed ones (III). Serological proteome analysis (SERPA) was performed with total proteins of TCE-treated L-02 liver cells as antigen sources and immunoglobins of the above sera as probes. Highly immunogenic spots (2-fold or above increase compared with group I) in group II and III were submitted to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and tandem mass spectrometry sequencing. Western blot analysis was followed using commercial antibodies and individual serum. Six proteins were identified. Among them, Enoyl Coenzyme A hydratase peroxisoma 1 and lactate dehydrogenase B only showed stronger immunogenicity for group II sera, while Purine nucleoside phosphorylase, ribosomal protein P0 and proteasome activator subunit1 isoform1 also showed stronger immunogenicity for group III sera. Noteworthy, NM23 reacted only with group II sera. Western blot analysis of NM23 expression indicated that all of the individual serum of group II showed immune activity, which confirmed the validity of SERPA result. These findings revealed that there exist autoantibodies in group II and III sera. Besides, autoantibodies of the two stages of disease course were different. These autoantigens might serve as biomarkers to elucidate mechanisms underlying TCE toxicity and are helpful for diagnosis, therapy and prognosis of TCE-induced autoimmune diseases.

Liu Jianjun; Xing Xiumei; Huang Haiyan; Jiang Yingzhi; He Haowei; Xu Xinyun; Yuan Jianhui; Zhou Li; Yang Linqing [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, No. 21, Rd 1st Tianbei, 518020 Shenzhen (China); Zhuang Zhixiong, E-mail: bio-research@hotmail.co [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, No. 21, Rd 1st Tianbei, 518020 Shenzhen (China)

2009-11-01

373

Search for neutrino-induced particle showers with IceCube-40  

NASA Astrophysics Data System (ADS)

We report on the search for neutrino-induced particle showers, so-called cascades, in the IceCube-40 detector. The data for this search were collected between April 2008 and May 2009 when the first 40 IceCube strings were deployed and operational. Three complementary searches were performed, each optimized for different energy regimes. The analysis with the lowest energy threshold (2 TeV) targeted atmospheric neutrinos. A total of 67 events were found, consistent with the expectation of 41 atmospheric muons and 30 atmospheric neutrino events. The two other analyses targeted a harder, astrophysical neutrino flux. The analysis with an intermediate threshold of 25 TeV leads to the observation of 14 cascadelike events, again consistent with the prediction of 3.0 atmospheric neutrino and 7.7 atmospheric muon events. We hence set an upper limit of E2?lim?7.46×10-8 GeV sr-1 s-1 cm-2 (90% C.L.) on the diffuse flux from astrophysical neutrinos of all neutrino flavors, applicable to the energy range 25 TeV to 5 PeV, assuming an E?-2 spectrum and a neutrino flavor ratio of 1?1?1 at the Earth. The third analysis utilized a larger and optimized sample of atmospheric muon background simulation, leading to a higher energy threshold of 100 TeV. Three events were found over a background prediction of 0.04 atmospheric muon events and 0.21 events from the flux of conventional and prompt atmospheric neutrinos. Including systematic errors this corresponds to a 2.7? excess with respect to the background-only hypothesis. Our observation of neutrino event candidates above 100 TeV complements IceCube's recently observed evidence for high-energy astrophysical neutrinos.

Aartsen, M. G.; Abbasi, R.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Altmann, D.; Arguelles, C.; Arlen, T. C.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; BenZvi, S.; Berghaus, P.; Berley, D.; Bernardini, E.; Bernhard, A.; Besson, D. Z.; Binder, G.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bose, D.; Böser, S.; Botner, O.; Brayeur, L.; Bretz, H.-P.; Brown, A. M.; Bruijn, R.; Casey, J.; Casier, M.; Chirkin, D.; Christov, A.; Christy, B.; Clark, K.; Classen, L.; Clevermann, F.; Coenders, S.; Cohen, S.; Cowen, D. F.; Cruz Silva, A. H.; Danninger, M.; Daughhetee, J.; Davis, J. C.; Day, M.; de André, J. P. A. M.; De Clercq, C.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; Dunkman, M.; Eagan, R.; Eberhardt, B.; Eichmann, B.; Eisch, J.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Flis, S.; Franckowiak, A.; Frantzen, K.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Golup, G.; Gonzalez, J. G.; Goodman, J. A.; Góra, D.; Grandmont, D. T.; Grant, D.; Gretskov, P.; Groh, J. C.; Groß, A.; Ha, C.; Haj Ismail, A.; Hallen, P.; Hallgren, A.; Halzen, F.; Hanson, K.; Hebecker, D.; Heereman, D.; Heinen, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Homeier, A.; Hoshina, K.; Huang, F.; Huelsnitz, W.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobi, E.; Jacobsen, J.; Jagielski, K.; Japaridze, G. S.; Jero, K.; Jlelati, O.; Kaminsky, B.; Kappes, A.; Karg, T.; Karle, A.; Kauer, M.; Kelley, J. L.; Kiryluk, J.; Kläs, J.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kopper, C.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Krasberg, M.; Kriesten, A.; Krings, K.; Kroll, G.; Kunnen, J.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Landsman, H.; Larson, M. J.; Lesiak-Bzdak, M.; Leuermann, M.; Leute, J.; Lünemann, J.; Macías, O.; Madsen, J.; Maggi, G.; Maruyama, R.; Mase, K.; Matis, H. S.; McNally, F.; Meagher, K.; Merck, M.; Meures, T.; Miarecki, S.; Middell, E.; Milke, N.; Miller, J.; Mohrmann, L.; Montaruli, T.; Morse, R.; Nahnhauer, R.; Naumann, U.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke, A.; Odrowski, S.; Olivas, A.; Omairat, A.; O'Murchadha, A.; Palczewski, T.; Paul, L.; Pepper, J. A.; Pérez de los Heros, C.; Pfendner, C.; Pieloth, D.; Pinat, E.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Quinnan, M.; Rädel, L.; Rameez, M.; Rawlins, K.; Redl, P.; Reimann, R.; Resconi, E.; Rhode, W.; Ribordy, M.; Richman, M.; Riedel, B.; Robertson, S.; Rodrigues, J. P.; Rott, C.; Ruhe, T.; Ruzybayev, B.; Ryckbosch, D.; Saba, S. M.; Sander, H.-G.; Santander, M.; Sarkar, S.; Schatto, K.; Scheriau, F.; Schmidt, T.; Schmitz, M.; Schoenen, S.; Schöneberg, S.; Schönwald, A.; Schukraft, A.; Schulte, L.; Schulz, O.; Seckel, D.; Sestayo, Y.; Seunarine, S.; Shanidze, R.; Sheremata, C.; Smith, M. W. E.; Soldin, D.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stanisha, N. A.; Stasik, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strahler, E. A.; Ström, R.; Strotjohann, N. L.; Sullivan, G. W.; Taavola, H.; Taboada, I.; Tamburro, A.; Tepe, A.; Ter-Antonyan, S.; Teši?, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Tselengidou, M.; Unger, E.; Usner, M.; Vallecorsa, S.; van Eijndhoven, N.; Van Overloop, A.; van Santen, J.; Vehring, M.; Voge, M.; Vraeghe, M.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Weaver, Ch.; Wellons, M.; Wendt, C.; Westerhoff, S.; Whelan, B.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Ziemann, J.; Zierke, S.; Zoll, M.; IceCube Collaboration

2014-05-01

374

Particle-induced artifacts in the MTT and LDH viability assays  

PubMed Central

In vitro testing is a common first step in assessing combustion generated and engineered nanoparticle related health hazards. Commercially available viability assays are frequently used to compare the toxicity of different particle types and to generate dose response data. Nanoparticles, well known for having large surface areas and chemically active surfaces, may interfere with viability assays, producing a false assessment of toxicity and making it difficult to compare toxicity data. The objective of this study is to measure the extent of particle interference in two common viability assays, the MTT reduction and the lactate dehydrogenase (LDH) release assays. Diesel particles, activated carbon, flame soot, oxidized flame soot, and titanium dioxide particles are assessed for interactions with the MTT and LDH assay under cell-free conditions. Diesel particles, at concentrations as low as 0.05 ?g/ml, reduce MTT. Other particle types reduce MTT only at a concentration of 50 ?g/ml and higher. The activated carbon, soot, and oxidized soot particles bind LDH to varying extents, reducing the concentration measured in the LDH assay. The interfering effects of the particles explain in part the different toxicities measured in human bronchial epithelial cells (16HBE14o). We conclude that valid particle toxicity assessments can only be assured after first performing controls to verify that the particles under investigation do not interfere with a specific assay at the expected concentrations. PMID:22799765

Holder, Amara L.; Goth-Goldstein, Regine; Lucas, Donald; Koshland, Catherine P.

2012-01-01

375

Complexation- and ligand-induced metal release from 316L particles: importance of particle size and crystallographic structure.  

PubMed

Iron, chromium, nickel, and manganese released from gas-atomized AISI 316L stainless steel powders (sized <45 and <4 ?m) were investigated in artificial lysosomal fluid (ALF, pH 4.5) and in solutions of its individual inorganic and organic components to determine its most aggressive component, elucidate synergistic effects, and assess release mechanisms, in dependence of surface changes using atomic absorption spectroscopy, Raman, XPS, and voltammetry. Complexation is the main reason for metal release from 316L particles immersed in ALF. Iron was mainly released, while manganese was preferentially released as a consequence of the reduction of manganese oxide on the surface. These processes resulted in highly complexing media in a partial oxidation of trivalent chromium to hexavalent chromium on the surface. The extent of metal release was partially controlled by surface properties (e.g., availability of elements on the surface and structure of the outermost surface) and partially by the complexation capacity of the different metals with the complexing agents of the different media. In general, compared to the coarse powder (<45 ?m), the fine (<4 ?m) powder displayed significantly higher released amounts of metals per surface area, increased with increased solution complexation capacity, while less amounts of metals were released into non-complexing solutions. Due to the ferritic structure of lower solubility for nickel of the fine powder, more nickel was released into all solutions compared with the coarser powder. PMID:21691833

Hedberg, Yolanda; Hedberg, Jonas; Liu, Yi; Wallinder, Inger Odnevall

2011-12-01

376

Depletion of Alveolar Macrophages Ameliorates Virus-Induced Disease following a Pulmonary Coronavirus Infection  

PubMed Central

Coronaviruses cause respiratory disease in humans that can range from mild to severe. However, the pathogenesis of pulmonary coronavirus infections is poorly understood. Mouse hepatitis virus type 1 (MHV-1) is a group 2 coronavirus capable of causing severe morbidity and mortality in highly susceptible C3H/HeJ mice. We have previously shown that both CD4 and CD8 T cells play a critical role in mediating MHV-1-induced disease. Here we evaluated the role of alveolar macrophages (AM) in modulating the adaptive immune response and subsequent disease. Depletion of AM using clodronate liposomes administered prior to MHV-1 infection was associated with a significant amelioration of MHV-1-induced morbidity and mortality. AM depletion resulted in a decreased number of virus-specific CD4 T cells in the lung airways. In addition, a significant increase in the frequency and total number of Tregs in the lung tissue and lung airways was observed following MHV-1 infection in mice depleted of AM. Our results indicate that AM play a critical role in modulating MHV-1-induced morbidity and mortality. PMID:24608125

Hartwig, Stacey M.; Holman, Kaitlyn M.; Varga, Steven M.

2014-01-01

377

Fluorescent light-induced chromatid breaks distinguish Alzheimer disease cells from normal cells in tissue culture.  

PubMed

The neurodegeneration and amyloid deposition of sporadic Alzheimer disease (AD) also occur in familial AD and in all trisomy-21 Down syndrome (DS) patients, suggesting a common pathogenetic mechanism. We investigated whether defective processing of damaged DNA might be that mechanism, as postulated for the neurodegeneration in xeroderma pigmentosum, a disease with defective repair not only of UV radiation-induced, but also of some oxygen free radical-induced, DNA lesions. We irradiated AD and DS skin fibroblasts or blood lymphocytes with fluorescent light, which is known to cause free radical-induced DNA damage. The cells were then treated with either beta-cytosine arabinoside (araC) or caffeine, and chromatid breaks were quantified. At least 28 of 31 normal donors and 10 of 11 donors with nonamyloid neurodegenerations gave normal test results. All 12 DS, 11 sporadic AD, and 16 familial AD patients tested had abnormal araC and caffeine tests, as did XP-A cells. In one of our four AD families, an abnormal caffeine test was found in all 10 afflicted individuals (including 3 asymptomatic when their skin biopsies were obtained) and in 8 of 11 offspring at a 50% risk for AD. Our tests could prove useful in predicting inheritance of familial AD and in supporting, or rendering unlikely, the diagnosis of sporadic AD in patients suspected of having the disease. PMID:8643543

Parshad, R P; Sanford, K K; Price, F M; Melnick, L K; Nee, L E; Schapiro, M B; Tarone, R E; Robbins, J H

1996-05-14

378

Analysis of Clonostachys rosea-Induced Resistance to Tomato Gray Mold Disease in Tomato Leaves  

PubMed Central

Tomato gray mold disease, caused by Botrytis cinerea, is a serious disease in tomato. Clonostachys rosea is an antagonistic microorganism to B. cinerea. To investigate the induced resistance mechanism of C. rosea, we examined the effects of these microorganisms on tomato leaves, along with changes in the activities of three defense enzymes (PAL, PPO, GST), second messengers (NO, H2O2, O2?) and phytohormones (IAA, ABA, GA3, ZT, MeJA, SA and C2H4). Compared to the control, all treatments induced higher levels of PAL, PPO and GST activity in tomato leaves and increased NO, SA and GA3 levels. The expression of WRKY and MAPK, two important transcription factors in plant disease resistance, was upregulated in C. rosea- and C. rosea plus B. cinerea-treated samples. Two-dimensional gel electrophoresis analysis showed that two abundant proteins were present in the C. rosea plus B. cinerea-treated samples but not in the other samples. These proteins were determined (by mass spectrum analysis) to be LEXYL2 (?-xylosidase) and ATP synthase CF1 alpha subunit. Therefore, C. rosea plus B. cinerea treatment induces gray mold resistance in tomato. This study provides a basis for elucidating the mechanism of C. rosea as a biocontrol agent. PMID:25061981

Guan, Xin; Chen, Xiuling; Chen, Hongyu; Zhang, Jian; Zhang, Junfeng; Li, Jingfu; Yang, Yijun; Wang, Aoxue

2014-01-01

379

Diet-Induced Dysbiosis of the Intestinal Microbiota and the Effects on Immunity and Disease  

PubMed Central

The gastrointestinal (GI) microbiota is the collection of microbes which reside in the GI tract and represents the largest source of non-self antigens in the human body. The GI tract functions as a major immunological organ as it must maintain tolerance to commensal and dietary antigens while remaining responsive to pathogenic stimuli. If this balance is disrupted, inappropriate inflammatory processes can result, leading to host cell damage and/or autoimmunity. Evidence suggests that the composition of the intestinal microbiota can influence susceptibility to chronic disease of the intestinal tract including ulcerative colitis, Crohn’s disease, celiac disease and irritable bowel syndrome, as well as more systemic diseases such as obesity, type 1 diabetes and type 2 diabetes. Interestingly, a considerable shift in diet has coincided with increased incidence of many of these inflammatory diseases. It was originally believed that the composition of the intestinal microbiota was relatively stable from early childhood; however, recent evidence suggests that diet can cause dysbiosis, an alteration in the composition of the microbiota, which could lead to aberrant immune responses. The role of the microbiota and the potential for diet-induced dysbiosis in inflammatory conditions of the GI tract and systemic diseases will be discussed. PMID:23016134

Brown, Kirsty; DeCoffe, Daniella; Molcan, Erin; Gibson, Deanna L.

2012-01-01

380

Low doses of alpha particles do not induce sister chromatid exchanges in bystander Chinese hamster cells defective in homologous recombination  

SciTech Connect

We reported previously that the homologous recombinational repair (HRR)-deficient Chinese hamster mutant cell line irs3 (deficient in the Rad51 paralog Rad51C) showed only a 50% spontaneous frequency of sister chromatid exchange (SCE) as compared to parental wild-type V79 cells. Furthermore, when irradiated with very low doses of alpha particles, SCEs were not induced in irs3 cells, as compared to a prominent bystander effect observed in V79 cells (Nagasawa et al., Radiat. Res. 164, 141-147, 2005). In the present study, we examined additional Chinese hamster cell lines deficient in the Rad51 paralogs Rad51C, Rad51D, Xrcc2, and Xrcc3 as well as another essential HRR protein, Brca2. Spontaneous SCE frequencies in non-irradiated wild-type cell lines CHO, AA8 and V79 were 0.33 SCE/chromosome, whereas two Rad51C-deficient cell lines showed only 0.16 SCE/chromosome. Spontaneous SCE frequencies in cell lines defective in Rad51D, Xrcc2, Xrcc3, and Brca2 ranged from 0.23-0.33 SCE/chromosome, 0-30% lower than wild-type cells. SCEs were induced significantly 20-50% above spontaneous levels in wild-type cells exposed to a mean dose of 1.3 mGy of alpha particles (<1% of nuclei traversed by an alpha particle). However, induction of SCEs above spontaneous levels was minimal or absent after {alpha}-particle irradiation in all of the HRR-deficient cell lines. These data suggest that Brca2 and the Rad51 paralogs contribute to DNA damage repair processes induced in bystander cells (presumably oxidative damage repair in S-phase cells) following irradiation with very low doses of alpha particles.

Nagasawa, H; Wilson, P F; Chen, D J; Thompson, L H; Bedford, J S; Little, J B

2007-10-26

381

DNA immunization with HBsAg-based particles expressing a B cell epitope of amyloid ?-peptide attenuates disease progression and prolongs survival in a mouse model of Alzheimer's disease.  

PubMed

Alzheimer's disease (AD) is an incurable and progressive neurodegenerative senile disorder associated with the brain accumulation of A? plaques. Although vaccines that reduce A? plaques can control AD, the rationale for their use at the onset of the disease remains debatable. Old humans and mice usually respond poorly to vaccines due to presumably age-related immunological impairments. Here, we report that by modifying vaccines, the poor responsiveness of old mice can be reversed. Unlike the A? peptide vaccine, DNA immunizations with the amino-terminal A?(1-11) fragment exposed on the surface of HBsAg particles elicit high levels of anti-A? antibody both in young and old mice. Importantly, in AD model 3xTgAD mice, the vaccine reduced A? plaques, ameliorated cognitive impairments and, surprisingly, significantly increased life span. Hence, we propose that vaccines targeting A?(1-11) can efficiently combat AD-induced pathological alterations and provide survival benefit in patients with AD. PMID:22248819

Olkhanud, Purevdorj B; Mughal, Mohammed; Ayukawa, Koichi; Malchinkhuu, Enkhzol; Bodogai, Monica; Feldman, Neil; Rothman, Sarah; Lee, Jong-Hwan; Chigurupati, Srinivasulu; Okun, Eitan; Nagashima, Kunio; Mattson, Mark P; Biragyn, Arya

2012-02-21

382

Mannan induces ROS-regulated, IL-17A-dependent psoriasis arthritis-like disease in mice.  

PubMed

Psoriasis (Ps) and psoriasis arthritis (PsA) are poorly understood common diseases, induced by unknown environmental factors, affecting skin and articular joints. A single i.p. exposure to mannan from Saccharomyces cerevisiae induced an acute inflammation in inbred mouse strains resembling human Ps and PsA-like disease, whereas multiple injections induced a relapsing disease. Exacerbation of disease severity was observed in mice deficient for generation of reactive oxygen species (ROS). Interestingly, restoration of ROS production, specifically in macrophages, ameliorated both skin and joint disease. Neutralization of IL-17A, mainly produced by ?? T cells, completely blocked disease symptoms. Furthermore, mice depleted of granulocytes were resistant to disease development. In contrast, certain acute inflammatory mediators (C5, Fc? receptor III, mast cells, and histamine) and adaptive immune players (?? T and B cells) were redundant in disease induction. Hence, we propose that mannan-induced activation of macrophages leads to TNF-? secretion and stimulation of local ?? T cells secreting IL-17A. The combined action of activated macrophages and IL-17A produced in situ drives neutrophil infiltration in the epidermis and dermis of the skin, leading to disease manifestations. Thus, our finding suggests a new mechanism triggered by exposure to exogenous microbial components, such as mannan, that can induce and exacerbate Ps and PsA. PMID:25136095

Khmaladze, Ia; Kelkka, Tiina; Guerard, Simon; Wing, Kajsa; Pizzolla, Angela; Saxena, Amit; Lundqvist, Katarina; Holmdahl, Meirav; Nandakumar, Kutty Selva; Holmdahl, Rikard

2014-09-01

383

Size-partitioning of an urban aerosol to identify particle determinants involved in the proinflammatory response induced in airway epithelial cells  

PubMed Central

Background The contribution of air particles in human cardio-respiratory diseases has been enlightened by several epidemiological studies. However the respective involvement of coarse, fine and ultrafine particles in health effects is still unclear. The aim of the present study is to determine which size fraction from a chemically characterized background aerosol has the most important short term biological effect and to decipher the determinants of such a behaviour. Results Ambient aerosols were collected at an urban background site in Paris using four 13-stage low pressure cascade impactors running in parallel (winter and summer 2005) in order to separate four size-classes (PM0.03–0.17 (defined here as ultrafine particles), PM0.17–1 (fine), PM1–2.5(intermediate) and PM2.5–10 (coarse)). Accordingly, their chemical composition and their pro-inflammatory potential on human airway epithelial cells were investigated. Considering isomass exposures (same particle concentrations for each size fractions) the pro-inflammatory response characterized by Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF) release was found to decrease with aerosol size with no seasonal dependency. When cells were exposed to isovolume of particle suspensions in order to respect the particle proportions observed in ambient air, the GM-CSF release was maximal with the fine fraction. In presence of a recombinant endotoxin neutralizing protein, the GM-CSF release induced by particles is reduced for all size-fractions, with exception of the ultra-fine fraction which response is not modified. The different aerosol size-fractions were found to display important chemical differences related to the various contributing primary and secondary sources and aerosol age. The GM-CSF release was correlated to the organic component of the aerosols and especially its water soluble fraction. Finally, Cytochrome P450 1A1 activity that reflects PAH bioavailability varied as a function of the season: it was maximal for the fine fraction in winter and for the ultrafine fraction in summer. Conclusion In the frame of future regulations, a particular attention should thus be paid to the ultrafine/fine (here referred to as PM1) fraction due to their overwhelming anthropogenic origin and predominance in the urban aerosol and their pro-inflammatory potential. PMID:19302717

Ramgolam, Kiran; Favez, Olivier; Cachier, Helene; Gaudichet, Annie; Marano, Francelyne; Martinon, Laurent; Baeza-Squiban, Armelle

2009-01-01

384

Light-induced quenching of chlorophyll fluorescence at 77 K in leaves, chloroplasts and Photosystem II particles  

Microsoft Academic Search

The light-induced chlorophyll (Chl) fluorescence decline at 77 K was investigated in segments of leaves, isolated thylakoids\\u000a or Photosystem (PS) II particles. The intensity of chlorophyll fluorescence declines by about 40% upon 16 min of irradiation\\u000a with 1000 ?mol m?2?s?1 of white light. The decline follows biphasic kinetics, which can be fitted by two exponentials with amplitudes of approximately\\u000a 20

Pavel Šiffel; Ivana Hunalová; Karel Rohá?ek

2000-01-01

385

The effect of neonatal thymectomy on Tamiami virus-induced central nervous system disease.  

PubMed

Tamiami virus, a member of the arenavirus group, produces an acute CNS disease in suckling mice manifested primarily by cerebellar ataxia, paralysis, convulsions, and death. Animals that survive are left with an asymptomatic cerebellar heterotopia. Neonatal thymectomy prevents both acute CNS disease and the resultant cerebellar heterotopia despite equivalent titers of virus and concentrations of viral antigen in the brains of both thymectomized and nonthymectomized infected mice. Inflammatory CNS disease and cerebellar germinal cell necrosis do not develop in thymectomized mice examined more than three months after infection. Viremia and complement-fixing antibody occur in both groups of mice with slightly higher antibody titers in nonthymectomized mice. Tamiami virus-induced cerebellar heterotopia appears to be immunologically-mediated, but the immunopathologic cerebellar lesion differs from the frank necrosis of the brain produced by both Tacaribe and LCM virus in newborn mice. PMID:1123649

Friedman, H M; Gilden, D H; Roosa, R A; Nathanson, N

1975-03-01

386

The molecular basis for disease phenotype in chronic Chlamydia-induced arthritis  

PubMed Central

Genital Chlamydia trachomatis infections can elicit an inflammatory arthritis in some individuals, and recent surprising studies have demonstrated that only ocular (trachoma) strains, not genital strains, of the organism are present in the synovial tissues of patients with the disease. This observation suggests an explanation for the small proportion of genitally-infected patients who develop Chlamydia-induced arthritis. Other recent studies have begun to identify the specific chlamydial gene products that elicit the synovial inflammatory response during both active and quiescent disease, although much more study will be required to complete the understanding of that complex process of host–pathogen interaction. Several newly developed experimental methods and approaches for study of the process will enable identification of new therapeutic targets, and possibly strategies for prevention of the disease altogether. PMID:23440251

Carter, John D; Gerard, Herve C; Whittum-Hudson, Judith A; Hudson, Alan P

2013-01-01

387

Induced pluripotent stem cells from patients with Huntington's disease show CAG-repeat-expansion-associated phenotypes.  

PubMed

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded stretch of CAG trinucleotide repeats that results in neuronal dysfunction and death. Here, The HD Consortium reports the generation and characterization of 14 induced pluripotent stem cell (iPSC) lines from HD patients and controls. Microarray profiling revealed CAG-repeat-expansion-associated gene expression patterns that distinguish patient lines from controls, and early onset versus late onset HD. Differentiated HD neural cells showed disease-associated changes in electrophysiology, metabolism, cell adhesion, and ultimately cell death for lines with both medium and longer CAG repeat expansions. The longer repeat lines were however the most vulnerable to cellular stressors and BDNF withdrawal, as assessed using a range of assays across consortium laboratories. The HD iPSC collection represents a unique and well-characterized resource to elucidate disease mechanisms in HD and provides a human stem cell platform for screening new candidate therapeutics. PMID:22748968

2012-08-01

388

Induced Pluripotent Stem Cells from Patients with Huntington's Disease Show CAG Repeat Expansion Associated Phenotypes  

PubMed Central

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded stretch of CAG trinucleotide repeats that results in neuronal dysfunction and death. Here, the HD consortium reports the generation and characterization of 14 induced pluripotent stem cell (iPSC) lines from HD patients and controls. Microarray profiling revealed CAG expansion-associated gene expression patterns that distinguish patient lines from controls, and early onset versus late onset HD. Differentiated HD neural cells showed disease associated changes in electrophysiology, metabolism, cell adhesion, and ultimately cell death for lines with both medium and longer CAG repeat expansions. The longer repeat lines were however the most vulnerable to cellular stressors and BDNF withdrawal using a range of assays across consortium laboratories. The HD iPSC collection represents a unique and well-characterized resource to elucidate disease mechanisms in HD and provides a novel human stem cell platform for screening new candidate therapeutics. PMID:22748968

Mattis, Virginia B; Svendsen, Soshana P; Ebert, Allison; Svendsen, Clive N; King, Alvin R; Casale, Malcolm; Winokur, Sara T; Batugedara, Gayani; Vawter, Marquis; Donovan, Peter J; Lock, Leslie F; Thompson, Leslie M; Zhu, Yu; Fossale, Elisa; Singh Atwal, Ranjit; Gillis, Tammy; Mysore, Jayalakshmi; Li, Jian-hong; Seong, IhnSik; Shen, Yiping; Chen, Xiaoli; Wheeler, Vanessa C; MacDonald, Marcy E; Gusella, James F; Akimov, Sergey; Arbez, Nicolas; Juopperi, Tarja; Ratovitski, Tamara; Chiang, Jason H; Kim, Woon Roung; Chighladze, Eka; Watkin, Erin; Zhong, Chun; Makri, Georgia; Cole, Robert N; Margolis, Russell L; Song, Hongjun; Ming, Guoli; Ross, Christopher A; Kaye, Julia A; Daub, Aaron; Sharma, Punita; Mason, Amanda R; Finkbeiner, Steven; Yu, Junying; Thomson, James A; Rushton, David; Brazier, Stephen P; Battersby, Alysia A; Redfern, Amanda; Tseng, Hsui-Er; Harrison, Alexander W; Kemp, Paul J; Allen, Nicholas D; Onorati, Marco; Castiglioni, Valentina; Cattaneo, Elena; Arjomand, Jamshid

2013-01-01

389

Pathobiology and subgroup specificity of disease induced by Rous associated virus 7 (RAV-7)  

SciTech Connect

When Rous associated virus 7 (RAV-7) was injected intravenously into 10-day old chicken embryos, a disease syndrome developed which was characterized by stunting, hyperlipidemia, hypothyroidism, and hyperinsulinemia. Stocks of RAV-7, a subgroup C avian leukosis virus, were obtained by end-point purification on chick embryo fibroblast cells. The size of the viral RNA was 8.2 kb and the protein banding pattern on polyacrylamide gels was typical of avian leukosis viruses. These results indicated that RAV-7 was a non-defective avian leukosis virus and no sarcoma or defective leukemia viruses were present in the RAV-7 stock. RAV-7 induced a unique disease syndrome although infection by three other subgroup C avian leukosis viruses (tdB77, tdPrC, and RAV-49) resulted in an identical lymphoblastoid infiltration of the thyroid and pancreas. An examination of disease induced by avian leukosis viruses from subgroups A, B, D, and F showed that infection by any of these subgroups did not result in the typical RAV-7 disease syndrome.

Carter, J.Y.

1983-01-01

390

Oligomeric amyloid ? induces IL-1? processing via production of ROS: implication in Alzheimer's disease  

PubMed Central

Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by progressive neuronal loss and cognitive decline. Oligomeric amyloid ? (oA?) is involved in the pathogenesis of AD by affecting synaptic plasticity and inhibiting long-term potentiation. Although several lines of evidence suggests that microglia, the resident immune cells in the central nervous system (CNS), are neurotoxic in the development of AD, the mechanism whether or how oA? induces microglial neurotoxicity remains unknown. Here, we show that oA? promotes the processing of pro-interleukin (IL)-1? into mature IL-1? in microglia, which then enhances microglial neurotoxicity. The processing is induced by an increase in activity of caspase-1 and NOD-like receptor family, pyrin domain containing 3 (NLRP3) via mitochondrial reactive oxygen species (ROS) and partially via NADPH oxidase-induced ROS. The caspase-1 inhibitor Z-YVAD-FMK inhibits the processing of IL-1?, and attenuates microglial neurotoxicity. Our results indicate that microglia can be activated by oA? to induce neuroinflammation through processing of IL-1?, a pro-inflammatory cytokine, in AD. PMID:24357806

Parajuli, B; Sonobe, Y; Horiuchi, H; Takeuchi, H; Mizuno, T; Suzumura, A

2013-01-01

391

Closed-form expressions for particle relative velocities induced by turbulence  

E-print Network

In this note we present complete, closed-form expressions for random relative velocities between colliding particles of arbitrary size in nebula turbulence. These results are exact for very small particles (those with stopping times much shorter than the large eddy overturn time) and are also surprisingly accurate in complete generality (that is, also apply for particles with stopping times comparable to, or much longer than, the large eddy overturn time). We note that some previous studies may have adopted previous simple expressions, which we find to be in error regarding the size dependence in the large particle regime.

C. W. Ormel; J. N. Cuzzi

2007-02-12

392

Amyloid ?-Peptide (1-42)-Induced Oxidative Stress in Alzheimer Disease: Importance in Disease Pathogenesis and Progression  

PubMed Central

Abstract Significance: Alzheimer disease (AD) is an age-related neurodegenerative disease. AD is characterized by progressive cognitive impairment. One of the main histopathological hallmarks of AD brain is the presence of senile plaques (SPs) and another is elevated oxidative stress. The main component of SPs is amyloid beta-peptide (A?) that is derived from the proteolytic cleavage of amyloid precursor protein. Recent Advances: Recent studies are consistent with the notion that methionine present at 35 position of A? is critical to A?-induced oxidative stress and neurotoxicity. Further, we also discuss the signatures of oxidatively modified brain proteins, identified using redox proteomics approaches, during the progression of AD. Critical Issues: The exact relationships of the specifically oxidatively modified proteins in AD pathogenesis require additional investigation. Future Directions: Further studies are needed to address whether the therapies directed toward brain oxidative stress and oxidatively modified key brain proteins might help delay or prevent the progression of AD. Antioxid. Redox Signal. 19, 823–835. PMID:23249141

Swomley, Aaron M.; Sultana, Rukhsana

2013-01-01

393

COX-2 expression induced by diesel particles involves chromatin modification and degradation of HDAC1  

EPA Science Inventory

Cyclooxygenase-2 (COX-2) plays an important role in the inflammatory response induced by physiologic and stress stimuli. Exposure to diesel exhaust particulate matter (DEP) has been shown to induce pulmonary inflammation and exacerbate asthma and chronic obstructive pulmonary dis...

394

Unconventional maturation of dendritic cells induced by particles from the laminated layer of larval Echinococcus granulosus.  

PubMed

The larval stage of the cestode parasite Echinococcus granulosus causes hydatid disease in humans and livestock. This infection is characterized by the growth in internal organ parenchymae of fluid-filled structures (hydatids) that elicit surprisingly little inflammation in spite of their massive size and persistence. Hydatids are protected by a millimeter-thick layer of mucin-based extracellular matrix, termed the laminated layer (LL), which is thought to be a major factor determining the host response to the infection. Host cells can interact both with the LL surface and with materials that are shed from it to allow parasite growth. In this work, we analyzed the response of dendritic cells (DCs) to microscopic pieces of the native mucin-based gel of the LL (pLL). In vitro, this material induced an unusual activation state characterized by upregulation of CD86 without concomitant upregulation of CD40 or secretion of cytokines (interleukin 12 [IL-12], IL-10, tumor necrosis factor alpha [TNF-?], and IL-6). When added to Toll-like receptor (TLR) agonists, pLL-potentiated CD86 upregulation and IL-10 secretion while inhibiting CD40 upregulation and IL-12 secretion. In vivo, pLL also caused upregulation of CD86 and inhibited CD40 upregulation in DCs. Contrary to expectations, oxidation of the mucin glycans in pLL with periodate did not abrogate the effects on cells. Reduction of disulfide bonds, which are known to be important for LL structure, strongly diminished the impact of pLL on DCs without altering the particulate nature of the material. In summary, DCs respond to the LL mucin meshwork with a "semimature" activation phenotype, both in vitro and in vivo. PMID:24842926

Casaravilla, Cecilia; Pittini, Alvaro; Rückerl, Dominik; Seoane, Paula I; Jenkins, Stephen J; MacDonald, Andrew S; Ferreira, Ana M; Allen, Judith E; Díaz, Alvaro

2014-08-01

395

NASA aerial applications wake interaction research. [particle trajectories in aircraft induced wakes  

NASA Technical Reports Server (NTRS)

A computer code has been developed for predicting trajectories of particles released in the wakes of airplanes or helicopters. The code accounts for effects of turbulence, crosswind, propeller slipstream, terrain variations, and plant canopy density on particle trajectories. Comparisons are given between experiments and theory. Applications of the code for spray pattern improvement are illustrated.

Morris, D. J.; Croom, C. C.; Holmes, B. J.; Van Dam, C. P.

1982-01-01

396

OXIDATIVE STRESS AND LIPID MEDIATORS INDUCED IN ALVEOLAR MACHROPHAGES BY ULTRAFINE PARTICLES  

EPA Science Inventory

In ambient aerosols, ultrafine particles (UFP) and their agglomerates are considered to be major factors contributing to adverse health effects. Reactivity of agglomerated UFP of elemental carbon (EC), Printex 90, Printex G, and diesel exhaust particles (DEP) was evaluated by the...

397

Assessment of soot particle vaporization effects during laser-induced incandescence with  

E-print Network

-scattering theory was used to invert the scattering data, revealing 80%­90% reductions in the soot particle volume generally focused on larger- sized particulate matter such as PM10 (particles less than 10 m in diameter of increased health concerns caused by finer particulate matter.1 Soot is generally accepted to contain

Hahn, David W.

398

Comparative Elongated Mineral Particle Toxicology & Erionite?s Apparent  High Potency for Inducing Mesothelioma  

EPA Science Inventory

Recent NHEERL research under EPA's Libby Action Plan has determined that elongated particle relative potency for rat pleural mesothelioma is best predicted on the basis of total external surface area (TSA) of slightly acid leached test samples which simulate particle bio-durabili...