Science.gov

Sample records for accelerating leukocyte tracking

  1. Tracking flow of leukocytes in blood for drug analysis

    NASA Astrophysics Data System (ADS)

    Basharat, Arslan; Turner, Wesley; Stephens, Gillian; Badillo, Benjamin; Lumpkin, Rick; Andre, Patrick; Perera, Amitha

    2011-03-01

    Modern microscopy techniques allow imaging of circulating blood components under vascular flow conditions. The resulting video sequences provide unique insights into the behavior of blood cells within the vasculature and can be used as a method to monitor and quantitate the recruitment of inflammatory cells at sites of vascular injury/ inflammation and potentially serve as a pharmacodynamic biomarker, helping screen new therapies and individualize dose and combinations of drugs. However, manual analysis of these video sequences is intractable, requiring hours per 400 second video clip. In this paper, we present an automated technique to analyze the behavior and recruitment of human leukocytes in whole blood under physiological conditions of shear through a simple multi-channel fluorescence microscope in real-time. This technique detects and tracks the recruitment of leukocytes to a bioactive surface coated on a flow chamber. Rolling cells (cells which partially bind to the bioactive matrix) are detected counted, and have their velocity measured and graphed. The challenges here include: high cell density, appearance similarity, and low (1Hz) frame rate. Our approach performs frame differencing based motion segmentation, track initialization and online tracking of individual leukocytes.

  2. TRACKING ACCELERATOR SETTINGS.

    SciTech Connect

    D OTTAVIO,T.; FU, W.; OTTAVIO, D.P.

    2007-10-15

    Recording setting changes within an accelerator facility provides information that can be used to answer questions about when, why, and how changes were made to some accelerator system. This can be very useful during normal operations, but can also aid with security concerns and in detecting unusual software behavior. The Set History System (SHS) is a new client-server system developed at the Collider-Accelerator Department of Brookhaven National Laboratory to provide these capabilities. The SHS has been operational for over two years and currently stores about IOOK settings per day into a commercial database management system. The SHS system consists of a server written in Java, client tools written in both Java and C++, and a web interface for querying the database of setting changes. The design of the SHS focuses on performance, portability, and a minimal impact on database resources. In this paper, we present an overview of the system design along with benchmark results showing the performance and reliability of the SHS over the last year.

  3. Event Tracking Model of Adhesion Identifies Load-bearing Bonds in Rolling Leukocytes

    PubMed Central

    POSPIESZALSKA, MARIA K.; ZARBOCK, ALEXANDER; PICKARD, JOHN E.; LEY, KLAUS

    2009-01-01

    Objectives P-selectin binding to P-selectin glycoprotein ligand (PSGL)-1 mediates leukocyte rolling under conditions of inflammation and injury. The objectives were to develop an efficient, high temporal resolution model for direct simulation of leukocyte rolling, and then to conduct a study of load-bearing bonds using the model. Methods A stochastic π-calculus-driven Event Tracking Model of Adhesion was developed and compared with experimental data. Multiple simulations for each case were conducted to obtain high confidence numerical characteristics of leukocyte rolling. Results Leukocyte rolling and the underlying P-selectin—PSGL-1 bonds were studied under low wall shear rate (25-50 s-1) conditions from measured parameters of leukocyte rolling and bond properties. For the first time, the location, number, lifetime, history, and kinetics of load-bearing bonds and their influence on cell rolling are identified. Instantaneous cell displacements, translational and rotational velocities, and cell-endothelium distances are derived. The model explains the commonly observed “stop-start” type rolling behavior and reveals that a few load-bearing bonds are sufficient to support rolling while a large number of bonds dissociate before becoming load-bearing. Conclusions The presented model provides a method for precise and direct simulation of leukocyte rolling, and sets a foundation upon which further refinements can be introduced. PMID:19023690

  4. Data acceptance for automated leukocyte tracking through segmentation of spatiotemporal images.

    PubMed

    Ray, Nilanjan; Acton, Scott T

    2005-10-01

    A crucial task in inflammation research and inflammatory drug validation is leukocyte velocity data collection from microscopic video imagery. Since manual methods are bias-prone and extremely time consuming, automated tracking methods are required to compute cell velocities. However, an automated tracking method is of little practical use unless it is accompanied by a mechanism to validate the tracker output. In this paper, we propose a validation technique that accepts or rejects the output of automated tracking methods. The proposed method first generates a spatiotemporal image from the cell locations given by a tracking method; then, it segments the spatiotemporal image to detect the presence or absence of a leukocyte. For segmenting the spatiotemporal images, we employ an edge-direction sensitive nonlinear filter followed by an active contour based technique. The proposed nonlinear filter, the maximum absolute average directional derivative (MAADD), first computes the magnitude of the mean directional derivative over an oriented line segment and then chooses the maximum of all such values within a range of orientations of the line segment. The proposed active contour segmentation is obtained via growing contours controlled by a two-dimensional force field, which is constructed by imposing a Dirichlet boundary condition on the gradient vector flow (GVF) field equations. The performance of the proposed validation method is reported here for the outputs of three different tracking techniques: the method was successful in 97% of the trials using manual tracking, in 94% using correlation tracking and in 93% using active contour tracking. PMID:16235656

  5. Accelerated Leadership Development: Fast Tracking School Leaders

    ERIC Educational Resources Information Center

    Earley, Peter; Jones, Jeff

    2010-01-01

    "Accelerated Leadership Development" captures and communicates the lessons learned from successful fast-track leadership programmes in the private and public sector, and provides a model which schools can follow and customize as they plan their own leadership development strategies. As large numbers of headteachers and other senior staff retire,…

  6. Adaptive and accelerated tracking-learning-detection

    NASA Astrophysics Data System (ADS)

    Guo, Pengyu; Li, Xin; Ding, Shaowen; Tian, Zunhua; Zhang, Xiaohu

    2013-08-01

    An improved online long-term visual tracking algorithm, named adaptive and accelerated TLD (AA-TLD) based on Tracking-Learning-Detection (TLD) which is a novel tracking framework has been introduced in this paper. The improvement focuses on two aspects, one is adaption, which makes the algorithm not dependent on the pre-defined scanning grids by online generating scale space, and the other is efficiency, which uses not only algorithm-level acceleration like scale prediction that employs auto-regression and moving average (ARMA) model to learn the object motion to lessen the detector's searching range and the fixed number of positive and negative samples that ensures a constant retrieving time, but also CPU and GPU parallel technology to achieve hardware acceleration. In addition, in order to obtain a better effect, some TLD's details are redesigned, which uses a weight including both normalized correlation coefficient and scale size to integrate results, and adjusts distance metric thresholds online. A contrastive experiment on success rate, center location error and execution time, is carried out to show a performance and efficiency upgrade over state-of-the-art TLD with partial TLD datasets and Shenzhou IX return capsule image sequences. The algorithm can be used in the field of video surveillance to meet the need of real-time video tracking.

  7. Tracking of Acceleration with HNJ Method

    SciTech Connect

    Ruggiero,A.

    2008-02-01

    After reviewing the principle of operation of acceleration with the method of Harmonic Number Jump (HNJ) in a Fixed-Field Alternating Gradient (FFAG) accelerator for protons and heavy ions, we report in this talk the results of computer simulations performed to assess the capability and the limits of the method in a variety of practical situations. Though the study is not yet completed, and there still remain other cases to be investigated, nonetheless the tracking results so far obtained are very encouraging, and confirm the validity of the method.

  8. Leukocyte mimetic polysaccharide microparticles tracked in vivo on activated endothelium and in abdominal aortic aneurysm.

    PubMed

    Bonnard, Thomas; Serfaty, Jean-Michel; Journé, Clément; Ho Tin Noe, Benoît; Arnaud, Denis; Louedec, Liliane; Derkaoui, Sidi Mohammed; Letourneur, Didier; Chauvierre, Cédric; Le Visage, Catherine

    2014-08-01

    We have developed injectable microparticles functionalized with fucoidan, in which sulfated groups mimic the anchor sites of P-selectin glycoprotein ligand-1 (PSGL-1), one of the principal receptors supporting leukocyte adhesion. These targeted microparticles were combined with a fluorescent dye and a T2(∗) magnetic resonance imaging (MRI) contrast agent, and then tracked in vivo with small animal imaging methods. Microparticles of 2.5μm were obtained by a water-in-oil emulsification combined with a cross-linking process of polysaccharide dextran, fluorescein isothiocyanate dextran, pullulan and fucoidan mixed with ultrasmall superparamagnetic particles of iron oxide. Fluorescent intravital microscopy observation revealed dynamic adsorption and a leukocyte-like behaviour of fucoidan-functionalized microparticles on a calcium ionophore induced an activated endothelial layer of a mouse mesentery vessel. We observed 20times more adherent microparticles on the activated endothelium area after the injection of functionalized microparticles compared to non-functionalized microparticles (197±11 vs. 10±2). This imaging tool was then applied to rats presenting an elastase perfusion model of abdominal aortic aneurysm (AAA) and 7.4T in vivo MRI was performed. Visual analysis of T2(∗)-weighted MR images showed a significant contrast enhancement on the inner wall of the aneurysm from 30min to 2h after the injection. Histological analysis of AAA cryosections revealed microparticles localized inside the aneurysm wall, in the same areas in which immunostaining shows P-selectin expression. The developed leukocyte mimetic imaging tool could therefore be relevant for molecular imaging of vascular diseases and for monitoring biologically active areas prone to rupture in AAA. PMID:24769117

  9. Hardware accelerator design for tracking in smart camera

    NASA Astrophysics Data System (ADS)

    Singh, Sanjay; Dunga, Srinivasa Murali; Saini, Ravi; Mandal, A. S.; Shekhar, Chandra; Vohra, Anil

    2011-10-01

    Smart Cameras are important components in video analysis. For video analysis, smart cameras needs to detect interesting moving objects, track such objects from frame to frame, and perform analysis of object track in real time. Therefore, the use of real-time tracking is prominent in smart cameras. The software implementation of tracking algorithm on a general purpose processor (like PowerPC) could achieve low frame rate far from real-time requirements. This paper presents the SIMD approach based hardware accelerator designed for real-time tracking of objects in a scene. The system is designed and simulated using VHDL and implemented on Xilinx XUP Virtex-IIPro FPGA. Resulted frame rate is 30 frames per second for 250x200 resolution video in gray scale.

  10. SimTrack: A compact c++ code for particle orbit and spin tracking in accelerators

    SciTech Connect

    Luo, Yun

    2015-08-29

    SimTrack is a compact c++ code of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam–beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam–beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam–beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

  11. SimTrack: A compact c++ library for particle orbit and spin tracking in accelerators

    SciTech Connect

    Luo, Yun

    2015-06-24

    SimTrack is a compact c++ library of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam-beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam-beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam-beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture, physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.

  12. SimTrack: A compact c++ code for particle orbit and spin tracking in accelerators

    DOE PAGESBeta

    Luo, Yun

    2015-08-29

    SimTrack is a compact c++ code of 6-d symplectic element-by-element particle tracking in accelerators originally designed for head-on beam–beam compensation simulation studies in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. It provides a 6-d symplectic orbit tracking with the 4th order symplectic integration for magnet elements and the 6-d symplectic synchro-beam map for beam–beam interaction. Since its inception in 2009, SimTrack has been intensively used for dynamic aperture calculations with beam–beam interaction for RHIC. Recently, proton spin tracking and electron energy loss due to synchrotron radiation were added. In this article, I will present the code architecture,more » physics models, and some selected examples of its applications to RHIC and a future electron-ion collider design eRHIC.« less

  13. Endogenous Thrombospondin-1 Regulates Leukocyte Recruitment and Activation and Accelerates Death from Systemic Candidiasis

    PubMed Central

    Martin-Manso, Gema; Navarathna, Dhammika H. M. L. P.; Galli, Susana; Soto-Pantoja, David R.; Kuznetsova, Svetlana A.; Tsokos, Maria; Roberts, David D.

    2012-01-01

    Disseminated Candida albicans infection results in high morbidity and mortality despite treatment with existing antifungal drugs. Recent studies suggest that modulating the host immune response can improve survival, but specific host targets for accomplishing this goal remain to be identified. The extracellular matrix protein thrombospondin-1 is released at sites of tissue injury and modulates several immune functions, but its role in C. albicans pathogenesis has not been investigated. Here, we show that mice lacking thrombospondin-1 have an advantage in surviving disseminated candidiasis and more efficiently clear the initial colonization from kidneys despite exhibiting fewer infiltrating leukocytes. By examining local and systemic cytokine responses to C. albicans and other standard inflammatory stimuli, we identify a crucial function of phagocytes in this enhanced resistance. Subcutaneous air pouch and systemic candidiasis models demonstrated that endogenous thrombospondin-1 enhances the early innate immune response against C. albicans and promotes activation of inflammatory macrophages (inducible nitric oxide synthase+, IL-6high, TNF-αhigh, IL-10low), release of the chemokines MIP-2, JE, MIP-1α, and RANTES, and CXCR2-driven polymorphonuclear leukocytes recruitment. However, thrombospondin-1 inhibited the phagocytic capacity of inflammatory leukocytes in vivo and in vitro, resulting in increased fungal burden in the kidney and increased mortality in wild type mice. Thus, thrombospondin-1 enhances the pathogenesis of disseminated candidiasis by creating an imbalance in the host immune response that ultimately leads to reduced phagocytic function, impaired fungal clearance, and increased mortality. Conversely, inhibitors of thrombospondin-1 may be useful drugs to improve patient recovery from disseminated candidiasis. PMID:23144964

  14. Sonic boom measurements from accelerating supersonic tracked sleds

    NASA Technical Reports Server (NTRS)

    Reed, J. W.

    1974-01-01

    Supersonic sled tests on the Sandia 1524-m (5000-ft) track generate sonic booms of sufficient intensity to allow some airblast measurements at distance scales not obtained from wind tunnel or flight tests. During acceleration, an emitted curved boom wave propagates to a caustic, or focus. Detailed measurements around these caustics may help to clarify the overpressure magnification which can occur from real aircraft operations. Six fixed pressure gages have been operated to document the general noise field, and a mobile array of twelve gages.

  15. A tracking code for injection and acceleration studies in synchrotrons

    SciTech Connect

    Lessner, E.; Symon, K. |

    1996-11-01

    CAPTURE-SPC is a Monte-Carlo-based tracking program that simulates the injection and acceleration processes in proton synchrotrons. The time evolution of a distribution of charged particles is implemented by a symplectic, second-order-accurate integration algorithm. The recurrence relations follow a time-stepping leap--frog method. The time-step can be varied optionally to reduce computer time. Space-charge forces are calculated by binning the phase-projected particle distribution. The statistical fluctuations introduced by the binning process are reduced by presmoothing the data by the cloud-in-cell method and by filtering. Both the bin size and amount of filtering can be varied during the acceleration cycle so that the bunch fine structure is retained while the short wavelength noise is attenuated. The initial coordinates of each macro particle together with its time of injection are retained throughout the calculations. This information is useful in determining low-loss injection schemes.

  16. Tracking accelerated aging of composites with ultrasonic attenuation measurements

    SciTech Connect

    Chinn, D.J.; Durbin, P.F.; Thomas, G.H.; Groves, S.E.

    1996-10-01

    Composite materials are steadily replacing traditional materials in many industries. For many carbon composite materials, particularly in aerospace applications, durability is a critical design parameter which must be accurately characterized. Lawrence Livermore National Laboratory (LLNL) and Boeing Commercial Airplane Group have established a cooperative research and development agreement (CRADA) to assist in the high speed research program at Boeing. LLNL`s expertise in fiber composites, computer modeling, mechanical testing, chemical analysis and nondestructive evaluation (ND) will contribute to the study of advanced composite materials in commercial aerospace applications. Through thermo-mechanical experiments with periodic chemical analysis and nondestructive evaluation, the aging mechanisms in several continuous fiber polymer composites will be studied. Several measurement techniques are being studied for their correlation with aging. This paper describes through-transmission ultrasonic attenuation measurements of isothermally aged composite materials and their use as a tracking parameter for accelerated aging.

  17. Leukocyte Telomere Length in Young Adults Born Preterm: Support for Accelerated Biological Ageing

    PubMed Central

    Smeets, Carolina C. J.; Codd, Veryan; Samani, Nilesh J.; Hokken-Koelega, Anita C. S.

    2015-01-01

    Background Subjects born preterm have an increased risk for age-associated diseases, such as cardiovascular disease in later life, but the underlying causes are largely unknown. Shorter leukocyte telomere length (LTL), a marker of biological age, is associated with increased risk of cardiovascular disease. Objectives To compare LTL between subjects born preterm and at term and to assess if LTL is associated with other putative cardiovascular risk factors at young adult age. Methods We measured mean LTL in 470 young adults. LTL was measured using a quantitative PCR assay and expressed as T/S ratio. We analyzed the influence of gestational age on LTL and compared LTL between subjects born preterm (n = 186) and at term (n = 284). Additionally, we analyzed the correlation between LTL and potential risk factors of cardiovascular disease. Results Gestational age was positively associated with LTL (r = 0.11, p = 0.02). Subjects born preterm had shorter LTL (mean (SD) T/S ratio = 3.12 (0.44)) than subjects born at term (mean (SD) T/S ratio = 3.25 (0.46)), p = 0.003). The difference remained significant after adjustment for gender and size at birth (p = 0.001). There was no association of LTL with any one of the putative risk factors analyzed. Conclusions Young adults born preterm have shorter LTL than young adults born at term. Although we found no correlation between LTL and risk for CVD at this young adult age, this biological ageing indicator may contribute to CVD and other adult onset diseases at a later age in those born preterm. PMID:26619005

  18. Accelerated leukocyte telomere erosion in schizophrenia: Evidence from the present study and a meta-analysis.

    PubMed

    Rao, Shuquan; Kota, Lakshmi Narayanan; Li, Zongchang; Yao, Yao; Tang, Jinsong; Mao, Canquan; Jain, Sanjeev; Xu, Yong; Xu, Qi

    2016-08-01

    Human telomeres consist of tandem nucleotide repeats (TTAGGG) and associated proteins, and telomere length (TL) is reduced progressively with cell division over the lifespan. Telomere erosion might be accelerated or prevented to varying degrees when exposure to serious medical illnesses. In previous studies, an association between TL decrease and schizophrenia has been extensively reported; however, the results remain largely controversial. To further investigate TL in schizophrenia patients and reconcile this controversy, we first measured leucocyte TL (LTL) in our samples (52 paranoid schizophrenia, 89 non-paranoid patients and 120 controls), and then conducted a comprehensive meta-analysis of the existing results of LTL in patients of schizophrenia compared to healthy subjects. Totally, 11 studies encompassing 1243 patients of schizophrenia and 1274 controls were included in the final meta-analysis model. In our samples, significant reduction of LTL in paranoid schizophrenia was observed compared to controls (F = 50.88, P < 0.001); whereas there was no significant difference in LTL between non-paranoid schizophrenia and controls (F = 0.842, P = 0.360). For meta-analysis, random-effects model showed significant LTL decrease in patients of schizophrenia when compared to controls (Z = 2.07, P = 0.039, SMD = -0.48, 95% CI = -0.94 to -0.03). Moreover, a marginal decrease in LTL was observed in medicated patients (Z = 1.92, P = 0.055, SMD = -0.58, 95% CI = -1.18-0.01) and those patients with poor response to antipsychotics (Z = 1.76, P = 0.078, SMD = -0.60, 95% CI = -1.27-0.07). In conclusion, we observed significant reduction of LTL in individuals with schizophrenia compared with controls. However, all the studies included in the meta-analysis were cross-sectional, and better controlled long-term studies are needed to replicate this result. PMID:27174400

  19. Fast Track Teaching: Beginning the Experiment in Accelerated Leadership Development

    ERIC Educational Resources Information Center

    Churches, Richard; Hutchinson, Geraldine; Jones, Jeff

    2009-01-01

    This article provides an overview of the development of the Fast Track teaching programme and personalised nature of the training and support that has been delivered. Fast Track teacher promotion rates are compared to national statistics demonstrating significant progression for certain groups, particularly women. (Contains 3 tables and 3 figures.)

  20. The Simpsons program 6-D phase space tracking with acceleration

    NASA Astrophysics Data System (ADS)

    Machida, S.

    1993-12-01

    A particle tracking code, Simpsons, in 6-D phase space including energy ramping has been developed to model proton synchrotrons and storage rings. We take time as the independent variable to change machine parameters and diagnose beam quality in a quite similar way as real machines, unlike existing tracking codes for synchrotrons which advance a particle element by element. Arbitrary energy ramping and rf voltage curves as a function of time are read as an input file for defining a machine cycle. The code is used to study beam dynamics with time dependent parameters. Some of the examples from simulations of the Superconducting Super Collider (SSC) boosters are shown.

  1. A parameter identification method combining acceleration search /Partan/ and continuous parameter tracking.

    NASA Technical Reports Server (NTRS)

    Jackson, G. A.

    1972-01-01

    A parameter identification method is presented which combines the best features of two well-established, existing methods: Continuous Parameter Tracking and Acceleration Search (Partan). In this paper the equations are developed for the general n-parameter identification problem, and results are given for a specific two parameter application.

  2. Waveband Analysis of Track Irregularities in High-Speed Railway from On-Board Acceleration Measurement

    NASA Astrophysics Data System (ADS)

    Lee, Jun Seok; Choi, Sunghoon; Kim, Sang-Soo; Kim, Young Guk; Kim, Seog Won; Park, Choonsoo

    This paper is focused on waveband analysis of the lateral and vertical track irregularities from the on-board acceleration measurement of in-service high-speed trains. The track irregularities play important roles to determine dynamic stability of vehicles and ride quality of passengers, so that their amplitude and wavelength should be monitored continuously and carefully. Measuring acceleration at the axle-box or bogie of the trains has been under consideration for low-cost implementation and robust to a harsh railway environment. To estimate the track irregularities, lateral and vertical vibration caused by the wheel/track interaction is measured by the axle-box and bogie mounted accelerometers of an in-service high-speed train. A Kalman filter is used to prevent unrealistic drifts in the estimation. By applying the waveband-pass and compensation filters to the estimated displacement, it is possible to estimate the track irregularities. A distance-wavelength representation is used to identify their waveband in an intuitive way. It is verified by comparing with a commercial track geometry measurement system. From their comparison, it confirms that the representation can produce a satisfactory result.

  3. Use of leukocyte and platelet-rich fibrin (L-PRF) in periodontally accelerated osteogenic orthodontics (PAOO): Clinical effects on edema and pain

    PubMed Central

    Munoz, Francisco; Jiménez, Constanza; Espinoza, Daniela; Vervelle, Alain; Beugnet, Jacques

    2016-01-01

    Background Demand for shorter treatment time is common in orthodontic patients. Periodontally Accelerated Osteogenic Orthodontics (PAOO) is a somewhat new surgical procedure which allows faster tooth movement via combining orthodontic forces with corticotomy and grafting of alveolar bone plates. Leukocyte and Platelet-Rich Fibrin (L-PRF) possess hard- and soft-tissue healing properties. Further, evidence of pain-inhibitory and anti-inflammatory potential is growing. Therefore, this study explores the feasibility, intra- and post-operative effects of using L-PRF in PAOO in terms of post-operative pain, inflammation, infection and post-orthodontic stability. Material and Methods A pilot prospective observational study involving a cohort of 11 patients was carried out. A Wilcko’s modified PAOO technique with L-PRF (incorporated into the graft and as covering membrane) was performed with informed consent. Post-surgical pain, inflammation and infection were recorded for 10 days post-operatively, while the overall orthodontic treatment and post-treatment stability were followed up to 2 years. Results Accelerated wound healing with no signs of infection or adverse reactions was evident. Post-surgical pain was either “mild” (45.5%) or “moderate” (54.5%). Immediate post-surgical inflammation was either “mild” (89.9%) or “moderate” (9.1%). Resolution began on day 4 where most patients experienced either “mild” or no inflammation (72.7% and 9.1%, respectively). Complete resolution was achieved in all patients by day 8. The average orthodontic treatment time was 9.3 months. All cases were deemed stable for 2 years. Conclusions L-PRF is simple and safe to use in PAOO. Combination with traditional bone grafts potentially accelerates wound healing and reduces post-surgical pain, inflammation, infection without interfering with tooth movement and/or post-orthodontic stability, over a 2 years period; thus alleviating the need for analgesics and anti

  4. Luminescent tracks of high-energy photoemitted electrons accelerated by plasmonic fields

    NASA Astrophysics Data System (ADS)

    Di Vece, Marcel; Giannakoudakis, Giorgos; Bjørkøy, Astrid; Tang, Wingjohn

    2015-12-01

    The emission of an electron from a metal nanostructure under illumination and its subsequent acceleration in a plasmonic field forms a platform to extend these phenomena to deposited nanoparticles, which can be studied by state-of-the-art confocal microscopy combined with femtosecond optical excitation. The emitted and accelerated electrons leave defect tracks in the immersion oil, which can be revealed by thermoluminescence. These photographic tracks are read out with the confocal microscope and have a maximum length of about 80 μm, which corresponds to a kinetic energy of about 100 keV. This energy is consistent with the energy provided by the intense laser pulse combined with plasmonic local field enhancement. The results are discussed within the context of the rescattering model by which electrons acquire more energy. The visualization of electron tracks originating from plasmonic field enhancement around a gold nanoparticle opens a new way to study with confocal microscopy both the plasmonic properties of metal nano objects as well as high energy electron interaction with matter.

  5. Real-time reprogrammable low-level image processing: edge detection and edge tracking accelerator

    NASA Astrophysics Data System (ADS)

    Meribout, M.; Hou, Kun M.

    1993-10-01

    Currently, in image processing, segmentation algorithms comprise between real time video rate processing and accurate results. In this paper, we present an efficient and not recursive algorithm filter originated from Deriche filter. This algorithm is implemented in hardware by using FPGA technology. Thus, it permits video rate edge detection. In addition, the FPGA board is used as an edge tracking accelerator, it allows us to greatly reduce execution time by avoiding scanning the whole image. We also present the architecture of our vision system dedicated to build 3D scene every 200 ms.

  6. A neutron track etch detector for electron linear accelerators in radiotherapy

    PubMed Central

    Vukovic, Branko; Faj, Dario; Poje, Marina; Varga, Maja; Radolic, Vanja; Miklavcic, Igor; Ivkovic, Ana; Planinic, Josip

    2010-01-01

    Background Electron linear accelerators in medical radiotherapy have replaced cobalt and caesium sources of radiation. However, medical accelerators with photon energies over 10 MeV generate undesired fast neutron contamination in a therapeutic X-ray photon beam. Photons with energies above 10 MeV can interact with the atomic nucleus of a high-Z material, of which the target and the head of an accelerator consist, and lead to the neutron ejection. Results and conclusions. Our neutron dosimeter, composed of the LR-115 track etch detector and boron foil BN-1 converter, was calibrated on thermal neutrons generated in the nuclear reactor of the Josef Stefan Institute (Slovenia), and applied to dosimetry of undesirable neutrons in photon radiotherapy by the linear accelerator 15 MV Siemens Mevatron. Having considered a high dependence of a cross-section between neutron and boron on neutron energy, and broad neutron spectrum in a photon beam, as well as outside the entrance door to maze of the Mevatron, we developed a method for determining the effective neutron detector response. A neutron dose rate in the photon beam was measured to be 1.96 Sv/h. Outside the Mevatron room the neutron dose rate was 0.62 μSv/h. PACS: 87.52. Ga; 87.53.St; 29.40.Wk. PMID:22933893

  7. Acceleration feedback control (AFC) enhanced by disturbance observation and compensation (DOC) for high precision tracking in telescope systems

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Cai, Hua-Xiang; Huang, Yong-Mei; Ge, Liang; Tang, Tao; Su, Yan-Rui; Liu, Xiang; Li, Jin-Ying; He, Dong; Du, Sheng-Ping; Ling, Yu

    2016-08-01

    In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observation and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Telescope systems usually suffer some uncertain disturbances, such as wind load, nonlinear friction and other unknown disturbances. To ensure tracking precision, an acceleration feedback loop which can increase the stiffness of such a system is introduced. Moreover, to further improve the tracking precision, we introduce the DOC method which can accurately estimate the disturbance and compensate it. Furthermore, the analysis of tracking accuracy used by this method is proposed. Finally, a few comparative experimental results show that the proposed control method has excellent performance for reducing the tracking error of a telescope system.

  8. Track Structure and the Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage

    NASA Technical Reports Server (NTRS)

    George, K.; Hada, M.; Chappell, L.; Cucinotta, F. A.

    2011-01-01

    Track structure models predict that at a fixed value of LET, particles with lower charge number, Z will have a higher biological effectiveness compared to particles with a higher Z. In this report we investigated how track structure effects induction of chromosomal aberration in human cells. Human lymphocytes were irradiated in vitro with various energies of accelerated iron, silicon, neon, or titanium ions and chromosome damage was assessed in using three color FISH chromosome painting in chemically induced PCC samples collected a first cell division post irradiation. The LET values for these ions ranged from 30 to195 keV/micron. Of the particles studied, Neon ions have the highest biological effectiveness for induction of total chromosome damage, which is consistent with track structure model predictions. For complex-type exchanges 64 MeV/ u Neon and 450 MeV/u Iron were equally effective and induced the most complex damage. In addition we present data on chromosomes exchanges induced by six different energies of protons (5 MeV/u to 2.5 GeV/u). The linear dose response term was similar for all energies of protons suggesting that the effect of the higher LET at low proton energies is balanced by the production of nuclear secondaries from the high energy protons.

  9. Evaluation of Linear Accelerator Gating With Real-Time Electromagnetic Tracking

    SciTech Connect

    Smith, Ryan L.; Lechleiter, Kristen; Malinowski, Kathleen; Shepard, D.M.; Housley, D.J.; Afghan, M.; Newell, Jeff; Petersen, Jay; Sargent, Brian; Parikh, Parag

    2009-07-01

    Purpose: Intrafraction organ motion can produce dosimetric errors in radiotherapy. Commonly, the linear accelerator is gated using real-time breathing phase obtained by way of external sensors. However, the external anatomy does not always correlate well with the internal position. We examined a beam gating technique using signals from implanted wireless transponders that provided real-time feedback on the tumor location without an imaging dose to the patient. Methods and Materials: An interface was developed between Calypso Medical's four-dimensional electromagnetic tracking system and a Varian Trilogy linear accelerator. A film phantom was mounted on a motion platform programmed with lung motion trajectories. Deliveries were performed when the beam was gated according to the signal from the wireless transponders. The dosimetric advantages of beam gating and the system latencies were quantified. Results: Beam gating using on internal position monitoring provided up to a twofold increase in the dose gradients. The percentage of points failing to be within {+-}10 cGy of the planned dose (maximal dose, {approx}200 cGy) was 3.4% for gating and 32.1% for no intervention in the presence of motion. The mean latencies between the transponder position and linear accelerator modulation were 75.0 {+-}12.7 ms for beam on and 65.1 {+-} 12.9 ms for beam off. Conclusion: We have presented the results from a novel method for gating the linear accelerator using trackable wireless internal fiducial markers without the use of ionizing radiation for imaging. The latencies observed were suitable for gating using electromagnetic fiducial markers, which results in dosimetric improvements for irradiation in the presence of motion.

  10. Erosion by acid rain, accelerating the tracking of polystyrene insulating material

    NASA Astrophysics Data System (ADS)

    Wang, X.; Chen, L.; Yoshimura, N.

    2000-05-01

    Because outdoor insulating materials in service are subjected to numerous wet and dry cycles, it is necessary to establish their performance in acid rain. The erosion effect of acid rain on atactic polystyrene insulating material is investigated using accelerated ageing by artificial acid rain. The degradation mechanisms of material structure and tracking resistance are discussed. The experimental results reported here show that the erosion of acid rain causes the degradation of the surface chemical and physical structures of polystyrene (PS) material so that the surface conductivity of aged material increases. Under electrical stress, the surface discharge current increases, and the local surface is deteriorated so that the tracking is initiated earlier and the material rapidly fails. The degradation rate of PS material in acid rain varies as function of the ion concentration, pH and conductivity of acid rain. Only the severe acid rain of high acidity and conductivity can exert an influence on PS insulating material. The concentration of actual rainwater is insufficient to lead to obvious erosion on PS insulation. PS insulation could resist on the erosion of normal acid rainwater. Even though clear degradation occurs with strong acid rain, PS could behave quite well in mild acid rain conditions.

  11. The application of front tracking to the simulation of shock refractions and shock accelerated interface mixing

    SciTech Connect

    Sharp, D.H.; Grove, J.W.; Yang, Y.; Boston, B.; Holmes, R.; Zhang, Q.; Glimm, J.

    1993-08-01

    The mixing behavior of two or more fluids plays an important role in a number of physical processes and technological applications. The authors consider two basic types of mechanical (i.e., non-diffusive) fluid mixing. If a heavy fluid is suspended above a lighter fluid in the presence of a gravitational field, small perturbations at the fluid interface will grow. This process is known as the Rayleigh-Taylor instability. One can visualize this instability in terms of bubbles of the light fluid rising into the heavy fluid, and fingers (spikes) of the heavy fluid falling into the light fluid. A similar process, called the Richtmyer-Meshkov instability occurs when an interface is accelerated by a shock wave. These instabilities have several common features. Indeed, Richtmyer`s approach to understanding the shock induced instability was to view that process as resulting from an acceleration of the two fluids by a strong gravitational field acting for a short time. Here, the authors report new results on the Rayleigh-Taylor and Richtmyer-Meshkov instabilities. Highlights include calculations of Richtmyer-Meshkov instabilities in curved geometries without grid orientation effects, improved agreement between computations and experiments in the case of Richtmyer-Meshkov instabilities at a plane interface, and a demonstration of an increase in the Rayleigh-Taylor mixing layer growth rate with increasing compressibility, along with a loss of universality of this growth rate. The principal computational tool used in obtaining these results was a code based on the front tracking method.

  12. Pelegant : a parallel accelerator simulation code for electron generation and tracking.

    SciTech Connect

    Wang, Y.; Borland, M. D.; Accelerator Systems Division

    2006-01-01

    elegant is a general-purpose code for electron accelerator simulation that has a worldwide user base. Recently, many of the time-intensive elements were parallelized using MPI. Development has used modest Linux clusters and the BlueGene/L supercomputer at Argonne National Laboratory. This has provided very good performance for some practical simulations, such as multiparticle tracking with synchrotron radiation and emittance blow-up in the vertical rf kick scheme. The effort began with development of a concept that allowed for gradual parallelization of the code, using the existing beamline-element classification table in elegant. This was crucial as it allowed parallelization without major changes in code structure and without major conflicts with the ongoing evolution of elegant. Because of rounding error and finite machine precision, validating a parallel program against a uniprocessor program with the requirement of bitwise identical results is notoriously difficult. We will report validating simulation results of parallel elegant against those of serial elegant by applying Kahan's algorithm to improve accuracy dramatically for both versions. The quality of random numbers in a parallel implementation is very important for some simulations. Some practical experience with generating parallel random numbers by offsetting the seed of each random sequence according to the processor ID will be reported.

  13. The NREL outdoor accelerated-weathering tracking system and photovoltaic module exposure results

    NASA Astrophysics Data System (ADS)

    Basso, Thomas S.

    1999-03-01

    This paper describes the Outdoor Accelerated-weathering Tracking System (OATS) and interim results for the first OATS study on photovoltaic (PV) modules. With two test planes measuring 1.52×1.83 m, OATS provides a unique solar-concentrating exposure capability. Test sample temperatures are moderated by air blowers. Water spray capability exists for wetting samples. The OATS two-axis tracker points to the sun using software calculations. Non-imaging aluminum reflectors give a nominal clear-sky optical concentration ratio of three. Field-qualification measurements in the test plane under reflector conditions showed its relative irradiance non-uniformity was ±15% for a clear-sky summer day with ± 75 mm as the smallest distance for that non-uniformity. Exposure studies began in November 1997 on seven pairs of commercially available ribbon silicon, crystalline silicon and amorphous silicon PV modules kept at constant resistive load. The modules were periodically removed from OATS for visual inspection and solar simulator performance measurements. There were no module failures. This PV module study is ongoing and later results will be compared to other testing techniques. Through July 1998, the modules under reflector conditions received 392 MJ/m2 of total ultraviolet (TUV) exposure. That was 2.07 times the TUV exposure compared to a south-facing fixed array tilted 40° up from horizontal at NREL. Similarly, the modules in the test plane under the covered reflectors received 1.04 times the fixed array TUV exposure. For the test plane under the covered reflectors there was a loss of 13% TUV exposure attributed to the reflectors blocking some of the diffuse-sky UV light. Also through July 1998, the OATS sunlight availability measured 95% compared to the cumulative global normal exposure at the NREL Solar Radiation Research Laboratory (SRRL). The OATS sunlight availability losses included downtime when the PV modules were removed, and when there were OATS tracking

  14. A Framework for 3D Model-Based Visual Tracking Using a GPU-Accelerated Particle Filter.

    PubMed

    Brown, J A; Capson, D W

    2012-01-01

    A novel framework for acceleration of particle filtering approaches to 3D model-based, markerless visual tracking in monocular video is described. Specifically, we present a methodology for partitioning and mapping the computationally expensive weight-update stage of a particle filter to a graphics processing unit (GPU) to achieve particle- and pixel-level parallelism. Nvidia CUDA and Direct3D are employed to harness the massively parallel computational power of modern GPUs for simulation (3D model rendering) and evaluation (segmentation, feature extraction, and weight calculation) of hundreds of particles at high speeds. The proposed framework addresses the computational intensity that is intrinsic to all particle filter approaches, including those that have been modified to minimize the number of particles required for a particular task. Performance and tracking quality results for rigid object and articulated hand tracking experiments demonstrate markerless, model-based visual tracking on consumer-grade graphics hardware with pixel-level accuracy up to 95 percent at 60+ frames per second. The framework accelerates particle evaluation up to 49 times over a comparable CPU-only implementation, providing an increased particle count while maintaining real-time frame rates. PMID:21301027

  15. Coagulant Activity of Leukocytes. TISSUE FACTOR ACTIVITY

    PubMed Central

    Niemetz, J.

    1972-01-01

    Peritoneal leukocytes harvested from rabbits which have received two spaced doses of endotoxin have significantly greater (10-fold) coagulant activity than leukocytes from control rabbits. The coagulant activity accelerates the clotting of normal plasma and activates factor X in the presence of factor VII and calcium and is therefore regarded as tissue factor. A total of 40-80 mg tissue factor activity was obtained from the peritoneal cavity of single endotoxin-treated rabbits. In leukocyte subcellular fractions, separated by centrifugation, the specific tissue factor activity sedimented mainly at 14,500 g and above. The procoagulant activity was destroyed after heating for 10 min at 65°C but was preserved at lower temperatures. Polymyxin B, when given with the first dose of endotoxin, reduced both the number of peritoneal leukocytes and their tissue factor activity by two-thirds. When given immediately before the second dose of endotoxin, polymyxin B had no inhibitory effect. PMID:4333021

  16. MV image-based dynamic MLC tracking of a NiTi stent in pig lungs on a linear accelerator

    PubMed Central

    Poulsen, Per R; Carl, Jesper; Nielsen, Jane; Nielsen, Martin S; Thomsen, Jakob B; Jensen, Henrik K; Kjærgaard, Benedict; Zepernick, Peter R; Worm, Esben; Fledelius, Walther; Cho, Byungchul; Sawant, Amit; Ruan, Dan; Keall, Paul J

    2011-01-01

    Purpose: To investigate the accuracy and potential limitations of MV image-based dynamic MLC tracking in a porcine model on a linear accelerator. Methods and Materials: A thermo-expandable NiTi stent designed for kV x-ray visualization of lung lesions was inserted into the bronchia of three anaesthetized Göttingen minipigs. A 4DCT scan was used for planning a 5-field conformal treatment with circular MLC apertures. A 22.5Gy single fraction treatment was delivered to the pigs. The peak-to-peak stent motion was 3-8mm with breathing periods of 1.2-4 seconds. Prior to treatment, x-ray images were used for image-guided setup based on the stent. During treatment delivery, continuous portal images were acquired at 7.5Hz. The stent was segmented in the images and used for continuous adaptation of the MLC aperture. Offline, the tracking error in beam’s eye view of the MV beam was calculated for each image as the difference between the MLC aperture center and the segmented stent position. The standard deviations of the systematic error Σ and the random error σ were determined and compared with the would-be errors for a non-tracking treatment with pre-treatment image-guided setup. Results: Reliable stent segmentation was obtained for 11 out of 15 fields. Segmentation failures occurred when image contrast was dominated by overlapping anatomical structures (ribs, diaphragm) rather than by the stent, which was designed for kV rather than MV x-ray visibility. For the 11 fields with reliable segmentation, Σ was 0.5mm/0.4mm in the two imager directions, while σ was 0.5mm/1.1mm. Without tracking, Σ and σ would have been 1.7mm/1.4mm and 0.8mm/1.4mm, respectively. Conclusion: For the first time, in vivo DMLC tracking has been demonstrated on a linear accelerator showing the potential for improved targeting accuracy. The study mimicked the envisioned patient workflow of future patient treatments. Clinical implementation of MV image-based tracking would require markers designed

  17. Leukocyte relaxation properties.

    PubMed Central

    Sung, K L; Dong, C; Schmid-Schönbein, G W; Chien, S; Skalak, R

    1988-01-01

    Study of the mechanical properties of leukocytes is useful to understand their passage through narrow capillaries and interaction with other cells. Leukocytes are known to be viscoelastic and their properties have been established by micropipette aspiration techniques. Here, the recovery of leukocytes to their normal spherical form is studied after prolonged deformation in a pipette which is large enough to permit complete entry of the leukocyte. The recovery history is characterized by the time history of the major diameter (d1) and minor diameter (d2). When the cell is removed from the pipette, it shows initially a small rapid recoil followed by a slower asymptotic recovery to the spherical shape. In the presence of cell activation and formation of pseudopods, the time history for recovery is prolonged compared with passive cell recovery. If a protopod pre-existed during the holding period, the recovery only begins when the protopod starts to retract. Images FIGURE 1 PMID:3207829

  18. Studies of the chromatic properties and dynamic aperture of the BNL colliding-beam accelerator. [PATRICIA particle tracking code

    SciTech Connect

    Dell, G.F.

    1983-01-01

    The PATRICIA particle tracking program has been used to study chromatic effects in the Brookhaven CBA (Colliding Beam Accelerator). The short term behavior of particles in the CBA has been followed for particle histories of 300 turns. Contributions from magnet multipoles characteristic of superconducting magnets and closed orbit errors have been included in determining the dynamic aperture of the CBA for on and off momentum particles. The width of the third integer stopband produced by the temperature dependence of magnetization induced sextupoles in the CBA cable dipoles is evaluated for helium distribution systems having periodicity of one and six. The stopband width at a tune of 68/3 is naturally zero for the system having a periodicity of six and is approx. 10/sup -4/ for the system having a periodicity of one. Results from theory are compared with results obtained with PATRICIA; the results agree within a factor of slightly more than two.

  19. Accelerating D&D at Fernald: The fast track remediation design/bid package

    SciTech Connect

    Houser, S.M.; Albertin, M.F.; Borgman, T.D.; Zebick, W.A.

    1995-01-31

    The Fernald Environmental Management Project is a Department Of Energy (DOE) facility near Cincinnati, Ohio which provided high purity uranium metal products to support United States defense programs. Production operations were halted in 1989 to focus available resources on environmental restoration activities at the facility. Operable Unit 3 (OU3) is the designation given to the production area and production-associated facilities and equipment, including, but not limited to, all above and below ground structures, equipment, and utilities. In late spring of 1994, two decisions were made that established the long range strategy on how remedial designs (RD) and the bidding of remedial actions (RA) are approached for the decontamination and decommissioning (D&D) of the Fernald facilities. The first was to fast track the remediation design and bidding process for the first three D&D packages; and the second was to use standard performance specifications to streamline the decontamination and decommissioning process. This paper describes these strategies, identifies the key elements involved, and discusses the lessons learned that were associated with the approaches. A brief synopsis of these elements follows: (1) A facility complex grouping facilities into blocks of work was used for bid packages. (2) A task force approach involving required functional organizations was used to fast track the design and bidding process. (3) Standard Performance Specifications have been developed for each task to establish minimum acceptable criteria and provide the subcontractor flexibility. This approach also dramatically decreases costs for future D&D packages. (4) A key feature of value engineering has been the use of construction methods and techniques to drive the D&D cost significantly lower. (5) The bid package was structured around a modified IFB approach. This provides the successful bidder the opportunity to incorporate innovative ideas within the performance.

  20. Measurements of photo-neutrons from a medical linear accelerator using CR-39 plastic nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Monson, Jonathan Michael

    Photo-neutrons are produced when x-ray energies exceed 7 MeV. Photo-neutron production varies depending on x-ray beam energy. CR-39 PNTDs were used in this study to measure the neutron absorbed dose and dose equivalent produced by a Varian Clinac 23EX for x-ray beams of 6 and 18 MVp and with a Varian Trilogy using an x-ray beam of 10 MVp. Neutron absorbed dose and dose equivalent were measured at 100 cm SSD at 0, 20, and 40 cm off-axis from the primary beam in air. Using a polyethylene phantom the neutron absorbed dose and dose equivalent were measured at 100 cm SSD from the top of the phantom at 0, 5, and 10 cm from the surface, in the beam central axis and off-axis distances of 20 and 40 cm at a depth of 10 cm. The neutron absorbed dose and dose equivalent from medical linear accelerators have been measured from the LET spectrum of recoiled tracks produced in the CR-39 PNTDs for high energy neutrons (1-20 MeV) and the neutron dose equivalent for low energy (< 1 MeV) neutrons were measured using TRNDs. In this study, the experimentally measured absorbed dose and dose equivalent from photo-neutrons produced in a common medical linear accelerator operating at energies 10 and 18 MVp range from 0.2 microGy n/Gyx and 2 microSv n/Gyx to 495 microGy n/Gyx and 5500 microSv n/Gyx respectively. The neutron absorbed dose for the 6 MVp x-ray beam was measured to be 0 microGyn/Gyx. Low energy neutrons accounted for less than 1% of the neutron dose equivalent. Those detectors exposed inside of the phantom measured a higher contribution from high LET (> 100 keV/microm) particles than those detectors exposed in air.

  1. Biomechanics of leukocyte rolling.

    PubMed

    Sundd, Prithu; Pospieszalska, Maria K; Cheung, Luthur Siu-Lun; Konstantopoulos, Konstantinos; Ley, Klaus

    2011-01-01

    Leukocyte rolling on endothelial cells and other P-selectin substrates is mediated by P-selectin binding to P-selectin glycoprotein ligand-1 expressed on the tips of leukocyte microvilli. Leukocyte rolling is a result of rapid, yet balanced formation and dissociation of selectin-ligand bonds in the presence of hydrodynamic shear forces. The hydrodynamic forces acting on the bonds may either increase (catch bonds) or decrease (slip bonds) their lifetimes. The force-dependent 'catch-slip' bond kinetics are explained using the 'two pathway model' for bond dissociation. Both the 'sliding-rebinding' and the 'allosteric' mechanisms attribute 'catch-slip' bond behavior to the force-induced conformational changes in the lectin-EGF domain hinge of selectins. Below a threshold shear stress, selectins cannot mediate rolling. This 'shear-threshold' phenomenon is a consequence of shear-enhanced tethering and catch bond-enhanced rolling. Quantitative dynamic footprinting microscopy has revealed that leukocytes rolling at venular shear stresses (>0.6 Pa) undergo cellular deformation (large footprint) and form long tethers. The hydrodynamic shear force and torque acting on the rolling cell are thought to be synergistically balanced by the forces acting on tethers and stressed microvilli, however, their relative contribution remains to be determined. Thus, improvement beyond the current understanding requires in silico models that can predict both cellular and microvillus deformation and experiments that allow measurement of forces acting on individual microvilli and tethers. PMID:21515934

  2. Towards a computational model of leukocyte adhesion cascade: Leukocyte rolling

    NASA Astrophysics Data System (ADS)

    Khismatullin, Damir

    2005-11-01

    Recruitment of leukocytes into sites of acute and chronic inflammation is a vital component of the innate immune response in humans and plays an important role in cardiovascular diseases, such as ischemia-reperfusion injury and atherosclerosis. Leukocytes extravasate into the inflamed tissue through a multi-step process called "leukocyte adhesion cascade", which involves initial contact of a leukocyte with activated endothelium (tethering), leukocyte rolling, firm adhesion, and transendothelial migration. Recently we developed a fully three-dimensional CFD model of receptor-mediated leukocyte adhesion to endothelium in a parallel-plate flow chamber. The model treats the leukocyte as a viscoelastic cell with the nucleus located in the intracellular space and cylindrical microvilli distributed over the cell membrane. Leukocyte-endothelial adhesion is assumed to be mediated by adhesion molecules expressed on the tips of cell microvilli and on endothelium. We show that the model can predict both shape changes and velocities of rolling leukocytes under physiological flow conditions. Results of this study also indicate that viscosity of the cytoplasm is a critical parameter of leukocyte adhesion, affecting the cell's ability to roll on endothelium. This work is supported by NIH Grant HL- 57446 and NCSA Grant BCS040006 and utilized the NCSA IBM p690.

  3. Accelerated removal of antibody-coated red blood cells from the circulation is accurately tracked by a biotin label

    PubMed Central

    Mock, Donald M.; Lankford, Gary L.; Matthews, Nell I.; Burmeister, Leon F.; Kahn, Daniel; Widness, John A.; Strauss, Ronald G.

    2013-01-01

    BACKGROUND Safe, accurate methods to reliably measure circulating red blood cell (RBC) kinetics are critical tools to investigate pathophysiology and therapy of anemia, including hemolytic anemias. This study documents the ability of a method using biotin-labeled RBCs (BioRBCs) to measure RBC survival (RCS) shortened by coating with a highly purified monomeric immunoglobulin G antibody to D antigen. STUDY DESIGN AND METHODS Autologous RBCs from 10 healthy D+ subjects were labeled with either biotin or 51Cr (reference method), coated (opsonized) either lightly (n = 4) or heavily (n = 6) with anti-D, and transfused. RCS was determined for BioRBCs and for 51Cr independently as assessed by three variables: 1) posttransfusion recovery at 24 hours (PTR24) for short-term RCS; 2) time to 50% decrease of the label (T50), and 3) mean potential life span (MPL) for long-term RCS. RESULTS BioRBCs tracked both normal and shortened RCS accurately relative to 51Cr. For lightly coated RBCs, mean PTR24, T50, and MPL results were not different between BioRBCs and 51Cr. For heavily coated RBCs, both short-term and long-term RCS were shortened by approximately 17 and 50%, respectively. Mean PTR24 by BioRBCs (84 ± 18%) was not different from 51Cr (81 ± 10%); mean T50 by BioRBCs (23 ± 17 days) was not different from 51Cr (22 ± 18 days). CONCLUSION RCS shortened by coating with anti-D can be accurately measured by BioRBCs. We speculate that BioRBCs will be useful for studying RCS in conditions involving accelerated removal of RBCs including allo- and autoimmune hemolytic anemias. PMID:22023312

  4. Recent advances in microscopic techniques for visualizing leukocytes in vivo

    PubMed Central

    Jain, Rohit; Tikoo, Shweta; Weninger, Wolfgang

    2016-01-01

    Leukocytes are inherently motile and interactive cells. Recent advances in intravital microscopy approaches have enabled a new vista of their behavior within intact tissues in real time. This brief review summarizes the developments enabling the tracking of immune responses in vivo. PMID:27239292

  5. Recent advances in microscopic techniques for visualizing leukocytes in vivo.

    PubMed

    Jain, Rohit; Tikoo, Shweta; Weninger, Wolfgang

    2016-01-01

    Leukocytes are inherently motile and interactive cells. Recent advances in intravital microscopy approaches have enabled a new vista of their behavior within intact tissues in real time. This brief review summarizes the developments enabling the tracking of immune responses in vivo. PMID:27239292

  6. Computational modeling of leukocyte adhesion cascade (LAC)

    NASA Astrophysics Data System (ADS)

    Sarkar, Kausik

    2005-11-01

    In response to an inflammation in the body, leukocytes (white blood cell) interact with the endothelium (interior wall of blood vessel) through a series of steps--capture, rolling, adhesion and transmigration--critical for proper functioning of the immune system. We are numerically simulating this process using a Front-tracking finite-difference method. The viscoelastcity of the cell membrane, cytoplasm and nucleus are incorporated and allowed to change with time in response to the cell surface molecular chemistry. The molecular level forces due to specific ligand-receptor interactions are accounted for by stochastic spring-peeling model. Even though leukocyte rolling has been investigated through various models, the transitioning through subsequent steps, specifically firm adhesion and transmigration through endothelial layer, has not been modeled. The change of viscoelastic properties due to the leukocyte activation is observed to play a critical role in mediating the transition from rolling to transmigration. We will provide details of our approach and discuss preliminary results.

  7. Cryopreservation of Human Mucosal Leukocytes

    PubMed Central

    Shu, Zhiquan; Levy, Claire N.; Ferre, April L.; Hartig, Heather; Fang, Cifeng; Lentz, Gretchen; Fialkow, Michael; Kirby, Anna C.; Adams Waldorf, Kristina M.; Veazey, Ronald S.; Germann, Anja; von Briesen, Hagen; McElrath, M. Juliana; Dezzutti, Charlene S.; Sinclair, Elizabeth; Baker, Chris A. R.; Shacklett, Barbara L.; Gao, Dayong; Hladik, Florian

    2016-01-01

    Background Understanding how leukocytes in the cervicovaginal and colorectal mucosae respond to pathogens, and how medical interventions affect these responses, is important for developing better tools to prevent HIV and other sexually transmitted infections. An effective cryopreservation protocol for these cells following their isolation will make studying them more feasible. Methods and Findings To find an optimal cryopreservation protocol for mucosal mononuclear leukocytes, we compared cryopreservation media and procedures using human vaginal leukocytes and confirmed our results with endocervical and colorectal leukocytes. Specifically, we measured the recovery of viable vaginal T cells and macrophages after cryopreservation with different cryopreservation media and handling procedures. We found several cryopreservation media that led to recoveries above 75%. Limiting the number and volume of washes increased the fraction of cells recovered by 10–15%, possibly due to the small cell numbers in mucosal samples. We confirmed that our cryopreservation protocol also works well for both endocervical and colorectal leukocytes. Cryopreserved leukocytes had slightly increased cytokine responses to antigenic stimulation relative to the same cells tested fresh. Additionally, we tested whether it is better to cryopreserve endocervical cells on the cytobrush or in suspension. Conclusions Leukocytes from cervicovaginal and colorectal tissues can be cryopreserved with good recovery of functional, viable cells using several different cryopreservation media. The number and volume of washes has an experimentally meaningful effect on the percentage of cells recovered. We provide a detailed, step-by-step protocol with best practices for cryopreservation of mucosal leukocytes. PMID:27232996

  8. Superoxide production by phagocytic leukocytes.

    PubMed

    Drath, D B; Karnovsky, M L

    1975-01-01

    Mononuclear phagocytic leukocytes, as well as polymorphonuclear leukocytes, produce and release superoxide at rest, and this is stimulated by phagocytosis. Of the mouse monocytic cells studied, alveolar macrophages released the largest amounts of superoxide during phagocytosis, followed by normal peritoneal macrophages. Casein-elicited and "activated" macrophages released smaller quantities. In the guinea pig, polymorphonuclear leukocytes and casein-elicited macrophages were shown to release superoxide during phagocytosis whereas alveolar macrophages did not. Superoxide release accounted for only a small fraction of the respiratory burst of phagocytosis in all but the normal mouse peritoneal macrophage, the guinea pig polymorphonuclear leukocyte, and probably the mouse alveolar macrophage. There are obviously considerable species differences in O2-release by various leukocytes that might reflect both the production and/or destruction (e.g. by dismutase) of that substance. PMID:804030

  9. Leukocyte biophysics. An invited review.

    PubMed

    Schmid-Schönbein, G W

    1990-10-01

    The biophysical properties of leukocytes in the passive and active state are discussed. In the passive unstressed state, leukocytes are spherical with numerous membrane folds. Passive leukocytes exhibit viscoelastic properties, and the stress is carried largely by the cell cytoplasm and the nucleus. The membrane is highly deformable in shearing and bending, but resists area expansion. Membrane tension can usually be neglected but plays a role in cases of large deformation when the membrane becomes unfolded. The constant membrane area constraint is a determinant of phagocytic capacity, spreading of cells, and passage through narrow pores. In the active state, leukocytes undergo large internal cytoplasmic deformation, pseudopod projection, and granule redistribution. Several different measurements for assessment of biophysical properties and the internal cytoplasmic deformation in form of strain and strain rate tensors are presented. The current theoretical models for active cytoplasmic motion in leukocytes are discussed in terms of specific macromolecular reactions. PMID:1705479

  10. Multiple Model Adaptive Two-Step Filter and Motion Tracking Sliding-Mode Guidance for Missiles with Time Lag in Acceleration

    NASA Astrophysics Data System (ADS)

    Zhou, Di; Zhang, Yong-An; Duan, Guang-Ren

    The two-step filter has been combined with a modified Sage-Husa time-varying measurement noise statistical estimator, which is able to estimate the covariance of measurement noise on line, to generate an adaptive two-step filter. In many practical applications such as the bearings-only guidance, some model parameters and the process noise covariance are also unknown a priori. Based on the adaptive two-step filter, we utilize multiple models in the first-step filtering as well as in the time update of the second-step filtering to handle the uncertainties of model parameters and process noise covariance. In each timestep of the multiple model filtering, probabilistic weights punishing the estimates of first-step state from different models, and their associated covariance matrices are acquired according to Bayes’ rule. The weighted sum of the estimates of first-step state and that of the associated covariance matrices are extracted as the ultimate estimate and covariance of the first-step state, and are used as measurement information for the measurement update of the second-step state. Thus there is still only one iteration process and no apparent enhancement of computation burden. A motion tracking sliding-mode guidance law is presented for missiles with non-negligible delays in actual acceleration. This guidance law guarantees guidance accuracy and is able to enhance observability in bearings-only tracking. In bearings-only cases, the multiple model adaptive two-step filter is applied to the motion tracking sliding-mode guidance law, supplying relative range, relative velocity, and target acceleration information. In simulation experiments satisfactory filtering and guidance results are obtained, even if the filter runs into unknown target maneuvers and unknown time-varying measurement noise covariance, and the guidance law has to deal with a large time lag in acceleration.

  11. Field calculations, single-particle tracking, and beam dynamics with space charge in the electron lens for the Fermilab Integrable Optics Test Accelerator

    SciTech Connect

    Noll, Daniel; Stancari, Giulio

    2015-11-17

    An electron lens is planned for the Fermilab Integrable Optics Test Accelerator as a nonlinear element for integrable dynamics, as an electron cooler, and as an electron trap to study space-charge compensation in rings. We present the main design principles and constraints for nonlinear integrable optics. A magnetic configuration of the solenoids and of the toroidal section is laid out. Singleparticle tracking is used to optimize the electron path. Electron beam dynamics at high intensity is calculated with a particle-in-cell code to estimate current limits, profile distortions, and the effects on the circulating beam. In the conclusions, we summarize the main findings and list directions for further work.

  12. The Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage: Track Structure Effects and Cytogenetic Signatures of High-LET Exposure

    NASA Technical Reports Server (NTRS)

    George, K.; Hada, M.; Chappell, L.; Cucinotta, F. A.

    2012-01-01

    Track structure models predict that at a fixed value of LET, particles with lower charge number, Z will have a higher biological effectiveness compared to particles with a higher Z. In this report we investigated how track structure effects induction of chromosomal aberration in human cells. Human lymphocytes were irradiated in vitro with various energies of accelerated iron, silicon, neon, or titanium ions and chromosome damage was assessed in using three color FISH chromosome painting in chemically induced PCC samples collected a first cell division post irradiation. The LET values for these ions ranged from 30 to 195 keV/micrometers. Of the particles studied, Neon ions have the highest biological effectiveness for induction of total chromosome damage, which is consistent with track structure model predictions. For complex-type exchanges 64 MeV/ u Neon and 450 MeV/u Iron were equally effective and induced the most complex damage. In addition we present data on chromosomes exchanges induced by six different energies of protons (5 MeV/u to 2.5 GeV/u). The linear dose response term was similar for all energies of protons suggesting that the effect of the higher LET at low proton energies is balanced by the production of nuclear secondaries from the high energy protons. All energies of protons have a much higher percentage of complex-type chromosome exchanges than gamma rays, signifying a cytogenetic signature for proton exposures.

  13. Megavoltage Image-Based Dynamic Multileaf Collimator Tracking of a NiTi Stent in Porcine Lungs on a Linear Accelerator

    SciTech Connect

    Poulsen, Per R.; Carl, Jesper; Nielsen, Jane; Nielsen, Martin S.; Thomsen, Jakob B.; Jensen, Henrik K.; Kjaergaard, Benedict; Zepernick, Peter R.; Worm, Esben; Fledelius, Walther; Cho, Byungchul; Sawant, Amit; Ruan, Dan; Keall, Paul J.

    2012-02-01

    Purpose: To investigate the accuracy and potential limitations of MV image-based dynamic multileaf collimator (DMLC) tracking in a porcine model on a linear accelerator. Methods and Materials: A thermo-expandable NiTi stent designed for kilovoltage (kV) X-ray visualization of lung lesions was inserted into the bronchia of three anaesthetized Goettingen minipigs. A four-dimensional computed tomography scan was used for planning a five-field conformal treatment with circular multileaf collimator (MLC) apertures. A 22.5 Gy single fraction treatment was delivered to the pigs. The peak-to-peak stent motion was 3 to 8 mm, with breathing periods of 1.2 to 4 s. Before treatment, X-ray images were used for image-guided setup based on the stent. During treatment delivery, continuous megavoltage (MV) portal images were acquired at 7.5 Hz. The stent was segmented in the images and used for continuous adaptation of the MLC aperture. Offline, the tracking error in beam's eye view of the treatment beam was calculated for each MV image as the difference between the MLC aperture center and the segmented stent position. The standard deviations of the systematic error {Sigma} and the random error {sigma} were determined and compared with the would-be errors for a nontracking treatment with pretreatment image-guided setup. Results: Reliable stent segmentation was obtained for 11 of 15 fields. Segmentation failures occurred when image contrast was dominated by overlapping anatomical structures (ribs, diaphragm) rather than by the stent, which was designed for kV rather than MV X-ray visibility. For the 11 fields with reliable segmentation, {Sigma} was 0.5 mm/0.4 mm in the two imager directions, whereas {sigma} was 0.5 mm/1.1 mm. Without tracking, {Sigma} and {sigma} would have been 1.7 mm/1.4 mm and 0.8 mm/1.4 mm, respectively. Conclusion: For the first time, in vivo DMLC tracking has been demonstrated on a linear accelerator showing the potential for improved targeting accuracy. The

  14. Development and application of compact and on-chip electron linear accelerators for dynamic tracking cancer therapy and DNA damage/repair analysis

    NASA Astrophysics Data System (ADS)

    Uesaka, M.; Demachi, K.; Fujiwara, T.; Dobashi, K.; Fujisawa, H.; Chhatkuli, R. B.; Tsuda, A.; Tanaka, S.; Matsumura, Y.; Otsuki, S.; Kusano, J.; Yamamoto, M.; Nakamura, N.; Tanabe, E.; Koyama, K.; Yoshida, M.; Fujimori, R.; Yasui, A.

    2015-06-01

    We are developing compact electron linear accelerators (hereafter linac) with high RF (Radio Frequency) frequency (9.3 GHz, wavelength 32.3 mm) of X-band and applying to medicine and non-destructive testing. Especially, potable 950 keV and 3.95 MeV linac X-ray sources have been developed for on-site transmission testing at several industrial plants and civil infrastructures including bridges. 6 MeV linac have been made for pinpoint X-ray dynamic tracking cancer therapy. The length of the accelerating tube is ∼600 mm. The electron beam size at the X-ray target is less than 1 mm and X-ray spot size at the cancer is less than 3 mm. Several hardware and software are under construction for dynamic tracking therapy for moving lung cancer. Moreover, as an ultimate compact linac, we are designing and manufacturing a laser dielectric linac of ∼1 MeV with Yr fiber laser (283 THz, wavelength 1.06 pm). Since the wavelength is 1.06 μm, the length of one accelerating strcture is tens pm and the electron beam size is in sub-micro meter. Since the sizes of cell and nuclear are about 10 and 1 μm, respectively, we plan to use this “On-chip” linac for radiation-induced DNA damage/repair analysis. We are thinking a system where DNA in a nucleus of cell is hit by ∼1 μm electron or X-ray beam and observe its repair by proteins and enzymes in live cells in-situ.

  15. Phenotyping of Leukocytes and Leukocyte-Derived Extracellular Vesicles

    PubMed Central

    Pugholm, Lotte Hatting; Bæk, Rikke; Søndergaard, Evo Kristina Lindersson; Revenfeld, Anne Louise Schacht; Jørgensen, Malene Møller; Varming, Kim

    2016-01-01

    Extracellular vesicles (EVs) have a demonstrated involvement in modulating the immune system. It has been proposed that EVs could be used as biomarkers for detection of inflammatory and immunological disorders. Consequently, it is of great interest to investigate EVs in more detail with focus on immunological markers. In this study, five major leukocyte subpopulations and the corresponding leukocyte-derived EVs were phenotyped with focus on selected immunological lineage-specific markers and selected vesicle-related markers. The leukocyte-derived EVs displayed phenotypic differences in the 34 markers investigated. The majority of the lineage-specific markers used for identification of the parent cell types could not be detected on EVs released from monocultures of the associated cell types. In contrast, the vesicular presentation of CD9, CD63, and CD81 correlated to the cell surface expression of these markers, however, with few exceptions. Furthermore, the cellular expression of CD9, CD63, and CD81 varied between leukocytes present in whole blood and cultured leukocytes. In summary, these data demonstrate that the cellular and vesicular presentation of selected lineage-specific and vesicle-related markers may differ, supporting the accumulating observations that sorting of molecular cargo into EVs is tightly controlled. PMID:27195303

  16. SU-E-J-156: Preclinical Inverstigation of Dynamic Tumor Tracking Using Vero SBRT Linear Accelerator: Motion Phantom Dosimetry Study

    SciTech Connect

    Mamalui-Hunter, M; Wu, J; Li, Z; Su, Z

    2014-06-01

    Purpose: Following the ‘end-to-end testing’ paradigm of Dynamic Target Tracking option in our Image-Guided dedicated SBRT VeroTM linac, we verify the capability of the system to deliver planned dose to moving targets in the heterogeneous thorax phantom (CIRSTM). The system includes gimbaled C-band linac head, robotic 6 degree of freedom couch and a tumor tracking method based on predictive modeling of target position using fluoroscopically tracked implanted markers and optically tracked infrared reflecting external markers. Methods: 4DCT scan of the motion phantom with the VisicoilTM implanted marker in the close vicinity of the target was acquired, the ‘exhale’=most prevalent phase was used for planning (iPlan by BrainLabTM). Typical 3D conformal SBRT treatment plans aimed to deliver 6-8Gy/fx to two types of targets: a)solid water-equivalent target 3cm in diameter; b)single VisicoilTM marker inserted within lung equivalent material. The planning GTV/CTV-to-PTV margins were 2mm, the block margins were 3 mm. The dose calculated by MonteCarlo algorithm with 1% variance using option Dose-to-water was compared to the ion chamber (CC01 by IBA Dosimetry) measurements in case (a) and GafchromicTM EBT3 film measurements in case (b). During delivery, the target 6 motion patterns available as a standard on CIRSTM motion phantom were investigated: in case (a), the target was moving along the designated sine or cosine4 3D trajectory; in case (b), the inserted marker was moving sinusoidally in 1D. Results: The ion chamber measurements have shown the agreement with the planned dose within 1% under all the studied motion conditions. The film measurements show 98.1% agreement with the planar calculated dose (gamma criteria: 3%/3mm). Conclusion: We successfully verified the capability of the SBRT VeroTM linac to perform real-time tumor tracking and accurate dose delivery to the target, based on predictive modeling of the correlation between implanted marker motion and

  17. Is Chronic Asthma Associated with Shorter Leukocyte Telomere Length at Midlife?

    PubMed Central

    Shalev, Idan; Sears, Malcolm R.; Hancox, Robert J.; Lee Harrington, Hona; Houts, Renate; Moffitt, Terrie E.; Sugden, Karen; Williams, Benjamin; Poulton, Richie; Caspi, Avshalom

    2014-01-01

    Rationale: Asthma is prospectively associated with age-related chronic diseases and mortality, suggesting the hypothesis that asthma may relate to a general, multisystem phenotype of accelerated aging. Objectives: To test whether chronic asthma is associated with a proposed biomarker of accelerated aging, leukocyte telomere length. Methods: Asthma was ascertained prospectively in the Dunedin Multidisciplinary Health and Development Study cohort (n = 1,037) at nine in-person assessments spanning ages 9–38 years. Leukocyte telomere length was measured at ages 26 and 38 years. Asthma was classified as life-course-persistent, childhood-onset not meeting criteria for persistence, and adolescent/adult-onset. We tested associations between asthma and leukocyte telomere length using regression models. We tested for confounding of asthma-leukocyte telomere length associations using covariate adjustment. We tested serum C-reactive protein and white blood cell counts as potential mediators of asthma-leukocyte telomere length associations. Measurements and Main Results: Study members with life-course-persistent asthma had shorter leukocyte telomere length as compared with sex- and age-matched peers with no reported asthma. In contrast, leukocyte telomere length in study members with childhood-onset and adolescent/adult-onset asthma was not different from leukocyte telomere length in peers with no reported asthma. Adjustment for life histories of obesity and smoking did not change results. Study members with life-course-persistent asthma had elevated blood eosinophil counts. Blood eosinophil count mediated 29% of the life-course-persistent asthma-leukocyte telomere length association. Conclusions: Life-course-persistent asthma is related to a proposed biomarker of accelerated aging, possibly via systemic eosinophilic inflammation. Life histories of asthma can inform studies of aging. PMID:24956257

  18. Elemental composition of leukocyte subfractions

    NASA Astrophysics Data System (ADS)

    Admans, L. L.; Spyrou, N. M.

    2003-01-01

    The aim of this preliminary investigation was to determine the elemental concentration of various subfractions of leukocytes in a normal subject. Little work has been published on the elemental composition of these subfractions. First, a reliable technique for separation of these subfractions had to be established so that it could be applied to the determination of elemental concentrations in leukocyte subfractions from patients undergoing heart bypass surgery. Instrumental neutron activation analysis (INAA) utilising short irradiation and counting was the technique employed. Various washing media were examined during the separation of the leukocyte subfractions, for contamination of these small samples of peripheral blood mononuclear cells (PBMC) and polymorphonuclearcytes (PMN). Early results showed Mg and Se were present in these subfractions. Possibilities for further work are also discussed.

  19. Radiation-induced normal tissue injury: role of adhesion molecules in leukocyte-endothelial cell interactions.

    PubMed

    Quarmby, S; Kumar, P; Kumar, S

    1999-07-30

    The late onset of necrosis and fibrosis in normal tissues can be a serious consequence of radiotherapy in cancer patients. Because radiation-induced vascular injury precedes the tissue damage, vascular injury is regarded as crucial in the pathogenesis of tissue damage. An understanding of the processes responsible is essential to develop strategies for the amelioration of radiation-induced normal tissue damage. Leukocyte infiltration is commonly observed at sites of irradiation and is likely to lead to the acceleration and/or induction of parenchymal atrophy, fibrosis and necrosis in normal tissues following radiotherapy. The molecular mechanisms mediating leukocyte infiltration of tissues during inflammation have been studied extensively. It is now well established that cell adhesion molecules (CAMs) expressed on leukocytes and endothelial cells control the trafficking of leukocytes from the blood vessel lumen in these conditions. CAMs including E (endothelial), P (platelet) and L (leukocyte)-selectins, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), beta1 and beta2 integrins and CD31 are involved in the cascade of events resulting in rolling, arrest and transmigration of leukocytes through the inflamed endothelium. Whether a similar sequence of molecular events induces leukocyte sequestration in irradiated normal tissues is not known. This review is focussed on the role of CAMs in radiation-induced leukocyte infiltration of normal tissues and the therapeutic implications of these findings. PMID:10399956

  20. Selective Harvesting of Marginating-pulmonary Leukocytes.

    PubMed

    Shaashua, Lee; Sorski, Liat; Melamed, Rivka; Ben-Eliyahu, Shamgar

    2016-01-01

    Marginating-pulmonary (MP) leukocytes are leukocytes that adhere to the inner endothelium of the lung capillaries. MP-leukocytes were shown to exhibit unique composition and characteristics compared to leukocytes of other immune compartments. Evidence suggests higher cytotoxicity of natural killer cells, and a distinct pro- and anti-inflammatory profile of the MP-leukocyte population compared to circulating or splenic immunocytes. The method presented herein enables selective harvesting of MP-leukocytes by forced perfusion of the lungs in either mice or rats. In contrast to other methods used to extract lung-leukocytes, such as tissue grinding and biological degradation, this method exclusively yields leukocytes from the lung capillaries, uncontaminated with parenchymal, interstitial, and broncho-alveolar cells. In addition, the perfusion technique better preserves the integrity and the physiological milieu of MP-leukocytes, without inducing physiological responses due to tissue processing. This unique MP leukocyte population is strategically located to identify and react towards abnormal circulating cells, as all circulating malignant cells and infected cells are detained while passing through the lung capillaries, physically interacting with endothelial cells and resident leukocytes,. Thus, selective harvesting of MP-leukocytes and their study under various conditions may advance our understanding of their biological and clinical significance, specifically with respect to controlling circulating aberrant cells and lung-related diseases. PMID:27023665

  1. Leukocyte margination at arteriole shear rate

    PubMed Central

    Takeishi, Naoki; Imai, Yohsuke; Nakaaki, Keita; Yamaguchi, Takami; Ishikawa, Takuji

    2014-01-01

    Abstract We numerically investigated margination of leukocytes at arteriole shear rate in straight circular channels with diameters ranging from 10 to 22 μm. Our results demonstrated that passing motion of RBCs effectively induces leukocyte margination not only in small channels but also in large channels. A longer time is needed for margination to occur in a larger channel, but once a leukocyte has marginated, passing motion of RBCs occurs continuously independent of the channel diameter, and leukocyte margination is sustained for a long duration. We also show that leukocytes rarely approach the wall surface to within a microvillus length at arteriole shear rate. PMID:24907300

  2. A Model of Canine Leukocyte Telomere Dynamics

    PubMed Central

    Benetos, Athanase; Kimura, Masayuki; Labat, Carlos; Buchoff, Gerald M.; Huber, Shell; Labat, Laura; Lu, Xiaobin; Aviv, Abraham

    2011-01-01

    Summary Recent studies have found associations of leukocyte telomere length (TL) with diseases of aging and with longevity. However, it is unknown whether birth leukocyte TL or its age-dependent attrition— the two factors that determine leukocyte TL dynamics— explains these associations, since acquiring this information entails monitoring individuals over their entire life course. We tested in dogs a model of leukocyte TL dynamics, based on the following premises: (i) TL is synchronized among somatic tissues; (ii) TL in skeletal muscle, which is largely post-mitotic, is a measure of TL in early development; (iii) the difference between TL in leukocytes and muscle (ΔLMTL) is the extent of leukocyte TL shortening since early development. Using this model, we observed in 83 dogs (ages 4–42 months) no significant change with age in TLs of skeletal muscle and a shorter TL in leukocytes than in skeletal muscle (P<0.0001). Age explained 43% of the variation in ΔLMTL (P<0.00001) but only 6% of the variation in leukocyte TL (P=0.035) among dogs. Accordingly, muscle TL and ΔLMTL provide the two essential factors of leukocyte TL dynamics in the individual dog. When applied to humans, the partition of the contribution of leukocyte TL during early development versus telomere shortening afterward might provide information about whether the individual’s longevity is calibrated to either one or both factors that define leukocyte TL dynamics. PMID:21917112

  3. Leukocytes recruited by tumor-derived HMGB1 sustain peritoneal carcinomatosis.

    PubMed

    Cottone, Lucia; Capobianco, Annalisa; Gualteroni, Chiara; Monno, Antonella; Raccagni, Isabella; Valtorta, Silvia; Canu, Tamara; Tomaso, Tiziano Di; Lombardo, Angelo; Esposito, Antonio; Moresco, Rosa Maria; Maschio, Alessandro Del; Naldini, Luigi; Rovere-Querini, Patrizia; Bianchi, Marco E; Manfredi, Angelo A

    2016-05-01

    The factors that determine whether disseminated transformed cells in vivo yield neoplastic lesions have only been partially identified. We established an ad hoc model of peritoneal carcinomatosis by injecting colon carcinoma cells in mice. Tumor cells recruit inflammatory leukocytes, mostly macrophages, and generate neoplastic peritoneal lesions. Phagocyte depletion via clodronate treatment reduces neoplastic growth. Colon carcinoma cells release a prototypic damage-associated molecular pattern (DAMP)/alarmin, High Mobility Group Box1 (HMGB1), which attracts leukocytes. Exogenous HMGB1 accelerates leukocyte recruitment, macrophage infiltration, tumor growth and vascularization. Lentiviral-based HMGB1 knockdown or pharmacological interference with its extracellular impair macrophage recruitment and tumor growth. Our findings provide a preclinical proof of principle that strategies based on preventing HMGB1-driven recruitment of leukocytes could be used for treating peritoneal carcinomatosis. PMID:27467932

  4. Focal MMP-2 and MMP-9 activity at the blood-brain barrier promotes chemokine-induced leukocyte migration.

    PubMed

    Song, Jian; Wu, Chuan; Korpos, Eva; Zhang, Xueli; Agrawal, Smriti M; Wang, Ying; Faber, Cornelius; Schäfers, Michael; Körner, Heinrich; Opdenakker, Ghislain; Hallmann, Rupert; Sorokin, Lydia

    2015-02-24

    Although chemokines are sufficient for chemotaxis of various cells, increasing evidence exists for their fine-tuning by selective proteolytic processing. Using a model of immune cell chemotaxis into the CNS (experimental autoimmune encephalomyelitis [EAE]) that permits precise localization of immigrating leukocytes at the blood-brain barrier, we show that, whereas chemokines are required for leukocyte migration into the CNS, additional MMP-2/9 activities specifically at the border of the CNS parenchyma strongly enhance this transmigration process. Cytokines derived from infiltrating leukocytes regulate MMP-2/9 activity at the parenchymal border, which in turn promotes astrocyte secretion of chemokines and differentially modulates the activity of different chemokines at the CNS border, thereby promoting leukocyte migration out of the cuff. Hence, cytokines, chemokines, and cytokine-induced MMP-2/9 activity specifically at the inflammatory border collectively act to accelerate leukocyte chemotaxis across the parenchymal border. PMID:25704809

  5. Glycobiology of leukocyte trafficking in inflammation.

    PubMed

    Wright, Rachael D; Cooper, Dianne

    2014-12-01

    To fulfill their potential, leukocytes must be able to exit the vasculature and reach the site of inflammation within the tissue. This process of leukocyte extravasation is a tightly regulated sequence of events that is governed by a host of cell adhesion molecules, cytokines, chemokines and lipid mediators. Of major importance to this process and the function of many of the proteins and lipids involved is the posttranslational modification of these moieties by glycosylation. The glycosylation process is coordinated by multiple enzymes that add and remove saccharides to/from glycan structures on proteins and lipids, resulting in a unique molecular signature that affords specificity to the molecules involved in leukocyte recruitment. This review will discuss how glycosylation impacts the function of these key molecules involved in the recruitment of leukocytes during inflammation and the function of specific lectins (carbohydrate-binding proteins) that have a role in leukocyte trafficking. PMID:25258391

  6. Disseminated Intravascular Coagulation Induced with Leukocyte Procoagulant

    PubMed Central

    Kociba, Gary J.; Griesemer, Richard A.

    1972-01-01

    The procoagulant activity of rabbit peritoneal leukocytes significantly increased when the leukocytes were incubated in suspension cultures at 37 C for 24 hours. Intravenous infusions of Iysates of 232 × 106 rabbit leukocytes which had been incubated in cultures at 37 C for 24 hours produced disseminated intravascular coagulation and vasculitis involving the pulmonary arteries in normal rabbits. Intraaortic infusions of lysates of 230 × 106 similarly incubated leukocytes produced renal thrombosis and renal cortical necrosis in normal rabbits. These observations suggest that the procoagulant of granulocytic leukocytes could play a role in the generalized Shwartzman reaction and other syndromes of disseminated intravascular coagulation. ImagesFig 3Fig 4Fig 5Fig 6Fig 7Fig 1Fig 2 PMID:5086898

  7. Leukocyte rheology in recent stroke.

    PubMed

    Ernst, E; Matrai, A; Paulsen, F

    1987-01-01

    Eighteen patients with recent ischemic stroke were compared with an equal number of matched controls. Standardized suspensions of red cells as well as of red and white cells were filtered in a new filtration apparatus capable of discriminating between cell deformability and filter occlusion. Results show that red cell deformability, although slightly lower than in controls, is not significantly altered in stroke patients. Filter occlusion, however, was significantly higher in patients when red and white cell suspensions were filtered, but not when red cell suspensions were used, suggesting that white cell filterability is impaired after stroke, which could be due to decreased deformability and/or increased adhesiveness of leukocytes. Slowed white cell passage may also occur in the living microcirculation and may present an obstacle to nutritive flow in exchange vessels, possibly contributing to local ischemia and tissue necrosis after stroke. PMID:3810770

  8. Tracking the dynamic seroma cavity using fiducial markers in patients treated with accelerated partial breast irradiation using 3D conformal radiotherapy

    SciTech Connect

    Yue, Ning J.; Haffty, Bruce G.; Goyal, Sharad

    2013-02-15

    Purpose: The purpose of the present study was to perform an analysis of the changes in the dynamic seroma cavity based on fiducial markers in early stage breast cancer patients treated with accelerated partial breast irradiation (APBI) using three-dimensional conformal external beam radiotherapy (3D-CRT). Methods: A prospective, single arm trial was designed to investigate the utility of gold fiducial markers in image guided APBI using 3D-CRT. At the time of lumpectomy, four to six suture-type gold fiducial markers were sutured to the walls of the cavity. Patients were treated with a fractionation scheme consisting of 15 fractions with a fractional dose of 333 cGy. Treatment design and planning followed NSABP/RTOG B-39 guidelines. During radiation treatment, daily kV imaging was performed and the markers were localized and tracked. The change in distance between fiducial markers was analyzed based on the planning CT and daily kV images. Results: Thirty-four patients were simulated at an average of 28 days after surgery, and started the treatment on an average of 39 days after surgery. The average intermarker distance (AiMD) between fiducial markers was strongly correlated to seroma volume. The average reduction in AiMD was 19.1% (range 0.0%-41.4%) and 10.8% (range 0.0%-35.6%) for all the patients between simulation and completion of radiotherapy, and between simulation and beginning of radiotherapy, respectively. The change of AiMD fits an exponential function with a half-life of seroma shrinkage. The average half-life for seroma shrinkage was 15 days. After accounting for the reduction which started to occur after surgery through CT simulation and treatment, radiation was found to have minimal impact on the distance change over the treatment course. Conclusions: Using the marker distance change as a surrogate for seroma volume, it appears that the seroma cavity experiences an exponential reduction in size. The change in seroma size has implications in the size of

  9. [Investigation on bovine leukocyte adhesion deficiency].

    PubMed

    Ma, Jin-Zhu; Cui, Yu-Dong; Zhu, Zhan-Bo; Cao, Hong-Wei; Piao, Fan-Ze

    2006-10-01

    Bovine leukocyte adhesion deficiency (BLAD) is autosomal recessive disease. The pathogeny of BLAD is genic mutation of CD18-integrins on the leukocyte. In order to know the carrier and occurrence of bovine leukocyte adhesion deficiency (BLAD) among cows age from one to six years old in China, 1,000 cows were investigated by means of amplifying a CD18 gene fragment via reverse transcriptase-PCR followed by restriction digestion with Taq I. Results showed that 19 cows were BLAD carriers, indicating that the BLAD carrier rate was 1.9 percent. In addition, one cow was found to have BLAD. PMID:17035180

  10. Leukocyte Activation in Obese Patients

    PubMed Central

    Minervino, Daniele; Gumiero, Daniela; Nicolazzi, Maria Anna; Carnicelli, Annamaria; Fuorlo, Mariella; Guidone, Caterina; Di Gennaro, Leonardo; Fattorossi, Andrea; Mingrone, Geltrude; Landolfi, Raffaele

    2015-01-01

    Abstract The rising prevalence of obesity is a major global health problem. In severe obesity, bariatric surgery (BS) allows to obtain a significant weight loss and comorbidities improvement, among them one of the factors is the thrombotic risk. In this observational study, we measured indices of leukocyte activation in severely obese patients as markers of increased thrombotic risk in relation with serum markers of inflammation before and after BS. Frequency of polymorphonuclear neutrophil-platelet (PLT) and monocyte (MONO)-PLT aggregates as well as of tissue factor (TF) expressing MONOs was measured in the peripheral blood of 58 consecutive obese patients and 30 healthy controls. In 31 of the 58 obese patients, data obtained at the enrollment were compared with those obtained at 3, 6, and 12 months after BS. Compared with healthy controls, obese patients showed a higher frequency of polymorphonuclear leukocyte (PMNL)-PLT aggregates (7.47 ± 2.45 [6.82–8.11]% vs 5.85 ± 1.89 [5.14–6.55]%, P = 0.001), MONO-PLT aggregates (12.31 ± 7.33 [10.38–14.24]% vs 8.14 ± 2.22 [7.31–8.97]%, P < 0.001), and TF expressing MONOs (4.01 ± 2.11 [3.45–4.56]% vs 2.64 ± 1.65 [2.02–3.25]%, P = 0.002). PMNL-PLT and MONO-PLT aggregate frequency was positively correlated with TF expressing MONOs (R2 = 0.260, P = 0.049 and R2 = 0.318, P = 0.015, respectively). BS was performed in 31 patients and induced a significant reduction of the body mass index, and waist and hip circumferences. These effects were associated with a significant decrease of PMNL-PLT aggregates at 12 months (7.58 ± 2.27 [6.75–8.42]% vs 4.47 ± 1.11 [3.93–5.01]%, P < 0.001), and a reduction of TF expressing MONOs at 6 (3.82 ± 2.04 [3.07–4.57]% vs 1.60 ± 1.69 [0.30–2.90]%, P = 0.008) and 12 months (3.82 ± 2.04 [3.07–4.57]% vs 1.71 ± 0.54 [1.45–1.97]%, P = 0.001) after BS. These data suggest that leukocyte

  11. TrackEye tracking algorithm characterization

    NASA Astrophysics Data System (ADS)

    Valley, Michael T.; Shields, Robert W.; Reed, Jack M.

    2004-10-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  12. TrackEye tracking algorithm characterization.

    SciTech Connect

    Reed, Jack W.; Shields, Rob W; Valley, Michael T.

    2004-08-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  13. 21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Leukocyte alkaline phosphatase test. 864.7660... Leukocyte alkaline phosphatase test. (a) Identification. A leukocyte alkaline phosphatase test is a device used to identify the enzyme leukocyte alkaline phosphatase in neutrophilic granulocytes...

  14. 21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Leukocyte alkaline phosphatase test. 864.7660... Leukocyte alkaline phosphatase test. (a) Identification. A leukocyte alkaline phosphatase test is a device used to identify the enzyme leukocyte alkaline phosphatase in neutrophilic granulocytes...

  15. Indium-111 autologous leukocyte imaging in pancreatitis

    SciTech Connect

    Anderson, J.R.; Spence, R.A.; Laird, J.D.; Ferguson, W.R.; Kennedy, T.L.

    1986-03-01

    Thirty-nine patients with acute pancreatitis have been assessed using a prognostic factor grading system, abdominal ultrasound, and autologous leukocyte imaging. Both prognostic factor grading and leukocyte imaging can accurately assess the severity of the disease early in its course. All patients with a negative indium-labeled leukocyte image recovered without sequelae, whereas five of the 12 patients with a positive image developed complications, including two deaths. Abdominal ultrasound is of no value in assessing severity, but is a useful method of detecting those patients with gallstone-associated disease. In patients with suspected abscess formation following acute pancreatitis, indium leukocyte imaging does not differentiate between fat necrosis and abscess formation. In this situation, computerized tomography should be carried out before laparotomy is undertaken.

  16. Transient reductions in leukocyte/endothelium interaction occur early in hyperoxic lung injury, as seen using scanning electron microscopy (SEM)

    SciTech Connect

    Allen, C.B.; Tucker, A. Colorado State Univ., Ft. Collins )

    1990-02-26

    Exposure of rats to 100% O{sub 2} results in an increased number of neutrophils seen adjacent to pulmonary capillary endothelium. Preliminary studies suggested that serotonin depletion using parachlorophenyalanine (PCPA) accelerated the progression of hyperoxic lung injury. The authors chose to study leukocyte margination in hyperoxic lung injury using SEM to survey pulmonary vessels >20 um diameter in serotonin-intact rats and serotonin-depleted rats exposed to 100% O{sub 2} for 12, 24, 36, 48, 56, and 60 hours. In control rats, the average density of marginated leukocytes was 1,703/mm{sup 2}. At 12, 24 and 36 hours of exposure to 100% O{sub 2}, this density had been reduced to 599/mm{sup 2}, 683/mm{sup 2} and 733/mm{sup 2}, respectively (p{le}0.05). At 48 hours, the leukocyte density, 2,009/mm{sup 2}, was greater than the control value. At 60 hours of exposure, leukocyte densities were not different from control values. Serotonin-depletion did not significantly change this pattern. These findings suggest that hyperoxia causes an earlier change in endothelium/leukocyte interaction than previously thought, and that after early reductions in leukocyte margination, leukocyte densities rebound toward control levels by 48 hours of exposure.

  17. Leukocyte filtration in lung transplantation.

    PubMed

    Kurusz, Mark; Roach, John D; Vertrees, Roger A; Girouard, Mark K; Lick, Scott D

    2002-05-01

    Controlled reperfusion of the transplanted lung has been used in nine consecutive patients to decrease manifestations of lung reperfusion injury. An extracorporeal circuit containing a roller pump, heat exchanger and leukodepleting filter is primed with substrate-enhanced reperfusion solution mixed with approximately 2000 ml of the patient's blood. This solution is slowly recirculated to remove leukocytes prior to reperfusion. When the pulmonary anastomoses are completed, the pulmonary artery is cannulated through the untied anastomosis using a catheter containing a pressure lumen for measurement of infusion pressure. An atrial clamp is left in place on the patient's native atrial cuff to decrease the risk of systemic air embolism during the brief period of reperfusion from the extracorporeal reservoir. During reperfusion, the water bath to the heat exchanger is kept at 35 degrees C and the flow rate for reperfusion solution is between 150 and 200 m/min, keeping the pulmonary artery pressure <14 mmHg. Eight of nine patients were ventilated on 40% inspired oxygen within a few hours of operation and 7/9 were extubated on or before postoperative day 1. Six of nine patients are long-term survivors. PMID:12009087

  18. The multiple faces of leukocyte interstitial migration

    PubMed Central

    Lämmermann, Tim; Germain, Ronald N.

    2014-01-01

    Spatiotemporal control of leukocyte dynamics within tissues is critical for successful innate and adaptive immune responses. Homeostatic trafficking and coordinated infiltration into and within sites of inflammation and infection rely on signaling in response to extracellular cues that in turn controls a variety of intracellular protein networks regulating leukocyte motility, migration, chemotaxis, positioning, and cell–cell interaction. In contrast to mesenchymal cells, leukocytes migrate in an amoeboid fashion by rapid cycles of actin polymerization and actomyosin contraction, and their migration in tissues is generally referred to as low adhesive and nonproteolytic. The interplay of actin network expansion, contraction, and adhesion shapes the exact mode of amoeboid migration, and in this review, we explore how leukocyte subsets potentially harness the same basic biomechanical mechanisms in a cell-type-specific manner. Most of our detailed understanding of these processes derives from in vitro migration studies in three-dimensional gels and confined spaces that mimic geometrical aspects of physiological tissues. We summarize these in vitro results and then critically compare them to data from intravital imaging of leukocyte interstitial migration in mouse tissues. We outline the technical challenges of obtaining conclusive mechanistic results from intravital studies, discuss leukocyte migration strategies in vivo, and present examples of mode switching during physiological interstitial migration. These findings are also placed in the context of leukocyte migration defects in primary immunodeficiencies. This overview of both in vitro and in vivo studies highlights recent progress in understanding the molecular and biophysical mechanisms that shape robust leukocyte migration responses in physiologically complex and heterogeneous environments. PMID:24573488

  19. Extrapolating target tracks

    NASA Astrophysics Data System (ADS)

    Van Zandt, James R.

    2012-05-01

    Steady-state performance of a tracking filter is traditionally evaluated immediately after a track update. However, there is commonly a further delay (e.g., processing and communications latency) before the tracks can actually be used. We analyze the accuracy of extrapolated target tracks for four tracking filters: Kalman filter with the Singer maneuver model and worst-case correlation time, with piecewise constant white acceleration, and with continuous white acceleration, and the reduced state filter proposed by Mookerjee and Reifler.1, 2 Performance evaluation of a tracking filter is significantly simplified by appropriate normalization. For the Kalman filter with the Singer maneuver model, the steady-state RMS error immediately after an update depends on only two dimensionless parameters.3 By assuming a worst case value of target acceleration correlation time, we reduce this to a single parameter without significantly changing the filter performance (within a few percent for air tracking).4 With this simplification, we find for all four filters that the RMS errors for the extrapolated state are functions of only two dimensionless parameters. We provide simple analytic approximations in each case.

  20. Leukocyte chemoattractant activity of diacylglycerol

    SciTech Connect

    Wright, T.M.; Hoffman, R.D.; Nishijima, J.; Shin, H.S.

    1986-03-05

    Phosphatidylinositol breakdown with the generation of 1,2-diacylglycerol (1,2-DG) and inositol phosphates occurs in response to receptor mediated stimulation of lymphocytes and polymorphonuclear neutrophils (PMN). In the authors attempt to demonstrate the direct role of 1,2-DG in cell migration, they have found 1,2 dioctanoyl glycerol (1,2-C8DG) to be a chemoattractant for 6C3HED, a mouse thymic lymphoma, and human peripheral blood PMN's. The chemoattractant activity for both cell types was observed at concentrations from 0.5 to 10mM in an under agarose assay. The maximum effect of 1,2-C8DG on 6C3HED cells was similar to that of 1mM lysophosphatidylcholine and the maximum effect of 1,2-C8DG on PMN's was similar to that of 10/sup -7/M f-met-leu-phe. Other 1,2-DG's with acyl chains ranging from 6 to 18 carbons in length and 1-oleoyl-2-acetyl-glycerol were also chemoattractants for 6C3HED, although their activities were less than 1,2-C8DG. In addition, phorbol myristate acetate (PMA), another activator of protein kinase C, was a chemoattractant for 6C3HED and human PMN's. PMA was more potent than 1,2-C8DG for both 6C3HED and PMN's with chemoattractant activity in the range of 30nM to 1..mu..M. These studies support the direct role of 1,2-DG in the transduction of chemotactic stimuli in leukocytes and further suggest that the formation of diacylglycerol represents a common step in the migratory responses of lymphoid and myeloid cells.

  1. Leukocyte Telomere Length in Major Depression: Correlations with Chronicity, Inflammation and Oxidative Stress - Preliminary Findings

    PubMed Central

    Wolkowitz, Owen M.; Mellon, Synthia H.; Epel, Elissa S.; Lin, Jue; Dhabhar, Firdaus S.; Su, Yali; Reus, Victor I.; Rosser, Rebecca; Burke, Heather M.; Kupferman, Eve; Compagnone, Mariana; Nelson, J. Craig; Blackburn, Elizabeth H.

    2011-01-01

    Background Depression is associated with an unusually high rate of aging-related illnesses and early mortality. One aspect of “accelerated aging” in depression may be shortened leukocyte telomeres. When telomeres critically shorten, as often occurs with repeated mitoses or in response to oxidation and inflammation, cells may die. Indeed, leukocyte telomere shortening predicts early mortality and medical illnesses in non-depressed populations. We sought to determine if leukocyte telomeres are shortened in Major Depressive Disorder (MDD), whether this is a function of lifetime depression exposure and whether this is related to putative mediators, oxidation and inflammation. Methodology Leukocyte telomere length was compared between 18 unmedicated MDD subjects and 17 controls and was correlated with lifetime depression chronicity and peripheral markers of oxidation (F2-isoprostane/Vitamin C ratio) and inflammation (IL-6). Analyses were controlled for age and sex. Principal Findings The depressed group, as a whole, did not differ from the controls in telomere length. However, telomere length was significantly inversely correlated with lifetime depression exposure, even after controlling for age (p<0.05). Average telomere length in the depressed subjects who were above the median of lifetime depression exposure (≥9.2 years' cumulative duration) was 281 base pairs shorter than that in controls (p<0.05), corresponding to approximately seven years of “accelerated cell aging.” Telomere length was inversely correlated with oxidative stress in the depressed subjects (p<0.01) and in the controls (p<0.05) and with inflammation in the depressed subjects (p<0.05). Conclusions These preliminary data indicate that accelerated aging at the level of leukocyte telomeres is proportional to lifetime exposure to MDD. This might be related to cumulative exposure to oxidative stress and inflammation in MDD. This suggest that telomere shortening does not antedate depression and is

  2. Leukocyte Recruitment and Ischemic Brain Injury

    PubMed Central

    Yilmaz, Gokhan

    2010-01-01

    Leukocytes are recruited into the cerebral microcirculation following an ischemic insult. The leukocyte–endothelial cell adhesion manifested within a few hours after ischemia (followed by reperfusion, I/R) largely reflects an infiltration of neutrophils, while other leukocyte populations appear to dominate the adhesive interactions with the vessel wall at 24 h of reperfusion. The influx of rolling and adherent leukocytes is accompanied by the recruitment of adherent platelets, which likely enhances the cytotoxic potential of the leukocytes to which they are attached. The recruitment of leukocytes and platelets in the postischemic brain is mediated by specific adhesion glycoproteins expressed by the activated blood cells and on cerebral microvascular endothelial cells. This process is also modulated by different signaling pathways (e.g., CD40/CD40L, Notch) and cytokines (e.g., RANTES) that are activated/released following I/R. Some of the known risk factors for cardiovascular disease, including hypercholesterolemia and obesity appear to exacerbate the leukocyte and platelet recruitment elicited by brain I/R. Although lymphocyte–endothelial cell and –platelet interactions in the postischemic cerebral microcirculation have not been evaluated to date, recent evidence in experimental animals implicate both CD4+ and CD8+ T-lymphocytes in the cerebral microvascular dysfunction, inflammation, and tissue injury associated with brain I/R. Evidence implicating regulatory T-cells as cerebroprotective modulators of the inflammatory and tissue injury responses to brain I/R support a continued focus on leukocytes as a target for therapeutic intervention in ischemic stroke. PMID:19579016

  3. Image based cardiac acceleration map using statistical shape and 3D+t myocardial tracking models; in-vitro study on heart phantom

    NASA Astrophysics Data System (ADS)

    Pashaei, Ali; Piella, Gemma; Planes, Xavier; Duchateau, Nicolas; de Caralt, Teresa M.; Sitges, Marta; Frangi, Alejandro F.

    2013-03-01

    It has been demonstrated that the acceleration signal has potential to monitor heart function and adaptively optimize Cardiac Resynchronization Therapy (CRT) systems. In this paper, we propose a non-invasive method for computing myocardial acceleration from 3D echocardiographic sequences. Displacement of the myocardium was estimated using a two-step approach: (1) 3D automatic segmentation of the myocardium at end-diastole using 3D Active Shape Models (ASM); (2) propagation of this segmentation along the sequence using non-rigid 3D+t image registration (temporal di eomorphic free-form-deformation, TDFFD). Acceleration was obtained locally at each point of the myocardium from local displacement. The framework has been tested on images from a realistic physical heart phantom (DHP-01, Shelley Medical Imaging Technologies, London, ON, CA) in which the displacement of some control regions was known. Good correlation has been demonstrated between the estimated displacement function from the algorithms and the phantom setup. Due to the limited temporal resolution, the acceleration signals are sparse and highly noisy. The study suggests a non-invasive technique to measure the cardiac acceleration that may be used to improve the monitoring of cardiac mechanics and optimization of CRT.

  4. Host-pathogen interactions: leukocyte phagocytosis and associated sequelae.

    PubMed

    Voyich, Jovanka M; DeLeo, Frank R

    2002-01-01

    Polymorphonuclear leukocytes (PMNs) are a critical component of the human innate immune response and are the first line of defense against invading microorganisms. Phagocytosis of invading microbes induces production of reactive oxygen species (ROS) by PMNs, which facilitates bactericidal activity. In addition to eliminating microorganisms, phagocytosis also accelerates PMN apoptosis, a process critical for resolution of inflammation. Inasmuch as leukocyte phagocytosis and ROS production are key components of the innate immune response, we developed flow cytometric methods to evaluate these processes in human PMNs. In contrast to traditional microscopy-based analyses, the methods described herein provide objective and high throughput measures of host cell-pathogen interactions. Importantly, they can be adapted for use with a number of fluorometric probes, and bacterium and host cell of choice, and each is based upon a common phagocytosis assay system. We also describe methods to measure phagocytosis-induced PMN apoptosis with this assay system. These methods entail detecting surface-exposed phosphatidylserine (early apoptosis), and measuring PMN chromatin condensation and DNA fragmentation (late apoptosis). Taken together, these assays provide rapid and accurate assessment of critical PMN processes. PMID:12815296

  5. Halloysite Nanotube Coatings Suppress Leukocyte Spreading.

    PubMed

    Hughes, Andrew D; Marsh, Graham; Waugh, Richard E; Foster, David G; King, Michael R

    2015-12-22

    The nanoscale topography of adhesive surfaces is known to be an important factor governing cellular behavior. Previous work has shown that surface coatings composed of halloysite nanotubes enhance the adhesion, and therefore capture of, rare target cells such as circulating tumor cells. Here we demonstrate a unique feature of these coatings in their ability to reduce the adhesion of leukocytes and prevent leukocyte spreading. Surfaces were prepared with coatings of halloysite nanotubes and functionalized for leukocyte adhesion with E-selectin, and the dilution of nanotube concentration revealed a threshold concentration below which cell spreading became comparable to smooth surfaces. Evaluation of surface roughness characteristics determined that the average distance between discrete surface features correlated with adhesion metrics, with a separation distance of ∼2 μm identified as the critical threshold. Computational modeling of the interaction of leukocytes with halloysite nanotube-coated surfaces of varying concentrations demonstrates that the geometry of the cell surface and adhesive counter-surface produces a significantly diminished effective contact area compared to a leukocyte interacting with a smooth surface. PMID:26605493

  6. Osteomyelitis: diagnosis with In-111-labeled leukocytes

    SciTech Connect

    Schauwecker, D.S.

    1989-04-01

    In a retrospective review, 485 patients with suspected osteomyelitis were studied. Of these, 453 patients were studied with both bone and indium-111 leukocyte scanning (173 sequentially and 280 simultaneously). The ability to determine that the infection was in bone rather than in adjacent soft tissue was greater with simultaneous bone scan and In-111 leukocyte studies than with sequential studies. The locations of suspected osteomyelitis were divided into central (containing active bone marrow), peripheral (hands and feet), and middle (between central and peripheral). Specificity remained high (about 90%) regardless of the location. Overall sensitivity was significantly lower in the central location than in the peripheral or middle location. Determination of whether the In-111 leukocyte activity was in bone or adjacent soft tissue was also more difficult when the infection was in the central location. For acute osteomyelitis, sensitivity was high regardless of the location. For chronic osteomyelitis, sensitivity was lower in the central location.

  7. Allograft rejection in cattle with bovine leukocyte adhesion deficiency.

    PubMed

    Müller, K E; Rutten, V P; Becker, C K; Hoek, A; Bernadina, W E; Wentink, G H; Figdor, C G

    1995-09-01

    In the present investigation cell-mediated immunity in animals with bovine leukocyte adhesion deficiency (BLAD) was studied by means of skin transplantation experiments. Autograft and allograft behaviour in animals with BLAD was compared with the behaviour of simultaneously transplanted autografts and allografts in healthy controls. Allograft survival time was prolonged in three BLAD cattle (28, 30, and 72 days) compared to six healthy controls (12-14 days). When transplantations were repeated on one animal with BLAD using skin grafts from the same donor, accelerated rejection was observed (allograft survival time decreased from 72 days at primary to 35 days at secondary and to 21 days at tertiary transplantation), suggesting the development of immunological memory. Graft-infiltrating lymphocytes that were obtained from allograft biopsies during the period of rejection, were shown to be from recipient origin (beta 2-integrin negative). Our findings demonstrate that, although prolonged allograft survival is observed in cattle with BLAD, skin allografts are ultimately rejected. PMID:8533316

  8. Leukocyte migration inhibition in nickel dermatitis.

    PubMed

    Mirza, A M; Perera, M G; Maccia, C A; Dziubynskyj, O G; Bernstein, I L

    1975-01-01

    Leukocyte migration inhibitory factor assay was employed as an in vitro diagnostic aid in nickel dermatitis, the second most common contact dermatitis in North America. 15 patch test-positive and 5 patch test-negative patients, all giving a past history suggestive of nickel dermatitis, were investigated. Significant inhibition of leukocyte migration in both groups of patients was obtained only with nickel sulfate-albumin conjugate and not with unconjugated nickel sulfate. Specificity of this system was tested by utilizing an unrelated metallic albumin complex, and no inhibition was found. When patch testing is equivocal or contraindicated, this in vitro technique may be a practical alternative. PMID:1102460

  9. The melanocortin system in leukocyte biology.

    PubMed

    Catania, Anna

    2007-02-01

    The melanocortin system is composed of the melanocortin peptides, adrenocorticotropic hormone and alpha-, beta-, and gamma-melanocyte-stimulating hormone, the melanocortin receptors (MCRs), and the endogenous antagonists agouti- and agouti-related protein. Melanocortin peptides exert multiple effects upon the host, including anti-inflammatory and immunomodulatory effects. Leukocytes are a source of melanocortins and a major target for these peptides. Because of reduced translocation of the nuclear factor NF-kappaB to the nucleus, MCR activation by their ligands causes a collective reduction of the most important molecules involved in the inflammatory process. This review examines how melanocortin peptides and their receptors participate in leukocyte biology. PMID:17041004

  10. Genetics Home Reference: leukocyte adhesion deficiency type 1

    MedlinePlus

    ... adhesion deficiency type 1 leukocyte adhesion deficiency type 1 Enable Javascript to view the expand/collapse boxes. ... All Close All Description Leukocyte adhesion deficiency type 1 is a disorder that causes the immune system ...

  11. Halo sign on indium-111 leukocyte scan in gangrenous cholecystitis

    SciTech Connect

    Bauman, J.M.; Boykin, M.; Hartshorne, M.F.; Cawthon, M.A.; Landry, A.J.

    1986-02-01

    A 56-year-old man with a long history of Crohn's disease was evaluated by In-111 labeled leukocyte scanning. A halo of leukocyte activity was seen around the gallbladder fossa. A gangrenous gallbladder was removed at surgery.

  12. Oxygen radical production by avian leukocytes.

    PubMed

    Conlon, P; Smith, D; Gowlett, T

    1991-04-01

    Oxygen radical production by heterophils of red-tailed hawks and chickens, and by neutrophils of calves, was evaluated in a chemiluminescence microassay. Leukocytes were isolated by centrifugation of blood in capillary tubes and then challenged with opsonized zymosan in the presence of luminol. Avian heterophils produced significantly fewer oxygen radicals than did bovine neutrophils. PMID:1884301

  13. MICROWAVES, HYPERTHERMIA, AND HUMAN LEUKOCYTE FUNCTION

    EPA Science Inventory

    The objective of this study is to determine whether exposure to microwaves (2450 MHz) affects the function of human leukocytes in the resting state and during antigenic or mitogenic challenge. This publication is a summary report of the construction and calibration of a waveguide...

  14. Changes in activities of enzymes related to energy metabolism in peripheral leukocytes of fattening steers.

    PubMed

    Kimura, N; Yoshimura, I; Sako, T; Inoue, A; Tadami, K; Arai, T

    2005-01-01

    Glucose, triglyceride, cholesterol and immunoreactive insulin (IRI) concentrations, some enzyme activities in plasma, and activities of enzymes related to energy metabolism in peripheral leukocytes were measured in fattening Japanese Black Wagyu x Holstein steers fed on different diets at 8, 12, 16, 20 and 24 months of age. The plasma IRI concentrations at 20 and 24 months of age were significantly higher than those at 8 months of age. Activities of hexokinase (HK), glucose-6-phosphate dehydrogenase (G6PD), aspartate aminotransferase (AST), and malate dehydrogenase (MDH) in cytosolic fractions, and glutamate dehydrogenase (GLDH), MDH and AST in mitochondrial fractions in peripheral leukocytes of steers at 24 months of age were significantly higher than those at 8 months. Increasing plasma insulin concentration was considered to induce acceleration of glucose utilization in leukocytes of fattening steers. The cytosolic ratio of MDH/lactate dehydrogenase (LDH) activity in leukocytes increased significantly in the fattening process and was considered to be a useful indicator for evaluating changes in energy metabolism in steers. PMID:15727288

  15. Bovine leukocyte adhesion deficiency: in vitro assessment of neutrophil function and leukocyte integrin expression.

    PubMed Central

    Olchowy, T W; Bochsler, P N; Neilsen, N R; Welborn, M G; Slauson, D O

    1994-01-01

    Bovine leukocyte adhesion deficiency (BLAD) was identified in a two-month-old Holstein heifer calf using DNA-polymerase chain reaction analysis of the affected calf and other clinical parameters. Neutrophil integrin expression (CD18, CD11a, CD11c), aggregation, and transendothelial migration were studied in vitro. Neutrophils were isolated from the affected calf and from normal, healthy, age-matched control Holstein calves. Neutrophils isolated from the affected BLAD calf had decreased expression of leukocyte integrins on their cell surface, decreased ability to aggregate in response to chemotactic stimuli, and decreased ability to migrate across bovine endothelial cell monolayers in vitro. Transendothelial migration of neutrophils from normal calves was reduced to levels comparable to the BLAD neutrophils by treatment with an anti-CD18 monoclonal antibody (MAb 60.3). Peripheral-blood lymphocytes from the BLAD calf also expressed negligible levels of leukocyte integrins, similar to their neutrophil counterparts. Our experimental findings in vitro correlate well with the clinical observations of decreased leukocyte trafficking and diminished host defense in leukocyte adhesion-deficient animals. The syndrome of BLAD may be a suitable model for one of the human leukocyte adhesion deficiency disorders. Images Fig. 4. PMID:7911733

  16. Bovine leukocyte adhesion deficiency: in vitro assessment of neutrophil function and leukocyte integrin expression.

    PubMed

    Olchowy, T W; Bochsler, P N; Neilsen, N R; Welborn, M G; Slauson, D O

    1994-04-01

    Bovine leukocyte adhesion deficiency (BLAD) was identified in a two-month-old Holstein heifer calf using DNA-polymerase chain reaction analysis of the affected calf and other clinical parameters. Neutrophil integrin expression (CD18, CD11a, CD11c), aggregation, and transendothelial migration were studied in vitro. Neutrophils were isolated from the affected calf and from normal, healthy, age-matched control Holstein calves. Neutrophils isolated from the affected BLAD calf had decreased expression of leukocyte integrins on their cell surface, decreased ability to aggregate in response to chemotactic stimuli, and decreased ability to migrate across bovine endothelial cell monolayers in vitro. Transendothelial migration of neutrophils from normal calves was reduced to levels comparable to the BLAD neutrophils by treatment with an anti-CD18 monoclonal antibody (MAb 60.3). Peripheral-blood lymphocytes from the BLAD calf also expressed negligible levels of leukocyte integrins, similar to their neutrophil counterparts. Our experimental findings in vitro correlate well with the clinical observations of decreased leukocyte trafficking and diminished host defense in leukocyte adhesion-deficient animals. The syndrome of BLAD may be a suitable model for one of the human leukocyte adhesion deficiency disorders. PMID:7911733

  17. Nicotinamide phosphoribosyltransferase leukocyte overexpression in Graves' opthalmopathy.

    PubMed

    Sawicka-Gutaj, Nadia; Budny, Bartłomiej; Zybek-Kocik, Ariadna; Sowiński, Jerzy; Ziemnicka, Katarzyna; Waligórska-Stachura, Joanna; Ruchała, Marek

    2016-08-01

    To investigate the role of NAMPT/visfatin in euthyroid patients with Graves' disease without (GD) and with Graves' ophthalmopathy (GO), we analyzed NAMPT leukocyte expression and its serum concentration. This was a single-center, cross-sectional study with consecutive enrollment. In total, 149 patients diagnosed with Graves' disease were enrolled in the study. We excluded subjects with hyper- or hypothyroidism, diabetes mellitus, other autoimmune disorders, active neoplastic disease, and infection. The control group was recruited among healthy volunteers adjusted for age, sex, and BMI with normal thyroid function and negative thyroid antibodies. Serum levels of visfatin, TSH, FT4, FT3, antibodies against TSH receptor (TRAb), antithyroperoxidase antibodies, antithyroglobulin antibodies, fasting glucose, and insulin were measured. NAMPT mRNA leukocyte expression was assessed using RT-qPCR. NAMPT/visfatin serum concentration was higher in GD (n = 44) and GO (n = 49) patients than in the control group (n = 40) (p = 0.0275). NAMPT leukocyte expression was higher in patients with GO (n = 30) than in GD patients (n = 27) and the control group (n = 29) (p < 0.0001). Simple linear regression analysis revealed that NAMPT/visfatin serum concentration was significantly associated with GD (β = 1.5723; p = 0.021). When NAMPT leukocyte expression was used as a dependent variable, simple regression analysis found association with TRAb, fasting insulin level, HOMA-IR, GD, and GO. In the stepwise multiple regression analysis, we confirmed the association between higher serum NAMPT/visfatin level and GD (coefficient = 1.5723; p = 0.0212), and between NAMPT leukocyte expression and GO (coefficient = 2.4619; p = 0.0001) and TRAb (coefficient = 0.08742; p = 0.006). Increased NAMPT leukocyte expression in patients with GO might suggest a presently undefined role in the pathogenesis of GO. PMID:26767650

  18. Energy Tracking Software Platform

    SciTech Connect

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  19. Indium-111 leukocyte scanning and fracture healing

    SciTech Connect

    Mead, L.P.; Scott, A.C.; Bondurant, F.J.; Browner, B.D. )

    1990-01-01

    This study was undertaken to determine the specificity of indium-111 leukocyte scans for osteomyelitis when fractures are present. Midshaft tibial osteotomies were performed in 14 New Zealand white rabbits, seven of which were infected postoperatively with Staphylococcus aureus per Norden's protocol. All 14 rabbits were scanned following injection with 75 microCi of indium 111 at 72 h after osteotomy and at weekly intervals for 4 weeks. Before the rabbits were killed, the fracture sites were cultured to document the presence or absence of infection. The results of all infected osteotomy sites were positive, whereas no positive scans were found in the noninfected osteotomies. We concluded from this study that uncomplicated fracture healing does not result in a positive indium-111 leukocyte scan.

  20. Getting Leukocytes to the Site of Inflammation

    PubMed Central

    Muller, W. A.

    2013-01-01

    There is no “response” in either the innate or adaptive immune response unless leukocytes cross blood vessels. They do this through the process of diapedesis, in which the leukocyte moves in ameboid fashion through tightly apposed endothelial borders (paracellular transmigration) and in some cases through the endothelial cell itself (transcellular migration). This review summarizes the steps leading up to diapedesis, then focuses on the molecules and mechanisms responsible for transendothelial migration. Surprisingly, many of the same molecules and mechanisms that regulate paracellular migration also control transcellular migration, including a major role for membrane from the recently described lateral border recycling compartment. A hypothesis that integrates the various known mechanisms of transmigration is proposed. PMID:23345459

  1. Comparison of technetium-99m-HM-PAO leukocytes with indium-111-oxine leukocytes for localizing intraabdominal sepsis

    SciTech Connect

    Mountford, P.J.; Kettle, A.G.; O'Doherty, M.J.; Coakley, A.J. )

    1990-03-01

    Technetium-99m-HM-PAO (({sup 99m}Tc)HM-PAO) leukocyte and indium-111-oxine (111In-oxine) leukocyte scanning were carried out simultaneously in 41 patients at 4 hr and 24 hr after reinjection to determine whether the 4-hr {sup 99m}Tc scan could replace the 24-hr {sup 111}In scan for detecting intraabdominal sepsis. Abdominal infection was confirmed in 12 cases. The 4-hr {sup 99}Tc-leukocyte scan, the 4-hr {sup 111}In-leukocyte scan, and the 24-hr {sup 111}In-leukocyte scan yielded a sensitivity of 100%, 67%, and 100%, respectively, and a specificity of 62%, 90%, and 86%, respectively. The 24-hr {sup 99m}Tc-leukocyte scan also produced a sensitivity of 100%, but it was falsely positive in all 29 cases without infection due to physiologic bowel uptake. False-positive 4-hr {sup 99m}Tc-leukocyte scans were also produced by physiologic bowel uptake in seven cases all of whom had true-negative 4-hr and 24-hr {sup 111}In-leukocyte scans. Because of the high incidence of false-positive 4-hr ({sup 99m}Tc)HM-PAO leukocyte scans, it was concluded that they could not replace 24-hr {sup 111}In-leukocyte scans for detecting intraabdominal sepsis, and that serial {sup 99m}Tc leukocyte scans starting earlier than 4 hr after reinjection must be evaluated.

  2. Bovine leukocyte adhesion deficiency (BLAD): a review.

    PubMed

    Nagahata, Hajime

    2004-12-01

    Bovine leukocyte adhesion deficiency (BLAD) in Holstein cattle is an autosomal recessive congenital disease characterized by recurrent bacterial infections, delayed wound healing and stunted growth, and is also associated with persistent marked neutrophilia. The molecular basis of BLAD is a single point mutation (adenine to guanine) at position 383 of the CD18 gene, which caused an aspartic acid to glycine substitution at amino acid 128 (D128G) in the adhesion molecule CD18. Neutrophils from BLAD cattle have impaired expression of the beta2 integrin (CD11a,b,c/CD18) of the leukocyte adhesion molecule. Abnormalities in a wide spectrum of adherence dependent functions of leukocytes have been fully characterized. Cattle affected with BLAD have severe ulcers on oral mucous membranes, severe periodontitis, loss of teeth, chronic pneumonia and recurrent or chronic diarrhea. Affected cattle die at an early age due to the infectious complications. Holstein bulls, including carrier sires that had a mutant BLAD gene in heterozygote were controlled from dairy cattle for a decade. The control of BLAD in Holstein cattle by publishing the genotypes and avoiding the mating between BLAD carriers was found to be successful. This paper provides an overview of the genetic disease BLAD with reference to the disease in Holstein cattle. PMID:15644595

  3. Blood leukocyte and spleen lymphocyte immune response of spleen lymphocytes and whole blood leukocytes of hamsters

    SciTech Connect

    Peters, B.A.; Sothmann, M.; Wehrenberg, W.B. )

    1989-01-01

    This study was designed to evaluate the effects of chronic physical activity on the immune response of spleen lymphocytes and whole blood leukocytes of hamsters. Animals were kept sedentary or allowed to exercise spontaneously on running wheels for eight weeks. Physically active animals averaged 12 kilometers per day. The immune response of spleen lymphocytes whole blood leukocytes was evaluated by {sup 3}H-thymidine incorporation in response to Concanavalin A or lipopolysaccharide. There was no treatment effect between physically active and sedentary hamster in response of spleen lymphocytes. The immune response of whole blood leukocytes to these mitogens was significantly greater in physically active vs. sedentary hamsters. These results demonstrate that chronic physical activity has the capacity to modulate immunoresponses.

  4. Intravital Microscopy of Leukocyte-endothelial and Platelet-leukocyte Interactions in Mesenterial Veins in Mice.

    PubMed

    Herr, Nadine; Mauler, Maximilian; Bode, Christoph; Duerschmied, Daniel

    2015-01-01

    Intravital microscopy is a method that can be used to investigate different processes in different regions and vessels in living animals. In this protocol, we describe intravital microscopy of mesentery veins. This can be performed in a short period of time with reproducible results showing leukocyte-endothelial interactions in vivo. We describe an inflammatory setting after LPS challenge of the endothelium. But in this model one can apply many different types of inflammatory conditions, like bacterial, chemical or biological and investigate the administration of drugs and their direct effects on the living animal and its impact on leukocyte recruitment. This protocol has been applied successfully to a number of different treatments of mice and their effects on inflammatory response in vessels. Herein, we describe the visualization of leukocytes and platelets by fluorescently labeling these with rhodamine 6G. Additionally, any specific imaging can be performed using targeted fluorescently labeled molecules. PMID:26325284

  5. Leukocyte emigration in normal calves and calves with leukocyte adhesion deficiency.

    PubMed

    Nagahata, H; Masuyama, A; Masue, M; Yuki, M; Higuchi, H; Ohtsuka, H; Kurosawa, T; Sato, H; Noda, H

    1997-12-01

    The emigration of leukocytes from calves with beta 2 integrin deficiency (BLAD) into bronchoalveolar spaces and scraped tissues was compared to that of normal calves. Polymorphonuclear neutrophils were found in bronchoalveolar lavage fluid from BLAD-affected calves showing chronic pneumonia. The neutrophils were complement receptor type 3 (CR3)-negative when characterized by flow cytometric analysis using anti-CD18 monoclonal antibody. Chemiluminescent response mediated by CR3 in neutrophils isolated from bronchoalveolar lavage fluid from BLAD-calves showed similar findings obtained from CR3-deficient neutrophils. Neutrophils from normal calves migrated into scraped tissue which was prepared in an upper gluteal surface area, whereas few leukocytes from calves with BLAD migrated to the scraped tissue, evaluated by skin window (Rebuck) method. These findings confirmed the extravasation of CR3-deficient leukocytes into bronchoalveolar lumen in BLAD calves, and demonstrated in vivo characteristics of extravasating property of normal and CR3-deficient neutrophils into scraped tissues. PMID:9450245

  6. Evaluation of a combined respiratory-gating system comprising the TrueBeam linear accelerator and a new real-time tumor-tracking radiotherapy system: a preliminary study.

    PubMed

    Shiinoki, Takehiro; Kawamura, Shinji; Uehara, Takuya; Yuasa, Yuki; Fujimoto, Koya; Koike, Masahiro; Sera, Tatsuhiro; Emoto, Yuki; Hanazawa, Hideki; Shibuya, Keiko

    2016-01-01

    A combined system comprising the TrueBeam linear accelerator and a new real-time, tumor-tracking radiotherapy system, SyncTraX, was installed in our institution. The goals of this study were to assess the capability of SyncTraX in measuring the position of a fiducial marker using color fluoroscopic images, and to evaluate the dosimetric and geometric accuracy of respiratory-gated radiotherapy using this combined system for the simple geometry. For the fundamental evaluation of respiratory-gated radiotherapy using SyncTraX, the following were performed:1) determination of dosimetric and positional characteristics of sinusoidal patterns using a motor-driven base for several gating windows; 2) measurement of time delay using an oscilloscope; 3) positional verification of sinusoidal patterns and the pattern in the case of a lung cancer patient; 4) measurement of the half-value layer (HVL in mm AL), effective kVp, and air kerma, using a solid-state detector for each fluoroscopic condition, to determine the patient dose. The dose profile in a moving phantom with gated radiotherapy having a gating window ≤ 4 mm was in good agreement with that under static conditions for each photon beam. The total time delay between TrueBeam and SyncTraX was < 227 ms for each photon beam. The mean of the positional tracking error was < 0.4 mm for sinusoidal patterns and for the pattern in the case of a lung cancer patient. The air-kerma rates from one fluoroscopy direction were 1.93 ± 0.01, 2.86 ± 0.01, 3.92 ± 0.04, 5.28 ± 0.03, and 6.60 ± 0.05 mGy/min for 70, 80, 90, 100, and 110 kV X-ray beams at 80 mA, respectively. The combined system comprising TrueBeam and SyncTraX could track the motion of the fiducial marker and control radiation delivery with reasonable accuracy; therefore, this system provides significant dosimetric improvement. However, patient exposure dose from fluoroscopy was not clinically negligible. PMID:27455483

  7. Indium-111 leukocyte imaging in patients with rheumatoid arthritis

    SciTech Connect

    Uno, K.; Matsui, N.; Nohira, K.; Suguro, T.; Kitakata, Y.; Uchiyama, G.; Miyoshi, T.; Uematsu, S.; Inoue, S.; Arimizu, N.

    1986-03-01

    This study evaluates the usefulness of labeled leukocyte imaging in patients with rheumatoid arthritis. In 33 patients, the incidence of pain and swelling in 66 wrist joints and 66 knee joints was compared with the accumulation of (/sup 111/In)leukocytes. No accumulation of (/sup 111/In)leukocytes was seen in any of the patients' wrists (0/12) or knee joints (0/14) when both pain and swelling were absent. In contrast, 93% (25/27) of wrist joints and 80% (24/30) of knee joints with both pain and swelling were positive by (/sup 111/In)leukocyte scintigraphy. There was little correlation between the stage of the disease, as determined by radiography, and (/sup 111/In)leukocyte accumulation. This study suggests that (/sup 111/In)leukocyte imaging may be a reliable procedure for monitoring the activity of rheumatoid arthritis, especially for confirming the lack of an ongoing inflammatory response.

  8. Precision laser automatic tracking system.

    PubMed

    Lucy, R F; Peters, C J; McGann, E J; Lang, K T

    1966-04-01

    A precision laser tracker has been constructed and tested that is capable of tracking a low-acceleration target to an accuracy of about 25 microrad root mean square. In tracking high-acceleration targets, the error is directly proportional to the angular acceleration. For an angular acceleration of 0.6 rad/sec(2), the measured tracking error was about 0.1 mrad. The basic components in this tracker, similar in configuration to a heliostat, are a laser and an image dissector, which are mounted on a stationary frame, and a servocontrolled tracking mirror. The daytime sensitivity of this system is approximately 3 x 10(-10) W/m(2); the ultimate nighttime sensitivity is approximately 3 x 10(-14) W/m(2). Experimental tests were performed to evaluate both dynamic characteristics of this system and the system sensitivity. Dynamic performance of the system was obtained, using a small rocket covered with retroreflective material launched at an acceleration of about 13 g at a point 204 m from the tracker. The daytime sensitivity of the system was checked, using an efficient retroreflector mounted on a light aircraft. This aircraft was tracked out to a maximum range of 15 km, which checked the daytime sensitivity of the system measured by other means. The system also has been used to track passively stars and the Echo I satellite. Also, the system tracked passively a +7.5 magnitude star, and the signal-to-noise ratio in this experiment indicates that it should be possible to track a + 12.5 magnitude star. PMID:20048888

  9. Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Sidorin, Anatoly

    2010-01-01

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  10. Linear Accelerators

    SciTech Connect

    Sidorin, Anatoly

    2010-01-05

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  11. Intraoperative Image-based Multiview 2D/3D Registration for Image-Guided Orthopaedic Surgery: Incorporation of Fiducial-Based C-Arm Tracking and GPU-Acceleration

    PubMed Central

    Armand, Mehran; Armiger, Robert S.; Kutzer, Michael D.; Basafa, Ehsan; Kazanzides, Peter; Taylor, Russell H.

    2012-01-01

    Intraoperative patient registration may significantly affect the outcome of image-guided surgery (IGS). Image-based registration approaches have several advantages over the currently dominant point-based direct contact methods and are used in some industry solutions in image-guided radiation therapy with fixed X-ray gantries. However, technical challenges including geometric calibration and computational cost have precluded their use with mobile C-arms for IGS. We propose a 2D/3D registration framework for intraoperative patient registration using a conventional mobile X-ray imager combining fiducial-based C-arm tracking and graphics processing unit (GPU)-acceleration. The two-stage framework 1) acquires X-ray images and estimates relative pose between the images using a custom-made in-image fiducial, and 2) estimates the patient pose using intensity-based 2D/3D registration. Experimental validations using a publicly available gold standard dataset, a plastic bone phantom and cadaveric specimens have been conducted. The mean target registration error (mTRE) was 0.34 ± 0.04 mm (success rate: 100%, registration time: 14.2 s) for the phantom with two images 90° apart, and 0.99 ± 0.41 mm (81%, 16.3 s) for the cadaveric specimen with images 58.5° apart. The experimental results showed the feasibility of the proposed registration framework as a practical alternative for IGS routines. PMID:22113773

  12. Cervical leukocytes and spontaneous preterm birth

    PubMed Central

    Hunter, Patricia J.; Sheikh, Sairah; David, Anna L.; Peebles, Donald M.; Klein, Nigel

    2016-01-01

    The objective was to characterise cervical leukocyte populations and inflammatory mediators associated with term and recurrent spontaneous preterm birth (SPTB) in pregnant women with a history of SPTB. A prospective observational study was undertaken on 120 women with a history of SPTB. A cytobrush was used to sample cells from the cervix at 12–25 weeks’ gestation. Cells were enumerated and characterised by flow cytometry. Cytokines and chemokines were also measured. Participants were then grouped according to delivery at term (>36 + 6 weeks), late SPTB (34–36 + 6 weeks) or early SPTB (<34 weeks). Differences in leukocyte sub-populations, cytokine and chemokine levels were compared with outcome. Cervical leukocytes comprised up to 60% of the host-derived cells. Most of these (90–100%) were polymorphonuclear cells (PMN). Most of the remaining cells were mucosal macrophages expressing CD68 and CD103 in addition to markers shared with blood-borne monocytes. Failure to detect cervical macrophages in at least 250,000 cervical epithelial cells was a feature of women who experienced early SPTB (6 out of 6 cases, 95% CI 61–100%) compared with 34% (30 out of 88 cases, 95% CI 25–43%, P < 0.001) of women delivering after 34 weeks. CCL2 (MCP-1) was also low in SPTB before 34 weeks and levels above 75 ng/g and/or the presence of macrophages increased the specificity for birth after 34 weeks from 66% to 82% (55 out of 67 cases, 95% CI 73–91%). Absence of cervical macrophages and low CCL2 may be features of pregnancies at risk of early SPTB. PMID:26637953

  13. Imaging of Leukocyte Trafficking in Alzheimer's Disease.

    PubMed

    Pietronigro, Enrica; Zenaro, Elena; Constantin, Gabriela

    2016-01-01

    Alzheimer's disease (AD) is the most common neurodegenerative disorder and is characterized by a progressive decline of cognitive functions. The neuropathological features of AD include amyloid beta (Aβ) deposition, intracellular neurofibrillary tangles derived from the cytoskeletal hyperphosphorylated tau protein, amyloid angiopathy, the loss of synapses, and neuronal degeneration. In the last decade, inflammation has emerged as a key feature of AD, but most studies have focused on the role of microglia-driven neuroinflammation mechanisms. A dysfunctional blood-brain barrier has also been implicated in the pathogenesis of AD, and several studies have demonstrated that the vascular deposition of Aβ induces the expression of adhesion molecules and alters the expression of tight junction proteins, potentially facilitating the transmigration of circulating leukocytes. Two-photon laser scanning microscopy (TPLSM) has become an indispensable tool to dissect the molecular mechanisms controlling leukocyte trafficking in the central nervous system (CNS). Recent TPLSM studies have shown that vascular deposition of Aβ in the CNS promotes intraluminal neutrophil adhesion and crawling on the brain endothelium and also that neutrophils extravasate in the parenchyma preferentially in areas with Aβ deposits. These studies have also highlighted a role for LFA-1 integrin in neutrophil accumulation in the CNS of AD-like disease models, revealing that LFA-1 inhibition reduces the corresponding cognitive deficit and AD neuropathology. In this article, we consider how current imaging techniques can help to unravel new inflammation mechanisms in the pathogenesis of AD and identify novel therapeutic strategies to treat the disease by interfering with leukocyte trafficking mechanisms. PMID:26913031

  14. A role for leukocyte-endothelial adhesion mechanisms in epilepsy

    PubMed Central

    Fabene, Paolo F.; Mora, Graciela Navarro; Martinello, Marianna; Rossi, Barbara; Merigo, Flavia; Ottoboni, Linda; Bach, Simona; Angiari, Stefano; Benati, Donatella; Chakir, Asmaa; Zanetti, Lara; Schio, Federica; Osculati, Antonio; Marzola, Pasquina; Nicolato, Elena; Homeister, Jonathon W.; Xia, Lijun; Lowe, John B.; McEver, Rodger P.; Osculati, Francesco; Sbarbati, Andrea; Butcher, Eugene C.; Constantin, Gabriela

    2009-01-01

    The mechanisms involved in the pathogenesis of epilepsy, a chronic neurological disorder that affects approximately 1 percent of the world population, are not well understood1–3. Using a mouse model of epilepsy, we show that seizures induce elevated expression of vascular cell adhesion molecules and enhanced leukocyte rolling and arrest in brain vessels mediated by the leukocyte mucin P-selectin glycoprotein ligand-1 (PSGL-1) and leukocyte integrins α4β1 and αLβ2. Inhibition of leukocyte-vascular interactions either with blocking antibodies, or in mice genetically deficient in functional PSGL-1, dramatically reduced seizures. Treatment with blocking antibodies following acute seizures prevented the development of epilepsy. Neutrophil depletion also inhibited acute seizure induction and chronic spontaneous recurrent seizures. Blood-brain barrier (BBB) leakage, which is known to enhance neuronal excitability, was induced by acute seizure activity but was prevented by blockade of leukocyte-vascular adhesion, suggesting a pathogenetic link between leukocyte-vascular interactions, BBB damage and seizure generation. Consistent with potential leukocyte involvement in the human, leukocytes were more abundant in brains of epileptics than of controls. Our results suggest leukocyte-endothelial interaction as a potential target for the prevention and treatment of epilepsy. PMID:19029985

  15. PARTICLE BEAM TRACKING CIRCUIT

    DOEpatents

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  16. Factor Associated with Neutral Sphingomyelinase Activity Mediates Navigational Capacity of Leukocytes Responding to Wounds and Infection: Live Imaging Studies in Zebrafish Larvae

    PubMed Central

    Boecke, Alexandra; Sieger, Dirk; Neacsu, Cristian Dan; Kashkar, Hamid

    2012-01-01

    Factor associated with neutral sphingomyelinase activity (FAN) is an adaptor protein that specifically binds to the p55 receptor for TNF (TNF-RI). Our previous investigations demonstrated that FAN plays a role in TNF-induced actin reorganization by connecting the plasma membrane with actin cytoskeleton, suggesting that FAN may impact on cellular motility in response to TNF and in the context of immune inflammatory conditions. In this study, we used the translucent zebrafish larvae for in vivo analysis of leukocyte migration after morpholino knockdown of FAN. FAN-deficient zebrafish leukocytes were impaired in their migration toward tail fin wounds, leading to a reduced number of cells reaching the wound. Furthermore, FAN-deficient leukocytes show an impaired response to bacterial infections, suggesting that FAN is generally required for the directed chemotactic response of immune cells independent of the nature of the stimulus. Cell-tracking analysis up to 3 h after injury revealed that the reduced number of leukocytes is not due to a reduction in random motility or speed of movement. Leukocytes from FAN-deficient embryos protrude pseudopodia in all directions instead of having one clear leading edge. Our results suggest that FAN-deficient leukocytes exhibit an impaired navigational capacity, leading to a disrupted chemotactic response. PMID:22802420

  17. Delay discounting, genetic sensitivity, and leukocyte telomere length.

    PubMed

    Yim, Onn-Siong; Zhang, Xing; Shalev, Idan; Monakhov, Mikhail; Zhong, Songfa; Hsu, Ming; Chew, Soo Hong; Lai, Poh San; Ebstein, Richard P

    2016-03-01

    In a graying world, there is an increasing interest in correlates of aging, especially those found in early life. Leukocyte telomere length (LTL) is an emerging marker of aging at the cellular level, but little is known regarding its link with poor decision making that often entails being overly impatient. Here we investigate the relationship between LTL and the degree of impatience, which is measured in the laboratory using an incentivized delay discounting task. In a sample of 1,158 Han Chinese undergraduates, we observe that steeper delay discounting, indexing higher degree of impatience, is negatively associated with LTL. The relationship is robust after controlling for health-related variables, as well as risk attitude-another important determinant of decision making. LTL in females is more sensitive to impatience than in males. We then asked if genes possibly modulate the effect of impatient behavior on LTL. The oxytocin receptor gene (OXTR) polymorphism rs53576, which has figured prominently in investigations of social cognition and psychological resources, and the estrogen receptor β gene (ESR2) polymorphism rs2978381, one of two gonadal sex hormone genes, significantly mitigate the negative effect of impatience on cellular aging in females. The current results contribute to understanding the relationship between preferences in decision making, particularly impatience, and cellular aging, for the first time to our knowledge. Notably, oxytocin and estrogen receptor polymorphisms temper accelerated cellular aging in young females who tend to make impatient choices. PMID:26903639

  18. Factors affecting leukocyte count in healthy adults.

    PubMed

    Carel, R S; Eviatar, J

    1985-09-01

    The relationships between white blood cell (WBC) count, smoking, and other health variables were determined among 35,000 apparently healthy men and women. The effect of smoking on the WBC count was greater than that of all other variables. The leukocyte level and the variance in WBC count values increased with increased smoking intensity. The relationship between smoking intensity and leukocyte level is expressed quantitatively by the following regression equation: WBC (10(3)/mm3) = 7.1 + 0.05(SM), where SM has seven values according to the smoking level. Multiple regression analysis with additional variables other than smoking did not much improve the predictive value of the equation. The effect of smoking on WBC count could be only partially explained by an inflammatory process, e.g., chronic bronchitis. Relationships of statistical significance (but mostly with r values of less than 0.10) were found between WBC count and the following variables: hemoglobin, heart rate, weight (or Quetelet index), cholesterol, uric acid, creatinine, sex, ethnic origin, systolic blood pressure, height, blood sugar, and diastolic blood pressure. The normal WBC count range for smokers differs from that of nonsmokers and is shifted to the right according to the smoking level. This may have both a diagnostic and prognostic significance in different clinical settings. PMID:4070192

  19. Can Accelerators Accelerate Learning?

    NASA Astrophysics Data System (ADS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-03-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ) [1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  20. PARTICLE ACCELERATOR

    DOEpatents

    Teng, L.C.

    1960-01-19

    ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

  1. The effects of stress on the enzymes of peripheral leukocytes

    NASA Technical Reports Server (NTRS)

    Leise, E. M.; Gray, I.

    1973-01-01

    Previous work showed an early response of rabbit and human leukocyte enzymes to the stress of bacterial infection. Since these represented a mixed population of leukocytes and since polymorphonuclear leukocytes (PMN) increased in these preparations, it was necessary to establish whether the observed increase in lactate dehydrenase (LDH) and protein was the result of an increase in any one particular cell type or in all cells. The need for the development of a simple reproducible method for the differential separation of peripheral leukocytes for the furtherance of our own studies was apparent. It was also becoming increasingly apparent that morphologically similar cells, such as small lymphocytes (L) and macrophages, were capable of different biological functions. A dextran gradient centrifugation method was developed which has provided an easily reproducible technique for separating L from PMN. During the course of this work, in which over 250 rabbits were examined, the pattern of daily leukocyte protein and enzyme variation became increasingly more apparent. This information could have some impact on future work with leukocyte enzymes, by our group and by other workers. The differences in normal protein and enzyme levels maintained by some individuals, and some inbred strains, were evaluated and reported separately. It has been shown that one type of leukocyte may react more to a given stress than other leukocytes.

  2. Alteration of rat polymorphonuclear leukocyte function after thermal injury.

    PubMed

    Gruber, D F; D'Alesandro, M M

    1989-01-01

    One portion of host defense to bacterial challenge(s) involves the activation and infiltration of endogenous polymorphonuclear leukocytes. Thermal injuries are frequently associated with immunologic abnormalities including alterations of polymorphonuclear leukocyte-associated nonspecific resistance. We examined isolated peripheral rat polymorphonuclear leukocytes for alterations in membrane potential, oxidative capability, and locomotor function after the experimental application of 20% full-thickness body surface area thermal injury. Thermal injury resulted in significant reductions of peripheral red blood cell concentration(s) and increases in leukocyte and platelet concentrations for 42 days after injury. In addition to the quantitative changes, polymorphonuclear leukocytes also demonstrated altered qualitative functions. Compared with phorbol myristate acetate-induced activation of normal cells, polymorphonuclear leukocyte membranes from thermal-injured animals were electrophysiologically less responsive for 3 weeks after injury. The ability of polymorphonuclear leukocytes to produce intracellular H2O2, a measure of oxidative function, was also significantly decreased for 7 days after injury. The paradox in this paradigm of thermal injury was the demonstration of peripheral polymorphonuclear leukocyte quantitative increases with concurrent significant qualitative impairment. Qualitative lesions included altered states of membrane depolarization and depressed oxidative capability that may individually, or collectively, reduce nonspecific immune capabilities of the host to levels that are inadequate to combat infection. PMID:2793916

  3. [Bovine leukocyte adhesion deficiency: clinical picture and differential diagnosis].

    PubMed

    Lienau, A; Stöber, M; Kehrli, M E; Tammen, I; Schwenger, B; Kuczka, A; Pohlenz, J

    1994-10-01

    The pathological clinical and laboratory findings obtained in 50 calves and young cattle affected with Bovine Leukocyte Adhesion Deficiency are compared with those found in 114 calves and young cattle showing marked neutrophil leukocytosis of other origin (age: < 2 years; leukocyte count: > 30,000 per microl; percentage of lymphocytes: < 55%). PMID:7851303

  4. 21 CFR 864.7675 - Leukocyte peroxidase test.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Leukocyte peroxidase test. 864.7675 Section 864... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... peroxidase activity as evidenced by staining. The results of this test are used in the differential...

  5. 21 CFR 864.7675 - Leukocyte peroxidase test.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Leukocyte peroxidase test. 864.7675 Section 864... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... peroxidase activity as evidenced by staining. The results of this test are used in the differential...

  6. 21 CFR 864.7675 - Leukocyte peroxidase test.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Leukocyte peroxidase test. 864.7675 Section 864... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... peroxidase activity as evidenced by staining. The results of this test are used in the differential...

  7. 21 CFR 864.7675 - Leukocyte peroxidase test.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Leukocyte peroxidase test. 864.7675 Section 864... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... peroxidase activity as evidenced by staining. The results of this test are used in the differential...

  8. 21 CFR 864.7675 - Leukocyte peroxidase test.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Leukocyte peroxidase test. 864.7675 Section 864... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... peroxidase activity as evidenced by staining. The results of this test are used in the differential...

  9. Visualizing leukocyte trafficking in the living brain with 2-photon intravital microscopy

    PubMed Central

    Pai, Saparna; Danne, Karyn J.; Qin, Jim; Cavanagh, Lois L.; Smith, Adrian; Hickey, Michael J.; Weninger, Wolfgang

    2012-01-01

    Intravital imaging of the superficial brain tissue in mice represents a powerful tool for the dissection of the cellular and molecular cues underlying inflammatory and infectious central nervous system (CNS) diseases. We present here a step-by-step protocol that will enable a non-specialist to set up a two-photon brain-imaging model. The protocol offers a two-part approach that is specifically optimized for imaging leukocytes but can be easily adapted to answer varied CNS-related biological questions. The protocol enables simultaneous visualization of fluorescently labeled immune cells, the pial microvasculature and extracellular structures such as collagen fibers at high spatial and temporal resolution. Intracranial structures are exposed through a cranial window, and physiologic conditions are maintained during extended imaging sessions via continuous superfusion of the brain surface with artificial cerebrospinal fluid (aCSF). Experiments typically require 1–2 h of preparation, which is followed by variable periods of immune cell tracking. Our methodology converges the experience of two laboratories over the past 10 years in diseased animal models such as cerebral ischemia, lupus, cerebral malaria, and toxoplasmosis. We exemplify the utility of this protocol by tracking leukocytes in transgenic mice in the pial vessels under steady-state conditions. PMID:23316136

  10. Degradation of thyroid hormones by phagocytosing human leukocytes.

    PubMed

    Klebanoff, S J; Green, W L

    1973-01-01

    Thyroxine (T(4)) and triiodothyronine (T(9)) are rapidly degraded by a purified preparation of myeloperoxidase (MPO) and H(2)O(2) with the formation of iodide and material which remains at the origin on paper chromatography. Deiodination by MPO and H(2)O(2) occurs more readily at pH 7.0 than at pH 5.0 in contrast to iodination by this system which is known to occur more readily at pH 5.0 than at pH 7.0. Degradation is inhibited by azide, cyanide, ascorbic acid, and propylthiouracil. Methimazole stimulates deiodination by MPO and H(2)O(2) but inhibits this reaction when MPO is replaced by lactoperoxidase or horseradish peroxidase.Intact human leukocytes, in the resting state, degrade T(4) and T(3) slowly: degradation, however, is increased markedly during phagocytosis of preopsonized particles. Serum inhibits this reaction. T(3) can be detected as a minor product of T(4) degradation. Proteolytic digestion of the reaction products increases the recovery of monoiodotyrosine. The fixation of iodine in the cytoplasm of leukocytes which contain ingested bacteria was detected radioautographically. Chronic granulomatous disease leukocytes, which are deficient in H(2)O(2) formation, degrade T(4) and T(3) poorly during phagocytosis. MPO-deficient leukocytes degrade the thyroid hormones at a slower rate than do normal leukocytes although considerable degradation is still observed. Azide, cyanide, ascorbic acid, and propylthiouracil which inhibit certain peroxidasecatalyzed reactions inhibit degradation by normal leukocytes; however, inhibition is incomplete. Formation of iodinated origin material is inhibited to a greater degree by azide, cyanide, and propylthiouracil than is deiodination. Methimazole inhibits the formation of iodinated origin material by both normal and MPO-deficient leukocytes. However, deiodination by normal leukocytes is stimulated and that of MPO-deficient leukocytes is unaffected by methimazole. Hypoxia inhibits the degradation of T(4) and T(3) by

  11. [Polar coordinates representation based leukocyte segmentation of microscopic cell images].

    PubMed

    Gu, Guanghua; Cui, Dong; Hao, Lianwang

    2010-12-01

    We propose an algorithm for segmentation of the overlapped leukocyte in the microscopic cell image. The histogram of the saturation channel in the cell image is smoothed to obtain the meaningful global valley point by the fingerprint smoothing method, and then the nucleus can be segmented. A circular region, containing the entire regions of the leukocyte, is marked off according to the equivalent sectional radius of the nucleus. Then, the edge of the overlapped leukocyte is represented by polar coordinates. The overlapped region by the change of the polar angle of the edge pixels is determined, and the closed edge of the leukocyte integrating the gradient information of the overlapped region is reconstructed. Finally, the leukocyte is exactly extracted. The experimental results show that our method has good performance in terms of recall ratio, precision ratio and pixel error ratio. PMID:21374971

  12. Cannabinoid-receptor expression in human leukocytes.

    PubMed

    Bouaboula, M; Rinaldi, M; Carayon, P; Carillon, C; Delpech, B; Shire, D; Le Fur, G; Casellas, P

    1993-05-15

    Marijuana and many of its constituent cannabinoids influence the central nervous system (CNS), probably through the cannabinoid receptor, which has recently been cloned in rat and human. While numerous reports have also described effects of cannabinoids on the immune system, the observation of both mRNA and cannabinoid receptor has hitherto been exclusively confined to the brain, a reported detection in the testis being the sole example of its presence at the periphery. Here we report the expression of the cannabinoid receptor on human immune tissues using a highly sensitive polymerase-chain-reaction-based method for mRNA quantification. We show that, although present in a much lower abundance than in brain, cannabinoid receptor transcripts are found in human spleen, tonsils and peripheral blood leukocytes. The distribution pattern displays important variations of the mRNA level for the cannabinoid receptor among the main human blood cell subpopulations. The rank order of mRNA levels in these cells is B cells > natural killer cells > or = polymorphonuclear neutrophils > or = T8 cells > monocytes > T4 cells. Cannabinoid-receptor mRNA, which is also found in monocytic, as well as T and B leukemia cell lines but not in Jurkat cells, presents a great diversity of expression on these cells as well, B-cell lines expressing a much higher level than T-cell lines. The cannabinoid receptor PCR products from leukocytes and brain are identical both in size and sequence suggesting a strong similarity between central and peripheral cannabinoid receptors. The expression of this receptor was demonstrated on membranes of the myelomonocytic U937 cells using the synthetic cannabinoid [3H]CP-55940 as ligand. The Kd determined from Scatchard analysis was 0.1 nM and the Bmax for membranes was 525 fmol/mg protein. The demonstration of cannabinoid-receptor expression at both mRNA and protein levels on human leukocytes provides a molecular basis for cannabinoid action on these cells. PMID

  13. Derailing Tracking.

    ERIC Educational Resources Information Center

    Black, Susan

    1993-01-01

    Reviews recent research on student achievement, self-concept, and curriculum and instruction showing the ineffectiveness of tracking and ability grouping. Certain court rulings show that tracking violates the equal protection clause of the Fourteenth Amendment. Innovative alternatives include cooperative learning, mastery learning, peer tutoring,…

  14. Beyond Tracking.

    ERIC Educational Resources Information Center

    Bates, Percy; And Others

    1992-01-01

    On the surface, educational tracking may seem like a useful tool for allowing students to work at their own pace, and to avoid discouraging competition, but abuses of the tracking idea have arisen through biased placement practices that have denied equal access to education for minority students. The articles in this issue explore a number of…

  15. Margination of leukocytes in blood flow through small tubes.

    PubMed

    Goldsmith, H L; Spain, S

    1984-03-01

    Leukocyte margination in the vessels of the microcirculation has been attributed to a flow-dependent interaction with red cells. To determine the extent of this effect, experiments with human blood were done in 100- to 180-micron tubes to detect changes in cell distribution as a function of hematocrit and flow rate. Using a flow visualization technique, the leukocyte concentration distribution was determined in 45% ghost cell suspensions. Migration of cells toward the wall was observed at centerline velocities greater than 1 mm sec-1 and increased with increasing flow rate. The effect was probably due to a more rapid inward migration of ghosts than leukocytes because of fluid inertia and cell density differences. Experiments were therefore carried out in whole blood at hematocrits from 20 to 60%, measuring the number concentration of leukocytes and erythrocytes within the tube, nt, and comparing it to that in the infusing reservoir, no, (Fahraeus effect). At mean tube shear rates G less than 100 sec-1, nt/no less than 1 for both leukocytes and erythrocytes showing net migration of cells away from the wall, although at nearly all hematocrits there was an enrichment of leukocytes relative to erythrocytes in the tubes. At G less than 50 sec-1, nt/no remained less than 1 for erythrocytes but increased to greater than 1 for leukocytes showing migration toward the wall, the increase being greatest at 20% hematocrit in the 100-micron tubes. The nature of the effect was revealed by cine films which showed that, as the flow rate decreased, erythrocytes formed rouleaux which migrated inward creating a core and displacing leukocytes to the periphery. In control experiments using washed blood cells in phosphate buffer-albumin, nt/no less than 1 for both leukocytes and erythrocytes at all G and hematocrits, and leukocytes were now distributed. Cine films of washed blood confirmed that, in the absence of rouleaux, no significant inward migration of erythrocytes occurred. PMID

  16. Factors influencing human leukocyte adherence in vitro.

    PubMed

    Stepniewicz, W; Tchórzewski, H; Luciak, M

    1983-01-01

    Studies were performed on factors influencing leucocyte adherence in vitro. Blood condensation was found to increase leukocyte adherence. Addition of heparin, dextran or ethanol caused a significant reduction of white blood cell count in blood samples in comparison with blood mixed with sodium EDTA or ACD solution. This suggests the existence of two granulocyte subpopulations; viz, rapidly adhering and slowly adhering. Heparin enhanced granulocyte adherence, while dextran and ethanol decreased it. Five-day storage of ACD blood led to a decrease in granulocyte adherence, while addition of heparin or histamine to ACD blood prevented this change to occur. The glucose concentration of 1,000 mg/dl augmented granulocyte adherence, while higher glucose concentrations induced its progressive fall below the control values. There was no significant change of lymphocyte adherence during the experiments. PMID:6194070

  17. [Detection and typing for swine leukocyte antigen].

    PubMed

    Li, Hua; Luo, Huai-Rong; Zhang, Ya-Ping; Qiu, Xiang-Pin; Ye, Chun

    2004-03-01

    Traditionally the cluster of swine leukocyte antigen (SLA) was typed by serological, cytological and biochemical methods. Many special molecular typing methods have been developed with the progress of molecular biological technology, such as PCR-RFLP, PCR-SSCP , MS and DNA sequencing. Here we discussed the advantages and disadvantages of each method based on the polymorphic and conservative (from the functional aspect, such as supertype and supermotif) characteristics of SLA, and illustrated the development of typing for SLA in the future. In addition, we pointed out the editorial mistakes about the serological haplotype of SLA in reference book and emphasized that the accurate polymorphism of SLA-DQB gene must be based on the cloning sequencing. PMID:15639990

  18. Leukocytic oxygen activation and microbicidal oxidative toxins.

    PubMed

    Hurst, J K; Barrette, W C

    1989-01-01

    Following a brief introduction of cellular response to stimulation comprising leukocyte activation, three major areas are discussed: (1) the neutrophil oxidase; (2) myeloperoxidase (MPO)-dependent oxidative microbicidal reactions; and (3) MPO-independent oxidative reactions. Topics included in section (A) are current views on the activation mechanism, redox composition, structural and topographic organization of the oxidase, and its respiratory products. In section (B), emphasis is placed on recent research on cidal mechanisms of HOCl, including the oxidative biochemistry of active chlorine compounds, identification of sites of lesions in bacteria, and attendant metabolic consequences. In section (C), we review the (bio)chemistry of H2O2 and .OH microbicidal reactions, with particular attention being given to addressing the controversial issue of probe methods to identify .OH radical and critical assessment of the recent proposal that MPO-independent killing arises from site-specific metal-catalyzed Fenton-type chemistry. PMID:2548810

  19. Rover tracks

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Tracks made by the Sojourner rover are visible in this image, taken by one of the cameras aboard Sojourner on Sol 3. The tracks represent the rover maneuvering towards the rock dubbed 'Barnacle Bill.' The rover, having exited the lander via the rear ramp, first traveled towards the right portion of the image, and then moved forward towards the left where Barnacle Bill sits. The fact that the rover was making defined tracks indicates that the soil is made up of particles on a micron scale.

    Mars Pathfinder was developed and managed by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration.

  20. NEKF IMM tracking algorithm

    NASA Astrophysics Data System (ADS)

    Owen, Mark W.; Stubberud, Allen R.

    2003-12-01

    Highly maneuvering threats are a major concern for the Navy and the DoD and the technology discussed in this paper is intended to help address this issue. A neural extended Kalman filter algorithm has been embedded in an interacting multiple model architecture for target tracking. The neural extended Kalman filter algorithm is used to improve motion model prediction during maneuvers. With a better target motion mode, noise reduction can be achieved through a maneuver. Unlike the interacting multiple model architecture which uses a high process noise model to hold a target through a maneuver with poor velocity and acceleration estimates, a neural extended Kalman filter is used to predict corrections to the velocity and acceleration states of a target through a maneuver. The neural extended Kalman filter estimates the weights of a neural network, which in turn are used to modify the state estimate predictions of the filter as measurements are processed. The neural network training is performed on-line as data is processed. In this paper, the simulation results of a tracking problem using a neural extended Kalman filter embedded in an interacting multiple model tracking architecture are shown. Preliminary results on the 2nd Benchmark Problem are also given.

  1. NEKF IMM tracking algorithm

    NASA Astrophysics Data System (ADS)

    Owen, Mark W.; Stubberud, Allen R.

    2004-01-01

    Highly maneuvering threats are a major concern for the Navy and the DoD and the technology discussed in this paper is intended to help address this issue. A neural extended Kalman filter algorithm has been embedded in an interacting multiple model architecture for target tracking. The neural extended Kalman filter algorithm is used to improve motion model prediction during maneuvers. With a better target motion mode, noise reduction can be achieved through a maneuver. Unlike the interacting multiple model architecture which uses a high process noise model to hold a target through a maneuver with poor velocity and acceleration estimates, a neural extended Kalman filter is used to predict corrections to the velocity and acceleration states of a target through a maneuver. The neural extended Kalman filter estimates the weights of a neural network, which in turn are used to modify the state estimate predictions of the filter as measurements are processed. The neural network training is performed on-line as data is processed. In this paper, the simulation results of a tracking problem using a neural extended Kalman filter embedded in an interacting multiple model tracking architecture are shown. Preliminary results on the 2nd Benchmark Problem are also given.

  2. Myeloperoxidase-mediated activation of xenobiotics by human leukocytes.

    PubMed

    Hofstra, A H; Uetrecht, J P

    1993-10-01

    Peripheral blood leukocytes contain a variety of enzymes that are capable of metabolising xenobiotics. The enzyme myeloperoxidase (MPO) appears to be the most important for drug metabolism. MPO is a peroxidase/oxidase and generates the powerful oxidant hypochlorous acid. MPO- or MPO-generated oxidants are capable of oxidizing a wide variety of compounds and a broad range of functional groups, especially those that contain nitrogen and sulfur. Leukocytes have a role in immune response; therefore, reactive intermediates generated by leukocyte metabolism of xenobiotics may have a role in idiosyncratic drug reactions, particularly those that are immune-mediated such as drug-induced lupus or agranulocytosis. PMID:8236277

  3. Uptake of indium-111-labeled leukocytes by brain metastasis

    SciTech Connect

    Balachandran, S.; Husain, M.M.; Adametz, J.R.; Pallin, J.S.; Angtuaco, T.L.; Boyd, C.M.

    1987-04-01

    Uptake of indium-labeled leukocytes was seen in two cases of histologically proven brain metastasis. In one, this led to misdiagnosis of the lesion as an abscess. On histological evaluation, a large number of white blood cells or macrophages was seen at the neoplastic sites. Reasons for leukocyte accumulation around metastatic brain neoplasms are discussed. In contrast to the current reports that indium-labeled leukocyte scans can differentiate intracranial infection from tumor, these cases demonstrate their lack of specificity in the detection of brain abscess.

  4. Endothelial cells proactively form microvilli-like membrane projections upon intercellular adhesion molecule 1 engagement of leukocyte LFA-1.

    PubMed

    Carman, Christopher V; Jun, Chang-Duk; Salas, Azucena; Springer, Timothy A

    2003-12-01

    Specific leukocyte/endothelial interactions are critical for immunity and inflammation, yet the molecular details of this interaction interface remain poorly understood. Thus, we investigated, with confocal microscopy, the distribution dynamics of the central adhesion molecules ICAM-1 and LFA-1 in this context. Monolayers of activated HUVECs stained with fluorescent anti-ICAM-1 Fabs or Chinese hamster ovary-K1 cells expressing ICAM-1-green fluorescent protein were allowed to bind LFA-1-bearing monocytes, neutrophils, or K562 LFA-1 transfectants. ICAM-1 was rapidly relocalized to newly formed microvilli-like membrane projections in response to binding LFA-1 on leukocytes. These ICAM-1-enriched projections encircled the leukocytes extending up their sides and clustered LFA-1 underneath into linear tracks. Projections formed independently of VCAM-1/very late Ag 4 interactions, shear, and proactive contributions from the LFA-1-bearing cells. In the ICAM-1-bearing endothelial cells, projections were enriched in actin but not microtubules, required intracellular calcium, and intact microfilament and microtubule cytoskeletons and were independent of Rho/Rho kinase signaling. Disruption of these projections with cytochalasin D, colchicine, or BAPTA-AM had no affect on firm adhesion. These data show that in response to LFA-1 engagement the endothelium proactively forms an ICAM-1-enriched cup-like structure that surrounds adherent leukocytes but is not important for firm adhesion. This finding leaves open a possible role in leukocyte transendothelial migration, which would be consistent with the geometry and kinetics of formation of the cup-like structure. PMID:14634129

  5. Galilean Tracks in the Physics Lab

    ERIC Educational Resources Information Center

    Hellman, Walter

    2011-01-01

    Variations of Galileo's famous track experiments in acceleration are commonly performed in high school and college. The purpose of this article is to present a sequence of three low-tech basic kinematics experiments using Galilean tracks that can be set up extremely quickly and yet generally yield excellent results. A low-cost construction method…

  6. TRACK : the new beam dynamics code.

    SciTech Connect

    Aseev, V. N.; Ostroumov, P. N.; Lessner, E. S.; Mustapha, B.; Physics

    2005-01-01

    The new ray-tracing code TRACK originally developed to fulfill the special requirements of the RIA accelerator systems is a general beam dynamics code. It is currently being used for the design and simulation of future proton and heavy-ion linacs at several Labs. This paper presents a general description of the code TRACK emphasizing its main new features and recent updates.

  7. Precision CW laser automatic tracking system investigated

    NASA Technical Reports Server (NTRS)

    Lang, K. T.; Lucy, R. F.; Mcgann, E. J.; Peters, C. J.

    1966-01-01

    Precision laser tracker capable of tracking a low acceleration target to an accuracy of about 20 microradians rms is being constructed and tested. This laser tracking has the advantage of discriminating against other optical sources and the capability of simultaneously measuring range.

  8. Accelerator simulation using computers

    SciTech Connect

    Lee, M.; Zambre, Y.; Corbett, W.

    1992-01-01

    Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exits that simulate the propagation of a beam in a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a multi-track'' simulation and analysis code can be used for these applications.

  9. Accelerator simulation using computers

    SciTech Connect

    Lee, M.; Zambre, Y.; Corbett, W.

    1992-01-01

    Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exits that simulate the propagation of a beam in a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a ``multi-track`` simulation and analysis code can be used for these applications.

  10. Influence of Magnetite Nanoparticles on Human Leukocyte Activity

    NASA Astrophysics Data System (ADS)

    Džarová, Anežka; Dubničková, Martina; Závišová, Vlasta; Koneracká, Martina; Kopčanský, Peter; Gojzewski, Hubert; Timko, Milan

    2010-12-01

    Chemically synthesized magnetite particles coated by sodium oleate and PEG (MNP), and magnetosomes (MS) influence the process of phagocytosis and the metabolic activity (lysozyme and peroxidase activity) in leukocytes. Lysozyme activity is oxygen-independent liquidation mechanisms of engulfed microorganism, peroxidase activity is an oxygen-dependent mechanism. Both tested types of nanoparticles lysed leukocyte cells during incubation. MNP at concentrations of 10 and 20 μg/mL lysed almost all leukocytes and their cell viability was in the 14±0.05% range. On the other hand MS begin to influence leukocytes activity at the concentration of 1 μg/ml and this influence grows with increasing concentration up to 20 μg/ml. MS are more suitable for biological applications than MNP which are more aggressive material than MS. MS should not be used above 10 μg/mL.

  11. Osteomyelitis complicating fracture: pitfalls of /sup 111/In leukocyte scintigraphy

    SciTech Connect

    Kim, E.E.; Pjura, G.A.; Lowry, P.A.; Gobuty, A.H.; Traina, J.F.

    1987-05-01

    /sup 111/In-labeled leukocyte imaging has shown greater accuracy and specificity than alternative noninvasive methods in the detection of uncomplicated osteomyelitis. Forty patients with suspected osteomyelitis complicating fractures (with and without surgical intervention) were evaluated with /sup 111/In-labeled leukocytes. All five patients with intense focal uptake, but only one of 13 with no uptake, had active osteomyelitis. However, mild to moderate /sup 111/In leukocyte uptake, observed in 22 cases, indicated the presence of osteomyelitis in only four of these; the other false-positive results were observed in noninfected callus formation, heterotopic bone formation, myositis ossificans, and sickle-cell disease. These results suggest that /sup 111/In-labeled leukocyte imaging is useful for the evaluation of suspected osteomyelitis complicating fracture but must be used in conjunction with clinical and radiographic correlation to avoid false-positive results.

  12. Clinical imaging with indium-111 leukocytes: uptake in bowel infarction

    SciTech Connect

    Gray, H.W.; Cuthbert, I.; Richards, J.R.

    1981-08-01

    Leukocytes labeled with indium-111 accumulated in an area of small-bowel infarction, mimicking a paracolic abscess. Evidence of subacute bowel obstruction should alert the nuclear medicine physician to the former possibility.

  13. Plasma accelerators

    SciTech Connect

    Ruth, R.D.; Chen, P.

    1986-03-01

    In this paper we discuss plasma accelerators which might provide high gradient accelerating fields suitable for TeV linear colliders. In particular we discuss two types of plasma accelerators which have been proposed, the Plasma Beat Wave Accelerator and the Plasma Wake Field Accelerator. We show that the electric fields in the plasma for both schemes are very similar, and thus the dynamics of the driven beams are very similar. The differences appear in the parameters associated with the driving beams. In particular to obtain a given accelerating gradient, the Plasma Wake Field Accelerator has a higher efficiency and a lower total energy for the driving beam. Finally, we show for the Plasma Wake Field Accelerator that one can accelerate high quality low emittance beams and, in principle, obtain efficiencies and energy spreads comparable to those obtained with conventional techniques.

  14. Neutrophil Leukocyte: Combustive Microbicidal Action and Chemiluminescence

    PubMed Central

    Allen, Robert C.

    2015-01-01

    Neutrophil leukocytes protect against a varied and complex array of microbes by providing microbicidal action that is simple, potent, and focused. Neutrophils provide such action via redox reactions that change the frontier orbitals of oxygen (O2) facilitating combustion. The spin conservation rules define the symmetry barrier that prevents direct reaction of diradical O2 with nonradical molecules, explaining why combustion is not spontaneous. In burning, the spin barrier is overcome when energy causes homolytic bond cleavage producing radicals capable of reacting with diradical O2 to yield oxygenated radical products that further participate in reactive propagation. Neutrophil mediated combustion is by a different pathway. Changing the spin quantum state of O2 removes the symmetry restriction to reaction. Electronically excited singlet molecular oxygen (1O2*) is a potent electrophilic reactant with a finite lifetime that restricts its radius of reactivity and focuses combustive action on the target microbe. The resulting exergonic dioxygenation reactions produce electronically excited carbonyls that relax by light emission, that is, chemiluminescence. This overview of neutrophil combustive microbicidal action takes the perspectives of spin conservation and bosonic-fermionic frontier orbital considerations. The necessary principles of particle physics and quantum mechanics are developed and integrated into a fundamental explanation of neutrophil microbicidal metabolism. PMID:26783542

  15. Production of monoclonal antibodies against canine leukocytes.

    PubMed

    Aguiar, Paulo Henrique Palis; Borges dos Santos, Roberto Robson; Lima, Carla Andrade; Rios de Sousa Gomes, Hilton; Larangeira, Daniela Farias; Santos, Patrícia Meira; Barrouin-Melo, Stella Maria; Conrado dos-Santos, Washington Luis; Pontes-de-Carvalho, Lain

    2004-04-01

    A panel of anti-canine leukocyte monoclonal antibodies (MAbs) was produced by immunizing BALB/c mice with canine peripheral blood mononuclear cells (PBMC), either resting or stimulated with concanavalin A (ConA). Three out of 28 clones-IH1, AB6, and HG6-screened by ELISA and producing antibody with the highest specificity for canine cell immunostaining, were subjected to three subsequent subcloning steps by limiting dilution, and selected for further characterization. These MAbs belonged to IgG1 (HG6 and IH1) and IgG2a (AB6) isotypes. The distribution of cell populations expressing the antigen recognized by the antibodies was identified by indirect immunoflorescence on canine PBMC and on tissue sections of lymph node, spleen, liver and skin. The possible crossreactivity with human PBMC was also examined in immunocytochemistry. One of the antibodies specifically recognized macrophages. The MAbs presented here can be foreseen as possible valuable diagnostic and research tools to study immune functions in dogs. PMID:15165486

  16. Isolation of Leukocytes from the Human Maternal-fetal Interface.

    PubMed

    Xu, Yi; Plazyo, Olesya; Romero, Roberto; Hassan, Sonia S; Gomez-Lopez, Nardhy

    2015-01-01

    Pregnancy is characterized by the infiltration of leukocytes in the reproductive tissues and at the maternal-fetal interface (decidua basalis and decidua parietalis). This interface is the anatomical site of contact between maternal and fetal tissues; therefore, it is an immunological site of action during pregnancy. Infiltrating leukocytes at the maternal-fetal interface play a central role in implantation, pregnancy maintenance, and timing of delivery. Therefore, phenotypic and functional characterizations of these leukocytes will provide insight into the mechanisms that lead to pregnancy disorders. Several protocols have been described in order to isolate infiltrating leukocytes from the decidua basalis and decidua parietalis; however, the lack of consistency in the reagents, enzymes, and times of incubation makes it difficult to compare these results. Described herein is a novel approach that combines the use of gentle mechanical and enzymatic dissociation techniques to preserve the viability and integrity of extracellular and intracellular markers in leukocytes isolated from the human tissues at the maternal-fetal interface. Aside from immunophenotyping, cell culture, and cell sorting, the future applications of this protocol are numerous and varied. Following this protocol, the isolated leukocytes can be used to determine DNA methylation, expression of target genes, in vitro leukocyte functionality (i.e., phagocytosis, cytotoxicity, T-cell proliferation, and plasticity, etc.), and the production of reactive oxygen species at the maternal-fetal interface. Additionally, using the described protocol, this laboratory has been able to describe new and rare leukocytes at the maternal-fetal interface. PMID:26067211

  17. Track geometry estimation from car-body vibration

    NASA Astrophysics Data System (ADS)

    Tsunashima, Hitoshi; Naganuma, Yasukuni; Kobayashi, Takahito

    2014-05-01

    Track maintenance works based on track geometry recordings are essential to enhance the safety and comfort of railway transportation. The track condition monitoring system is mainly used for the choice of area needing track tamping works for the purpose of the good riding comfort. An advantage of car-body acceleration measurement devices is their simple structures, which make it easier to carry out maintenance. However, the car-body acceleration waveform is considerably different from track geometry. This paper demonstrates the possibility to estimate the track geometry of Shinkansen tracks using car-body motions only. In an inverse problem to estimate track irregularity from car-body motions, a Kalman Filter (KF) was applied to solve the problem. Estimation results showed that track irregularity estimation in vertical direction is possible with acceptable accuracy for real use.

  18. CD99 is essential for leukocyte diapedesis in vivo.

    PubMed

    Dufour, Eric M; Deroche, Alana; Bae, Youngmee; Muller, William A

    2008-11-01

    Recruitment of leukocytes into inflamed tissue requires migration of leukocytes from the blood stream across the endothelial lining and the basement membrane of the local blood vessels. CD99 in humans is a 32-kDa highly O-glycosylated cell surface protein expressed on most leukocytes. The authors recently found CD99 to be expressed in leukocytes and at human endothelial cell contacts. Human CD99 is involved in homophilic interaction between the two cell types and participates in the transendothelial migration of monocytes and polymorphonuclear neutrophils (PMNs) in vitro. To test the role of CD99 in vivo, the authors cloned murine CD99 (muCD99), expressed it in vitro, and generated a blocking monoclonal antibody against it. We first showed that muCD99 is expressed on mouse leukocytes as well as enriched at the endothelial cell borders. Transfection of cells with muCD99 imparts on them the ability to aggregate in a CD99-dependent homophilic manner. Cells expressing muCD99 did not bind to cells expressing murine or human platelet endothelial call adhesion molecule (PECAM) or human CD99. In the thioglycollate peritonitis model of inflammation, anti-CD99 monoclonal antibody blocked the recruitment of neutrophils and monocytes by over 40% and 80%, respectively, at 18 h. Microscopy showed that this blocking occurred at the luminal surface of venules. The authors conclude that CD99 plays a major role in the emigration of leukocytes in vivo. PMID:18923973

  19. Binding of Pasteurella haemolytica leukotoxin to bovine leukocytes.

    PubMed Central

    Brown, J F; Leite, F; Czuprynski, C J

    1997-01-01

    Pasteurella haemolytica is the principal bacterial pathogen in the bovine respiratory disease complex. This organism produces an exotoxin (referred to as leukotoxin) during logarithmic-phase growth that is a potent leukocyte-modulating agent. At low concentrations, it activates neutrophils and mononuclear phagocytes to release inflammatory mediators, while at the same time making these cells destined to undergo apoptotic cell death. At higher concentrations, the toxin causes rapid swelling and loss of cell viability. In this study, we demonstrated that toxin binding can be directly evaluated by flow cytometry with biologically active biotinylated leukotoxin. Leukotoxin binding was blocked by the addition of a neutralizing anti-leukotoxin monoclonal antibody and was not detected when bovine leukocytes were incubated with culture filtrates from a mutant strain of P. haemolytica that does not produce biologically active leukotoxin. In addition, treatment of bovine leukocytes with protease K eliminated subsequent binding of leukotoxin, suggesting that there is a protein on the leukocyte surface that is either a leukotoxin binding site or is required for stabilization of leukotoxin binding. We did not detect binding of biotinylated leukotoxin to porcine or human leukocytes, which have been reported previously to be resistant to the lytic effects of the leukotoxin. These findings suggest that there may be a specific binding site for P. haemolytica leukotoxin on bovine but not on porcine or human leukocytes and that it might be involved in the activation and lytic activities of the leukotoxin. PMID:9284143

  20. Airway distension promotes leukocyte recruitment in rat tracheal circulation.

    PubMed

    Lim, Lina H K; Wagner, Elizabeth M

    2003-11-01

    Mechanical distortion of blood vessels is known to activate endothelial cells. Whether airway distension likewise activates the vascular endothelium within the airway wall is unknown. Using intravital microscopy in the rat trachea, we investigated if airway distention with the application of positive end-expiratory pressure (PEEP) caused leukocyte recruitment to the airway. Tracheal postcapillary venules were visualized and leukocyte kinetics monitored in anesthetized, mechanically ventilated rats (80 breaths/minute, 6 ml/kg VT, 1 cm H(2)O PEEP). Leukocyte rolling velocity (Vwbc) and the number of adherent cells were not altered with normal ventilation over the course of 2 hours. Ventilation with sustained PEEP (8 cm H(2)O for 1 hour reduced Vwbc and increased adhesion, reaching a maximum at 1 hour of PEEP. Intermittent (2x and 5x) 8 cm H(2)O PEEP also induced a similar reduction in Vwbc, accompanied by an increase in adhesion. However, leukocyte recruitment after airway distension is localized to the airways because increased PEEP did not induce leukocyte recruitment in the mesenteric microcirculation or when PEEP was applied to the lung distal to the site of measurement. Pretreatment with endothelin receptor and selectin inhibitors blocked the effects of distension on leukocyte recruitment, suggesting their involvement in the proinflammatory response. PMID:12869357

  1. Physiological levels of testosterone kill salmonid leukocytes in vitro

    USGS Publications Warehouse

    Slater, C.H.; Schreck, C.B.

    1997-01-01

    Adult spring chinook salmon (Oncorhynchus tshawytscha) elaborate high plasma concentrations of testosterone during sexual maturation, and these levels of testosterone have been shown to reduce the salmonid immune response in vitro. Our search for the mechanism of testosterone's immunosuppressive action has led to the characterization of an androgen receptor in salmonid leukocytes. In the present study we examined the specific effects that testosterone had on salmonid leukocytes. Direct counts of viable leukocytes after incubation with and without physiological levels of testosterone demonstrate a significant loss of leukocytes in cultures exposed to testosterone. At least 5 days of contact with testosterone was required to produce significant immunosuppression and addition of a 'conditioned media' (supernatant from proliferating lymphocytes not exposed to testosterone) did not reverse the immunosuppressive effects of testosterone. These data lead us to conclude that testosterone may exert its immunosuppressive effects by direct action on salmonid leukocytes, through the androgen receptor described, and that this action leads to the death of a significant number of these leukocytes.

  2. C-type natriuretic peptide inhibits leukocyte recruitment and platelet-leukocyte interactions via suppression of P-selectin expression

    PubMed Central

    Scotland, Ramona S.; Cohen, Marc; Foster, Paul; Lovell, Matthew; Mathur, Anthony; Ahluwalia, Amrita; Hobbs, Adrian J.

    2005-01-01

    The multifaceted process of immune cell recruitment to sites of tissue injury is key to the development of an inflammatory response and involved in the pathogenesis of numerous cardiovascular disorders. We recently identified C-type natriuretic peptide (CNP) as an important endothelium-derived mediator that regulates vascular tone and protects against myocardial ischemia/reperfusion injury. Herein, we investigated whether CNP inhibits leukocyte recruitment and platelet aggregation and thereby exerts a potential antiinflammatory influence on the blood vessel wall. We assessed the effects of CNP on leukocyte-endothelial cell interactions in mouse mesenteric postcapillary venules in vivo in animals with high basal leukocyte activation (endothelial nitric oxide synthase knockout mice, eNOS-/-) or under acute inflammatory conditions (induced by interleukin-1β or histamine). CNP suppressed basal leukocyte rolling in eNOS-/- mice in a rapid, reversible, and concentration-dependent manner. These effects of CNP were mimicked by the selective natriuretic peptide receptor-C agonist cANF4-23. CNP also suppressed leukocyte rolling induced by IL-1β or histamine, inhibited platelet-leukocyte interactions, and prevented thrombin-induced platelet aggregation of human blood. Furthermore, analysis of human umbilical vein endothelial cells, leukocytes, and platelets revealed that CNP selectively attenuates expression of P-selectin. Thus, CNP is a modulator of acute inflammation in the blood vessel wall characterized by leukocyte and platelet activation. These antiinflammatory effects appear to be mediated, at least in part, via suppression of P-selectin expression. These observations suggest that endothelial CNP might maintain an anti-atherogenic influence on the blood vessel wall and represent a target for therapeutic intervention in inflammatory cardiovascular disorders. PMID:16179391

  3. C-type natriuretic peptide inhibits leukocyte recruitment and platelet-leukocyte interactions via suppression of P-selectin expression

    NASA Astrophysics Data System (ADS)

    Scotland, Ramona S.; Cohen, Marc; Foster, Paul; Lovell, Matthew; Mathur, Anthony; Ahluwalia, Amrita; Hobbs, Adrian J.

    2005-10-01

    The multifaceted process of immune cell recruitment to sites of tissue injury is key to the development of an inflammatory response and involved in the pathogenesis of numerous cardiovascular disorders. We recently identified C-type natriuretic peptide (CNP) as an important endothelium-derived mediator that regulates vascular tone and protects against myocardial ischemia/reperfusion injury. Herein, we investigated whether CNP inhibits leukocyte recruitment and platelet aggregation and thereby exerts a potential antiinflammatory influence on the blood vessel wall. We assessed the effects of CNP on leukocyte-endothelial cell interactions in mouse mesenteric postcapillary venules in vivo in animals with high basal leukocyte activation (endothelial nitric oxide synthase knockout mice, eNOS-/-) or under acute inflammatory conditions (induced by interleukin-1 or histamine). CNP suppressed basal leukocyte rolling in eNOS-/- mice in a rapid, reversible, and concentration-dependent manner. These effects of CNP were mimicked by the selective natriuretic peptide receptor-C agonist cANF4-23. CNP also suppressed leukocyte rolling induced by IL-1 or histamine, inhibited platelet-leukocyte interactions, and prevented thrombin-induced platelet aggregation of human blood. Furthermore, analysis of human umbilical vein endothelial cells, leukocytes, and platelets revealed that CNP selectively attenuates expression of P-selectin. Thus, CNP is a modulator of acute inflammation in the blood vessel wall characterized by leukocyte and platelet activation. These antiinflammatory effects appear to be mediated, at least in part, via suppression of P-selectin expression. These observations suggest that endothelial CNP might maintain an anti-atherogenic influence on the blood vessel wall and represent a target for therapeutic intervention in inflammatory cardiovascular disorders. endothelium | natriuretic peptide receptor type C | atherosclerosis | thrombosis

  4. Insulin radioreceptor assay on murine splenic leukocytes and peripheral erythrocytes

    SciTech Connect

    Shimizu, F.; Kahn, R.

    1982-02-01

    Insulin radioreceptor assays were developed using splenic leukocytes and peripheral erythrocytes from individual mice. Splenic leukocytes were prepared using an NH/sub 4/Cl buffer which did not alter insulin binding, but gave much higher yields than density gradient methods. Mouse erythrocytes were isolated from heparinized blood by three passages over a Boyum gradient, and a similar buffer was used to separate cells from free (/sup 125/I)iodoinsulin at the end of the binding incubation. Insulin binding to both splenic leukocytes and peripheral erythrocytes had typical pH, temperature, and time dependencies, and increased linearly with an increased number of cells. Optimal conditions for the splenic leukocytes (6 x 10/sup 7//ml) consisted of incubation with (/sup 125/I)iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.0. In cells from 20 individual mice, the specific (/sup 125/I)iodoinsulin binding was 2.6 +/- 0.1% (SEM), and nonspecific binding was 0.3 +/- 0.04% (10.6% of total binding). Erythrocytes (2.8 x 10/sup 9//ml) were incubated with (/sup 125/)iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.2. In cells from 25 individual mice, the specific (/sup 125/I)iodoinsulin binding was 4.5 +/- 0.2%, and nonspecific binding was 0.7 +/- 0.03% (13.6% of total binding). In both splenic leukocytes and peripheral erythrocytes, analysis of equilibrium binding data produced curvilinear Scatchard plots with approximately 3500 binding sites/leukocyte and 20 binding sites/erythrocyte. These data demonstrate that adequate numbers of splenic leukocytes and peripheral erythrocytes can be obtained from individual mice to study insulin binding in a precise and reproducible manner.

  5. Crossing the Vascular Wall: Common and Unique Mechanisms Exploited by Different Leukocyte Subsets during Extravasation

    PubMed Central

    Schnoor, Michael; Alcaide, Pilar; Voisin, Mathieu-Benoit; van Buul, Jaap D.

    2015-01-01

    Leukocyte extravasation is one of the essential and first steps during the initiation of inflammation. Therefore, a better understanding of the key molecules that regulate this process may help to develop novel therapeutics for treatment of inflammation-based diseases such as atherosclerosis or rheumatoid arthritis. The endothelial adhesion molecules ICAM-1 and VCAM-1 are known as the central mediators of leukocyte adhesion to and transmigration across the endothelium. Engagement of these molecules by their leukocyte integrin receptors initiates the activation of several signaling pathways within both leukocytes and endothelium. Several of such events have been described to occur during transendothelial migration of all leukocyte subsets, whereas other mechanisms are known only for a single leukocyte subset. Here, we summarize current knowledge on regulatory mechanisms of leukocyte extravasation from a leukocyte and endothelial point of view, respectively. Specifically, we will focus on highlighting common and unique mechanisms that specific leukocyte subsets exploit to succeed in crossing endothelial monolayers. PMID:26568666

  6. Extravasation of leukocytes in comparison to tumor cells

    PubMed Central

    Strell, Carina; Entschladen, Frank

    2008-01-01

    The multi-step process of the emigration of cells from the blood stream through the vascular endothelium into the tissue has been termed extravasation. The extravasation of leukocytes is fairly well characterized down to the molecular level, and has been reviewed in several aspects. Comparatively little is known about the extravasation of tumor cells, which is part of the hematogenic metastasis formation. Although the steps of the process are basically the same in leukocytes and tumor cells, i.e. rolling, adhesion, transmigration (diapedesis), the molecules that are involved are different. A further important difference is that leukocyte interaction with the endothelium changes the endothelial integrity only temporarily, whereas tumor cell interaction leads to an irreversible damage of the endothelial architecture. Moreover, tumor cells utilize leukocytes for their extravasation as linkers to the endothelium. Thus, metastasis formation is indirectly susceptible to localization signals that are literally specific for the immune system. We herein compare the extravasation of leukocytes and tumor cells with regard to the involved receptors and the localization signals that direct the cells to certain organs and sites of the body. PMID:19055814

  7. Platelets Guide Leukocytes to Their Sites of Extravasation

    PubMed Central

    Puhr-Westerheide, Daniel; Pörnbacher, Michaela; Lauber, Kirsten; Krombach, Fritz; Reichel, Christoph Andreas

    2016-01-01

    Effective immune responses require the directed migration of leukocytes from the vasculature to the site of injury or infection. How immune cells “find” their site of extravasation remains largely obscure. Here, we identified a previously unrecognized role of platelets as pathfinders guiding leukocytes to their exit points in the microvasculature: upon onset of inflammation, circulating platelets were found to immediately adhere at distinct sites in venular microvessels enabling these cellular blood components to capture neutrophils and, in turn, inflammatory monocytes via CD40-CD40L-dependent interactions. In this cellular crosstalk, ligation of PSGL-1 by P-selectin leads to ERK1/2 MAPK-dependent conformational changes of leukocyte integrins, which promote the successive extravasation of neutrophils and monocytes to the perivascular tissue. Conversely, blockade of this cellular partnership resulted in misguided, inefficient leukocyte responses. Our experimental data uncover a platelet-directed, spatiotemporally organized, multicellular crosstalk that is essential for effective trafficking of leukocytes to the site of inflammation. PMID:27152726

  8. Recent insights into endothelial control of leukocyte extravasation.

    PubMed

    Hordijk, Peter L

    2016-04-01

    In the process of leukocyte migration from the circulation across the vascular wall, the crosstalk with endothelial cells that line the blood vessels is essential. It is now firmly established that in endothelial cells important signaling events are initiated upon leukocyte adhesion that impinge on the regulation of cell-cell contact and control the efficiency of transendothelial migration. In addition, several external factors such as shear force and vascular stiffness were recently identified as important regulators of endothelial signaling and, consequently, leukocyte transmigration. Here, I review recent insights into endothelial signaling events that are linked to leukocyte migration across the vessel wall. In this field, protein phosphorylation and Rho-mediated cytoskeletal dynamics are still widely studied using increasingly sophisticated mouse models. In addition, activation of tyrosine phosphatases, changes in endothelial cell stiffness as well as different vascular beds have all been established as important factors in endothelial signaling and leukocyte transmigration. Finally, I address less-well-studied but interesting components in the endothelium that also control transendothelial migration, such as the ephrins and their Eph receptors, that provide novel insights in the complexity associated with this process. PMID:26794844

  9. Doppler tracking

    NASA Astrophysics Data System (ADS)

    Thomas, Christopher Jacob

    This study addresses the development of a methodology using the Doppler Effect for high-resolution, short-range tracking of small projectiles and vehicles. Minimal impact on the design of the moving object is achieved by incorporating only a transmitter in it and using ground stations for all other components. This is particularly useful for tracking objects such as sports balls that have configurations and materials that are not conducive to housing onboard instrumentation. The methodology developed here uses four or more receivers to monitor a constant frequency signal emitted by the object. Efficient and accurate schemes for filtering the raw signals, determining the instantaneous frequencies, time synching the frequencies from each receiver, smoothing the synced frequencies, determining the relative velocity and radius of the object and solving the nonlinear system of equations for object position in three dimensions as a function of time are developed and described here.

  10. 49 CFR 213.345 - Vehicle/track system qualification.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the wheel/rail force safety limits and the carbody and truck acceleration criteria specified in § 213... representative of the route. (3) Carbody acceleration. For vehicle types intended to operate at track Class 6... not exceed the carbody lateral and vertical acceleration safety limits specified in § 213.333....

  11. 49 CFR 213.345 - Vehicle/track system qualification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the wheel/rail force safety limits and the carbody and truck acceleration criteria specified in § 213... representative of the route. (3) Carbody acceleration. For vehicle types intended to operate at track Class 6... not exceed the carbody lateral and vertical acceleration safety limits specified in § 213.333....

  12. [Case presentation: bovine leukocyte adhesion deficiency (BLAD) in Switzerland].

    PubMed

    Meylan, M; Abegg, R; Sager, H; Jungi, T W; Martig, J

    1997-01-01

    Bovine Leukocyte Adhesion Deficiency (BLAD) Syndrome is a lethal congenital immunodeficiency caused by the strong reduction in the expression of leukocyte integrins (beta 2 integrins) on the surface of leukocytes. Therefore, neutrophils from BLAD animals lack the capacity to adhere to the endothelium, a necessary step in their emigration into foci of infection. Due to the virtual absence of neutrophil-mediated host defense, animals suffer from recurrent infection of the respiratory and gastrointestinal tracts and finally succumb to infections. A 14 days old Holstein-Friesian calf showing omphalophlebitis and leukocytosis, was referred to our clinic. It was found to suffer from several febrile episodes of infection. The tentative diagnosis BLAD could be confirmed for the first time in Switzerland by flow cytometry, pedigree analysis and by restriction fragment length polymorphism. PMID:9411734

  13. Manipulating leukocyte interactions in vivo through optogenetic chemokine release.

    PubMed

    Sarris, Milka; Olekhnovitch, Romain; Bousso, Philippe

    2016-06-01

    Light-mediated release of signaling ligands, such as chemoattractants, growth factors, and cytokines is an attractive strategy for investigation and therapeutic targeting of leukocyte communication and immune responses. We introduce a versatile optogenetic method to control ligand secretion, combining UV-conditioned endoplasmic reticulum-to-Golgi trafficking and a furin-processing step. As proof of principle, we achieved light-triggered chemokine secretion and demonstrated that a brief pulse of chemokine release can mediate a rapid flux of leukocyte contacts with target cells in vitro and in vivo. This approach opens new possibilities for dynamic investigation of leukocyte communication in vivo and may confer the potential to control the local release of soluble mediators in the context of immune cell therapies. PMID:27057000

  14. Improving diagnosis of appendicitis. Early autologous leukocyte scanning

    SciTech Connect

    DeLaney, A.R.; Raviola, C.A.; Weber, P.N.; McDonald, P.T.; Navarro, D.A.; Jasko, I. )

    1989-10-01

    A prospective nonrandomized study investigating the accuracy and utility of autologous leukocyte scanning in the diagnosis of appendicitis was performed. One hundred patients in whom the clinical diagnosis of appendicitis was uncertain underwent indium 111 oxyquinoline labelling of autologous leukocytes and underwent scanning 2 hours following reinjection. Of 32 patients with proved appendicitis, three scans revealed normal results (false-negative rate, 0.09). Of 68 patients without appendicitis, three scans had positive results (false-positive rate, 0.03; sensitivity, 0.91; specificity, 0.97; predictive value of positive scan, 0.94; predictive value of negative scan, 0.96; and overall accuracy, 0.95). Scan results altered clinical decisions in 19 patients. In 13 cases, the scan produced images consistent with diagnoses other than appendicitis, expediting appropriate management. Early-imaging In 111 oxyquinoline autologous leukocyte scanning is a practical and highly accurate adjunct for diagnosing appendicitis.

  15. Apoptosis-promoted tumorigenesis: gamma-irradiation-induced thymic lymphomagenesis requires Puma-driven leukocyte death.

    PubMed

    Michalak, Ewa M; Vandenberg, Cassandra J; Delbridge, Alex R D; Wu, Li; Scott, Clare L; Adams, Jerry M; Strasser, Andreas

    2010-08-01

    Although tumor development requires impaired apoptosis, we describe a novel paradigm of apoptosis-dependent tumorigenesis. Because DNA damage triggers apoptosis through p53-mediated induction of BH3-only proteins Puma and Noxa, we explored their roles in gamma-radiation-induced thymic lymphomagenesis. Surprisingly, whereas Noxa loss accelerated it, Puma loss ablated tumorigenesis. Tumor suppression by Puma deficiency reflected its protection of leukocytes from gamma-irradiation-induced death, because their glucocorticoid-mediated decimation in Puma-deficient mice activated cycling of stem/progenitor cells and restored thymic lymphomagenesis. Our demonstration that cycles of cell attrition and repopulation by stem/progenitor cells can drive tumorigenesis has parallels in human cancers, such as therapy-induced malignancies. PMID:20679396

  16. Upregulation of Leukocytic Syncytin-1 in Acute Myeloid Leukemia Patients.

    PubMed

    Sun, Yi; Zhu, Hongyan; Song, Jianxin; Jiang, Yaxian; Ouyang, Hongmei; Huang, Rongzhong; Zhang, Guiqian; Fan, Xin; Tao, Rui; Jiang, Jie; Niu, Hua

    2016-01-01

    BACKGROUND Syncytin-1, a cell membrane-localizing fusogen, is abnormally expressed in several cancers, including endometrial cancer, breast cancer, and leukemia. Although abnormal syncytin-1 expression has been detected in two-thirds of leukemia blood samples, its expression profile in acute leukemia patients has not yet been analyzed. MATERIAL AND METHODS Bone marrow samples from 50 acute myelogenous leukemia (AML) cases and 14 B-cell acute lymphocytic leukemia (B-cell ALL) patients were subjected to flow cytometry to assess leukocyte type distributions and leukocytic syncytin-1 surface expression. RT-PCR was applied to assess leukocytic syncytin-1 mRNA expression. Statistical analysis was applied to compare syncytin-1 expression between AML and B-cell ALL patients across blasts, granulocytes, lymphocytes, and monocytes as well as to determine clinical factors statistically associated with changes in syncytin-1 expression. RESULTS The leukocyte type distributions of the AML and B-cell ALL cohorts highly overlapped, with an observable difference in blast distribution between the 2 cohorts. The AML cohort displayed significantly greater syncytin-1 surface and mRNA expression (p<0.05). Syncytin-1 surface and mRNA expression was significantly increased across all 4 leukocyte types (p<0.05). The percentage of syncytin-1-expressing blasts was significantly greater in AML patients (p<0.05), with blasts showing the largest fold-change in syncytin-1 expression (p<0.05). M5, M5a, and M5b AML patients displayed significantly higher syncytin-1 surface expression relative to all other AML French-American-British (FAB) classifications (p<0.05). CONCLUSIONS These findings suggest leukocytic syncytin-1 expression may play a role in the development and/or maintenance of the AML phenotype and the acute monocytic leukemia phenotype in particular. PMID:27393911

  17. Upregulation of Leukocytic Syncytin-1 in Acute Myeloid Leukemia Patients

    PubMed Central

    Sun, Yi; Zhu, Hongyan; Song, Jianxin; Jiang, Yaxian; Ouyang, Hongmei; Huang, Rongzhong; Zhang, Guiqian; Fan, Xin; Tao, Rui; Jiang, Jie; Niu, Hua

    2016-01-01

    Background Syncytin-1, a cell membrane-localizing fusogen, is abnormally expressed in several cancers, including endometrial cancer, breast cancer, and leukemia. Although abnormal syncytin-1 expression has been detected in two-thirds of leukemia blood samples, its expression profile in acute leukemia patients has not yet been analyzed. Material/Methods Bone marrow samples from 50 acute myelogenous leukemia (AML) cases and 14 B-cell acute lymphocytic leukemia (B-cell ALL) patients were subjected to flow cytometry to assess leukocyte type distributions and leukocytic syncytin-1 surface expression. RT-PCR was applied to assess leukocytic syncytin-1 mRNA expression. Statistical analysis was applied to compare syncytin-1 expression between AML and B-cell ALL patients across blasts, granulocytes, lymphocytes, and monocytes as well as to determine clinical factors statistically associated with changes in syncytin-1 expression. Results The leukocyte type distributions of the AML and B-cell ALL cohorts highly overlapped, with an observable difference in blast distribution between the 2 cohorts. The AML cohort displayed significantly greater syncytin-1 surface and mRNA expression (p<0.05). Syncytin-1 surface and mRNA expression was significantly increased across all 4 leukocyte types (p<0.05). The percentage of syncytin-1-expressing blasts was significantly greater in AML patients (p<0.05), with blasts showing the largest fold-change in syncytin-1 expression (p<0.05). M5, M5a, and M5b AML patients displayed significantly higher syncytin-1 surface expression relative to all other AML French-American-British (FAB) classifications (p<0.05). Conclusions These findings suggest leukocytic syncytin-1 expression may play a role in the development and/or maintenance of the AML phenotype and the acute monocytic leukemia phenotype in particular. PMID:27393911

  18. Leukocyte segmentation and classification in blood-smear images.

    PubMed

    Ramoser, Herbert; Laurain, Vincent; Bischof, Horst; Ecker, Rupert

    2005-01-01

    The detection and classification of leukocytes in blood smear images is a routine task in medical diagnosis. In this paper we present a fully automated approach to leukocyte segmentation that is robust with respect to cell appearance and image quality. A set of features is used to describe cytoplasm and nucleus properties. Pairwise SVM classification is used to discriminate between different cell types. Evaluation on a set of 1166 images (13 classes) resulted in 95% correct segmentations and 75% to 99% correct classification (with reject option). PMID:17280945

  19. Detection of deep venous thrombosis by indium-111 leukocyte scintigraphy

    SciTech Connect

    D'Alonzo, W.A. Jr.; Alavi, A.

    1986-05-01

    Indium-111-labeled leukocyte ((/sup 111/In)WBC) scintigraphy has been used successfully for detection of inflammation. Occasionally, noninflammatory collections of white blood cells such as hematomas or hemorrhage have been localized. We report a case in which unsuspected femoral deep venous thrombosis was diagnosed on an (/sup 111/In)WBC leukocyte scan performed for detection of osteomyelitis. Readers are advised to avoid interpreting all vascular (/sup 111/In)WBC localization as necessarily infectious. This may be of particular significance in patients with vascular grafts.

  20. Therapeutic hypothermia impacts leukocyte kinetics after cardiac arrest

    PubMed Central

    Dufner, Matthias C.; Andre, Florian; Stiepak, Jan; Zelniker, Thomas; Chorianopoulos, Emmanuel; Preusch, Michael; Katus, Hugo A.

    2016-01-01

    Background Patients admitted to the hospital after primarily successful cardiopulmonary resuscitation (CPR) are at a very high risk for neurologic deficits and death. Targeted temperature management (TTM) for mild therapeutic hypothermia has been shown to improve survival compared to standard treatment. Acute cardiovascular events, such as myocardial infarction (MI), are a major cause for cardiac arrest (CA) in patients who undergo CPR. Recent findings have demonstrated the importance and impact of the leukocyte response following acute MI. Methods In this retrospective, single center study we enrolled 169 patients with CA due to non-traumatic causes and primarily successful CPR. A total of 111 subjects (66%) underwent TTM aiming for a target temperature of 32–34 °C. Results Analysis of 30 day follow up showed a significantly improved survival of all patients who received TTM compared to patients without hypothermia (P=0.0001). Furthermore TTM was an independent variable of good neurological outcome after 6 months (P=0.0030). Therapeutic hypothermia was found to be beneficial independent of differences in age and sex between both groups. While a higher rate of pneumonia was observed with TTM, this diagnosis had no additional impact on survival or neurological outcome. The beneficial effect on mortality remained significant in patients with the diagnosis of an acute cardiac event (P=0.0145). Next, we evaluated the kinetics of leukocytes in this group over the course of 7 days after CA. At presentation, patients showed a mean level of 16.5±6.7 of leukocytes per microliter. While this level stayed stable in the group of patients without hypothermia, patients who received TTM showed a significant decline of leukocyte levels resulting in significantly lower numbers of leukocytes on days 3 and 5 after CPR. Interestingly, these differences in leukocyte counts remained beyond the time period of TTM while C-reactive protein (CRP) levels were suppressed only during

  1. Accelerated Reader.

    ERIC Educational Resources Information Center

    Education Commission of the States, Denver, CO.

    This paper provides an overview of Accelerated Reader, a system of computerized testing and record-keeping that supplements the regular classroom reading program. Accelerated Reader's primary goal is to increase literature-based reading practice. The program offers a computer-aided reading comprehension and management program intended to motivate…

  2. The Effect of Hemiscorpius lepturus (Scorpionida: Hemiscorpiidae) Venom on Leukocytes and the Leukocyte Subgroups in Peripheral Blood of Rat

    PubMed Central

    Ghafourian, Mehri; Ganjalikhanhakemi, Neda; Hemmati, Ali Asghar; Dehghani, Rouhullah; Kooti, Wesam

    2016-01-01

    Background: The aim of this study was to investigate the effect of Hemiscorpius lepturus venom on leukocytes and the leukocyte subgroups in peripheral blood of rat. Methods: In this experimental study, sixty N-Mari rats were divided into three groups of 20 rats. Then the rats in each group were divided into four subgroups based on the blood sampling time that was 2, 6, 24 and 48 hours after the venom injection, respectively. The control group did not receive anything, however, the first and the second experimental groups received 0.1 and 0.01mg/kg of venom, subcutaneously. In accordance with a designated four sampling times, the blood sampling was carried out in three groups. After RBC lysis, the leukocytes and leukocyte sub-populations were determined and counted using appropriate hematological standard methods. Results: The leukocyte and the neutrophil count at two (P<0.05), six (P<0.01) and 24 (P<0.05) hours after the venom injection showed a significant decline compared with the control group, this decrease was significant at the dose of 0.1 mg/kg until 48 hours after the venom injection (P<0.05). The lymphocyte count showed a significant decline throughout the all hours of the experiment, compared with the control group (P<0.05). Conclusion: Leukocytes are probably affected by the cytotoxicity effect of the H. lepturus venom in a dose-dependent manner. This could be a wakeup call for the medical staff to perform quick and accurate treatment in the least time possible. PMID:27308274

  3. Kalman Orbit Optimized Loop Tracking

    NASA Technical Reports Server (NTRS)

    Young, Lawrence E.; Meehan, Thomas K.

    2011-01-01

    Under certain conditions of low signal power and/or high noise, there is insufficient signal to noise ratio (SNR) to close tracking loops with individual signals on orbiting Global Navigation Satellite System (GNSS) receivers. In addition, the processing power available from flight computers is not great enough to implement a conventional ultra-tight coupling tracking loop. This work provides a method to track GNSS signals at very low SNR without the penalty of requiring very high processor throughput to calculate the loop parameters. The Kalman Orbit-Optimized Loop (KOOL) tracking approach constitutes a filter with a dynamic model and using the aggregate of information from all tracked GNSS signals to close the tracking loop for each signal. For applications where there is not a good dynamic model, such as very low orbits where atmospheric drag models may not be adequate to achieve the required accuracy, aiding from an IMU (inertial measurement unit) or other sensor will be added. The KOOL approach is based on research JPL has done to allow signal recovery from weak and scintillating signals observed during the use of GPS signals for limb sounding of the Earth s atmosphere. That approach uses the onboard PVT (position, velocity, time) solution to generate predictions for the range, range rate, and acceleration of the low-SNR signal. The low- SNR signal data are captured by a directed open loop. KOOL builds on the previous open loop tracking by including feedback and observable generation from the weak-signal channels so that the MSR receiver will continue to track and provide PVT, range, and Doppler data, even when all channels have low SNR.

  4. Magnetic Launch Assist Experimental Track

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In this photograph, a futuristic spacecraft model sits atop a carrier on the Magnetic Launch Assist System, formerly known as the Magnetic Levitation (MagLev) System, experimental track at the Marshall Space Flight Center (MSFC). Engineers at MSFC have developed and tested Magnetic Launch Assist technologies that would use magnetic fields to levitate and accelerate a vehicle along a track at very high speeds. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, a Magnetic Launch Assist system would electromagnetically drive a space vehicle along the track. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. This track is an advanced linear induction motor. Induction motors are common in fans, power drills, and sewing machines. Instead of spinning in a circular motion to turn a shaft or gears, a linear induction motor produces thrust in a straight line. Mounted on concrete pedestals, the track is 100-feet long, about 2-feet wide, and about 1.5-feet high. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

  5. Studies on gonococcus infection. XV. Identification of surface proteins of Neisseria gonorrhoeae correlated with leukocyte association.

    PubMed Central

    King, G J; Swanson, J

    1978-01-01

    Neisseria gonorrhoeae which exhibit high levels of leukocyte association have a surface protein which is considerably diminished in isogenic gonococci which exhibit low levels of leukocyte association (LA). The LA protein exhibits strain variation in molecular weight and immunogenicity. Membranes derived from LA+ and LA- organisms show quantitative differences in their adsorption to leukocytes; these differences are analogous to those found for the intact organisms regarding their association with leukocytes. Images PMID:211086

  6. Leukocyte driven-decidual angiogenesis in early pregnancy.

    PubMed

    Lima, Patricia D A; Zhang, Jianhong; Dunk, Caroline; Lye, Stephen J; Croy, B Anne

    2014-11-01

    Successful pregnancy and long-term, post-natal maternal and offspring cardiac, vascular and metabolic health require key maternal cardiovascular adaptations over gestation. Within the pregnant decidualizing uterus, coordinated vascular, immunological and stromal cell changes occur. Considerable attention has been given to the roles of uterine natural killer (uNK) cells in initiating decidual spiral arterial remodeling, a process normally completed by mid-gestation in mice and in humans. However, leukocyte roles in much earlier, region specific, decidual vascular remodeling are now being defined. Interest in immune cell-promoted vascular remodeling is driven by vascular aberrations that are reported in human gestational complications such as infertility, recurrent spontaneous abortion, preeclampsia (PE) and fetal growth restriction. Appropriate maternal cardiovascular responses during pregnancy protect mothers and their children from later cardiovascular disease risk elevation. One of the earliest uterine responses to pregnancy in species with hemochorial placentation is stromal cell decidualization, which creates unique niches for angiogenesis and leukocyte recruitment. In early decidua basalis, the aspect of the implantation site that will cradle the developing placenta and provide the major blood vessels to support mature placental functions, leukocytes are greatly enriched and display specialized properties. UNK cells, the most abundant leukocyte subset in early decidua basalis, have angiogenic abilities and are essential for normal early decidual angiogenesis. The regulation of uNK cells and their roles in determining maternal and progeny cardiovascular health over pregnancy and postpartum are discussed. PMID:25066422

  7. Improved survival of newborns receiving leukocyte transfusions for sepsis

    SciTech Connect

    Cairo, M.S.; Rucker, R.; Bennetts, G.A.; Hicks, D.; Worcester, C.; Amlie, R.; Johnson, S.; Katz, J.

    1984-11-01

    To determine the role of polymorphonuclear (PMN) leukocyte transfusions in neonates with sepsis, 23 consecutive newborns were prospectively randomly selected during an 18-month period in a treatment plan to receive polymorphonuclear leukocyte transfusions with supportive care or supportive care alone. Thirteen neonates received transfusions every 12 hours for a total of five transfusions. Each transfusion consisting of 15 mL/kg of polymorphonuclear leukocytes was subjected to 1,500 rads of radiation. The polymorphonuclear leukocytes were obtained by continuous-flow centrifugation leukapheresis and contained 0.5 to 1.0 X 10(9) granulocytes per 15 mL with less than 10% lymphocytes. Positive findings on blood cultures were obtained in 14/23 patients and seven were randomly selected for each treatment group. Absolute granulocyte counts were less than 1,500/microL in 13 patients but tibial bone marrow examinations revealed that the neutrophil supply pool was depleted in only three patients. The survival was significantly greater in the treatment group compared with the group that did not receive transfusions.

  8. Intracellular Penetration and Activity of Gemifloxacin in Human Polymorphonuclear Leukocytes

    PubMed Central

    García, Isabel; Pascual, Alvaro; Ballesta, Sofía; Joyanes, Providencia; Perea, Evelio J.

    2000-01-01

    The intracellular penetration and activity of gemifloxacin in human polymorphonuclear leukocytes (PMN) were evaluated. Gemifloxacin reached intracellular concentrations eight times higher than extracellular concentrations. The uptake was rapid, reversible, and nonsaturable and was affected by environmental temperature, cell viability, and membrane stimuli. At therapeutic extracellular concentrations, gemifloxacin showed intracellular activity against Staphylococcus aureus. PMID:11036051

  9. Multiparticle adhesive dynamics: Hydrodynamic recruitment of rolling leukocytes

    PubMed Central

    King, Michael R.; Hammer, Daniel A.

    2001-01-01

    The slow rolling motion of leukocytes along the walls of blood vessels mediated by specific receptor-ligand adhesion is important in inflammation and occurs in postcapillary venules over a wide range of wall shear stresses and vessel diameters. The ability of hydrodynamic collisions between cells to induce capture of free-stream leukocytes to a selectin-bearing surface under shear flow was studied experimentally by using a cell-free assay. It was found that carbohydrate-coated spherical beads, representing model leukocytes, tend to attach to the adhesive wall 4–5 cell diameters up- or downstream of a slowly rolling or stationary adhesive bead. A key feature of such “hydrodynamic recruitment” is that only glancing, indirect collisions occurring close to the plane will result in downstream attachment. A direct numerical simulation of cell capture and rolling that includes multiparticle hydrodynamic interactions is shown to reproduce the observed behavior accurately. The theory predicts that hydrodynamic recruitment will occur in the absence of buoyancy effects and over a range of shear rates, suggesting that the mechanism may be important in vivo. This theory is supported by measurements of leukocyte capture in vivo using the hamster cheek pouch model. PMID:11752440

  10. Differential MSC activation leads to distinct mononuclear leukocyte binding mechanisms

    NASA Astrophysics Data System (ADS)

    Kota, Daniel J.; Dicarlo, Bryan; Hetz, Robert A.; Smith, Philippa; Cox, Charles S.; Olson, Scott D.

    2014-04-01

    Advances in the field of Multipotent Mesenchymal Stromal cell (MSC) biology have demonstrated that MSCs can improve disease outcome when `activated' to exert immunomodulatory effects. However, the precise mechanisms modulating MSC-immune cells interactions remain largely elusive. In here, we activated MSC based on a recent polarization paradigm, in which MSCs can be polarized towards a pro- or anti-inflammatory phenotype depending on the Toll-like receptor stimulated, to dissect the mechanisms through which MSCs physically interact with and modulate leukocytes in this context. Our data show that MSCs activated through the Toll-like receptor (TLR) 4 pathway increased VCAM-1 and ICAM-1 dependent binding of leukocytes. On the other hand, TLR3 stimulation strongly increases leukocytes affinity to MSC comparatively, through the formation of cable-like hyaluronic acid structures. In addition, TLR4 activation elicited secretion of pro-inflammatory mediators by MSCs, whereas TLR3-activated MSCs displayed a milder pro-inflammatory phenotype, similar to inactivated MSCs. However, the differently activated MSCs maintained their ability to suppress leukocyte activation at similar levels in our in vitro model, and this immunomodulatory property was shown here to be partially mediated by prostaglandin. These results reinforce the concept that alternate activation profiles control MSC responses and may impact the therapeutic use of MSCs.

  11. The spreading of leukocytes released from their liquid environment.

    PubMed

    Cuadra, M

    1978-08-15

    It is known that while leukocytes in conventional blood smears reveal their structures, in smears of erythrocyte-free suspension (EFS) they show a tendency to pyknosis. From the present study it appears that: 1. When any leukocyte suspension is subjected to drying on slides the cells undergo shrinkage (pyknosis in stained state) because their water content is extracted by the suspending fluid that is rendered increasingly hypertonic during drying. 2. When the leukocytes, which while floating within physiological fluids are ball-shaped, are entirely released from their suspending fluid, they suddenly spread into flat cells because the capillary force between the cell membranes and glass overcomes the surface tension of the cells. 3. In contrast to shrunken or even normal (spherical) cells, spread cells are able to display their morphology. Using the smear technique, the cell density of the suspension will determine whether spreading or shrinkage are to occur; with normal blood (high density) the release and consequently the spread are achieved; with EFS (usually of low density) an inadequate release and consequently shrinkage occur. 4. A device (cell spreader) for spreading leukocytes of EFS is presented. PMID:678682

  12. Leukocyte driven-decidual angiogenesis in early pregnancy

    PubMed Central

    Lima, Patricia DA; Zhang, Jianhong; Dunk, Caroline; Lye, Stephen J; Anne Croy, B

    2014-01-01

    Successful pregnancy and long-term, post-natal maternal and offspring cardiac, vascular and metabolic health require key maternal cardiovascular adaptations over gestation. Within the pregnant decidualizing uterus, coordinated vascular, immunological and stromal cell changes occur. Considerable attention has been given to the roles of uterine natural killer (uNK) cells in initiating decidual spiral arterial remodeling, a process normally completed by mid-gestation in mice and in humans. However, leukocyte roles in much earlier, region specific, decidual vascular remodeling are now being defined. Interest in immune cell-promoted vascular remodeling is driven by vascular aberrations that are reported in human gestational complications such as infertility, recurrent spontaneous abortion, preeclampsia (PE) and fetal growth restriction. Appropriate maternal cardiovascular responses during pregnancy protect mothers and their children from later cardiovascular disease risk elevation. One of the earliest uterine responses to pregnancy in species with hemochorial placentation is stromal cell decidualization, which creates unique niches for angiogenesis and leukocyte recruitment. In early decidua basalis, the aspect of the implantation site that will cradle the developing placenta and provide the major blood vessels to support mature placental functions, leukocytes are greatly enriched and display specialized properties. UNK cells, the most abundant leukocyte subset in early decidua basalis, have angiogenic abilities and are essential for normal early decidual angiogenesis. The regulation of uNK cells and their roles in determining maternal and progeny cardiovascular health over pregnancy and postpartum are discussed. PMID:25066422

  13. Uptake of radiolabeled leukocytes in prosthetic graft infection

    SciTech Connect

    Serota, A.I.; Williams, R.A.; Rose, J.G.; Wilson, S.E.

    1981-07-01

    The utility of radionuclide labeled leukocytes in the demonstration of infection within vascular prostheses was examined. The infrarenal aorta was replaced with a 3 cm Dacron graft in 12 dogs. On the third postoperative day, six of the animals received an intravenous injection of 10(8) Staphylococcus aureus. Labeled leukocyte scans were performed at postoperative days one and three, and then weekly for 8 weeks with indium-111 and technetium-99 labeled autologous leukocytes. When scans showed focal uptake of isotope in the area of prosthetic material, the grafts were aseptically excised and cultured on mannitol-salt agar. Both control and infected animals had retroperitoneal isotope activity in the immediate postoperative period that disappeared by the end of the first week. By the eighth postoperative week, all of the animals that received the bacteremic challenge had both radionuclide concentration in the region of the vascular prosthesis and S. aureus cultured subsequently from the perigraft tissues. None of the control animals had either radionuclide or bacteriologic evidence of infection at the eighth postoperative week. The radiolabeled leukocyte scan is a highly sensitive and specific technique, clinically applicable for the diagnosis of vascular prosthetic infections.

  14. Secretory leukocyte proteinase inhibitor is a major leukocyte elastase inhibitor in human neutrophils.

    PubMed

    Sallenave, J M; Si Tahar, M; Cox, G; Chignard, M; Gauldie, J

    1997-06-01

    Secretory leukocyte proteinase inhibitor (SLPI) is the main neutrophil elastase (HLE) inhibitor found in the upper airways during pulmonary inflammation. It has been shown to be synthesized and secreted in vitro by epithelial cells and has been localized in tracheal glands and bronchiolar epithelial cells by immunocytochemistry. In this study, using immunodetection and immunopurification techniques with specific anti-SLPI immunoglobulin G (IgG), we show that SLPI is present as a native 14-kDa molecule in neutrophil cytosol. In addition, we demonstrate that SLPI is the major inhibitor of HLE present in neutrophil cytosol because pre-incubation with specific anti-SLPI IgG was able to inhibit completely the anti-HLE activity of the cytosol. SLPI can be secreted (probably in an inactive form) by neutrophils and its secretion is enhanced when the cells are stimulated with phorbol myristate acetate (PMA). Elafin, an elastase-specific inhibitor, is also present in minute amounts in neutrophil cytosol and its secretion can be up-regulated. The presence of SLPI in the cytosol of neutrophils may serve as a protective screen against proteinases spilling from azurophilic granules. An alternative or supplementary role may be the maintenance of a differentiated phenotype. PMID:9201260

  15. LINEAR ACCELERATOR

    DOEpatents

    Colgate, S.A.

    1958-05-27

    An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.

  16. In vivo compartmental analysis of leukocytes in mouse lungs.

    PubMed

    Patel, Brijesh V; Tatham, Kate C; Wilson, Michael R; O'Dea, Kieran P; Takata, Masao

    2015-10-01

    The lung has a unique structure consisting of three functionally different compartments (alveolar, interstitial, and vascular) situated in an extreme proximity. Current methods to localize lung leukocytes using bronchoalveolar lavage and/or lung perfusion have significant limitations for determination of location and phenotype of leukocytes. Here we present a novel method using in vivo antibody labeling to enable accurate compartmental localization/quantification and phenotyping of mouse lung leukocytes. Anesthetized C57BL/6 mice received combined in vivo intravenous and intratracheal labeling with fluorophore-conjugated anti-CD45 antibodies, and lung single-cell suspensions were analyzed by flow cytometry. The combined in vivo intravenous and intratracheal CD45 labeling enabled robust separation of the alveolar, interstitial, and vascular compartments of the lung. In naive mice, the alveolar compartment consisted predominantly of resident alveolar macrophages. The interstitial compartment, gated by events negative for both intratracheal and intravenous CD45 staining, showed two conventional dendritic cell populations, as well as a Ly6C(lo) monocyte population. Expression levels of MHCII on these interstitial monocytes were much higher than on the vascular Ly6C(lo) monocyte populations. In mice exposed to acid aspiration-induced lung injury, this protocol also clearly distinguished the three lung compartments showing the dynamic trafficking of neutrophils and exudative monocytes across the lung compartments during inflammation and resolution. This simple in vivo dual-labeling technique substantially increases the accuracy and depth of lung flow cytometric analysis, facilitates a more comprehensive examination of lung leukocyte pools, and enables the investigation of previously poorly defined "interstitial" leukocyte populations during models of inflammatory lung diseases. PMID:26254421

  17. Fecal Leukocytes in Children Infected with Diarrheagenic Escherichia coli▿

    PubMed Central

    Mercado, Erik H.; Ochoa, Theresa J.; Ecker, Lucie; Cabello, Martin; Durand, David; Barletta, Francesca; Molina, Margarita; Gil, Ana I.; Huicho, Luis; Lanata, Claudio F.; Cleary, Thomas G.

    2011-01-01

    The purpose of this study was to determine the presence and quantity of fecal leukocytes in children infected with diarrheagenic Escherichia coli and to compare these levels between diarrhea and control cases. We analyzed 1,474 stool samples from 935 diarrhea episodes and 539 from healthy controls of a cohort study of children younger than 2 years of age in Lima, Peru. Stools were analyzed for common enteric pathogens, and diarrheagenic E. coli isolates were studied by a multiplex real-time PCR. Stool smears were stained with methylene blue and read by a blinded observer to determine the number of polymorphonuclear leukocytes per high-power field (L/hpf). Fecal leukocytes at >10 L/hpf were present in 11.8% (110/935) of all diarrheal episodes versus 1.1% (6/539) in controls (P < 0.001). Among stool samples with diarrheagenic E. coli as the only pathogen isolated (excluding coinfection), fecal leukocytes at >10 L/hpf were present in 8.5% (18/212) of diarrhea versus 1.3% (2/157) of control samples (P < 0.01). Ninety-five percent of 99 diarrheagenic E. coli diarrhea samples were positive for fecal lactoferrin. Adjusting for the presence of blood in stools, age, sex, undernutrition, and breastfeeding, enterotoxigenic E. coli (ETEC) isolation as a single pathogen, excluding coinfections, was highly associated with the presence of fecal leukocytes (>10 L/hpf) with an odds ratio (OR) of 4.1 (95% confidence interval [CI], 1.08 to 15.51; P < 0.05). Although diarrheagenic E. coli was isolated with similar frequencies in diarrhea and control samples, clearly it was associated with a more inflammatory response during symptomatic infection; however, in general, these pathogens elicited a mild inflammatory response. PMID:21325554

  18. Fecal leukocytes in children infected with diarrheagenic Escherichia coli.

    PubMed

    Mercado, Erik H; Ochoa, Theresa J; Ecker, Lucie; Cabello, Martin; Durand, David; Barletta, Francesca; Molina, Margarita; Gil, Ana I; Huicho, Luis; Lanata, Claudio F; Cleary, Thomas G

    2011-04-01

    The purpose of this study was to determine the presence and quantity of fecal leukocytes in children infected with diarrheagenic Escherichia coli and to compare these levels between diarrhea and control cases. We analyzed 1,474 stool samples from 935 diarrhea episodes and 539 from healthy controls of a cohort study of children younger than 2 years of age in Lima, Peru. Stools were analyzed for common enteric pathogens, and diarrheagenic E. coli isolates were studied by a multiplex real-time PCR. Stool smears were stained with methylene blue and read by a blinded observer to determine the number of polymorphonuclear leukocytes per high-power field (L/hpf). Fecal leukocytes at >10 L/hpf were present in 11.8% (110/935) of all diarrheal episodes versus 1.1% (6/539) in controls (P < 0.001). Among stool samples with diarrheagenic E. coli as the only pathogen isolated (excluding coinfection), fecal leukocytes at >10 L/hpf were present in 8.5% (18/212) of diarrhea versus 1.3% (2/157) of control samples (P < 0.01). Ninety-five percent of 99 diarrheagenic E. coli diarrhea samples were positive for fecal lactoferrin. Adjusting for the presence of blood in stools, age, sex, undernutrition, and breastfeeding, enterotoxigenic E. coli (ETEC) isolation as a single pathogen, excluding coinfections, was highly associated with the presence of fecal leukocytes (>10 L/hpf) with an odds ratio (OR) of 4.1 (95% confidence interval [CI], 1.08 to 15.51; P < 0.05). Although diarrheagenic E. coli was isolated with similar frequencies in diarrhea and control samples, clearly it was associated with a more inflammatory response during symptomatic infection; however, in general, these pathogens elicited a mild inflammatory response. PMID:21325554

  19. Two-step model of leukocyte-endothelial cell interaction in inflammation: distinct roles for LECAM-1 and the leukocyte beta 2 integrins in vivo.

    PubMed Central

    von Andrian, U H; Chambers, J D; McEvoy, L M; Bargatze, R F; Arfors, K E; Butcher, E C

    1991-01-01

    The lectin homing receptor LECAM-1 (LAM-1, Leu8) and the beta 2 integrins, particularly Mac-1 (CD11b/CD18), participate in leukocyte-endothelial cell interactions in inflammation. LECAM-1 is rapidly shed while Mac-1 expression is dramatically increased upon neutrophil activation, suggesting functionally distinct roles for these molecules. Using intravital video microscopy, we have compared the effect of antibodies against LECAM-1 and CD18 on leukocyte interactions with rabbit mesenteric venules. Anti-LECAM-1 monoclonal antibody and its Fab fragments inhibited initial reversible leukocyte rolling along the vascular wall. Anti-CD18 monoclonal antibody had no effect on rolling but prevented subsequent firm attachment of leukocytes to venular endothelium. These results support a two-step model of leukocyte-endothelial cell interactions: reversible rolling mediated in part by LECAM-1 facilitates leukocyte recruitment by the local microenvironment and precedes activation-dependent firm attachment involving beta 2 integrins. Images PMID:1715568

  20. An approximate simulation model for initial luge track design.

    PubMed

    Mössner, Martin; Hasler, Michael; Schindelwig, Kurt; Kaps, Peter; Nachbauer, Werner

    2011-03-15

    Competitive and recreational sport on artificial ice tracks has grown in popularity. For track design one needs knowledge of the expected speed and acceleration of the luge on the ice track. The purpose of this study was to develop an approximate simulation model for luge in order to support the initial design of new ice tracks. Forces considered were weight, drag, friction, and surface reaction force. The trajectory of the luge on the ice track was estimated using a quasi-static force balance and a 1d equation of motion was solved along that trajectory. The drag area and the coefficient of friction for two runs were determined by parameter identification using split times of five sections of the Whistler Olympic ice track. The values obtained agreed with experimental data from ice friction and wind tunnel measurements. To validate the ability of the model to predict speed and accelerations normal to the track surface, a luge was equipped with an accelerometer to record the normal acceleration during the entire run. Simulated and measured normal accelerations agreed well. In a parameter study the vertical drop and the individual turn radii turned out to be the main variables that determine speed and acceleration. Thus the safety of a new ice track is mainly ensured in the planning phase, in which the use of a simulation model similar to this is essential. PMID:21185562

  1. Acceleration switch

    DOEpatents

    Abbin, J.P. Jr.; Devaney, H.F.; Hake, L.W.

    1979-08-29

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  2. Acceleration switch

    DOEpatents

    Abbin, Jr., Joseph P.; Devaney, Howard F.; Hake, Lewis W.

    1982-08-17

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  3. ION ACCELERATOR

    DOEpatents

    Bell, J.S.

    1959-09-15

    An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

  4. LINEAR ACCELERATOR

    DOEpatents

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  5. Track Construction Manual.

    ERIC Educational Resources Information Center

    Banke, Ron; Di Gennaro, Guy; Ediger, Rick; Garner, Lanny; Hersom, Steve; Miller, Jack; Nemeth, Ron; Petrucelli, Jim; Sierks, Donna; Smith, Don; Swank, Kevin; West, Kevin

    This book establishes guidelines for the construction and maintenance of tracks by providing information for building new tracks or upgrading existing tracks. Subjects covered include running track planning and construction, physical layout, available surfaces, and maintenance. General track requirements and construction specifications are…

  6. On the Right Track.

    ERIC Educational Resources Information Center

    Bieber, Ed

    1983-01-01

    Suggests thinking of "tracks" as clues and using them as the focus of outdoor activities in the urban environment. Provides 24 examples of possible track activities, including: seeds on the ground (track of a nearby tree), litter (track of a litterbug), and peeling paint (track of weathering forces). (JN)

  7. An observer-based consensus tracking control and application to event-triggered tracking

    NASA Astrophysics Data System (ADS)

    Hu, Jiangping; Geng, Ji; Zhu, Hong

    2015-02-01

    Leader-follower mechanism provides an important framework for multi-agent consensus problems. In this paper, a consensus tracking problem is investigated for a second-order multi-agent system with a self-active leader. The input (acceleration) to the leader is assumed to be time-varying and unavailable to followers. An observer-based consensus tracking control is designed on the basis of a novel distributed velocity estimation technique. The ultimate boundedness and the stability of the tracking error system are analyzed by virtue of an Input-State-Stability (ISS) Lyapunov function approach. Then, the dynamic consensus tracking control is applied to solve an event-triggered tracking problem. Finally, some numerical simulation results are presented to demonstrate the effectiveness of the proposed consensus tracking control.

  8. Modulation of leukocyte adhesion in rat mesenteric venules by aspirin and salicylate.

    PubMed

    Asako, H; Kubes, P; Wallace, J; Wolf, R E; Granger, D N

    1992-07-01

    Erythrocyte velocity, vessel diameter, leukocyte rolling velocity, and number of adherent and emigrated leukocytes were measured in postcapillary venules both before and during superfusion of rat mesentery with either aspirin or sodium salicylate. In some experiments, animals were treated with either a leukotriene (LT)-synthesis inhibitor (L-663,536), an LTD4 antagonist (MK-571), an LTB4 antagonist (SC-41930), misoprostol, or prostaglandin (PG) I2, then the aspirin protocol was repeated. Superfusion of aspirin but not sodium salicylate resulted in increased leukocyte adherence and a reduced leukocyte rolling velocity but did not affect leukocyte emigration. Aspirin-induced leukocyte adhesion was effectively prevented by the LT-synthesis inhibitor and LTB4 antagonist but not by the LTD4 antagonist. Misoprostol and PGI2 also prevented the aspirin-induced adhesion responses. Superfusion of the mesentery with either platelet-activating factor (PAF) or LTB4 enhanced leukocyte adherence and emigration while reducing leukocyte rolling velocity. Sodium salicylate prevented all of the adhesion responses elicited by LTB4. Although salicylate did not affect the PAF-induced leukocyte adherence and rolling responses, it completely prevented the increased leukocyte emigration. These results indicate that aspirin promotes, whereas sodium salicylate inhibits, leukocyte-endothelial cell adhesive interactions at therapeutically relevant concentrations. PMID:1319367

  9. Combined bone scintigraphy and indium-111 leukocyte scans in neuropathic foot disease

    SciTech Connect

    Schauwecker, D.S.; Park, H.M.; Burt, R.W.; Mock, B.H.; Wellman, H.N.

    1988-10-01

    It is difficult to diagnose osteomyelitis in the presence of neurotrophic osteoarthropathy. We performed combined (99mTc)MDP bone scans and indium-111 (111In) leukocyte studies on 35 patients who had radiographic evidence of neuropathic foot disease and clinically suspected osteomyelitis. The (111In)leukocyte study determined if there was an infection and the bone scan provided the anatomic landmarks so that the infection could be localized to the bone or the adjacent soft tissue. Seventeen patients had osteomyelitis and all showed increased (111In)leukocyte activity localized to the bone, giving a sensitivity of 100%. Among the 18 patients without osteomyelitis, eight had no accumulation of (111In)leukocytes, seven had the (111In)leukocyte activity correctly localized to the soft tissue, two had (111In)leukocyte activity mistakenly attributed to the bone, and one had (111In)leukocyte accumulation in a proven neuroma which was mistakenly attributed to bone. These three false-positive results for osteomyelitis reduced the specificity to 83%. Considering only the 27 patients with a positive (111In)leukocyte study, the combined bone scan and (111In)leukocyte study correctly localized the infection to the soft tissues or bone in 89%. Uninfected neurotrophic osteoarthropathy does not accumulate (111In)leukocytes. We found the combined bone scan and (111In) leukocyte study useful for the detection and localization of infection to soft tissue or bone in patients with neuropathic foot disease.

  10. The effects of space flight on polymorphonuclear leukocyte response experiment MA-032

    NASA Technical Reports Server (NTRS)

    Martin, R. R.

    1976-01-01

    In a series of studies performed at intervals from 30 day before flight to 30 days after recovery, blood samples were obtained from the three astronauts of the Apollo Soyuz Test Project and from eight control subjects. To determine the effects of space flight on polymorphonuclear leukocytes, tests were performed on blood samples obtained as quickly as possible after splashdown and on the day following recovery. The astronauts' inhalation of propellant gases and the inception of corticosteroid therapy 1 day after recovery provided an additional opportunity to investigate the possible effects of these factors on leukocyte function. Data were obtained during each time period on the total leukocyte count, differential count, leukocyte adhesion, leukocyte migration and chemotaxis, phagocytosis, and histochemical staining for leukocyte acid and alkaline phosphatase. These observations present a variety of in vitro correlates to white blood cell function within the body. Taken together, they serve as a reasonable approximation of the effects of space flight on leukocyte function.

  11. Big insights from small volumes: deciphering complex leukocyte behaviors using microfluidics.

    PubMed

    Irimia, Daniel; Ellett, Felix

    2016-08-01

    Inflammation is an indispensable component of the immune response, and leukocytes provide the first line of defense against infection. Although the major stereotypic leukocyte behaviors in response to infection are well known, the complexities and idiosyncrasies of these phenotypes in conditions of disease are still emerging. Novel tools are indispensable for gaining insights into leukocyte behavior, and in the past decade, microfluidic technologies have emerged as an exciting development in the field. Microfluidic devices are readily customizable, provide tight control of experimental conditions, enable high precision of ex vivo measurements of individual as well as integrated leukocyte functions, and have facilitated the discovery of novel leukocyte phenotypes. Here, we review some of the most interesting insights resulting from the application of microfluidic approaches to the study of the inflammatory response. The aim is to encourage leukocyte biologists to integrate these new tools into increasingly more sophisticated experimental designs for probing complex leukocyte functions. PMID:27194799

  12. Radio tracking system

    NASA Technical Reports Server (NTRS)

    Breidenthal, J. C.; Komarek, T. A.

    1982-01-01

    The principles and techniques of deep space radio tracking are described along with the uses of tracking data in navigation and radio science. Emphasis is placed on the measurement functions of radio tracking.

  13. Delayed healing and induction of secretory leukocyte protease inhibitor in polycystic ovary syndrome rat skin wounds.

    PubMed

    Jeong, Soon-Jeong; Kim, Sung-Shin; Bae, Chun-Sik; Park, Jin-Ju; Choi, Baik-Dong; Wang, Guanlin; Jung, Myung-Ju; Jang, Hyun-Sun; Kim, Byung-Ock; Lim, Do-Seon; Cho, Young-Sik; Jeong, Moon-Jin

    2012-02-01

    Secretory leukocyte protease inhibitor (SLPI) and estrogen promote wound healing through a decrease in the excessive inflammatory response, accelerating re-epithelialization and increasing the amount of collagen deposition. The excessive administration of estradiol valerate (EV) using hormonal therapy decreases the concentration of estrogen abruptly and induces the polycystic ovary syndrome (PCOS). In this study, the PCOS rat skin wound area was wider than that of the normal groups and the rate of keratinocyte migration in PCOS was lower than the normal group. The numbers of inflammatory cells and macrophages recruited in the PCOS group were larger than that of the normal group. More collagen was deposited in the healing area of the normal group than in the PCOS group. The level of SLPI expression was higher in the PCOS group than the normal group after wounding, with the exception of the epithelium. On the other hand, mRNA and protein expression levels of transforming growth factor-β1 (TGF-β1) were lower in the PCOS group than in the normal group. Matrix metalloproteinase-2 (MMP-2) and MMP-9 levels in the PCOS group were significantly lower than that of the normal group. Therefore, increased SLPI in PCOS skin wounds may help prevent an excessive inflammatory response and aberrant collagen deposition but not are sufficient to accelerate PCOS skin wound healing, suggesting that SLPI may act as a local rather than a systemic modulating molecule in PCOS rat skin wounds. PMID:22020578

  14. [Comparative transcriptome analysis of human aorta atherosclerotic lesions and peripheral blood leukocytes from essential hypertension patients].

    PubMed

    Timofeeva, A V; Goriunova, L E; Khaspekov, G L; Il'inskaia, O P; Sirotkin, V N; Andreeva, E R; Tararak, E M; Bulkina, O S; Buza, V V; Britareva, V V; Karpov, Iu A; Bibilashvili, R Sh

    2009-01-01

    One of the major cardiovascular risk factor which predisposes to and accelerates atherosclerosis is arterial hypertension (AH). To determine the molecular basis of the crosslink between AH and atherosclerosis for the development of new treatment strategies large-scale transcriptome analysis of the cells implicated in atherogenesis is needed. We used cDNA microarray technique for simultaneous analysis of gene expression in human abdominal aorta normal sites and atherosclerotic lesions of different histological types, as well as in peripheral blood leukocytes from patients with essential hypertension (EH) and donors. The microarray data were verified by quantitative RT-PCR (reverse transcription coupled with polymerase chain reaction) and immunohistochemical analysis. Differential expression of 40 genes has been found, among which twenty two genes demonstrated up-regulation and 18 genes demonstrated down-regulation in atherosclerotic aorta compared with normal vessel. New gene-candidates, implicated in atherogenesis, have been identified - FPRL2, CD37, CD53, RGS1, LCP1, SPI1, CTSA, EPAS1, FHL1, GEM, RHOB, SPARCL1, ITGA8, PLN, and COL14A1. These genes participate in cell migration and adhesion, phenotypic changes of smooth muscle cells, immune and inflammatory reactions, oxidative processes and extracellular matrix remodeling. We have found increased expression levels of CD53, SPI1, FPRL2, SPP1, CTSD, ACP5, LCP1, CTSA and LIPA genes in peripheral blood leukocytes from EH patients and in atherosclerotic lesions of human aorta. The majority of these genes significantly (p<0.005) positively (r>0.5) correlated with AH stage as well as with histological grading of atherosclerotic lesions. PMID:19772500

  15. Derivation of Cinnamon Blocks Leukocyte Attachment by Interacting with Sialosides.

    PubMed

    Lin, Wei-Ling; Guu, Shih-Yun; Tsai, Chan-Chuan; Prakash, Ekambaranellore; Viswaraman, Mohan; Chen, Hsing-Bao; Chang, Chuan-Fa

    2015-01-01

    Molecules derived from cinnamon have demonstrated diverse pharmacological activities against infectious pathogens, diabetes and inflammatory diseases. This study aims to evaluate the effect of the cinnamon-derived molecule IND02 on the adhesion of leukocytes to host cells. The anti-inflammatory ability of IND02, a pentameric procyanidin type A polyphenol polymer isolated from cinnamon alcohol extract, was examined. Pretreatment with IND02 significantly reduced the attachment of THP-1 cells or neutrophils to TNF-α-activated HUVECs or E-selectin/ICAM-1, respectively. IND02 also reduced the binding of E-, L- and P-selectins with sialosides. Furthermore, IND02 could agglutinate human red blood cells (RBC), and the agglutination could be disrupted by sialylated glycoprotein. Our findings demonstrate that IND02, a cinnamon-derived compound, can interact with sialosides and block the binding of selectins and leukocytes with sialic acids. PMID:26076445

  16. Signaling networks regulating leukocyte podosome dynamics and function

    PubMed Central

    Dovas, Athanassios; Cox, Dianne

    2011-01-01

    Podosomes are ventral adhesion structures prominent in cells of the myeloid lineage. A common aspect of these cells is that they are highly motile and are required to traverse multiple tissue barriers in order to perform their functions. Recently podosomes have gathered attention from researchers as important cellular structures that can influence cell adhesion, motility and matrix remodeling. Adhesive and soluble ligands act via transmembrane receptors and propagate signals to the leukocyte cytoskeleton via small G proteins of the Rho family, tyrosine kinases and scaffold proteins and are able to induce podosome formation and rearrangements. Manipulation of the signals that regulate podosome formation and dynamics can therefore be a strategy to interfere with leukocyte functions in a multitude of pathological settings, such as infections, atherosclerosis and arthritis. Here, we review the major signaling molecules that act in the formation and regulation of podosomes. PMID:21342664

  17. Derivation of Cinnamon Blocks Leukocyte Attachment by Interacting with Sialosides

    PubMed Central

    Lin, Wei-Ling; Guu, Shih-Yun; Tsai, Chan-Chuan; Prakash, Ekambaranellore; Viswaraman, Mohan; Chen, Hsing-Bao; Chang, Chuan-Fa

    2015-01-01

    Molecules derived from cinnamon have demonstrated diverse pharmacological activities against infectious pathogens, diabetes and inflammatory diseases. This study aims to evaluate the effect of the cinnamon-derived molecule IND02 on the adhesion of leukocytes to host cells. The anti-inflammatory ability of IND02, a pentameric procyanidin type A polyphenol polymer isolated from cinnamon alcohol extract, was examined. Pretreatment with IND02 significantly reduced the attachment of THP-1 cells or neutrophils to TNF-α-activated HUVECs or E-selectin/ICAM-1, respectively. IND02 also reduced the binding of E-, L- and P-selectins with sialosides. Furthermore, IND02 could agglutinate human red blood cells (RBC), and the agglutination could be disrupted by sialylated glycoprotein. Our findings demonstrate that IND02, a cinnamon-derived compound, can interact with sialosides and block the binding of selectins and leukocytes with sialic acids. PMID:26076445

  18. Acceleration Studies

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.

    1993-01-01

    Work to support the NASA MSFC Acceleration Characterization and Analysis Project (ACAP) was performed. Four tasks (analysis development, analysis research, analysis documentation, and acceleration analysis) were addressed by parallel projects. Work concentrated on preparation for and implementation of near real-time SAMS data analysis during the USMP-1 mission. User support documents and case specific software documentation and tutorials were developed. Information and results were presented to microgravity users. ACAP computer facilities need to be fully implemented and networked, data resources must be cataloged and accessible, future microgravity missions must be coordinated, and continued Orbiter characterization is necessary.

  19. Dimensions of religious involvement and leukocyte telomere length.

    PubMed

    Hill, Terrence D; Ellison, Christopher G; Burdette, Amy M; Taylor, John; Friedman, Katherine L

    2016-08-01

    Although numerous studies suggest that religious involvement is associated with a wide range of favorable health outcomes, it is unclear whether this general pattern extends to cellular aging. In this paper, we tested whether leukocyte telomere length varies according to several dimensions of religious involvement. We used cross-sectional data from the Nashville Stress and Health Study (2011-2014), a large probability sample of 1252 black and white adults aged 22 to 69 living in Davidson County, TN, USA. Leukocyte telomere length was measured using the monochrome multiplex quantitative polymerase chain reaction method with albumin as the single-copy reference sequence. Dimensions of religious involvement included religiosity, religious support, and religious coping. Our multivariate analyses showed that religiosity (an index of religious attendance, prayer frequency, and religious identity) was positively associated with leukocyte telomere length, even with adjustments for religious support, religious coping, age, gender, race, education, employment status, income, financial strain, stressful life events, marital status, family support, friend support, depressive symptoms, smoking, heavy drinking, and allostatic load. Unlike religiosity, religious support and religious coping were unrelated to leukocyte telomere length across models. Depressive symptoms, smoking, heavy drinking, and allostatic load failed to explain any of the association between religiosity and telomere length. To our knowledge, this is the first population-based study to link religious involvement and cellular aging. Although our data suggest that adults who frequently attend religious services, pray with regularity, and consider themselves to be religious tend to exhibit longer telomeres than those who attend and pray less frequently and do not consider themselves to be religious, additional research is needed to establish the mechanisms underlying this association. PMID:27174242

  20. Myxoma and Vaccinia Viruses Bind Differentially to Human Leukocytes

    PubMed Central

    Chan, Winnie M.; Bartee, Eric C.; Moreb, Jan S.; Dower, Ken; Connor, John H.

    2013-01-01

    Myxoma virus (MYXV) and vaccinia virus (VACV), two distinct members of the family Poxviridae, are both currently being developed as oncolytic virotherapeutic agents. Recent studies have demonstrated that ex vivo treatment with MYXV can selectively recognize and kill contaminating cancerous cells from autologous bone marrow transplants without perturbing the engraftment of normal CD34+ hematopoietic stem and progenitor cells. However, the mechanism(s) by which MYXV specifically recognizes and eliminates the cancer cells in the autografts is not understood. While little is known about the cellular attachment factor(s) exploited by MYXV for entry into any target cells, VACV has been shown to utilize cell surface glycosaminoglycans such as heparan sulfate (HS), the extracellular matrix protein laminin, and/or integrin β1. We have constructed MYXV and VACV virions tagged with the Venus fluorescent protein and compared their characteristics of binding to various human cancer cell lines as well as to primary human leukocytes. We report that the binding of MYXV or VACV to some adherent cell lines could be partially inhibited by heparin, but laminin blocked only VACV binding. In contrast to cultured fibroblasts, the binding of MYXV and VACV to a wide spectrum of primary human leukocytes could not be competed by either HS or laminin. Additionally, MYXV and VACV exhibited very different binding characteristics against certain select human leukocytes, suggesting that the two poxviruses utilize different cell surface determinants for the attachment to these cells. These results indicate that VACV and MYXV can exhibit very different oncolytic tropisms against some cancerous human leukocytes. PMID:23388707

  1. Quantitative reconstruction of leukocyte subsets using DNA methylation

    PubMed Central

    2014-01-01

    Background Cell lineage-specific DNA methylation patterns distinguish normal human leukocyte subsets and can be used to detect and quantify these subsets in peripheral blood. We have developed an approach that uses DNA methylation to simultaneously quantify multiple leukocyte subsets, enabling investigation of immune modulations in virtually any blood sample including archived samples previously precluded from such analysis. Here we assess the performance characteristics and validity of this approach. Results Using Illumina Infinium HumanMethylation27 and VeraCode GoldenGate Methylation Assay microarrays, we measure DNA methylation in leukocyte subsets purified from human whole blood and identify cell lineage-specific DNA methylation signatures that distinguish human T cells, B cells, NK cells, monocytes, eosinophils, basophils and neutrophils. We employ a bioinformatics-based approach to quantify these cell types in complex mixtures, including whole blood, using DNA methylation at as few as 20 CpG loci. A reconstruction experiment confirms that the approach could accurately measure the composition of mixtures of human blood leukocyte subsets. Applying the DNA methylation-based approach to quantify the cellular components of human whole blood, we verify its accuracy by direct comparison to gold standard immune quantification methods that utilize physical, optical and proteomic characteristics of the cells. We also demonstrate that the approach is not affected by storage of blood samples, even under conditions prohibiting the use of gold standard methods. Conclusions Cell mixture distributions within peripheral blood can be assessed accurately and reliably using DNA methylation. Thus, precise immune cell differential estimates can be reconstructed using only DNA rather than whole cells. PMID:24598480

  2. Indium-111 leukocyte scintigraphy in Wegener's granulomatosis involving the spleen

    SciTech Connect

    Morayati, S.J.; Fink-Bennett, D.

    1986-12-01

    Indium-111-labeled leukocyte scintigraphy was performed on a 44-yr-old man to exclude an occult abscess. Four- and twenty-four-hour images of the abdomen revealed splenic photopenia except for a rim of activity medially. A subsequent computed tomography (CT) study demonstrated necrosis or hemorrhage of the spleen except for a medial rim. Exploratory laparotomy demonstrated necrotizing vasculitis with granuloma formation consistent with Wegener's granulomatosis and a rim of viable splenic tissue corresponding to the radionuclide and CT studies.

  3. Indium-111 leukocyte localization in infected prosthetic graft

    SciTech Connect

    Purnell, G.L.; Walker, C.W.; Allison, J.W.; Dalrymple, G.V. )

    1990-08-01

    Infective endocarditis can be difficult to prove, even in the face of strong clinical suspicion. A case in which standard methods of diagnosis failed to demonstrate endocarditis in a patient with recurrent Staphylococcus aureus bacteremia and porcine aortic valve is reported. An In-111 labelled leukocyte SPECT study demonstrated uptake in the aortic root and leaflets, and autopsy demonstrated vegetations on the leaflets. In-111 may prove useful in demonstrating endocarditis in patients with prosthetic valve infection.

  4. Leukocyte Trafficking to the Small Intestine and Colon.

    PubMed

    Habtezion, Aida; Nguyen, Linh P; Hadeiba, Husein; Butcher, Eugene C

    2016-02-01

    Leukocyte trafficking to the small and large intestines is tightly controlled to maintain intestinal immune homeostasis, mediate immune responses, and regulate inflammation. A wide array of chemoattractants, chemoattractant receptors, and adhesion molecules expressed by leukocytes, mucosal endothelium, epithelium, and stromal cells controls leukocyte recruitment and microenvironmental localization in intestine and in the gut-associated lymphoid tissues (GALTs). Naive lymphocytes traffic to the gut-draining mesenteric lymph nodes where they undergo antigen-induced activation and priming; these processes determine their memory/effector phenotypes and imprint them with the capacity to migrate via the lymph and blood to the intestines. Mechanisms of T-cell recruitment to GALT and of T cells and plasmablasts to the small intestine are well described. Recent advances include the discovery of an unexpected role for lectin CD22 as a B-cell homing receptor GALT, and identification of the orphan G-protein-coupled receptor 15 (GPR15) as a T-cell chemoattractant/trafficking receptor for the colon. GPR15 decorates distinct subsets of T cells in mice and humans, a difference in species that could affect translation of the results of mouse colitis models to humans. Clinical studies with antibodies to integrin α4β7 and its vascular ligand mucosal vascular addressin cell adhesion molecule 1 are proving the value of lymphocyte trafficking mechanisms as therapeutic targets for inflammatory bowel diseases. In contrast to lymphocytes, cells of the innate immune system express adhesion and chemoattractant receptors that allow them to migrate directly to effector tissue sites during inflammation. We review the mechanisms for innate and adaptive leukocyte localization to the intestinal tract and GALT, and discuss their relevance to human intestinal homeostasis and inflammation. PMID:26551552

  5. A study on task difficulty and acceleration stress

    NASA Technical Reports Server (NTRS)

    Repperger, D. W.; Rogers, D. B.

    1981-01-01

    The results of two experiments which relate to task difficulty and the effects of environmental stress on tracking performance are discussed and compared to subjective evaluations. The first experiment involved five different sum of sine tracking tasks which humans tracked both in a static condition and under a 5 Gz acceleration stress condition. The second experiment involved similar environmental stress conditions but in this case the tasks were constructed from deterministic functions with specially designed velocity and acceleration profiles. Phase Plane performance analysis was conducted to study potential measures of workload or tracking difficulty.

  6. Leukocyte recovery from umbilical cord blood by poligeline.

    PubMed

    Perutelli, P; Catellani, S

    1999-02-01

    Umbilical cord blood (UCB) collected at delivery is a source of transplantable stem/progenitor cells; it represents an alternative to bone marrow to restore hematopoiesis in patients affected by malignant and non-malignant disease. Therefore, large-scale UCB banks would be a natural complement to bone marrow donor registries. Storage of unmanipulated whole UCB units requires a great number of liquid nitrogen containers. Separation of leukocytes allows UCB storage in smaller space, thus lowering banking costs; unfortunately, UCB processing may cause significant losses of stem cells. We report about the use of poligeline to remove erythrocytes from UCB units. After erythrocyte sedimentation at 1xg (30' or 40') or 50xg, leukocyte-rich supernatant was collected and centrifuged to recover the leukocyte pool in view of stem cell transplantation. Erythrocyte depletion was always satisfactory, ranging from 82.6% to 88.9%, but 1xg sedimentation for 40' enabled us to achieve the best CD34+ cell recovery (mean value 80.5%). The proposed UCB-processing method allowed us to lower the final sample volume down to 1/10 of the initial one, in this way making UCB banking feasible. Erythrocyte depletion took place directly in the collection bag, thus reducing microbial contamination risk. PMID:10193639

  7. Curcumin modulates leukocyte and platelet adhesion in murine sepsis

    PubMed Central

    Vachharajani, Vidula; Wang, Si-Wei; Mishra, Nilamadhab; El-Gazzar, Mohammad; Yoza, Barbara; McCall, Charles

    2010-01-01

    Objective Circulating cell-endothelial cell interaction in sepsis is a rate-determining factor in organ dysfunction, and interventions targeting this process have a potential therapeutic value. In this project, we examined whether curcumin, an active ingredient of turmeric and an anti-inflammatory agent, could disrupt interactions between circulating blood cells and endothelium and improve survival in a murine model of sepsis. Methods Mice were subjected to cecal ligation and puncture (CLP) to induce sepsis vs. sham surgery. We studied leukocyte and platelet adhesion in cerebral microcirculation using intravital fluorescent video microscopy technique, blood brain barrier dysfunction using Evans Blue leakage method, P-selectin expression using dual radiolabeling technique and survival in mice subjected to Sham, CLP and CLP with curcumin pre-treatment (CLP+Curcumin). Results Curcumin significantly attenuated leukocyte and platelet adhesion in cerebral microcirculation, Evans Blue leakage in the brain tissue and improved survival in mice with CLP. P-selectin expression in mice with CLP+Curcumin was significantly attenuated compared to CLP in various microcirculatory beds including brain. Reduction in platelet adhesion was predominantly via modulation of endothelium by curcumin. Conclusion Curcumin pre-treatment modulates leukocyte and platelet adhesion and blood brain barrier dysfunction in mice with CLP via P-selectin expression and improves survival in mice with CLP. PMID:20690979

  8. Exposure to mercury alters early activation events in fish leukocytes.

    PubMed Central

    MacDougal, K C; Johnson, M D; Burnett, K G

    1996-01-01

    Although fish in natural populations may carry high body burdens of both organic and inorganic mercury, the effects of this divalent metal on such lower vertebrates is poorly understood. In this report, inorganic mercury in the form of mercuric chloride (HgCl2) is shown to produce both high-dose inhibition and low-dose activation of leukocytes in a marine teleost fish, Sciaenops ocellatus. Concentrations of inorganic mercury > or = 10 microM suppressed DNA synthesis and induced rapid influx of radiolabeled calcium, as well as tyrosine phosphorylation of numerous cellular proteins. Lower concentrations (0.1-1 microM) of HgCl2 that activated cell growth also induced a slow sustained rise in intracellular calcium in cells loaded with the calcium indicator dye fura-2, but did not produce detectable tyrosine phosphorylation of leukocyte proteins. These studies support the possibility that subtoxic doses of HgCl2 may inappropriately activate teleost leukocytes, potentially altering the processes that regulate the magnitude and specificity of the fish immune response to environmental pathogens. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. PMID:8930553

  9. Report: Nuclei segmentation of leukocytes in blood smear digital images.

    PubMed

    Abbas, Naveed; Mohamad, Dzulkifli; Abdullah, Abdul Hanan; Saba, Tanzila; Al-Rodhaan, Mznah; Al-Dhelaan, Abdullah

    2015-09-01

    The Leukocytes are differentiated from each other on the basis of their nuclei, demanded in many Medical studies, especially in all types of Leukemia by the Hematologists to note the disorder caused by specific type of Leukocyte. Leukemia is a life threatening disease. The work for diagnosing is manually carried out by the Hematologists involving much labor, time and human errors. The problems mentioned are easily addressed through computer vision techniques, but still accuracy and efficiency are demanded in terms of the basic and challenging step segmentation of Leukocyte's nuclei. The underlying study proposed better method in terms of accuracy and efficiency by designing a dynamic convolution filter for boosting low intensity values in the separated green channel of an RGB image and suppressing the high values in the same channel. The high values in the green channel become 255 (background) while the nuclei always have low values in the green channel and thus clearly appear as foreground. The proposed technique is tested on 365 images achieving an overall accuracy of 95.89%, while improving the efficiency by 10%. The proposed technique achieved its targets in a realistic way by improving the accuracy as well as the efficiency and both are highly required in the area. PMID:26408877

  10. Imaging leukocytes in vivo with third harmonic generation microscopy

    NASA Astrophysics Data System (ADS)

    Tsai, Cheng-Kun; Chen, Chien-Kuo; Chen, Yu-Shing; Wu, Pei-Chun; Hsieh, Tsung-Yuan; Liu, Han-Wen; Yeh, Chiou-Yueh; Lin, Win-Li; Chia, Jean-San; Liu, Tzu-Ming

    2013-02-01

    Without a labeling, we demonstrated that lipid granules in leukocytes have distinctive third harmonic generation (THG) contrast. Excited by a 1230nm femtosecond laser, THG signals were generated at a significantly higher level in neutrophils than other mononuclear cells, whereas signals in agranular lymphocytes were one order smaller. These characteristic THG features can also be observed in vivo to trace the newly recruited leukocytes following lipopolysaccharide (LPS) challenge. Furthermore, using video-rate THG microscopy, we also captured images of blood cells in human capillaries. Quite different from red-blood-cells, every now and then, round and granule rich blood cells with strong THG contrast appeared in circulation. The corresponding volume densities in blood, evaluated from their frequencies of appearance and the velocity of circulation, fall within the physiological range of human white blood cell counts. These results suggested that labeling-free THG imaging may provide timely tracing of leukocyte movement and hematology inspection without disturbing the normal cellular or physiological status.

  11. Influence of tetracyclines on human polymorphonuclear leukocyte function.

    PubMed Central

    Glette, J; Sandberg, S; Hopen, G; Solberg, C O

    1984-01-01

    Low concentrations of oxytetracycline, doxycycline, or minocycline (less than 10 micrograms/ml) did not influence in vitro polymorphonuclear leukocyte random migration, chemiluminescence, or glucose oxidation. At high concentrations of doxycycline or minocycline (greater than 10 micrograms/ml), chemiluminescence and glucose oxidation were impaired. High concentrations of doxycycline also reduced random migration. Oxytetracycline did not influence these functions in concentrations up to 100 micrograms/ml. The inhibiting effect of doxycycline and minocycline was abolished when 4 mM Mg2+ was added to the reaction mixture, and 4 mM Ca2+ partly restored minocycline-inhibited polymorphonuclear leukocyte functions. This indicates that the major effect of tetracyclines on in vitro polymorphonuclear leukocyte functions is mediated by their divalent cation chelating effect and that the results of in vitro experiments are highly dependent on the concentration of divalent cations in the reaction mixtures. The difference between the tetracyclines may be due to differences in lipid solubility, with solubility being highest for minocycline and lowest for oxytetracycline, or to different divalent cation chelating ability. PMID:6721468

  12. Carbohydrate ligands for endothelial - Leukocyte adhesion molecule 1

    SciTech Connect

    Tiemeyer, M.; Swiedler, S.J.; Ishihara, Masayuki; Moreland, M.; Schweingruber, H.; Hirtzer, P.; Brandley, B.K. )

    1991-02-15

    The acute inflammatory response requires that circulating leukocytes bind to and penetrate the vascular wall to access the site of injury. Several receptors have been implicated in this interaction, including a family of putative carbohydrate-binding proteins. The authors report here the identification of an endogenous carbohydrate ligand for one of these receptors, endothelial-leukocyte adhesion molecule 1 (ELAM-1). Radiolabeled COS cells transfected with a plasmid containing the cDNA for ELAM-1 were used as probes to screen glycolipids extracted from human leukocytes. COS cells transfected with this plasmid adhered to a subset of sialylated glycolipids resolved on TLC plates or adsorbed on polyvinyl chloride microtiter wells. Adhesion to these glycolipids required calcium but was not inhibited by heparin, chondroitin sulfate, keratan sulfate, or yeast phosphomannan. Monosaccharide composition, linkage analysis, and fast atom bombardment mass spectrometry of the glycolipids indicate that the ligands for ELAM-1 are terminally sialylated lactosylceramides with a variable number of N-acetyllactosamine repeats and at least one fucosylated N-acetylglucosamine residue.

  13. Leukocyte trafficking: Can we bring the fight to the tumor?

    PubMed

    Pachynski, Russell; Nazha, Jonathon; Kohrt, Holbrook

    2016-03-01

    Control of leukocyte trafficking plays a critical role in the establishment of effective immune responses. It is now well established that the number or ratio of effector to suppressor immune cells within the tumor microenvironment can significantly impact tumor growth and clinical outcomes. Recently approved immunotherapies by the FDA, and those in development, aim to stimulate effector immune cell function. For example, many checkpoint inhibitors seek to stimulate an immune response to tumors by reversing T-cell exhaustion. However, activation of the immune response outside the tumor microenvironment can lead to sometimes fatal immune-mediated adverse events -- the result of "on-target, off-tumor" effects. Thus, control of localization of these activated effector cells remains a critical component of optimizing tumor response while minimizing immune-mediated adverse events. Chemokines and chemoattractants, along with their receptors on immune cells, govern leukocyte trafficking; thus, understanding their expression pattern in the context of the tumor microenvironment and developing approaches to favorably alter those should lead to improved efficacy of current immunotherapeutics. This review highlights the background of cancer immunotherapy, leukocyte trafficking, and some novel approaches being utilized to optimize recruitment of effector immune cells into the tumor microenvironment. Future combinatorial immunotherapy should incorporate therapeutics aimed at 1) favorably altering the tumor microenvironment, 2) activating effector immune cells, and 3) optimizing effector cell trafficking into tumors. PMID:27115171

  14. Accelerating Dynamic Magnetic Resonance Imaging (MRI) for Lung Tumor Tracking Based on Low-Rank Decomposition in the Spatial–Temporal Domain: A Feasibility Study Based on Simulation and Preliminary Prospective Undersampled MRI

    SciTech Connect

    Sarma, Manoj; Hu, Peng; Rapacchi, Stanislas; Ennis, Daniel; Thomas, Albert; Lee, Percy; Kupelian, Patrick; Sheng, Ke

    2014-03-01

    Purpose: To evaluate a low-rank decomposition method to reconstruct down-sampled k-space data for the purpose of tumor tracking. Methods and Materials: Seven retrospective lung cancer patients were included in the simulation study. The fully-sampled k-space data were first generated from existing 2-dimensional dynamic MR images and then down-sampled by 5 × -20 × before reconstruction using a Cartesian undersampling mask. Two methods, a low-rank decomposition method using combined dynamic MR images (k-t SLR based on sparsity and low-rank penalties) and a total variation (TV) method using individual dynamic MR frames, were used to reconstruct images. The tumor trajectories were derived on the basis of autosegmentation of the resultant images. To further test its feasibility, k-t SLR was used to reconstruct prospective data of a healthy subject. An undersampled balanced steady-state free precession sequence with the same undersampling mask was used to acquire the imaging data. Results: In the simulation study, higher imaging fidelity and low noise levels were achieved with the k-t SLR compared with TV. At 10 × undersampling, the k-t SLR method resulted in an average normalized mean square error <0.05, as opposed to 0.23 by using the TV reconstruction on individual frames. Less than 6% showed tracking errors >1 mm with 10 × down-sampling using k-t SLR, as opposed to 17% using TV. In the prospective study, k-t SLR substantially reduced reconstruction artifacts and retained anatomic details. Conclusions: Magnetic resonance reconstruction using k-t SLR on highly undersampled dynamic MR imaging data results in high image quality useful for tumor tracking. The k-t SLR was superior to TV by better exploiting the intrinsic anatomic coherence of the same patient. The feasibility of k-t SLR was demonstrated by prospective imaging acquisition and reconstruction.

  15. Development of Feedforward Control in a Dynamic Manual Tracking Task

    ERIC Educational Resources Information Center

    van Roon, Dominique; Caeyenberghs, Karen; Swinnen, Stephan P.; Smits-Engelsman, Bouwien C. M.

    2008-01-01

    To examine the development of feedforward control during manual tracking, 117 participants in 5 age groups (6 to 7, 8 to 9, 10 to 11, 12 to 14, and 15 to 17 years) tracked an accelerating dot presented on a monitor by moving an electronic pen on a digitizer. To remain successful at higher target velocities, they had to create a predictive model of…

  16. Fast Track: A Language Arts Program for Middle School Gifted

    ERIC Educational Resources Information Center

    Schneider, Jean

    2008-01-01

    "Fast Track" is a pseudonym for an accelerated, advanced language arts program for verbally gifted and high potential students in grades 6-8. The critical thinking model used for "Fast Track" was gleaned from Coalition of Essential Schools founder Ted Sizer's Habits of Mind: significance, evidence, connections, perspective, and supposition, as…

  17. Plasma accelerator

    DOEpatents

    Wang, Zhehui; Barnes, Cris W.

    2002-01-01

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  18. Accelerated Achievement

    ERIC Educational Resources Information Center

    Ford, William J.

    2010-01-01

    This article focuses on the accelerated associate degree program at Ivy Tech Community College (Indiana) in which low-income students will receive an associate degree in one year. The three-year pilot program is funded by a $2.3 million grant from the Lumina Foundation for Education in Indianapolis and a $270,000 grant from the Indiana Commission…

  19. ACCELERATION INTEGRATOR

    DOEpatents

    Pope, K.E.

    1958-01-01

    This patent relates to an improved acceleration integrator and more particularly to apparatus of this nature which is gyrostabilized. The device may be used to sense the attainment by an airborne vehicle of a predetermined velocitv or distance along a given vector path. In its broad aspects, the acceleration integrator utilizes a magnetized element rotatable driven by a synchronous motor and having a cylin drical flux gap and a restrained eddy- current drag cap deposed to move into the gap. The angular velocity imparted to the rotatable cap shaft is transmitted in a positive manner to the magnetized element through a servo feedback loop. The resultant angular velocity of tae cap is proportional to the acceleration of the housing in this manner and means may be used to measure the velocity and operate switches at a pre-set magnitude. To make the above-described dcvice sensitive to acceleration in only one direction the magnetized element forms the spinning inertia element of a free gyroscope, and the outer housing functions as a gimbal of a gyroscope.

  20. Particle acceleration

    NASA Technical Reports Server (NTRS)

    Vlahos, L.; Machado, M. E.; Ramaty, R.; Murphy, R. J.; Alissandrakis, C.; Bai, T.; Batchelor, D.; Benz, A. O.; Chupp, E.; Ellison, D.

    1986-01-01

    Data is compiled from Solar Maximum Mission and Hinothori satellites, particle detectors in several satellites, ground based instruments, and balloon flights in order to answer fundamental questions relating to: (1) the requirements for the coronal magnetic field structure in the vicinity of the energization source; (2) the height (above the photosphere) of the energization source; (3) the time of energization; (4) transistion between coronal heating and flares; (5) evidence for purely thermal, purely nonthermal and hybrid type flares; (6) the time characteristics of the energization source; (7) whether every flare accelerates protons; (8) the location of the interaction site of the ions and relativistic electrons; (9) the energy spectra for ions and relativistic electrons; (10) the relationship between particles at the Sun and interplanetary space; (11) evidence for more than one acceleration mechanism; (12) whether there is single mechanism that will accelerate particles to all energies and also heat the plasma; and (13) how fast the existing mechanisms accelerate electrons up to several MeV and ions to 1 GeV.

  1. Influence of delivery on numbers of leukocytes, leukocyte subpopulations, and hematopoietic progenitor cells in human umbilical cord blood.

    PubMed

    Lim, F T; van Winsen, L; Willemze, R; Kanhai, H H; Falkenburg, J H

    1994-01-01

    Human umbilical cord blood (UCB) may be used as an alternative source of bone marrow repopulating cells in allogeneic bone marrow transplantation. The quality and quantity of UCB harvests for transplantation is affected by several factors. In this study we analyzed the influence of delivery, in particular stress during delivery, on the numbers of leukocytes and leukocyte subsets in UCB. Four groups of women with different types of deliveries were included in the study, and from each group samples of UCB were analyzed. Blood samples from healthy adults were used as control. In UCB there was a higher absolute number of leukocytes than in peripheral blood (PB). UCB leukocytes were highest after deliveries with a prolonged second stage of labor, which was mainly due to granulocytosis. The percentage of T cells in UCB was lower than in PB, in particular when stress during delivery was higher. In all groups, however, the absolute concentration of T cells per milliliter of UCB was higher than in adult PB. The differences in T cells in stressful deliveries were mainly due to a relative decrease in CD3+/CD4+ cells in UCB. The relative frequency and absolute concentration of the CD56+ cell population in UCB was higher than in PB, which was mostly due to an increase of CD2-/CD56+ cells, in particular in stressful deliveries. The absolute number of CD34+ cells as well as hematopoietic progenitor cells as determined in semisolid medium cultures was high in UCB and was increased in cases of prolonged secondary stage of labor. This study demonstrates that the quality of UCB transplants is influenced by the course of delivery, in particular by stress during delivery. PMID:7749120

  2. Solar tracking system

    DOEpatents

    Okandan, Murat; Nielson, Gregory N.

    2016-07-12

    Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

  3. Compact accelerator

    DOEpatents

    Caporaso, George J.; Sampayan, Stephen E.; Kirbie, Hugh C.

    2007-02-06

    A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

  4. Altered Immunogenicity of Donor Lungs via Removal of Passenger Leukocytes Using Ex Vivo Lung Perfusion.

    PubMed

    Stone, J P; Critchley, W R; Major, T; Rajan, G; Risnes, I; Scott, H; Liao, Q; Wohlfart, B; Sjöberg, T; Yonan, N; Steen, S; Fildes, J E

    2016-01-01

    Passenger leukocyte transfer from the donor lung to the recipient is intrinsically involved in acute rejection. Direct presentation of alloantigen expressed on donor leukocytes is recognized by recipient T cells, promoting acute cellular rejection. We utilized ex vivo lung perfusion (EVLP) to study passenger leukocyte migration from donor lungs into the recipient and to evaluate the effects of donor leukocyte depletion prior to transplantation. For this purpose, female pigs received male left lungs either following 3 h of EVLP or retrieved using standard protocols. Recipients were monitored for 24 h and sequential samples were collected. EVLP-reduced donor leukocyte transfer into the recipient and migration to recipient lymph nodes was markedly reduced. Recipient T cell infiltration of the donor lung was significantly diminished via EVLP. Donor leukocyte removal during EVLP reduces direct allorecognition and T cell priming, diminishing recipient T cell infiltration, the hallmark of acute rejection. PMID:26366523

  5. BICEP's acceleration

    SciTech Connect

    Contaldi, Carlo R.

    2014-10-01

    The recent Bicep2 [1] detection of, what is claimed to be primordial B-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of e-fold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup -3} Mpc {sup -1}. This is in agreement with a previous detection of a suppression in the scalar power [2].

  6. Accurate and efficient spin integration for particle accelerators

    NASA Astrophysics Data System (ADS)

    Abell, Dan T.; Meiser, Dominic; Ranjbar, Vahid H.; Barber, Desmond P.

    2015-02-01

    Accurate spin tracking is a valuable tool for understanding spin dynamics in particle accelerators and can help improve the performance of an accelerator. In this paper, we present a detailed discussion of the integrators in the spin tracking code gpuSpinTrack. We have implemented orbital integrators based on drift-kick, bend-kick, and matrix-kick splits. On top of the orbital integrators, we have implemented various integrators for the spin motion. These integrators use quaternions and Romberg quadratures to accelerate both the computation and the convergence of spin rotations. We evaluate their performance and accuracy in quantitative detail for individual elements as well as for the entire RHIC lattice. We exploit the inherently data-parallel nature of spin tracking to accelerate our algorithms on graphics processing units.

  7. Nanodosimetric track structure in homogeneous extended beams.

    PubMed

    Conte, V; Moro, D; Colautti, P; Grosswendt, B

    2015-09-01

    Physical aspects of particle track structure are important in determining the induction of clustered damage in relevant subcellular structures like the DNA and higher-order genomic structures. The direct measurement of track-structure properties of ionising radiation is feasible today by counting the number of ionisations produced inside a small gas volume. In particular, the so-called track-nanodosimeter, installed at the TANDEM-ALPI accelerator complex of LNL, measures ionisation cluster-size distributions in a simulated subcellular structure of dimensions 20 nm, corresponding approximately to the diameter of the chromatin fibre. The target volume is irradiated by pencil beams of primary particles passing at specified impact parameter. To directly relate these measured track-structure data to radiobiological measurements performed in broad homogeneous particle beams, these data can be integrated over the impact parameter. This procedure was successfully applied to 240 MeV carbon ions and compared with Monte Carlo simulations for extended fields. PMID:25848108

  8. Tracking filter algorithm for automatic video tracking

    NASA Astrophysics Data System (ADS)

    McEver, Mark A.; Kimbrell, James E.

    2006-05-01

    In addition to servo control and power amplification, motion control systems for optical tracking pedestals feature capabilities such as electro-optical tracking using an integrated Automatic Video Tracker (AVT) card. An electro-optical system tracking loop is comprised of sensors mounted on a pointing pedestal, an AVT that detects a target in the sensor imagery, and a tracking filter algorithm that commands the pedestal to follow the target. The tracking filter algorithm receives the target boresight error from the AVT and calculates motion demands for the pedestal servo controller. This paper presents a tracking algorithm based on target state estimation using a Kalman filter. The servo demands are based on calculating the Kalman filter state estimate from absolute line-of-sight angles to the target. Simulations are used to compare its performance to tracking loops without tracking filters, and to other tracking filter algorithms, such as rate feedback loops closed around boresight error. Issues such as data latency and sensor alignment error are discussed.

  9. Leukocyte Populations in Human Preterm and Term Breast Milk Identified by Multicolour Flow Cytometry

    PubMed Central

    Trend, Stephanie; de Jong, Emma; Lloyd, Megan L.; Kok, Chooi Heen; Richmond, Peter; Doherty, Dorota A.; Simmer, Karen; Kakulas, Foteini; Strunk, Tobias; Currie, Andrew

    2015-01-01

    Background Extremely preterm infants are highly susceptible to bacterial infections but breast milk provides some protection. It is unknown if leukocyte numbers and subsets in milk differ between term and preterm breast milk. This study serially characterised leukocyte populations in breast milk of mothers of preterm and term infants using multicolour flow cytometry methods for extended differential leukocyte counts in blood. Methods Sixty mothers of extremely preterm (<28 weeks gestational age), very preterm (28–31 wk), and moderately preterm (32–36 wk), as well as term (37–41 wk) infants were recruited. Colostrum (d2–5), transitional (d8–12) and mature milk (d26–30) samples were collected, cells isolated, and leukocyte subsets analysed using flow cytometry. Results The major CD45+ leukocyte populations circulating in blood were also detectable in breast milk but at different frequencies. Progression of lactation was associated with decreasing CD45+ leukocyte concentration, as well as increases in the relative frequencies of neutrophils and immature granulocytes, and decreases in the relative frequencies of eosinophils, myeloid and B cell precursors, and CD16- monocytes. No differences were observed between preterm and term breast milk in leukocyte concentration, though minor differences between preterm groups in some leukocyte frequencies were observed. Conclusions Flow cytometry is a useful tool to identify and quantify leukocyte subsets in breast milk. The stage of lactation is associated with major changes in milk leukocyte composition in this population. Fresh preterm breast milk is not deficient in leukocytes, but shorter gestation may be associated with minor differences in leukocyte subset frequencies in preterm compared to term breast milk. PMID:26288195

  10. An Incidental Detection of Popliteal Vein Aneurysm during Labeled Leukocyte Scintigraphy

    PubMed Central

    Hassan, H. Abu.; Nazri, M.; Azman, R. R.

    2012-01-01

    Technetium (99mTc) exametazime (hexamethylpropyleneamine oxime, HMPAO) labeled leukocyte scintigraphy is mainly used to exclude occult infection in our institution. On review of previously published article, no case of popliteal venous aneurysm was ever diagnosed and detected on labeled leukocyte scintigraphy. We present a rare case of popliteal venous aneurysm which was detected on labeled leukocyte scintigraphy and was further confirmed with single-photon emission computed tomography and computed tomography fusion. PMID:23372443

  11. Tabletop Experimental Track for Magnetic Launch Assist

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Marshall Space Flight Center's (MSFC's) Advanced Space Transportation Program has developed the Magnetic Launch Assist System, formerly known as the Magnetic Levitation (MagLev) technology that could give a space vehicle a running start to break free from Earth's gravity. A Magnetic Launch Assist system would use magnetic fields to levitate and accelerate a vehicle along a track at speeds up to 600 mph. The vehicle would shift to rocket engines for launch into orbit. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, a Magnetic Launch Assist system would electromagnetically propel a space vehicle along the track. The tabletop experimental track for the system shown in this photograph is 44-feet long, with 22-feet of powered acceleration and 22-feet of passive braking. A 10-pound carrier with permanent magnets on its sides swiftly glides by copper coils, producing a levitation force. The track uses a linear synchronous motor, which means the track is synchronized to turn the coils on just before the carrier comes in contact with them, and off once the carrier passes. Sensors are positioned on the side of the track to determine the carrier's position so the appropriate drive coils can be energized. MSFC engineers have conducted tests on the indoor track and a 50-foot outdoor track. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

  12. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  13. Imaging of Leukocyte Trafficking in Alzheimer’s Disease

    PubMed Central

    Pietronigro, Enrica; Zenaro, Elena; Constantin, Gabriela

    2016-01-01

    Alzheimer’s disease (AD) is the most common neurodegenerative disorder and is characterized by a progressive decline of cognitive functions. The neuropathological features of AD include amyloid beta (Aβ) deposition, intracellular neurofibrillary tangles derived from the cytoskeletal hyperphosphorylated tau protein, amyloid angiopathy, the loss of synapses, and neuronal degeneration. In the last decade, inflammation has emerged as a key feature of AD, but most studies have focused on the role of microglia-driven neuroinflammation mechanisms. A dysfunctional blood–brain barrier has also been implicated in the pathogenesis of AD, and several studies have demonstrated that the vascular deposition of Aβ induces the expression of adhesion molecules and alters the expression of tight junction proteins, potentially facilitating the transmigration of circulating leukocytes. Two-photon laser scanning microscopy (TPLSM) has become an indispensable tool to dissect the molecular mechanisms controlling leukocyte trafficking in the central nervous system (CNS). Recent TPLSM studies have shown that vascular deposition of Aβ in the CNS promotes intraluminal neutrophil adhesion and crawling on the brain endothelium and also that neutrophils extravasate in the parenchyma preferentially in areas with Aβ deposits. These studies have also highlighted a role for LFA-1 integrin in neutrophil accumulation in the CNS of AD-like disease models, revealing that LFA-1 inhibition reduces the corresponding cognitive deficit and AD neuropathology. In this article, we consider how current imaging techniques can help to unravel new inflammation mechanisms in the pathogenesis of AD and identify novel therapeutic strategies to treat the disease by interfering with leukocyte trafficking mechanisms. PMID:26913031

  14. Phosphorylation of leukocyte PECAM and its association with detergent-resistant membranes regulate transendothelial migration.

    PubMed

    Florey, Oliver; Durgan, Joanne; Muller, William

    2010-08-01

    Leukocyte migration across the endothelial lining is a critical step in the body's response to infection and inflammation. The homophilic interaction between endothelial PECAM and leukocyte PECAM is essential for this process. The molecular events that are triggered in the endothelial cell by PECAM engagement have been well characterized; however, the function of leukocyte PECAM remains to be elucidated. To study this, we first blocked leukocyte transmigration using anti-PECAM Ab and then specifically activated leukocyte PECAM. This was sufficient to overcome the block and promote transmigration, suggesting an active signaling role for leukocyte PECAM. Consistent with this, we found that ligation of leukocyte PECAM induces phosphorylation of two tyrosine residues on its cytoplasmic tail. By performing RNA interference-rescue experiments, we demonstrate that these phosphorylation events are indispensable for transendothelial migration. Finally, we show that leukocyte PECAM translocates to a detergent-resistant membrane (DRM) during transmigration. PECAM localized in DRMs displays reduced phosphorylation and does not support transmigration. Together, these data support a model whereby engagement of leukocyte PECAM induces its transient tyrosine phosphorylation and induction of downstream signals that drive transmigration. These signals are then downregulated following PECAM translocation to DRMs. PMID:20581150

  15. Kinetics of reversible-sequestration of leukocytes by the isolated perfused rat lung

    SciTech Connect

    Goliaei, B.

    1980-08-01

    The kinetics and morphology of sequestration and margination of rat leukocytes were studied using an isolated perfused and ventilated rat lung preparation. Whole rat blood, bone marrow suspension, or leukocyte suspensions, were used to perfuse the isolated rat lung. The lung was also perfused with latex particle suspensions and the passage of particles through the lung capillaries was studied. When a leukocyte suspension was perfused through the lung in the single-pass mode, the rate of sequestration decreased as more cells were perfused. In contrast, latex particles of a size comparable to that of leukocytes were totally stopped by the lung. When the leukocyte suspension was recirculated through the lung, cells were rapidly removed from circulation until a steady state was reached, after which no net removal of cells by the lung occurred. These results indicate that leukocytes are reversibly sequestered from circulation. The sequestered cells marginated and attached to the luminal surface of the endothelium of post-capillary venules and veins. A mathematical model was developed based on the assumption that the attachment and detachment of leukocytes to blood vessel walls follows first-order kinetics. The model correctly predicts the following characteristics of the system: (a) the kinetics of the sequestration of leukocytes by the lung; (b) the existence of a steady state when a suspension of leukocytes is recirculated through the lung; and (c) the independence of the fraction of cells remaining in circulation from the starting concentration for all values of starting concentration. (ERB)

  16. BK Nephritis and Venous Thrombosis in Renal Transplant Recipient Detected by 111In Leukocyte Imaging.

    PubMed

    Pucar, Darko; Klein, Kandace; Corley, James; Williams, Hadyn T

    2015-07-01

    Three months after deceased donor kidney transplant, a patient who presented with proteinuric renal dysfunction and fever of undetermined origin was found to have BK viruria by quantitative polymerase chain reaction analysis. An ¹¹¹In leukocyte scan showed increased renal transplant uptake consistent with nephritis and linear uptake in the knee. Venous duplex ultrasound revealed acute occlusive thrombosis in the superficial right lesser saphenous vein in the area of increased radiolabeled leukocyte uptake. This ¹¹¹In leukocyte scan performed for fever of undetermined origin demonstrated findings of BK nephritis in a renal transplant patient and associated acute venous thrombosis related to leukocyte colonization. PMID:26018698

  17. The Study of Leukocyte Functions in a Rotating Wall Vessel

    NASA Technical Reports Server (NTRS)

    Trial, JoAnn

    1998-01-01

    The objective of this study was to investigate the behavior of leukocytes under free-fall conditions in a rotating wall vessel. In such a vessel, the tendency of a cell to fall in response to gravity is opposed by the rotation of the vessel and the culture medium within, keeping the cells in suspension without fluid shear. Previous reports indicated that such functions as lymphocyte migration through collagen matrix or monocyte cytokine secretion are altered under these conditions, and these changes correlate with similar functional defects of cultured cells seen during spaceflight.

  18. Longitudinal evaluation of leukocyte transcripts in killer whales (Orcinus Orca)

    USGS Publications Warehouse

    Sitt, Tatjana; Bowen, Lizabeth; Lee, Chia-Shan; Blanchard, Myra; McBain, James; Dold, Christopher; Stott, Jeffrey L.

    2016-01-01

    Early identification of illness and/or presence of environmental and/or social stressors in free-ranging and domestic cetaceans is a priority for marine mammal health care professionals. Incorporation of leukocyte gene transcript analysis into the diagnostic tool kit has the potential to augment classical diagnostics based upon ease of sample storage and shipment, inducible nature and well-defined roles of transcription and associated downstream actions. Development of biomarkers that could serve to identify “insults” and potentially differentiate disease etiology would be of great diagnostic value. To this end, a modest number of peripheral blood leukocyte gene transcripts were selected for application to a domestic killer whale population with a focus on broad representation of inducible immunologically relevant genes. Normalized leukocyte transcript values, longitudinally acquired from 232 blood samples derived from 26 clinically healthy whales, were not visibly influenced temporally nor by sex or the specific Park in which they resided. Stability in leukocyte transcript number during periods of health enhances their potential use in diagnostics through identification of outliers. Transcript levels of two cytokine genes, IL-4 and IL-17, were highly variable within the group as compared to the other transcripts. IL-4 transcripts were typically absent. Analysis of transcript levels on the other genes of interest, on an individual animal basis, identified more outliers than were visible when analyzed in the context of the entire population. The majority of outliers (9 samples) were low, though elevated transcripts were identified for IL-17 from 2 animals and one each for Cox-2 and IL-10. The low number of outliers was not unexpected as sample selection was intentionally directed towards animals that were clinically healthy at the time of collection. Outliers may reflect animals experiencing subclinical disease that is transient and self-limiting. The

  19. Longitudinal evaluation of leukocyte transcripts in killer whales (Orcinus Orca).

    PubMed

    Sitt, Tatjana; Bowen, Lizabeth; Lee, Chia-Shan; Blanchard, Myra T; McBain, James; Dold, Christopher; Stott, Jeffrey L

    2016-07-01

    Early identification of illness and/or presence of environmental and/or social stressors in free-ranging and domestic cetaceans is a priority for marine mammal health care professionals. Incorporation of leukocyte gene transcript analysis into the diagnostic tool kit has the potential to augment classical diagnostics based upon ease of sample storage and shipment, inducible nature and well-defined roles of transcription and associated downstream actions. Development of biomarkers that could serve to identify "insults" and potentially differentiate disease etiology would be of great diagnostic value. To this end, a modest number of peripheral blood leukocyte gene transcripts were selected for application to a domestic killer whale population with a focus on broad representation of inducible immunologically relevant genes. Normalized leukocyte transcript values, longitudinally acquired from 232 blood samples derived from 26 clinically healthy whales, were not visibly influenced temporally nor by sex or the specific Park in which they resided. Stability in leukocyte transcript number during periods of health enhances their potential use in diagnostics through identification of outliers. Transcript levels of two cytokine genes, IL-4 and IL-17, were highly variable within the group as compared to the other transcripts. IL-4 transcripts were typically absent. Analysis of transcript levels on the other genes of interest, on an individual animal basis, identified more outliers than were visible when analyzed in the context of the entire population. The majority of outliers (9 samples) were low, though elevated transcripts were identified for IL-17 from 2 animals and one each for Cox-2 and IL-10. The low number of outliers was not unexpected as sample selection was intentionally directed towards animals that were clinically healthy at the time of collection. Outliers may reflect animals experiencing subclinical disease that is transient and self-limiting. The immunologic

  20. Theileria-transformed bovine leukocytes have cancer hallmarks.

    PubMed

    Tretina, Kyle; Gotia, Hanzel T; Mann, David J; Silva, Joana C

    2015-07-01

    The genus Theileria includes tick-transmitted apicomplexan parasites of ruminants with substantial economic impact in endemic countries. Some species, including Theileria parva and Theileria annulata, infect leukocytes where they induce phenotypes that are shared with some cancers, most notably immortalization, hyperproliferation, and dissemination. Despite considerable research into the affected host signaling pathways, the parasite proteins directly responsible for these host phenotypes remain unknown. In this review we outline current knowledge on the manipulation of host cells by transformation-inducing Theileria, and we propose that comparisons between cancer biology and host-Theileria interactions can reveal chemotherapeutic targets against Theileria-induced pathogenesis based on cancer treatment approaches. PMID:25951781

  1. Accelerators and the Accelerator Community

    SciTech Connect

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  2. The advanced position compensation to improve the dynamic tracking ability for fast moving target in an optoelectronic tracking system

    NASA Astrophysics Data System (ADS)

    Wu, Nengwei; Zhao, Lirong; Zhou, Hui; Chen, Juan

    2005-12-01

    The servo control system of the optoelectronic tracking equipment usually is a kind of SISO. When the fast moving target is tracked, the over-tune of the servo system is the main representation for the dynamic tracking error. As the result, the tracking ability may be improved by limiting the over-tune. We put forward a method, the advanced position compensation (called as APC in short), which is to check the speed-overtune by applying the advanced position information. For the large accelerate target, small over-tune tracking is achieved, but it lowers the ability for tracking the sine signal at low frequency area. While the dynamic high-type can improve the tracking precision for the sine signal at low frequency area, we work out a brand-new method, which combines the advantages of the both. It increases the tracking precision in the whole frequency band at large scale for the optoelectronic tracking system. The simulation results show that when the target moves with the largest accelerate 120°/s2, 120°/s, the maximum static tracking error is about 0.6".

  3. To Track or Not to Track?

    ERIC Educational Resources Information Center

    Hesson, Heather

    2010-01-01

    Background: This paper was written for a graduate level action research course at Muskingum University, located in New Concord, OH. Purpose: The purpose of this research was to determine which method of instruction best serves ALL high school students. Is it more advantageous to track ("ability group") students or not to track students in high…

  4. Calculating track thrust with track functions

    NASA Astrophysics Data System (ADS)

    Chang, Hsi-Ming; Procura, Massimiliano; Thaler, Jesse; Waalewijn, Wouter J.

    2013-08-01

    In e+e- event shapes studies at LEP, two different measurements were sometimes performed: a “calorimetric” measurement using both charged and neutral particles and a “track-based” measurement using just charged particles. Whereas calorimetric measurements are infrared and collinear safe, and therefore calculable in perturbative QCD, track-based measurements necessarily depend on nonperturbative hadronization effects. On the other hand, track-based measurements typically have smaller experimental uncertainties. In this paper, we present the first calculation of the event shape “track thrust” and compare to measurements performed at ALEPH and DELPHI. This calculation is made possible through the recently developed formalism of track functions, which are nonperturbative objects describing how energetic partons fragment into charged hadrons. By incorporating track functions into soft-collinear effective theory, we calculate the distribution for track thrust with next-to-leading logarithmic resummation. Due to a partial cancellation between nonperturbative parameters, the distributions for calorimeter thrust and track thrust are remarkably similar, a feature also seen in LEP data.

  5. Measuring residual accelerations in the Spacelab environment

    NASA Technical Reports Server (NTRS)

    Witherow, William K.

    1991-01-01

    A triglycine sulfate (TGS) crystal growth experiment carried out in Spacelab 3 flown onboard the Shuttle orbiter in 1985 is described. The TGS experiment was aimed at examining diffusion limited crystal growth by minimizing convection in the microgravity environment of the Spacelab. During the experiment tiny crystals were found floating free in the growth solution. Since the free crystals were in a viscous fluid, the 'noise' accelerations of the Shuttle were damped out. This made it possible to measure the constant gravitational acceleration by tracking the positions of these crystals. The velocities and accelerations obtained by these measurements are presented.

  6. Security market reaction to FDA fast track designations.

    PubMed

    Anderson, Christopher W; Zhang, Ying

    2010-01-01

    Pharmaceutical firms can apply for the Food and Drug Administration to 'fast track' research and de velopment on new drugs, accelerating clinical trials and expediting regulatory review required prior to marketing to consumers. We investigate security market reaction to more than 100 fast track designations from 1998 to 2004. Fast track designation appears to enhance investor recognition of firm value. Specifically, fast track designation coincides with abnormal trading volume and excess daily stock returns for sponsoring firms. Institutional ownership and analyst attention also increase. Market response is more pronounced for firms that are smaller, do not yet market products, and have low institutional ownership. PMID:21294437

  7. Discrimination, mental health, and leukocyte telomere length among African American men.

    PubMed

    Chae, David H; Epel, Elissa S; Nuru-Jeter, Amani M; Lincoln, Karen D; Taylor, Robert Joseph; Lin, Jue; Blackburn, Elizabeth H; Thomas, Stephen B

    2016-01-01

    African American men in the US experience disparities across multiple health outcomes. A common mechanism underlying premature declines in health may be accelerated biological aging, as reflected by leukocyte telomere length (LTL). Racial discrimination, a qualitatively unique source of social stress reported by African American men, in tandem with poor mental health, may negatively impact LTL in this population. The current study examined cross-sectional associations between LTL, self-reported racial discrimination, and symptoms of depression and anxiety among 92 African American men 30-50 years of age. LTL was measured in kilobase pairs using quantitative polymerase chain reaction assay. Controlling for sociodemographic factors, greater anxiety symptoms were associated with shorter LTL (b=-0.029, standard error [SE]=0.014; p<0.05). There were no main effects of racial discrimination or depressive symptoms on LTL, but we found evidence for a significant interaction between the two (b=0.011, SE=0.005; p<0.05). Racial discrimination was associated with shorter LTL among those with lower levels of depressive symptoms. Findings from this study highlight the role of social stressors and individual-level psychological factors for physiologic deterioration among African American men. Consistent with research on other populations, greater anxiety may reflect elevated stress associated with shorter LTL. Racial discrimination may represent an additional source of social stress among African American men that has detrimental consequences for cellular aging among those with lower levels of depression. PMID:26398001

  8. PSYCHIATRIC DISORDERS AND LEUKOCYTE TELOMERE LENGTH: UNDERLYING MECHANISMS LINKING MENTAL ILLNESS WITH CELLULAR AGING

    PubMed Central

    Lindqvist, Daniel; Epel, Elissa S.; Mellon, Synthia H.; Penninx, Brenda W.; Révész, Dóra; Verhoeven, Josine E.; Reus, Victor I.; Lin, Jue; Mahan, Laura; Hough, Christina M.; Rosser, Rebecca; Bersani, F. Saverio; Blackburn, Elizabeth H.; Wolkowitz, Owen M.

    2015-01-01

    Many psychiatric illnesses are associated with early mortality and with an increased risk of developing physical diseases that are more typically seen in the elderly. Moreover, certain psychiatric illnesses may be associated with accelerated cellular aging, evidenced by shortened leukocyte telomere length (LTL), which could underlie this association. Shortened LTL reflects a cell’s mitotic history and cumulative exposure to inflammation and oxidation as well as the availability of telomerase, a telomere-lengthening enzyme. Critically short telomeres can cause cells to undergo senescence, apoptosis or genomic instability, and shorter LTL correlates with poorer health and predicts mortality. Emerging data suggest that LTL may be reduced in certain psychiatric illnesses, perhaps in proportion to exposure to the psychiatric illnesses, although conflicting data exist. Telomerase has been less well characterized in psychiatric illnesses, but a role in depression and in antidepressant and neurotrophic effects has been suggested by preclinical and clinical studies. In this article, studies on LTL and telomerase activity in psychiatric illnesses are critically reviewed, potential mediators are discussed, and future directions are suggested. A deeper understanding of cellular aging in psychiatric illnesses could lead to re-conceptualizing them as systemic illnesses with manifestations inside and outside the brain and could identify new treatment targets. PMID:25999120

  9. Psychiatric disorders and leukocyte telomere length: Underlying mechanisms linking mental illness with cellular aging.

    PubMed

    Lindqvist, Daniel; Epel, Elissa S; Mellon, Synthia H; Penninx, Brenda W; Révész, Dóra; Verhoeven, Josine E; Reus, Victor I; Lin, Jue; Mahan, Laura; Hough, Christina M; Rosser, Rebecca; Bersani, F Saverio; Blackburn, Elizabeth H; Wolkowitz, Owen M

    2015-08-01

    Many psychiatric illnesses are associated with early mortality and with an increased risk of developing physical diseases that are more typically seen in the elderly. Moreover, certain psychiatric illnesses may be associated with accelerated cellular aging, evidenced by shortened leukocyte telomere length (LTL), which could underlie this association. Shortened LTL reflects a cell's mitotic history and cumulative exposure to inflammation and oxidation as well as the availability of telomerase, a telomere-lengthening enzyme. Critically short telomeres can cause cells to undergo senescence, apoptosis or genomic instability, and shorter LTL correlates with poorer health and predicts mortality. Emerging data suggest that LTL may be reduced in certain psychiatric illnesses, perhaps in proportion to exposure to the psychiatric illnesses, although conflicting data exist. Telomerase has been less well characterized in psychiatric illnesses, but a role in depression and in antidepressant and neurotrophic effects has been suggested by preclinical and clinical studies. In this article, studies on LTL and telomerase activity in psychiatric illnesses are critically reviewed, potential mediators are discussed, and future directions are suggested. A deeper understanding of cellular aging in psychiatric illnesses could lead to re-conceptualizing them as systemic illnesses with manifestations inside and outside the brain and could identify new treatment targets. PMID:25999120

  10. Leukocyte Responsiveness to Exercise in Individuals Positive for Human Cytomegalovirus.

    PubMed

    Wilson, J N; Navalta, J W

    2016-05-01

    Human cytomegalovirus (HCMV) infects 50% of adults in the United States. HCMV can become a cause for concern in individuals who have a compromised immune system, which may occur after high-intensity exercise. The purpose of this preliminary study was to characterize the lymphocyte, monocyte, and neutrophil responses to exercise in HCMV+individuals. Participants were either positive (HCMV +) or negative (HCMV-) for HCMV. Participants visited the laboratory on 3 separate occasions: HCMV screening, 100% VO2max test, and 80% VO2max run. Mixed-model factorial ANOVA procedures with repeated measures on sampling condition were performed on absolute and relative circulating lymphocytes, monocytes, and neutrophils. Significant main effects for time for both absolute and relative values were seen for all leukocyte subsets regardless of virus status. Significant differences for absolute and relative values were seen between sampling conditions for all leukocyte subsets. We report for the first time that HCMV status does not affect circulating neutrophil responses to high-intensity exercise, though exercise-induced neutrocytosis is seen during the post-exercise and 60 min post-exercise sampling conditions, regardless of HCMV status. There is no HCMV effect on circulating monocyte responses to exercise, though exercise-induced monocytosis was seen during the post-exercise sampling condition regardless of HCMV status. PMID:26837931

  11. The history of fever, leukocytic pyrogen and interleukin-1

    PubMed Central

    Dinarello, Charles A

    2015-01-01

    There has been great progress in the 30 y since the reporting in 1984 of the cDNA for interleukin1 (IL1) β in the human and IL1α in the mouse. However, the history of IL1 begins in the early 1940s with investigations into the nature of an endogenous fever-producing protein released rabbit peritoneal neutrophils. Most researchers in immunology today are unaware that the field of cytokines, particularly the field of inflammatory cytokines. Toll-like receptors and innate immunity traces back to studies on fever. Researchers in infectious diseases wanted to know about an endogenous protein that caused fever, independent of infection. The endogenous fever-producing protein was called by various names: granulocyte, endogenous or leukocytic pyrogen. It is a fascinating and sometimes controversial story for biology and medicine and for the treatment of inflammatory diseases. Few imagined that this fever-producing protein would play such a major role in nearly every cell and in most diseases. This paper reviews the true background and milestones of interleukin1 from the purification of leukocytic pyrogen to the first cDNA of IL1β and the validation of cytokine biology from ill-defined factors to its present day importance.

  12. Electromagnetic wave emitting products and "Kikoh" potentiate human leukocyte functions.

    PubMed

    Niwa, Y; Iizawa, O; Ishimoto, K; Jiang, X; Kanoh, T

    1993-09-01

    Tourmaline (electric stone, a type of granite stone), common granite stone, ceramic disks, hot spring water and human palmar energy (called "Kikoh" in Japan and China), all which emit electromagnetic radiation in the far infrared region (wavelength 4-14 microns). These materials were thus examined for effects on human leukocyte activity and on lipid peroxidation of unsaturated fatty acids. It was revealed that these materials significantly increased intracellular calcium ion concentration, phagocytosis, and generation of reactive oxygen species in neutrophils, and the blastogenetic response of lymphocytes to mitogens. Chemotactic activity by neutrophils was also enhanced by exposure to tourmaline and the palm of "Kikohshi" i.e., a person who heals professionally by the laying on of hands. Despite the increase in reactive oxygen species generated by neutrophils, lipid peroxidation from unsaturated fatty acid was markedly inhibited by these four materials. The results suggest that materials emitting electromagnetic radiation in the far infrared range, which are widely used in Japan for cosmetic, therapeutic, and preservative purposes, appear capable of potentiating leukocyte functions without promoting oxidative injury. PMID:8406976

  13. Leukocyte subsets and neutrophil function after short-term spaceflight

    NASA Technical Reports Server (NTRS)

    Stowe, R. P.; Sams, C. F.; Mehta, S. K.; Kaur, I.; Jones, M. L.; Feeback, D. L.; Pierson, D. L.

    1999-01-01

    Changes in leukocyte subpopulations and function after spaceflight have been observed but the mechanisms underlying these changes are not well defined. This study investigated the effects of short-term spaceflight (8-15 days) on circulating leukocyte subsets, stress hormones, immunoglobulin levels, and neutrophil function. At landing, a 1.5-fold increase in neutrophils was observed compared with preflight values; lymphocytes were slightly decreased, whereas the results were variable for monocytes. No significant changes were observed in plasma levels of immunoglobulins, cortisol, or adrenocorticotropic hormone. In contrast, urinary epinephrine, norepinephrine, and cortisol were significantly elevated at landing. Band neutrophils were observed in 9 of 16 astronauts. Neutrophil chemotactic assays showed a 10-fold decrease in the optimal dose response after landing. Neutrophil adhesion to endothelial cells was increased both before and after spaceflight. At landing, the expression of MAC-1 was significantly decreased while L-selectin was significantly increased. These functional alterations may be of clinical significance on long-duration space missions.

  14. Early and delayed indium 111 leukocyte imaging in Crohn's disease

    SciTech Connect

    Navab, F.; Boyd, C.M.; Diner, W.C.; Subramani, R.; Chan, C.

    1987-10-01

    Twenty-seven patients with Crohn's disease were studied for the presence and location of activity by both early (4 h) and delayed (18-24 h) indium 111 leukocyte imaging. The results were compared with other parameters of disease activity including Crohn's disease activity index, barium studies, and endoscopy. There was a correlation between early images and Crohn's disease activity index (r = 0.78) and between delayed images and index (r = 0.82). Based upon the corresponding Crohn's disease activity index, the sensitivity of early and delayed imaging was 81.0% and 95.2%, respectively. Specificity of early and delayed imaging was 75.0% and 87.0%, respectively. Presence of activity on the early and delayed imaging agreed with activity on barium studies and colonoscopy in approximately 80% of cases. Correlation of location of disease by leukocyte imaging and x-ray was observed in 58.9% of early scans and 55.0% of delayed scans. Correlation of the location of disease by imaging and endoscopy was observed in 71.4% of early and 75.0% of delayed studies. Because of the possibility of occurrence of false-negative results in early images, delayed imaging should always be included in evaluation of disease activity in patients with Crohn's disease who are suspected of having mild activity. Delayed imaging is not required if the early imaging study clearly shows activity.

  15. Modulation of Leukocyte Behavior by an Inflamed Extracellular Matrix

    PubMed Central

    Schor, Hagai; Vaday, Gayle G.

    2000-01-01

    Inflammation is a response of the immune system to foreign insult or physical damage. Various cellular and humoral components of the immune system are recruited from the vascular system and are translocated through endothelium, and into extracellular matrix (ECM) compartments of inflamed tissues. This translocation is orchestrated by various types of accessory signals, in the form of soluble or complexed molecules, which evoke remarkable transitions in leukocyte activities. Recruited inflammatory cells give rise to mechanisms of migration, including the secretion of enzymes and other pro-inflammatory mediators and the alteration of their adhesive contacts with the ECM. Hence, migrating cells secrete enzymes, chemokines, and cytokines which interact with the ECM, and thereby, provide the cells with intrinsic signals for coordinating their responses. Resultant products of enzymatic modifications to the ECM microenvironment, such as cytokine- and ECM-derived molecules, may be also part of a cell-signaling mechanism that provides leukocytes with information about the nature of their inflammatory activity; such a mechanism may give the immune system data that can be cognitively interpreted for consequential activities. This article reviews the findings that support this notion and describe the dynamic interactions between participants of the inflammatory processes. PMID:11097214

  16. Interactions between CD44 and Hyaluronan in Leukocyte Trafficking

    PubMed Central

    McDonald, Braedon; Kubes, Paul

    2015-01-01

    Recruitment of leukocytes from the bloodstream to inflamed tissues requires a carefully regulated cascade of binding interactions between adhesion molecules on leukocytes and endothelial cells. Adhesive interactions between CD44 and hyaluronan (HA) have been implicated in the regulation of immune cell trafficking within various tissues. In this review, the biology of CD44–HA interactions in cell trafficking is summarized, with special attention to neutrophil recruitment within the liver microcirculation. We describe the molecular mechanisms that regulate adhesion between neutrophil CD44 and endothelial HA, including recent evidence implicating serum-derived hyaluronan-associated protein as an important co-factor in the binding of HA to CD44 under flow conditions. CD44–HA-mediated neutrophil recruitment has been shown to contribute to innate immune responses to invading microbes, as well as to the pathogenesis of many inflammatory diseases, including various liver pathologies. As a result, blockade of neutrophil recruitment by targeting CD44–HA interactions has proven beneficial as an anti-inflammatory treatment strategy in a number of animal models of inflammatory diseases. PMID:25741341

  17. Indium-/sup 111/ leukocyte imaging in appendicitis

    SciTech Connect

    Navarro, D.A.; Weber, P.M.; Kang, I.Y.; dos Remedios, L.V.; Jasko, I.A.; Sawicki, J.E.

    1987-04-01

    Indium-/sup 111/-labeled leukocyte scintigraphy was applied to the diagnosis of acute appendicitis. Thirty-two patients observed in the hospital for possible appendicitis were prospectively studied. Scanning was done 2 hr after radiopharmaceutical injection. Thirteen scans were positive for acute appendicitis, and all but one were confirmed at laparotomy. In addition, two cases of colitis and two cases of peritonitis were detected. Of 15 negative studies, 11 had a benign course. Four patients with negative studies had laparotomy; two were found to have appendicitis and two had a normal appendix. Of 14 proven cases of appendicitis, 12 scans were positive for appendicitis with one false-positive scan, providing a sensitivity of 86%. Specificity was 93%: all negative cases except one had negative scans. Overall accuracy was 91% (29 of 32), comparing favorably with the accepted false-positive laparotomy rate of 25%. Use of In-/sup 111/-labeled leukocyte scintigraphy serves to reduce the false-positive laparotomy rate and to shorten the clinical observation time in patients with acute appendicitis.

  18. Leukocyte responses to immobilized patterns of CXCL8.

    PubMed

    Girrbach, Maria; Rink, Ina; Ladnorg, Tatjana; Azucena, Carlos; Heißler, Stefan; Haraszti, Tamás; Schepers, Ute; Schmitz, Katja

    2016-06-01

    The attachment of neutrophils to the endothelial surface and their migration towards the site of inflammation following chemokine gradients play an essential role in the innate immune response. Chemokines adhere to glycosaminoglycans on the endothelial surface to be detected by leukocytes and trigger their movement along surface- bound gradients in a process called haptotaxis. In assays to systematically study the response of leukocytes to surface-bound compounds both the spatial arrangement of the compound as well as the mode of immobilization need to be controlled. In this study microcontact printing was employed to create patterns of hydrophobic or functionalized thiols on gold-coated glass slides and CXCL8 was immobilized on the thiol coated areas using three different strategies. Human neutrophils adhered to the CXCL8-coated lines but not to the PEG-coated background. We could show that more cells adhered to CXCL8 adsorbed to hydrophobic octadecanethiol than on CXCL8 covalently bound to amino undecanethiol or CXCL8 specifically bound to immobilized heparin on aminothiol. Likewise general cell activity such as lamellipodia formation and random migration were most pronounced for CXCL8 adsorbed on a hydrophobic surface which may be attributed to the larger amounts of protein immobilized on this type of surface. PMID:26970827

  19. Mononuclear Leukocyte Infiltrate in Extraplacental Membranes and Preterm Delivery

    PubMed Central

    Holzman, Claudia; Senagore, Patricia K.; Wang, Jianling

    2013-01-01

    Large numbers of polymorphonuclear leukocytes in the amnion and chorion define histological chorioamnionitis (HCA), a condition linked to spontaneous preterm delivery (PTD). Less is known about placental patterns of mononuclear leukocyte (MNL) density and PTD. In this prospective study (1998–2004), women were sampled from 52 clinics in 5 Michigan communities and enrolled at 16–27 weeks’ gestation. HCA and MNL distributions in delivered placentas were evaluated microscopically in a subcohort (290 preterm, 823 term). Midpregnancy biomarkers from maternal blood (i.e., C-reactive protein (CRP), corticotropin-releasing hormone, and cytokines) were compared among term and PTD subjects grouped by presence/absence of HCA and high MNL density. A density of more than 10 MNLs per high-power field in the chorion of the membrane roll, referred to as MNL-CMR, was associated with medically indicated PTD (odds ratio = 2.2, 95% confidence interval: 1.3, 3.6) and spontaneous PTD (odds ratio = 2.5, 95% confidence interval: 1.7, 3.7). Associations persisted after removal of women with HCA-positive placentas, abruption, hypertensive disorders, or obesity. HCA-associated PTD showed higher CRP and cytokine levels. MNL-CMR-associated PTD showed higher CRP and corticotropin-releasing hormone levels. These data suggest that an MNL infiltrate in the chorion of the membrane roll marks PTD pathways that are distinct from HCA and not entirely explained by pregnancy complications. PMID:23429723

  20. GPU COMPUTING FOR PARTICLE TRACKING

    SciTech Connect

    Nishimura, Hiroshi; Song, Kai; Muriki, Krishna; Sun, Changchun; James, Susan; Qin, Yong

    2011-03-25

    This is a feasibility study of using a modern Graphics Processing Unit (GPU) to parallelize the accelerator particle tracking code. To demonstrate the massive parallelization features provided by GPU computing, a simplified TracyGPU program is developed for dynamic aperture calculation. Performances, issues, and challenges from introducing GPU are also discussed. General purpose Computation on Graphics Processing Units (GPGPU) bring massive parallel computing capabilities to numerical calculation. However, the unique architecture of GPU requires a comprehensive understanding of the hardware and programming model to be able to well optimize existing applications. In the field of accelerator physics, the dynamic aperture calculation of a storage ring, which is often the most time consuming part of the accelerator modeling and simulation, can benefit from GPU due to its embarrassingly parallel feature, which fits well with the GPU programming model. In this paper, we use the Tesla C2050 GPU which consists of 14 multi-processois (MP) with 32 cores on each MP, therefore a total of 448 cores, to host thousands ot threads dynamically. Thread is a logical execution unit of the program on GPU. In the GPU programming model, threads are grouped into a collection of blocks Within each block, multiple threads share the same code, and up to 48 KB of shared memory. Multiple thread blocks form a grid, which is executed as a GPU kernel. A simplified code that is a subset of Tracy++ [2] is developed to demonstrate the possibility of using GPU to speed up the dynamic aperture calculation by having each thread track a particle.

  1. Photographing Track Meets.

    ERIC Educational Resources Information Center

    Palmer, Erik

    2001-01-01

    Argues that the sport of track and field, because of the sport itself and its relatively easy access to photographers, is an obvious target for cameras. Discusses rules of the track that photographers must follow; picking a location; and equipment. Discusses shooting four specific track and field events and offers behind the scenes photos. (SR)

  2. Solar tracking apparatus

    DOEpatents

    Hammons, Burrell E.

    1980-01-01

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxiliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  3. Solar tracking apparatus

    DOEpatents

    Hammons, B.E.

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxilliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  4. Track and Field Facilities.

    ERIC Educational Resources Information Center

    Wood, Tony

    2001-01-01

    Discusses planning and design tips that help ensure track and field facilities are successful and well-suited to both school and community use. Examines approaches to determining the best track surface and ways to maximize track and field flexibility with limited space. (GR)

  5. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  6. Attention's Accelerator.

    PubMed

    Reinhart, Robert M G; McClenahan, Laura J; Woodman, Geoffrey F

    2016-06-01

    How do people get attention to operate at peak efficiency in high-pressure situations? We tested the hypothesis that the general mechanism that allows this is the maintenance of multiple target representations in working and long-term memory. We recorded subjects' event-related potentials (ERPs) indexing the working memory and long-term memory representations used to control attention while performing visual search. We found that subjects used both types of memories to control attention when they performed the visual search task with a large reward at stake, or when they were cued to respond as fast as possible. However, under normal circumstances, one type of target memory was sufficient for slower task performance. The use of multiple types of memory representations appears to provide converging top-down control of attention, allowing people to step on the attentional accelerator in a variety of high-pressure situations. PMID:27056975

  7. Beneficial effects of secretory leukocyte protease inhibitor after spinal cord injury

    PubMed Central

    Ghasemlou, Nader; Bouhy, Delphine; Yang, Jingxuan; López-Vales, Rubèn; Haber, Michael; Thuraisingam, Thusanth; He, Guoan; Radzioch, Danuta; Ding, Aihao

    2010-01-01

    Secretory leukocyte protease inhibitor is a serine protease inhibitor produced by various cell types, including neutrophils and activated macrophages, and has anti-inflammatory properties. It has been shown to promote wound healing in the skin and other non-neural tissues, however, its role in central nervous system injury was not known. We now report a beneficial role for secretory leukocyte protease inhibitor after spinal cord injury. After spinal cord contusion injury in mice, secretory leukocyte protease inhibitor is expressed primarily by astrocytes and neutrophils but not macrophages. We show, using transgenic mice over-expressing secretory leukocyte protease inhibitor, that this molecule has an early protective effect after spinal cord contusion injury. Furthermore, wild-type mice treated for the first week after spinal cord contusion injury with recombinant secretory leukocyte protease inhibitor exhibit sustained improvement in locomotor control and reduced secondary tissue damage. Recombinant secretory leukocyte protease inhibitor injected intraperitoneally localizes to the nucleus of circulating leukocytes, is detected in the injured spinal cord, reduces activation of nuclear factor-κB and expression of tumour necrosis factor-α. Administration of recombinant secretory leukocyte protease inhibitor might therefore be useful for the treatment of acute spinal cord injury. PMID:20047904

  8. Leukocyte Cell Surface Proteinases: Regulation of Expression, Functions, and Mechanisms of Surface Localization

    PubMed Central

    Owen, Caroline A.

    2008-01-01

    A number of proteinases are expressed on the surface of leukocytes including members of the serine, metallo-, and cysteine proteinase superfamilies. Some proteinases are anchored to the plasma membrane of leukocytes by a transmembrane domain or a glycosyl phosphatidyl inositol (GPI) anchor. Other proteinases bind with high affinity to classical receptors, or with lower affinity to integrins, proteoglycans, or other leukocyte surface molecules. Leukocyte surface levels of proteinases are regulated by: 1) cytokines, chemokines, bacterial products, and growth factors which stimulate synthesis and/or release of proteinase by cells; 2) the availability of surface binding sites for proteinases; and/or 3) internalization or shedding of surface-bound proteinases. The binding of proteinases to leukocyte surfaces serves many functions including: 1) concentrating the activity of proteinases to the immediate pericellular environment; 2) facilitating pro-enzyme activation; 3) increasing proteinase stability and retention in the extracellular space; 4) regulating leukocyte function by proteinases signaling through cell surface binding sites or other surface proteins; and 5) protecting proteinases from inhibition by extracellular proteinase inhibitors. There is strong evidence that membrane-associated proteinases on leukocytes play critical roles in wound healing, inflammation, extracellular matrix remodeling, fibrinolysis, and coagulation. This review will outline the biology of membrane-associated proteinases expressed by leukocytes and their roles in physiologic and pathologic processes. PMID:18329945

  9. A simple rapid method for the removal of leukocytes from human blood.

    PubMed

    Palmer, E; Waldman, F; Dewitt, W

    1974-01-01

    Filtration of human blood cells through lamb's wool columns removed more than 96% of all leukocytes in a series of experiments, while the retention of erythrocytes by the column averaged 6.4%. This method should prove extremely useful for obtaining pure erythrocyte preparations for use in biochemical and physiological studies, and for removing leukocytes from blood prior to transfusion. PMID:4473869

  10. Seasonal variation of peripheral blood leukocyte telomere length in Costa Rica: a population based observational study

    PubMed Central

    Rehkopf, David H; Dow, William H; Rosero-Bixby, Luis; Lin, Jue; Epel, Elissa S; Blackburn, Elizabeth H

    2014-01-01

    Objectives Peripheral blood leukocyte telomere length is increasingly being used as a biomarker of aging, but its natural variation in human populations is not well understood. Several other biomarkers show seasonal variation, as do several determinants of leukocyte telomere length. We examined whether there was monthly variation in leukocyte telomere length in Costa Rica, a country with strong seasonal differences in precipitation and infection. Methods We examined a longitudinal population based cohort of 581 Costa Rican adults age 60 and above, from which blood samples were drawn between October 2006 and July 2008. Leukocyte telomere length was assayed from these samples using the quantitative PCR method. Multivariate regression models were used to examine correlations between month of blood draw and leukocyte telomere length. Results Telomere length from peripheral blood leukocytes varied by as much as 200 base pairs depending on month of blood draw, and this difference is not likely to be due to random variation. A moderate proportion of this association is statistically accounted for by month and region specific average rainfall. We found shorter telomere length associated with greater rainfall. Conclusions There are two possible explanations of our findings. First, there could be relatively rapid month-to-month changes in leukocyte telomere length. This conclusion would have implications for understanding the natural population dynamics of telomere length. Second, there could be seasonal differences in constituent cell populations. This conclusion would suggest that future studies of leukocyte telomere length use methods to account for the potential impact of constituent cell type. PMID:24615938

  11. Imaging of vascular development in early mouse decidua and its association with leukocytes and trophoblasts.

    PubMed

    Croy, B Anne; Chen, Zhilin; Hofmann, Alexander P; Lord, Edith M; Sedlacek, Abigail L; Gerber, Scott A

    2012-11-01

    In species with endometrial decidualization and hemochorial placentation (humans, mice, and others), leukocytes localize to early implant sites and contribute to decidual angiogenesis, spiral arterial remodeling, and trophoblast invasion. Relationships between leukocytes, trophoblasts, and the decidual vasculature are not fully defined. Early C57BL/6J implant sites were analyzed by flow cytometry to define leukocyte subsets and by whole-mount immunohistochemistry to visualize relationships between leukocytes, decidual vessels, and trophoblasts. Ptprc(+) (CD45(+)) cells increased in decidua between Gestational Day (GD) 5.5 and GD 9.5. Uterine natural killer (uNK) cells that showed dynamic expression of Cd (CD) 69, an activating receptor, and Klrg1 (KLRG1), an inhibitory receptor, localized mesometrially and were the dominant CD45(+) cells between GD 5.5 and GD 7.5. At GD 8.5, immature monocytes that occurred throughout decidua exceeded uNK cells numerically and many leukocytes acquired irregular shapes, and leukocyte-leukocyte conjugates became frequent. Vessels were morphologically heterogeneous and regionally unique. Migrating trophoblasts were first observed at GD 6.5 and, at GD 9.5, breached endothelium, entered vascular lumens, and appeared to occlude some vessels, as described for human spiral arteries. No leukocyte-trophoblast conjugates were detected. Whole-mount staining gave unparalleled decidual vascular detail and cell-specific positional information. Its application across murine models of pregnancy disturbances should significantly advance our understanding of the maternal-fetal interface. PMID:22954796

  12. Leukocyte accumulation promoting fibrin deposition is mediated in vivo by P-selectin on adherent platelets

    NASA Astrophysics Data System (ADS)

    Palabrica, Theresa; Lobb, Roy; Furie, Barbara C.; Aronovitz, Mark; Benjamin, Christopher; Hsu, Yen-Ming; Sajer, Susan A.; Furie, Bruce

    1992-10-01

    THE glycoprotein P-selectin is a cell adhesion molecule of stimulated platelets and endothelial cells, which mediates the interaction of these cells with neutrophils and monocytes1,2. It is a membrane component of cell storage granules3-6, and is a member of the selectin family which includes E-selectin and L-selectin7,8. P-selectin recognizes both lineage-specific carbohydrate ligands on monocytes and neutrophils, including the Lewis x antigen, sialic acid, and a protein component9-12. In inflammation and thrombosis, P-selectin may mediate the interaction of leukocytes with platelets bound in the region of tissue injury and with stimulated endothelium1,2. To evaluate the role of P-selectin in platelet-leukocyte adhesion in vivo, the accumulation of leukocytes within an experimental thrombus was explored in an arteriovenous shunt model in baboons13. A Dacron graft implanted within an arteriovenous shunt is thrombogenic, accumulating platelets and fibrin within its lumen. These bound platelets express P-selectin14. Here we show that antibody inhibition of leukocyte binding to P-selectin expressed on platelets immobilized on the graft blocks leukocyte accumulation and inhibits the deposition of fibrin within the thrombus. These results indicate that P-selectin is an important adhesion molecule on platelets, mediating platelet-leukocyte binding in vivo, that the presence of leukocytes in thrombi is mediated by P-selectin, and that these leukocytes promote fibrin deposition.

  13. Receptor cleavage and P-selectin-dependent reduction of leukocyte adhesion in the spontaneously hypertensive rat.

    PubMed

    Chen, Angela Y; Ha, Jessica N; Delano, Frank A; Schmid-Schönbein, Geert W

    2012-07-01

    The SHR, a genetic model for hypertension and the metabolic syndrome, has attenuated leukocyte adhesion to the postcapillary endothelium by an unknown mechanism. Based on recent evidence of elevated levels of MMPs in plasma and on microvascular endothelium of the SHR with cleavage of several receptor types, we hypothesize that the reduced leukocyte-endothelial interaction is a result of enhanced proteolytic cleavage of P-selectin on the postcapillary endothelium and PSGL-1 on leukocytes. The attenuated rolling interactions of SHR leukocytes with the endothelium were restored by chronic treatment with a broad-spectrum MMP inhibitor (CGS) for 24 weeks. The SHR MMP levels, in plasma and mesentery, as well as the systolic blood pressure, decreased significantly with treatment. In the SHR mesentery, labeling of P-selectin in the postcapillary venules by immunohistochemistry demonstrated, on average, a 31% lower extracellular P-selectin density compared with the normotensive WKY. A significantly lower extracellular PSGL-1 density on the membranes of SHR neutrophils compared with the WKY also supported our hypothesis. In vivo stimulation of the mesenteric postcapillary venules with histamine demonstrated that the SHR had an attenuated response, as measured by leukocyte rolling velocity on the endothelium. The reduced P-selectin and PSGL-1 density, on SHR postcapillary endothelium and on SHR leukocytes, respectively, was restored significantly by chronic MMP inhibition. The impaired ability of SHR leukocytes to reduce rolling velocity upon inflammatory stimulation led to fewer firmly adhered leukocytes to the endothelium as a contributor to immune suppression. PMID:22566571

  14. HARVESTING OF LEUKOCYTES FROM INTESTINAL LUMEN IN MURINE GIARDIASIS AND PRELIMINARY CHARACTERIZATION OF THESE CELLS

    EPA Science Inventory

    The aims of the study were to develop a method for harvesting leukocytes from the mouse small intestinal lumen and to identify leukocytes which enter the intestinal lumen of mice infected with Giardia muris. Giardia-infected and uninfected BALB/c mice were anesthetized, and the s...

  15. Fragmentation of gelatin-bound fibronectin (Fn) by inflammatory polymorphonuclear leukocytes (PMNL): A role for leukocyte elastase

    SciTech Connect

    Daudi, I.; Gudewicz, P.W.; Saba, T.M.; Cho, E.; Lewis, M. )

    1990-02-26

    Fragmentation of lung matrix Fn by proteases released from activated leukocytes sequestered in the lung has been implicated in lung vascular injury. The authors determined if Fn bound to a denatured collagen (gelatin) surface was susceptible to degradation by inflammatory PMNLs. Tissue culture wells coated with 1.5% denatured collagen (2 ml/well) prior to the addition of rat peritonal exudate cells, harvested 16 hours after i.p. sterile casein. Inflammatory PMNLs (1 {times} 10{sup 6}) stimulated with zymosan (1 mg) released 3 times more {sup 125}I-Fn into the culture media (DMEM) during a 4 hour incubation as compared to unstimulated PMNLs (2885{plus minus}95 cpm vs 1027{plus minus}82 cpm/100 ul). {sup 125}I-Fn released by stimulated PMNLs was markedly blocked by addition of a leukocyte elastase inhibitor (AAPVCK), moderately blocked by a trypsin inhibitor (TLCK), and not blocked by a thrombin inhibitor (Hirudin). Western blot analysis demonstrated fragmentation of released Fn. Thus, Fn complexed with denatured collagen is susceptible to proteolysis by stimulated inflammatory PMNLs. This may contribute to lung vascular injury with sepsis and intravascular coagulation which elicit sequestration of activated PMNLs in the lung.

  16. Expression of beta 2 integrins on blood leukocytes of cows with or without bovine leukocyte adhesion deficiency.

    PubMed

    Cox, E; Mast, J; MacHugh, N; Schwenger, B; Goddeeris, B M

    1997-09-19

    Peripheral blood leukocytes of 11 normal cows, 7 cows heterozygous and 2 heifers homozygous for bovine leukocyte adhesion deficiency (BLAD) were analysed by flow cytometry for the intensity of their beta 2 integrin expression (LFA-1(CD11a/CD18), CR3 (CD11b/CD18) and CR4 (CD11c/CD18)). BLAD-homozygotes revealed no or a very weak expression of the beta 2 integrins and had a 10-fold and 4- to 5-fold increase in absolute number of neutrophils and monocytes, respectively, whereas the absolute number of lymphocytes remained normal. The mean fluorescence intensity (MFI) of the beta 2 integrins (CD18) in heterozygous animals was 56 to 90% of this in the normal cows (MFI between 14 and 512). The difference in the expression level was most pronounced for LFA-1 on the small cluster of lymphocytes with the highest MFI for LFA-1. Repeated analysis and phorbol myristate acetate stimulation revealed that the LFA-1 expression on this high-expressing cell population of the peripheral blood allowed a ready identification of BLAD-heterozygotes by flow cytometry. PMID:9436269

  17. Finite resolution multitarget tracking

    NASA Astrophysics Data System (ADS)

    Mušicki, Darko; Morelande, Mark R.

    2005-09-01

    Target tracking algorithms have to operate in an environment of uncertain measurement origin, due to the presence of randomly detected target measurements as well as clutter measurements from unwanted random scatterers. A majority of Bayesian multi-target tracking algorithms suffer from computational complexity which is exponential in the number of tracks and the number of shared measurements. The Linear Multi-target (LM) tracking procedure is a Bayesian multi-target tracking approximation with complexity which is linear in the number of tracks and the number of shared measurements. It also has a much simpler structure than the "optimal" Bayesian multi-target tracking, with apparently negligible decrease in performance. A vast majority of target tracking algorithms have been developed with the assumption of infinite sensor resolution, where a measurement can have only one source. This assumption is not valid for real sensors, such as radars. This paper presents a multi-target tracking algorithm which removes this restriction. The procedure utilizes a simple structure of LM tracking procedure to obtain a LM Finite Resolution (LMfr) tracking procedure which is much simpler than the previously published efforts. Instead of calculating the probability of measurement merging for each combination of potentially merging targets, we evaluate only one merging hypotheses for each measurement and each track. A simulation study is presented which compares LMfr-IPDA with LM-IPDA and IPDA target tracking in a cluttered environment utilizing a finite resolution sensor with five crossing targets. The study concentrates on the false track discrimination performance and the track retention capabilities.

  18. Tracking results using a standard cell lattice

    SciTech Connect

    Gelfand, N.M.

    1987-10-01

    This is a summary of results obtained by tracking a single particle through a lattice composed of a r.f. cavity and standard FODO cells. The lattice also includes two families of sextupoles for controlling the chromaticity. The parameters of the cells, i.e. their length and phase advance, closely resemble those of the Fermilab Main Ring or the Tevatron. We therefore have a model lattice which is similar to that of those accelerators but without the straight sections present in the actual machines. It is hoped that the simplified model used will exhibit the salient features of the actual accelerator but will be simpler to understand. 8 figs., 1 tab.

  19. Beam Dynamics Design and Simulation in Ion Linear Accelerators (

    2006-08-01

    Orginally, the ray tracing code TRACK has been developed to fulfill the many special requirements for the Rare Isotope Accelerator Facility known as RIA. Since no available beam-dynamics code met all the necessary requirements, modifications to the code TRACK were introduced to allow end-to-end (from the ion souce to the production target) simulations of the RIA machine, TRACK is a general beam-dynamics code and can be applied for the design, commissioning and operation of modernmore » ion linear accelerators and beam transport systems.« less

  20. Beam Dynamics Design and Simulation in Ion Linear Accelerators (

    SciTech Connect

    Ostroumov, Peter N.; Asseev, Vladislav N.; Mustapha, and Brahim

    2006-08-01

    Orginally, the ray tracing code TRACK has been developed to fulfill the many special requirements for the Rare Isotope Accelerator Facility known as RIA. Since no available beam-dynamics code met all the necessary requirements, modifications to the code TRACK were introduced to allow end-to-end (from the ion souce to the production target) simulations of the RIA machine, TRACK is a general beam-dynamics code and can be applied for the design, commissioning and operation of modern ion linear accelerators and beam transport systems.

  1. Alpha 1-proteinase inhibitor is more sensitive to inactivation by cigarette smoke than is leukocyte elastase

    SciTech Connect

    Janoff, A.; Dearing, R.

    1982-10-01

    Aqueous solutions of gas phase cigarette smoke were incubated with pure human leukocyte elastase or with crude human leukocyte granule extract, and the effects on enzyme activity were determined using a synthetic amide substrate. Simultaneously, the same smoke solutions were incubated with 10% human serum under identical conditions, and the effects on serum inhibition of purified or crude leukocyte elastase were similarly measured. In addition, aqueous solutions of unfractionated cigarette smoke were incubated with leukocyte elastase or serum, and the abilities of the smoke-treated enzyme to digest elastin and of the smoke-treated serum to inhibit elastin digestion were determined. Both experimental protocols showed that serum elastase-inhibiting capacity (primarily caused by alpha 1-proteinase inhibitor) is more susceptible to inactivation by aqueous solutions of cigarette smoke than is leukocyte elastase, suggesting that elastase inhibition (rather than elastase activity) may be predominantly suppressed by cigarette smoke inhalation in vivo.

  2. N-Formylmethionyl Peptide Receptors on Equine Leukocytes Initiate Secretion but not Chemotaxis

    NASA Astrophysics Data System (ADS)

    Snyderman, Ralph; Pike, Marilyn C.

    1980-07-01

    The chemotaxis of leukocytes appears to be initiated by the binding of chemotactic factors to the surface of these cells. N-Formylated peptides induce chemotaxis and lysosomal enzyme secretion of leukocytes; because these peptides are available in a purified radiolabeled form, they have been useful in the characterization of receptors for chemotactic factors. Equine polymorphonuclear leukocytes secrete lysosomal enzymes but do not exhibit chemotaxis in response to the N-formylated peptides, even though they have a high-affinity cell surface receptor for these agents. The specificity of the equine receptor resembles the specificity of the receptor on chemotactically responsive leukocytes from other species. Equine polymorphonuclear leukocytes may thus be an excellent model for the study of the events that lead to a biological response following receptor occupancy.

  3. Tc-99m labeled leukocytes: preparation and use in identification of abscess and tissue rejection

    SciTech Connect

    Farid, N.A.; White, S.M.; Heck, L.L.; Van Hove, E.D.

    1983-09-01

    A simple and reproducible method for the preparation and labeling of leukocytes with Tc-99m has been developed. Leukocytes were separated from blood, incubated with stannous pyrophosphate, and then with 20-30 mCi (740-1110 MBq) of /sup 99m/TcO-4. In leukocytes separated from human blood, the labeling efficiency was 81% +/- 6% (n . 4). Experiments on dogs with abscesses showed accumulation of the Tc-99m-labeled leukocytes in the infected sites, indicating the viability of the labeled leukocytes. Additional studies showed that rat lymphocytes that were labeled with Tc-99m, using the same technique, localized in heart transplant tissue that was being rejected.

  4. Tc-99m labeled leukocytes: preparation and use in identification of abscess and tissue rejection

    SciTech Connect

    Farid, N.A.; White, S.M.; Heck, L.L.; Van Hove, E.D.

    1983-09-01

    A simple and reproducible method for the preparation and labeling of leukocytes with Tc-99m, has been developed. Leukocytes were separated from blood, incubated with stannous pyrophosphate, and then with 20-30 mCi (740-1110 M Bq) of /sup 99m/TcO/sub 4//sup -/. In leukocytes separated from human blood, the labeling efficiency was 81% +/- 6% (n=4). Experiments on dogs with abscesses showed accumulation of the Tc-99m-labeled leukocytes in the infected sites, indicating the viability of the labeled leukocytes. Additional studies showed that rat lymphocytes that were labeled with Tc-99m, using the same technique, localized in heart transplant tissue that was being rejected.

  5. Effect of plastic catheters on the phagocytic activity of human polymorphonuclear leukocytes.

    PubMed

    López-López, G; Pascual, A; Perea, E J

    1990-05-01

    The effect of five kinds of plastic catheters (polyvinyl chloride, Teflon, polyurethane, Vialon and siliconized latex) on the phagocytic and bactericidal function of human polymorphonuclear leukocytes was evaluated. In the presence of the polyvinyl chloride, Teflon and siliconized latex catheters, superoxide radical production by polymorphonuclear leukocytes was significantly inhibited. The effect of the siliconized latex catheter was presumably mediated by products eluted from the catheter into the medium, since the incubation of polymorphonuclear leukocytes in eluates obtained from the incubation of this catheter in buffer induced a similar inhibitory effect. This phenomenon was not observed with polyurethane or Vialon catheters. Neither the catheters evaluated nor their eluates affected the uptake of opsonized Staphylococcus aureus by human polymorphonuclear leukocytes. It is concluded that the polyvinyl chloride, Teflon and siliconized latex catheters used in this study could impair the respiratory burst of human polymorphonuclear leukocytes. PMID:2164932

  6. Object tracking with stereo vision

    NASA Technical Reports Server (NTRS)

    Huber, Eric

    1994-01-01

    A real-time active stereo vision system incorporating gaze control and task directed vision is described. Emphasis is placed on object tracking and object size and shape determination. Techniques include motion-centroid tracking, depth tracking, and contour tracking.

  7. Vehicle track loading simulation

    NASA Astrophysics Data System (ADS)

    Chalupa, Milan; Severa, Libor; Vlach, Radek

    2011-12-01

    The paper describes possible design of the vehicle track computational model and basic testing procedure of the track dynamic loading simulation. The proposed approach leads to an improvement of track vehicle course stability. The computational model is built for MSC. ADAMS, AVT computational simulating system. Model, which is intended for MSC computational system, is built from two basic parts. The first one is represented by geometrical part, while the second one by contact computational part of the model. The aim of the simulating calculation consist in determination of change influence of specific vehicle track constructive parameters on changes of examined qualities of the vehicle track link and changes of track vehicle course stability. The work quantifies the influence of changes of track preloading values on the demanded torque changes of driving sprocket. Further research possibilities and potential are also presented.

  8. Influence of human leukocyte antigen matching on liver allograft survival and rejection: "the dualistic effect".

    PubMed

    Donaldson, P; Underhill, J; Doherty, D; Hayllar, K; Calne, R; Tan, K C; O'Grady, J; Wight, D; Portmann, B; Williams, R

    1993-06-01

    To date only one published large series of human leukocyte antigen matching and liver allograft survival exists, and considerable confusion has arisen about the advantage or disadvantage of human leukocyte antigen matching. In the present study we have reinvestigated the relationship between human leukocyte antigen mismatch and graft survival in 466 first liver allografts, seeking to clarify the relationship between human leukocyte antigen and both acute rejection and the vanishing bile duct syndrome. In view of current criticism regarding the accuracy of serological tissue typing for human leukocyte antigen-DR, we have used both classic serology and restriction fragment length polymorphism analysis to ensure the accurate assignment of recipient DR types. In addition, we have used polymerase chain reaction amplification and allele-specific and sequence-specific oligonucleotide probes to retest the hypothesis that human leukocyte antigen class II matching may increase susceptibility to the vanishing bile duct syndrome. One-year graft survival was significantly lower in patients with zero or two human leukocyte antigen-A mismatches (52% and 63%, respectively) than in those with one human leukocyte antigen--A mismatch (69%) (p = 0.016 and p = 0.018). A similar effect of B mismatching was observed, with a 1-yr graft survival of 73% for those with one compared with 60% for those with two human leukocyte antigen-B mismatches. In contrast no correlation was found between DR mismatch and graft survival. Human leukocyte antigen class I matching appears to influence graft survival largely through the occurrence of acute rejection and the development of the vanishing bile duct syndrome.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8514248

  9. Sim Track User's Manual (v 1.0)

    SciTech Connect

    Luo, Y.

    2010-01-27

    SimTrack is a simple c++ library designed for the numeric particle tracking in the high energy accelerators. It adopts the 4th order symplectic integrator for the optical transport in the magnetic elements. The 4-D and 6-D weak-strong beam-beam treatments are integrated in it for the beam-beam studies. SimTrack is written with c++ class and standard template library. It provides versatile functions to manage elements and lines. It supports a large range of types of elements. New type of element can be easily created in the library. SimTrack calculates Twiss, coupling and fits tunes, chromaticities and corrects closed orbits. AC dipole and AC multipole are available in this library. SimTrack allows change of element parameters during tracking.

  10. Acceleration modules in linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Heng; Deng, Jian-Jun

    2014-05-01

    The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.

  11. Human Leukocyte Antigen Diversity: A Southern African Perspective

    PubMed Central

    Tshabalala, Mqondisi; Mellet, Juanita; Pepper, Michael S.

    2015-01-01

    Despite the increasingly well-documented evidence of high genetic, ethnic, and linguistic diversity amongst African populations, there is limited data on human leukocyte antigen (HLA) diversity in these populations. HLA is part of the host defense mechanism mediated through antigen presentation to effector cells of the immune system. With the high disease burden in southern Africa, HLA diversity data is increasingly important in the design of population-specific vaccines and the improvement of transplantation therapeutic interventions. This review highlights the paucity of HLA diversity data amongst southern African populations and defines a need for information of this kind. This information will support disease association studies, provide guidance in vaccine design, and improve transplantation outcomes. PMID:26347896

  12. Porcine leukocyte 5- and 12-lipoxygenases are iron enzymes.

    PubMed

    Kroneck, P M; Cucurou, C; Ullrich, V; Ueda, N; Suzuki, H; Yoshimoto, T; Matsuda, S; Yamamoto, S

    1991-08-01

    5- and 12-lipoxygenases isolated from porcine leukocytes were investigated by electron paramagnetic resonance at X-band and atomic absorption spectroscopy. For comparison potato 5-lipoxygenase was studied under identical experimental conditions. All three lipoxygenases contained between 0.7 and 0.9 Fe atoms/enzyme molecule. As isolated, both mammalian enzymes exhibited a characteristic EPR signal at low magnetic field with a maximum at g = 5.20 indicative of a high-spin ferric iron center. The signal was not affected by the oxidants 12-hydroperoxyeicosatetraenoic acid or arachidonic acid, nor was it affected by the reductant nordihydroguaiaretic acid. In the case of the potato enzyme an intense EPR signal with resonances at g = 7.50, 6.39 and 5.84 was only observed after addition of an oxidant, such as 9-hydroperoxyoctadecadienoic acid. PMID:1652456

  13. A1/Bfl-1 in leukocyte development and cell death

    PubMed Central

    Ottina, Eleonora; Tischner, Denise; Herold, Marco J.; Villunger, Andreas

    2012-01-01

    The function of the anti-apoptotic Bcl-2 family member Bcl2a1/Bfl-1/A1 is poorly understood due to the lack of appropriate loss-of-function mouse models and redundant effects with other Bcl-2 pro-survival proteins upon overexpression. Expression analysis of A1 suggests predominant roles in leukocyte development, their survival upon viral or bacterial infection, as well as during allergic reactions. In addition, A1 has been implicated in autoimmunity and the pathology and therapy resistance of hematological as well as solid tumors that may aberrantly express this protein. In this review, we aim to summarize current knowledge on A1 biology, focusing on its role in the immune system and compare it to that of other pro-survival Bcl-2 proteins. PMID:22342458

  14. Chronic stress, leukocyte subpopulations, and humoral response to latent viruses

    SciTech Connect

    McKinnon, W.; Weisse, C.S.; Reynolds, C.P.; Bowles, C.A.; Baum, A. )

    1989-01-01

    Psychological stress has been shown to affect immune system status and function, but most studies of this relationship have focused on acute stress and/or laboratory situations. The present study compared total numbers of leukocytes and lymphocyte subpopulations (determined by flow cytometry) and antibody titers to latent and nonlatent viruses among a group of chronically stressed individuals living near the damaged Three Mile Island (TMI) nuclear power plant with those of a demographically comparable control group. Urinary catecholamine and cortisol levels were also examined. Residents of the TMI area exhibited greater numbers of neutrophils, which were positively correlated with epinephrine levels. The TMI group also exhibited fewer B lymphocytes, T-suppressor/cytotoxic lymphocytes, and natural killer cells. Antibody titers to herpes simplex were significantly different across groups as well, whereas titers to nonlatent rubella virus as well as IgG and IgM levels were comparable.

  15. Chronic stress, leukocyte subpopulations, and humoral response to latent viruses.

    PubMed

    McKinnon, W; Weisse, C S; Reynolds, C P; Bowles, C A; Baum, A

    1989-01-01

    Psychological stress has been shown to affect immune system status and function, but most studies of this relationship have focused on acute stress and/or laboratory situations. The present study compared total numbers of leukocytes and lymphocyte subpopulations (determined by flow cytometry) and antibody titers to latent and nonlatent viruses among a group of chronically stressed individuals living near the damaged Three Mile Island (TMI) nuclear power plant with those of a demographically comparable control group. Urinary catecholamine and cortisol levels were also examined. Residents of the TMI area exhibited greater numbers of neutrophils, which were positively correlated with epinephrine levels. The TMI group also exhibited fewer B lymphocytes, T-suppressor/cytotoxic lymphocytes, and natural killer cells. Antibody titers to herpes simplex were significantly different across groups as well, whereas titers to nonlatent rubella virus as well as IgG and IgM levels were comparable. PMID:2555149

  16. Human Leukocyte Antigen Diversity: A Southern African Perspective.

    PubMed

    Tshabalala, Mqondisi; Mellet, Juanita; Pepper, Michael S

    2015-01-01

    Despite the increasingly well-documented evidence of high genetic, ethnic, and linguistic diversity amongst African populations, there is limited data on human leukocyte antigen (HLA) diversity in these populations. HLA is part of the host defense mechanism mediated through antigen presentation to effector cells of the immune system. With the high disease burden in southern Africa, HLA diversity data is increasingly important in the design of population-specific vaccines and the improvement of transplantation therapeutic interventions. This review highlights the paucity of HLA diversity data amongst southern African populations and defines a need for information of this kind. This information will support disease association studies, provide guidance in vaccine design, and improve transplantation outcomes. PMID:26347896

  17. Evaluation of leptin receptor expression on buffalo leukocytes.

    PubMed

    De Matteis, Giovanna; Grandoni, Francesco; Scatà, Maria Carmela; Catizone, Angela; Reale, Anna; Crisà, Alessandra; Moioli, Bianca

    2016-09-01

    Experimental evidences support a direct role for leptin in immunity. Besides controlling food intake and energy expenditure, leptin was reported to be involved in the regulation of the immune system in ruminants. The aim of this work was to highlight the expression of leptin receptor (LEPR) on Bubalus bubalis immune cells using a multi-approach assessment: flow cytometry, confocal microscopy and gene expression analysis. Flow cytometric analysis of LEPR expression showed that peripheral blood monocytes were the predominant cells expressing LEPR. This result was corroborated by confocal microscopy and RT-PCR analysis. Moreover, among lymphocytes, LEPR was mainly expressed by B lymphocytes and Natural Killer cells. Evidence of LEPR expression on buffalo blood leukocytes showed to be a good indicator of the responsivity of these cells to leptin, so confirming the involvement of leptin in buffalo immune response. PMID:27436440

  18. Flow cytofluorometric monitoring of leukocyte apoptosis in experimental cholera

    NASA Astrophysics Data System (ADS)

    Lotsmanova, Ekaterina Y.; Kravtsov, Alexander L.; Livanova, Ludmila F.; Kobkova, Irina M.; Kuznetsov, Oleg S.; Shchukovskaya, Tatyana N.; Smirnova, Nina I.; Kutyrev, Vladimir V.

    2003-10-01

    Flow cytofluorometric DNA analysis was applied to determine of the relative contents of proliferative (more then 2C DNA per cell) and apoptotic (less then 2C DNA per cell) leukocytes in blood of adult rabbits, challenged with 10,000 times the 50 % effective dose of Vibrio cholerae virulent strain by the RITARD technique. It has been shown that irreversible increase the percentage of cells carrying DNA in the degradation stage brings to disbalance between the genetically controlled cell proliferation and apoptosis that leads to animal death from the cholera infection. Such fatal changes were not observed in challenging of immunized animals that were not died. Thus received data show that the flow cytofluorometric measurements may be used for detection of transgressions in homeostasis during acute infection diseases, for outlet prognosis of the cholera infection.

  19. Cardiac and vascular imaging with labeled platelets and leukocytes

    SciTech Connect

    Dewanjee, M.K.

    1984-07-01

    The contribution of platelets in atherosclerosis and thrombosis in animal models and in clinical studies has been quantified with 111In-platelet scintigraphy. New in vitro quantitative techniques have been developed using 111In-labeled platelets to determine the number of adherent platelets on deendothelialized surfaces of damaged vessel walls and synthetic vascular grafts. In vivo imaging techniques are semi-quantitative in nature; in these studies 111In radioactivity on thrombotic vessels or graft surfaces of iliac, femoral, or popliteal arteries is compared with contralateral vessels. Background 111In radioactivity in the circulating blood pool of venous and capillary networks and radioactivity in marrow decreases the sensitivity of these techniques. Subtraction of blood pool radioactivity with 99mTc-labeled autologous red cells and calculation of 111In radioactivity associated with platelet thrombus on vessel walls also have been performed for coronary, carotid, and femoral arteries. Although platelet concentrates are used frequently after open heart surgery (one to six per patient), consumption of platelets in the artificial lung or oxygenator, lysis of platelets during pumping, and suction of blood only recently have been quantified with the use of 111In-labeled platelets. These studies also demonstrated far less trauma to platelets with the use of a membrane rather than a bubble oxygenator. Further reduction in platelet consumption and trauma was observed with the use of prostacyclin, a short-acting drug with significant beneficial effect on platelet thrombus reduction and disaggregation of aggregated platelets. The role of polymorphonuclear leukocytes in inflammation, infection and myocardial infarction, and in vivo evaluation with 111In-leukocyte scintigraphy in animals and humans has been described.

  20. A continuum model of protrusion of pseudopod in leukocytes.

    PubMed Central

    Zhu, C; Skalak, R

    1988-01-01

    The morphology of human leukocytes, the biochemistry of actin polymerization, and the theory of continuum mechanics are used to model the pseudopod protrusion process of leukocytes. In the proposed model, the pseudopod is considered as a porous solid of F-actin network, the pores of which are full of aqueous solution. G-actin is considered as a "solute" transported by convection and diffusion in the fluid phase. The pseudopod grows as actin filaments elongate at their barbed ends at the tip of the pseudopod. The driving force of extension is hypothesized as being provided by the actin polymerization. It is assumed that elongation of actin filaments, powered by chemical energy liberated from the polymerization reaction, does mechanical work against opposing pressure on the membrane. This also gives rise to a pressure drop in the fluid phase at the tip of the pseudopod, which is formulated by an equation relating the work done by actin polymerization to the local state of pressure. The pressure gradient along the pseudopod drives the fluid filtration through the porous pseudopod according to Darcy's Law, which in turn brings more actin monomers to the growing tip. The main cell body serves as a reservoir of G-actin. A modified first-order equation is used to describe the kinetics of polymerization. The rate of pseudopod growth is modulated by regulatory proteins. A one-dimensional moving boundary problem based on the proposed mechanism has been constructed and approximate solutions have been obtained. Comparison of the solutions with experimental data shows that the model is compatible with available observations. The model is also applicable to growth of other cellular systems such as elongation of acrosomal process in sperm cells. Images FIGURE 1 FIGURE 4 PMID:3233268

  1. Tracking dynamic team activity

    SciTech Connect

    Tambe, M.

    1996-12-31

    AI researchers are striving to build complex multi-agent worlds with intended applications ranging from the RoboCup robotic soccer tournaments, to interactive virtual theatre, to large-scale real-world battlefield simulations. Agent tracking - monitoring other agent`s actions and inferring their higher-level goals and intentions - is a central requirement in such worlds. While previous work has mostly focused on tracking individual agents, this paper goes beyond by focusing on agent teams. Team tracking poses the challenge of tracking a team`s joint goals and plans. Dynamic, real-time environments add to the challenge, as ambiguities have to be resolved in real-time. The central hypothesis underlying the present work is that an explicit team-oriented perspective enables effective team tracking. This hypothesis is instantiated using the model tracing technology employed in tracking individual agents. Thus, to track team activities, team models are put to service. Team models are a concrete application of the joint intentions framework and enable an agent to track team activities, regardless of the agent`s being a collaborative participant or a non-participant in the team. To facilitate real-time ambiguity resolution with team models: (i) aspects of tracking are cast as constraint satisfaction problems to exploit constraint propagation techniques; and (ii) a cost minimality criterion is applied to constrain tracking search. Empirical results from two separate tasks in real-world, dynamic environments one collaborative and one competitive - are provided.

  2. Progress on plasma accelerators

    SciTech Connect

    Chen, P.

    1986-05-01

    Several plasma accelerator concepts are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wake Field Accelerator (PWFA). Various accelerator physics issues regarding these schemes are discussed, and numerical examples on laboratory scale experiments are given. The efficiency of plasma accelerators is then revealed with suggestions on improvements. Sources that cause emittance growth are discussed briefly.

  3. Ground maneuvering target tracking based on the strong tracking and the cubature Kalman filter algorithms

    NASA Astrophysics Data System (ADS)

    Gao, Min; Zhang, Heng; Zhou, Yulong; Zhang, Baoquan

    2016-03-01

    In an effort to improve the tracking accuracy of the ground maneuvering target in infrared images, a method is proposed based on the strong tracking filter (STF) and the cubature Kalman filter (CKF) algorithms. In this method, the fading factor is introduced from the STF algorithm and is calculated by transforming the nonlinear measurement variance matrix to be linear approximately, and then the fading factor is used to correct the prediction error covariance matrix (PECM) of CKF, so that the gain matrix can be adjusted at real time and hence the tracking ability of the maneuvering target could be improved. After the digital simulation experiment, it is shown that, comparing with CKF and the unscented Kalman filter algorithms, the average tracking accuracy of the location is increased by more than 20% with the target velocity under 20 m/s and acceleration under 5 m/s2, and it can even be increased by 50% when the target step maneuver occurs. With the tracking experiment on the real infrared tank images, it can be concluded that the target could be tracked stably by the proposed method, and the maximum tracking error is not more than 8 pixels even though the 180 deg turning takes place.

  4. Real-time tracking of deformable objects based on combined matching-and-tracking

    NASA Astrophysics Data System (ADS)

    Yan, Junhua; Wang, Zhigang; Wang, Shunfei

    2016-03-01

    Visual tracking is very challenging due to the existence of several sources of variations, such as partial occlusion, deformation, scale variation, rotation, and background clutter. A model-free tracking method based on fusing accelerated features using fast explicit diffusion in nonlinear scale spaces (AKAZE) and KLT features is presented. First, matching-keypoints are generated by finding corresponding keypoints from the consecutive frames and the object template, then tracking-keypoints are generated using the forward-backward flow tracking method, and at last, credible keypoints are obtained by AKAZE-KLT tracking (AKT) algorithm. To avoid the instability of a statistical method, the median method is adopted to compute the object's location, scale, and rotation in each frame. The experimental results show that the AKT algorithm has strong robustness and can achieve accurate tracking especially under conditions of partial occlusion, scale variation, rotation, and deformation. The tracking performance shows higher robustness and accuracy in a variety of datasets and the average frame rate reaches 78 fps, showing good performance in real time.

  5. PHYSIOLOGICAL AND LEUKOCYTE SUBSET RESPONSES TO EXERCISE AND COLD EXPOSURE IN COLD-ACCLIMATIZED SKATERS

    PubMed Central

    Suzuki, K.; Peake, J.; Ahn, N.; Ogawa, K.; Hong, Ch.; Kim, S.; Lee, I.; Park, J.

    2014-01-01

    We investigated physiological responses and changes in circulating immune cells following exercise in cold and thermoneutral conditions. Participants were short track skaters (n=9) who were acclimatized to cold conditions, and inline skaters (n=10) who were not acclimatized. All skaters were young, and skating at a recreational level three days per week for at least one year. Using a cross-over design, study variables were measured during 60 min of submaximal cycling (65% V.O2max) in cold (ambient temperature: 5±1°C, relative humidity: 41±9%) and thermoneutral conditions (ambient temperature: 21±1°C, relative humidity: 35±5%). Heart rate, blood lactate and tympanic temperature were measured at rest, during exercise and recovery. Plasma cortisol, calprotectin and circulating blood cell numbers were measured before and after 60 min of cold or thermoneutral conditions, and during recovery from exercise. Heart rate was lower in both groups during exercise in cold versus thermoneutral conditions (P<0.05). The increase in total leukocytes during recovery was primarily due to an increase in neutrophils in both groups. The cold-acclimatized group activated neutrophils after exercise in cold exposure, whereas the non-acclimatized group activated lymphocyte and cortisol after exercise in cold exposure. Lymphocyte subsets significantly changed in both groups over time during recovery as compared to rest. Immediately after exercise in both groups, CD16+ and CD69+ cells were elevated compared to rest or before exercise in both conditions. Acclimatization to exercise in the cold does not appear to influence exercise-induced immune changes in cold conditions, with the possible exception of neutrophils, lymphocytes and cortisol concentration. PMID:24917688

  6. Antirheumatic agents and leukocyte recruitment. New light on the mechanism of action of oxaceprol.

    PubMed

    Parnham, M J

    1999-07-15

    Most anti-inflammatory agents used in the treatment of joint diseases exert inhibitory effects on leukocyte infiltration. Methotrexate, a disease-modifying drug, and corticosteroids also inhibit leukocyte accumulation during inflammation. However, the mechanisms of action of these different compounds on leukocytes vary and in the case of non-steroidal anti-inflammatory drugs (NSAIDs) the mechanism(s) may be indirect. No current drug for inflammatory or degenerative joint disease has been proposed to act specifically by an inhibitory action on neutrophilic leukocytes. Oxaceprol is an amino acid derivative that has been used for several years for the treatment of osteoarthritis and rheumatoid arthritis, ameliorating pain and stiffness and showing good gastrointestinal safety, particularly in comparison with NSAIDs. Recent experimental studies have shown that oxaceprol does not inhibit the synthesis of prostaglandins in vitro, but markedly inhibits neutrophil infiltration into the joints of rats with adjuvant arthritis. These results support earlier screening data showing inhibition by oxaceprol of leukocyte infiltration into sites of acute inflammation. In studies on surgical ischemia reperfusion in hamsters in vivo, oxaceprol was an effective inhibitor of leukocyte adhesion and extravasation. It is proposed that oxaceprol represents a therapeutic agent for degenerative and inflammatory joint diseases, which acts predominantly by inhibiting leukocyte adhesion and migration. PMID:10423160

  7. p,p'-DDE depresses the immune competence of chinook salmon (Oncorhynchus tshawytscha) leukocytes

    USGS Publications Warehouse

    Misumi, Ichiro; Vella, Anthony T.; Leong, Jo-Ann C.; Nakanishi, Teruyuki; Schreck, Carl B.

    2005-01-01

    p,p′-DDE, the main metabolite of DDT, is still detected in aquatic environments throughout the world. Here, the effects and mechanisms by which p,p′-DDE exposure might affect the immune system of chinook salmon (Oncorhynchus tshawytscha) was studied. Isolated salmon splenic and pronephric leukocytes were incubated with different concentrations of p,p′-DDE, and cell viability, induction of apoptosis, and mitogenic responses were measured by flow cytometry and Alamar Blue assay. p,p′-DDE significantly reduced cell viability and proliferation and increased apoptosis. The effect of p,p′-DDE on pronephric leukocytes was more severe than on splenic leukocytes, likely because pronephric leukocytes had a higher proportion of granulocytes, cells that appear more sensitive to p,p′-DDE. The effect of p,p′-DDE on leukocytes appeared to vary between developmental stages or seasonal differences. The mitogenic response of leukocytes of chinook salmon exposed to p,p′-DDE in vivo exhibited a biphasic dose–response relationship. Only leukocytes isolated from salmon treated with 59 ppm p,p′-DDE had a significantly lower percentage of Ig+ blasting cells than controls, although the response was biphasic. These results support the theory that exposure to chemical contaminants could lead to an increase in disease susceptibility and mortality of fish due to immune suppression.

  8. Fish Oil and Adjuvant-Induced Arthritis: Inhibitory Effect on Leukocyte Recruitment.

    PubMed

    Estevão-Silva, Camila Fernanda; Ames, Franciele Queiroz; Silva-Comar, Francielli Maria de Souza; Kummer, Raquel; Tronco, Rafael Prizon; Cuman, Roberto Kenji Nakamura; Bersani-Amado, Ciomar Aparecida

    2016-02-01

    Fish oil, a rich source of n-3 fatty acids, has been studied for its beneficial effects in many diseases. Recent studies have shown the robust anti-inflammatory activity of fish oil (FO), when administered orally to rats, in models of acute inflammation. Herein, we investigated if treatment with fish oil preparation (FOP) could interfere with the recruitment of leukocytes into the joint cavity of arthritic rats. We also evaluated the effect of treatment on rolling behavior and leukocyte adhesion in vivo and on leukocyte chemotaxis in vitro. Treatment with FOP (75, 150, and 300 mg/kg) initiated on the day of induction of arthritis (day 0) and maintained for 21 days reduced the total number of leukocytes recruited into the joint cavity, the number of rolling and adhered leukocytes in arthritic rats, and leukocyte migration in response to stimulation with N-formyl-methionyl-leucyl-phenylalanine (fMLP) and leukotriene B4 (LTB4). Together, our data provide evidence that FOP plays an important inhibitory role in the recruitment of leukocytes into the joint cavity of arthritic rats. PMID:26378008

  9. Tracking toxic chemicals

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    A new report tracking industrial pollution in North America indicates some good news, in terms of downward trends in the release and transfer of these substances.The July report, which tracks 165 chemicals released in the United States and Canada, shows that the total amount of 3.2 million tonnes of chemical releases and transfers from industrial facilities tracked by the North American Commission for Environmental Cooperation (CEC) decreased by 2% overall from 1995 to 1998.

  10. The removal of morphologically abnormal sperm forms by phagocytes: a positive role for seminal leukocytes?

    PubMed

    Tomlinson, M J; White, A; Barratt, C L; Bolton, A E; Cooke, I D

    1992-04-01

    A preliminary investigation was undertaken further to determine the function of the leukocytic cells found in semen. We performed semen analysis and quantified leukocyte subsets using immunocytochemical staining techniques in ejaculates of 351 patients. Leukocyte profiles were examined in relation to sperm morphological data for evidence of a sperm removal/selection process. Three types of seminal phagocytic cell were found to contain spermatozoa: small polymorphonuclear leukocytes (approximately 10-12 microns), monocytes of similar size and much larger (30-40 microns) macrophages capable of engulfing multiple sperm heads. The total leukocyte count (P less than 0.01), the numbers of phagocytic cells i.e. polymorphonuclear leukocytes (P less than 0.05), monocyte/macrophages (P less than 0.01) and HLA-DR positive cells (P less than 0.01), were significantly higher in those samples with greater than 50% ideal sperm forms. Significantly fewer of these same cell types were observed in samples with greater than 50% head defects. There was no difference in the number of tail or midpiece defects between leukocytospermic (greater than 10(6)/ml) and non-leukocytospermic semen samples. Oligozoospermic samples contained significantly fewer leukocytes (P less than 0.005), although above a concentration of 5 x 10(6)/ml, the sperm number was not correlated with leukocyte number. These data, along with repeated observation of spermatozoa or sperm fragments within phagocytic cells, support the hypothesis that leukocytes have a role in the removal of abnormal spermatozoa from the ejaculate. PMID:1522196

  11. Tracking in anatomic pathology.

    PubMed

    Pantanowitz, Liron; Mackinnon, Alexander C; Sinard, John H

    2013-12-01

    Bar code-based tracking solutions, long present in clinical pathology laboratories, have recently made an appearance in anatomic pathology (AP) laboratories. Tracking of AP "assets" (specimens, blocks, slides) can enhance laboratory efficiency, promote patient safety, and improve patient care. Routing of excess clinical material into research laboratories and biorepositories are other avenues that can benefit from tracking of AP assets. Implementing tracking is not as simple as installing software and turning it on. Not all tracking solutions are alike. Careful analysis of laboratory workflow is needed before implementing tracking to assure that this solution will meet the needs of the laboratory. Such analysis will likely uncover practices that may need to be modified before a tracking system can be deployed. Costs that go beyond simply that of purchasing software will be incurred and need to be considered in the budgeting process. Finally, people, not technology, are the key to assuring quality. Tracking will require significant changes in workflow and an overall change in the culture of the laboratory. Preparation, training, buy-in, and accountability of the people involved are crucial to the success of this process. This article reviews the benefits, available technology, underlying principles, and implementation of tracking solutions for the AP and research laboratory. PMID:23634908

  12. Phytohemagglutinin enhancement of dengue-2 virus replication in nonimmune rhesus monkey peripheral blood leukocytes.

    PubMed Central

    Marchette, N J; Halstead, S B

    1978-01-01

    Phytohemagglutinin treatment of peripheral blood leukocytes from dengue nonimmune monkeys enhanced dengue-2 virus replication. Enhancement was due primarily to an increase in the number of infected cells. Destruction of mononuclear phagocytes with silica did not significantly inhibit virus replication in phytohemagglutinin-treated cultures. Pokeweed mitogen, concanavalin A, and streptolysin O stimulated increased deoxyribonucleic acid synthesis in monkey leukocytes but did not enhance virus replication. None of the mitogens significantly affected virus replication in cultures of dengue-immune monkey peripheral blood leukocytes. PMID:203535

  13. [Change of leukocytic phagocytosis during repeat hemoperfusion with cross-linked agar beads entrapped attapulgite clay].

    PubMed

    Huang, Wei; Ma, Yu; Yang, Xiaolan; Tang, Xianjue; Shu, Changda

    2003-06-01

    The leukocytic phagocytosis rate and the index of phagocytosis of rats on cross-linked agar beads entrapped attapulgite clay (CAA) hemoperfusion were studied. The results revealed that the leukocytic phagocytosis rate and the index of phagocytosis descended significantly after 1 hour and rose gradually after 6 hours. Finally it reached the normal level after 48 hours. Hemoperfusion repeated two times gave similar results. In conclusion, the function of leukocytic phagocytosis declined temporarily during CAA hemoperfusion. Many times hemoperfusion will not notably affect the body's defense system of rats. PMID:12856604

  14. Study of terahertz-radiation-induced DNA damage in human blood leukocytes

    SciTech Connect

    Angeluts, A A; Esaulkov, M N; Kosareva, O G; Solyankin, P M; Shkurinov, A P; Gapeyev, A B; Pashovkin, T N; Matyunin, S N; Nazarov, M M; Cherkasova, O P

    2014-03-28

    We have carried out the studies aimed at assessing the effect of terahertz radiation on DNA molecules in human blood leukocytes. Genotoxic testing of terahertz radiation was performed in three different oscillation regimes, the blood leukocytes from healthy donors being irradiated for 20 minutes with the mean intensity of 8 – 200 μW cm{sup -2} within the frequency range of 0.1 – 6.5 THz. Using the comet assay it is shown that in the selected regimes such radiation does not induce a direct DNA damage in viable human blood leukocytes. (biophotonics)

  15. Study of terahertz-radiation-induced DNA damage in human blood leukocytes

    NASA Astrophysics Data System (ADS)

    Angeluts, A. A.; Gapeyev, A. B.; Esaulkov, M. N.; Kosareva, O. G.; Matyunin, S. N.; Nazarov, M. M.; Pashovkin, T. N.; Solyankin, P. M.; Cherkasova, O. P.; Shkurinov, A. P.

    2014-03-01

    We have carried out the studies aimed at assessing the effect of terahertz radiation on DNA molecules in human blood leukocytes. Genotoxic testing of terahertz radiation was performed in three different oscillation regimes, the blood leukocytes from healthy donors being irradiated for 20 minutes with the mean intensity of 8 - 200 μW cm-2 within the frequency range of 0.1 - 6.5 THz. Using the comet assay it is shown that in the selected regimes such radiation does not induce a direct DNA damage in viable human blood leukocytes.

  16. Radiographic and immunohistochemical analysis of leukocyte adhesion deficiency in Holstein heifers.

    PubMed

    Nagahata, H; Taniyama, H; Izumisawa, Y; Kotani, T; Noda, H; Kociba, G J

    1995-10-01

    Radiographic and immunohistochemical analyses were performed in two Holstein heifers with leukocyte adhesion deficiency (BLAD). Severe bone resorption, osteolysis and severe progressive periodontitis in submandibula due to dysfunction of leukocytes in heifers affected with BLAD were demonstrated by radiographic examination. Immunohistochemical analysis of lymph nodes using anti-CD18 monoclonal antibody demonstrated that CD18-positive cells were not found on those from a heifer affected with BLAD, whereas CD18-positive cells were clearly present in lymph nodes from a clinically normal heifer. These characteristic findings support the importance of adherence-dependent leukocyte functions in host defense. PMID:8548695

  17. The role of nitric oxide in regulation of leukocyte migration into the heart tissue in vitro.

    PubMed

    Petenkova, A A; Kovalenko, R I; Nozdrachev, A D

    2015-11-01

    Characteristics of leukocyte migration have been studied during the incubation of the right and left ventricles of rat heart explants in autologous blood plasma. Within the first 60 min, the leukocyte amount in the medium increases. Moreover, it is associated with cell release from the heart tissue. During further incubation, the cell release decreases; after 3 h of incubation, the cells begin to migrate back into the heart tissue. However, neutrophil migration does not change. Sodium nitrite, being a donor of nitric oxide significantly, reduces the leukocyte migration from the heart explants into the incubation medium, especially from left ventricle explants. PMID:26725240

  18. Kinetics of leukocyte sequestration in the lungs of acutely septic primates: A study using sup 111 In-labeled autologous leukocytes

    SciTech Connect

    Hangen, D.H.; Segall, G.M.; Harney, E.W.; Stevens, J.H.; McDougall, I.R.; Raffin, T.A. )

    1990-03-01

    To further clarify the role of leukocytes in the pathogenesis of ARDS, we studied the localization and kinetics of leukocyte migration using 111In-labeled autologous white cell scans ({sup 111}In wbc scans) in four primates made acutely septic with infusions of Escherichia coli. Whole body images were obtained with a gamma camera and were acquired on computer every 15 min beginning immediately after the E. coli infusion. Simultaneous measurements of C5a and peripheral blood leukocyte count were also obtained. Within 5 min of initiating sepsis, three major events occurred: complement activation as measured by the production of C5a, a profound fall in peripheral leukocyte count, and a significant increase in the sequestration of leukocytes in the lungs. The pulmonary sequestration reached a peak at 15 min with a mean of 152% of baseline activity. This sequestration consisted of a population that was predominantly neutrophils. Damage to the pulmonary capillary endothelium was demonstrated by an increase in extravascular lung water. The results support a role for neutrophils and complement as mediators in the pathogenesis of ARDS.

  19. Detection of aggregated leukocytes in the circulating pool during stress-demargination is not necessarily a result of decreased leukocyte adhesiveness.

    PubMed

    Arber, N; Berliner, S; Rotenberg, Z; Friedman, J; Belagodatni, E; Ostfeld, I; Aronson, M; Pinkhas, J

    1991-01-01

    Leukocyte endothelial interactions are essential for a normal immune response. It is known that this response is influenced by stress and that the latter induces demargination. We examined the question of whether stress demargination results from a decreased state of leukocyte adhesiveness. Included were various volunteers and patients under different degrees of stress. 66 young athletes before beginning their daily exercises, 67 middle-aged healthy volunteers, 25 patients before ergometry for evaluation of chest pain, 75 patients who were referred to the emergency room with chest pain without ischemia/infarction, 78 patients with ischemia/infarction, 65 patients with minor trauma, 25 with a fracture and 12 with polytrauma. The leukocyte adhesiveness/aggregation (LAA) values were measured with a direct slide test. The respective LAA values were 7.4 +/- 4.7, 6.3 +/- 4.4, 5.8 +/- 3.6, 5.2 +/- 3.5, 10.8 +/- 8.5, 9.1 +/- 5.8, 12.2 +/- 6.6 and 19 +/- 12.6% of aggregated leukocytes. We conclude that an increase in aggregated white blood cells can be detected in the circulating pool during major stress. It is therefore suggested that stress demargination is not necessarily a result of diminished leukocyte adhesiveness. PMID:1950357

  20. Fluorescence imaging microscopy of leukocytes-endothelium interaction in rat mesenteric microcirculation after endotoxin injection: role of inhaled nitric oxide

    NASA Astrophysics Data System (ADS)

    Mordon, Serge R.; Neviere, Remi; Marechal, Xavier-Marie; Buys, Bruno; Dhelin, Guy; Lesage, Jean C.; Mathieu, D.; Guery, Benoit; Chopin, Claude

    1999-02-01

    The adhesion of leukocytes to microvascular endothelium has been recognized as an important factor in the development of multiple organ dysfunction after a septic insult. We tested the hypothesis whether inhaled NO would reduce leukocyte rolling and / or leukocyte adhesion in the mesenteric venule preparation in endotoxemic rats. This study was performed with fluorescence imaging microscopy using a closed chamber for in vivo mesentery visualization. Leukocytes were selectively stained with acridine red. Compared to saline, endotoxemia was associated with increases in the flux of rolling leukocytes and in adherent and emigrated leukocytes. Inhaled nitric oxide treatment had no effects on leukocyte behavior in saline treated rats, whereas it reduced adherent and emigrated leukocytes in endotoxin-treated rats. In conclusion, we demonstrated that endotoxemia-induced leukocyte infiltration was related to an increase in the number of rolling leukocytes and subsequent adhesion and emigration in the mesenteric venule. Our results clearly showed that inhaled NO reduces leukocyte adhesion and transmigration in mesenteric venule of endotoxemic rats presumably by interfering with specific cell adhesion molecules.

  1. Systemic leukopenia, evaluation of laminar leukocyte infiltration and laminar lesions in horses with naturally occurring colic syndrome.

    PubMed

    Laskoski, Luciane Maria; Locatelli-Dittrich, Rosangela; Valadão, Carlos Augusto Araújo; Deconto, Ivan; Gonçalves, Kamila Alcala; Montiani-Ferreira, Fabiano; Brum, Juliana Sperotto; de Brito, Harald Fernando Vicente; de Sousa, Renato Silva

    2015-08-01

    The present study was aimed at identifying laminar lesions and leukocyte infiltration in hoof laminar tissue of horses with colic syndrome and its correlation with the total leukocyte count before death. Six healthy horses were used as control group (CG), and eighteen horses with lethal gastrointestinal disease were divided into two groups: leukopenic group (LG) with seven leukopenic horses, and non-leukopenic group (NLG) with 11 horses with total leukocyte count within reference range for the species. Leukocyte infiltration was examined by immunohistochemistry. Laminar lesions were observed in both LG and NLG, with no differences in severity between them. LG showed increase of the leukocyte infiltration in the hoof laminar tissue, when compared to CG and NLG. Horses with severe colic syndrome (LG and NLG) developed intense laminar lesions without clinical signs of laminitis, with increased leukocyte infiltration. However, the LG demonstrated an even higher increase of leukocyte infiltration compared to both CG and NLG. PMID:26267083

  2. Performance measurement of the upgraded D0 central track trigger

    SciTech Connect

    Mommsen, Remigius, K.; /Manchester U. /Fermilab

    2006-12-01

    The D0 experiment was upgraded in spring 2006 to harvest the full physics potential of the Tevatron accelerator at Fermi National Accelerator Laboratory, Batavia, Illinois, USA. It is expected that the peak luminosity delivered by the accelerator will increase to over 300 x 10{sup 30} cm{sup -2} s{sup -1}. One of the upgraded systems is the Central Track Trigger (CTT). The CTT uses the Central Fiber Tracker (CFT) and Preshower detectors to identify central tracks with p{sub T} > 1.5GeV at the first trigger level. Track candidates are formed by comparing fiber hits to predefined track equations. In order to minimize latency, this operation is performed in parallel using combinatorial logic implemented in FPGAs. Limited hardware resources prevented the use of the full granularity of the CFT. This leads to a high fake track rate as the occupancy increases. In order to mitigate the problem, new track-finding hardware was designed and commissioned. We report on the upgrade and the improved performance of the CTT system.

  3. Longitudinal decline of leukocyte telomere length in old age and the association with sex and genetic risk

    PubMed Central

    Berglund, Kari; Reynolds, Chandra A.; Ploner, Alexander; Gerritsen, Lotte; Hovatta, Iiris; Pedersen, Nancy L.; Hägg, Sara

    2016-01-01

    Telomeres are DNA-protein structures at the ends of chromosomes. Leukocyte telomere length (LTL) shortening has been associated with advanced age. However, most studies use cross-sectional data, hence, the aim of our study was to model longitudinal trajectories of LTL attrition across 20 years at old age. Assessments of LTL were done by qPCR in SATSA (Swedish Adoption/Twin Study of Aging; N=636 individuals). Cross-sectional and longitudinal associations with age were estimated, the latter using latent growth curve analysis. A genetic risk score (GRS) for LTL was further assessed and included in the models. We confirmed an inverse cross-sectional association of LTL with age (B=−0.0022 T/S-ratio; 95% CI: −0.0035, −0.0009, p-value=0.0008). Longitudinal LTL analyses adjusted for sex (1598 samples; ≤5 measurements) suggested modest average decline until 69 years of age but accelerating decline after 69 years, with significant inter-individual variation. Women had on average ∼6% T/S-ratio units longer LTL at baseline, and inclusion of the GRS improved the model where four risk alleles was equivalent to the effect size difference between the sexes. In this cohort of old individuals, baseline LTL varied with age, sex and genetic background. The rate of change of LTL accelerated with age and varied considerably between individuals. PMID:27391763

  4. Longitudinal decline of leukocyte telomere length in old age and the association with sex and genetic risk.

    PubMed

    Berglund, Kari; Reynolds, Chandra A; Ploner, Alexander; Gerritsen, Lotte; Hovatta, Iiris; Pedersen, Nancy L; Hägg, Sara

    2016-07-01

    Telomeres are DNA-protein structures at the ends of chromosomes. Leukocyte telomere length (LTL) shortening has been associated with advanced age. However, most studies use cross-sectional data, hence, the aim of our study was to model longitudinal trajectories of LTL attrition across 20 years at old age. Assessments of LTL were done by qPCR in SATSA (Swedish Adoption/Twin Study of Aging; N=636 individuals). Cross-sectional and longitudinal associations with age were estimated, the latter using latent growth curve analysis. A genetic risk score (GRS) for LTL was further assessed and included in the models. We confirmed an inverse cross-sectional association of LTL with age (B=-0.0022 T/S-ratio; 95% CI: -0.0035, -0.0009, p-value=0.0008). Longitudinal LTL analyses adjusted for sex (1598 samples; ≤5 measurements) suggested modest average decline until 69 years of age but accelerating decline after 69 years, with significant inter-individual variation. Women had on average ~6% T/S-ratio units longer LTL at baseline, and inclusion of the GRS improved the model where four risk alleles was equivalent to the effect size difference between the sexes. In this cohort of old individuals, baseline LTL varied with age, sex and genetic background. The rate of change of LTL accelerated with age and varied considerably between individuals. PMID:27391763

  5. Leukocyte telomere length positively correlates with duration of lithium treatment in bipolar disorder patients.

    PubMed

    Squassina, Alessio; Pisanu, Claudia; Congiu, Donatella; Caria, Paola; Frau, Daniela; Niola, Paola; Melis, Carla; Baggiani, Gioia; Lopez, Juan Pablo; Cruceanu, Cristiana; Turecki, Gustavo; Severino, Giovanni; Bocchetta, Alberto; Vanni, Roberta; Chillotti, Caterina; Del Zompo, Maria

    2016-07-01

    Bipolar disorder (BD) has been suggested to be associated with accelerated aging and premature cell senescence. While findings on shorter telomeres in BD are controversial, a recent study showed that long-term lithium treatment correlates with longer telomeres in BD. In our study, we sought to investigate the correlation between leukocyte telomere length (LTL) and long-term lithium treatment in a sample of 200 BD patients characterized for lithium response. We also compared data from two different methods commonly used to measure telomere length, quantitative PCR (qPCR) and quantitative fluorescence in situ hybridization (Q-FISH). We also measured, for the first time, the effect of lithium in vitro on the expression of the telomerase gene in human-derived neural progenitor cells (NPCs). Our findings showed that LTL correlated negatively with age (p=0.0002) and was independent of sex, diagnosis, age at onset, suicidal behavior, number of mood episodes, response to lithium and use of other psychotropic medications. After correcting for age, LTL was positively correlated with lithium treatment duration in patients treated for more than two years (n=150, R=0.17, p=0.037). There was a significant correlation between data measured with qPCR and Q-FISH (p=0.012, R=0.826). Lithium treatment increased telomerase expression in NPCs, though this effect was not statistically significant. Our data support previous findings showing that long-term lithium treatment associates with longer telomeres in BD, though this effect appeared to be independent from clinical response to the treatment. Moreover, we suggested for the first time that lithium increases the expression of telomerase gene in human neural progenitor cells. PMID:27084304

  6. Involvement of activated leukocytes in the regulation of plasma levels of acute phase proteins in microgravity simulation experiments

    NASA Astrophysics Data System (ADS)

    Larina, Olga; Bekker, Anna; Turin-Kuzmin, Alexey

    2016-07-01

    Earth-based studies of microgravity effects showed the induction of the mechanisms of acute phase reaction (APR). APR comprises the transition of stress-sensitive protein kinases of macrophages and other responsive cells into the active state and the phosphorylation of transcription factors which in turn stimulate the production of acute-phase reaction cytokines. Leukocyte activation is accompanied by the acceleration of the formation of oxygen radicals which can serve a functional indice of leukocyte cell state. The series of events at acute phase response result in selective changes in the synthesis of a number of secretory blood proteins (acute phase proteins, APPs) in liver cells thus contributing the recovery of homeostasis state in the organism. Earlier experiment with head-down tilt showed the increase in plasma concentrations of two cytokine mediators of acute phase response, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) being the outcome of the activation of producer cells, foremost, leukocytes. In experiment with 4-day dry immersion chemiluminescent (ChL) reply of the whole blood samples to a test stimulus were studied along with the measurements of plasma levels of APPs, namely, alpha1-antitrypsin (alpha1-AT), alpha1-acid glycoprotein (alpha1-AGP), alpha2-macroglobulin (alpha2-M), ceruloplasmin (Cer), haptoglobin (Hp), C3-complement component (C3), C-reactive protein (CRP). Eight individuals aged 21.2 ± 3.2 years were the test subjects in the investigation. Protein studies showed a noticeable increase in the mean plasma levels of all APPs measured in experiment thus producing the evidence of the activation of acute phase response mechanisms while individual patterns revealed variability during the immersion period. The overall trends were similar to these in the previous immersion series. The augment in the strength of signal in stimulated light emission tests was higher after 1- and 2-day of immersion exposure than before the

  7. Multiple model adaptive tracking of airborne targets

    NASA Astrophysics Data System (ADS)

    Norton, John E.

    1988-12-01

    Over the past ten years considerable work has been accomplished at the Air Force Institute of Technology (AFIT) towards improving the ability of tracking airborne targets. Motivated by the performance advantages in using established models of tracking environment variables within a Kalman filter, an advanced tracking algorithm has been developed based on adaptive estimation filter structures. A multiple model bank of filters that have been designed for various target dynamics, which each accounting for atmospheric disturbance of the Forward Looking Infrared (FLIR) sensor data and mechanical vibrations of the sensor platform, outperforms a correlator tracker. The bank of filters provides the estimation capability to guide the pointing mechanisms of a shared aperture laser/sensor system. The data is provided to the tracking algorithm via an (8 x 8)-pixel tracking Field of View (FOV) from the FLIR image plane. Data at each sample period is compared by an enhanced correlator to a target template. These offsets are measurements to a bank of linear Kalman filters which provide estimates of the target's location in azimuth and elevation coordinates based on a Gauss-Markov acceleration model, and a reduced form of the atmospheric jitter model for the disturbance in the IR wavefront carrying future measurements.

  8. Carp head kidney leukocytes display different patterns of oxygen radical production after stimulation with PAMPs and DAMPs.

    PubMed

    Vera-Jimenez, N I; Nielsen, M E

    2013-10-01

    Wound healing and tissue regeneration are essential mechanisms to ensure the survival and health of any organism. Despite this, only a few studies have been devoted to study tissue regeneration during wound healing in fish. Reactive oxygen species (ROS), in particular hydrogen peroxide, play an important dual role both for promoting tissue repair, but also for eradication of pathogens. This study aims at dissecting the contribution of PAMPs (using β-glucan) and DAMPs in the respiratory burst response of carp head kidney-derived leukocytes, and address their contribution to wound healing processes. Consistent with a pathogen eradication strategy, ROS responses to PAMP stimulation (β-glucan) was fast, vigorous and highly dominated by production of superoxide anion. In contrast, stimulation with DAMPs led to a slow, subtle but long-lasting production of oxygen radicals dominated by hydrogen peroxide. Using an in vitro model of scratch-wounded CCB fibroblast cell cultures and a novel PhotoID proliferation assay, stimulation with low and continuous levels of hydrogen peroxide (5 μM) led to a slight increase in the percentage of wound recovery and thus promoted wound closure. In contrast, high doses of hydrogen peroxide (300 μM) impaired fibroblast scratch-wound recovery and caused cell death. These results elucidate the capacity of hydrogen peroxide to influence the fate of tissue regeneration through the establishment of environments suitable for promoting either tissue regeneration or oxidative stress and thereby potential tissue damage. Direct in vitro stimulation with β-glucans did not impact fibroblast scratch-wound recovery, which further suggests that interaction with tissue-resident leukocytes or other components of the fish immune system are required to induce fibroblast proliferation and thus for the accelerated wound healing promoted by β-glucan stimulation. PMID:23517739

  9. Effect of human polymorphonuclear and mononuclear leukocytes on chromosomal and plasmid DNA of Escherichia coli. Role of acid DNase

    SciTech Connect

    Rozenberg-Arska, M.; van Strijp, J.A.; Hoekstra, W.P.; Verhoef, J.

    1984-05-01

    Phagocytosis and killing by polymorphonuclear and mononuclear leukocytes are important host resistance factors against invading microorganisms. Evidence showing that killing is rapidly followed by degradation of bacterial components is limited. Therefore, we studied the fate of Escherichia coli DNA following phagocytosis of E. coli by polymorphonuclear and mononuclear leukocytes. (/sup 3/H)Thymidine-labeled, unencapsulated E. coli PC2166 and E. coli 048K1 were incubated in serum, washed, and added to leukocytes. Uptake and killing of the bacteria and degradation of DNA were measured. Although phagocytosis and killing by mononuclear leukocytes was less efficient than that by polymorphonuclear leukocytes, only mononuclear leukocytes were able to degrade E. coli PC2166 DNA. Within 2 h, 60% of the radioactivity added to mononuclear leukocytes was released into the supernate, of which 40% was acid soluble. DNA of E. coli 048K1 was not degraded. To further analyze the capacity of mononuclear leukocytes to degrade E. coli DNA, chromosomal and plasmid DNA was isolated from ingested bacteria and subjected to agarose gel-electrophoresis. Only chromosomal DNA was degraded after phagocytosis. Plasmid DNA of E. coli carrying a gene coding for ampicillin resistance remained intact for a 2-h period after ingestion, and was still able to transform recipient E. coli cells after this period. Although we observed no DNA degradation during phagocytosis by polymorphonuclear leukocytes, lysates of both polymorphonuclear and mononuclear leukocytes contained acid-DNase activity with a pH optimum of 4.9. However, the DNase activity of mononuclear leukocytes was 20 times higher than that of polymorphonuclear leukocytes. No difference was observed between DNase activity from polymorphonuclear and mononuclear leukocytes from a chronic granulomatous disease patient with DNase activity from control polymorphonuclear and mononuclear leukocytes.

  10. Can Tracking Improve Learning?

    ERIC Educational Resources Information Center

    Duflo, Esther; Dupas, Pascaline; Kremer, Michael

    2009-01-01

    Tracking students into different classrooms according to their prior academic performance is controversial among both scholars and policymakers. If teachers find it easier to teach a homogeneous group of students, tracking could enhance school effectiveness and raise test scores of both low- and high-ability students. If students benefit from…

  11. On the Wrong Track.

    ERIC Educational Resources Information Center

    Black, Susan

    1992-01-01

    By any measure--student achievement, social development, or democratic values--ability grouping and tracking practices are indefensible and unsupported by research. Tracking allows schools to practice in-school segregation and perpetuate unequal opportunities and unequal socialization within classrooms. Jonathan Kozol's investigation shows how…

  12. Large scale tracking algorithms.

    SciTech Connect

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  13. Explaining cloud chamber tracks

    SciTech Connect

    Broyles, A.A.

    1992-06-16

    The operation of many detection devices is usually explained in terms of the ionization tracks produced by particles despite the fact that the corresponding incident wave functions extended over the entire sensitive regions of the detectors. The mechanisms by which the wave function appears to collapse to a track is analyzed here.

  14. TMDL TRACKING SYSTEM

    EPA Science Inventory

    Resource Purpose:The TMDL Tracking System database contains information on the waters listed under section 303(d) of the Clean Water Act and to track those listed waters through TMDL development. The purpose of the database is to allow EPA, the States/Territories/Tribes, ...

  15. Incentives from Curriculum Tracking

    ERIC Educational Resources Information Center

    Koerselman, Kristian

    2013-01-01

    Curriculum tracking creates incentives in the years before its start, and we should therefore expect test scores to be higher during those years. I find robust evidence for incentive effects of tracking in the UK based on the UK comprehensive school reform. Results from the Swedish comprehensive school reform are inconclusive. Internationally, I…

  16. Track record in meteorites

    NASA Astrophysics Data System (ADS)

    Durrani, S. A.

    1981-02-01

    The use of nuclear-track analysis in meteoritic crystals with reference to several areas of research is reviewed. The applications discussed include: fission-track retention ages and cooling rates of meteoritic parent bodies, cosmic-ray studies, determination of pre-atmospheric sizes of meteorites, and search for superheavy elements.

  17. 2 Tracks for Faculty

    ERIC Educational Resources Information Center

    Wilson, Robin

    2012-01-01

    The academic work force has been transformed over the past several decades, less by design than out of expediency. In 1969, professors who were either tenured or tenure-track made up 78 percent of the faculty. Those working part time made up only 18.5 percent. By 2009, those proportions had almost flipped, with tenured and tenure-track making up…

  18. UWB Tracking Software Development

    NASA Technical Reports Server (NTRS)

    Gross, Julia; Arndt, Dickey; Ngo, Phong; Phan, Chau; Dusl, John; Ni, Jianjun; Rafford, Melinda

    2006-01-01

    An Ultra-Wideband (UWB) two-cluster Angle of Arrival (AOA) tracking prototype system is currently being developed and tested at NASA Johnson Space Center for space exploration applications. This talk discusses the software development efforts for this UWB two-cluster AOA tracking system. The role the software plays in this system is to take waveform data from two UWB radio receivers as an input, feed this input into an AOA tracking algorithm, and generate the target position as an output. The architecture of the software (Input/Output Interface and Algorithm Core) will be introduced in this talk. The development of this software has three phases. In Phase I, the software is mostly Matlab driven and calls C++ socket functions to provide the communication links to the radios. This is beneficial in the early stage when it is necessary to frequently test changes in the algorithm. Phase II of the development is to have the software mostly C++ driven and call a Matlab function for the AOA tracking algorithm. This is beneficial in order to send the tracking results to other systems and also to improve the tracking update rate of the system. The third phase is part of future work and is to have the software completely C++ driven with a graphics user interface. This software design enables the fine resolution tracking of the UWB two-cluster AOA tracking system.

  19. Centrifuge Study of Pilot Tolerance to Acceleration and the Effects of Acceleration on Pilot Performance

    NASA Technical Reports Server (NTRS)

    Creer, Brent Y.; Smedal, Harald A.; Wingrove, Rodney C.

    1960-01-01

    A research program the general objective of which was to measure the effects of various sustained accelerations on the control performance of pilots, was carried out on the Aviation Medical Acceleration Laboratory centrifuge, U.S. Naval Air Development Center, Johnsville, PA. The experimental setup consisted of a flight simulator with the centrifuge in the control loop. The pilot performed his control tasks while being subjected to acceleration fields such as might be encountered by a forward-facing pilot flying an atmosphere entry vehicle. The study was divided into three phases. In one phase of the program, the pilots were subjected to a variety of sustained linear acceleration forces while controlling vehicles with several different sets of longitudinal dynamics. Here, a randomly moving target was displayed to the pilot on a cathode-ray tube. For each combination of acceleration field and vehicle dynamics, pilot tracking accuracy was measured and pilot opinion of the stability and control characteristics was recorded. Thus, information was obtained on the combined effects of complexity of control task and magnitude and direction of acceleration forces on pilot performance. These tests showed that the pilot's tracking performance deteriorated markedly at accelerations greater than about 4g when controlling a lightly damped vehicle. The tentative conclusion was also reached that regardless of the airframe dynamics involved, the pilot feels that in order to have the same level of control over the vehicle, an increase in the vehicle dynamic stability was required with increases in the magnitudes of the acceleration impressed upon the pilot. In another phase, boundaries of human tolerance of acceleration were established for acceleration fields such as might be encountered by a pilot flying an orbital vehicle. A special pilot restraint system was developed to increase human tolerance to longitudinal decelerations. The results of the tests showed that human tolerance

  20. TRACKED VEHICLE Rev 75

    SciTech Connect

    Raby, Eric Y.

    2007-05-08

    Revision 75 of the Tracked Vehicle software is a soft real-time simulation of a differentially steered, tracked mobile robot, which, because of the track flippers, resembles the iRobot PackBot (http://www.irobot.com/). Open source libraries are used for the physics engine (http://www.ode.org/), the display and user interface (http://www.mathies.com/cpw/), and the program command line and configuration file parameters (http://www.boost.org/). The simulation can be controlled by a USB joystick or the keyboard. The configuration file contains demonstration model parameters of no particular vehicle. This simulation can be used as a starting point for those doing tracked vehicle simulations. This simulation software is essentially a research tool which can be modified and adapted for certain types of tracked vehicle research. An open source license allows an individual researchers to tailor the code to their specific research needs.

  1. TRACKED VEHICLE Rev 75

    2007-05-08

    Revision 75 of the Tracked Vehicle software is a soft real-time simulation of a differentially steered, tracked mobile robot, which, because of the track flippers, resembles the iRobot PackBot (http://www.irobot.com/). Open source libraries are used for the physics engine (http://www.ode.org/), the display and user interface (http://www.mathies.com/cpw/), and the program command line and configuration file parameters (http://www.boost.org/). The simulation can be controlled by a USB joystick or the keyboard. The configuration file contains demonstration model parametersmore » of no particular vehicle. This simulation can be used as a starting point for those doing tracked vehicle simulations. This simulation software is essentially a research tool which can be modified and adapted for certain types of tracked vehicle research. An open source license allows an individual researchers to tailor the code to their specific research needs.« less

  2. Quality control in a manual and an automated leukocyte differential count.

    PubMed

    Takubo, T; Tatsumi, N

    1999-01-01

    Quality control (QC) has been introduced in laboratories, and QC surveys in leukocyte differential count to enhance quality have been performed by College of American Pathologists, Japanese Association of Medical Technologists, Osaka Medical Association and manufacturers. The results of QC survey in a manual leukocyte differential count indicated problems on the differentiation of segmented neutrophils and band neutrophils and the detection of pathological blood cells on blood smear. While the results of QC survey in an automated leukocyte differential count performed by same manufacturer with an automated blood cell counter were satisfactory, however, there was a difference in leukocyte differential cell counts among laboratories with other manufacturer's instruments because the synthetic blood material used in QC is an exclusive item for an instrument. It is necessary to further reeducate the medical technologists in order to improve morphological performance, and to standardize the synthetic blood material for compatibility with various automated blood cell counters. PMID:10926263

  3. The potential of the novel leukocyte removal filter in cardiopulmonary bypass.

    PubMed

    Fujii, Yutaka

    2016-01-01

    Cardiopulmonary bypass (CPB) is indispensable for cardiac surgery but leads to systemic inflammatory responses and leukocyte activation, possibly due to blood contact with the surface of the CPB unit, surgical, ischemic reperfusion injury, etc. Systemic inflammatory responses during CPB result in increased morbidity and mortality. Activation of leukocytes is an important part of this process and directly contributes to coagulopathy and hemorrhage. This inflammatory response may contribute to the development of postoperative complications, including myocardial dysfunction, respiratory failure, renal and neurologic dysfunction, altered liver function and ultimately, multiple organ failure. Various pharmacologic and mechanical strategies have been developed to minimize the systemic inflammatory response during CPB. For example, leukocyte removal filters were developed in the 1990s for incorporation into the CPB circuit. However, studies of this approach have yielded conflicting findings. The purpose of this was to review the studies of a novel leukocyte removal filter in patients undergoing CPB. PMID:26613267

  4. Leukocyte Infiltration Triggers Seizure Recurrence in a Rat Model of Temporal Lobe Epilepsy.

    PubMed

    Liu, Zanhua; Wang, Suping; Liu, Jinjie; Wang, Feng; Liu, Yi; Zhao, Yongbo

    2016-06-01

    Epilepsy, which affects about 1 % of the population worldwide, leads to poor prognosis and increased morbidity. However, effective drugs providing satisfactory control on seizure relapse were rare, which encouraged more etiological studies. Whether inflammation is one of key events underlying seizure is in debate. In order to explore the role of inflammatory in the pathogenesis and development of epilepsy, we conducted intra-caudal vein injection of leukocytes to aggravated brain inflammatory process in kainic acid-induced seizure model in this study. The results showed that intravenous administration of activated leukocytes increased the frequency and reduced the latent phase of seizure recurrences in rat models of epileptic seizure, during which leukocyte inflammation, brain-blood barrier damage, and neuron injury were also significantly aggravated, indicating that leukocyte infiltration might facilitate seizure recurrence through aggravating brain inflammation, brain-blood barrier damage, and neuron injury. PMID:27040283

  5. Endothelial CD99 signals through soluble adenylyl cyclase and PKA to regulate leukocyte transendothelial migration

    PubMed Central

    Watson, Richard L.; Buck, Jochen; Levin, Lonny R.; Winger, Ryan C.; Wang, Jing; Arase, Hisashi

    2015-01-01

    CD99 is a critical regulator of leukocyte transendothelial migration (TEM). How CD99 signals during this process remains unknown. We show that during TEM, endothelial cell (EC) CD99 activates protein kinase A (PKA) via a signaling complex formed with the lysine-rich juxtamembrane cytoplasmic tail of CD99, the A-kinase anchoring protein ezrin, and soluble adenylyl cyclase (sAC). PKA then stimulates membrane trafficking from the lateral border recycling compartment to sites of TEM, facilitating the passage of leukocytes across the endothelium. Pharmacologic or genetic inhibition of EC sAC or PKA, like CD99 blockade, arrests neutrophils and monocytes partway through EC junctions, in vitro and in vivo, without affecting leukocyte adhesion or the expression of relevant cellular adhesion molecules. This is the first description of the CD99 signaling pathway in TEM as well as the first demonstration of a role for sAC in leukocyte TEM. PMID:26101266

  6. Chromosome and sperm size of Holsteins with and without bovine leukocyte adhesion deficiency.

    PubMed

    Steinholt, H C; Chandler, J E; Baron, R A; Adkinson, R W

    1994-05-01

    The objective was to evaluate bull differences in chromosomal and spermatozoal areas related to the occurrence of the bovine leukocyte adhesion deficiency syndrome. Lymphocyte chromosomes from 30 Holstein bulls and 2 Holstein heifers were measured using image analysis and computer-enhanced video-microscopy. Spermatozoal head areas from 29 of the 30 bulls were measured. Autosomal rank was based on decreasing area. Average total autosomal areas were not the same across bulls. One group of bulls had significantly smaller average chromosomal areas than the others; this group carried bovine leukocyte adhesion deficiency syndrome. Area measures of spermatozoal heads showed that bulls with bovine leukocyte adhesion deficiency syndrome had significantly larger head areas than normal bulls. Lymphocyte chromosomes from 3 cattle that were homozygous for bovine leukocyte adhesion deficiency syndrome were significantly smaller than chromosomes from syndrome heterozygotes. Carrier identification was improved by the use of autosomal and sperm area measurements in addition to pedigree evaluation. PMID:8046065

  7. Appearance of acute gouty arthritis on indium-111-labeled leukocyte scintigraphy

    SciTech Connect

    Palestro, C.J.; Vega, A.; Kim, C.K.; Swyer, A.J.; Goldsmith, S.J. )

    1990-05-01

    Indium-111-labeled leukocyte scintigraphy was performed on a 66-yr-old male with polyarticular acute gouty arthritis. Images revealed intense labeled leukocyte accumulation in a pattern indistinguishable from septic arthritis, in both knees and ankles, and the metatarsophalangeal joint of both great toes, all of which were involved in the acute gouty attack. Joint aspirate as well as blood cultures were reported as no growth; the patient was treated with intravenous colchicine and ACTH for 10 days with dramatic improvement noted. Labeled leukocyte imaging, repeated 12 days after the initial study, revealed near total resolution of joint abnormalities, concordant with the patient's clinical improvement. This case demonstrates that while acute gouty arthritis is a potential pitfall in labeled leukocyte imaging, in the presence of known gout, it may provide a simple, objective, noninvasive method of evaluating patient response to therapy.

  8. Cystine accumulation and clearance by normal and cystinotic leukocytes exposed to cystine dimethyl ester.

    PubMed Central

    Steinherz, R; Tietze, F; Gahl, W A; Triche, T J; Chiang, H; Modesti, A; Schulman, J D

    1982-01-01

    Upon exposure to 0.25 mM cystine dimethyl ester, normal and cystinotic leukocytes accumulate substantially more intracellular cystine than is present endogenously in cystinotic cells. Leukocytes loaded by exposure to cystine dimethyl ester may have abnormally lucent and distended lysosomes, and the cystine is compartmentalized within the granular fraction of the cells. After the cells are exposed to cystine dimethyl ester, cystine clearance from normal leukocytes is much faster than from cystinotic cells. The ratios of labeled cysteine-N-ethylmaleimide to cystine are also greater in normals than in cystinotics 60 min after termination of loading. No overlap in ranges of cystine clearance half-times or cystine-N-ethylmaleimide to cystine ratios was observed in normal compared to cystinotic leukocytes. Limited experiments with fibroblasts exposed to cystine dimethyl ester suggest a correspondingly prolonged cystine clearance for cystinotic cells. These experiments provide evidence for defective clearance of cystine from cystinotic lysosomes in situ. Images PMID:6956873

  9. Infection in diabetic osteoarthropathy: use of indium-labeled leukocytes for diagnosis

    SciTech Connect

    Maurer, A.H.; Millmond, S.H.; Knight, L.C.; Mesgarzadeh, M.; Siegel, J.A.; Shuman, C.R.; Adler, L.P.; Greene, G.S.; Malmud, L.S.

    1986-10-01

    Indium-111 labeled leukocyte imaging was compared with three-phase skeletal scintigraphy as a means of determining whether osteomyelitis was complicating diabetic osteoarthropathy. Three-phase scintigraphy demonstrated increased activity in both infected and noninfected osteopathic bone, with a sensitivity of 75% and a specificity of 56% for osteomyelitis. Leukocyte imaging had the same sensitivity but was most helpful for excluding infection (specificity, 89%) when three-phase imaging could not. Abnormal leukocyte localization was seen at the primary site of infection in all cases within 4 hours after injection. Disadvantages of leukocyte imaging included long preparation time, low count rates resulting in poor spatial resolution, and absence of bone landmarks, which made it difficult to differentiate soft tissue from bone infection.

  10. Detection of a prosthetic aortic valvular abscess with indium-111-labeled leukocytes

    SciTech Connect

    Oates, E.; Sarno, R.C.

    1988-10-01

    An unsuspected annular abscess at the base of a prosthetic aortic valve in a patient with endocarditis was identified by indium-111-labeled leukocyte scintigraphy alone. This highly sensitive and specific technique expediently demonstrated the surgically proven inflammatory focus.

  11. Effects of height acceleration on Geosat heights

    NASA Technical Reports Server (NTRS)

    Hancock, David W., III; Brooks, Ronald L.; Lockwood, Dennis W.

    1990-01-01

    A radar altimeter tracking loop, such as that utilized by Geosat, produces height errors in the presence of persistent height acceleration h(a). The correction factor for the height error is a function of both the loop feedback parameters and the height acceleration. The correction, in meters, to the sea-surface height (SSH) derived from Geosat is -0.16 h(a), where h(a) is in m/sec per sec. The errors induced by accelerations are produced primarily by changes in along-track geoid slopes. The nearly circular Geosat orbit and dynamic ocean topography produce small h(a) values. One area studied in detail encompasses the Marianas Trench and the Challenger Deep in the west central Pacific Ocean. Histograms of SSH corrections due to range accelerations have also been determined from 24-hour segments of Geosat global data. The findings are that 20 percent of the Geosat measurements have acceleration-induced errors of 2 cm or more, while 8 percent have errors of 3 cm or more.

  12. Vitamin C Prevents Cigarette Smoke-Induced Leukocyte Aggregation and Adhesion to Endothelium in vivo

    NASA Astrophysics Data System (ADS)

    Lehr, Hans-Anton; Frei, Balz; Arfors, Karl-E.

    1994-08-01

    A common feature of cigarette-smoke (CS)-associated diseases such as atherosclerosis and pulmonary emphysema is the activation, aggregation, and adhesion of leukocytes to micro- and macrovascular endothelium. A previous study, using a skinfold chamber model for intravital fluorescence microscopy in awake hamsters, has shown that exposure of hamsters to the smoke generated by one research cigarette elicits the adhesion of fluorescently labeled leukocytes to the endothelium of arterioles and small venules. By the combined use of intravital microscopy and scanning electron microscopy, we now demonstrate in the same animal model that (i) CS-induced leukocyte adhesion is not confined to the microcirculation, but that leukocytes also adhere singly and in clusters to the aortic endothelium; (ii) CS induces the formation in the bloodstream of aggregates between leukocytes and platelets; and (iii) CS-induced leukocyte adhesion to micro- and macrovascular endothelium and leukocyte-platelet aggregate formation are almost entirely prevented by dietary or intravenous pretreatment with the water-soluble antioxidant vitamin C (venules, 21.4 ± 11.0 vs. 149.6 ± 38.7 leukocytes per mm^2, P < 0.01; arterioles, 8.5 ± 4.2 vs. 54.3 ± 21.6 leukocytes per mm^2, P < 0.01; aortas, 0.8 ± 0.4 vs. 12.4 ± 5.6 leukocytes per mm^2, P < 0.01; means ± SD of n = 7 animals, 15 min after CS exposure). No inhibitory effect was observed by pretreatment of the animals with the lipid-soluble antioxidants vitamin E or probucol. The protective effects of vitamin C on CS-induced leukocyte adhesion and aggregation were seen at vitamin C plasma levels (55.6 ± 22.2 μM, n = 7) that can easily be reached in humans by dietary means or supplementation, suggesting that vitamin C effectively contributes to protection from CS-associated cardiovascular and pulmonary diseases in humans.

  13. An epigenomic signature of postprandial hyperglycemia in peripheral blood leukocytes.

    PubMed

    Shim, Sung-Mi; Cho, Yoon-Kyung; Hong, Eun-Jung; Han, Bok-Ghee; Jeon, Jae-Pil

    2016-03-01

    Postprandial hyperglycemia is known to be one of the earliest signs of abnormal glucose homeostasis associated with type 2 diabetes. This study aimed to assess clinical significance of a 1-h postprandial glucose level for the development of diabetes, and identify epigenetic biomarkers of postprandial hyperglycemia. We analyzed clinical data from the oral glucose tolerance tests for healthy subjects (n=4502). The ratio (Glu60/Glu0) of 1-h glucose levels to fasting glucose levels was significantly associated with an insulin sensitive index (QUICKI, quantitative insulin sensitivity check index) (β=0.055, P=1.25E-04) as well as a risk of future pre-diabetic and diabetic conversion. Next, DNA methylation profile analyses of 24 matched pairs of the high and low Glu60/Glu0 ratio subjects showed that specific DNA methylation levels in the promoter region of an olfactory receptor gene (olfactory receptor gene family10 member A4, OR10A4) were associated with the Glu60/Glu0 ratios (β=0.337, P=0.03). Moreover, acute oral glucose challenges decreased the DNA methylation levels of OR10A4 but not the global DNA methylation in peripheral leukocytes of healthy subjects (n=7), indicating that OR10A4 is a specific epigenomic target of postprandial hyperglycemia. This work suggests possible relevance of olfactory receptor genes to an earlier molecular biomarker of peripheral hyperglycemia and diabetic conversion. PMID:26632885

  14. Neisseria gonorrhoeae suppresses the oxidative burst of human polymorphonuclear leukocytes

    PubMed Central

    Criss, Alison K.; Seifert, H. Steven

    2008-01-01

    Symptomatic infection with Neisseria gonorrhoeae (Gc) results in a potent polymorphonuclear leukocyte (PMN)-driven inflammatory response, but the mechanisms by which Gc withstands PMN attack are poorly defined. Here we report that Gc can suppress the PMN oxidative burst, a central component of the PMN antimicrobial arsenal. Primary human PMNs remained viable after exposure to liquid-grown, exponential-phase, opacity-associated protein (Opa)-negative Gc of strains FA1090 and MS11 but did not generate reactive oxygen species (ROS), even after bacterial opsonization. Liquid-grown FA1090 Gc expressing OpaB, an Opa protein previously correlated with PMN ROS production, elicited a minor PMN oxidative burst. PMN ROS production in response to Opa− and OpaB+ Gc was markedly enhanced if bacteria were agar-grown or if liquid-grown bacteria were heat killed. Liquid-grown Opa- Gc inhibited the PMN oxidative burst elicited by isogenic dead bacteria, formylated peptides or Staphylococcus aureus but did not inhibit PMN ROS production by OpaB+ Gc or phorbol esters. Suppression of the oxidative burst required Gc-PMN contact and bacterial protein synthesis but not phagocytosis. These results suggest that viable Gc directly inhibits PMN signaling pathways required for induction of the oxidative burst, which may contribute to gonococcal pathogenesis during inflammatory stages of gonorrheal disease. PMID:18684112

  15. Role of polymorphonuclear leukocytes in silica-induced pulmonary fibrosis.

    PubMed Central

    Adamson, I. Y.; Bowden, D. H.

    1984-01-01

    Silicosis is usually attributed to fibroblast stimulation by secretion of damaged alveolar macrophages (AMs), but the role of polymorphonuclear leukocytes (PMNs) and of continuing cell injury in the pathogenesis has not been fully studied. Mice given intratracheal injections of 2 mg of silica received 3H-thymidine 1 hour before death at intervals to 20 weeks. Cellular populations and lysosomal content of lavage fluids were correlated with morphology, DNA synthesis, and collagen content of the lung. The initial response involved rapid PMN and AM recruitment to the alveoli. Some free particles crossed Type 1 epithelial cells, and silica was found in interstitial macrophages. Focal Type 1 cell damage was rapidly repaired by Type 2 cell proliferation. Although PMN numbers dropped after a few days, they never reached control levels and rose again after 8 weeks; the number of AMs fell to control values from 2 to 8 weeks, then increased again. Glucosaminidase and glucuronidase levels in the lavage fluid were much higher than control levels throughout the study. Increased DNA synthesis by interstitial cells occurred from 2 days to 20 weeks; increased collagen synthesis was found from 4 weeks onward. The continuing inflammatory response of the lung to silica suggests may contribute to fibroblastic stimulation. Images Figure 3 Figure 5 Figure 6 PMID:6486244

  16. Separation and identification of equine leukocyte populations and subpopulations.

    PubMed

    Dutta, S K; Bumgardner, M K; Scott, J C; Myrup, A C

    1981-06-01

    Various methods of separation and identification of major equine leukocyte populations and subpopulations were used. The purity of T and B lymphocytes separated in Sephadex anti-equine F(ab')2 columns was 87% to 99% and 83% of 97%, respectively. The purity of T lymphocytes separated in nylon-wool columns was 89% to 98%. Preparations of B lymphocytes separated in glass-bead columns were 68% to 79% pure. The presence (or absence) of surface immunoglobulin by immunofluorescence was the most consistent and reliable method for the identification of B or T lymphocytes, respectively. However, the erythrocyte-antibody-complement-rosette method for the identification of B cells and the erythrocyte-rosette method for the identification of T cells were not suitable. Monocytes were separated by the adherence method, and the purity, as identified by the latex particle ingestion procedure, was 70% to 78%. Electron microscopy of monocytes stained by peroxidase activity did not identify these cells. The purity of neutrophils obtained by the Ficoll-Hypaque separation method was 95% to 97%. The merits and usefulness of these methods were discussed. PMID:6974519

  17. Defects in the oxidative killing of microorganisms by phagocytic leukocytes.

    PubMed

    Roos, D; Weening, R S

    One of the most important mechanisms of phagocytic killing of ingested microorganisms by leukocytes is the generation of toxic oxygen products. During phagocytosis, neutrophils, as well as monocytes and macrophages, display a strongly increased cell respiration. Quantitatively the most important product of this reaction is hydrogen peroxide. Superoxide is also generated in large amounts, probably as an intermediate in the formation of hydrogen peroxide. Indications exist that singlet oxygen and hydroxyl radicals are also formed in this process. Some of these oxygen products have microbicidal properties by themselves. The effect of hydrogen peroxide is greatly enhanced by the enzyme myeloperoxidase. Several dysfunctions of this sytem are known. In chronic granulomatous disease the enzyme system that produces superoxide is not operative. Thus, no superoxide or hydrogen peroxide is generated, leading to a severely decreased bacterial killing capacity. The exact molecular defects in the X-linked and the autosomal form are as yet undefined. Two variants are also known: lipochrome histiocytosis, with different clinical and histological manifestations, and a 'triggering defect' where only strongly opsonized particles trigger the respiratory burst. Myeloperoxidase deficiency leads to slightly decreased killing capacity, especially for yeasts. In glucose-6-phosphate dehydrogenase deficiency no oxygen radicals or hydrogen peroxide are produced because no equivalents for oxygen reduction can be generated in the hexose-monophosphate shunt. Deficiencies in the glutathione redox system also result in impaired phagocyte function, probably because the cells have to be protected against their own toxic oxygen products. PMID:225141

  18. Role of polymorphonuclear leukocytes in silica-induced pulmonary fibrosis

    SciTech Connect

    Adamson, I.Y.; Bowden, D.H.

    1984-10-01

    Silicosis is usually attributed to fibroblast stimulation by secretion of damaged alveolar macrophages (AMs), but the role of polymorphonuclear leukocytes (PMNs) and of continuing cell injury in the pathogenesis has not been fully studied. Mice given intratracheal injections of 2 mg of silica received 3H-thymidine 1 hour before death at intervals to 20 weeks. Cellular populations and lysosomal content of lavage fluids were correlated with morphology, DNA synthesis, and collagen content of the lung. The initial response involved rapid PMN and AM recruitment to the alveoli. Some free particles crossed Type 1 epithelial cells, and silica was found in interstitial macrophages. Focal Type 1 cell damage was rapidly repaired by Type 2 cell proliferation. Although PMN numbers dropped after a few days, they never reached control levels and rose again after 8 weeks; the number of AMs fell to control values from 2 to 8 weeks, then increased again. Glucosaminidase and glucuronidase levels in the lavage fluid were much higher than control levels throughout the study. Increased DNA synthesis by interstitial cells occurred from 2 days to 20 weeks; increased collagen synthesis was found from 4 weeks onward. The continuing inflammatory response of the lung to silica suggests may contribute to fibroblastic stimulation.

  19. Germinal center B cells and mixed leukocyte reactions

    SciTech Connect

    Monfalcone, A.P.; Kosco, M.H.; Szakal, A.K.; Tew, J.G. )

    1989-09-01

    The present study was undertaken to determine if germinal center (GC) B cells are sufficiently activated to stimulate mixed leukocyte reactions (MLR). Percoll density fractionation and a panning technique with peanut agglutinin (PNA) were used to isolate GC B cells from the lymph nodes of immune mice. The GC B cells were treated with mitomycin C or irradiation and used to stimulate allogeneic or syngeneic splenic T cells in the MLR. Controls included high-density (HD) B cells prepared from spleens of the same mice and HD B cells activated with lipopolysaccharide (LPS) and dextran sulfate. GC B cells bound high amount sof PNA (i.e., PNAhi). Similarly, the LPS-dextran sulfate-activated B cells were PNAhi. Treatment with neuraminidase rendered the PNAlo HD B cells PNAhi. GC B cells and the LPS-dextran sulfate-activated HD B cells stimulated a potent MLR, while the untreated HD B cells did not. However, following neuraminidase treatment, the resulting PNAhi HD B cell population was able to induce an MLR. The PNA marker appeared to be an indicator of stimulatory activity, but incubating the cells with PNA to bind the cell surface ligand did not interfere with the MLR. GC B cells were also capable of stimulating a syngeneic MLR in most experiments although this was not consistently obtained. It appears that germinal centers represent a unique in vivo microenvironment that provides the necessary signals for B cells to become highly effective antigen-presenting cells.

  20. Metabolomics profiling reveals novel markers for leukocyte telomere length.

    PubMed

    Zierer, Jonas; Kastenmüller, Gabi; Suhre, Karsten; Gieger, Christian; Codd, Veryan; Tsai, Pei-Chien; Bell, Jordana; Peters, Annette; Strauch, Konstantin; Schulz, Holger; Weidinger, Stephan; Mohney, Robert P; Samani, Nilesh J; Spector, Tim; Mangino, Massimo; Menni, Cristina

    2016-01-01

    Leukocyte telomere length (LTL) is considered one of the most predictive markers of biological aging. The aim of this study was to identify novel pathways regulating LTL using a metabolomics approach. To this end, we tested associations between 280 blood metabolites and LTL in 3511 females from TwinsUK and replicated our results in the KORA cohort. We furthermore tested significant metabolites for associations with several aging-related phenotypes, gene expression markers and epigenetic markers to investigate potential underlying pathways. Five metabolites were associated with LTL: Two lysolipids, 1-stearoylglycerophosphoinositol (P=1.6×10(-5)) and 1-palmitoylglycerophosphoinositol (P=1.6×10(-5)), were found to be negatively associated with LTL and positively associated with phospholipase A2 expression levels suggesting an involvement of fatty acid metabolism and particularly membrane composition in biological aging. Moreover, two gamma-glutamyl amino acids, gamma-glutamyltyrosine (P=2.5×10(-6)) and gamma-glutamylphenylalanine (P=1.7×10(-5)), were negatively correlated with LTL. Both are products of the glutathione cycle and markers for increased oxidative stress. Metabolites were also correlated with functional measures of aging, i.e. higher blood pressure and HDL cholesterol levels and poorer lung, liver and kidney function. Our results suggest an involvement of altered fatty acid metabolism and increased oxidative stress in human biological aging, reflected by LTL and age-related phenotypes of vital organ systems. PMID:26797767

  1. Metabolomics profiling reveals novel markers for leukocyte telomere length

    PubMed Central

    Zierer, Jonas; Kastenmüller, Gabi; Suhre, Karsten; Gieger, Christian; Codd, Veryan; Tsai, Pei-Chien; Bell, Jordana; Peters, Annette; Strauch, Konstantin; Schulz, Holger; Weidinger, Stephan; Mohney, Robert P.; Samani, Nilesh J.; Spector, Tim; Mangino, Massimo; Menni, Cristina

    2016-01-01

    Leukocyte telomere length (LTL) is considered one of the most predictive markers of biological aging. The aim of this study was to identify novel pathways regulating LTL using a metabolomics approach. To this end, we tested associations between 280 blood metabolites and LTL in 3511 females from TwinsUK and replicated our results in the KORA cohort. We furthermore tested significant metabolites for associations with several aging-related phenotypes, gene expression markers and epigenetic markers to investigate potential underlying pathways. Five metabolites were associated with LTL: Two lysolipids, 1-stearoylglycerophosphoinositol (P=1.6×10−5) and 1-palmitoylglycerophosphoinositol (P=1.6×10−5), were found to be negatively associated with LTL and positively associated with phospholipase A2 expression levels suggesting an involvement of fatty acid metabolism and particularly membrane composition in biological aging. Moreover, two gamma-glutamyl amino acids, gamma-glutamyltyrosine (P=2.5×10−6) and gamma-glutamylphenylalanine (P=1.7×10−5), were negatively correlated with LTL. Both are products of the glutathione cycle and markers for increased oxidative stress. Metabolites were also correlated with functional measures of aging, i.e. higher blood pressure and HDL cholesterol levels and poorer lung, liver and kidney function. Our results suggest an involvement of altered fatty acid metabolism and increased oxidative stress in human biological aging, reflected by LTL and age-related phenotypes of vital organ systems. PMID:26797767

  2. Role of bacteria in leukocyte adhesion deficiency-associated periodontitis.

    PubMed

    Hajishengallis, George; Moutsopoulos, Niki M

    2016-05-01

    Leukocyte adhesion deficiency Type I (LAD-I)-associated periodontitis is an aggressive form of inflammatory bone loss that has been historically attributed to lack of neutrophil surveillance of the periodontal infection. However, this form of periodontitis has proven unresponsive to antibiotics and/or mechanical removal of the tooth-associated biofilm. Recent studies in LAD-I patients and relevant animal models have shown that the fundamental cause of LAD-I periodontitis involves dysregulation of a granulopoietic cytokine cascade. This cascade includes interleukin IL-23 (IL-23) and IL-17 that drive inflammatory bone loss in LAD-I patients and animal models and, moreover, foster a nutritionally favorable environment for bacterial growth and development of a compositionally unique microbiome. Although the lack of neutrophil surveillance in the periodontal pockets might be expected to lead to uncontrolled bacterial invasion of the underlying connective tissue, microbiological analyses of gingival biopsies from LAD-I patients did not reveal tissue-invasive infection. However, bacterial lipopolysaccharide was shown to translocate into the lesions of LAD-I periodontitis. It is concluded that the bacteria serve as initial triggers for local immunopathology through translocation of bacterial products into the underlying tissues where they unleash the dysregulated IL-23-IL-17 axis. Subsequently, the IL-23/IL-17 inflammatory response sustains and shapes a unique local microbiome which, in turn, can further exacerbate inflammation and bone loss in the susceptible host. PMID:26375893

  3. Acoustic and photoacoustic microscopy imaging of single leukocytes

    NASA Astrophysics Data System (ADS)

    Strohm, Eric M.; Moore, Michael J.; Kolios, Michael C.

    2016-03-01

    An acoustic/photoacoustic microscope was used to create micrometer resolution images of stained cells from a blood smear. Pulse echo ultrasound images were made using a 1000 MHz transducer with 1 μm resolution. Photoacoustic images were made using a fiber coupled 532 nm laser, where energy losses through stimulated Raman scattering enabled output wavelengths from 532 nm to 620 nm. The laser was focused onto the sample using a 20x objective, and the laser spot co-aligned with the 1000 MHz transducer opposite the laser. The blood smear was stained with Wright-Giemsa, a common metachromatic dye that differentially stains the cellular components for visual identification. A neutrophil, lymphocyte and a monocyte were imaged using acoustic and photoacoustic microscopy at two different wavelengths, 532 nm and 600 nm. Unique features in each imaging modality enabled identification of the different cell types. This imaging method provides a new way of imaging stained leukocytes, with applications towards identifying and differentiating cell types, and detecting disease at the single cell level.

  4. Effects of lead on the killing mechanisms of polymorphonuclear leukocytes

    SciTech Connect

    Silberstein, C.F.

    1984-01-01

    The effects of lead on the killing mechanisms of rat polymorphonuclear leukocytes (PMN) were investigated, using male Long-Evans rats exposed to 1% lead acetate in the drinking water for varying periods of time to achieve blood lead levels ranging from 20-200 ..mu..g/dl. Studies of PMN bacterial and fungal killing activity, chemotaxis and phagocytosis demonstrated that: 1) bactericidal activity of PMN from rats exposed to lead was not altered; 2) chemotactic activity remained within normal limits; 3) the phagocytic ability of the PMN also remained unaltered. In addition to these normal findings, one major abnormality was demonstrated: a significant decrease in the ability of PMN from rats exposed to lead to kill Candida albicans. This defect was not related to age or to length of exposure. It could not be produced by addition of lead to the test system in vitro. Further investigation revealed significant decreases in PMN glucose-6-phosphate dehydrogenase, catalase, and myeloperoxidase activities. These data support two possible mechanisms for the abnormal fungicidal activity of PMN from lead-exposed rats: decrease in ability to reduce oxygen to active metabolites, or reduction in myeloperoxidase activity due to diminshed synthesis of the heme moiety required for its function.

  5. Leukocyte Homing, Fate, and Function Are Controlled by Retinoic Acid

    PubMed Central

    Guo, Yanxia; Brown, Chrysothemis; Ortiz, Carla; Noelle, Randolph J.

    2015-01-01

    Although vitamin A was recognized as an “anti-infective vitamin” over 90 years ago, the mechanism of how vitamin A regulates immunity is only beginning to be understood. Early studies which focused on the immune responses in vitamin A-deficient (VAD) animals clearly demonstrated compromised immunity and consequently increased susceptibility to infectious disease. The active form of vitamin A, retinoic acid (RA), has been shown to have a profound impact on the homing and differentiation of leukocytes. Both pharmacological and genetic approaches have been applied to the understanding of how RA regulates the development and differentiation of various immune cell subsets, and how RA influences the development of immunity versus tolerance. These studies clearly show that RA profoundly impacts on cell- and humoral-mediated immunity. In this review, the early findings on the complex relationship between VAD and immunity are discussed as well as vitamin A metabolism and signaling within hematopoietic cells. Particular attention is focused on how RA impacts on T-cell lineage commitment and plasticity in various diseases. PMID:25540140

  6. Uptake of antibiotics by human polymorphonuclear leukocyte cytoplasts

    SciTech Connect

    Hand, W.L.; King-Thompson, N.L. , Decatur, GA )

    1990-06-01

    Enucleated human polymorphonuclear leukocytes (PMN cytoplasts), which have no nuclei and only a few granules, retain many of the functions of intact neutrophils. To better define the mechanisms and intracellular sites of antimicrobial agent accumulation in human neutrophils, we studied the antibiotic uptake process in PMN cytoplasts. Entry of eight radiolabeled antibiotics into PMN cytoplasts was determined by means of a velocity gradient centrifugation technique. Uptakes of these antibiotics by cytoplasts were compared with our findings in intact PMN. Penicillin entered both intact PMN and cytoplasts poorly. Metronidazole achieved a concentration in cytoplasts (and PMN) equal to or somewhat less than the extracellular concentration. Chloramphenicol, a lipid-soluble drug, and trimethoprim were concentrated three- to fourfold by cytoplasts. An unusual finding was that trimethroprim, unlike other tested antibiotics, was accumulated by cytoplasts more readily at 25 degrees C than at 37 degrees C. After an initial rapid association with cytoplasts, cell-associated imipenem declined progressively with time. Clindamycin and two macrolide antibiotics (roxithromycin, erythromycin) were concentrated 7- to 14-fold by cytoplasts. This indicates that cytoplasmic granules are not essential for accumulation of these drugs. Adenosine inhibited cytoplast uptake of clindamycin, which enters intact phagocytic cells by the membrane nucleoside transport system. Roxithromycin uptake by cytoplasts was inhibited by phagocytosis, which may reduce the number of cell membrane sites available for the transport of macrolides. These studies have added to our understanding of uptake mechanisms for antibiotics which are highly concentrated in phagocytes.

  7. Characterization of Leukocyte Formin FMNL1 Expression in Human Tissues.

    PubMed

    Gardberg, Maria; Heuser, Vanina D; Iljin, Kristiina; Kampf, Caroline; Uhlen, Mathias; Carpén, Olli

    2014-04-01

    Formins are cytoskeleton regulating proteins characterized by a common FH2 structural domain. As key players in the assembly of actin filaments, formins direct dynamic cytoskeletal processes that influence cell shape, movement and adhesion. The large number of formin genes, fifteen in the human, suggests distinct tasks and expression patterns for individual family members, in addition to overlapping functions. Several formins have been associated with invasive cell properties in experimental models, linking them to cancer biology. One example is FMNL1, which is considered to be a leukocyte formin and is known to be overexpressed in lymphomas. Studies on FMNL1 and many other formins have been hampered by a lack of research tools, especially antibodies suitable for staining paraffin-embedded formalin-fixed tissues. Here we characterize, using bioinformatics tools and a validated antibody, the expression pattern of FMNL1 in human tissues and study its subcellular distribution. Our results indicate that FMNL1 expression is not restricted to hematopoietic tissues and that neoexpression of FMNL1 can be seen in epithelial cancer. PMID:24700756

  8. Characterization of Leukocyte Formin FMNL1 Expression in Human Tissues

    PubMed Central

    Heuser, Vanina D.; Iljin, Kristiina; Kampf, Caroline; Uhlen, Mathias; Carpén, Olli

    2014-01-01

    Formins are cytoskeleton regulating proteins characterized by a common FH2 structural domain. As key players in the assembly of actin filaments, formins direct dynamic cytoskeletal processes that influence cell shape, movement and adhesion. The large number of formin genes, fifteen in the human, suggests distinct tasks and expression patterns for individual family members, in addition to overlapping functions. Several formins have been associated with invasive cell properties in experimental models, linking them to cancer biology. One example is FMNL1, which is considered to be a leukocyte formin and is known to be overexpressed in lymphomas. Studies on FMNL1 and many other formins have been hampered by a lack of research tools, especially antibodies suitable for staining paraffin-embedded formalin-fixed tissues. Here we characterize, using bioinformatics tools and a validated antibody, the expression pattern of FMNL1 in human tissues and study its subcellular distribution. Our results indicate that FMNL1 expression is not restricted to hematopoietic tissues and that neoexpression of FMNL1 can be seen in epithelial cancer. PMID:24700756

  9. Drug addiction is associated with leukocyte telomere length

    PubMed Central

    Yang, Zhaoyang; Ye, Junyi; Li, Candong; Zhou, Daizhan; Shen, Qin; Wu, Ji; Cao, Lan; Wang, Ting; Cui, Daxiang; He, Shigang; Qi, Guoyang; He, Lin; Liu, Yun

    2013-01-01

    Telomeres are protective chromosomal structures that play a key role in preserving genomic stability. Telomere length is known to be associated with ageing and age-related diseases. To study the impairment of telomeres induced by drug abuse, we conducted an association study in the Chinese Han population. Multivariate linear regression analyses were performed to evaluate the correlation of leukocyte telomere length (LTL) with addiction control status adjusted for age and gender. The results showed that drug abusers exhibited significantly shorter LTLs than controls (P = 1.32e−06). The time before relapse also presented an inverse correlation with LTL (P = 0.02). Drug abusers who had used heroin and diazepam displayed a shorter LTL than those taking other drugs (P = 0.018 and P = 0.009, respectively). Drug abusers who had ingested drugs via snuff exhibited longer LTLs than those using other methods (P = 0.02). These observations may offer a partial explanation for the effects of drug addiction on health. PMID:23528991

  10. The Human Leukocyte Antigen–presented Ligandome of B Lymphocytes*

    PubMed Central

    Hassan, Chopie; Kester, Michel G. D.; de Ru, Arnoud H.; Hombrink, Pleun; Drijfhout, Jan Wouter; Nijveen, Harm; Leunissen, Jack A. M.; Heemskerk, Mirjam H. M.; Falkenburg, J. H. Frederik; van Veelen, Peter A.

    2013-01-01

    Peptides presented by human leukocyte antigen (HLA) molecules on the cell surface play a crucial role in adaptive immunology, mediating the communication between T cells and antigen presenting cells. Knowledge of these peptides is of pivotal importance in fundamental studies of T cell action and in cellular immunotherapy and transplantation. In this paper we present the in-depth identification and relative quantification of 14,500 peptide ligands constituting the HLA ligandome of B cells. This large number of identified ligands provides general insight into the presented peptide repertoire and antigen presentation. Our uniquely large set of HLA ligands allowed us to characterize in detail the peptides constituting the ligandome in terms of relative abundance, peptide length distribution, physicochemical properties, binding affinity to the HLA molecule, and presence of post-translational modifications. The presented B-lymphocyte ligandome is shown to be a rich source of information by the presence of minor histocompatibility antigens, virus-derived epitopes, and post-translationally modified HLA ligands, and it can be a good starting point for solving a wealth of specific immunological questions. These HLA ligands can form the basis for reversed immunology approaches to identify T cell epitopes based not on in silico predictions but on the bona fide eluted HLA ligandome. PMID:23481700

  11. Inhibitory leukocyte immunoglobulin-like receptors in cancer development.

    PubMed

    Zhang, FeiFei; Zheng, JunKe; Kang, XunLei; Deng, Mi; Lu, ZhiGang; Kim, Jaehyup; Zhang, ChengCheng

    2015-12-01

    Inhibitory leukocyte immunoglobulin-like receptors (LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs (ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6 (PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6 (PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase (SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors. PMID:26566804

  12. Neuronal migration and molecular conservation with leukocyte chemotaxis

    PubMed Central

    Rao, Yi; Wong, Kit; Ward, Michael; Jurgensen, Claudia; Wu, Jane Y.

    2007-01-01

    Cell migration is essential in species ranging from bacteria to humans (for recent reviews, see Lauffenburger and Horwitz 1996; Mitchison and Cramer 1996; Montell 1999). In the amoebae Dictyostelium discoideum, cell migration is involved in chemotaxis toward food sources and in aggregation (for review, see Devreotes and Zigmond 1988; Parent and Devreotes 1999; Chung et al. 2001). In higher vertebrates, cell migration plays crucial roles in multiple physiological and pathological processes. During embryonic and neonatal development, cell migration is crucial in morphogenetic processes such as gastrulation, cardiogenesis, and the formation of the nervous system (for review, see Hatten and Mason 1990; Rakic 1990; Hatten and Heintz 1998; Bentivoglio and Mazzarello 1999). In adult animals, cell migration is required for leukocyte trafficking and inflammatory responses (for review, see McCutcheon 1946; Harris 1954; Devreotes and Zigmond 1988). In tumoriogenesis, tumor-induced angiogenesis and tumor metastasis both involve cell migration. Although it is well known that cell migration is necessary for all these processes, our understanding of mechanisms controlling cell migration is still limited. Here we briefly review the significance of neuronal migration and focus on recent studies on the directional guidance of neuronal migration, discussing the possibility that guidance mechanisms for neurons are conserved with those for other somatic cells. PMID:12464628

  13. Association between Leukocyte and Metabolic Syndrome in Urban Han Chinese: A Longitudinal Cohort Study

    PubMed Central

    Zhang, Qian; Song, Xinhong; Lin, Haiyan; Zhang, Dongzhi; Zhang, Yongyuan; Zhu, Zhenxin; Wu, Shuo; Liu, Yanxun; Tang, Fang; Yang, Xiaowei; Xue, Fuzhong

    2012-01-01

    Background Although cross-sectional studies have shown that leukocyte is linked with metabolic syndrome (MetS), few longitudinal or cohort studies have been used to confirm this relationship. We therefore conducted a large-scale health check-up longitudinal cohort in urban Chinese population from middle to upper socioeconomic strata to investigate and prove the association between the total leukocyte/its subtypes and MetS/its components (obesity, hyperglycemia, dyslipidemia, and hypertension). Methods A longitudinal cohort study was established in 2005 on individuals who were middle-to-upper class urban Chinese. Data used in this investigation was based on 6,513 participants who had at least three routine health check-ups over a period of six-year follow-up. Data analysis was conducted through generalized estimating equation (GEE) model. Results A total of 255 cases of MetS occurred over the six-year follow-up, leading to a total incidence density of 11.45 per 1,000 person-years (255/22279 person-years). The total leukocyte was markedly associated with MetS (RR = 2.66, 95%CI = 1.81–3.90], p<0.0001) and a dose-response existed. Similar trends can be found in monocytes, lymphocytes, and neutrophils compared with the total leukocyte. The total leukocyte, neutrophil, monocyte and eosinophil levels were strong and independent risk factors to obesity, total leukocyte and neutrophil to dyslipidemia and hyperglycemia, while neither total leukocyte nor its subtypes to hypertension. Conclusion Total leukocyte/its subtype were associated with MetS/its components (obesity, dyslipidemia and hyperglycemia), they might provide convenient and useful markers for further risk appraisal of MetS, and be the earlier biomarkers for predicting cardiovascular disease than the components of MetS. PMID:23209610

  14. In-111 labeled leukocyte scintigraphy in a case of multifocal candidiasis

    SciTech Connect

    Palestro, C.J.; Vega, A.; Kim, C.K.; Goldsmith, S.J. )

    1990-06-01

    The value of indium-111 labeled leukocyte scintigraphy for the diagnosis of infection in the general population is well documented; there is less information available on its role in the evaluation of the immunocompromised patient. In this study, leukocyte scintigraphy was performed on a 31-year-old immunocompromised woman who had a possible intra-abdominal abscess. No abscess was detected, but intense oral, esophageal, gastric, and vaginal uptake was observed. Candida infection was histologically confirmed at all four sites.

  15. Assessing leukocyte-endothelial interactions under flow conditions in an ex vivo autoperfused microflow chamber assay.

    PubMed

    Mulki, Lama; Sweigard, J Harry; Connor, Kip M

    2014-01-01

    Leukocyte-endothelial interactions are early and critical events in acute and chronic inflammation and can, when dysregulated, mediate tissue injury leading to permanent pathological damage. Existing conventional assays allow the analysis of leukocyte adhesion molecules only after the extraction of leukocytes from the blood. This requires the blood to undergo several steps before peripheral blood leukocytes (PBLs) can be ready for analysis, which in turn can stimulate PBLs influencing the research findings. The autoperfused micro flow chamber assay, however, allows scientists to study early leukocytes functional dysregulation using the systemic flow of a live mouse while having the freedom of manipulating a coated chamber. Through a disease model, the functional expression of leukocyte adhesion molecules can be assessed and quantified in a micro-glass chamber coated with immobilized endothelial adhesion molecules ex vivo. In this model, the blood flows between the right common carotid artery and left external jugular vein of a live mouse under anesthesia, allowing the interaction of native PBLs in the chamber. Real-time experimental analysis is achieved with the assistance of an intravital microscope as well as a Harvard Apparatus pressure device. The application of a flow regulator at the input point of the glass chamber allows comparable physiological flow conditions amongst the experiments. Leukocyte rolling velocity is the main outcome and is measured using the National Institutes of Health open-access software ImageJ. In summary, the autoperfused micro flow chamber assay provides an optimal physiological environment to study leukocytes endothelial interaction and allows researchers to draw accurate conclusions when studying inflammation. PMID:25590688

  16. Combined leukocyte and bone imaging used to evaluate diabetic osteoarthropathy and osteomyelitis

    SciTech Connect

    Splittgerber, G.F.; Spiegelhoff, D.R.; Buggy, B.P.

    1989-03-01

    Six diabetic patients with roentgenographic finding of osteomyelitis, osteoarthropathy, or both, had combined leukocyte and bone imaging. Bone images demonstrated increased activity in all cases, including three without osteomyelitis. Leukocyte images, however, showed increased activity in only the three cases of osteomyelitis. There was minimal or no activity in the other three cases where osteoarthropathy was ultimately believed to be the basis of the roentgenographic and bone imaging changes.

  17. The role of platelets in the recruitment of leukocytes during vascular disease

    PubMed Central

    Ed Rainger, G.; Chimen, Myriam; Harrison, Matthew J.; Yates, Clara M.; Harrison, Paul; Watson, Stephen P.; Lordkipanidzé, Marie; Nash, Gerard B.

    2015-01-01

    Abstract Besides their role in the formation of thrombus during haemostasis, it is becoming clear that platelets contribute to a number of other processes within the vasculature. Indeed, the integrated function of the thrombotic and inflammatory systems, which results in platelet-mediated recruitment of leukocytes, is now considered to be of great importance in the propagation, progression and pathogenesis of atherosclerotic disease of the arteries. There are three scenarios by which platelets can interact with leukocytes: (1) during haemostasis, when platelets adhere to and are activated on sub-endothelial matrix proteins exposed by vascular damage and then recruit leukocytes to a growing thrombus. (2) Platelets adhere to and are activated on stimulated endothelial cells and then bridge blood borne leukocytes to the vessel wall and. (3) Adhesion between platelets and leukocytes occurs in the blood leading to formation of heterotypic aggregates prior to contact with endothelial cells. In the following review we will not discuss leukocyte recruitment during haemostasis, as this represents a physiological response to tissue trauma that can progress, at least in its early stages, in the absence of inflammation. Rather we will deal with scenarios 2 and 3, as these pathways of platelet–leukocyte interactions are important during inflammation and in chronic inflammatory diseases such as atherosclerosis. Indeed, these interactions mean that leukocytes possess means of adhesion to the vessel wall under conditions that may not normally be permissive of leukocyte–endothelial cell adhesion, meaning that the disease process may be able to bypass the regulatory pathways which would ordinarily moderate the inflammatory response. PMID:26196409

  18. Defect of In Vitro Digestive Ability of Polymorphonuclear Leukocytes in Paracoccidioidomycosis

    PubMed Central

    Goihman-Yahr, Mauricio; Essenfeld-Yahr, Ervin; De Albornoz, María C.; Yarzábal, Luis; De Gómez, MaríA H.; Martín, Blanca San; Ocanto, Ana; Gil, Francisco; Convit, Jacinto

    1980-01-01

    Selected functions of polymorphonuclear leukocytes were studied in patients with paracoccidioidomycosis (South American blastomycosis), in healthy control individuals, and in patients with diseases unrelated to paracoccidioidomycosis. Patients with paracoccidioidomycosis were also evaluated by standard immunological techniques. Phagocytosis and digestion of Paracoccidioides brasiliensis yeastlike cells in vitro was estimated by an original method. It was based on the appearance of phagocytosed P. brasiliensis in preparations stained by a modification of the Papanicolaou method and examined with phase-contrast optics. Interpretation of such findings was confirmed by electron microscopy. Two strains of P. brasiliensis were used. Strain 8506 was freshly isolated from a patient. Strain Pb9 was known to be nonpathogenic and to have a peculiar cell wall composition. Yeastlike cells of the Pb9 strain were digested significantly better than those of strain 8506. A higher number of leukocytes per fungus cells led to a higher proportion of digested P. brasiliensis. Leukocytes from patients with paracoccidioidomycosis phagocytosed the fungus in a normal way, but had a significant lower ability to digest it in vitro. When individual cases were analyzed, there was an excellent correlation between clinical evolution and digestive ability of polymorphonuclear leukocytes. There was good correlation between both of these and immunological parameters. Leukocytes from all groups behaved comparably in tests of general leukocyte function and in their abilities to kill and digest Candida albicans. Our results indicate that, as a group, polymorphonuclear leukocytes from patients with paracoccidioidomycosis had a significant, rather specific, defect in their in vitro digestive capacity against phagocytosed P. brasiliensis. There was also an inverse correlation between strain pathogenicity and its susceptibility to in vitro digestion by polymorphonuclear leukocytes. Our findings are

  19. Indium-111 leukocyte scintigraphic detection of myocardial abscess formation in patients with endocarditis

    SciTech Connect

    Cerqueira, M.D.; Jacobson, A.F.

    1989-05-01

    Myocardial abscess formation in patients with bacterial endocarditis in most clinical settings, especially in patients with prosthetic valves, is a primary indicator for surgical valve replacement. We report the detection of myocardial abscesses using /sup 111/In leukocyte scintigraphy in three patients with prosthetic or native valve endocarditis and nondiagnostic echocardiograms. Leukocyte scintigraphy may allow identification of myocardial abscess formation earlier than other imaging modalities.

  20. Laser driven ion accelerator

    DOEpatents

    Tajima, Toshiki

    2006-04-18

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  1. Laser driven ion accelerator

    DOEpatents

    Tajima, Toshiki

    2005-06-14

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  2. Immunosuppressive Drugs Affect High-Mannose/Hybrid N-Glycans on Human Allostimulated Leukocytes

    PubMed Central

    Pocheć, Ewa; Bocian, Katarzyna; Ząbczyńska, Marta; Korczak-Kowalska, Grażyna; Lityńska, Anna

    2015-01-01

    N-glycosylation plays an important role in the majority of physiological and pathological processes occurring in the immune system. Alteration of the type and abundance of glycans is an element of lymphocyte differentiation; it is also common in the development of immune-mediated inflammatory diseases. The N-glycosylation process is very sensitive to different environmental agents, among them the pharmacological environment of immunosuppressive drugs. Some results show that high-mannose oligosaccharides have the ability to suppress different stages of the immune response. We evaluated the effects of cyclosporin A (CsA) and rapamycin (Rapa) on high-mannose/hybrid-type glycosylation in human leukocytes activated in a two-way mixed leukocyte reaction (MLR). CsA significantly reduced the number of leukocytes covered by high-mannose/hybrid N-glycans, and the synergistic action of CsA and Rapa led to an increase of these structures on the remaining leukocytes. This is the first study indicating that β1 and β3 integrins bearing high-mannose/hybrid structures are affected by Rapa and CsA. Rapa taken separately and together with CsA changed the expression of β1 and β3 integrins and, by regulating the protein amount, increased the oligomannose/hybrid-type N-glycosylation on the leukocyte surface. We suggest that the changes in the glycosylation profile of leukocytes may promote the development of tolerance in transplantation. PMID:26339568

  3. Dynamic properties of blood flow and leukocyte mobilization in infected flaps

    SciTech Connect

    Feng, L.J.; Price, D.C.; Mathes, S.J.; Hohn, D. )

    1990-11-01

    Two aspects of the inflammatory response to infection--blood flow alteration and leukocyte mobilization--are investigated in the canine model. The elevation of paired musculocutaneous (MC) and random pattern (RP) flaps allowed comparison of healing flaps with significant differences in blood flow (lower in random pattern flaps) and resistance to infection (greater in musculocutaneous flaps). Blood flow changes as determined by radioactive xenon washout were compared in normal skin and distal flap skin both after elevation and following bacterial inoculation. Simultaneous use of In-111 labeled leukocytes allowed determination of leukocyte mobilization and subsequent localization in response to flap infection. Blood flow significantly improved in the musculocutaneous flap in response to infection. Although total leukocyte mobilization in the random pattern flap was greater, the leukocytes in the musculocutaneous flap were localized around the site of bacterial inoculation within the dermis. Differences in the dynamic blood flow and leukocyte mobilization may, in part, explain the greater reliability of musculocutaneous flaps when transposed in the presence of infection.

  4. Molecular basis of leukocyte-endothelium interactions during the inflammatory response.

    PubMed

    Barreiro, Olga; Sánchez-Madrid, Francisco

    2009-05-01

    The process of leukocyte extravasation, a critical step in the inflammatory response, involves the migration of leukocytes from the bloodstream towards target tissues, where they exert their effector function. Leukocyte extravasation is orchestrated by the combined action of cellular adhesion receptors and chemotactic factors, and involves radical morphological changes in both leukocytes and endothelial cells. Thus, it constitutes an active process for both cell types and promotes the rapid and efficient influx of leukocytes to inflammatory foci without compromising the integrity of the endothelial barrier. This article provides a review of leukocyte extravasation from both molecular and mechanical points of view, with a particular emphasis on the most recent findings on the topic. It includes a description of newly revealed steps in the adhesion cascade, such as slow rolling motion, intraluminal crawling and alternative pathways for transcellular migration, and discusses the functional role of novel adhesion receptors, the spatiotemporal organization of receptors at the plasma membrane and the signaling pathways that control different phases of the extravasation process. PMID:19406069

  5. Genomic Copy Number Variations in the Genomes of Leukocytes Predict Prostate Cancer Clinical Outcomes

    PubMed Central

    Huo, Zhiguang; Martin, Amantha; Nelson, Joel B.; Tseng, George C.; Luo, Jian-Hua

    2015-01-01

    Accurate prediction of prostate cancer clinical courses remains elusive. In this study, we performed whole genome copy number analysis on leukocytes of 273 prostate cancer patients using Affymetrix SNP6.0 chip. Copy number variations (CNV) were found across all chromosomes of the human genome. An average of 152 CNV fragments per genome was identified in the leukocytes from prostate cancer patients. The size distributions of CNV in the genome of leukocytes were highly correlative with prostate cancer aggressiveness. A prostate cancer outcome prediction model was developed based on large size ratio of CNV from the leukocyte genomes. This prediction model generated an average prediction rate of 75.2%, with sensitivity of 77.3% and specificity of 69.0% for prostate cancer recurrence. When combined with Nomogram and the status of fusion transcripts, the average prediction rate was improved to 82.5% with sensitivity of 84.8% and specificity of 78.2%. In addition, the leukocyte prediction model was 62.6% accurate in predicting short prostate specific antigen doubling time. When combined with Gleason’s grade, Nomogram and the status of fusion transcripts, the prediction model generated a correct prediction rate of 77.5% with 73.7% sensitivity and 80.1% specificity. To our knowledge, this is the first study showing that CNVs in leukocyte genomes are predictive of clinical outcomes of a human malignancy. PMID:26295840

  6. Microfluidic Leukocyte Isolation for Gene Expression Analysis in Critically Ill Hospitalized Patients

    PubMed Central

    Russom, Aman; Sethu, Palaniappan; Irimia, Daniel; Mindrinos, Michael N.; Calvano, Steve E.; Garcia, Iris; Finnerty, Celeste; Tannahill, Cynthia; Abouhamze, Amer; Wilhelmy, Julie; López, M. Cecilia; Baker, Henry V.; Herndon, David N.; Lowry, Stephen F.; Maier, Ronald V.; Davis, Ronald W.; Moldawer, Lyle L.; Tompkins, Ronald G.; Toner, Mehmet

    2014-01-01

    BACKGROUND Microarray technology is becoming a powerful tool for diagnostic, therapeutic, and prognostic applications. There is at present no consensus regarding the optimal technique to isolate nucleic acids from blood leukocyte populations for subsequent expression analyses. Current collection and processing techniques pose significant challenges in the clinical setting. Here, we report the clinical validation of a novel microfluidic leukocyte nucleic acid isolation technique for gene expression analysis from critically ill, hospitalized patients that can be readily used on small volumes of blood. METHODS We processed whole blood from hospitalized patients after burn injury and severe blunt trauma according to the microfluidic and standard macroscale leukocyte isolation protocol. Side-by-side comparison of RNA quantity, quality, and genome-wide expression patterns was used to clinically validate the microfluidic technique. RESULTS When the microfluidic protocol was used for processing, sufficient amounts of total RNA were obtained for genome-wide expression analysis from 0.5 mL whole blood. We found that the leukocyte expression patterns from samples processed using the 2 protocols were concordant, and there was less variability introduced as a result of harvesting method than there existed between individuals. CONCLUSIONS The novel microfluidic approach achieves leukocyte isolation in <25 min, and the quality of nucleic acids and genome expression analysis is equivalent to or surpasses that obtained from macroscale approaches. Microfluidics can significantly improve the isolation of blood leukocytes for genomic analyses in the clinical setting. PMID:18375483

  7. A silent chemokine receptor regulates steady-state leukocyte homing in vivo.

    PubMed

    Heinzel, Kornelia; Benz, Claudia; Bleul, Conrad C

    2007-05-15

    The location of leukocytes in different microenvironments is intimately connected to their function and, in the case of leukocyte precursors, to the executed differentiation and maturation program. Leukocyte migration within lymphoid organs has been shown to be mediated by constitutively expressed chemokines, but how the bioavailability of these homeostatic chemokines is regulated remains unknown. Here, we report in vivo evidence for the role of a nonsignaling chemokine receptor in the migration of leukocytes under physiological, i.e., noninflammatory, conditions. We have studied the in vivo role of the silent chemokine receptor CCX-CKR1 by both loss- and gain-of-function approaches. CCX-CKR1 binds the constitutively expressed chemokines CC chemokine ligand (CCL)19, CCL21, and CCL25. We find that CCX-CKR1 is involved in the steady-state homing of CD11c(+)MHCII(high) dendritic cells to skin-draining lymph nodes, and it affects the homing of embryonic thymic precursors to the thymic anlage. These observations indicate that the silent chemokine receptor CCX-CKR1, which is exclusively expressed by stroma cells, but not hematopoietic cells themselves, regulates homeostatic leukocyte migration by controlling the availability of chemokines in the extracellular space. This finding adds another level of complexity to our understanding of leukocyte homeostatic migration. PMID:17485674

  8. Observing a fictitious stressful event: haematological changes, including circulating leukocyte activation.

    PubMed

    Mian, Rubina; Shelton-Rayner, Graham; Harkin, Brendan; Williams, Paul

    2003-03-01

    The aim of this study was to assess the effect of watching a psychological stressful event on the activation of leukocytes in healthy human volunteers. Blood samples were obtained from 32 healthy male and female subjects aged between 20 and 26 years before, during and after either watching an 83-minute horror film that none of the subjects had previously seen (The Texas Chainsaw Massacre, 1974) or by sitting quietly in a room (control group). Total differential cell counts, leukocyte activation as measured by the nitroblue tetrazolium (NBT) test, heart rate and blood pressure (BP) measurements were taken at defined time points. There were significant increases in peripheral circulating leukocytes, the number of activated circulating leukocytes, haemoglobin (Hb) concentration and haematocrit (Hct) in response to the stressor. These were accompanied by significant increases in heart rate, systolic and diastolic BP (P<0.05 from baseline). This is the first reported study on the effects of observing a psychologically stressful, albeit fictitious event on circulating leukocyte numbers and the state of leukocyte activation as determined by the nitrotetrazolium test. PMID:12637206

  9. Elevated TREM2 mRNA expression in leukocytes in schizophrenia but not major depressive disorder.

    PubMed

    Yoshino, Yuta; Kawabe, Kentaro; Yamazaki, Kiyohiro; Watanabe, Shinya; Numata, Shusuke; Mori, Yoko; Yoshida, Taku; Iga, Junichi; Ohmori, Tetsuro; Ueno, Shu-Ichi

    2016-06-01

    The pathological mechanisms of schizophrenia (SCZ) have not been clarified, but the microglia hypothesis has recently been discussed. We previously reported that the mRNA for a protein related to activation of microglia, triggering receptor expressed on myeloid cell 2 (TREM2), is expressed higher in peripheral leukocytes in SCZ than controls. In this study, we analyzed TREM2 mRNA expression in leukocytes from both SCZ and major depressive disorder (MDD) patients. We compared 50 SCZ patients and 42 MDD patients with age-matched controls. Levels of TREM2 mRNA in leukocytes were analyzed with quantitative real-time PCR method using TaqMan probe. TREM2 mRNA expression was significantly higher in leukocytes of SCZ subjects than controls, but the expression level was non-significantly different in MDD subjects. We observed a decrease in TREM2 mRNA expression in leukocytes from one SCZ patient after clozapine treatment. The expression did not change following ECT, but the expression level in this patient was still significantly higher than that in controls. We conclude that the high amount of TREM2 mRNA expression in leukocytes is specific to SCZ but not MDD and that changes in TREM2 mRNA expression may be a trait biomarker for SCZ. PMID:27130565

  10. Rho-kinase activation in leukocytes plays a pivotal role in myocardial ischemia/reperfusion injury.

    PubMed

    Kitano, Katsunori; Usui, Soichiro; Ootsuji, Hiroshi; Takashima, Shin-ichiro; Kobayashi, Daisuke; Murai, Hisayoshi; Furusho, Hiroshi; Nomura, Ayano; Kaneko, Shuichi; Takamura, Masayuki

    2014-01-01

    The Rho/Rho-kinase pathway plays an important role in many cardiovascular diseases such as hypertension, atherosclerosis, heart failure, and myocardial infarction. Although previous studies have shown that Rho-kinase inhibitors reduce ischemia/reperfusion (I/R) injury and cytokine production, the role of Rho-kinase in leukocytes during I/R injury is not well understood. Mice were subjected to 30-min ischemia and reperfusion. Rho-kinase activity was significantly greater in leukocytes subjected to myocardial I/R compared to the sham-operated mice. Administration of fasudil, a Rho-kinase inhibitor, significantly reduced the I/R-induced expression of the proinflammatory cytokines interleukin (IL)-6, C-C motif chemoattractant ligand 2 (CCL2), and tumor necrosis factor (TNF)-α, in leukocytes, compared with saline as the vehicle. Furthermore, fasudil decreased I/R-induced myocardial infarction/area at risk (IA) and I/R-induced leukocyte infiltration in the myocardium. Interestingly, IA in fasudil-administered mice with leukocyte depletion was similar to that in fasudil-administered mice. I/R also resulted in remarkable increases in the mRNA expression levels of the proinflammatory cytokines TNF-α, IL-6, and CCL2 in the heart. Inhibition of Rho-kinase activation in leukocytes has an important role in fasudil-induced cardioprotective effects. Hence, inhibition of Rho-kinase may be an additional therapeutic intervention for the treatment of acute coronary syndrome. PMID:24638037

  11. Rho-Kinase Activation in Leukocytes Plays a Pivotal Role in Myocardial Ischemia/Reperfusion Injury

    PubMed Central

    Kitano, Katsunori; Usui, Soichiro; Ootsuji, Hiroshi; Takashima, Shin-ichiro; Kobayashi, Daisuke; Murai, Hisayoshi; Furusho, Hiroshi; Nomura, Ayano; Kaneko, Shuichi; Takamura, Masayuki

    2014-01-01

    The Rho/Rho-kinase pathway plays an important role in many cardiovascular diseases such as hypertension, atherosclerosis, heart failure, and myocardial infarction. Although previous studies have shown that Rho-kinase inhibitors reduce ischemia/reperfusion (I/R) injury and cytokine production, the role of Rho-kinase in leukocytes during I/R injury is not well understood. Mice were subjected to 30-min ischemia and reperfusion. Rho-kinase activity was significantly greater in leukocytes subjected to myocardial I/R compared to the sham-operated mice. Administration of fasudil, a Rho-kinase inhibitor, significantly reduced the I/R-induced expression of the proinflammatory cytokines interleukin (IL)-6, C-C motif chemoattractant ligand 2 (CCL2), and tumor necrosis factor (TNF)-α, in leukocytes, compared with saline as the vehicle. Furthermore, fasudil decreased I/R-induced myocardial infarction/area at risk (IA) and I/R-induced leukocyte infiltration in the myocardium. Interestingly, IA in fasudil-administered mice with leukocyte depletion was similar to that in fasudil-administered mice. I/R also resulted in remarkable increases in the mRNA expression levels of the proinflammatory cytokines TNF-α, IL-6, and CCL2 in the heart. Inhibition of Rho-kinase activation in leukocytes has an important role in fasudil-induced cardioprotective effects. Hence, inhibition of Rho-kinase may be an additional therapeutic intervention for the treatment of acute coronary syndrome. PMID:24638037

  12. Diagnosis of osteomyelitis of the foot in diabetic patients: Value of 111In-leukocyte scintigraphy

    SciTech Connect

    Larcos, G.; Brown, M.L.; Sutton, R.T. )

    1991-09-01

    The noninvasive diagnosis of osteomyelitis of the foot in diabetic patients with currently available radiologic and radionuclide imaging techniques is often difficult. Recently, 111In-labeled leukocyte scintigraphy has been proposed as an attractive alternative. Accordingly, the authors retrospectively reviewed 51 111In-labeled leukocyte scans, 49 technetium-99m bone scans, and 49 plain radiographs obtained in 51 adults with diabetes in whom osteomyelitis of the foot was suspected. The sensitivity and specificity of these techniques were evaluated in all patients, as well as in a subgroup of 11 patients with neuroarthropathy. Results with 111In-labeled leukocyte scans were also examined in subsets of patients with soft-tissue ulcers (n = 35) and those receiving antibiotics during investigation (n = 20). Confirmation or exclusion of osteomyelitis was made surgically in 28 patients and clinically in 23. Fourteen patients had osteomyelitis. Bone scans were most sensitive (93%) but least specific (43%); plain radiographs were most specific (83%) but least sensitive (43%). 111In-labeled leukocyte scans were both sensitive (79%) and specific (78%), and remained useful in patients with neuroarthropathy, soft-tissue ulcers, and antibiotic treatment. Poor spatial resolution contributed to the false-negative and false-positive 111In-labeled leukocyte scans, suggesting that this technique should not be interpreted independent of other tests. 111In-labeled leukocyte scans are a valuable diagnostic tool for the diagnosis of pedal osteomyelitis in diabetic patients.

  13. Highly specific blockade of CCR5 inhibits leukocyte trafficking and reduces mucosal inflammation in murine colitis

    PubMed Central

    Mencarelli, Andrea; Cipriani, Sabrina; Francisci, Daniela; Santucci, Luca; Baldelli, Franco; Distrutti, Eleonora; Fiorucci, Stefano

    2016-01-01

    Targeted disruption of leukocyte trafficking to the gut represents a promising approach for the treatment of inflammatory bowel diseases (IBDs). CCR5, the shared receptor for MIP1α and β and RANTES, is expressed by multiple leukocytes. Here, we aimed to determine the role of CCR5 in mediating leukocyte trafficking in models of colitis, and evaluate the therapeutic potential of maraviroc, an orally active CCR5 antagonist used in the treatment of CCR5-tropic HIV. Acute and chronic colitis were induced by administration of DSS or TNBS to wild-type and CCR5−/− mice or adoptive transfer of splenic naïve CD4+ T-cells from wild type or CCR5−/− mice into RAG-1−/−. CCR5 gene ablation reduced the mucosal recruitment and activation of CCR5-bearing CD4+ and CD11b+ leukocytes, resulting in profound attenuation of signs and symptoms of inflammation in the TNBS and transfer models of colitis. In the DSS/TNBS colitis and in the transfer model, maraviroc attenuated development of intestinal inflammation by selectively reducing the recruitment of CCR5 bearing leukocytes. In summary, CCR5 regulates recruitment of blood leukocytes into the colon indicating that targeting CCR5 may offer therapeutic options in IBDs. PMID:27492684

  14. Leukocyte telomere length predicts overall survival in hepatocellular carcinoma treated with transarterial chemoembolization.

    PubMed

    Liu, Han-Qiang; An, Jia-Ze; Liu, Juan; Yang, Ye-Fa; Zhang, Hong-Xin; Zhao, Bin-Yu; Li, Ji-Bin; Yang, Hu-Shan; Chen, Zhi-Nan; Xing, Jin-Liang

    2012-05-01

    Previous studies have reported that telomere length in peripheral blood leukocytes can predict the clinical outcome of several cancers. However, whether leukocyte telomere length is associated with the prognosis of hepatocellular carcinoma (HCC) remains to be determined. In this study, relative telomere length (RTL) in peripheral blood leukocytes was measured using a real-time PCR-based method for 269 HCC patients treated with transarterial chemoembolization (TACE) from two independent hospitals. The association between RTL and the overall survival (OS) of HCC was analyzed. The immunological function of the HCC patients with different leukocyte RTLs was evaluated. Multivariate analyses indicated that long leukocyte RTL was significantly associated with poor OS of HCC patients, with a hazard ratio of 2.04 (95% confidence interval, 1.46-2.86; P < 0.001). Kaplan-Meier analyses showed a significant difference of median survival time between patients with long and short RTL (log rank P < 0.001). Fluorescence-activated cell sorting analyses showed that the long RTL group had a significantly increased percentage of CD4(+)CD25(+)FOXP3(+) Treg in CD4(+) T cells compared with short RTL group (P = 0.002). In conclusion, our results suggest that leukocyte RTL may serve as an independent prognostic marker for HCC patients treated with TACE. PMID:22318909

  15. Highly specific blockade of CCR5 inhibits leukocyte trafficking and reduces mucosal inflammation in murine colitis.

    PubMed

    Mencarelli, Andrea; Cipriani, Sabrina; Francisci, Daniela; Santucci, Luca; Baldelli, Franco; Distrutti, Eleonora; Fiorucci, Stefano

    2016-01-01

    Targeted disruption of leukocyte trafficking to the gut represents a promising approach for the treatment of inflammatory bowel diseases (IBDs). CCR5, the shared receptor for MIP1α and β and RANTES, is expressed by multiple leukocytes. Here, we aimed to determine the role of CCR5 in mediating leukocyte trafficking in models of colitis, and evaluate the therapeutic potential of maraviroc, an orally active CCR5 antagonist used in the treatment of CCR5-tropic HIV. Acute and chronic colitis were induced by administration of DSS or TNBS to wild-type and CCR5(-/-) mice or adoptive transfer of splenic naïve CD4(+) T-cells from wild type or CCR5(-/-) mice into RAG-1(-/-). CCR5 gene ablation reduced the mucosal recruitment and activation of CCR5-bearing CD4(+) and CD11b(+) leukocytes, resulting in profound attenuation of signs and symptoms of inflammation in the TNBS and transfer models of colitis. In the DSS/TNBS colitis and in the transfer model, maraviroc attenuated development of intestinal inflammation by selectively reducing the recruitment of CCR5 bearing leukocytes. In summary, CCR5 regulates recruitment of blood leukocytes into the colon indicating that targeting CCR5 may offer therapeutic options in IBDs. PMID:27492684

  16. Stress-induced enhancement of leukocyte trafficking into sites of surgery or immune activation

    NASA Astrophysics Data System (ADS)

    Viswanathan, Kavitha; Dhabhar, Firdaus S.

    2005-04-01

    Effective immunoprotection requires rapid recruitment of leukocytes into sites of surgery, wounding, infection, or vaccination. In contrast to immunosuppressive chronic stressors, short-term acute stressors have immunoenhancing effects. Here, we quantify leukocyte infiltration within a surgical sponge to elucidate the kinetics, magnitude, subpopulation, and chemoattractant specificity of an acute stress-induced increase in leukocyte trafficking to a site of immune activation. Mice acutely stressed before sponge implantation showed 200-300% higher neutrophil, macrophage, natural killer cell, and T cell infiltration than did nonstressed animals. We also quantified the effects of acute stress on lymphotactin- (LTN; a predominantly lymphocyte-specific chemokine), and TNF-- (a proinflammatory cytokine) stimulated leukocyte infiltration. An additional stress-induced increase in infiltration was observed for neutrophils, in response to TNF-, macrophages, in response to TNF- and LTN, and natural killer cells and T cells in response to LTN. These results show that acute stress initially increases trafficking of all major leukocyte subpopulations to a site of immune activation. Tissue damage-, antigen-, or pathogen-driven chemoattractants subsequently determine which subpopulations are recruited more vigorously. Such stress-induced increases in leukocyte trafficking may enhance immunoprotection during surgery, vaccination, or infection, but may also exacerbate immunopathology during inflammatory (cardiovascular disease or gingivitis) or autoimmune (psoriasis, arthritis, or multiple sclerosis) diseases. chemokine | psychophysiological stress | surgical sponge | wound healing | lymphotactin

  17. Accelerator considerations of large circular colliders

    NASA Astrophysics Data System (ADS)

    Chao, Alex

    2016-07-01

    As we consider the tremendous physics reaches of the big future circular electron-positron and proton-proton colliders, it might be advisable to keep a close track of what accelerator challenges they face. Good progresses are being made, and yet it is reported here that substantial investments in funding, manpower, as well as a long sustained time to the R&D efforts will be required in preparation to realize these dream colliders.

  18. Polymeric capsule-cushioned leukocyte cell membrane vesicles as a biomimetic delivery platform

    NASA Astrophysics Data System (ADS)

    Gao, Changyong; Wu, Zhiguang; Lin, Zhihua; Lin, Xiankun; He, Qiang

    2016-02-01

    We report a biomimetic delivery of microsized capsule-cushioned leukocyte membrane vesicles (CLMVs) through the conversion of freshly reassembled leukocyte membrane vesicles (LMVs), including membrane lipids and membrane-bound proteins onto the surface of layer-by-layer assembled polymeric multilayer microcapsules. The leukocyte membrane coating was verified by using electron microscopy, a quartz crystal microbalance, dynamic light scattering, and confocal laser scanning microscopy. The resulting CLMVs have the ability to effectively evade clearance by the immune system and thus prolong the circulation time in mice. Moreover, we also show that the right-side-out leukocyte membrane coating can distinctly improve the accumulation of capsules in tumor sites through the molecular recognition of membrane-bound proteins of CLMVs with those of tumor cells in vitro and in vivo. The natural cell membrane camouflaged polymeric multilayer capsules with the immunosuppressive and tumor-recognition functionalities of natural leukocytes provide a new biomimetic delivery platform for disease therapy.We report a biomimetic delivery of microsized capsule-cushioned leukocyte membrane vesicles (CLMVs) through the conversion of freshly reassembled leukocyte membrane vesicles (LMVs), including membrane lipids and membrane-bound proteins onto the surface of layer-by-layer assembled polymeric multilayer microcapsules. The leukocyte membrane coating was verified by using electron microscopy, a quartz crystal microbalance, dynamic light scattering, and confocal laser scanning microscopy. The resulting CLMVs have the ability to effectively evade clearance by the immune system and thus prolong the circulation time in mice. Moreover, we also show that the right-side-out leukocyte membrane coating can distinctly improve the accumulation of capsules in tumor sites through the molecular recognition of membrane-bound proteins of CLMVs with those of tumor cells in vitro and in vivo. The natural

  19. Loss function used in optimization of array of coupled tracking radioelectronic systems

    NASA Astrophysics Data System (ADS)

    Vagapov, V. B.

    1984-05-01

    A loss function is defined as a criterion for optimization of coupled multidimensional tracking systems, in preference to the two conventional complementary loss functions relative to the maximum tracking accuracy and the permissible range of tracking error respectively. The penalty of error is calculated accordingly by solution of the corresponding equation of motion for the tracking system, specifically a second-order (velocity-acceleration) tracking system in which the discriminator output signal is an additive mixture of tracking error and interference. First, such a one dimensional tracking system is considered and next, a two dimensional system consisting of two such one dimensional ones coupled through the error of their identical respective tracking loops. The mathematical expectation of this loss function was calculated as a function of the slope of the discriminator characteristic, the curves for n = 2,4,8 were normalized to minimum values of the corresponding loss function.

  20. Social regulation of gene expression in human leukocytes

    PubMed Central

    Cole, Steve W; Hawkley, Louise C; Arevalo, Jesusa M; Sung, Caroline Y; Rose, Robert M; Cacioppo, John T

    2007-01-01

    Background Social environmental influences on human health are well established in the epidemiology literature, but their functional genomic mechanisms are unclear. The present study analyzed genome-wide transcriptional activity in people who chronically experienced high versus low levels of subjective social isolation (loneliness) to assess alterations in the activity of transcription control pathways that might contribute to increased adverse health outcomes in social isolates. Results DNA microarray analysis identified 209 genes that were differentially expressed in circulating leukocytes from 14 high- versus low-lonely individuals, including up-regulation of genes involved in immune activation, transcription control, and cell proliferation, and down-regulation of genes supporting mature B lymphocyte function and type I interferon response. Promoter-based bioinformatic analyses showed under-expression of genes bearing anti-inflammatory glucocorticoid response elements (GREs; p = 0.032) and over-expression of genes bearing response elements for pro-inflammatory NF-κB/Rel transcription factors (p = 0.011). This reciprocal shift in pro- and anti-inflammatory signaling was not attributable to differences in circulating cortisol levels, or to other demographic, psychological, or medical characteristics. Additional transcription control pathways showing differential activity in bioinformatic analyses included the CREB/ATF, JAK/STAT, IRF1, C/EBP, Oct, and GATA pathways. Conclusion These data provide the first indication that human genome-wide transcriptional activity is altered in association with a social epidemiological risk factor. Impaired transcription of glucocorticoid response genes and increased activity of pro-inflammatory transcription control pathways provide a functional genomic explanation for elevated risk of inflammatory disease in individuals who experience chronically high levels of subjective social isolation. PMID:17854483

  1. Thyrotropin Receptor Epitope and Human Leukocyte Antigen in Graves' Disease.

    PubMed

    Inaba, Hidefumi; De Groot, Leslie J; Akamizu, Takashi

    2016-01-01

    Graves' disease (GD) is an organ-specific autoimmune disease, and thyrotropin (TSH) receptor (TSHR) is a major autoantigen in this condition. Since the extracellular domain of human TSHR (TSHR-ECD) is shed into the circulation, TSHR-ECD is a preferentially immunogenic portion of TSHR. Both genetic factors and environmental factors contribute to development of GD. Inheritance of human leukocyte antigen (HLA) genes, especially HLA-DR3, is associated with GD. TSHR-ECD protein is endocytosed into antigen-presenting cells (APCs), and processed to TSHR-ECD peptides. These peptide epitopes bind to HLA-class II molecules, and subsequently the complex of HLA-class II and TSHR-ECD epitope is presented to CD4+ T cells. The activated CD4+ T cells secrete cytokines/chemokines that stimulate B-cells to produce TSAb, and in turn hyperthyroidism occurs. Numerous studies have been done to identify T- and B-cell epitopes in TSHR-ECD, including (1) in silico, (2) in vitro, (3) in vivo, and (4) clinical experiments. Murine models of GD and HLA-transgenic mice have played a pivotal role in elucidating the immunological mechanisms. To date, linear or conformational epitopes of TSHR-ECD, as well as the molecular structure of the epitope-binding groove in HLA-DR, were reported to be related to the pathogenesis in GD. Dysfunction of central tolerance in the thymus, or in peripheral tolerance, such as regulatory T cells, could allow development of GD. Novel treatments using TSHR antagonists or mutated TSHR peptides have been reported to be effective. We review and update the role of immunogenic TSHR epitopes and HLA in GD, and offer perspectives on TSHR epitope specific treatments. PMID:27602020

  2. Leukocyte labeling with isonitrile complexes of Tc-99m

    SciTech Connect

    Van den Abbeele, A.D.; Solorzano, C.; Jones, A.G.; Beardsley, D.S.; Treves, S.; Davison, A.

    1985-05-01

    Leukocyte labelling with Tc-99m may result in a useful method for the detection and localization of active inflammatory processes in patients, particularly in the pediatric population. Previous studies qin this laboratory have shown that hexakis(alkylisonitrile)technetium(I) complexes readily label V79 lung fibroblasts in vitro, and this work is now being extended to isolated human white blood cells (WBC). Two lipophilic water-soluble technetium cations, the t-butyl (Tc-99m(TBI)) and cyclohexyl (Tc-99m(CHI)) analogs, were prepared essentially ligand-free at no-carrier-added levels in aqueous media and introduced in 10% propylene glycol/90% normal saline solution to WBC at room temperature. The cells were isolated from whole blood via sedimentation, centrifugation, and hypotonic hemolysis of the red blood cells. The labeling yield was studied as a function of incubation time (10-45 min), amount of activity (0.35-8.0 mCi), and total WBC (2.5 x 10/sup 7/-1.3 x 10/sup 8/). After 10 min incubation using 10/sup 8/ cells, the initial uptake of Tc-99m(TBI) was 40%, of which 50% remained bound after one saline wash. By contrast, the labeling efficiency with Tc-99m(CHI) was 85%, with 90% of the label still bound after washing. The labeling yield was unrelated to activity levels of incubation time, but was proportional to the number of WBC present. The entire process could be complemented in approximately one hour. The labeling yields with Tc-99m-(CHI) are comparable to those now obtained with the clinically available In-111 oxine.

  3. Imputing amino acid polymorphisms in human leukocyte antigens.

    PubMed

    Jia, Xiaoming; Han, Buhm; Onengut-Gumuscu, Suna; Chen, Wei-Min; Concannon, Patrick J; Rich, Stephen S; Raychaudhuri, Soumya; de Bakker, Paul I W

    2013-01-01

    DNA sequence variation within human leukocyte antigen (HLA) genes mediate susceptibility to a wide range of human diseases. The complex genetic structure of the major histocompatibility complex (MHC) makes it difficult, however, to collect genotyping data in large cohorts. Long-range linkage disequilibrium between HLA loci and SNP markers across the major histocompatibility complex (MHC) region offers an alternative approach through imputation to interrogate HLA variation in existing GWAS data sets. Here we describe a computational strategy, SNP2HLA, to impute classical alleles and amino acid polymorphisms at class I (HLA-A, -B, -C) and class II (-DPA1, -DPB1, -DQA1, -DQB1, and -DRB1) loci. To characterize performance of SNP2HLA, we constructed two European ancestry reference panels, one based on data collected in HapMap-CEPH pedigrees (90 individuals) and another based on data collected by the Type 1 Diabetes Genetics Consortium (T1DGC, 5,225 individuals). We imputed HLA alleles in an independent data set from the British 1958 Birth Cohort (N = 918) with gold standard four-digit HLA types and SNPs genotyped using the Affymetrix GeneChip 500 K and Illumina Immunochip microarrays. We demonstrate that the sample size of the reference panel, rather than SNP density of the genotyping platform, is critical to achieve high imputation accuracy. Using the larger T1DGC reference panel, the average accuracy at four-digit resolution is 94.7% using the low-density Affymetrix GeneChip 500 K, and 96.7% using the high-density Illumina Immunochip. For amino acid polymorphisms within HLA genes, we achieve 98.6% and 99.3% accuracy using the Affymetrix GeneChip 500 K and Illumina Immunochip, respectively. Finally, we demonstrate how imputation and association testing at amino acid resolution can facilitate fine-mapping of primary MHC association signals, giving a specific example from type 1 diabetes. PMID:23762245

  4. Characterization of decidual leukocyte populations in cynomolgus and vervet monkeys

    PubMed Central

    Dambaeva, Svetlana V.; Breburda, Edith E.; Durning, Maureen; Garthwaite, Mark A.; Golos, Thaddeus G.

    2011-01-01

    The objective of this study was the phenotypic and functional evaluation of decidual immune cells in the cynomolgus and vervet monkeys. Early pregnancy (day 36-42) deciduas were obtained by fetectomy for histological evaluation and decidual mononuclear leukocyte (MNL) isolation. While peripheral NK (pNK) cells in these species do not express CD56, CD56+ NK cells were abundant in decidual samples. The majority of decidual NK (dNK) cells (>80%) had high light-scatter characteristics and were CD56brightCD16+ cells with no or very low levels of natural cytotoxicity receptors (NKp46, NKp30) and NKG2A, while a minor population were small CD56dimCD16-lymphocytes also expressing less NKp46, NKp30 and NKG2A than pNK cells. All dNK cells were found to be perforin+; however, their cytotoxic potential was low and cynomolgus dNK cells showed strongly reduced cytotoxicity against target cells compared with pNK cells. Macrophages and T cells together comprised approximately 25-30% of decidual MNL. Decidual T cells contained a higher proportion of the minor T cell subtypes (γδT cells, CD56+ T cells) compared with peripheral blood. A subset of DC-SIGN+ macrophages, with a distribution adjacent to areas of placental attachment in contrast to the widespread setting of general CD68+ cells, was identified in both species. Together, these results demonstrate that the maternal-fetal interface in both cynomolgus and vervet monkeys is very rich in immune cells that have similar phenotypes to those seen in humans, indicating that both species are excellent models to study the contributions of distinct immune cell populations to pregnancy support. PMID:19398130

  5. Thyrotropin Receptor Epitope and Human Leukocyte Antigen in Graves’ Disease

    PubMed Central

    Inaba, Hidefumi; De Groot, Leslie J.; Akamizu, Takashi

    2016-01-01

    Graves’ disease (GD) is an organ-specific autoimmune disease, and thyrotropin (TSH) receptor (TSHR) is a major autoantigen in this condition. Since the extracellular domain of human TSHR (TSHR-ECD) is shed into the circulation, TSHR-ECD is a preferentially immunogenic portion of TSHR. Both genetic factors and environmental factors contribute to development of GD. Inheritance of human leukocyte antigen (HLA) genes, especially HLA-DR3, is associated with GD. TSHR-ECD protein is endocytosed into antigen-presenting cells (APCs), and processed to TSHR-ECD peptides. These peptide epitopes bind to HLA-class II molecules, and subsequently the complex of HLA-class II and TSHR-ECD epitope is presented to CD4+ T cells. The activated CD4+ T cells secrete cytokines/chemokines that stimulate B-cells to produce TSAb, and in turn hyperthyroidism occurs. Numerous studies have been done to identify T- and B-cell epitopes in TSHR-ECD, including (1) in silico, (2) in vitro, (3) in vivo, and (4) clinical experiments. Murine models of GD and HLA-transgenic mice have played a pivotal role in elucidating the immunological mechanisms. To date, linear or conformational epitopes of TSHR-ECD, as well as the molecular structure of the epitope-binding groove in HLA-DR, were reported to be related to the pathogenesis in GD. Dysfunction of central tolerance in the thymus, or in peripheral tolerance, such as regulatory T cells, could allow development of GD. Novel treatments using TSHR antagonists or mutated TSHR peptides have been reported to be effective. We review and update the role of immunogenic TSHR epitopes and HLA in GD, and offer perspectives on TSHR epitope specific treatments. PMID:27602020

  6. Leukocyte Extravasation: An immunoregulatory role for α-L Fucosidase?

    PubMed Central

    Ali, Simi; Jenkins, Yvonne; Kirkley, Maureen; Dagkalis, Athanasios; Manivannan, Ayyakkannu; Crane, Isabel Joan; Kirby, John A

    2009-01-01

    Fucosylated oligosaccharides and glycoconjugates have been implicated in several biological events, including the cell-cell adhesion processes which mediate inflammation. Alpha-L-fucosidase (ALF) is an exoglycosidase which is involved in the hydrolytic degradation of α-L-fucose from glycoconjugates. In this study we investigated the potential role of ALF in regulation of leukocyte migration. Measurement of trans-endothelial migration in response to CCL5 demonstrated that pre-treatment of monocytic cells with ALF reduced migration (p=0.0004) to a greater extent than treatment of the endothelial monolayer (p=0.0374). Treatment with ALF significantly reduced the adhesion of monocytic cells to immobilized P-selectin.Fc. A murine model of experimental autoimmune uveitis was then used to show that treatment of splenic cells with ALF produced an 8.6-fold decrease in rolling and a 3.2-fold decrease in cell migration across the retinal vasculature. Further in vitro studies demonstrated that treatment of monocytes with the chemokines CCL3 or CCL5 increased the level of mRNA encoding ALF; this was accompanied by the detection of significant increases in both the 51kDa and 56kDa components of ALF by Western blotting. Treatment of monocytic cells with ALF for 2h significantly reduced the cell-surface expression of CD31, with a further decrease in expression observed after 5h (p=0.002). Thus, CD31 and fucosylated ligands of P-selectin seem to be the candidates through which ALF mediates its effect in vitro. These data identify a previously unrecognized immunoregulatory role for ALF in late stages of inflammation. PMID:18684930

  7. Software for large scale tracking studies

    SciTech Connect

    Niederer, J.

    1984-05-01

    Over the past few years, Brookhaven accelerator physicists have been adapting particle tracking programs in planning local storage rings, and lately for SSC reference designs. In addition, the Laboratory is actively considering upgrades to its AGS capabilities aimed at higher proton intensity, polarized proton beams, and heavy ion acceleration. Further activity concerns heavy ion transfer, a proposed booster, and most recently design studies for a heavy ion collider to join to this complex. Circumstances have thus encouraged a search for common features among design and modeling programs and their data, and the corresponding controls efforts among present and tentative machines. Using a version of PATRICIA with nonlinear forces as a vehicle, we have experimented with formal ways to describe accelerator lattice problems to computers as well as to speed up the calculations for large storage ring models. Code treated by straightforward reorganization has served for SSC explorations. The representation work has led to a relational data base centered program, LILA, which has desirable properties for dealing with the many thousands of rapidly changing variables in tracking and other model programs. 13 references.

  8. Maximum power tracking

    SciTech Connect

    O'Sullivan, G.

    1983-03-01

    By definition, a maximum power tracking device causes the photovoltaic array to operate on the locus of maximum power points within a specified accuracy. There are limitations to the application of maximum power tracking. A prerequisite is that the load be capable of absorbing all of the power availble at all times. Battery chargers, electrical heaters, water pumps, and most significantly, returning power to the utility grid, are prime examples of applications that are adaptable to maximum power tracking. Maximum power tracking is available to either dc or ac loads. An inverter equipped with a means of changing input voltage by controlling its input impedance can deliver maximum power to ac loads. The inverter can be fixed or variable frequency and fixed or variable voltage, but must be compatible with the ac load. The discussion includes applications, techniques, and cost factors.

  9. Enhanced optical tracking

    NASA Astrophysics Data System (ADS)

    McSheery, Tracy

    2008-04-01

    Enhanced tracking is accomplished by increasing the resolution, frame rate and processing capabilities in tracking dynamic regions of interest for vision applications. In many proven algorithms, the ability to distinguish an object and track it is dependent on the system performance in more than one attribute. We have conducted studies on proven techniques such as Active Appearance Models, Principle Component Analysis and Eigen tracking. All perform better as the camera resolution increases, and camera frame rate increases. Additional opportunities have been observed by combining these techniques, taking advantage of Multicore CPUs, and GPU graphic card processing. Results from an 8 Megapixel commercial sensor combined with a Field Programmable Gate array are presented, and algorithm performance compared with down scaled images of the same scenes, and simulated typical 30 hertz frame rates verses the 120 hertz to 300 hertz typical of this smart camera.

  10. Effects of acute systemic administration of TiO2, ZnO, SiO2, and Ag nanoparticles on hemodynamics, hemostasis and leukocyte recruitment.

    PubMed

    Haberl, Nadine; Hirn, Stephanie; Holzer, Martin; Zuchtriegel, Gabriele; Rehberg, Markus; Krombach, Fritz

    2015-01-01

    It has been suggested that engineered nanomaterials (ENM), once arrived in the circulation, may affect the cardiovascular system. The aim of this in vivo study was to screen major cardiovascular effects of acute systemic administration of a panel of five nanomaterials, TiO2 anatase (NM-101), TiO2 rutile (NM-104), ZnO (NM-110), SiO2 (NM-200) and Ag (NM-300). Mice were anesthetized and the ENM were injected at a dose of 1 mg/kg via a catheter placed in the left femoral artery. Hemodynamic parameters were determined by invasive measurement of blood pressure and non-invasive measurement of heart rate. Ten minutes after injection of the ENM, the formation of light/dye-induced thrombi was assessed in the cremasteric microcirculation by intravital microscopy. In addition, the numbers of rolling, firmly adherent and transmigrated leukocytes were recorded in postcapillary cremasteric venules over a time period of 120 min after injection of ENM by intravital microscopy. The systemic administration of a single dose of the ENM tested did not dramatically alter hemodynamic parameters or affect early steps of leukocyte recruitment. However, the presence of circulating TiO2 anatase, but not of TiO2 rutile, SiO2, ZnO or Ag nanoparticles, significantly accelerated thrombus formation in the murine microcirculation. Moreover, TiO2 anatase but not TiO2 rutile nanoparticles increased murine platelet aggregation in vitro. Taken together, only one of the five systemically administered ENM, TiO2 anatase, affected hemostasis, whereas none of the ENM tested in this screening study dramatically modulated hemodynamic parameters or early steps of leukocyte recruitment. PMID:25670207

  11. Nanowire array chips for molecular typing of rare trafficking leukocytes with application to neurodegenerative pathology

    NASA Astrophysics Data System (ADS)

    Kwak, Minsuk; Kim, Dong-Joo; Lee, Mi-Ri; Wu, Yu; Han, Lin; Lee, Sang-Kwon; Fan, Rong

    2014-05-01

    Despite the presence of the blood-brain barrier (BBB) that restricts the entry of immune cells and mediators into the central nervous system (CNS), a small number of peripheral leukocytes can traverse the BBB and infiltrate into the CNS. The cerebrospinal fluid (CSF) is one of the major routes through which trafficking leukocytes migrate into the CNS. Therefore, the number of leukocytes and their phenotypic compositions in the CSF may represent important sources to investigate immune-to-brain interactions or diagnose and monitor neurodegenerative diseases. Due to the paucity of trafficking leucocytes in the CSF, a technology capable of efficient isolation, enumeration, and molecular typing of these cells in the clinical settings has not been achieved. In this study, we report on a biofunctionalized silicon nanowire array chip for highly efficient capture and multiplexed phenotyping of rare trafficking leukocytes in small quantities (50 microliters) of clinical CSF specimens collected from neurodegenerative disease patients. The antibody coated 3D nanostructured materials exhibited vastly improved rare cell capture efficiency due to high-affinity binding and enhanced cell-substrate interactions. Moreover, our platform creates multiple cell capture interfaces, each of which can selectively isolate specific leukocyte phenotypes. A comparison with the traditional immunophenotyping using flow cytometry demonstrated that our novel silicon nanowire-based rare cell analysis platform can perform rapid detection and simultaneous molecular characterization of heterogeneous immune cells. Multiplexed molecular typing of rare leukocytes in CSF samples collected from Alzheimer's disease patients revealed the elevation of white blood cell counts and significant alterations in the distribution of major leukocyte phenotypes. Our technology represents a practical tool for potentially diagnosing and monitoring the pathogenesis of neurodegenerative diseases by allowing an effective

  12. Nanowire array chips for molecular typing of rare trafficking leukocytes with application to neurodegenerative pathology

    NASA Astrophysics Data System (ADS)

    Kwak, Minsuk; Kim, Dong-Joo; Lee, Mi-Ri; Wu, Yu; Han, Lin; Lee, Sang-Kwon; Fan, Rong

    2014-05-01

    Despite the presence of the blood-brain barrier (BBB) that restricts the entry of immune cells and mediators into the central nervous system (CNS), a small number of peripheral leukocytes can traverse the BBB and infiltrate into the CNS. The cerebrospinal fluid (CSF) is one of the major routes through which trafficking leukocytes migrate into the CNS. Therefore, the number of leukocytes and their phenotypic compositions in the CSF may represent important sources to investigate immune-to-brain interactions or diagnose and monitor neurodegenerative diseases. Due to the paucity of trafficking leucocytes in the CSF, a technology capable of efficient isolation, enumeration, and molecular typing of these cells in the clinical settings has not been achieved. In this study, we report on a biofunctionalized silicon nanowire array chip for highly efficient capture and multiplexed phenotyping of rare trafficking leukocytes in small quantities (50 microliters) of clinical CSF specimens collected from neurodegenerative disease patients. The antibody coated 3D nanostructured materials exhibited vastly improved rare cell capture efficiency due to high-affinity binding and enhanced cell-substrate interactions. Moreover, our platform creates multiple cell capture interfaces, each of which can selectively isolate specific leukocyte phenotypes. A comparison with the traditional immunophenotyping using flow cytometry demonstrated that our novel silicon nanowire-based rare cell analysis platform can perform rapid detection and simultaneous molecular characterization of heterogeneous immune cells. Multiplexed molecular typing of rare leukocytes in CSF samples collected from Alzheimer's disease patients revealed the elevation of white blood cell counts and significant alterations in the distribution of major leukocyte phenotypes. Our technology represents a practical tool for potentially diagnosing and monitoring the pathogenesis of neurodegenerative diseases by allowing an effective

  13. Advanced Doppler tracking experiments

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.

    1989-01-01

    The Doppler tracking method is currently the only technique available for broadband gravitational wave searches in the approx. 10(exp -4) to 10(exp -1) Hz low frequency band. A brief review is given of the Doppler method, a discussion of the main noise sources, and a review of experience with current spacecraft and the prospects for sensitivity improvements in an advanced Doppler tracking experiment.

  14. Physical Models for Particle Tracking Simulations in the RF Gap

    SciTech Connect

    Shishlo, Andrei P.; Holmes, Jeffrey A.

    2015-06-01

    This document describes the algorithms that are used in the PyORBIT code to track the particles accelerated in the Radio-Frequency cavities. It gives the mathematical description of the algorithms and the assumptions made in each case. The derived formulas have been implemented in the PyORBIT code. The necessary data for each algorithm are described in detail.

  15. Continuous Quantitative Measurements on a Linear Air Track

    ERIC Educational Resources Information Center

    Vogel, Eric

    1973-01-01

    Describes the construction and operational procedures of a spark-timing apparatus which is designed to record the back and forth motion of one or two carts on linear air tracks. Applications to measurements of velocity, acceleration, simple harmonic motion, and collision problems are illustrated. (CC)

  16. Fast SIMDized Kalman filter based track fit

    NASA Astrophysics Data System (ADS)

    Gorbunov, S.; Kebschull, U.; Kisel, I.; Lindenstruth, V.; Müller, W. F. J.

    2008-03-01

    Modern high energy physics experiments have to process terabytes of input data produced in particle collisions. The core of many data reconstruction algorithms in high energy physics is the Kalman filter. Therefore, the speed of Kalman filter based algorithms is of crucial importance in on-line data processing. This is especially true for the combinatorial track finding stage where the Kalman filter based track fit is used very intensively. Therefore, developing fast reconstruction algorithms, which use maximum available power of processors, is important, in particular for the initial selection of events which carry signals of interesting physics. One of such powerful feature supported by almost all up-to-date PC processors is a SIMD instruction set, which allows packing several data items in one register and to operate on all of them, thus achieving more operations per clock cycle. The novel Cell processor extends the parallelization further by combining a general-purpose PowerPC processor core with eight streamlined coprocessing elements which greatly accelerate vector processing applications. In the investigation described here, after a significant memory optimization and a comprehensive numerical analysis, the Kalman filter based track fitting algorithm of the CBM experiment has been vectorized using inline operator overloading. Thus the algorithm continues to be flexible with respect to any CPU family used for data reconstruction. Because of all these changes the SIMDized Kalman filter based track fitting algorithm takes 1 μs per track that is 10000 times faster than the initial version. Porting the algorithm to a Cell Blade computer gives another factor of 10 of the speedup. Finally, we compare performance of the tracking algorithm running on three different CPU architectures: Intel Xeon, AMD Opteron and Cell Broadband Engine.

  17. MATERIAL TRACKING USING LANMAS

    SciTech Connect

    Armstrong, F.

    2010-06-07

    LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

  18. Technetium-99m HM-PAO-labeled leukocytes in detection of inflammatory lesions: Comparison with gallium-67 citrate

    SciTech Connect

    Vorne, M.; Soini, I.; Lantto, T.; Paakkinen, S. )

    1989-08-01

    Forty-three patients with suspected benign, inflammatory, or infectious diseases were imaged with ({sup 99m}Tc)HM-PAO-labeled leukocytes and ({sup 67}Ga)citrate. Technetium-99m leukocytes showed 22 true-positive, no false-positive, 19 true-negative, and two false-negative findings and ({sup 67}Ga)citrate 23, 7, 12 and 1, respectively. The sensitivity, specificity, and accuracy values with {sup 99m}Tc leukocytes were 92%, 100%, and 95%, and with ({sup 67}Ga)citrate 96%, 63%, and 81%. Technetium-99m leukocyte scintigraphy has a promising future in comparison with ({sup 67}Ga)citrate because of the ready availability of ({sup 99m}Tc)HM-PAO, the good image quality, more rapid results (within few hours), and the lower radiation exposure to the patient with {sup 99m}Tc leukocytes. The usefulness of {sup 99m}Tc leukocytes in chronic osteomyelitis needs further evaluation.

  19. Altered expression of adhesion molecules on peripheral blood leukocytes in feline infectious peritonitis.

    PubMed

    Olyslaegers, Dominique A J; Dedeurwaerder, Annelike; Desmarets, Lowiese M B; Vermeulen, Ben L; Dewerchin, Hannah L; Nauwynck, Hans J

    2013-10-25

    Feline infectious peritonitis (FIP) is a fatal, coronavirus-induced systemic disease in domestic and wild felids. The pathology associated with FIP (multifocal granulomatous vasculitis) is considered to be elicited by exaggerated activation and subsequent extravasation of leukocytes. As changes in the expression of adhesion molecules on circulating leukocytes precede their margination and emigration, we reasoned that the expression of leukocyte adhesion molecules may be altered in FIP. In present study, the expression of principal adhesion molecules involved in leukocyte transmigration (CD15s, CD11a, CD11b, CD18, CD49d, and CD54) on peripheral blood leukocytes from cats with naturally occurring FIP (n=15) and controls (n=12) was quantified by flow cytometry using a formaldehyde-based rapid leukocyte preparation technique. T- and B-lymphocytes from FIP patients exhibit higher expression of both subunits (CD11a and CD18) composing the β2 integrin lymphocyte function-associated antigen (LFA)-1. In addition, the expression of the α4 subunit (CD49d) of the β1 integrin very late antigen (VLA)-4 was elevated on B-lymphocytes from FIP patients. The expression of CD11b and CD18, that combine to form the β2 integrin macrophage-1 antigen (Mac-1), was elevated on monocytes, whereas the density of CD49d was reduced on this population in FIP. Granulocytes of FIP cats displayed an increased expression of the α chain of Mac-1 (CD11b). These observations suggest that leukocytes from FIP patients show signs of systemic activation causing them to extravasate into surrounding tissues and ultimately contribute to pyogranuloma formation seen in FIP. PMID:23910523

  20. Chemokine Ligand 20: A Signal for Leukocyte Recruitment During Human Ovulation?

    PubMed

    Al-Alem, Linah; Puttabyatappa, Muraly; Rosewell, Kathy; Brännström, Mats; Akin, James; Boldt, Jeffrey; Muse, Ken; Curry, Thomas E

    2015-09-01

    Ovulation is one of the cornerstones of female fertility. Disruption of the ovulatory process results in infertility, which affects approximately 10% of couples. Using a unique model in which the dominant follicle is collected across the periovulatory period in women, we have identified a leukocyte chemoattractant, chemokine ligand 20 (CCL20), in the human ovary. CCL20 mRNA is massively induced after an in vivo human chorionic gonadotropin (hCG) stimulus in granulosa (>10 000-fold) and theca (>4000-fold) cells collected during the early ovulatory (12-18 h) and late ovulatory (18-34 h) periods after hCG administration. Because the LH surge sets in motion an inflammatory reaction characterized by an influx of leukocytes and CCL20 is known to recruit leukocytes in other systems, the composition of ovarian leukocytes (CD45+) containing the CCL20 receptor CCR6 was determined immediately prior to ovulation. CD45+/CCR6+ cells were primarily natural killer cells (41%) along with B cells (12%), T cells (11%), neutrophils (10%), and monocytes (9%). Importantly, exogenous CCL20 stimulated ovarian leukocyte migration 59% within 90 minutes. Due to the difficulties in obtaining human follicles, an in vitro model was developed using granulosa-lutein cells to explore CCL20 regulation. CCL20 expression increased 40-fold within 6 hours after hCG, was regulated partially by the epithelial growth factor pathway, and was positively correlated with progesterone production. These results demonstrate that hCG dramatically increases CCL20 expression in the human ovary, that ovarian leukocytes contain the CCL20 receptor, and that CCL20 stimulates leukocyte migration. Our findings raise the prospect that CCL20 may aid in the final ovulatory events and contribute to fertility in women. PMID:26125463

  1. Isolation of Leukocytes from the Murine Tissues at the Maternal-Fetal Interface.

    PubMed

    Arenas-Hernandez, Marcia; Sanchez-Rodriguez, Elly N; Mial, Tara N; Robertson, Sarah A; Gomez-Lopez, Nardhy

    2015-01-01

    Immune tolerance in pregnancy requires that the immune system of the mother undergoes distinctive changes in order to accept and nurture the developing fetus. This tolerance is initiated during coitus, established during fecundation and implantation, and maintained throughout pregnancy. Active cellular and molecular mediators of maternal-fetal tolerance are enriched at the site of contact between fetal and maternal tissues, known as the maternal-fetal interface, which includes the placenta and the uterine and decidual tissues. This interface is comprised of stromal cells and infiltrating leukocytes, and their abundance and phenotypic characteristics change over the course of pregnancy. Infiltrating leukocytes at the maternal-fetal interface include neutrophils, macrophages, dendritic cells, mast cells, T cells, B cells, NK cells, and NKT cells that together create the local micro-environment that sustains pregnancy. An imbalance among these cells or any inappropriate alteration in their phenotypes is considered a mechanism of disease in pregnancy. Therefore, the study of leukocytes that infiltrate the maternal-fetal interface is essential in order to elucidate the immune mechanisms that lead to pregnancy-related complications. Described herein is a protocol that uses a combination of gentle mechanical dissociation followed by a robust enzymatic disaggregation with a proteolytic and collagenolytic enzymatic cocktail to isolate the infiltrating leukocytes from the murine tissues at the maternal-fetal interface. This protocol allows for the isolation of high numbers of viable leukocytes (>70%) with sufficiently conserved antigenic and functional properties. Isolated leukocytes can then be analyzed by several techniques, including immunophenotyping, cell sorting, imaging, immunoblotting, mRNA expression, cell culture, and in vitro functional assays such as mixed leukocyte reactions, proliferation, or cytotoxicity assays. PMID:26067389

  2. Leukocyte Cell-Derived Chemotaxin 2-Associated Amyloidosis: A Recently Recognized Disease with Distinct Clinicopathologic Characteristics.

    PubMed

    Nasr, Samih H; Dogan, Ahmet; Larsen, Christopher P

    2015-11-01

    Amyloidosis derived from leukocyte cell-derived chemotaxin 2 is a recently recognized form of amyloidosis, and it has already been established as a frequent form of systemic amyloidosis in the United States, with predominant involvement of kidney and liver. The disease has a strong ethnic bias, affecting mainly Hispanics (particularly Mexicans). Additional ethnic groups prone to develop amyloidosis derived from leukocyte cell-derived chemotaxin 2 include Punjabis, First Nations people in British Columbia, and Native Americans. Most patients are elderly who present with chronic renal insufficiency and bland urinary sediment. Proteinuria is variable, being absent altogether in about one third of patients. Liver involvement is frequently an incidental finding. Amyloidosis derived from leukocyte cell-derived chemotaxin 2 deposits shows a characteristic distribution: in the kidney, there is consistent involvement of cortical interstitium, whereas in the liver, there is a preferential involvement of periportal and pericentral vein regions. Concurrent renal disease is frequent, with diabetic nephropathy and IgA nephropathy being the most common. Patient survival is excellent, likely because of the rarity of cardiac involvement, whereas renal survival is guarded, with a median renal survival of 62 months in those without concurrent renal disease. There is currently no efficacious therapy for amyloidosis derived from leukocyte cell-derived chemotaxin 2 amyloidosis. Renal transplantation seems to be a reasonable treatment for patients with advanced renal failure, although the disease may recur in the allograft. The pathogenesis of amyloidosis derived from leukocyte cell-derived chemotaxin 2 amyloidosis has not yet been elucidated. It could be a result of leukocyte cell-derived chemotaxin 2 overexpression by hepatocytes either constitutively (controlled by yet-uncharacterized genetic defects) or secondary to hepatocellular damage. It is critical not to misdiagnose amyloidosis

  3. The evaluation of leukocytes in response to the in vitro testing of ventricular assist devices.

    PubMed

    Chan, Chris H H; Hilton, Andrew; Foster, Graham; Hawkins, Karl M; Badiei, Nafiseh; Thornton, Catherine A

    2013-09-01

    Infection is a clinically relevant adverse event in patients with ventricular assist device (VAD) support. The risk of infection could be linked to a reduced immune response resulting from damage to leukocytes during VAD support. The purpose of this study was to develop an understanding of leukocyte responses during the in vitro testing of VADs by analyzing the changes to their morphology and biochemistry. The VentrAssist implantable rotary blood pump (IRBP) and RotaFlow centrifugal pump (CP) were tested in vitro under constant hemodynamic conditions. Automated hematology analysis of samples collected regularly over 25-h tests was undertaken. A new flow cytometric assay was employed to measure biochemical alteration, necrosis (7-AAD) and morphological alteration (CD45 expression) of the circulating leukocytes during the pumping process. The results of hematology analysis show the total leukocyte number and subset counts decreased over the period of in vitro tests dependent on different blood pumps. The percentage of leukocytes damaged during 6-h tests was 40.8 ± 5.7% for the VentrAssist IRBP, 17.6 ± 5.4% for the RotaFlow CP, and 2.7 ± 1.8% for the static control (all n=5). Flow cytometric monitoring of CD45 expression and forward/side scatter characteristics revealed leukocytes that were fragmented into smaller pieces (microparticles). Scanning electron microscopy and imaging flow cytometry were used to confirm this. Device developers could use these robust cellular assays to gain a better understanding of leukocyte-specific VAD performance. PMID:23981196

  4. Indium 111-labeled leukocyte scanning for detection of prosthetic vascular graft infection

    SciTech Connect

    Lawrence, P.F.; Dries, D.J.; Alazraki, N.; Albo, D. Jr.

    1985-01-01

    Recent animal and human studies have suggested that positive indium 111-labeled leukocyte scans may help establish the diagnosis of vascular graft infection; however, there is little information available about the predictive value of both positive and negative leukocyte scans in larger groups of patients. In this study 31 indium 111 leukocyte scans were performed prior to definitive treatment in 21 patients with suspected vascular graft infections. Patients with more than one leukocyte scan performed had either anatomically distinct sites of infection or rescanning of a potentially infected site after definitive treatment. Scans were performed according to the method of Baker et al., attaching 500 muCi of indium 111 to leukocytes with imaging 24 hours later. All patients with positive scans underwent surgical exploration of the area of leukocyte accumulation, with documentation of purulence and culture of the graft. Patients with negative scans were treated as if scan results were indeterminate and underwent surgical exploration for usual clinical indications; if no exploration was performed, the patient was followed up closely for at least 1 year. Twelve of 12 positive scans showed purulence or culture evidence of infection with three different organisms; in 15 instances of negative scans, two operations were performed with one infection noted, whereas no patient without surgery has had a graft infection at 10 months follow-up. In addition to localizing graft infections, two scans demonstrated a nonvascular site of infection. Positive scans also helped determine the extent of infection along the graft, allowing better planning of the surgical procedure. These results indicate that indium 111-labeled leukocyte scans help document and localize prosthetic vascular graft infections.

  5. The direction of acceleration

    NASA Astrophysics Data System (ADS)

    Wilhelm, Thomas; Burde, Jan-Philipp; Lück, Stephan

    2015-11-01

    Acceleration is a physical quantity that is difficult to understand and hence its complexity is often erroneously simplified. Many students think of acceleration as equivalent to velocity, a ˜ v. For others, acceleration is a scalar quantity, which describes the change in speed Δ|v| or Δ|v|/Δt (as opposed to the change in velocity). The main difficulty with the concept of acceleration therefore lies in developing a correct understanding of its direction. The free iOS app AccelVisu supports students in acquiring a correct conception of acceleration by showing acceleration arrows directly at moving objects.

  6. TURBULENT SHEAR ACCELERATION

    SciTech Connect

    Ohira, Yutaka

    2013-04-10

    We consider particle acceleration by large-scale incompressible turbulence with a length scale larger than the particle mean free path. We derive an ensemble-averaged transport equation of energetic charged particles from an extended transport equation that contains the shear acceleration. The ensemble-averaged transport equation describes particle acceleration by incompressible turbulence (turbulent shear acceleration). We find that for Kolmogorov turbulence, the turbulent shear acceleration becomes important on small scales. Moreover, using Monte Carlo simulations, we confirm that the ensemble-averaged transport equation describes the turbulent shear acceleration.

  7. Position, velocity and acceleration estimates from the noisy radar measurements

    NASA Astrophysics Data System (ADS)

    Ramachandra, K. V.

    1984-04-01

    A two-dimensional Kalman tracking filter is described for obtaining optimum estimates of position, velocity and acceleration of an aircraft whose acceleration is perturbed due to maneuvers and/or other random factors. In a track-while-scan operation, a two-dimensional radar sensor is assumed to measure the range and bearing of the vehicle at uniform sampling intervals of time T seconds through random noise. The steady-state gain characteristics of the filter have been analytically obtained and the computer results are presented.

  8. Dynamic Regulation of Activated Leukocyte Cell Adhesion Molecule–mediated Homotypic Cell Adhesion through the Actin CytoskeletonV⃞

    PubMed Central

    Nelissen, Judith M. D. T.; Peters, Inge M.; de Grooth, Bart G.; van Kooyk, Yvette; Figdor, Carl G.

    2000-01-01

    Restricted expression of activated leukocyte cell adhesion molecule (ALCAM) by hematopoietic cells suggests an important role in the immune system and hematopoiesis. To get insight into the mechanisms that control ALCAM-mediated adhesion we have investigated homotypic ALCAM–ALCAM interactions. Here, we demonstrate that the cytoskeleton regulates ALCAM-mediated cell adhesion because inhibition of actin polymerization by cytochalasin D (CytD) strongly induces homotypic ALCAM–ALCAM interactions. This induction of cell adhesion is likely due to clustering of ALCAM at the cell surface, which is observed after CytD treatment. Single-particle tracking demonstrated that the lateral mobility of ALCAM in the cell membrane is increased 30-fold after CytD treatment. In contrast, both surface distribution and adhesion of a glycosylphosphatidylinositol (GPI)-anchored ALCAM mutant are insensitive to CytD, despite the increase in lateral mobility of GPI-ALCAM upon CytD treatment. This demonstrates that clustering of ALCAM is essential for cell adhesion, whereas enhanced diffusion of ALCAM alone is not sufficient for cluster formation. In addition, upon ligand binding, both free diffusion and the freely dragged distance of wild-type ALCAM, but not of GPI-ALCAM, are reduced over time, suggesting strengthening of the cytoskeleton linkage. From these findings we conclude that activation of ALCAM-mediated adhesion is dynamically regulated through actin cytoskeleton-dependent clustering. PMID:10848629

  9. Role of CD11/CD18 in shear rate-dependent leukocyte-endothelial cell interactions in cat mesenteric venules.

    PubMed Central

    Perry, M A; Granger, D N

    1991-01-01

    In vivo microscopy was used to assess the relationships among shear rate (and shear stress), leukocyte rolling velocity, and leukocyte adherence in a cat mesentery preparation. Shear rate in individual venules and arterioles of 25-35 microns diameter were varied over a wide range by graded occlusion of an arterial loop. There was a linear decline in leukocyte rolling velocity (Vwbc) as red cell velocity (Vrbc) was reduced. The ratio Vwbc/Vrbc remained constant despite variations in shear stress from 5-25 dyn/cm2. A reduction in shear stress was associated with an increased leukocyte adherence, particularly when Vwbc was reduced below 50 microns/s. Reduction in wall shear rate below 500 s-1 in arterioles allowed 1-3 leukocytes to adhere per 100 microns length of vessel, while venules exposed to the same shear rates had 5-16 adherent leukocytes. In arterioles, leukocyte rolling was only observed at low shear rates. At shear rates less than 250 s-1 leukocyte rolling velocity was faster in arterioles than venules, and the ratio Vwbc/Vrbc for arterioles was 0.08 +/- 0.02, which was fourfold higher than the ratio obtained in venules at similar shear rates. Pretreatment with the CD18-specific antibody (mAb) IB4 increased leukocyte rolling velocity in venules by approximately 20 microns/s at red cell velocities below 2,000 microns/s. mAb IB4 largely prevented the leukocyte adherence to arterioles and venules, and increased the ratio Vwbc/Vrbc observed in venules at low shear elicit a CD18-dependent adhesive interaction between leukocytes and microvascular endothelium, and that differences in shear rates cannot explain the greater propensity for leukocyte rolling and adhesion in venules than arterioles. PMID:1673690

  10. Natural sunlight accelerated weathering of photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Zerlaut, G. A.; Anderson, T. B.; Arnett, J. C.

    1981-01-01

    Photovoltaic modules are exposed to the equivalent of ten years of sunlight aging in an accelerated exposure testing and evaluation program, the objective being to determine the long-term durability characteristics of flat plate modules in comparatively short periods of time. The modules are illuminated with concentrated sunlight in a large, sun-tracking, Fresnel-reflecting solar concentrator. The effects of the accelerated exposure are assessed by performing periodic visual inspections and electrical measurements. It is found that field-experienced failure modes are duplicated, that acceleration factors of 6x to 8x are readily attainable, and that the test method is feasible as a predictive tool for photovoltaic module lifetime durability.

  11. Natural sunlight accelerated weathering of photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Zerlaut, G. A.; Anderson, T. B.; Arnett, J. C.

    Photovoltaic modules are exposed to the equivalent of ten years of sunlight aging in an accelerated exposure testing and evaluation program, the objective being to determine the long-term durability characteristics of flat plate modules in comparatively short periods of time. The modules are illuminated with concentrated sunlight in a large, sun-tracking, Fresnel-reflecting solar concentrator. The effects of the accelerated exposure are assessed by performing periodic visual inspections and electrical measurements. It is found that field-experienced failure modes are duplicated, that acceleration factors of 6x to 8x are readily attainable, and that the test method is feasible as a predictive tool for photovoltaic module lifetime durability.

  12. Soda and Cell Aging: Associations Between Sugar-Sweetened Beverage Consumption and Leukocyte Telomere Length in Healthy Adults From the National Health and Nutrition Examination Surveys

    PubMed Central

    Laraia, Barbara A.; Needham, Belinda L.; Rehkopf, David H.; Adler, Nancy E.; Lin, Jue; Blackburn, Elizabeth H.

    2014-01-01

    Objectives. We tested whether leukocyte telomere length maintenance, which underlies healthy cellular aging, provides a link between sugar-sweetened beverage (SSB) consumption and the risk of cardiometabolic disease. Methods. We examined cross-sectional associations between the consumption of SSBs, diet soda, and fruit juice and telomere length in a nationally representative sample of healthy adults. The study population included 5309 US adults, aged 20 to 65 years, with no history of diabetes or cardiovascular disease, from the 1999 to 2002 National Health and Nutrition Examination Surveys. Leukocyte telomere length was assayed from DNA specimens. Diet was assessed using 24-hour dietary recalls. Associations were examined using multivariate linear regression for the outcome of log-transformed telomere length. Results. After adjustment for sociodemographic and health-related characteristics, sugar-sweetened soda consumption was associated with shorter telomeres (b = –0.010; 95% confidence interval [CI] = −0.020, −0.001; P = .04). Consumption of 100% fruit juice was marginally associated with longer telomeres (b = 0.016; 95% CI = −0.000, 0.033; P = .05). No significant associations were observed between consumption of diet sodas or noncarbonated SSBs and telomere length. Conclusions. Regular consumption of sugar-sweetened sodas might influence metabolic disease development through accelerated cell aging. PMID:25322305

  13. Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ERα and ERβ2 and are functionally modulated by estrogens

    USGS Publications Warehouse

    Iwanowicz, Luke R.; Stafford, James L.; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W.; Blazer, Vicki

    2014-01-01

    Estrogens are recognized as modulators of immune responses in mammals and teleosts. While it is known that the effects of estrogens are mediated via leukocyte-specific estrogen receptors (ERs) in humans and mice, leucocyte-specific estrogen receptor expression and the effects of estrogens on this cell population is less explored and poorly understood in teleosts. Here in, we verify that channel catfish (Ictalurus punctaus) leukocytes express ERα and ERβ2. Transcripts of these isoforms were detected in tissue-associated leukocyte populations by PCR, but ERβ2 was rarely detected in PBLs. Expression of these receptors was temporally regulated in PBLs following polyclonal activation by concanavalin A, lipopolysaccharide or alloantigen based on evaluation by quantitative and end-point PCR. Examination of long-term leukocyte cell lines demonstrated that these receptors are differentially expressed depending on leukocyte lineage and phenotype. Expression of ERs was also temporally dynamic in some leukocyte lineages and may reflect stage of cell maturity. Estrogens affect the responsiveness of channel catfish peripheral blood leukocytes (PBLs) to mitogens in vitro. Similarly, bactericidal activity and phorbol 12-myristate 13-acetate induced respiratory burst was modulated by 17β-estradiol. These actions were blocked by the pure ER antagonist ICI 182780 indicating that response is, in part, mediated via ERα. In summary, estrogen receptors are expressed in channel catfish leukocytes and participate in the regulation of the immune response. This is the first time leukocyte lineage expression has been reported in teleost cell lines.

  14. OCULUS Sea Track Fusion Service

    NASA Astrophysics Data System (ADS)

    Panagiotou, Stylianos C.; Rizogiannis, Constantinos; Katsoulis, Stavros; Lampropoulos, Vassilis; Kanellopoulos, Sotirios; Thomopoulos, Stelios C. A.

    2015-06-01

    Oculus Sea is a complete solution regarding maritime surveillance and communications at Local as well as Central Command and Control level. It includes a robust and independent track fusion service whose main functions include: 1) Interaction with the User to suggest the fusion of two or more tracks, confirm Track ID and Vessel Metadata creation for the fused track, and suggest de-association of two tracks 2) Fusion of same vessel tracks arriving simultaneously from multiple radar sensors featuring track Association, track Fusion of associated tracks to produce a more accurate track, and Multiple tracking filters and fusion algorithms 3) Unique Track ID Generator for each fused track 4) Track Dissemination Service. Oculus Sea Track Fusion Service adopts a system architecture where each sensor is associated with a Kalman estimator/tracker that obtains an estimate of the state vector and its respective error covariance matrix. Finally, at the fusion center, association and track state estimation fusion are carried out. The expected benefits of this system include multi-sensor information fusion, enhanced spatial resolution, and improved target detection.

  15. Position 156 influences the peptide repertoire and tapasin dependency of human leukocyte antigen B*44 allotypes

    PubMed Central

    Badrinath, Soumya; Saunders, Philippa; Huyton, Trevor; Aufderbeck, Susanne; Hiller, Oliver; Blasczyk, Rainer; Bade-Doeding, Christina

    2012-01-01

    Background Polymorphic differences between donor and recipient human leukocyte antigen class I molecules can result in graft-versus-host disease due to distinct peptide presentation. As part of the peptide-loading complex, tapasin plays an important role in selecting peptides from the pool of potential ligands. Class I polymorphisms can significantly alter the tapasin-mediated interaction with the peptide-loading complex and although most class I allotypes are highly dependent upon tapasin, some are able to load peptides independently of tapasin. Several human leukocyte antigen B*44 allotypes differ exclusively at position 156 (B*44:02156Asp, 44:03156Leu, 44:28156Arg, 44:35156Glu). From these alleles, only the high tapasin-dependency of human leukocyte antigen B*44:02 has been reported. Design and Methods We investigated the influence of position 156 polymorphisms on both the requirement of tapasin for efficient surface expression of each allotype and their peptide features. Genes encoding human leukocyte antigen B*44 variants bearing all possible substitutions at position 156 were lentivirally transduced into human leukocyte antigen class I-negative LCL 721.221 cells and the tapasin-deficient cell line LCL 721.220. Results Exclusively human leukocyte antigen B*44:28156Arg was expressed on the surface of tapasin-deficient cells, suggesting that the remaining B*44/156 variants are highly tapasin-dependent. Our computational analysis suggests that the tapasin-independence of human leukocyte antigen B*44:28156Arg is a result of stabilization of the peptide binding region and generation of a more peptide receptive state. Sequencing of peptides eluted from human leukocyte antigen B*44 molecules by liquid chromatography-electrospray ionization-mass spectrometry (LTQ-Orbitrap) demonstrated that both B*44:02 and B*44:28 share the same overall peptide motif and a certain percentage of their individual peptide repertoires in the presence and/or absence of tapasin

  16. Accelerating Particles with Plasma

    SciTech Connect

    Litos, Michael; Hogan, Mark

    2014-11-05

    Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.

  17. Improved plasma accelerator

    NASA Technical Reports Server (NTRS)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  18. A New Inertial Aid Method for High Dynamic Compass Signal Tracking Based on a Nonlinear Tracking Differentiator

    PubMed Central

    Guo, Yao; Wu, Wenqi; Tang, Kanghua

    2012-01-01

    In Compass/INS integrated navigation systems, feedback inertial navigation solutions to baseband tracking loops may eliminate receiver dynamic effects, and effectively improve the tracking accuracy and sensitivity. In the conventional inertially-aided tracking loop, the satellite-receiver line-of-sight velocity is used directly to adjust local carrier frequency. However, if the inertial solution drifts, the phase tracking error will be enlarged. By using Kalman filter based carrier phase tracking loop, this paper introduces a new inertial aid method, in which the line-of-sight jerk obtained from inertial acceleration by a nonlinear tracking differentiator is used to adjust relevant parameters of the Kalman filter's process noise matrix. Validation is achieved through high dynamic Compass B3 signal with line-of-sight jerk of 10 g/s collected by a GNSS simulator. Experimental results indicate that the new inertial aid method proposed in this paper is free of the impact of the receiver dynamic and inertial errors. Therefore, when the integrated navigation system is starting or re-tracking after losing lock, the inertial error is absent from the navigation solution correction that induces large drift, and the new aid method proposed in this paper can track highly dynamic signals. PMID:22969365

  19. Analysis of cell locomotion. Contact guidance of human polymorphonuclear leukocytes.

    PubMed

    Matthes, T; Gruler, H

    1988-01-01

    The methods of statistical physics have been applied to the analysis of cell movement. Human polymorphonuclear leukocytes were exposed to different surfaces possessing parallel oriented physical structures (scratched glass surface, machine drilled aluminum surface, optical grid and stretched polyethylene foil) and cell migration was observed using time-lapse photography. We demonstrate that in cell migration along physical structures, referred to as contact guidance, two subgroups can be distinguished: 1) The nematic type where the cell size is large in relation to the grid distance of the undulate surface. 2) The smectic type where the cell size is small in relation to the grid distance of the substrate. Nematic contact guidance is characterized by an anisotropic random walk. In all substrates investigated the diffusion process parallel to the lines was faster than the diffusion process perpendicular to them. The angular dependent diffusion coefficient was described by an ellipse. Deviation from a circle defined an apolar order parameter, whose value was about 0.3. The amount of information which the cells collected from, the undulate surface was very low, between 0.1 and 0.2 bits. We demonstrate that cells do not recognize all the details of their surroundings and that their migration can be compared to the "groping around" of a short sighted man. The blurred environment can be described by a mean field whose strength is proportional to the apolar order parameter. It is argued that the anisotropic surface tension is the basic source for nematic contact guidance. Smectic contact guidance is characterized by an anisotropic random walk and is quantified by a density order parameter which is 0.28 in the case of the scratched glass surface of a Neubauer counting chamber. The information which the cells collect from their environment is very low (0.03 bits). The lines seen by the cell can be described by a mean field whose strength is proportional to the density oder

  20. Modulation of human eosinophil polymorphonuclear leukocyte migration and function.

    PubMed Central

    Goetzl, E. J.

    1976-01-01

    Eosinophil migration toward a concentration gradient of a chemotactic factor is regulated at four levels. Diverse immunologic pathways generate stimuli with eosinophil chemotactic activity, including the complement products C5a and a fragment of C3a and the peptide products of mast cells and basophils activated by IgE-mediated reactions, such as eosinophil chemotactic factor of anaphylaxis (ECF-A) and other oligopeptides. The intrinsic preferential leukocyte activity of the chemotactic stimuli represents the second level of modulation, with ECF-A and other mast cell-derived peptides exhibiting the most selective action on eosinophils. The third level of control of eosinophil chemotaxis is composed of inactivators and inhibitors of chemotactic stimuli and is exemplified by degradation of C5a by anaphylatoxin inactivator or chemotactic factor inactivator and of ECF-A by carboxypeptidase-A or aminopeptidases. The activity of ECF-A is uniquely suppressed by equimolar quantities of its NH2- terminal tripeptide substituent, presumably by eosinophil membrane receptor competition. Factors comprising the fourth level of regulation, which alter eosinophil responsiveness to chemotactic stimuli, include the chemotactic factors themselves, through deactivation; nonchemotactic inhibitors such as the COOH-terminal tripeptide substituent of ECF-A, the neutrophil-immobilizing factor (NIF), the phagocytosis-enhancing factor Thr-Lys-Pro-Arg, and histamine at concentrations greater than 400 ng/ml; and nonchemotactic enhancing principles represented by ascorbate and by histamine at concentrations of 30 ng/ml or less. Local concentrations of eosinophils called to and immobilized at the site of a hypersenitivity reaction may express their regulatory functions by degrading the chemical mediators elaborated including histamine, slow-reacting substance of anaphylaxis (SRS-A), and platelet-activating factor (PAF) by way of their content of histaminase, arylsulfatase B, and phospholipase D

  1. Interaction of Escherichia coli with Different Fimbriae and Polymorphonuclear Leukocytes

    PubMed Central

    Björkstén, Bengt; Wadström, Torkel

    1982-01-01

    The effects of Escherichia coli strains with various fimbriae on bacteria-polymorphonuclear leukocyte (PMN) interactions were studied. Strains of E. coli were cultivated at 37°C to express and at 18°C to suppress the formation of fimbriae. The presence of fimbriae was confirmed by electron microscopic studies and hemagglutination and salt aggregation tests. Fimbriated E. coli strains were more readily PMN associated than the nonfimbriated strains in the absence of opsonins, confirming the results of previous studies. However, the PMN chemiluminescence (CL) induced by the various strains in the absence of serum opsonins depended on the type of fimbriae they expressed. Strains with type 1 fimbriae expressing mannose-sensitive hemagglutination induced 5 to 15 times more CL than the same strains grown at 18°C, i.e., not expressing this type of fimbriae. For strains showing mannose-resistant hemagglutination, the differences between fimbriated and nonfimbriated variants of the same strains grown at 37 and 18°C, respectively, were less pronounced. Analysis of enterotoxigenic strains expressing colonization factor antigen I (CFA/I) fimbriae showed that these induced only 25 to 33% of the CL induced by the same E. coli strains not expressing CFA/I, whereas enterotoxigenic strains expressing CFA/II fimbriae induced 100 to 200% of the CL induced by the nonfimbriated variants. Although less CL was induced by bacteria with CFA/I fimbriae than by nonfimbriated variants, this situation was reversed when the microorganisms were opsonized. Thus, CFA/I fimbriae, while enhancing adhesion to cells, induce less activation of PMN-killing mechanisms in a serum-free environment. These findings may be relevant for the virulence in certain body sites, since CFA/I fimbriae, while facilitating adhesiveness, may protect the bacteria from PMN killing. Our findings indicate that PMN interactions with fimbriated E. coli in the host defense may be complex. Certain fimbriae may indeed be

  2. Human Leukocyte Antigen Alleles and Cytomegalovirus Infection After Renal Transplantation

    PubMed Central

    Futohi, Farzaneh; Saber, Azadeh; Nemati, Eglim; Einollahi, Behzad; Rostami, Zohre

    2015-01-01

    Background: Several studies have been conducted on the relationship between a number of human leukocyte antigen (HLA) alleles and cytomegalovirus infection (CMV), in kidney transplant recipients, after transplantation. However, only a limited number of HLAs have been investigated, so far, and the results have been contradictory. Objectives: This study aimed to investigate the relationship between 59 HLA alleles and the CMV infection, in transplant recipients, after kidney transplantation. Patients and Methods: This retrospective cohort study was conducted on 200 patients, receiving a kidney transplant, in Baqiyatallah Hospital, in Tehran, during 2013. Throughout a one-year follow-up of kidney transplant recipients, in case of detecting the CMV antigen in patients’ blood, at any time, they were placed in the group of patients with CMV infection, whereas, if no CMV-specific antigen was developed, over a year, patients were placed in the group of patients without CMV infection, after transplantation. This study investigated the relationship between CMV infection in kidney transplant recipients and 59 HLA alleles, including 14 HLA-A, 28 HLA-B, and 17 HLA-DRB1 cases. Results: Of all participants, 104 patients (52%) were diagnosed with CMV infection. There was no significant difference between the two groups, with and without CMV infection, in terms of patient’s characteristics. The CMV infection, in patients receiving a transplanted organ from deceased donor, was significantly more prevalent than in those receiving kidney transplant from living donor (63% vs. 39%, respectively, P = 0.001). Recipients with HLA-B44 were more infected with CMV compared with patients without this allele (80% vs. 50%, respectively, P = 0.024); on the contrary, kidney recipients with HLA-DRB1-1 were less infected with CMV than patients without this allele (31% vs. 55%, respectively, P = 0.020). There was no significant relationship between CMV infection and other HLA alleles. Results of

  3. Microfluidic Investigation Reveals Distinct Roles for Actin Cytoskeleton and Myosin II Activity in Capillary Leukocyte Trafficking

    PubMed Central

    Gabriele, Sylvain; Benoliel, Anne-Marie; Bongrand, Pierre; Théodoly, Olivier

    2009-01-01

    Circulating leukocyte sequestration in pulmonary capillaries is arguably the initiating event of lung injury in acute respiratory distress syndrome. We present a microfluidic investigation of the roles of actin organization and myosin II activity during the different stages of leukocyte trafficking through narrow capillaries (entry, transit and shape relaxation) using specific drugs (latrunculin A, jasplakinolide, and blebbistatin). The deformation rate during entry reveals that cell stiffness depends strongly on F-actin organization and hardly on myosin II activity, supporting a microfilament role in leukocyte sequestration. In the transit stage, cell friction is influenced by stiffness, demonstrating that the actin network is not completely broken after a forced entry into a capillary. Conversely, membrane unfolding was independent of leukocyte stiffness. The surface area of sequestered leukocytes increased by up to 160% in the absence of myosin II activity, showing the major role of molecular motors in microvilli wrinkling and zipping. Finally, cell shape relaxation was largely independent of both actin organization and myosin II activity, whereas a deformed state was required for normal trafficking through capillary segments. PMID:19450501

  4. Cellular softening mediates leukocyte demargination and trafficking, thereby increasing clinical blood counts.

    PubMed

    Fay, Meredith E; Myers, David R; Kumar, Amit; Turbyfield, Cory T; Byler, Rebecca; Crawford, Kaci; Mannino, Robert G; Laohapant, Alvin; Tyburski, Erika A; Sakurai, Yumiko; Rosenbluth, Michael J; Switz, Neil A; Sulchek, Todd A; Graham, Michael D; Lam, Wilbur A

    2016-02-23

    Leukocytes normally marginate toward the vascular wall in large vessels and within the microvasculature. Reversal of this process, leukocyte demargination, leads to substantial increases in the clinical white blood cell and granulocyte count and is a well-documented effect of glucocorticoid and catecholamine hormones, although the underlying mechanisms remain unclear. Here we show that alterations in granulocyte mechanical properties are the driving force behind glucocorticoid- and catecholamine-induced demargination. First, we found that the proportions of granulocytes from healthy human subjects that traversed and demarginated from microfluidic models of capillary beds and veins, respectively, increased after the subjects ingested glucocorticoids. Also, we show that glucocorticoid and catecholamine exposure reorganizes cellular cortical actin, significantly reducing granulocyte stiffness, as measured with atomic force microscopy. Furthermore, using simple kinetic theory computational modeling, we found that this reduction in stiffness alone is sufficient to cause granulocyte demargination. Taken together, our findings reveal a biomechanical answer to an old hematologic question regarding how glucocorticoids and catecholamines cause leukocyte demargination. In addition, in a broader sense, we have discovered a temporally and energetically efficient mechanism in which the innate immune system can simply alter leukocyte stiffness to fine tune margination/demargination and therefore leukocyte trafficking in general. These observations have broad clinically relevant implications for the inflammatory process overall as well as hematopoietic stem cell mobilization and homing. PMID:26858400

  5. KCNE gene expression is dependent on the proliferation and mode of activation of leukocytes

    PubMed Central

    Solé, Laura; Vallejo-Gracia, Albert; Roig, Sara R.; Serrano-Albarrás, Antonio; Marruecos, Laura; Manils, Joan; Gómez, Diana; Soler, Concepció; Felipe, Antonio

    2013-01-01

    Voltage-dependent K+ (Kv) channels are tightly regulated during the immune system response. Leukocytes have a limited repertoire of Kv channels, whose physiological role is under intense investigation. A functional Kv channel is an oligomeric complex composed of pore-forming and ancillary subunits. The KCNE gene family is a novel group of modulatory Kv channel elements in leukocytes. Here, we characterized the gene expression of KCNEs (1–5) in leukocytes and investigated their regulation during leukocyte proliferation and mode of activation. Murine bone-marrow-derived macrophages, human Jurkat T-lymphocytes and human Raji B-cells were analyzed. KCNEs (1–5) are expressed in all leukocytes lineages. Most KCNE mRNAs show cell cycle-dependent regulation and are differentially regulated under specific insults. Our results further suggest a new and yet undefined physiological role for KCNE subunits in the immune system. Putative associations of these ancillary proteins with Kv channels would yield a wide variety of biophysically and pharmacologically distinct channels that fine-tune the immunological response. PMID:23327879

  6. The effect of acupuncture on leukocyte levels in peripheral blood is modified by aspirin.

    PubMed

    Rivas-Vilchis, José Federico; Barrera-Escorcia, Eduardo; Fregoso-Padilla, Martha

    2009-01-01

    It has been shown that acupuncture can modify circulating levels of subpopulations of leukocytes. There have been few investigations on the effect of acupuncture on prostaglandins metabolism. Aspirin is capable of inhibiting the metabolism of prostaglandins and to produce several pharmacological effects. The objective of this study was to determine whether prior administration of aspirin could modify the action of acupuncture on levels of circulating leukocytes. Fourteen healthy males (age: 19-23 years) were recruited from a university student population. This study was a placebo-controlled, prospective, cross-over design. Subjects were randomly assigned into A or B groups. Group A received aspirin 500 mg and group B placebo, after 1 week of a washout period, group A received placebo and group B aspirin. Subjects were given acupuncture with manual needling in GV14 (Dazhui) acupoint 2 hr after receiving medication. The needle was stimulated for 10 sec and was kept in place for 5 min. Leukocytes and their subpopulations were quantified in blood samples taken immediately before and 2 hr after acupuncture treatment. In each subject pre-acupuncture values were compared to those post-acupuncture. The results showed that acupuncture significantly increased overall leukocytes (p=0.006) and neutrophils (p<0.001). Aspirin partially inhibited these effects. The data suggest that the effect of acupuncture on leukocytes may be related to levels of prostaglandins. PMID:22128425

  7. Endothelial Src kinase regulates membrane recycling from the lateral border recycling compartment during leukocyte transendothelial migration.

    PubMed

    Dasgupta, Bidisha; Muller, William A

    2008-12-01

    When leukocytes cross endothelial cells during the inflammatory response, membrane from the recently described lateral border recycling compartment (LBRC) is selectively targeted around diapedesing leukocytes. This "targeted recycling" is critical for leukocyte transendothelial migration. Blocking homophilic PECAM interactions between leukocytes and endothelial cells blocks targeted recycling from the LBRC and blocks diapedesis. However, the cellular signaling pathways that trigger targeted recycling are not known. We show that targeted recycling from the LBRC is dependent on Src kinase. The selective Src kinase inhibitor PP2 blocked targeted recycling and blocked diapedesis by over 70%. However, Src kinase inhibition did not affect the structure or normal constitutive recycling of membrane from the LBRC in the absence of leukocytes. PECAM, a Src kinase substrate, traffics between the LBRC and the endothelial surface at the cell border. However, virtually all of the PECAM in the cell that was phosphorylated on tyrosine residues was found in the LBRC. These findings demonstrate that Src kinase activity is critical for the targeted recycling of membrane from the LBRC to the site of transendothelial migration and that the PECAM in the LBRC is qualitatively different from the PECAM on the surface of endothelial cells. PMID:18991269

  8. Inhibition of leukocyte-type 12-lipoxygenase by guava tea leaves prevents development of atherosclerosis.

    PubMed

    Takahashi, Yoshitaka; Otsuki, Akemi; Mori, Yoshiko; Kawakami, Yuki; Ito, Hideyuki

    2015-11-01

    Oxidation of low-density lipoprotein (LDL) is one of the crucial steps for atherosclerosis development, and an essential role of leukocyte-type 12-lipoxygenase expressed in macrophages in this process has been demonstrated. The biochemical mechanism of the oxidation of circulating LDL by leukocyte-type 12-lipoxygenase in macrophages has been proposed. The major ingredients in guava tea leaves which inhibited the catalytic activity of leukocyte-type 12-lipoxygenase were quercetin and ethyl gallate. Administration of extracts from guava tea leaves to apoE-deficient mice significantly attenuated atherogenic lesions in the aorta and aortic sinus. We recently showed that Qing Shan Lu Shui inhibited the catalytic activity of leukocyte-type 12-lipoxygenase. The major components inhibiting the enzyme contained in Qing Shan Lu Shui were identified to be novel monoterpene glycosides. The anti-atherogenic effect of the tea leaves might be attributed to the inhibition of leukocyte-type 12-lipoxygenase by these components. PMID:25976783

  9. Red blood cells initiate leukocyte rolling in postcapillary expansions: a lattice Boltzmann analysis.

    PubMed

    Sun, Chenghai; Migliorini, Cristiano; Munn, Lance L

    2003-07-01

    Leukocyte rolling on the vascular endothelium requires initial contact between leukocytes circulating in the blood and the vessel wall. Although specific adhesion mechanisms are involved in leukocyte-endothelium interactions, adhesion patterns in vivo suggest other rheological mechanisms also play a role. Previous studies have proposed that the abundance of leukocyte rolling in postcapillary venules is due to interactions between red blood cells (RBCs) and leukocytes as they enter postcapillary expansions, but the details of the fluid dynamics have not been elucidated. We have analyzed the interactions of red and white blood cells as they flow from a capillary into a postcapillary venule using a lattice Boltzmann approach. This technique provides the complete solution of the flow field and quantification of the particle-particle forces in a relevant geometry. Our results show that capillary-postcapillary venule diameter ratio, RBC configuration, and RBC shape are critical determinants of the initiation of cell rolling in postcapillary venules. The model predicts that an optimal configuration of the trailing red blood cells is required to drive the white blood cell to the wall. PMID:12829477

  10. Cellular softening mediates leukocyte demargination and trafficking, thereby increasing clinical blood counts

    PubMed Central

    Fay, Meredith E.; Myers, David R.; Kumar, Amit; Turbyfield, Cory T.; Byler, Rebecca; Crawford, Kaci; Mannino, Robert G.; Laohapant, Alvin; Tyburski, Erika A.; Sakurai, Yumiko; Rosenbluth, Michael J.; Switz, Neil A.; Sulchek, Todd A.; Lam, Wilbur A.

    2016-01-01

    Leukocytes normally marginate toward the vascular wall in large vessels and within the microvasculature. Reversal of this process, leukocyte demargination, leads to substantial increases in the clinical white blood cell and granulocyte count and is a well-documented effect of glucocorticoid and catecholamine hormones, although the underlying mechanisms remain unclear. Here we show that alterations in granulocyte mechanical properties are the driving force behind glucocorticoid- and catecholamine-induced demargination. First, we found that the proportions of granulocytes from healthy human subjects that traversed and demarginated from microfluidic models of capillary beds and veins, respectively, increased after the subjects ingested glucocorticoids. Also, we show that glucocorticoid and catecholamine exposure reorganizes cellular cortical actin, significantly reducing granulocyte stiffness, as measured with atomic force microscopy. Furthermore, using simple kinetic theory computational modeling, we found that this reduction in stiffness alone is sufficient to cause granulocyte demargination. Taken together, our findings reveal a biomechanical answer to an old hematologic question regarding how glucocorticoids and catecholamines cause leukocyte demargination. In addition, in a broader sense, we have discovered a temporally and energetically efficient mechanism in which the innate immune system can simply alter leukocyte stiffness to fine tune margination/demargination and therefore leukocyte trafficking in general. These observations have broad clinically relevant implications for the inflammatory process overall as well as hematopoietic stem cell mobilization and homing. PMID:26858400

  11. Monoclonal antibody blockade of L-selectin inhibits mononuclear leukocyte recruitment to inflammatory sites in vivo.

    PubMed Central

    Pizcueta, P.; Luscinskas, F. W.

    1994-01-01

    L-selectin interacting with inducible endothelial counterreceptors mediates in part the initial adhesive interactions, termed rolling, between circulating blood leukocytes and vascular endothelium. While blockade of L-selectin function in in vivo models of inflammation reduces both neutrophil and lymphocyte influx at early times, little is known concerning the role of L-selectin in leukocyte recruitment at later times (> 24 hours). Using an in vivo murine model of experimentally induced inflammation of the peritoneum, the role of L-selectin in recruitment of mononuclear leukocytes to chronic sites of inflammation (48 hours) was investigated. Saturating levels of function blocking anti-L-selectin monoclonal antibody (MEL-14) or control rat IgG were maintained for 48 hours using surgically implanted mini-osmotic pumps; this treatment did not alter the circulating leukocyte cell count or differential. In animals receiving MEL-14 monoclonal antibody (MAb), macrophage and lymphocyte accumulation in response to thioglycollate was reduced by 60% (P < or = 0.0002) and > 90% (P < 0.001), respectively, at 48 hours as compared with animals implanted with pumps containing saline. Similarly, MEL-14 MAb dramatically inhibited granulocyte influx by 80% (P < 0.03) at 6 hours; recruitment at 24 and 48 hours was reduced by 50%. In contrast, the effects of purified rat IgG was not significantly different from saline. Our results suggest L-selectin, interacting with its inducible endothelial counterreceptor(s), plays an important role in circulating mononuclear leukocyte extravasation at sites of inflammation. PMID:7519828

  12. Cysteinyl leukotriene overproduction in aspirin-exacerbated respiratory disease is driven by platelet-adherent leukocytes

    PubMed Central

    Laidlaw, Tanya M.; Kidder, Molly S.; Bhattacharyya, Neil; Xing, Wei; Shen, Shiliang; Milne, Ginger L.; Castells, Mariana C.; Chhay, Heng

    2012-01-01

    Cysteinyl leukotriene (cysLT) overproduction is a hallmark of aspirin-exacerbated respiratory disease (AERD), but its mechanism is poorly understood. Because adherent platelets can convert the leukocyte-derived precursor leukotriene (LT)A4 to LTC4, the parent cysLT, through the terminal enzyme LTC4 synthase, we investigated the contribution of platelet-dependent transcellular cysLT production in AERD. Nasal polyps from subjects with AERD contained many extravascular platelets that colocalized with leukocytes, and the percentages of circulating neutrophils, eosinophils, and monocytes with adherent platelets were markedly higher in the blood of subjects with AERD than in aspirin-tolerant controls. Platelet-adherent subsets of leukocytes had higher expression of several adhesion markers than did platelet nonadherent subsets. Adherent platelets contributed more than half of the total LTC4 synthase activity of peripheral blood granulocytes, and they accounted for the higher level of LTC4 generation by activated granulocytes from subjects with AERD compared with aspirin-tolerant controls. Urinary LTE4 levels, a measure of systemic cysLT production, correlated strongly with percentages of circulating platelet-adherent granulocytes. Because platelet adherence to leukocytes allows for both firm adhesion to endothelial cells and augmented transcellular conversion of leukotrienes, a disturbance in platelet-leukocyte interactions may be partly responsible for the respiratory tissue inflammation and the overproduction of cysLTs that characterize AERD. PMID:22262771

  13. Effect of Estragole on Leukocyte Behavior and Phagocytic Activity of Macrophages

    PubMed Central

    Wiirzler, Luiz Alexandre Marques; Silva-Filho, Saulo Euclides; Kummer, Raquel; Pedroso, Raissa Bocchi; Spironello, Ricardo Alexandre; Silva, Expedito Leite; Bersani-Amado, Ciomar Aparecida; Cuman, Roberto Kenji Nakamura

    2014-01-01

    Estragole, a chemical constituent of the essential oils of many aromatic plants, is used as flavoring in beverage and food industries. In vivo and in vitro experimental assays have shown that EST has sedative, anticonvulsant, antioxidant, antimicrobial, and anesthetic activity. In this work, we evaluate the effect of EST on leukocyte behavior and phagocytic activity of macrophages. In the peritonitis model, EST (500 and 750 mg/kg) decreased the infiltration of peritoneal exudate leukocytes. In vitro chemotaxis assay showed that EST (3, 10, 30, and 60 μg/mL) inhibited neutrophil migration toward fMLP. In the in vivo microcirculation assay, EST at doses of 250, 500, and 750 mg/kg significantly reduced the number of rolling and adherent leukocytes and at doses of 250 and 500 mg/kg decreased number of leukocyte migrated to perivascular tissue. The results showed that EST (3, 10, and 30 μg/mL) was able to stimulate the macrophages phagocytosis but only at concentration of 10 μg/mL promoted an increase in nitric oxide (NO) production. In conclusion, this study showed that EST had potential anti-inflammatory effects, likely by inhibiting leukocyte migration and by stimulating macrophages phagocytosis. PMID:25152763

  14. Intramammary infections in primiparous Holsteins: heritabilities and comparisons of bovine leukocyte adhesion deficiency carriers and noncarriers.

    PubMed

    Wanner, J M; Rogers, G W; Kehrli, M E; Cooper, J B

    1998-12-01

    The objective of this study was to determine the impact of bovine leukocyte adhesion deficiency on intramammary infection (IMI) in Holstein cows at first calving. Quarter milk samples were collected between 3 d prepartum and 4 d postpartum from 756 Holstein cows in first lactation. These samples were frozen and subsequently cultured using National Mastitis Council recommendations. Sixty-eight carriers of bovine leukocyte adhesion deficiency were identified (9.0% of cows) from an additional milk sampling collected in early lactation. Binary variables (infected or uninfected) for each quarter were defined as dependent variables to evaluate IMI incidence from all bacterial species and major species groups: coliforms, coagulase-negative staphylococci, and streptococci other than Streptococcus agalactiae. The model included herd-season of calving, days in milk when samples were collected, age at calving, quarter, cow (random effect), and bovine leukocyte adhesion deficiency. Sire was included as a random effect (instead of cow), and bovine leukocyte adhesion deficiency was dropped from the model to estimate heritabilities. Heritabilities for IMI incidence from the various groups of organisms ranged from 0.02 to 0.66 (0.21 from all bacterial species). No differences were observed between carriers of bovine leukocyte adhesion deficiency and homozygous normal noncarriers for IMI from coliform, coagulase-negative staphylococci, streptococci other than Streptococcus agalactiae, or all bacterial species combined. PMID:9891275

  15. Clinical mastitis in primiparous Holsteins: comparisons of bovine leukocyte adhesion deficiency carriers and noncarriers.

    PubMed

    Wanner, J M; Rogers, G W; Kehrli, M E; Cooper, J B

    1999-11-01

    The objective of this study was to determine the impact of bovine leukocyte adhesion deficiency on clinical mastitis incidence, severity, and duration in Holstein cows. Genomic DNA from milk of 847 Holstein cows in six Pennsylvania herds was used to determine bovine leukocyte adhesion deficiency genotypes (82 or 9.7% carriers). Data on clinical mastitis incidence, severity, duration, and pathogen involved were collected during first lactation for the project cows. One hundred ninety-four cows had one or more clinical mastitis episodes; milk samples from each quarter with clinical mastitis were collected at discovery of the episode and were cultured following National Mastitis Council recommendations. The overall incidence of clinical mastitis was significantly affected by sire and herd-year-season of calving. In addition, incidence of clinical mastitis tended to increase with age at first calving. Severity and duration of clinical mastitis were impacted by the pathogen involved. Incidence of clinical mastitis from all pathogens, from coagulase-negative staphylococci, and from coliform bacteria was not significantly related to bovine leukocyte adhesion deficiency status. Carriers tended to have lower rates of mastitis from streptococci other than Streptococcus agalactiae when compared with noncarriers, but this result should be interpreted with caution because of the low frequency of mastitis from the streptococci. Bovine leukocyte adhesion deficiency status was unrelated to severity or duration of clinical episodes. Bovine leukocyte adhesion deficiency carriers are probably similar to noncarriers in resistance to clinical mastitis. PMID:10575620

  16. Exposure to Sodium Fluoride Produces Signs of Apoptosis in Rat Leukocytes

    PubMed Central

    Gutiérrez-Salinas, José; Morales-González, José A.; Madrigal-Santillán, Eduardo; Esquivel-Soto, Jaime; Esquivel-Chirino, César; González-Rubio, Manuel García-Luna y; Suástegui-Domínguez, Sigrit; Valadez-Vega, Carmen

    2010-01-01

    Fluoride is naturally present in the earth’s crust and can be found in rocks, coal, and clay; thus, it can be found in small quantities in water, air, plants, and animals. Therefore, humans are exposed to fluoride through food, drinking water, and in the air they breathe. Flouride is essential to maintain bone strength and to protect against dental decay, but if it is absorbed too frequently, it can cause tooth decay, osteoporosis, and damage to kidneys, bones, nerves, and muscles. Therefore, the present work was aimed at determining the effect of intake of sodium fluoride (NaF) as an apoptosis inducer in leukocytes of rats treated for eight weeks with 1 or 50 parts per million (ppm) NaF. Expression of p53, bcl-2, and caspade-3 were used as apoptotic and general metabolism indicators of leukocyte-like indicators of the (INT) oxidation system. Male rats were exposed to NaF (1 and 500 ppm) for eight weeks, and then sacrificed weekly to obtain blood samples. Expression of p53, bcl-2, and caspase-3 were determined in leukocytes by Western blot, and general metabolism of leukocytes was analyzed with a commercial kit. We found changes in the expression of the proteins described, especially when the animals received 50 ppm of NaF. These results indicate that NaF intoxication can be an apoptosis inducer in rat leukocytes treated with the compound for eight weeks. PMID:20957113

  17. In-111-labeled leukocytes in the diagnosis of rejection and cytomegalovirus infection in renal transplant patients

    SciTech Connect

    Forstrom, L.A.; Loken, M.K.; Cook, A.; Chandler, R.; McCullough, J.

    1981-04-01

    Indium-111-labelled (In-111) leukocytes have been shown to be useful in the localization of inflammatory processes, including renal transplant rejection. Using previously reported labelling methods, 63 studies with this agent have been performed in 53 renal transplant patients. Indications for study included suspected rejection or cytomegalovirus (CMV) infection. Studies were performed in 33 men and 20 women, with ages ranging from 6 to 68 years. Autologous cells were normally used for labeling, although leukocytes obtained from ABO-compatible donors were used in three subjects. Rectilinear scanner and/or scintillation camera images were obtained at 24 hours after intravenous administration of 0.1 to 0.6 mCi of In-111 leukocytes. There was abnormal uptake of In-111-leukocytes in the transplanted kidney in 11 of 15 cases of rejection. In three additional cases of increased transplant uptake, CMV infection was present in two. Abnormal lung uptake was present in 13 of 14 patients with CMV infection. In four additional cases, increased lung uptake was associated with other pulmonary inflammatory disease. Increased lung activity was not seen in patients with uncomplicated transplant rejection. These results suggest that In-111-leukocyte imaging may be useful in the differential diagnosis of rejection versus CMV infection in renal transplant patients.

  18. In-111-labeled leukocytes in the diagnosis of rejection and cytomegalovirus infection in renal transplant patients

    SciTech Connect

    Forstrom, L.A.; Loken, M.K.; Cook, A.; Chandler, R.; McCullough, J.

    1981-04-01

    Indium-111-labeled (In-111) leukocytes have been shown to be useful in the localization of inflammatory processes, including renal transplant rejection. Using previously reported labeling methods, 63 studies with this agent have been performed in 53 renal transplant patients. Indications for study included suspected rejection or cytomegalovirus (CMV) infection. Studies were performed in 33 men and 20 women, with ages ranging from 6 to 68 years. Autologous cells were normally used for labeling, although leukocytes obtained from ABO-compatible donors were used in three subjects. Rectilinear scanner and/or scintillation camera images were obtained at 24 hours after intravenous administration of 0.1 to 0.6 mCi of In-111-leukocytes. There was abnormal uptake of In-111-leukocytes in the transplanted kidney in 11 of 15 cases of rejection. In three additional cases of increased transplant uptake, CMV infection was present in two. Abnormal lung uptake was present in 13 of 14 patients with CMV infection. In four additional cases, increased lung uptake was associated with other pulmonary inflammatory disease. Increased lung activity was not seen in patients with uncomplicated transplant rejection. These results suggest that In-111-leukocyte imaging may be useful in the differential diagnosis of rejection versus CMV infection in renal transplant patients.

  19. Red Blood Cells Initiate Leukocyte Rolling in Postcapillary Expansions: A Lattice Boltzmann Analysis

    PubMed Central

    Sun, Chenghai; Migliorini, Cristiano; Munn, Lance L.

    2003-01-01

    Leukocyte rolling on the vascular endothelium requires initial contact between leukocytes circulating in the blood and the vessel wall. Although specific adhesion mechanisms are involved in leukocyte-endothelium interactions, adhesion patterns in vivo suggest other rheological mechanisms also play a role. Previous studies have proposed that the abundance of leukocyte rolling in postcapillary venules is due to interactions between red blood cells (RBCs) and leukocytes as they enter postcapillary expansions, but the details of the fluid dynamics have not been elucidated. We have analyzed the interactions of red and white blood cells as they flow from a capillary into a postcapillary venule using a lattice Boltzmann approach. This technique provides the complete solution of the flow field and quantification of the particle-particle forces in a relevant geometry. Our results show that capillary-postcapillary venule diameter ratio, RBC configuration, and RBC shape are critical determinants of the initiation of cell rolling in postcapillary venules. The model predicts that an optimal configuration of the trailing red blood cells is required to drive the white blood cell to the wall. PMID:12829477

  20. Selection of the best features for leukocytes classification in blood smear microscopic images

    NASA Astrophysics Data System (ADS)

    Sarrafzadeh, Omid; Rabbani, Hossein; Talebi, Ardeshir; Banaem, Hossein Usefi

    2014-03-01

    Automatic differential counting of leukocytes provides invaluable information to pathologist for diagnosis and treatment of many diseases. The main objective of this paper is to detect leukocytes from a blood smear microscopic image and classify them into their types: Neutrophil, Eosinophil, Basophil, Lymphocyte and Monocyte using features that pathologists consider to differentiate leukocytes. Features contain color, geometric and texture features. Colors of nucleus and cytoplasm vary among the leukocytes. Lymphocytes have single, large, round or oval and Monocytes have singular convoluted shape nucleus. Nucleus of Eosinophils is divided into 2 segments and nucleus of Neutrophils into 2 to 5 segments. Lymphocytes often have no granules, Monocytes have tiny granules, Neutrophils have fine granules and Eosinophils have large granules in cytoplasm. Six color features is extracted from both nucleus and cytoplasm, 6 geometric features only from nucleus and 6 statistical features and 7 moment invariants features only from cytoplasm of leukocytes. These features are fed to support vector machine (SVM) classifiers with one to one architecture. The results obtained by applying the proposed method on blood smear microscopic image of 10 patients including 149 white blood cells (WBCs) indicate that correct rate for all classifiers are above 93% which is in a higher level in comparison with previous literatures.

  1. The role of myeloid differentiation factor 88 on mitochondrial dysfunction of peritoneal leukocytes during polymicrobial sepsis

    PubMed Central

    Zou, Lin; Chen, Dunjin; Chao, Wei

    2016-01-01

    Objective To investigate the role of myeloid differentiation factor 88 (MyD88) on mitochondrial dysfunction of peritoneal leukocytes during polymicrobial sepsis. Material and methods Polymicrobial peritonitis, a clinically relevant mouse model of sepsis, was generated by cecum ligation and puncture (CLP) in both male C57BL/6J wild-type (WT) and MyD88 knockout (MyD88–/–) mice. Twenty-four hours after surgeries, peritoneal leukocytes were collected and four parameters of mitochondrial function, including total intracellular and mitochondrial ROS burst, mitochondrial membrane depolarization and ATP depletion, were measured by flow cytometry or ATP assay, and then compared. Results Polymicrobial sepsis led to a marked mitochondrial dysfunction of peritoneal leukocytes with total intracellular and mitochondrial ROS overproduction, decreased mitochondrial membrane potential and reduced intracellular ATP production. In comparison, there was no significant difference in the extent of mitochondrial dysfunction of peritoneal leukocytes between WT and MyD88–/– septic mice. Conclusions MyD88 may be not sufficient to regulate mitochondrial dysfunction of peritoneal leukocytes during polymicrobial sepsis. PMID:27536200

  2. Microfluidic chambers for monitoring leukocyte trafficking and humanized nano-proresolving medicines interactions

    PubMed Central

    Jones, Caroline N.; Dalli, Jesmond; Dimisko, Laurie; Wong, Elisabeth; Serhan, Charles N.; Irimia, Daniel

    2012-01-01

    Leukocyte trafficking plays a critical role in determining the progress and resolution of inflammation. Although significant progress has been made in understanding the role of leukocyte activation in inflammation, dissecting the interactions between different leukocyte subpopulations during trafficking is hampered by the complexity of in vivo conditions and the lack of detail of current in vitro assays. To measure the effects of the interactions between neutrophils and monocytes migrating in response to various chemoattractants, at single-cell resolution, we developed a microfluidic platform that replicates critical features of focal inflammation sites. We integrated an elastase assay into the focal chemotactic chambers (FCCs) of our device that enabled us to distinguish between phlogistic and nonphlogistic cell recruitment. We found that lipoxin A4 and resolvin D1, in solution or incorporated into nano–proresolving medicines, reduced neutrophil and monocyte trafficking toward leukotriene B4. Lipoxin A4 also reduced the elastase release from homogenous and heterogenous mixtures of neutrophils and monocytes. Surprisingly, the effect of resolvin D1 on heterogenous mixtures was antisynergistic, resulting in a transient spike in elastase activity, which was quickly terminated, and the degraded elastin removed by the leukocytes inside the FCCs. Therefore, the microfluidic assay provides a robust platform for measuring the effect of leukocyte interactions during trafficking and for characterizing the effects of inflammation mediators. PMID:23185003

  3. Telomere length assessment in leukocytes presents potential diagnostic value in patients with breast cancer

    PubMed Central

    BARCZAK, WOJCIECH; ROZWADOWSKA, NATALIA; ROMANIUK, ALEKSANDRA; LIPIŃSKA, NATALIA; LISIAK, NATALIA; GRODECKA-GAZDECKA, SYLWIA; KSIĄŻEK, KRZYSZTOF; RUBIŚ, BŁAŻEJ

    2016-01-01

    Telomere shortening is associated with cancer development, primarily through the induction of genomic instability. The majority of studies have indicated that individuals with shorter blood telomeres may be at a higher risk of developing various types of cancer. There is increasing evidence that the study of the alterations in telomere length may improve cancer prognosis. The aim of the present study was to verify the use of telomere length parameters in the diagnostics of breast cancer stage. Telomere length was analyzed in the blood leukocytes of 52 patients with breast cancer relative to 47 control subjects using quantitative polymerase chain reaction. The effects of stage, grade, estrogen receptor, progesterone receptor and human epidermal growth factor 2 (HER2) status were assessed. The current study demonstrated that the average telomeric sequence length was significantly shorter in leukocytes from individuals diagnosed with a more severe stage of breast cancer (T2N1M0) than in leukocytes in the early stages of the disease (T1N0M0) (P=0.0207). Furthermore, the data indicated that telomeres in leukocytes derived from patients with HER2+ breast cancer were significantly longer compared with those with the HER2− type (P=0.0347). These results suggest that the assessment of telomeres in blood leukocytes may, at least partially, correspond with breast cancer staging and HER2 receptor status. PMID:26998167

  4. Leukocyte ABCA1 controls susceptibility to atherosclerosis and macrophage recruitment into tissues

    PubMed Central

    Van Eck, Miranda; Bos, I. Sophie T.; Kaminski, Wolfgang E.; Orsó, Evelyn; Rothe, Gregor; Twisk, Jaap; Böttcher, Alfred; Van Amersfoort, Edwin S.; Christiansen-Weber, Trudy A.; Fung-Leung, Wai-Ping; Van Berkel, Theo J. C.; Schmitz, Gerd

    2002-01-01

    The ATP-binding cassette transporter 1 (ABCA1) has recently been identified as a key regulator of high-density lipoprotein (HDL) metabolism, which is defective in familial HDL-deficiency syndromes such as Tangier disease. ABCA1 functions as a facilitator of cellular cholesterol and phospholipid efflux, and its expression is induced during cholesterol uptake in macrophages. To assess the role of macrophage ABCA1 in atherosclerosis, we generated low-density lipoprotein (LDL) receptor knockout (LDLr−/−) mice that are selectively deficient in leukocyte ABCA1 (ABCA1−/−) by using bone marrow transfer (ABCA1−/− → LDLr−/−). Here we demonstrate that ABCA1−/− → LDLr−/− chimeras develop significantly larger and more advanced atherosclerotic lesions compared with chimeric LDLr−/− mice with functional ABCA1 in hematopoietic cells. Targeted disruption of leukocyte ABCA1 function did not affect plasma HDL cholesterol levels. The amount of macrophages in liver and spleen and peripheral blood leukocyte counts is increased in the ABCA1−/− → LDLr−/− chimeras. Our results provide evidence that leukocyte ABCA1 plays a critical role in the protection against atherosclerosis, and we identify ABCA1 as a leukocyte factor that controls the recruitment of inflammatory cells. PMID:11972062

  5. Reactive oxygen species mediate angiotensin II-induced leukocyte-endothelial cell interactions in vivo.

    PubMed

    Alvarez, A; Sanz, M J

    2001-08-01

    Chronically elevated angiotensin II (Ang-II)-induced hypertension is partly mediated by superoxide production. In this study, we have investigated whether the leukocyte-endothelial cell interactions elicited by Ang-II involve reactive oxygen species (ROS) generation. Intravital microscopy within the rat mesenteric microvessels was used. Superfusion (60 min) with Ang-II (1 nM) induced significant increases in leukocyte rolling flux, adhesion, and emigration, which were inhibited by pretreatment with superoxide dismutase or catalase. Dihydrorhodamine-123 oxidation indicated that ROS are primarily produced by the vessel wall. Administration of dimethylthiourea, desferrioxamine, or N-acetylcysteine provoked significant reductions in Ang-II-induced leukocyte-endothelial cell interactions. In addition, a blockade of platelet-activating factor or leukotrienes also attenuated such responses significantly. The results presented indicate that in vivo Ang-II-induced leukocyte recruitment is dependent on the generation of intra- and extracellular ROS. Therefore, the use of anti-oxidants might constitute an alternative therapy for the control of the subendothelial leukocyte infiltration associated with hypertension and atherosclerosis. PMID:11493611

  6. Mechanisms of endothelial cell-dependent leukocyte adhesion stimulated by platelet-activating factor.

    PubMed

    Ding, Z; Li, S; Wu, Z

    1992-04-01

    Platelet-activating factor (PAF) stimulates leukocyte-endothelial cell (EC) adhesion through its effects either on leukocytes or on ECs. ECs may be injured, synthesize, or express new adhesive proteins to increase leukocyte adhesion. Intermediary mediators produced by activated ECs are also likely involved in promoting leukocyte adhesion. Our experiments demonstrated that PAF induced no obvious damage to bovine pulmonary artery ECs evaluated by lactic dehydrogenase release rate, angiotensin-converting enzyme activity, and cellular malondialdehyde content. Treatment of EC monolayers with 10(-9) M PAF increased polymorphonuclear leukocyte (PMN) adhesion. Increasing PAF concentration did not induce more PMN adherence. PAF elicited both a rapid and prolonged increment of PMN adherence to EC monolayers. The rapid adherence was greatly attenuated by pretreatment of ECs with PAF receptor antagonist SRI 63-441 but was not affected by pretreatment of PMNs with SRI 63-441, suggesting that PAF increases PMN adherence rapidly through its effects on specific receptors on ECs. Increased PMN adherence lasted if PAF treatment of ECs was sustained for 3 or 6 h. Pretreatment of ECs with actinomycin D, a protein synthesis inhibitor, significantly decreased PAF-induced sustained PMN adherence, but the inhibition is incomplete, suggesting that other mechanisms than protein synthesis also participated in the prolonged PMN adherence. We concluded from the results that PAF may induce both rapid and prolonged PMN adhesion to ECs. The effects are receptor mediated. The prolonged PMN adhesion is partly the result of protein synthesis. PMID:1592489

  7. Reduced platelet-mediated and enhanced leukocyte-mediated fibrinolysis in experimentally induced diabetes in rats

    SciTech Connect

    Winocour, P.D.; Colwell, J.A.

    1985-05-01

    Studies of fibrinolytic activity in diabetes mellitus have produced conflicting results. This may be a result of methodologic insensitivity or of variable contributions of the different blood components to whole blood fibrinolysis. To explore these two possibilities, the authors used a sensitive solid-phase radiometric assay to examine the fibrinolytic activity of whole blood, platelet-rich plasma, leukocytes, and platelet- and leukocyte-poor plasma prepared from control rats and rats with streptozocin-induced diabetes at various times after induction of diabetes. Fibrinolytic activity of whole blood from diabetic rats after 7 days was significantly reduced, and remained reduced after longer durations of diabetes up to 28 days. Platelet-rich plasma from diabetic rats had decreased fibrinolytic activity, which followed the same time course of changes as in whole blood. The platelet contribution to whole blood fibrinolysis was further reduced in vivo after 14 days of diabetes by a reduced whole blood platelet count. In contrast, fibrinolytic activity of leukocytes from diabetic rats became enhanced after 7 days of diabetes. After 49 days of diabetes, the whole blood leukocyte count was reduced, and in vivo would offset the enhanced activity. Plasma fibrinolytic activity was small compared with that of whole blood and was unaltered in diabetic rats. The authors conclude that altered platelet function contributes to decreased fibrinolytic activity of whole blood in diabetic rats, and that this may be partially offset by enhanced leukocyte-mediated fibrinolysis.

  8. Hydrodynamic forces on a wall-bound leukocyte due to interactions with flowing red cells

    NASA Astrophysics Data System (ADS)

    Isfahani, Amir H. G.; Freund, Jonathan B.

    2011-11-01

    As part of both healthy and pathologically physiological mechanisms sphere-like white blood cells (leukocytes) adhere to the walls of small blood vessels. We use quantitative numerical simulations to compare the forces from flowing red blood cells on a wall-adhered leukocyte to a homogenized model of blood at the same flow conditions. We model the highly flexible red blood cells using a fast O (N log N) boundary integral formulation. These elastic membranes deform substantially but strongly resist surface dilatation. They enclose a higher than plasma viscosity hemoglobin solution. The no-slip condition is enforced on the stationary leukocyte as well as the vessel walls. Vessel diameters of 10 to 20 microns are studied. Different hematocrits, leukocyte shapes, and flow conditions are examined. In vessels comparable to the size of the cells, we show that the particulate character of blood significantly affects the magnitude of the forces that the leukocyte experiences, transiently increasing it well above the homogenized-blood prediction: for example, for a tube hematocrit of 25 % and a spherical protrusion with a diameter 0.75 that of the tube, the average forces are increased by about 40 % and the local forces by more than 100 % relative to those expected for a blood model homogenized by its effective viscosity.

  9. 1995 Fast Track: cost reduction and improvement.

    PubMed

    Panzer, R J; Tuttle, D N; Kolker, R M

    1997-01-01

    To respond to a cost reduction crisis, Strong Memorial Hospital implemented an aggressively managed program of accelerated improvement teams. "Fast-track" teams combined the application of many management tools (total quality management, breakthrough thinking, reengineering, etc.) into one problem-solving process. Teams and managers were charged to work on specific cost reduction strategies. Teams were given additional instruction on interpersonal skills such as communication, teamwork, and leadership. Paradoxically, quality improvement in our hospital was advanced more through this effort at cost reduction than had previously been done in the name of quality itself. PMID:10176411

  10. Fast Track'' nuclear thermal propulsion concept

    SciTech Connect

    Johnson, R.A.; Zweig, H.R. ); Cooper, M.H.; Wett, J. Jr. )

    1993-01-10

    The objective of the Space Exploration Initiative ( America at the Threshold...,'' 1991) is the exploration of Mars by man in the second decade of the 21st century. The NASA Fast Track'' approach (NASA-LeRC Presentation, 1992) could accelerate the manned exploration of Mars to 2007. NERVA-derived nuclear propulsion represents a viable near-term technology approach to accomplish the accelerated schedule. Key milestones in the progression to the manned Mars mission are (1) demonstration of TRL-6 for the man-rateable system by 1999, (2) a robotic lunar mission by 2000, (3) the first cargo mission to Mars by 2005, and (4) the piloted Mars mission in 2007. The Rocketdyne-Westinghouse concept for nuclear thermal propulsion to achieve these milestones combines the nuclear reactor technology of the Rover/NERVA programs and the state-of-the-art hardware designs from hydrogen-fueled rocket engine successes like the Space Shuttle Main Engine (SSME).

  11. Acceleration gradient of a plasma wakefield accelerator

    SciTech Connect

    Uhm, Han S.

    2008-02-25

    The phase velocity of the wakefield waves is identical to the electron beam velocity. A theoretical analysis indicates that the acceleration gradient of the wakefield accelerator normalized by the wave breaking amplitude is K{sub 0}({xi})/K{sub 1}({xi}), where K{sub 0}({xi}) and K{sub 1}({xi}) are the modified Bessel functions of the second kind of order zero and one, respectively and {xi} is the beam parameter representing the beam intensity. It is also shown that the beam density must be considerably higher than the diffuse plasma density for the large radial velocity of plasma electrons that are required for a high acceleration gradient.

  12. Far field acceleration

    SciTech Connect

    Fernow, R.C.

    1995-07-01

    Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail.

  13. Angular Acceleration Without Torque?

    NASA Astrophysics Data System (ADS)

    Kaufman, Richard D.

    2012-01-01

    Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.2

  14. Sustained linear acceleration

    NASA Technical Reports Server (NTRS)

    Fraser, T. M.

    1973-01-01

    The subjective effects of sustained acceleration are discussed, including positive, negative, forward, backward, and lateral acceleration effects. Physiological effects, such as retinal and visual response, unconsciousness and cerebral function, pulmonary response, and renal output, are studied. Human tolerance and performance under sustained acceleration are ascertained.

  15. Angular Acceleration without Torque?

    ERIC Educational Resources Information Center

    Kaufman, Richard D.

    2012-01-01

    Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

  16. Acceleration: It's Elementary

    ERIC Educational Resources Information Center

    Willis, Mariam

    2012-01-01

    Acceleration is one tool for providing high-ability students the opportunity to learn something new every day. Some people talk about acceleration as taking a student out of step. In actuality, what one is doing is putting a student in step with the right curriculum. Whole-grade acceleration, also called grade-skipping, usually happens between…

  17. Magnetic Low-Friction Track

    NASA Astrophysics Data System (ADS)

    Paetkau, Mark; Bahniwal, Manpreet; Gamblen, James

    2008-05-01

    The standard low-friction tracks used to test Newton's laws are the air track and the low-friction cart track. Both are commercially available and provide low-friction environments to test various physics concepts. At a recent science fair, one of the authors (JG) presented a magnetically levitated cart and track. A literature search found no previous testing of magnetically levitated carts. This paper compares a magnetically levitated cart against the two standard low-friction tracks.

  18. High Phobic Anxiety Is Related to Lower Leukocyte Telomere Length in Women

    PubMed Central

    Okereke, Olivia I.; Prescott, Jennifer; Wong, Jason Y. Y.; Han, Jiali; Rexrode, Kathryn M.; De Vivo, Immaculata

    2012-01-01

    Background Chronic psychological distress has been linked to shorter telomeres, an indication of accelerated aging. Yet, little is known about relations of anxiety to telomeres. We examined whether a typically chronic form of anxiety – phobic anxiety – is related to telomere length. Methodology/Principal Findings Relative telomere lengths (RTLs) in peripheral blood leukocytes were measured by quantitative real-time polymerase chain reaction among 5,243 women (aged 42–69 years) who: were participants in the Nurses' Health Study; were controls in prior case-control studies of telomeres and disease, or randomly selected healthy participants in a cognitive function sub-study; had completed the Crown-Crisp phobic index proximal to blood collection. Adjusted least-squares mean RTLs (z-scores) were calculated across phobic categories. Higher phobic anxiety was generally associated with lower RTLs (age-adjusted p-trend = 0.09); this association was similar after adjustment for confounders – paternal age-at-birth, smoking, body mass index (BMI) and physical activity (p-trend = 0.15). Notably, a threshold was identified. Among women with Crown-Crisp<6 points, the multivariable-adjusted least-squares mean RTL z-score = 0.02 standard units; however, among the most phobic women (Crown-Crisp≥6), the multivariable-adjusted least-squares mean RTL z-score = −0.09 standard units (mean difference = −0.10 standard units; p = 0.02). The magnitude of this difference was comparable to that for women 6 years apart in age. Finally, effect modification by BMI, smoking and paternal age was observed: associations were stronger among highly phobic women with BMI≥25 kg/m2, without smoking history, or born to fathers aged ≥40 years. Conclusions/Significance In this large, cross-sectional study high phobic anxiety was associated with shorter telomeres. These results point toward prospective investigations relating anxiety to telomere length change. PMID

  19. Track recording plastic compositions

    NASA Technical Reports Server (NTRS)

    Tarle, Gregory (Inventor)

    1983-01-01

    Improved nuclear track recording plastic compositions are provided which exhibit greatly decreased surface roughness when etched to produce visible tracks of energetic nuclear particles which have passed into and/or through said plastic. The improved compositions incorporate a small quantity of a phthalic acid ester into the major plastic component which is derived from the polymerization of monomeric di-ethylene glycol bis allyl carbonate. Di-substituted phthalic acid esters are preferred as the added component, with the further perference that the ester substituent has a chain length of 2 or more carbon atoms. The inclusion of the phthalic acid ester to an extent of from about 1-2% by weight of the plastic compositions is sufficient to drastically reduce the surface roughness ordinarily produced when the track recording plastic is contacted by etchants.

  20. Tracks to therapy

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.

    1999-01-01

    Studies of the structure of particle tracks have led to models of track effects based on radial dose and radiobiological target theory that have been very successful in describing and predicting track effects in physical, chemical, and biological systems. For describing mammalian cellular inactivation two inactivation modes are required, called gamma-kill and ion-kill, the first due to synergistic effects of delta rays from adjacent ion paths thus resembling the effects from gamma rays, and the second to the effects of single ion transits through a cell nucleus. The ion-kill effect is more severe, where the fraction of cells experiencing ion kill is responsible for a decrease in the oxygen enhancement ratio, and an increase in relative biological effectiveness, but these are accompanied by loss of repair, hence to a reduction in the efficiency of fractionation in high LET therapy, as shown by our calculations for radiobiological effects in the "spread out Bragg Peak".